WO2020216362A1

WO2020216362A1 - System and method for treating voc gas in engine exhaust gas

Info

Publication number: WO2020216362A1
Application number: PCT/CN2020/086857
Authority: WO
Inventors: 唐万福; 赵晓云; 王大祥; 段志军; 邹永安; 奚勇
Original assignee: 上海必修福企业管理有限公司
Priority date: 2019-04-25
Filing date: 2020-04-24
Publication date: 2020-10-29
Also published as: CN216974977U; WO2020216367A1; CN113710350A; WO2020216361A1; CN113748258A; WO2020216368A1; WO2020216364A1; WO2020216363A1; CN218235209U; CN113748259A; CN113747976A; CN113710366A; WO2020216365A1; WO2020216369A1; CN113727781A; WO2020216370A1; WO2020216366A1; CN113710881A

Abstract

Provided are a system and method for treating VOC gas in engine exhaust gas. The system comprises: an inlet, an outlet, and a flow channel located between the inlet and the outlet, and further comprises an ultraviolet ray apparatus (4) and an exhaust gas electric field apparatus (5), wherein the ultraviolet ray apparatus (4) and the exhaust gas electric field apparatus (5) are arranged along the flow channel in the direction from the inlet to the outlet in sequence, the exhaust gas electric field apparatus (5) comprises: an electric field apparatus inlet (51), an electric field apparatus outlet (52), an electric field cathode (10212) and an electric field anode (10211), and the electric field cathode (10212) and the electric field anode (10211) are used to generate an ionizing dust-removal electric field. The electric field is used for dust removal to effectively remove nanoparticles in the product of engine exhaust gas and gas after the engine exhaust gas is treated by means of ultraviolet ray irradiation.

Description

System and method for processing VOCs in engine tail gas

Technical field

The invention belongs to the field of environmental protection, and relates to a system and method for processing VOCs in engine tail gas.

Background technique

The engine's pollution to the environment mainly comes from engine exhaust, which is engine exhaust. Engine exhaust contains a large amount of volatile organic compounds (VOCs), carbon monoxide (CO), nitrogen oxides (NO _x ), etc. Cause serious pollution. In particular, the VOCs contained in engine exhaust mainly include hydrocarbons (alkanes, aromatic hydrocarbons, olefins), and hydrocarbon derivatives (halogenated hydrocarbons, aldehydes, ketones, alcohols, structures containing N/S atoms) and so on. VOCs are substances that can directly harm the human body and affect the health of the human body. They not only have a stimulating effect on human vision, smell, and respiratory systems, but also damage the heart, lungs and other organs and the nervous system. In addition, VOCs can react with other pollutants in the atmospheric environment, causing local or global environmental problems. For example, under the action of sunlight (ultraviolet light), VOCs can react photochemically with NOx to form fine suspended particles and photochemical smog. Harm to health and reduce crop production.

In view of the fact that there are many sources of VOCs, emissions are increasing year by year, and the composition of VOCs is extremely complex, the development of effective methods to reduce VOCs emissions has always been a hot and difficult point in industry research. To reduce the emission of VOCs in the atmosphere, it can be controlled from the source of the emission, or the end of the emission can be comprehensively treated.

For high-concentration VOCs (greater than 5000mg/m ³ ), it is suitable for recovery and recycling. There are adsorption method, absorption method, membrane separation method, etc. The physical adsorption method only converts VOCs from gaseous form to adsorbed state. The organic matter of VOCs needs further treatment, and the adsorbent has to undergo repeated regeneration processes.

For low and medium concentrations of VOCs, molecular degradation technology is often used to control, mainly including catalytic combustion method, photocatalysis method, low temperature plasma method, photolysis method, photocatalytic oxidation method, etc. Among them, catalytic combustion technology is limited by high-priced metal catalysts, excessive energy consumption, catalyst poisoning and deactivation, and the flammable and explosive characteristics of VOCs at high temperatures. The photocatalytic oxidation technology is a method that can achieve the decomposition of low-concentration VOCs at room temperature. It is considered a promising treatment process, but it is also limited by the deactivation of the catalyst and the regeneration of holes by electrons. The photocatalytic oxidation technology can achieve high VOCs removal efficiency at the beginning of the reaction, but during the reaction process, photocatalytic oxidation intermediate deposits will be formed on the surface of the photocatalyst, resulting in a decrease in the catalytic activity of the photocatalyst.

Ultraviolet (UV) degradation of VOCs technology is a simple method to eliminate VOCs. At the same time, UV degradation technology does not use catalysts, has lower cost and operability, and has attracted the attention of the industry. UV photodegradation of VOCs has two reaction pathways: one reaction pathway is photolysis reaction, which can also be called photodissociation. The typical technology is UV lamp, because the energy of short-wavelength ultraviolet photons is higher than that of chemical bonds in most pollutant molecules. Bond energy, the 185nm wavelength ultraviolet light emitted by the UV lamp has a higher energy (6.7eV), which can be used to destroy and decompose the chemical bond structure of various VOCs, including benzene, toluene, xylene and other difficult organic Molecular structure; another reaction pathway is the photooxidation reaction. The high-energy photons produced by ultraviolet light with a wavelength of 185nm can activate O ₂ and H ₂ O water vapor molecules to produce a large number of active free radicals with strong oxidizing properties, such as O(1D ), O(3P), hydroxyl radicals (*OH), O _3, etc., can continue to oxidize and decompose VOCs molecules and their newly generated intermediate small molecules, thereby reducing the concentration of pollutants.

In the actual engineering case, it is found that in the process of using UV photolysis technology to treat VOCs, photodegradation and photopolymerization reaction occur simultaneously. Photodegradation can generate harmless CO ₂ and H ₂ O, and the product of photopolymerization reaction is polymer Polymers, which appear as dust particles (large molecular weight organic solid particles), directly discharged will cause secondary pollution to the environment. However, in the existing process route of using photolysis technology to treat VOCs, only the change in the concentration of VOCs is detected, and the particulate product of the polymerization reaction is not considered. As a product of photolysis technology, particulate matter is a product of photolysis technology. If it is not intercepted and collected, let it be discharged. Into the atmosphere, causing excessive dust hazards to the environment.

Electrostatic dust removal is a gas dust removal method, usually used in metallurgy, chemistry and other industrial fields to purify gas or recover useful dust particles. In the prior art, due to the large space occupation, complex system structure, poor dust removal effect (especially, only large particles can be removed, and the dust removal efficiency is significantly reduced under the condition of high temperature or low temperature tail gas containing water droplets), etc., it cannot be based on Electrostatic dust removal processes engine exhaust particles.

Summary of the invention

In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a system and method for processing VOCs in engine exhaust, which is used to solve at least one of the problems of the prior art engine exhaust treatment system requiring regular maintenance and unstable effects. Solve the problem that the prior art cannot effectively remove the VOCs component in the engine exhaust. The inventor of the present application has discovered new problems in the technology of ultraviolet treatment of exhaust gas containing VOCs through research, and found corresponding technical means to solve these problems. For example, the prior art did not recognize it, but the inventor of the present application found that the product after UV irradiation treatment of exhaust gas containing VOCs contains nanoparticles, especially particles below 50nm, especially particles around 23nm, so it needs to be discharged to The operation of removing nanoparticles is carried out before the air. In addition, the inventors of the present application found that the electric field dust removal system they invented can effectively remove the nanoparticles in the products after UV treatment of the exhaust gas containing VOCs, especially the particles below 50nm, and avoid secondary pollution, thus solving the problem for those skilled in the art. Did not recognize the technical problems, and achieved unexpected technical effects. At the same time, the inventors of the present application have discovered new problems in the existing ionization dust removal technology through research, and solved them through a series of technical means. For example, when the exhaust gas temperature or the engine temperature is lower than a certain temperature, the engine exhaust may contain Liquid water, the present invention installs a water removal device in front of the tail gas electric field device to remove liquid water in the tail gas, and improve the effect of photolysis VOCs and ionization dust removal; under high temperature conditions, by controlling the dust collecting area of the tail gas electric field device anode and the cathode The discharge area ratio, the length of the cathode/anode, the distance between the electrodes and the auxiliary electric field, etc., effectively reduce the electric field coupling, and make the exhaust electric field device still have a high-efficiency dust collection capacity under high temperature impact. Therefore, the present invention is suitable for operation under severe conditions and ensures the removal efficiency of VOCs and the removal efficiency of nanoparticles in the exhaust gas. Therefore, from a commercial point of view, the present invention is fully applicable to engines.

In order to achieve the above objectives and other related objectives, the present invention provides the following examples:

1. Example 1 provided by the present invention: a system for processing VOCs in engine exhaust, including:

Inlet, outlet, and flow path between inlet and outlet;

It also includes an ultraviolet device and a tail gas electric field device, and the ultraviolet device and the tail gas electric field device are sequentially arranged along the flow channel from the inlet to the outlet.

2. Example 2 provided by the present invention: including the above example 1, wherein the ultraviolet device includes at least one ultraviolet lamp.

3. Example 3 provided by the present invention: including the above example 1 or 2, wherein the ultraviolet light provided by the ultraviolet lamp is single-peak ultraviolet light or double-peak ultraviolet light.

4. Example 4 provided by the present invention: includes any one of the foregoing Examples 1-3, wherein the main peak of the single-peak ultraviolet light provided by the ultraviolet lamp is 253.7 nm or 185 nm.

5. Example 5 provided by the present invention: includes any one of the above examples 1-4, wherein the main peaks of the double-peak ultraviolet light provided by the ultraviolet lamp are 253.7 nm and 185 nm, respectively.

6. Example 6 provided by the present invention: including the above example 1, wherein the exhaust electric field device includes an electric field device inlet, an electric field device outlet, an electric field cathode and an electric field anode, and the electric field cathode and the electric field anode are used to generate exhaust gas ionization Dust removal electric field.

7. Example 7 provided by the present invention: including the above example 6, wherein the electric field anode includes a first anode part and a second anode part, the first anode part is close to the entrance of the electric field device, and the second anode part is close to the outlet of the electric field device At least one cathode support plate is arranged between the first anode part and the second anode part.

8. Example 8 provided by the present invention: It includes any one of the above examples 1-7, wherein the exhaust electric field device further includes an exhaust gas insulation mechanism for realizing the connection between the cathode support plate and the electric field anode insulation.

9. Example 9 provided by the present invention: including the above example 8, wherein an electric field flow channel is formed between the electric field anode and the electric field cathode, and the exhaust gas insulation mechanism is arranged outside the electric field flow channel.

10. Example 10 provided by the present invention: including the above examples 8 or 9, wherein the exhaust gas insulation mechanism includes an insulating part and a heat insulating part; the material of the insulating part is a ceramic material or a glass material.

11. Example 11 provided by the present invention: including the above example 10, wherein the insulating portion is an umbrella-shaped string ceramic column, an umbrella-shaped string glass column, a columnar string ceramic column or a columnar glass column, with glaze on the inside and outside of the umbrella or the inside and outside of the column.

12. Example 12 provided by the present invention: including the above example 11, wherein the distance between the outer edge of the umbrella string ceramic column or the umbrella string glass column and the electric field anode is more than 1.4 times the electric field distance, and the umbrella string ceramic column Or the sum of the pitch of the umbrella ledge of the umbrella-shaped glass column is 1.4 times or more of the insulation pitch of the umbrella-shaped ceramic column or umbrella-shaped glass column. The total length of the umbrella edge of the umbrella-shaped ceramic column or umbrella-shaped glass column is the umbrella. The insulation distance of the shaped string ceramic column or umbrella string glass column is more than 1.4 times.

13. Example 13 provided by the present invention: including any one of the above examples 7 to 12, wherein the length of the first anode portion is 1/10 to 1/4, 1/4 to the length of the electric field anode 1/3, 1/3 to 1/2, 1/2 to 2/3, 2/3 to 3/4, or 3/4 to 9/10.

14. Example 14 provided by the present invention: includes any one of the above examples 7 to 13, wherein the length of the first anode part is long enough to remove some dust and reduce accumulation in the exhaust gas insulation mechanism and The dust on the cathode support plate reduces electric breakdown caused by dust.

15. Example 15 provided by the present invention: includes any one of the above examples 7 to 14, wherein the second anode part includes a dust accumulation section and a reserved dust accumulation section.

16. Example 16: provided by the present invention: includes any one of the above examples 6 to 15, wherein the electric field cathode includes at least one electrode rod.

17. Example 17 provided by the present invention: including the above example 16, wherein the diameter of the electrode rod is not greater than 3 mm.

18. Example 18 provided by the present invention: including the above examples 16 or 17, wherein the shape of the electrode rod is needle-like, polygonal, burr-like, threaded rod-like or column-like.

19. Example 19 provided by the present invention: including any one of the above examples 6 to 18, wherein the electric field anode is composed of a hollow tube bundle.

20. Example 20 provided by the present invention: includes the above example 19, wherein the hollow cross section of the electric field anode tube bundle is circular or polygonal.

21. Example 21 provided by the present invention: includes the above example 20, wherein the polygon is a hexagon.

22. Example 22 provided by the present invention: includes any one of the above examples 19 to 21, wherein the tube bundle of the electric field anode is in a honeycomb shape.

23. Example 23 provided by the present invention: includes any one of the above examples 6 to 22, wherein the electric field cathode penetrates the electric field anode.

24. Example 24 provided by the present invention: includes any one of the foregoing Examples 6 to 23, wherein the length of the electric field anode is 10-90 mm, and the length of the electric field cathode is 10-90 mm.

25. Example 25 provided by the present invention: including the above example 24, wherein when the electric field temperature is 200°C, the corresponding dust collection efficiency is 99.9%.

26. Example 26 provided by the present invention: including the above examples 24 or 25, wherein when the electric field temperature is 400° C., the corresponding dust collection efficiency is 90%.

27. Example 27 provided by the present invention: includes any one of the foregoing Examples 24 to 26, wherein when the electric field temperature is 500° C., the corresponding dust collection efficiency is 50%.

28. Example 28 provided by the present invention: includes any one of the foregoing Examples 1 to 27, wherein the exhaust electric field device further includes an auxiliary electric field unit for generating an auxiliary electric field that is not parallel to the exhaust ionization and dust removal electric field.

29. Example 29 provided by the present invention: includes any one of the foregoing Examples 1 to 27, wherein the exhaust electric field device further includes an auxiliary electric field unit, the exhaust ionization dust removal electric field includes a flow channel, and the auxiliary electric field unit uses To generate an auxiliary electric field that is not perpendicular to the flow channel.

30. The example 30 provided by the present invention includes the above example 28 or 29, wherein the auxiliary electric field unit includes a first electrode, and the first electrode of the auxiliary electric field unit is arranged at or near the entrance of the exhaust gas ionization and dust removal electric field.

31. Example 31 provided by the present invention: includes the above example 30, wherein the first electrode is a cathode.

32. Example 32 provided by the present invention: includes the above example 30 or 31, wherein the first electrode of the auxiliary electric field unit is an extension of the electric field cathode.

33. Example 33 provided by the present invention: including the above example 32, wherein the first electrode of the auxiliary electric field unit and the electric field anode have an angle α, and 0°<α≤125°, or 45°≤α≤ 125°, or 60°≤α≤100°, or α=90°.

34. Example 34 provided by the present invention: includes any one of the foregoing Examples 28 to 33, wherein the auxiliary electric field unit includes a second electrode, and the second electrode of the auxiliary electric field unit is arranged at or near the exhaust gas ionization The outlet of the dedusting electric field.

35. Example 35 provided by the present invention: including the above example 34, wherein the second electrode is an anode.

36. Example 36 provided by the present invention: includes the above example 34 or 35, wherein the second electrode of the auxiliary electric field unit is an extension of the electric field anode.

37. Example 37 provided by the present invention: including the above example 36, wherein the second electrode of the auxiliary electric field unit and the electric field cathode have an included angle α, and 0°<α≤125°, or 45°≤α≤ 125°, or 60°≤α≤100°, or α=90°.

38. Example 38 provided by the present invention: includes any one of the foregoing Examples 28 to 31, 34, and 35, wherein the electrode of the auxiliary electric field and the electrode of the exhaust gas ionization dust removal electric field are arranged independently.

39. Example 39 provided by the present invention: includes any one of the foregoing Examples 6 to 38, wherein the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is 1.667:1 to 1680:1.

40. Example 40 provided by the present invention: includes any one of the foregoing Examples 6 to 38, wherein the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is 6.67:1 to 56.67:1.

41. Example 41 provided by the present invention: includes any one of the above examples 6 to 40, wherein the diameter of the electric field cathode is 1-3 mm, and the distance between the electric field anode and the electric field cathode is 2.5-139.9 Mm; the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is 1.667:1 to 1680:1

42. Example 42 provided by the present invention: includes any one of the foregoing Examples 6 to 40, wherein the distance between the electric field anode and the electric field cathode is less than 150 mm.

43. Example 43 provided by the present invention: includes any one of the foregoing Examples 6 to 40, wherein the distance between the electric field anode and the electric field cathode is 2.5-139.9 mm.

44. Example 44 provided by the present invention: includes any one of the foregoing Examples 6 to 40, wherein the distance between the electric field anode and the electric field cathode is 5-100 mm.

45. Example 45 provided by the present invention: includes any one of the foregoing Examples 6 to 44, wherein the length of the electric field anode is 10-180 mm.

46. Example 46 provided by the present invention: includes any one of the foregoing Examples 6 to 44, wherein the length of the electric field anode is 60-180 mm.

47. Example 47 provided by the present invention: includes any one of the foregoing Examples 6 to 46, wherein the length of the electric field cathode is 30-180 mm.

48. Example 48 provided by the present invention: includes any one of the foregoing Examples 6 to 46, wherein the electric field cathode length is 54-176 mm.

49. Example 49 provided by the present invention: includes any one of the foregoing Examples 39 to 48, wherein, when operating, the number of coupling times of the exhaust gas ionization and dust removal electric field is ≤3.

50. Example 50 provided by the present invention: includes any one of the foregoing Examples 28 to 48, wherein, when operating, the number of coupling times of the exhaust gas ionization and dust removal electric field is ≤3.

51. Example 51 provided by the present invention: includes any one of the foregoing Examples 6 to 50, wherein the electric field voltage of the tail gas ionization and dust removal has a value range of 1kv-50kv.

52. Example 52 provided by the present invention: includes any one of the above examples 6 to 51, wherein the exhaust electric field device further includes a number of connecting shells, and the series electric field stages are connected through the connecting shells.

53. Example 53 provided by the present invention: includes the above example 52, wherein the distance between adjacent electric field levels is greater than 1.4 times the pole pitch.

54. Example 54 provided by the present invention: includes any one of the above-mentioned Examples 1 to 53, which further includes a water removal device for removing liquid water before the entrance of the electric field device.

55. Example 55 provided by the present invention: includes the above-mentioned example 54, wherein, when the exhaust gas temperature or the engine temperature is lower than a certain temperature, the water removal device removes liquid water in the exhaust gas.

56. Example 56 provided by the present invention: including the above example 55, wherein the certain temperature is above 90°C and below 100°C.

57. Example 57 provided by the present invention: including the above example 55, wherein the certain temperature is above 80°C and below 90°C.

58. Example 58 provided by the present invention: includes the above example 55, wherein the certain temperature is below 80°C.

59. Example 59 provided by the present invention: includes any one of the foregoing Examples 1 to 58, wherein the exhaust gas cooling device is further included for reducing the exhaust gas temperature before the entrance of the electric field device.

60. Example 60 provided by the present invention: includes the above example 59, wherein the exhaust gas cooling device includes a heat exchange unit for performing heat exchange with the exhaust gas of the engine to heat the liquid heat exchange medium in the heat exchange unit into a gaseous state The heat exchange medium.

61. Example 61 provided by the present invention: includes the above example 60, wherein the heat exchange unit includes:

The exhaust gas passage cavity is connected with the exhaust pipe of the engine, and the exhaust gas passage cavity is used for the exhaust gas of the engine to pass through;

The medium gasification chamber is used for converting the liquid heat exchange medium into a gas after heat exchange with the tail gas.

62. Example 62 provided by the present invention: includes any one of the above examples 60 to 61, wherein the exhaust gas cooling device further includes a heat preservation pipe connected to the exhaust pipe of the engine and the heat exchange unit between.

63. Example 63 provided by the present invention: includes any one of the above examples 59 to 62, wherein the exhaust gas cooling device includes a fan that cools the exhaust gas before passing air into the entrance of the electric field device The role of.

64. Example 64 provided by the present invention: including the above example 63, wherein the air introduced is 50% to 300% of the exhaust gas.

65. Example 65 provided by the present invention: including the above example 63, wherein the air introduced is 100% to 180% of the exhaust gas.

66. Example 66 provided by the present invention: including the above example 63, wherein the air introduced is 120% to 150% of the exhaust gas.

67. Example 67 provided by the present invention: includes any one of the foregoing Examples 1 to 66, wherein the engine further includes an engine.

68. Example 68 provided by the present invention: includes any one of the above examples 1 to 67, wherein the VOCs processing system in the engine exhaust further includes an adsorption device, and the adsorption device is arranged between the ultraviolet device and the electric field Between devices.

69. Example 69 provided by the present invention: includes the above example 68, wherein the adsorption device is provided with an adsorption material.

70. Example 70 provided by the present invention: includes the above example 69, wherein the adsorption material includes at least one of activated carbon and molecular sieve.

71. Example 71 provided by the present invention: A method for processing VOCs in engine exhaust, including the following steps:

The engine exhaust is subjected to UV treatment to obtain the product after UV treatment;

The product after UV treatment of engine exhaust is subjected to electric field dust removal treatment to remove particulate matter in the product after UV treatment.

72. Example 72 provided by the present invention: including Example 71, wherein the method for treating VOCs in engine exhaust gas further includes subjecting the product after UV treatment to adsorption treatment before the electric field dust removal treatment.

73. Example 73 provided by the present invention: including Example 72, wherein the adsorbent for the adsorption treatment is activated carbon and/or molecular sieve.

74. Example 74 provided by the present invention: includes any one of Examples 71-73, wherein at least one ultraviolet lamp is used during UV treatment.

75. Example 75 provided by the present invention: includes any one of the foregoing Examples 71-74, wherein the ultraviolet light provided by the ultraviolet lamp is single-peak ultraviolet light or double-peak ultraviolet light.

76. Example 76 provided by the present invention: includes any one of the foregoing Examples 71-75, wherein the main peak of the single-peak ultraviolet light provided by the ultraviolet lamp is 253.7 nm or 185 nm.

77. Example 77 provided by the present invention: includes the above examples 71-76, wherein the main peaks of the dual-peak ultraviolet light provided by the ultraviolet lamp are 253.7 nm and 185 nm, respectively.

78. Example 78 provided by the present invention: including any one of Examples 71-77, the electric field dust removal processing method further includes: a method for reducing electric field coupling of engine exhaust dust removal, including the following steps:

Choose electric field anode parameters or/and electric field cathode parameters to reduce the number of electric field couplings.

79. Example 79 provided by the present invention: includes Example 78, which includes selecting the ratio of the dust collection area of the electric field anode to the discharge area of the electric field cathode.

80. Example 80 provided by the present invention includes Example 79, wherein the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is selected to be 1.667:1 to 1680:1.

81. Example 81 provided by the present invention includes Example 79, wherein the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is selected to be 6.67:1 to 56.67:1.

82. Example 82 provided by the present invention: including any one of Examples 78 to 81, including selecting the electric field cathode to have a diameter of 1-3 mm, and the distance between the electric field anode and the electric field cathode to be 2.5-139.9 mm The ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is 1.667:1 to 1680:1.

83. Example 83 provided by the present invention: includes any one of Examples 78 to 82, wherein the distance between the electric field anode and the electric field cathode is selected to be less than 150 mm.

84. Example 84 provided by the present invention: includes any one of Examples 78 to 82, wherein the distance between the electric field anode and the electric field cathode is selected to be 2.5-139.9 mm.

85. Example 85 provided by the present invention: includes any one of Examples 78 to 82, wherein the distance between the electric field anode and the electric field cathode is selected to be 5-100 mm.

86. Example 86 provided by the present invention: includes any one of Examples 78 to 85, including selecting the electric field anode length to be 10-180 mm.

87. Example 87 provided by the present invention: includes any one of Examples 78 to 85, which includes selecting the electric field anode length to be 60-180 mm.

88. Example 88 provided by the present invention: includes any one of Examples 78 to 87, including selecting the electric field cathode length to be 30-180 mm.

89. Example 89 provided by the present invention: includes any one of Examples 78 to 87, including selecting the electric field cathode length to be 54-176 mm.

90. Example 90 provided by the present invention: includes any one of Examples 78 to 89, wherein it includes selecting that the electric field cathode includes at least one electrode rod.

91. Example 91 provided by the present invention: including Example 90, which includes selecting the electrode rod to have a diameter not greater than 3 mm.

92. Example 92 provided by the present invention: includes example 90 or 91, which includes selecting the shape of the electrode rod to be needle, polygon, burr, threaded rod, or column.

93. Example 93 provided by the present invention: includes any one of Examples 78 to 92, wherein it includes selecting that the electric field anode is composed of a hollow tube bundle.

94. Example 94 provided by the present invention: including Example 93, wherein the hollow section including the anode tube bundle is selected to be circular or polygonal.

95. Example 95 provided by the present invention: includes Example 94, which includes selecting the polygon as a hexagon.

96. Example 96 provided by the present invention: includes any one of Examples 93 to 95, wherein the tube bundle including the selection of the electric field anode is in a honeycomb shape.

97. Example 97 provided by the present invention: includes any one of Examples 78 to 96, wherein it includes selecting the electric field cathode to penetrate into the electric field anode.

98. Example 98 provided by the present invention: includes any one of Examples 78 to 97, wherein the size of the electric field anode or/and the electric field cathode is selected such that the number of electric field couplings is ≤3.

99. Example 99 provided by the present invention: including any one of Examples 71-98, the electric field dust removal treatment method further includes: an engine exhaust dust removal method, including the following steps: when the exhaust gas temperature is lower than 100°C, the exhaust gas is removed The liquid water is then ionized to remove dust.

100. Example 100 provided by the present invention: including Example 99, where the exhaust gas is ionized to remove dust when the exhaust gas temperature is ≥100°C.

101. Example 101 provided by the present invention: including Example 99 or 100, wherein when the exhaust gas temperature is ≤90°C, the liquid water in the exhaust gas is removed, and then the dust is removed by ionization.

102. Example 102 provided by the present invention: includes Example 99 or 100, wherein when the exhaust gas temperature is ≤80°C, the liquid water in the exhaust gas is removed, and then the dust is removed by ionization.

103. Example 103 provided by the present invention: includes Example 99 or 100, wherein when the exhaust gas temperature is ≤70°C, the liquid water in the exhaust gas is removed, and then the dust is removed by ionization.

104. Example 104 provided by the present invention: including Example 99 or 100, wherein the liquid water in the tail gas is removed by an electrocoagulation defogging method, and then ionization is used to remove dust.

105. Example 105 provided by the present invention: includes any one of Examples 71 to 104, wherein the product after UV treatment of exhaust gas contains nanoparticles, and the removal of particulate matter in the product after UV treatment of exhaust gas includes removing the UV treatment exhaust gas Nanoparticles in the final product.

106. Example 106 provided by the present invention: includes any one of Examples 71 to 105, wherein the product after UV treatment of exhaust gas contains particulate matter less than 50nm, and the removal of particulate matter in the product after UV treatment of the exhaust gas includes removing UV After processing the exhaust gas, the particulate matter smaller than 50nm in the product.

107. Example 107 provided by the present invention: includes any one of Examples 71 to 106, wherein the product after UV treatment of exhaust gas contains 15-35 nanometers of particulate matter, and the product after removal of UV treatment exhaust gas includes particulate matter Remove 15-35 nanometer particles in the product after UV treatment.

108. Example 108 provided by the present invention: includes any one of Examples 71 to 107, wherein the product after UV treatment of exhaust gas contains 23nm particulate matter, and the removal of particulate matter in the product after UV treatment of the exhaust gas includes removal of UV treatment 23nm particles in the product after the exhaust.

109. Example 109 provided by the present invention: includes any one of Examples 71 to 108, wherein the removal rate of 23nm particulate matter in the product after removing the UV-treated tail gas is ≥93%.

110. Example 110 provided by the present invention: includes any one of Examples 71 to 109, wherein the removal rate of 23nm particulate matter in the product after removing the UV-treated tail gas is ≥95%.

111. Example 111 provided by the present invention: includes any one of Examples 71 to 110, wherein the removal rate of 23nm particulate matter in the product after removing the UV-treated tail gas is ≥99.99%.

In the present invention, the product after UV treatment of exhaust gas contains nanoparticles in the "nanoparticulate matter" refers to particulate matter with a particle size of less than 1 μm.

Description of the drawings

FIG. 1 is a schematic diagram of a three-dimensional structure of an exhaust gas treatment device in an engine exhaust dust removal system according to an embodiment of the present invention.

Fig. 2 is a schematic diagram showing the structure of an umbrella-shaped exhaust gas insulation mechanism in an exhaust gas treatment device of the engine exhaust dust removal system of the present invention.

Fig. 3 shows a schematic diagram of an engine exhaust dust removal system according to Embodiment 2 of the present invention.

4 is a schematic diagram of the structure of the electric field generating unit in Embodiments 3-8, 10-13, and 15-18 of the present invention.

Fig. 5 is an A-A view of the electric field generating unit of Fig. 4 in embodiment 3, embodiment 6 and embodiment 13 of the present invention.

Fig. 6 is an A-A view of the electric field generating unit of Fig. 4 with length and angle marked in embodiment 3 and embodiment 6 of the present invention.

FIG. 7 is a schematic diagram of the electric field device structure of two electric field levels in Embodiment 3, Embodiment 6 and Embodiment 13 of the present invention.

FIG. 8 is a schematic structural diagram of an electric field device in Embodiment 19 of the present invention.

FIG. 9 is a schematic structural diagram of an electric field device in Embodiment 21 of the present invention.

FIG. 10 is a schematic structural diagram of an electric field device in Embodiment 22 of the present invention.

Fig. 11 is a schematic structural diagram of an exhaust gas cooling device in embodiment 24 of the present invention.

Fig. 12 is a schematic diagram of the flow chart of the test device of Example 25 of the present invention.

Fig. 13 is a curve of the VOCs concentration and the VOCs removal rate at the outlet of the electric field device of Example 25 of the present invention over time.

Fig. 14 is a curve of the CO ₂ concentration at the outlet of the electric field device of Example 25 of the present invention as a function of processing time.

Fig. 15 is a curve of PM2.5 at the outlet of the electric field device of Example 25 of the present invention with processing time.

FIG. 16 is a schematic diagram of the flow chart of the test device of Example 31 of the present invention.

Fig. 17 is a curve of VOCs concentration changes with time at the air inlet, air outlet, and air outlet of the adsorption device when purifying low VOCs concentration in Example 31 of the present invention.

Fig. 18 is a graph showing the change of CO ₂ concentration at the inlet, outlet, and outlet of the adsorption device of the ultraviolet device with time when purifying low VOCs concentration in Example 31 of the present invention.

Fig. 19 is a curve of VOCs concentration change with time at the air inlet, air outlet, and air outlet of the adsorption device when purifying high VOCs concentration in Example 31 of the present invention.

Fig. 20 is a graph showing the change of CO ₂ concentration at the inlet, outlet, and outlet of the adsorption device of the ultraviolet device with time when purifying high VOCs concentration in Example 31 of the present invention.

Detailed ways

The following specific examples illustrate the implementation of the present invention. Those familiar with the technology can easily understand the other advantages and effects of the present invention from the content disclosed in this specification.

It should be noted that the structures, proportions, sizes, etc. shown in the accompanying drawings in this specification are only used to match the content disclosed in the specification for people familiar with this technology to understand and read, and are not intended to limit the implementation of the present invention Limited conditions, so it has no technical significance. Any structural modification, proportional relationship change or size adjustment should still fall under the present invention without affecting the effects and objectives that can be achieved by the present invention. The disclosed technical content must be within the scope of coverage. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" cited in this specification are only for the convenience of description and are not used to limit the text. The scope of implementation of the invention, the change or adjustment of its relative relationship, without substantial changes to the technical content, shall also be regarded as the scope of implementation of the invention.

The engine exhaust dust removal system of the present invention is connected with the outlet of the engine. The exhaust gas emitted by the engine will flow through the engine exhaust dust removal system.

In some embodiments of the present invention, a gas treatment system for VOCs in engine exhaust is provided, which includes: an inlet, an outlet, and a flow channel between the inlet and the outlet; and an ultraviolet device, an exhaust electric field device, and the ultraviolet device , The tail gas electric field device is arranged along the flow channel in sequence from the inlet to the outlet. When the VOCs processing system in the engine exhaust is working, the gas enters the flow channel from the inlet, and the gas in the flow channel first enters the ultraviolet device, and the ultraviolet-treated gas enters the electric field device to remove the particulate matter in the ultraviolet-treated gas. Discharge from the outlet.

In an embodiment of the present invention, the technical effects obtained by the combination of UV treatment + electric field dust removal and purification of VOCs gas are as follows:

The research of the present invention has found that the products of the engine exhaust containing VOCs after UV irradiation treatment are not only CO ₂ and H ₂ O, but also large-molecular-weight nano-scale solid particles. For example, the present invention is verified by a large amount of experimental data: UV-treated exhaust The content of PM2.5 in the product after UV irradiation increased significantly, and the nano-sized particles in the UV treatment product increased significantly. Among them, the PN value of solid particles with a particle size of 23nm increased by more than 1 times. If the product is directly discharged after UV irradiation , Will cause secondary pollution. Therefore, the removal of particulate matter needs to be considered in the UV treatment of gas containing VOCs. However, the prior art has not found any relevant research on the removal of nano-particles in the product after UV irradiation treatment, nor has it disclosed a technique for effectively removing the nano-particles in the gas. The invention utilizes electric field dust removal to effectively remove nano particles in the product after UV irradiation treatment, and the removal efficiency of 23nm particles reaches more than 99.99%, avoiding secondary pollution.

In some embodiments of the present invention, the ultraviolet device includes at least one ultraviolet lamp.

In some embodiments of the present invention, the UV light provided by the ultraviolet lamp is single-peak ultraviolet light or double-peak ultraviolet light.

In some embodiments of the present invention, the main peak of the single peak ultraviolet light provided by the ultraviolet lamp is 253.7 nm or 185 nm.

In some embodiments of the present invention, the main peaks of the double-peak ultraviolet light provided by the ultraviolet lamp are 253.7 nm and 185 nm, respectively.

In some embodiments of the present invention, the VOCs processing system in engine exhaust further includes an adsorption device, and the adsorption device is arranged in the flow channel of the VOCs processing system in engine exhaust.

In some embodiments of the present invention, the adsorption device is located between the ultraviolet device and the electric field device.

In some embodiments of the present invention, the adsorption device includes an air inlet and an air outlet, the air inlet of the adsorption device communicates with the air outlet of the ultraviolet device, and the air outlet of the adsorption device is connected to the electric field. The electric field device inlet of the device is connected.

In some embodiments of the present invention, the adsorption device is provided with an adsorption material, the adsorption material includes but not limited to activated carbon, molecular sieve, and also includes other adsorbable VOCs, VOCs in the photolysis process, ozone oxidation process, UV light the product and any intermediate product at least one substance adsorbent material excitation oxide generated during, for example, photolysis products adsorbing material ₃ O VOCs.

In some embodiments of the present invention, the adsorption material includes at least one of hydrophilic engineered activated carbon and hydrophobic engineered molecular sieve.

In an embodiment of the present invention, the adsorption purification technology has the following functions:

First: UV light cannot completely treat VOCs in engine exhaust into CO ₂ and H ₂ O during the ultraviolet treatment stage, and will produce intermediate products, and cannot degrade all VOCs components. In the adsorption device, H ₂ O and UV light products are produced. e.g. O _3, OH ^-, and the intermediate product is not enough time to degradation and agglomeration VOCs are adsorbed component is adsorbed on the adsorbent material in the pores of the intermediate product and not enough time to UV degradation of the VOCs component O _3, OH ^- and other strong oxidants Under the action, it is further decomposed into CO ₂ and H ₂ O, desorbed from the pores of the adsorbent material, and assisted in the UV light treatment of VOCs. At the same time, it realizes online desorption to avoid adsorbent failure and ensure that the adsorbent can be reused. VOCs processing efficiency.

Second: In terms of economy, the amount of VOCs released is not constant in actual application operations. When the concentration of VOCs is high, UV light cannot completely degrade VOCs, and the remaining VOCs (VOCs that are not degraded by UV during the UV purification stage) are adsorbed It is stored in the adsorbent material, concentrated and concentrated, and is further oxidized and decomposed again under the action of strong oxidizing agents such as O ₃ , OH ^- and other products of UV light; when the concentration of VOCs is very low, the strong oxidizing ion hydroxyl radical ( *OH) Enter the adsorption device to further catalyze the VOCs stored in the adsorption material into CO ₂ and H ₂ O. This improves the efficiency of VOCs gas treatment, saves energy consumption, and can also realize the miniaturization of VOCs gas treatment equipment.

Third: The adsorption material can absorb the ozone produced by photolysis. The adsorbed ozone oxidizes the VOCs accumulated in the adsorption material, so that O _{3 can} be fully utilized, and the secondary pollution caused by ozone can be avoided.

In an embodiment of the present invention, the combination of ultraviolet purification and adsorption purification improves the efficiency of UV purification of VOCs gas, saves energy consumption, and makes the VOCs processing system in engine exhaust miniaturized.

In some embodiments of the present invention, a method for processing VOCs in engine exhaust is provided, which includes the following steps:

The product after UV treatment of exhaust gas is subjected to electric field dust removal treatment to remove particulate matter.

In an embodiment of the present invention, the method for treating VOCs in engine exhaust further includes performing electric field dust removal treatment on the gas before UV treatment.

In an embodiment of the present invention, the method for treating VOCs in engine exhaust further includes subjecting the product after UV treatment to the exhaust gas to be adsorbed, and then subjected to electric field dust removal treatment.

In an embodiment of the present invention, the adsorbent for the adsorption treatment is activated carbon and/or molecular sieve.

In an embodiment of the present invention, at least one ultraviolet lamp is used during the UV irradiation treatment.

In an embodiment of the present invention, the UV light provided by the ultraviolet lamp is single-wave peak ultraviolet light or double-wave peak ultraviolet light.

In an embodiment of the present invention, the main peak of the single peak ultraviolet light provided by the ultraviolet lamp is 253.7 nm or 185 nm.

In an embodiment of the present invention, the main peaks of the dual peak ultraviolet light provided by the ultraviolet lamp are 253.7 nm and 185 nm, respectively.

In an embodiment of the present invention, the product after UV treatment of exhaust gas contains nanoparticles, and the removal of particles in the product after UV treatment of exhaust gas includes the removal of nanoparticles in the product after UV treatment of exhaust gas.

In an embodiment of the present invention, the product after UV treatment exhaust gas contains particles smaller than 50nm, and the product after removing UV treatment exhaust gas includes particles smaller than 50nm in the product after removing UV treatment exhaust gas. .

In an embodiment of the present invention, the product after UV treatment of exhaust gas contains 15-35 nanometer particles, and the product after removal of UV treatment exhaust gas includes 15-35 nanometers in the product after removing UV treatment exhaust gas. 35-nanometer particles.

In an embodiment of the present invention, the product after UV treatment of exhaust gas contains 23nm particulate matter, and the product after removal of UV treatment exhaust gas includes 23nm particulate matter in the product after removal of UV treatment exhaust gas.

In an embodiment of the present invention, the removal rate of 23nm particles in the product after removing the UV-treated tail gas is ≥93%.

In an embodiment of the present invention, the removal rate of 23nm particulate matter in the product after removing the UV treatment tail gas is ≥95%.

In an embodiment of the present invention, the removal rate of 23nm particles in the product after removing the UV-treated tail gas is ≥99.99%.

In an embodiment of the present invention, the inlet of the electric field device is connected with the outlet of the engine.

In an embodiment of the present invention, the exhaust electric field device may include an electric field cathode and an electric field anode, and an ionization dust removal electric field is formed between the electric field cathode and the electric field anode. When the exhaust gas enters the ionization dust removal electric field, the oxygen ions in the exhaust gas will be ionized and form a large amount of charged oxygen ions. The oxygen ions combine with dust and other particles in the exhaust gas to charge the particles, and the electric field anode adsorbs the negatively charged particles Force, the particles are adsorbed on the anode of the electric field to remove the particles in the exhaust gas.

In an embodiment of the present invention, the electric field cathode includes a plurality of cathode wires. The diameter of the cathode wire can be 0.1mm-20mm, and the size parameter can be adjusted according to the application situation and dust accumulation requirements. In an embodiment of the present invention, the diameter of the cathode wire is not greater than 3 mm. In an embodiment of the present invention, the cathode wire uses a metal wire or an alloy wire that is easy to discharge, is temperature-resistant, can support its own weight, and is electrochemically stable. In an embodiment of the present invention, the material of the cathode wire is titanium. The specific shape of the cathode wire is adjusted according to the shape of the electric field anode. For example, if the dust accumulation surface of the electric field anode is flat, the cross section of the cathode wire is circular; if the dust accumulation surface of the electric field anode is an arc surface, the cathode wire needs to be designed as Polyhedral. The length of the cathode wire is adjusted according to the electric field anode.

In an embodiment of the present invention, the electric field cathode includes a plurality of cathode rods. In an embodiment of the present invention, the diameter of the cathode rod is not greater than 3 mm. In an embodiment of the present invention, the cathode rod uses a metal rod or alloy rod that is easy to discharge. The shape of the cathode rod can be needle-like, polygonal, burr-like, threaded rod-like or column-like. The shape of the cathode rod can be adjusted according to the shape of the electric field anode. For example, if the dust accumulation surface of the electric field anode is flat, the cross section of the cathode rod needs to be designed to be circular; if the dust accumulation surface of the electric field anode is an arc surface, the cathode The rod needs to be designed in a multi-faceted shape.

In an embodiment of the present invention, the electric field cathode is penetrated in the electric field anode.

In an embodiment of the present invention, the electric field anode includes one or more hollow anode tubes arranged in parallel. When there are multiple hollow anode tubes, all the hollow anode tubes constitute a honeycomb electric field anode. In an embodiment of the present invention, the cross section of the hollow anode tube may be circular or polygonal. If the cross section of the hollow anode tube is circular, a uniform electric field can be formed between the electric field anode and the electric field cathode, and the inner wall of the hollow anode tube is not easy to accumulate dust. If the hollow anode tube has a triangular cross section, 3 dust accumulation surfaces and 3 remote dust holding angles can be formed on the inner wall of the hollow anode tube. The hollow anode tube with this structure has the highest dust holding rate. If the cross section of the hollow anode tube is quadrilateral, 4 dust accumulation surfaces and 4 dust holding angles can be obtained, but the assembly structure is unstable. If the cross section of the hollow anode tube is hexagonal, 6 dust accumulation surfaces and 6 dust retention angles can be formed, and the dust accumulation surface and dust retention rate are balanced. If the cross section of the hollow anode tube is more polygonal, more dust accumulation edges can be obtained, but the dust holding rate is lost. In an embodiment of the present invention, the diameter of the tube inscribed circle of the hollow anode tube ranges from 5 mm to 400 mm.

In an embodiment of the present invention, the electric field cathode is installed on the cathode support plate, and the cathode support plate and the electric field anode are connected through an exhaust gas insulation mechanism. In an embodiment of the present invention, the electric field anode includes a first anode part and a second anode part, that is, the first anode part is close to the inlet of the dust removal device, and the second anode part is close to the outlet of the dust removal device. The cathode support plate and the exhaust gas insulation mechanism are between the first anode part and the second anode part, that is, the exhaust gas insulation mechanism is installed in the middle of the ionization electric field or the middle of the electric field cathode, which can play a good supporting role for the electric field cathode. Play a fixed role relative to the electric field anode, keeping the set distance between the electric field cathode and the electric field anode. In the prior art, the support point of the cathode is at the end of the cathode, and it is difficult to maintain the distance between the cathode and the anode. In an embodiment of the present invention, the exhaust gas insulation mechanism is arranged outside the dust removal channel to prevent or reduce dust in the exhaust gas from accumulating on the exhaust gas insulation mechanism, causing the exhaust gas insulation mechanism to breakdown or conduct electricity.

In an embodiment of the present invention, the exhaust gas insulation mechanism uses high-voltage resistant ceramic insulators to insulate the electric field cathode and the electric field anode. The electric field anode is also called a kind of housing.

In an embodiment of the present invention, the first anode part is located before the cathode support plate and the exhaust gas insulation mechanism in the gas flow direction. The first anode part can remove water in the exhaust gas and prevent water from entering the exhaust gas insulation mechanism, causing short circuit of the exhaust gas insulation mechanism. Fire up. In addition, the third anode part can remove a considerable part of the dust in the exhaust gas. When the exhaust gas passes through the exhaust gas insulation mechanism, a considerable part of the dust has been eliminated, reducing the possibility of short circuit caused by the exhaust gas insulation mechanism. In an embodiment of the present invention, the exhaust gas insulation mechanism includes an insulating ceramic column. The design of the first anode part is mainly to protect the insulating ceramic pillars from being polluted by particles in the gas. Once the insulating ceramic pillars are polluted by the gas, the electric field anode and the electric field cathode will be connected, which will invalidate the dust accumulation function of the electric field anode. The design of the first anode part can effectively reduce the pollution of the insulating ceramic pillar and increase the service time of the product. When the exhaust gas flows through the second-stage flow channel, the first anode part and the electric field cathode first contact the polluting gas, and the exhaust gas insulation mechanism contacts the gas to achieve the purpose of first removing dust and then passing the exhaust gas insulation mechanism, reducing the impact on the exhaust gas insulation mechanism The pollution caused by the prolonged cleaning and maintenance cycle, the corresponding electrode insulation support after use. In an embodiment of the present invention, the length of the first anode portion is long enough to remove some dust, reduce dust accumulated on the exhaust gas insulation mechanism and the cathode support plate, and reduce electric shock caused by dust wear. In an embodiment of the present invention, the length of the first anode portion occupies 1/10 to 1/4, 1/4 to 1/3, 1/3 to 1/2, 1/2 to 2/3 of the total length of the electric field anode. 2/3 to 3/4, or 3/4 to 9/10.

In an embodiment of the present invention, the second anode part is located behind the cathode support plate and the exhaust gas insulation mechanism in the exhaust gas flow direction. The second anode part includes a dust accumulation section and a reserved dust accumulation section. Among them, the dust accumulation section uses static electricity to adsorb particulate matter in the exhaust gas. The dust accumulation section is to increase the dust accumulation area and prolong the use time of the exhaust gas electric field device. The reserved dust section can provide failure protection for the dust section. The dust accumulation section is reserved to further increase the dust accumulation area under the premise of meeting the design dust removal requirements. The dust accumulation section is reserved to supplement the dust accumulation in the front section. In an embodiment of the present invention, the reserved dust accumulation section and the first anode part can use different power sources.

In an embodiment of the present invention, due to the extremely high potential difference between the electric field cathode and the electric field anode, in order to prevent the electric field cathode and the electric field anode from conducting, the exhaust gas insulation mechanism is arranged in the second-stage flow channel between the electric field cathode and the electric field anode. outer. Therefore, the exhaust gas insulation mechanism is suspended outside the electric field anode. In an embodiment of the present invention, the exhaust gas insulation mechanism can be made of non-conductor temperature-resistant materials, such as ceramics, glass, etc. In an embodiment of the present invention, the material insulation requirement for completely airtight air-free insulation requires insulation thickness> 0.3 mm/kv; air insulation requirement> 1.4 mm/kv. The insulation distance can be set at more than 1.4 times the distance between the electric field cathode and the electric field anode. In an embodiment of the present invention, the exhaust gas insulation mechanism uses ceramics, and the surface is glazed; adhesives or organic materials cannot be used for filling connections, and the temperature resistance is greater than 350 degrees Celsius.

In an embodiment of the present invention, the exhaust gas insulation mechanism includes an insulation part and a heat insulation part. In order to make the exhaust gas insulation mechanism have anti-fouling function, the material of the insulation part is ceramic material or glass material. In an embodiment of the present invention, the insulating part may be an umbrella-shaped string of ceramic pillars or glass pillars with glaze on the inside and outside of the umbrella. The distance between the outer edge of the umbrella string ceramic column or the glass column and the electric field anode is greater than or equal to 1.4 times the electric field distance, that is, greater than or equal to 1.4 times the electrode spacing. The sum of the pitches of umbrella protrusions of the umbrella string ceramic columns or glass columns is greater than or equal to 1.4 times the insulation pitch of the umbrella string ceramic columns. The total inner depth of the umbrella side of the umbrella string ceramic column or the glass column is greater than or equal to 1.4 times the insulation distance of the umbrella string ceramic column. The insulating part can also be a columnar string of ceramic columns or glass columns with glaze on the inside and outside of the columns. In an embodiment of the present invention, the insulating portion may also be tower-shaped.

In an embodiment of the present invention, a heating rod is arranged in the insulating part, and when the temperature around the insulating part approaches the dew point, the heating rod is activated and heated. Due to the temperature difference between the inside and outside of the insulating part during use, condensation is likely to occur on the inside and outside of the insulating part. The outer surface of the insulating part may spontaneously or be heated by gas to generate high temperature, and necessary isolation protection is required to prevent burns. The heat insulation part includes a protective enclosure and a denitration purification reaction chamber located outside the second insulation part. In an embodiment of the present invention, the end of the insulating part that needs condensation location also needs to be insulated to prevent the environment and the heat dissipation high temperature heating condensation component.

In an embodiment of the present invention, the lead-out line of the power supply of the exhaust electric field device is connected through the wall using umbrella-shaped string ceramic pillars or glass pillars, using flexible contacts to connect the cathode support plate in the wall, and plugging and unplugging the sealed insulating protective wiring cap outside the wall , The insulation distance between the lead wire and the wall conductor and the wall is greater than the ceramic insulation distance of the umbrella string ceramic column or glass column. In an embodiment of the present invention, the high voltage part removes the lead wire and is directly installed on the end to ensure safety. The overall external insulation of the high voltage module is protected by ip68, and the medium is used for heat exchange and heat dissipation.

In an embodiment of the present invention, the electric field anode and the electric field cathode are respectively electrically connected to the two electrodes of the power supply. The voltage applied to the electric field anode and the electric field cathode needs to select an appropriate voltage level. The specific voltage level selected depends on the volume, temperature resistance, and dust holding rate of the exhaust electric field device. For example, the voltage is from 1kv to 50kv; first consider the temperature resistance conditions in the design, the parameters of the pole spacing and temperature: 1MM<30 degrees, the dust area is greater than 0.1 square / thousand cubic meters / hour, and the electric field length is greater than 5 of the inscribed circle of a single tube The air flow velocity of the control electric field is less than 9 m/s. In an embodiment of the present invention, the electric field anode is composed of a second hollow anode tube and has a honeycomb shape. The shape of the second hollow anode tube port may be circular or polygonal. In an embodiment of the present invention, the inscribed circle of the second hollow anode tube ranges from 5-400mm, and the corresponding voltage is between 0.1-120kv, and the corresponding current of the second hollow anode tube is between 0.1-30A; The tangent circle corresponds to different corona voltages, about 1KV/1MM.

In an embodiment of the present invention, the exhaust electric field device includes a second electric field stage, and the second electric field stage includes a plurality of second electric field generating units, and there may be one or more second electric field generating units. The second electric field generating unit is also called the second dust collecting unit. The second dust collecting unit includes the above-mentioned electric field anode and the electric field cathode. There are one or more second dust collecting units. When there are multiple second electric field levels, the dust collection efficiency of the exhaust electric field device can be effectively improved. In the same second electric field level, each electric field anode has the same polarity, and each electric field cathode has the same polarity. And when there are multiple second electric field levels, each second electric field level is connected in series. In an embodiment of the present invention, the exhaust electric field device further includes a plurality of connecting shells, and the series-connected second electric field stages are connected by the connecting shells; the distance between the second electric field stages of two adjacent stages is greater than 1.4 times of the pole pitch.

The inventor of the present invention has discovered through research that the shortcomings of the electric field dust removal device in the prior art are caused by electric field coupling. The invention can significantly reduce the size (namely volume) of the electric field dust removal device by reducing the number of electric field couplings. For example, the size of the ionization dust removal device provided by the present invention is about one-fifth of the size of the existing ionization dust removal device. The reason is that in order to obtain an acceptable particle removal rate, the gas flow rate in the existing ionization dust removal device is set to about 1m/s, and the present invention can still obtain a higher gas flow rate when the gas flow rate is increased to 6m/s. Particle removal rate. When processing a given flow of gas, as the gas velocity increases, the size of the electric field dust removal device can be reduced.

In addition, the present invention can significantly improve the particle removal efficiency. For example, when the gas flow rate is about 1m/s, the prior art electric field dust removal device can remove about 70% of the particulate matter in the engine exhaust, but the present invention can remove about 99% of the particulate matter, even when the gas flow rate is 6m/s . Therefore, the present invention can meet the latest emission standards.

Since the inventor discovered the effect of electric field coupling and found a method to reduce the number of times of electric field coupling, the present invention achieved the above unexpected results. Therefore, the present invention can be used to manufacture an electric field dust removal device suitable for vehicles.

The method for reducing the number of electric field coupling provided by the present invention is as follows:

In an embodiment of the present invention, an asymmetric structure is adopted between the electric field cathode and the electric field anode. In a symmetric electric field, polar particles are subjected to a force of the same magnitude but opposite in direction, and the polar particles reciprocate in the electric field; in an asymmetric electric field, the polar particles are subjected to two different forces, and the polar particles act towards Move in the direction of great force to avoid coupling.

In some embodiments of the present invention, there is provided a system for treating VOCs in engine exhaust gas, which includes: an inlet, an outlet, and a flow channel between the inlet and the outlet; and an ultraviolet device, an exhaust electric field device, and the ultraviolet device , The exhaust electric field device is arranged along the flow channel in sequence from the inlet to the outlet; the exhaust electric field device includes: an electric field device inlet, an electric field device outlet, an electric field cathode and an electric field anode, the electric field cathode and the electric field anode are used To generate an ionization dust removal electric field; the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is 1.667:1 to 1680:1.

In an embodiment of the present invention, the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is 6.67:1 to 56.67:1.

In an embodiment of the present invention, the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is such that the coupling times of the ionization dust removal electric field are ≤3.

In an embodiment of the present invention, the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode, the distance between the electric field anode and the electric field cathode, the length of the electric field anode, and the The length of the electric field cathode makes the coupling times of the ionization dust removal electric field≤3.

In an embodiment of the present invention, a method for processing VOCs in engine exhaust gas is provided, which includes the following steps:

The product after UV treatment is subjected to electric field dust removal treatment to remove particles in the product after UV treatment;

The electric field dust removal treatment further includes a method for reducing the coupling of the dust removal electric field, and the method for reducing the coupling of the dust removal electric field includes the following steps: including selecting the ratio of the dust collecting area of the electric field anode to the discharge area of the electric field cathode to make the electric field coupling Times≤3.

In an embodiment of the present invention, the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is selected to be 1.667:1 to 1680:1. In an embodiment of the present invention, the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is selected to be 6.67:1 to 5.67:1. In an embodiment of the present invention, the diameter of the electric field cathode is selected to be 1-3 mm, and the distance between the electric field anode and the electric field cathode is 2.5-139.9 mm; the dust accumulation area of the electric field anode and the The ratio of the discharge area of the electric field cathode is 1.667:1 to 1680:1.

In some embodiments of the present invention, there is provided a system for treating VOCs in engine exhaust gas, which includes: an inlet, an outlet, and a flow channel between the inlet and the outlet; and an ultraviolet device, an exhaust electric field device, and the ultraviolet device , The exhaust electric field device is arranged along the flow channel in sequence from the inlet to the outlet; the exhaust electric field device includes: an electric field device inlet, an electric field device outlet, an electric field cathode and an electric field anode, the electric field cathode and the electric field anode are used To generate an ionization dust removal electric field; the length of the electric field anode is 10-180mm.

In an embodiment of the present invention, the length of the electric field anode is 60-180 mm.

In an embodiment of the present invention, the length of the anode of the electric field is such that the coupling times of the ionization dust removal electric field are ≤3.

The electric field dust removal treatment further includes a method for reducing the coupling of the dust removal electric field. The method for reducing the coupling of the dust removal electric field includes the following steps: including selecting the length of the electric field anode so that the number of electric field couplings is less than or equal to 3.

In an embodiment of the present invention, it includes selecting the length of the electric field anode to be 10-180 mm.

In an embodiment of the present invention, it includes selecting the length of the electric field anode to be 60-180 mm.

In some embodiments of the present invention, there is provided a system for treating VOCs in engine exhaust gas, which includes: an inlet, an outlet, and a flow channel between the inlet and the outlet; and an ultraviolet device, an exhaust electric field device, and the ultraviolet device , The exhaust electric field device is arranged along the flow channel in sequence from the inlet to the outlet; the exhaust electric field device includes: an electric field device inlet, an electric field device outlet, an electric field cathode and an electric field anode, which are used for the electric field cathode and the electric field anode To generate an ionization dust removal electric field; the length of the electric field cathode is 30-180mm.

In an embodiment of the present invention, the length of the electric field cathode is 54-176 mm.

The electric field dust removal treatment further includes a method for reducing the coupling of the dust removal electric field, and the method for reducing the coupling of the dust removal electric field includes the following steps:

Including the selection of the electric field cathode length so that the number of electric field coupling ≤ 3.

In an embodiment of the present invention, it includes selecting the electric field cathode length to be 30-180 mm.

In an embodiment of the present invention, it includes selecting the length of the electric field cathode to be 54-176 mm.

In some embodiments of the present invention, there is provided a system for treating VOCs in engine exhaust gas, which includes: an inlet, an outlet, and a flow channel between the inlet and the outlet; and an ultraviolet device, an exhaust electric field device, and the ultraviolet device , The exhaust electric field device is arranged along the flow channel in sequence from the inlet to the outlet; the exhaust electric field device includes: an electric field device inlet, an electric field device outlet, an electric field cathode and an electric field anode, the electric field cathode and the electric field anode are used To generate an ionization dust removal electric field; the distance between the electric field anode and the electric field cathode is less than 150 mm.

In an embodiment of the present invention, the distance between the electric field anode and the electric field cathode is 2.5-139.9 mm.

In an embodiment of the present invention, the distance between the electric field anode and the electric field cathode is 5-100 mm.

In an embodiment of the present invention, the distance between the electric field anode and the electric field cathode is such that the coupling times of the ionization dust removal electric field are ≤3.

It includes selecting the distance between the electric field anode and the electric field cathode so that the number of electric field couplings is less than or equal to 3.

In an embodiment of the present invention, the distance between the electric field anode and the electric field cathode is selected to be 2.5-139.9 mm.

In an embodiment of the present invention, the distance between the electric field anode and the electric field cathode is selected to be 5-100 mm.

An ionization dust removal electric field is formed between the electric field cathode and the electric field anode of the exhaust electric field device of the present invention. In order to reduce the electric field coupling of the ionization dust removal electric field, in an embodiment of the present invention, the method for reducing electric field coupling includes the following steps: selecting the ratio of the dust collection area of the electric field anode to the discharge area of the electric field cathode, so that the number of electric field couplings ≤3 . In an embodiment of the present invention, the ratio of the dust collecting area of the electric field anode to the discharge area of the electric field cathode may be: 1.667:1 to 1680:1; 3.334:1 to 13.34:1; 6.67:1-56.67:1; 13.34: 1-28.33:1. This embodiment selects the dust collecting area of the electric field anode with a relatively large area and the discharge area of the relatively small electric field cathode. The specific selection of the above area ratio can reduce the discharge area of the electric field cathode, reduce the suction force, and expand the dust collecting area of the electric field anode. , Expand the suction, that is, the asymmetric electrode suction between the electric field cathode and the electric field anode, so that the charged dust falls on the dust collecting surface of the electric field anode, although the polarity is changed, it can no longer be sucked away by the electric field cathode, reducing the electric field coupling to achieve The number of electric field coupling ≤ 3. That is, when the electric field distance is less than 150mm, the number of electric field couplings is less than or equal to 3, the electric field energy consumption is low, and the electric field can reduce the coupling consumption of aerosol, water mist, oil mist, loose and smooth particles, and save electric field power by 30-50%. The dust collection area refers to the area of the working surface of the electric field anode. For example, if the electric field anode is a hollow regular hexagon tube, the dust collection area is the inner surface area of the hollow regular hexagon tube, and the dust collection area is also called the dust accumulation area. The discharge area refers to the area of the working surface of the electric field cathode. For example, if the electric field cathode is rod-shaped, the discharge area is the rod-shaped outer surface area.

In an embodiment of the present invention, the length of the electric field anode can be 10 to 180 mm, 10 to 20 mm, 20 to 30 mm, 60 to 180 mm, 30 to 40 mm, 40 to 50 mm, 50 to 60 mm, 60 to 70 mm, 70 to 80 mm, 80 mm. ～90mm, 90～100mm, 100～110mm, 110～120mm, 120～130mm, 130～140mm, 140～150mm, 150～160mm, 160～170mm, 170～180mm, 60mm, 180mm, 10mm or 30mm. The length of the electric field anode refers to the minimum length from one end to the other end of the working surface of the electric field anode. Choosing this length of the electric field anode can effectively reduce the electric field coupling.

In an embodiment of the present invention, the length of the electric field anode can be 10~90mm, 15~20mm, 20~25mm, 25~30mm, 30~35mm, 35~40mm, 40~45mm, 45~50mm, 50~55mm, 55mm ～60mm, 60～65mm, 65～70mm, 70～75mm, 75～80mm, 80～85mm or 85～90mm. The design of this length can make the electric field anode and exhaust electric field device have high temperature resistance characteristics, and make the exhaust electric field device It has high efficiency dust collection ability under high temperature impact.

In an embodiment of the present invention, the length of the electric field cathode can be 30～180mm, 54～176mm, 30～40mm, 40～50mm, 50～54mm, 54～60mm, 60～70mm, 70～80mm, 80～90mm, 90mm. ~100mm, 100-110mm, 110-120mm, 120-130mm, 130-140mm, 140-150mm, 150-160mm, 160-170mm, 170-176mm, 170-180mm, 54mm, 180mm, or 30mm. The length of the electric field cathode refers to the minimum length from one end to the other end of the working surface of the electric field cathode. Choosing this length of the electric field cathode can effectively reduce the electric field coupling.

In an embodiment of the present invention, the length of the electric field cathode may be 10 to 90 mm, 15 to 20 mm, 20 to 25 mm, 25 to 30 mm, 30 to 35 mm, 35 to 40 mm, 40 to 45 mm, 45 to 50 mm, 50 to 55 mm, 55 mm. ～60mm, 60～65mm, 65～70mm, 70～75mm, 75～80mm, 80～85mm or 85～90mm, the design of this length can make the electric field cathode and exhaust electric field device have high temperature resistance characteristics, and make the exhaust electric field device It has high efficiency dust collection ability under high temperature impact. Among them, when the electric field temperature is 200℃, the corresponding dust collection efficiency is 99.9%; when the electric field temperature is 400℃, the corresponding dust collection efficiency is 90%; when the electric field temperature is 500℃, the corresponding dust collection efficiency is 50 %.

In an embodiment of the present invention, the distance between the electric field anode and the electric field cathode may be 5-30mm, 2.5-139.9mm, 9.9-139.9mm, 2.5-9.9mm, 9.9-20mm, 20-30mm, 30-40mm, 40mm. ～50mm, 50～60mm, 60～70mm, 70～80mm, 80～90mm, 90～100mm, 100～110mm, 110～120mm, 120～130mm, 130～139.9mm, 9.9mm, 139.9mm, or 2.5mm. The distance between the anode of the electric field and the cathode of the electric field is also referred to as the electrode pitch. The pole distance specifically refers to the minimum vertical distance between the working surfaces of the electric field anode and the electric field cathode. The selection of this pole spacing can effectively reduce the electric field coupling and make the exhaust electric field device have high temperature resistance characteristics.

In an embodiment of the present invention, the diameter of the electric field cathode is 1-3 mm, and the distance between the electric field anode and the electric field cathode is 2.5-139.9 mm; the dust accumulation area of the electric field anode and the electric field cathode The ratio of the discharge area is 1.667:1 to 1680:1.

For the exhaust gas system, in one embodiment, the electric field dust removal treatment method provided by the present invention further includes: a method for reducing the coupling of the exhaust gas dust removal electric field, including the following steps:

The tail gas ionization dust removal electric field generated by the tail gas through the electric field anode and the electric field cathode;

The electric field anode or/and the electric field cathode are selected.

In an embodiment of the present invention, the size of the electric field anode or/and the electric field cathode is selected such that the number of electric field couplings is ≤3.

Specifically, the ratio of the dust collection area of the electric field anode to the discharge area of the electric field cathode is selected. Preferably, the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is selected to be 1.667:1 to 1680:1.

More preferably, the ratio of the dust accumulation area of the electric field anode to the discharge area of the exhaust dust removal electric field cathode is selected to be 6.67:1 to 56.67:1.

Preferably, the distance between the electric field anode and the electric field cathode is selected to be less than 150 mm.

Preferably, the distance between the electric field anode and the electric field cathode is selected to be 2.5 to 139.9 mm. More preferably, the distance between the electric field anode and the electric field cathode is selected to be 5.0 to 100 mm.

Preferably, the length of the electric field anode is selected to be 10 to 180 mm. More preferably, the length of the electric field anode is selected to be 60-180 mm.

Preferably, the length of the electric field cathode is selected to be 30-180 mm. More preferably, the length of the electric field cathode is selected to be 54-176 mm.

In some embodiments of the present invention, a gas treatment system for VOCs in engine exhaust is provided, which includes: an inlet, an outlet, and a flow channel between the inlet and the outlet; and an ultraviolet device, an exhaust electric field device, and the ultraviolet device , The exhaust electric field device is arranged along the flow channel in sequence from the inlet to the outlet; the exhaust electric field device includes: an electric field device inlet, an electric field device outlet, an electric field cathode and an electric field anode, the electric field cathode and the electric field anode are used In order to generate an ionization dust removal electric field; the electric field device further includes an auxiliary electric field unit for generating an auxiliary electric field that is not parallel to the ionization dust removal electric field.

In some embodiments of the present invention, a gas treatment system for VOCs in engine exhaust is provided, which includes: an inlet, an outlet, and a flow channel between the inlet and the outlet; and an ultraviolet device, an exhaust electric field device, and the ultraviolet device , The exhaust electric field device is arranged along the flow channel in sequence from the inlet to the outlet; the exhaust electric field device includes: an electric field device inlet, an electric field device outlet, an electric field cathode and an electric field anode, the electric field cathode and the electric field anode are used In order to generate an ionization dust removal electric field; the electric field device further includes an auxiliary electric field unit, the ionization dust removal electric field includes a flow channel, and the auxiliary electric field unit is used to generate an auxiliary electric field that is not perpendicular to the flow channel.

In an embodiment of the present invention, the auxiliary electric field unit includes a first electrode, and the first electrode of the auxiliary electric field unit is disposed at or near the entrance of the ionization dust removal electric field.

In an embodiment of the present invention, the first electrode is a cathode.

In an embodiment of the present invention, the first electrode of the auxiliary electric field unit is an extension of the electric field cathode.

In an embodiment of the present invention, the first electrode of the auxiliary electric field unit and the electric field anode have an included angle α, and 0°<α≤125°, or 45°≤α≤125°, or 60°≤α ≤100°, or α=90°.

In an embodiment of the present invention, the auxiliary electric field unit includes a second electrode, and the second electrode of the auxiliary electric field unit is arranged at or near the outlet of the ionization dust removal electric field.

In an embodiment of the present invention, the second electrode is an anode.

In an embodiment of the present invention, the second electrode of the auxiliary electric field unit is an extension of the electric field anode.

In an embodiment of the present invention, the second electrode of the auxiliary electric field unit and the electric field cathode have an included angle α, and 0°<α≤125°, or 45°≤α≤125°, or 60°≤α ≤100°, or α=90°.

In an embodiment of the present invention, the electrode of the auxiliary electric field and the electrode of the ionization dust removal electric field are arranged independently.

In some embodiments of the present invention, the electric field dust removal treatment method provided by the present invention further includes a method of providing an auxiliary electric field, including the following steps:

Pass the gas through a flow channel;

An auxiliary electric field is generated in the flow channel, and the auxiliary electric field is not perpendicular to the flow channel.

Wherein, the auxiliary electric field ionizes the gas.

In an embodiment of the present invention, the auxiliary electric field is generated by the auxiliary electric field unit, and the structure of the auxiliary electric field unit is the same as that of the auxiliary electric field unit in the electric field device.

The ionization dust removal electric field between the electric field anode and the electric field cathode in the exhaust electric field device of the present invention is also called the third electric field. In an embodiment of the present invention, a fourth electric field that is not parallel to the third electric field is formed between the electric field anode and the electric field cathode. In another embodiment of the present invention, the flow channel of the fourth electric field and the ionization dust removal electric field are not perpendicular. The fourth electric field is also called an auxiliary electric field and can be formed by one or two auxiliary electrodes. When the fourth electric field is formed by an auxiliary electrode, the auxiliary electrode can be placed at the inlet or outlet of the ionization electric field, and the auxiliary electrode can be charged with a negative or positive potential. Wherein, when the auxiliary electrode is a cathode, it is arranged at or near the entrance of the ionization dust removal electric field; the auxiliary electrode and the electric field anode have an angle α, and 0°<α≤125°, or 45°≤ α≤125°, or 60°≤α≤100°, or α=90°. When the auxiliary electrode is the anode, it is arranged at or near the outlet of the ionization dust removal electric field; the auxiliary electrode and the electric field cathode have an angle α, and 0°<α≤125°, or 45°≤α≤ 125°, or 60°≤α≤100°, or α=90°. When the fourth electric field is formed by two auxiliary electrodes, one of the auxiliary electrodes can have a negative potential and the other auxiliary electrode can have a positive potential; one auxiliary electrode can be placed at the entrance of the ionization dust removal electric field, and the other auxiliary electrode can be placed at the ionization dust removal The exit of the electric field. In addition, the auxiliary electrode may be a part of the electric field cathode or the electric field anode, that is, the auxiliary electrode may be an extension of the electric field cathode or the electric field anode, and the length of the electric field cathode and the electric field anode are different. The auxiliary electrode may also be a separate electrode, that is, the auxiliary electrode may not be a part of the electric field cathode or the electric field anode. In this case, the voltage of the fourth electric field is different from the voltage of the third electric field and can be controlled separately according to the working conditions.

In an embodiment of the present invention, the engine exhaust dust removal system further includes a water removal device for removing liquid water before the entrance of the electric field device.

In an embodiment of the present invention, when the exhaust gas temperature or the engine temperature is lower than a certain temperature, the engine exhaust gas may contain liquid water, and the water removing device removes the liquid water in the exhaust gas.

In an embodiment of the present invention, the certain temperature is above 90°C and below 100°C.

In an embodiment of the present invention, the certain temperature is above 80°C and below 90°C.

In an embodiment of the present invention, the certain temperature is below 80°C.

In an embodiment of the present invention, the electric field dust removal treatment method provided by the present invention further includes: a tail gas dust removal method, including the following steps: when the temperature of the tail gas is lower than 100°C, liquid water in the tail gas is removed, and then ionization is used to remove dust.

In an embodiment of the present invention, when the temperature of the exhaust gas is ≥100°C, the exhaust gas is ionized to remove dust.

In an embodiment of the present invention, when the exhaust gas temperature is ≤90°C, the liquid water in the exhaust gas is removed, and then ionized to remove dust.

In an embodiment of the present invention, when the exhaust gas temperature is less than or equal to 80°C, the liquid water in the exhaust gas is removed, and then ionization is performed to remove dust.

In an embodiment of the present invention, when the exhaust gas temperature is ≤70°C, the liquid water in the exhaust gas is removed, and then ionized to remove dust.

In an embodiment of the present invention, the liquid water in the tail gas is removed by the electrocoagulation defogging method, and then ionization is used to remove dust.

Those skilled in the art have not recognized the following technical problem: when the exhaust gas or engine temperature is low, there will be liquid water in the exhaust gas, which will be adsorbed on the electric field cathode and electric field anode, resulting in uneven discharge and ignition of the exhaust gas ionization dust removal electric field. The inventor found this problem and proposed that the engine exhaust dust removal system is equipped with a water removal device to remove liquid water before the entrance of the electric field device. The liquid water has conductivity and will shorten the ionization distance, resulting in uneven discharge of the exhaust gas ionization dust removal electric field. Lead to electrode breakdown. When the engine is cold-started, the water removal device removes water droplets or liquid water in the tail gas before the tail gas enters the entrance of the electric field device, thereby reducing water droplets or liquid water in the tail gas, and reducing the uneven discharge of the tail gas ionization dust removal electric field and the electric field The cathode and the anode of the electric field are broken down, thereby improving the efficiency of ionization and dust removal, and achieving unexpected technical effects. The water removal device is not particularly limited, and the present invention can be used to remove liquid water in the tail gas in the prior art.

The following specific examples are used to further illustrate the system and method for processing VOCs in engine exhaust of the present invention.

Example 1

The VOCs treatment system in engine exhaust described in this embodiment includes an exhaust gas treatment device, and the exhaust gas treatment device is used to treat exhaust gas to be discharged into the atmosphere after being treated by an ultraviolet device.

Please refer to FIG. 1, which shows a schematic structural diagram of an exhaust gas treatment device in an embodiment. As shown in FIG. 1, the exhaust gas treatment device 102 includes an exhaust gas electric field device 1021, an exhaust gas insulation mechanism 1022, a water removal device.

The exhaust electric field device 1021 includes an electric field anode 10211 and an electric field cathode 10212 arranged in the electric field anode 10211. An asymmetric electrostatic field is formed between the electric field anode 10211 and the electric field cathode 10212, wherein the gas to be contained in particulate matter passes through the exhaust port After entering the exhaust electric field device 1021, the electric field cathode 10212 discharges and ionizes the gas, so that the particles obtain a negative charge, move to the electric field anode 10211, and deposit on the electric field cathode 10212.

Specifically, the inside of the electric field cathode 10212 is composed of a honeycomb-shaped and hollow anode tube bundle group, and the shape of the port of the anode tube bundle is a hexagon.

The electric field cathode 10212 includes a plurality of electrode rods, each of which penetrates each anode tube bundle in the anode tube bundle group one by one, wherein the shape of the electrode rods is needle-like, polygonal, burr-like, and threaded rod. Shaped or columnar.

The ratio of the dust collecting area of the electric field anode 10211 to the discharge area of the electric field cathode 10212 is 1680:1, the distance between the electric field anode 10211 and the electric field cathode 10212 is 9.9 mm, the electric field anode 10211 length is 60 mm, and the electric field cathode 10212 length It is 54mm.

In this embodiment, the inlet end of the electric field cathode 10212 is lower than the inlet end of the electric field anode 10211, and the outlet end of the electric field cathode 10212 is flush with the outlet end of the electric field anode 10211. There is an angle α between the inlet end of the electric field cathode 10212 and the inlet end of the electric field anode 10211, and α=90°, so that an accelerating electric field is formed inside the exhaust electric field device 1021, which can save more to be processed The substance is collected.

The exhaust gas insulation mechanism 1022 suspended from the airway includes an insulation part and a heat insulation part. The insulating part is made of ceramic material or glass material. The insulating part is an umbrella-shaped string of ceramic pillars, and the umbrella is covered with glaze. Please refer to FIG. 2, which shows a schematic structural diagram of an umbrella-shaped exhaust gas insulation mechanism in an embodiment.

As shown in FIG. 1, in an embodiment of the present invention, the electric field cathode is mounted on the cathode support plate 10213, and the cathode support plate 10213 and the electric field anode 10211 are connected through an exhaust gas insulation mechanism 1022. In an embodiment of the present invention, the electric field anode 10211 includes a first anode portion 102112 and a second anode portion 102111, that is, the first anode portion 102112 is close to the inlet of the dust removal device, and the second anode portion 102111 is close to the outlet of the dust removal device. The cathode support plate 10213 and the exhaust gas insulation mechanism 1022 are located between the first anode portion 102112 and the second anode portion 102111, that is, the exhaust gas insulation mechanism 1022 is installed in the middle of the ionization electric field or the electric field cathode 10212, which can play a good role in the electric field cathode 10212. It supports and fixes the electric field cathode 10212 relative to the electric field anode 10211, and keeps a set distance between the electric field cathode 10212 and the electric field anode 10211.

The dewatering device is used to remove liquid water before the entrance of the electric field device. When the exhaust gas temperature is lower than 100° C., the dewatering device removes the liquid water in the exhaust gas, and the dewatering device is an electrocoagulation defogging device.

Example 2

As shown in Figure 3, the engine exhaust dust removal system includes a water removal device 207 and an exhaust electric field device. The exhaust electric field device includes an electric field anode 10211 and an electric field cathode 10212, and the electric field anode 10211 and the electric field cathode 10212 are used to generate an exhaust gas ionization and dust removal electric field. The water removal device 207 is used to remove liquid water before the entrance of the electric field device. When the exhaust gas temperature is lower than 100°C, the water removal device removes the liquid water in the tail gas. The water removal device 207 is an electrocoagulation device. The direction of the arrow in the figure is the direction of exhaust gas flow.

In this embodiment, the product after the ultraviolet device has processed the VOCs in the exhaust gas of the engine is processed. The processing method includes: a method for removing dust from the exhaust gas, including the following steps: when the temperature of the exhaust gas is lower than 100°C, the liquid water in the exhaust gas is removed, and then ionization and dust removal , Wherein the electrocoagulation defogging method is used to remove the liquid water in the tail gas. The tail gas is the tail gas during the cold start of the gasoline engine, which reduces the water droplets in the tail gas, that is, liquid water, and reduces the uneven discharge of the tail gas ionization and dust removal electric field and the electric field cathode and The anode breakdown of the electric field improves the ionization dust removal efficiency. The ionization dust removal efficiency is more than 99.9%, and the ionization dust removal efficiency of the dust removal method without removing the liquid water in the tail gas is less than 70%. Therefore, when the exhaust gas temperature is lower than 100°C, the liquid water in the exhaust gas is removed, and then the liquid water is ionized to reduce the water droplets in the exhaust gas, which reduces the uneven discharge of the exhaust gas ionization and dust removal electric field and the breakdown of the electric field cathode and the electric field anode. Ionization dust removal efficiency.

Example 3

In this embodiment, the electric field generating unit is applied to an exhaust electric field device, as shown in FIG. 4, including an electric field anode 4051 and an electric field cathode 4052 for forming an exhaust ionization and dust removal electric field. The electric field anode 4051 and the electric field cathode 4052 are respectively connected to the two power supplies. Each electrode is electrically connected, the power source is a DC power source, and the electric field anode 4051 and the electric field cathode 4052 are electrically connected to the anode and cathode of the DC power source, respectively. In this embodiment, the electric field anode 4051 has a positive electric potential, and the electric field cathode 4052 has a negative electric potential.

The DC power supply in this embodiment may specifically be a DC high-voltage power supply. A tail gas ionization and dust removal electric field is formed between the electric field anode 4051 and the electric field cathode 4052, and the tail gas ionization and dust removal electric field is an electrostatic field.

As shown in FIGS. 4, 5, and 6, in this embodiment, the electric field anode 4051 has a hollow regular hexagonal tube shape, the electric field cathode 4052 has a rod shape, and the electric field cathode 4052 penetrates the electric field anode 4051.

In this embodiment, the product after the ultraviolet device has processed the VOCs in the engine exhaust gas is processed. The processing method includes: a method of reducing electric field coupling, including the following steps: selecting the ratio of the dust collecting area of the electric field anode 4051 to the discharge area of the electric field cathode 4052 is 6.67 :1. The distance L3 between the electric field anode 4051 and the electric field cathode 4052 is 9.9 mm, the electric field anode 4051 length L1 is 60 mm, and the electric field cathode 4052 length L2 is 54 mm. The electric field anode 4051 includes an exhaust fluid channel, and the exhaust fluid channel includes At the inlet and outlet ends, the electric field cathode 4052 is placed in the exhaust fluid channel, the electric field cathode 4052 extends in the direction of the electric field anode exhaust fluid channel, and the inlet end of the electric field anode 4051 is aligned with the near inlet end of the electric field cathode 4052 Flat, the exit end of the electric field anode 4051 and the near exit end of the electric field cathode 4052 have an angle α, and α=118°, and under the action of the electric field anode 4051 and the electric field cathode 4052, more substances to be processed can be removed Collected, the number of electric field couplings is less than or equal to 3, which can reduce the coupling consumption of aerosol, water mist, oil mist, and loose smooth particles by the electric field, and save the electric energy of the electric field by 30-50%.

The exhaust electric field device in this embodiment includes electric field stages composed of a plurality of the above-mentioned electric field generating units, and there are multiple electric field stages so as to effectively improve the dust collection efficiency of the exhaust electric field device by using multiple dust collecting units. In the same electric field level, each tail gas ionization dust removal electric field anode has the same polarity, and each tail gas ionization dust removal electric field cathode has the same polarity.

The electric field stages of the plurality of electric field stages are connected in series, and the series electric field stages are connected by a connecting shell. The distance between the electric field stages of two adjacent stages is greater than 1.4 times of the pole spacing. As shown in FIG. 7, the electric field has two levels, namely, the first electric field 4053 and the second electric field 4054. The first electric field 4053 and the second electric field 4054 are connected in series through the connecting housing 4055.

In this embodiment, the above-mentioned substance to be processed may be granular dust.

In this embodiment, the above-mentioned gas is the product after the ultraviolet device treats VOCs in engine exhaust.

Example 4

In this embodiment, the electric field anode 4051 has a hollow regular hexagonal tube shape, the electric field cathode 4052 has a rod shape, and the electric field cathode 4052 penetrates the electric field anode 4051.

This embodiment treats the product after the ultraviolet device treats the VOCs in the engine exhaust. The treatment method includes: a method of reducing electric field coupling, including the following steps: selecting the ratio of the dust collecting area of the electric field anode 4051 to the discharge area of the electric field cathode 4052 to 1680 :1. The distance between the electric field anode 4051 and the electric field cathode 4052 is 139.9 mm, the electric field anode 4051 is 180 mm in length, and the electric field cathode 4052 is 180 mm in length. The electric field anode 4051 includes an exhaust fluid channel, and the exhaust fluid channel includes an inlet end and At the outlet end, the electric field cathode 4052 is placed in the exhaust fluid channel, the electric field cathode 4052 extends along the direction of the electric field anode exhaust fluid channel, and the inlet end of the electric field anode 4051 is flush with the near inlet end of the electric field cathode 4052. The exit end of the anode 4051 is flush with the near exit end of the electric field cathode 4052. Under the action of the electric field anode 4051 and the electric field cathode 4052, more materials to be processed can be collected, and the number of electric field couplings ≤ 3, which can reduce the electric field The coupling consumption of aerosol, water mist, oil mist, and loose and smooth particles saves 20-40% of the electric energy of the electric field.

Example 5

This embodiment treats the product after the ultraviolet device treats VOCs in the engine exhaust. The treatment method includes: a method of reducing electric field coupling, including the following steps: selecting the ratio of the dust collecting area of the electric field anode 4051 to the discharge area of the electric field cathode 4052 to 1.667 :1. The distance between the electric field anode 4051 and the electric field cathode 4052 is 2.4mm, the electric field anode 4051 is 30mm in length, and the electric field cathode 4052 is 30mm in length. The electric field anode 4051 includes an exhaust fluid channel, and the exhaust fluid channel includes an inlet end and At the outlet end, the electric field cathode 4052 is placed in the exhaust fluid channel, the electric field cathode 4052 extends along the direction of the electric field anode exhaust fluid channel, and the inlet end of the electric field anode 4051 is flush with the near inlet end of the electric field cathode 4052. The exit end of the anode 4051 is flush with the near exit end of the electric field cathode 4052. Under the action of the electric field anode 4051 and the electric field cathode 4052, more materials to be processed can be collected, and the number of electric field couplings ≤ 3, which can reduce the electric field The coupling consumption of aerosol, water mist, oil mist, loose and smooth particles can save 10-30% of electric energy in the electric field.

Example 6

As shown in Figures 4, 5 and 6, the electric field anode 4051 in this embodiment is a hollow regular hexagonal tube, the electric field cathode 4052 is rod-shaped, and the electric field cathode 4052 penetrates the electric field anode 4051. The dust collection of the electric field anode 4051 The ratio of the area to the discharge area of the electric field cathode 4052 is 6.67:1, the distance L3 between the electric field anode 4051 and the electric field cathode 4052 is 9.9 mm, the electric field anode 4051 length L1 is 60 mm, and the electric field cathode 4052 length L2 is 54 mm. The electric field anode 4051 includes an exhaust gas fluid channel, the exhaust fluid channel includes an inlet end and an outlet end, the electric field cathode 4052 is placed in the exhaust fluid channel, and the electric field cathode 4052 extends along the direction of the electric field anode exhaust fluid channel. The entrance end of the anode 4051 is flush with the near entrance end of the electric field cathode 4052. The exit end of the electric field anode 4051 and the near exit end of the electric field cathode 4052 have an angle α, and α=118°, and then the electric field anode 4051 and the electric field Under the action of the cathode 4052, more materials to be processed can be collected, ensuring higher dust collection efficiency of the electric field generating unit. The typical tail gas particle pm0.23 dust collection efficiency is 99.99%, and the typical 23nm particle removal efficiency is 99.99% .

The exhaust electric field device in this embodiment includes electric field stages composed of a plurality of the above-mentioned electric field generating units, and there are multiple electric field stages so as to effectively improve the dust collection efficiency of the exhaust electric field device by using multiple dust collecting units. In the same electric field level, each electric field anode has the same polarity, and each electric field cathode has the same polarity.

Example 7

In this embodiment, the electric field generating unit is applied to the exhaust electric field device, as shown in FIG. 4, including an electric field anode 4051 and an electric field cathode 4052 for generating an electric field. The electric field anode 4051 and the electric field cathode 4052 are respectively connected to the two electrodes of the power supply. The power supply is a DC power supply, and the electric field anode 4051 and the electric field cathode 4052 are electrically connected to the anode and the cathode of the DC power supply, respectively. In this embodiment, the electric field anode 4051 has a positive electric potential, and the electric field cathode 4052 has a negative electric potential.

In this embodiment, the electric field anode 4051 has a hollow regular hexagonal tube shape, the electric field cathode 4052 has a rod shape, and the electric field cathode 4052 penetrates the electric field anode 4051. The ratio of the dust collection area of the electric field anode 4051 to the discharge area of the electric field cathode 4052 is 1680. :1. The distance between the electric field anode 4051 and the electric field cathode 4052 is 139.9 mm, the electric field anode 4051 has a length of 180 mm, and the electric field cathode 4052 has a length of 180 mm. The electric field anode 4051 includes an exhaust fluid channel, and the exhaust fluid channel includes an inlet. The electric field cathode 4052 is placed in the exhaust fluid channel, the electric field cathode 4052 extends in the direction of the electric field anode exhaust fluid channel, and the inlet end of the electric field anode 4051 is flush with the near inlet end of the electric field cathode 4052 , The outlet end of the electric field anode 4051 is flush with the near outlet end of the electric field cathode 4052, and then under the action of the electric field anode 4051 and the electric field cathode 4052, more materials to be processed can be collected to ensure the dust collection efficiency of the electric field device Even higher, the typical tail gas particle pm0.23 dust collection efficiency is 99.99%, and the typical 23nm particle removal efficiency is 99.99%.

Example 8

In this embodiment, the electric field anode 4051 has a hollow regular hexagonal tube shape, the electric field cathode 4052 has a rod shape, and the electric field cathode 4052 penetrates the electric field anode 4051. The ratio of the dust collection area of the electric field anode 4051 to the discharge area of the electric field cathode 4052 is 1.667 :1. The distance between the electric field anode 4051 and the electric field cathode 4052 is 2.4 mm. The electric field anode 4051 has a length of 30 mm, and the electric field cathode 4052 has a length of 30 mm. The electric field anode 4051 includes an exhaust fluid channel. The exhaust fluid channel includes an inlet end and an outlet end. The electric field cathode 4052 is placed in the exhaust fluid channel. The electric field cathode 4052 extends along the direction of the electric field anode tail gas fluid channel, the inlet end of the electric field anode 4051 is flush with the proximal inlet end of the electric field cathode 4052, and the outlet end of the electric field anode 4051 is flush with the proximal outlet end of the electric field cathode 4052, and then Under the action of electric field anode 4051 and electric field cathode 4052, more materials to be processed can be collected, ensuring higher dust collection efficiency of the electric field device. The dust collection efficiency of typical tail gas particles pm0.23 is 99.99%, and typical 23nm particles The removal efficiency is 99.99%.

In this embodiment, the electric field anode 4051 and the electric field cathode 4052 constitute a dust collection unit, and there are multiple dust collection units, so that the use of multiple dust collection units can effectively improve the dust collection efficiency of the exhaust electric field device.

In this embodiment, the above-mentioned substance to be treated may be particulate dust. In this embodiment, the above-mentioned gas is the product of the ultraviolet device processing VOCs in the exhaust gas of the engine.

Example 9

The VOCs gas treatment system in the engine exhaust in this embodiment includes the exhaust electric field device in the above-mentioned embodiment 6, embodiment 7 or embodiment 8. The exhaust gas discharged from the engine must first flow through the ultraviolet device, and the product after the ultraviolet device treats VOCs and then flows through the exhaust gas electric field device, so that the exhaust gas electric field device can effectively remove the dust and other pollutants in the gas; The latter gas is then discharged to the atmosphere to reduce the impact of engine exhaust on the atmosphere.

Example 10

In this embodiment, the electric field generating unit is applied to an exhaust electric field device, as shown in FIG. 4, including an electric field anode 4051 and an electric field cathode 4052 for forming an exhaust ionization and dust removal electric field. Each electrode is electrically connected, the power source is a DC power source, and the electric field anode 4051 and the electric field cathode 4052 are electrically connected to the anode and cathode of the DC power source, respectively. In this embodiment, the electric field anode 4051 has a positive electric potential, and the electric field cathode 4052 has a negative electric potential.

In this embodiment, the electric field anode 4051 is in the shape of a hollow regular hexagon, the electric field cathode 4052 is in the shape of a rod, and the electric field cathode 4052 is inserted in the electric field anode 4051. The electric field anode 4051 has a length of 5 cm and the electric field cathode 4052 has a length of 5 cm. 4051 includes an exhaust fluid channel, the exhaust fluid channel includes an inlet end and an outlet end, the electric field cathode 4052 is placed in the exhaust fluid channel, the electric field cathode 4052 extends in the direction of the electric field anode exhaust fluid channel, and the electric field anode 4051 The inlet end of the electric field is flush with the near inlet end of the electric field cathode 4052, and the outlet end of the electric field anode 4051 is flush with the near outlet end of the electric field cathode 4052. The distance between the electric field anode 4051 and the electric field cathode 4052 is 9.9 mm. Under the action of the anode 4051 and the electric field cathode 4052, it can withstand high-temperature shocks, and can collect more materials to be processed, ensuring that the dust collection efficiency of the electric field generating unit is higher. An electric field temperature of 200°C corresponds to a dust collection efficiency of 99.9%; an electric field temperature of 400°C corresponds to a dust collection efficiency of 90%; an electric field temperature of 500°C corresponds to a dust collection efficiency of 50%.

The exhaust electric field device in this embodiment includes an electric field stage composed of a plurality of the above-mentioned electric field generating units, and there are multiple electric field stages to effectively improve the dust collection efficiency of the electric field device by using a plurality of dust collecting units. In the same electric field level, each electric field anode has the same polarity, and each electric field cathode has the same polarity.

Example 11

In this embodiment, the electric field generating unit is applied to the exhaust electric field device, as shown in FIG. 4, including an electric field anode 4051 and an electric field cathode 4052 for generating an electric field. The power supply is a DC power supply, and the electric field anode 4051 and the electric field cathode 4052 are electrically connected to the anode and the cathode of the DC power supply, respectively. In this embodiment, the electric field anode 4051 has a positive electric potential, and the electric field cathode 4052 has a negative electric potential.

In this embodiment, the electric field anode 4051 is in the shape of a hollow regular hexagon, the electric field cathode 4052 is in the shape of a rod, and the electric field cathode 4052 is inserted in the electric field anode 4051. The electric field anode 4051 has a length of 9 cm, and the electric field cathode 4052 has a length of 9 cm. 4051 includes an exhaust fluid channel, the exhaust fluid channel includes an inlet end and an outlet end, the electric field cathode 4052 is placed in the exhaust fluid channel, the electric field cathode 4052 extends in the direction of the electric field anode exhaust fluid channel, and the electric field anode 4051 The inlet end of the electric field cathode 4052 is flush with the near inlet end of the electric field cathode 4052, and the outlet end of the electric field anode 4051 is flush with the near outlet end of the electric field cathode 4052. The distance between the electric field anode 4051 and the electric field cathode 4052 is 139.9 mm. Under the action of the anode 4051 and the electric field cathode 4052, it can withstand high-temperature shocks, and can collect more materials to be processed, ensuring that the dust collection efficiency of the electric field generating unit is higher. An electric field temperature of 200°C corresponds to a dust collection efficiency of 99.9%; an electric field temperature of 400°C corresponds to a dust collection efficiency of 90%; an electric field temperature of 500°C corresponds to a dust collection efficiency of 50%.

The exhaust electric field device in this embodiment includes an electric field stage composed of a plurality of the above-mentioned electric field generating units, and there are multiple electric field stages to effectively improve the dust collection efficiency of the electric field device by using a plurality of dust collecting units. In the same electric field level, each storage electric field anode has the same polarity, and each electric field cathode has the same polarity.

Example 12

In this embodiment, the electric field anode 4051 is in the shape of a hollow regular hexagon, the electric field cathode 4052 is in the shape of a rod, and the electric field cathode 4052 is inserted in the electric field anode 4051. The electric field anode 4051 has a length of 1 cm and the electric field cathode 4052 has a length of 1 cm. 4051 includes an exhaust fluid channel, the exhaust fluid channel includes an inlet end and an outlet end, the electric field cathode 4052 is placed in the exhaust fluid channel, the electric field cathode 4052 extends in the direction of the electric field anode exhaust fluid channel, and the electric field anode 4051 The inlet end of the electric field cathode 4052 is flush with the near inlet end of the electric field cathode 4052, and the outlet end of the electric field anode 4051 is flush with the near outlet end of the electric field cathode 4052. The distance between the electric field anode 4051 and the electric field cathode 4052 is 2.4 mm. Under the action of the anode 4051 and the electric field cathode 4052, it can withstand high-temperature shocks, and can collect more materials to be processed, ensuring that the dust collection efficiency of the electric field generating unit is higher. An electric field temperature of 200°C corresponds to a dust collection efficiency of 99.9%; an electric field temperature of 400°C corresponds to a dust collection efficiency of 90%; an electric field temperature of 500°C corresponds to a dust collection efficiency of 50%.

The electric field stages of the plurality of electric field stages are connected in series, and the series electric field stages are connected by a connecting shell. The distance between the electric field stages of two adjacent stages is greater than 1.4 times of the pole spacing. The electric field has two levels, namely a first electric field and a second electric field, and the first electric field and the second electric field are connected in series through the connecting shell.

Example 13

As shown in Figures 4 and 5, the electric field anode 4051 in this embodiment is a hollow regular hexagonal tube, the electric field cathode 4052 is rod-shaped, and the electric field cathode 4052 penetrates the electric field anode 4051. The electric field anode 4051 has a length of 3 cm. 4052 is 2cm in length. The electric field anode 4051 includes an exhaust fluid channel, the exhaust fluid channel includes an inlet end and an outlet end, the electric field cathode 4052 is placed in the exhaust fluid channel, and the electric field cathode 4052 runs along the electric field anode exhaust The direction of the fluid channel extends, the inlet end of the electric field anode 4051 is flush with the near inlet end of the electric field cathode 4052, the outlet end of the electric field anode 4051 and the near outlet end of the electric field cathode 4052 have an angle α, and α=90°, The distance between the electric field anode 4051 and the electric field cathode 4052 is 20 mm, and under the action of the electric field anode 4051 and the electric field cathode 4052, it can withstand high temperature impact, and can collect more materials to be processed to ensure the occurrence of the electric field The dust collection efficiency of the unit is higher. An electric field temperature of 200°C corresponds to a dust collection efficiency of 99.9%; an electric field temperature of 400°C corresponds to a dust collection efficiency of 90%; an electric field temperature of 500°C corresponds to a dust collection efficiency of 50%.

The exhaust electric field device in this embodiment includes an electric field stage composed of a plurality of the above-mentioned electric field generating units, and there are multiple electric field stages to effectively improve the dust collection efficiency of the electric field device by using a plurality of dust collecting units. In the same electric field level, each dust collection is extremely the same polarity, and each discharge is extremely the same polarity.

The electric field stages of the plurality of electric field stages are connected in series, and the series electric field stages are connected by a connecting shell. The distance between the electric field stages of two adjacent stages is greater than 1.4 times of the pole spacing. As shown in Fig. 7, the electric field has two levels, namely, the first electric field and the second electric field, and the first electric field and the second electric field are connected in series through the connecting shell.

Example 14

The VOCs gas treatment system in the engine exhaust in this embodiment includes the exhaust electric field device in the above-mentioned embodiment 10, embodiment 11, embodiment 12 or embodiment 13. The exhaust gas discharged from the engine must first flow through the ultraviolet device, and the product after the ultraviolet device treats the VOCs and then flows through the exhaust electric field device, so that the exhaust electric field device can effectively remove the dust and other pollutants in the exhaust gas; The latter gas is then discharged to the atmosphere to reduce the impact of engine exhaust on the atmosphere.

Example 15

In this embodiment, the electric field anode 4051 is in the shape of a hollow regular hexagon, the electric field cathode 4052 is in the shape of a rod, and the electric field cathode 4052 is inserted in the electric field anode 4051. The ratio of the dust collection area of the electric field anode 4051 to the discharge area of the electric field cathode 4052 is 27.566 :1, the distance between the electric field anode 4051 and the electric field cathode 4052 is 2.3 mm. The electric field anode 4051 has a length of 5 mm, and the electric field cathode 4052 has a length of 4 mm. The electric field anode 4051 includes an exhaust fluid channel. The exhaust fluid channel includes an inlet end and an outlet end. The electric field cathode 4052 is placed in the exhaust fluid channel. The electric field cathode 4052 extends along the direction of the electric field anode exhaust fluid channel, the inlet end of the electric field anode 4051 is flush with the proximal inlet end of the electric field cathode 4052, and the outlet end of the electric field anode 4051 is flush with the proximal outlet end of the electric field cathode 4052. Under the action of the electric field anode 4051 and the electric field cathode 4052, more materials to be processed can be collected, and the dust collection efficiency of the electric field device can be guaranteed higher.

Example 16

In this embodiment, the electric field anode 4051 has a hollow regular hexagonal tube shape, the electric field cathode 4052 has a rod shape, and the electric field cathode 4052 penetrates the electric field anode 4051. The ratio of the dust collection area of the electric field anode 4051 to the discharge area of the electric field cathode 4052 is 1.108 :1, the distance between the electric field anode 4051 and the electric field cathode 4052 is 2.3 mm. The electric field anode 4051 has a length of 60 mm, and the electric field cathode 4052 has a length of 200 mm. The electric field anode 4051 includes an exhaust fluid channel. The exhaust fluid channel includes an inlet end and an outlet end. The electric field cathode 4052 is placed in the exhaust fluid channel. The electric field cathode 4052 extends along the direction of the electric field anode tail gas fluid channel, the inlet end of the electric field anode 4051 is flush with the proximal inlet end of the electric field cathode 4052, and the outlet end of the electric field anode 4051 is flush with the proximal outlet end of the electric field cathode 4052, and then Under the action of the electric field anode 4051 and the electric field cathode 4052, more materials to be processed can be collected, ensuring higher dust collection efficiency of the electric field device

Example 17

In this embodiment, the electric field anode 4051 is in the shape of a hollow regular hexagon, the electric field cathode 4052 is in the shape of a rod, and the electric field cathode 4052 is inserted in the electric field anode 4051. The ratio of the dust collection area of the electric field anode 4051 to the discharge area of the electric field cathode 4052 is 3065. :1. The distance between the electric field anode 4051 and the electric field cathode 4052 is 249 mm. The electric field anode 4051 has a length of 2000 mm, and the electric field cathode 4052 has a length of 180 mm. The electric field anode 4051 includes an exhaust fluid channel. The exhaust fluid channel includes an inlet end and an outlet end. The electric field cathode 4052 is placed in the exhaust fluid channel. The electric field cathode 4052 extends along the direction of the electric field anode tail gas fluid channel, the inlet end of the electric field anode 4051 is flush with the proximal inlet end of the electric field cathode 4052, and the outlet end of the electric field anode 4051 is flush with the proximal outlet end of the electric field cathode 4052, and then Under the action of the electric field anode 4051 and the electric field cathode 4052, more materials to be processed can be collected, ensuring higher dust collection efficiency of the electric field device

Example 18

In this embodiment, the electric field anode 4051 has a hollow regular hexagonal tube shape, the electric field cathode 4052 has a rod shape, and the electric field cathode 4052 penetrates the electric field anode 4051. The ratio of the dust collection area of the electric field anode 4051 to the discharge area of the electric field cathode 4052 is 1.338 :1, the distance between the electric field anode 4051 and the electric field cathode 4052 is 5 mm. The electric field anode 4051 has a length of 2 mm, and the electric field cathode 4052 has a length of 10 mm. The electric field anode 4051 includes an exhaust fluid channel. The exhaust fluid channel includes an inlet end and an outlet end. The electric field cathode 4052 is placed in the exhaust fluid channel. The electric field cathode 4052 extends along the direction of the electric field anode tail gas fluid channel, the inlet end of the electric field anode 4051 is flush with the proximal inlet end of the electric field cathode 4052, and the outlet end of the electric field anode 4051 is flush with the proximal outlet end of the electric field cathode 4052, and then Under the action of the electric field anode 4051 and the electric field cathode 4052, more materials to be processed can be collected, ensuring higher dust collection efficiency of the electric field device

Example 19

In this embodiment, the electric field device is applied to the VOCs gas treatment system in engine exhaust, and includes a dust removal electric field cathode 5081 and a dust removal electric field anode 5082 electrically connected to the cathode and anode of the DC power supply, respectively, and the auxiliary electrode 5083 is electrically connected to the anode of the DC power supply. In this embodiment, the dust removal electric field cathode 5081 has a negative electric potential, and the dust removal electric field anode 5082 and the auxiliary electrode 5083 both have a positive electric potential.

At the same time, as shown in FIG. 8, the auxiliary electrode 5083 and the dust removal electric field anode 5082 are fixedly connected in this embodiment. After the dust removal electric field anode 5082 is electrically connected to the anode of the DC power supply, the auxiliary electrode 5083 is also electrically connected to the anode of the DC power supply, and the auxiliary electrode 5083 and the dust removal electric field anode 5082 have the same positive potential.

As shown in FIG. 8, the auxiliary electrode 5083 in this embodiment can extend in the front-to-back direction, that is, the length direction of the auxiliary electrode 5083 can be the same as the length direction of the dust removal electric field anode 5082.

As shown in FIG. 8, in this embodiment, the dust removal electric field anode 5082 is tubular, the dust removal electric field cathode 5081 is rod-shaped, and the dust removal electric field cathode 5081 is inserted in the dust removal electric field anode 5082. At the same time, the auxiliary electrode 5083 in this embodiment is also tubular, and the auxiliary electrode 5083 and the dust removal electric field anode 5082 constitute an anode tube 5084. The front end of the anode tube 5084 is flush with the cathode 5081 of the dust removal electric field, and the rear end of the anode tube 5084 extends backwards beyond the rear end of the cathode 5081 of the dust removal electric field. Electrode 5083. That is, in this embodiment, the length of the dedusting electric field anode 5082 and the dedusting electric field cathode 5081 are the same, and the dedusting electric field anode 5082 and the dedusting electric field cathode 5081 are opposite in the front and rear direction; the auxiliary electrode 5083 is located behind the dedusting electric field anode 5082 and the dedusting electric field cathode 5081. In this way, an auxiliary electric field is formed between the auxiliary electrode 5083 and the dust removal electric field cathode 5081. The auxiliary electric field applies a backward force to the negatively charged oxygen ion flow between the dust removal electric field anode 5082 and the dust removal electric field cathode 5081, so that the dust removal electric field anode 5082 and The negatively charged oxygen ion flow between the cathode 5081 of the dust removal electric field has a backward moving speed. When the gas containing the substance to be treated flows into the anode tube 5084 from front to back, the negatively charged oxygen ions will be combined with the substance to be treated in the process of moving backwards towards the anode 5082 of the dust removal electric field. Because the oxygen ions have a backward movement Speed, when the oxygen ions are combined with the substance to be treated, there will be no strong collision between the two, so as to avoid large energy consumption due to the strong collision, making the oxygen ions easy to combine with the substance to be treated, and The charging efficiency of the substances to be treated in the gas is higher, and more substances to be treated can be collected under the action of the dust removal electric field anode 5082 and the anode tube 5084, and the dust removal efficiency of the electric field device is guaranteed.

In addition, as shown in FIG. 8, in this embodiment, there is an angle α between the rear end of the anode tube 5084 and the rear end of the dust removal

electric field cathode

5081, and 0°<α≤125°, or 45°≤α≤125° , Or 60°≤α≤100°, or α=90°.

In this embodiment, the dust removal electric field anode 5082, the auxiliary electrode 5083, and the dust removal electric field cathode 5081 constitute a dust removal unit, and there are multiple dust removal units to effectively improve the dust removal efficiency of the electric field device by using multiple dust removal units.

In this embodiment, the above-mentioned substance to be treated may be granular dust or other impurities that need to be treated.

In this embodiment, the above-mentioned gas may be a product after the ultraviolet device treats VOCs in engine exhaust.

The DC power supply in this embodiment may specifically be a DC high-voltage power supply. A tail gas ionization and dust removal electric field is formed between the foregoing dust removal electric field cathode 5081 and the dust removal electric field anode 5082, and the tail gas ionization dust removal electric field is an electrostatic field. Without the auxiliary electrode 5083, the ion current in the electric field between the dust removal electric field cathode 5081 and the dust removal electric field anode 5082 runs in the direction perpendicular to the electrode, and flows back and forth between the two electrodes, causing the ions to be folded back and forth between the electrodes for consumption. For this reason, in this embodiment, the auxiliary electrode 5083 is used to stagger the relative positions of the electrodes to form a relative imbalance between the dust removal electric field anode 5082 and the dust removal electric field cathode 5081. This imbalance will deflect the ion current in the electric field. In this electric field device, an auxiliary electrode 5083 is used to form an electric field capable of directional ion flow. In this embodiment, the electric field device described above is also referred to as an electric field device with an acceleration direction. The collection rate of the electric field device for particles entering the electric field in the direction of ion flow is nearly double that of particles entering the electric field in the direction of counter ion flow, thereby improving the efficiency of electric field dust accumulation and reducing electric field power consumption. In addition, the main reason for the low dust removal efficiency of the dust collecting electric field in the prior art is that the direction of the dust entering the electric field is opposite or perpendicular to the direction of the ion flow in the electric field, which causes the dust and the ion flow to collide violently with each other and produce large energy consumption. It also affects the charging efficiency, thereby reducing the electric field dust collection efficiency in the prior art and increasing the energy consumption.

When the electric field device in this embodiment is used to collect dust in the gas, the gas and dust enter the electric field along the direction of ion flow, the dust is fully charged, and the electric field consumption is small; the dust collection efficiency of the unipolar electric field can reach 99.99%. When the gas and dust enter the electric field against the direction of ion flow, the dust is not fully charged, the electric power consumption of the electric field will increase, and the dust collection efficiency will be 40%-75%. In addition, the ion flow formed by the electric field device in this embodiment is beneficial to the unpowered fan fluid transportation, oxygenation, heat exchange, etc.

Example 20

The electric field device in this embodiment is applied to the VOCs gas treatment system in engine exhaust gas, and includes a dust removal electric field cathode and a dust removal electric field anode respectively electrically connected to the cathode and anode of the DC power supply, and the auxiliary electrode is electrically connected to the cathode of the DC power supply. In this embodiment, the auxiliary electrode and the cathode of the dust removal electric field both have a negative electric potential, and the anode of the dust removal electric field has a positive electric potential.

In this embodiment, the auxiliary electrode can be fixedly connected to the cathode of the dust removal electric field. In this way, after the electrical connection between the cathode of the dust removal electric field and the cathode of the DC power supply is realized, the electrical connection between the auxiliary electrode and the cathode of the DC power supply is also realized. At the same time, the auxiliary electrode in this embodiment extends in the front-rear direction.

In this embodiment, the anode of the dust removal electric field is tubular, the cathode of the dust removal electric field is rod-shaped, and the cathode of the dust removal electric field penetrates the anode of the dust removal electric field. At the same time, the above-mentioned auxiliary electrode in this embodiment is also rod-shaped, and the auxiliary electrode and the dust-removing electric field cathode constitute a cathode rod. The front end of the cathode rod forwards beyond the front end of the anode of the dust removal electric field, and the part of the cathode rod that exceeds the anode of the dust removal electric field forward is the auxiliary electrode. That is, in this embodiment, the length of the dust removal electric field anode and the dust removal electric field cathode are the same, and the dust removal electric field anode and the dust removal electric field cathode are opposite in the front and rear direction; the auxiliary electrode is located in front of the dust removal electric field anode and the dust removal electric field cathode. In this way, an auxiliary electric field is formed between the auxiliary electrode and the anode of the dust removal electric field. The auxiliary electric field exerts a backward force on the negatively charged oxygen ion flow between the anode of the dust removal electric field and the cathode of the dust removal electric field, so that there is a gap between the anode of the dust removal electric field and the cathode of the dust removal electric field. The stream of negatively charged oxygen ions has a backward moving speed. When the gas containing the substance to be treated flows into the tubular dust removal electric field anode from front to back, the negatively charged oxygen ions will be combined with the substance to be treated in the process of moving to the dust removal electric field anode and back, because oxygen ions have a backward The moving speed, when the oxygen ions are combined with the substance to be treated, there will be no strong collision between the two, so as to avoid the large energy consumption caused by the strong collision, making the oxygen ions easy to combine with the substance to be treated. And it makes the charging efficiency of the substances to be treated in the gas higher, and furthermore, under the action of the anode of the dust removal electric field, more substances to be treated can be collected, and the dust removal efficiency of the electric field device is guaranteed.

In this embodiment, the dust removal electric field anode, the auxiliary electrode, and the dust removal electric field cathode constitute a dust removal unit, and there are multiple dust removal units to effectively improve the dust removal efficiency of the electric field device by using multiple dust removal units.

Example 21

As shown in FIG. 9, the electric field device in this embodiment is applied to the VOCs gas treatment system in engine exhaust, and the auxiliary electrode 5083 extends in the left and right directions. In this embodiment, the length direction of the auxiliary electrode 5083 is different from the length directions of the dust removal electric field anode 5082 and the dust removal electric field cathode 5081. In addition, the auxiliary electrode 5083 may be perpendicular to the anode 5082 of the dust removal electric field.

In this embodiment, the dust removal electric field cathode 5081 and the dust removal electric field anode 5082 are electrically connected to the cathode and anode of the DC power supply, respectively, and the auxiliary electrode 5083 is electrically connected to the anode of the DC power supply. In this embodiment, the dust removal electric field cathode 5081 has a negative electric potential, and the dust removal electric field anode 5082 and the auxiliary electrode 5083 both have a positive electric potential.

As shown in FIG. 9, in this embodiment, the dust removal electric field cathode 5081 and the dust removal electric field anode 5082 are opposed to each other in the front and rear direction, and the auxiliary electrode 5083 is located behind the dust removal electric field anode 5082 and the dust removal electric field cathode 5081. In this way, an auxiliary electric field is formed between the auxiliary electrode 5083 and the dust removal electric field cathode 5081. The auxiliary electric field applies a backward force to the negatively charged oxygen ion flow between the dust removal electric field anode 5082 and the dust removal electric field cathode 5081, so that the dust removal electric field anode 5082 and The negatively charged oxygen ion flow between the cathode 5081 of the dust removal electric field has a backward moving speed. When the gas containing the substance to be treated flows from front to back into the electric field between the dust removal electric field anode 5082 and the dust removal electric field cathode 5081, the negatively charged oxygen ions will interact with the material to be treated in the process of moving to the dust removal electric field anode 5082 and backward. Combination, because oxygen ions have a backward moving speed, when the oxygen ions are combined with the material to be treated, there will be no strong collision between the two, so as to avoid greater energy consumption due to strong collisions and make oxygen The ions are easy to combine with the substances to be treated, and make the charging efficiency of the substances to be treated in the gas higher. Then, under the action of the dust removal electric field anode 5082, more substances to be treated can be collected to ensure the dust removal of the electric field device higher efficiency.

Example 22

As shown in FIG. 10, the electric field device in this embodiment is applied to the VOCs gas treatment system in engine exhaust, and the auxiliary electrode 5083 extends in the left and right directions. In this embodiment, the length direction of the auxiliary electrode 5083 is different from the length directions of the dust removal electric field anode 5082 and the dust removal electric field cathode 5081. In addition, the auxiliary electrode 5083 may be perpendicular to the cathode 5081 of the dust removal electric field.

In this embodiment, the dust removal electric field cathode 5081 and the dust removal electric field anode 5082 are electrically connected to the cathode and anode of the DC power supply, respectively, and the auxiliary electrode 5083 is electrically connected to the cathode of the DC power supply. In this embodiment, the dust removal electric field cathode 5081 and the auxiliary electrode 5083 both have a negative electric potential, and the dust removal electric field anode 5082 has a positive electric potential.

As shown in FIG. 10, in this embodiment, the dust removal electric field cathode 5081 and the dust removal electric field anode 5082 are positioned opposite to each other in the front and rear direction, and the auxiliary electrode 5083 is located in front of the dust removal electric field anode 5082 and the dust removal electric field cathode 5081. In this way, an auxiliary electric field is formed between the auxiliary electrode 5083 and the dedusting electric field anode 5082. The auxiliary electric field applies a backward force to the negatively charged oxygen ion flow between the dedusting electric field anode 5082 and the dedusting electric field cathode 5081, so that the dedusting electric field anode 5082 and The negatively charged oxygen ion flow between the cathode 5081 of the dust removal electric field has a backward moving speed. When the gas containing the substance to be treated flows from front to back into the electric field between the dust removal electric field anode 5082 and the dust removal electric field cathode 5081, the negatively charged oxygen ions will interact with the material to be treated in the process of moving to the dust removal electric field anode 5082 and backward. Combination, because oxygen ions have a backward moving speed, when the oxygen ions are combined with the material to be treated, there will be no strong collision between the two, so as to avoid greater energy consumption due to strong collisions and make oxygen The ions are easy to combine with the substances to be treated, and make the charging efficiency of the substances to be treated in the gas higher. Then, under the action of the dust removal electric field anode 5082, more substances to be treated can be collected to ensure the dust removal of the electric field device higher efficiency.

Example 23

The VOCs gas treatment system in the engine exhaust in this embodiment includes the electric field device in the above embodiment 19, 20, 21 or 22. The exhaust gas discharged from the engine needs to flow through the ultraviolet device first, and the product after the ultraviolet device treats the exhaust gas then flows through the electric field device to effectively remove the dust and other pollutants in the gas by the electric field device; then, the treated product The gas is then discharged to the atmosphere to reduce the impact of engine exhaust on the atmosphere. In this embodiment, the engine exhaust device is also called an exhaust gas treatment device, the dust removal electric field cathode 5081 is also called an electric field cathode, and the dust removal electric field anode 5082 is also called an electric field anode.

Example 24

In this embodiment, the engine exhaust dust removal system includes an exhaust gas cooling device for reducing the exhaust gas temperature before the entrance of the electric field device. In this embodiment, the exhaust gas cooling device can be connected to the inlet of the electric field device.

As shown in FIG. 11, this embodiment provides an exhaust gas cooling device, including:

The heat exchange unit 3071 is used for heat exchange with the exhaust gas of the engine, so as to heat the liquid heat exchange medium in the heat exchange unit 3071 into a gaseous heat exchange medium.

The heat exchange unit 3071 in this embodiment may include:

The exhaust gas passage cavity is connected to the exhaust pipe of the engine, and the exhaust gas passage cavity is used for the exhaust gas of the engine to pass through;

The medium gasification chamber is used to convert the liquid heat exchange medium and the exhaust gas into a gaseous heat exchange medium after heat exchange.

In this embodiment, there is a liquid heat exchange medium in the medium vaporization cavity, and the liquid heat exchange medium is converted into a gaseous heat exchange medium after heat exchange with the tail gas in the tail gas passing through the cavity. The exhaust gas passes through the cavity to realize the collection of automobile exhaust gas. In this embodiment, the length directions of the medium vaporization cavity and the tail gas passage cavity may be the same, that is, the axis of the medium vaporization cavity and the axis of the tail gas passage cavity coincide. In this embodiment, the medium vaporization chamber may be located in the exhaust gas passage cavity or outside the exhaust gas passage cavity. In this way, when the vehicle exhaust flows through the exhaust gas passage cavity, the heat carried by the vehicle exhaust gas will be transferred to the liquid in the vaporization cavity of the medium, and the liquid will be heated above the boiling point. The liquid will vaporize into a gaseous medium such as high temperature and high pressure vapor. Flow in the medium gasification chamber. In this embodiment, the medium gasification cavity may be fully covered or the part except the front end thereof may be covered inside and outside the exhaust gas passage cavity.

The exhaust gas cooling device in this embodiment further includes a power generation unit 3072, which is used to convert the thermal energy of the heat exchange medium and/or the exhaust gas into mechanical energy.

The exhaust gas cooling device in this embodiment may further include a power generation unit 3073, which is used to convert the mechanical energy generated by the power generation unit 3072 into electrical energy.

The working principle of the exhaust gas cooling device in this embodiment is: the heat exchange unit 3071 exchanges heat with the exhaust gas of the engine to heat the liquid heat exchange medium in the heat exchange unit 3071 into a gaseous heat exchange medium; the power generation unit 3072 will The thermal energy of the heat exchange medium or the thermal energy of the exhaust gas is converted into mechanical energy; if the power generation unit 3073 is included, the power generation unit 3073 converts the mechanical energy generated by the power generation unit 3072 into electrical energy, thereby realizing the use of engine exhaust gas for power generation, avoiding the heat and pressure carried by the exhaust gas. Waste; and when the heat exchange unit 3071 exchanges heat with the exhaust gas, it can also play the role of heat dissipation and cooling of the exhaust gas, so that other exhaust gas purification devices can be used to treat the exhaust gas and improve the subsequent exhaust gas treatment efficiency .

The heat exchange medium in this embodiment can be water, methanol, ethanol, oil, or alkane. The above-mentioned heat exchange medium is a substance that can change phase due to temperature, and its volume and pressure also change accordingly during the phase change process.

The heat exchange unit 3071 in this embodiment is also called a heat exchanger. In this embodiment, the heat exchange unit 3071 may adopt a tube heat exchange device. The design considerations of the heat exchange unit 3071 include pressure bearing, volume reduction, and heat exchange area increase.

As shown in FIG. 11, the exhaust gas cooling device in this embodiment may further include a medium transmission unit 3074 connected between the heat exchange unit 3071 and the power generation unit 3072. The gaseous medium such as vapor formed in the medium gasification chamber acts on the power generation unit 3072 through the medium transmission unit 3074. The medium transmission unit 3074 includes a pressure-bearing pipeline.

In this embodiment, the power generation unit 3072 includes a turbofan. The turbofan can convert the pressure generated by gaseous media such as steam or tail gas into kinetic energy. And the turbofan includes a turbofan shaft and at least one set of turbofan components fixed on the turbofan shaft. The turbofan assembly includes a guide fan and a power fan. When the steam pressure acts on the turbofan assembly, the turbofan shaft will rotate with the turbofan assembly, thereby converting the steam pressure into kinetic energy. When the power generation unit 3072 includes a turbofan, the pressure of the exhaust gas of the engine can also act on the turbofan to drive the turbofan to rotate. In this way, the steam pressure and the exhaust gas pressure can alternately and seamlessly switch to act on the turbofan. In this embodiment, if a power generation unit is included, when the turbofan rotates in the first direction, the power generation unit 3073 converts kinetic energy into electric energy to realize waste heat power generation; when the generated electric energy in turn drives the turbofan to rotate, and the turbofan rotates in the second direction. When the direction of rotation is turned, the power generation unit 3073 converts electrical energy into exhaust resistance to provide exhaust resistance for the engine. When the exhaust brake device installed on the engine works to produce engine brake high-temperature and high-pressure exhaust, the turbofan will The braking energy is converted into electrical energy to realize engine exhaust braking and braking power generation.

In this embodiment, a constant negative exhaust pressure can be generated through high-speed turbofan exhaust, which reduces the exhaust resistance of the engine and realizes engine assist. And when the power generation unit 3072 includes a turbofan, the power generation unit 3072 also includes a turbofan adjustment module. The turbofan adjustment module uses the peak of the engine exhaust pressure to push the turbofan to generate the moment of inertia, and further delay the generation of negative exhaust gas pressure to promote the engine Inhale, reduce the exhaust resistance of the engine, and increase the engine power.

The exhaust gas cooling device in this embodiment can be applied to a fuel engine, such as a diesel engine or a gasoline engine. The exhaust gas cooling device in this embodiment can also be applied to a gas engine. Specifically, the present exhaust gas cooling device is used on a diesel engine of a vehicle, that is, the above-mentioned exhaust gas passage cavity communicates with the exhaust port of the diesel engine.

As shown in FIG. 11, the exhaust gas cooling device in this embodiment may further include a coupling unit 3075, which is electrically connected between the power generation unit 3072 and the power generation unit 3073, and the power generation unit 3073 communicates with the power generation unit 3075 through the coupling unit 3075. Unit 3072 is coaxially coupled.

The exhaust gas cooling device in this embodiment may further include a heat preservation pipe connected between the exhaust pipe of the engine and the heat exchange unit 3071. Specifically, the two ends of the thermal insulation pipeline are respectively connected with the exhaust port of the engine system and the exhaust gas passage cavity, so that the thermal insulation pipeline is used to maintain the high temperature of the exhaust gas and introduce the exhaust gas into the exhaust gas passage cavity.

The exhaust gas cooling device in this embodiment may further include a fan, which passes air into the exhaust gas and has a cooling effect on the exhaust gas before the entrance of the electric field device. The air introduced can be 50% to 300%, or 100% to 180%, or 120% to 150% of the exhaust gas.

The exhaust gas cooling device in this embodiment can assist the engine system to realize the recovery and reuse of engine exhaust heat, which helps to reduce engine emissions of greenhouse gases, and also helps to reduce emissions of harmful gases from fuel-fueled engines, reduces pollutant emissions, and saves fuel. Engine emissions are more environmentally friendly.

The intake air of the exhaust gas cooling device can be used to purify the air, when the particle content of the exhaust gas processed by the engine exhaust dust removal system of the present invention is less than that of the air.

The exhaust gas cooling device can be applied to the fields of energy saving and emission reduction of diesel, gasoline, and gas engines, and is an innovative technology for improving engine efficiency, fuel saving technology, and improving engine economy. The exhaust gas cooling device can help the automobile save fuel and improve the fuel economy; it can also make the waste heat of the engine be recycled and use energy efficiently.

In summary, the exhaust gas cooling device of the present invention can realize waste heat power generation based on automobile exhaust gas, and has high thermal energy conversion efficiency, and the heat exchange medium can be recycled; it can be applied to the fields of energy saving and emission reduction such as diesel engines, gasoline engines, and gas engines. The waste heat of the engine can be recycled, thereby improving the economy of the engine; a constant negative exhaust pressure is generated through high-speed turbofan extraction, which reduces the exhaust resistance of the engine and improves the efficiency of the engine. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial value.

Example 25 UV photolysis + ionization dust removal

This embodiment provides a method for processing VOCs in engine exhaust, including the following steps:

The tail gas containing VOCs is subjected to UV purification treatment to obtain the product after UV treatment tail gas;

The product after UV treatment tail gas is subjected to electric field dust removal treatment to remove particulate matter in the product after UV treatment tail gas.

In this embodiment, the electric field dust removal treatment method includes: passing dust-containing gas through an ionization dust removal electric field generated by an electric field anode and an electric field cathode to perform dust removal treatment.

In this embodiment, the electric field dust removal treatment method further includes: the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode, the distance between the electric field anode and the electric field cathode, and the The length of the electric field anode and the length of the electric field cathode make the coupling times of the ionization electric field≤3.

In this embodiment, the electric field dust removal processing method further includes a method of providing an auxiliary electric field, including:

An electric field is generated in the flow channel, and the electric field is not perpendicular to the flow channel; there is an angle α between the inlet end of the electric field cathode and the inlet end of the electric field anode, and α=90°.

1 Main test equipment and materials

1) VOCs stock solution (industrial banana water)

15% n-butyl acetate, 15% ethyl acetate, 10-15% n-butanol, 10% ethanol, 5-10% acetone, 20% benzene + 20% xylene;

2) Ultraviolet photolysis device: UV ultraviolet lamp: U-shaped tube, 150W, 185nm+254nm mixed wavelength;

3) Electric field device: the electric field device of embodiment 1 is adopted;

4) VOCs concentration detection instrument, CO ₂ concentration detection instrument, PM2.5 detection instrument, temperature and humidity detection instrument;

5) 2 air blowers: rated air volume 50L/min and 20L/min;

6) 3 rotameters.

7) PN value detection method: PN value: the number of solid particles, using the principle of light scattering, using a laser dust particle counter to detect the solid particles in the VOC gas, the gas flow rate is 2.8L/min, and 5s is a sampling period .

2 The main test process and parameters.

Referring to FIG. 12, the VOCs treatment system in engine exhaust provided by this embodiment includes an ultraviolet device 4 and an electric field device 5 connected in sequence. The ultraviolet device 4 includes an air inlet 41, an air outlet 42, and an ultraviolet lamp 43.

In this embodiment, the electric field device 5 provided in Embodiment 1 is used, and the air outlet 42 of the ultraviolet device 4 is in communication with the electric field device inlet 51 of the electric field device 5.

Refer to Figure 12, the clean space enters the air humidification tank 1, the humidity of the clean air is adjusted in the air humidification tank 1, the VOCs stock solution is stored in the VOCs storage tank 2, and the clean air from the air humidification tank 1 is combined with the VOCs storage tank The VOCs stock solution is mixed in the mixing buffer tank 3 to control the gas flow of clean air and VOCs stock solution, and the gas flow and concentration of the gas containing VOCs (referred to as VOCs gas) after mixing are controlled at 0.95m ³ /h, 320mg/m ³ .

The VOCs gas is transported into the ultraviolet device 4 through the air inlet 41 of the ultraviolet device for UV purification treatment, and the product after UV treatment is obtained. The purified product is transported to the electric field device 5 through the air outlet 42 for electric field dust removal treatment to remove the purified product The particles are finally discharged from the outlet 52 of the electric field device 5.

Detect the VOCs concentration content, CO ₂ concentration content and PM2.5 value in the VOCs gas at the inlet 41 of the ultraviolet device and the outlet 52 of the electric field device of the electric field device 5 respectively; respectively at the inlet 41 of the ultraviolet device and the outlet 42 of the ultraviolet device , The outlet 52 of the electric field device 5 detects the PN value of solid particles of different sizes in the gas, and the specific detection particle size is 23nm, 0.3μm, 0.5μm, 1.0μm, 3.0μm, 5.0μm, 10μm. The main test parameters are shown in Table 1.

Table 1

3 Experimental conditions and experimental results

Referring to Fig. 12, VOCs with an initial flow rate of 0.95 m ³ /h and an initial concentration of 320 mg/m ³ are passed into the ultraviolet device 4 and the electric field device 5 in sequence.

After turning on the power of the ultraviolet lamp in the ultraviolet device (the electric field device is temporarily not turned on), process 0-717s;

Turn on the DC power supply of the electric field device at 717s, and perform the experiment of removing organic solid particles in the product after UV purification under the conditions of 5.13kV and 0.15mA electric field;

Adjust the DC power supply parameters of the electric field device to 7.07kV and 0.79mA at 1017s, and carry out the experiment of removing organic solid particles in the product after UV purification;

In 1317s, the DC power supply parameters of the electric field device were adjusted to 9.10kV and 2.98mA, and the organic solid particles in the product after UV purification were removed.

3.1 VOCs concentration changes

When the power of the ultraviolet lamp in the ultraviolet device is turned on (the electric field device is temporarily not turned on), the VOCs concentration at the outlet of the electric field device and the VOCs removal rate with time are shown in Figure 13, where A shows the VOCs at the outlet of the electric field device Concentration, B shows the removal efficiency of VOCs, the concentration of VOCs within 80s is basically maintained at 320mg/m ³ without changing, the concentration of VOCs drops rapidly after 80s; the concentration of VOCs drops to 201mg/m ³ after 440s , The removal efficiency is as high as 37.1%.

3.2 Changes in CO ₂ concentration of UV purification VOCs products

Figure 14 is the change curve of CO ₂ concentration at the outlet of the electric field device with treatment time. The initial CO ₂ concentration is 903.3 mg/m ^3. It can be seen from Figure 14 that the CO ₂ concentration increases rapidly after the UV lamp is turned on. When the treatment time reaches After 453s, the CO ₂ concentration reached 1126 mg/m ³ , and then the CO ₂ concentration remained relatively stable within the range of 1135 mg/m ³ . It can be seen that the opening of the dust removal electric field has little effect on the amount of CO ₂ produced.

3.3 PM 2.5 data analysis

Figure 15 shows the change curve of PM2.5 at the outlet of the electric field device with processing time. When the ultraviolet lamp and the electric field device are not turned on, the original PM2.5 value in the VOCs gas is 25μg/m ³ ; it can be seen from Figure 15 that when After turning on the ultraviolet device alone, PM2.5 increased rapidly, and the final PM2.5 value remained at about 5966μg/m ³ , that is, PM2.5 increased by about 240 times.

The DC power supply of the electric field device was turned on at 717s, and the experiment of removing organic solid particles under the conditions of 5.13kV and 0.15mA electric field was carried out. The PM 2.5 value dropped to 10μg/m ³ within 60s of turning on the electric field device, and the removal efficiency of PM 2.5 was 99.8%.

Adjust the DC power supply parameters of the electric field device to 7.07kV and 0.79mA at 1017s, and conduct the experiment of removing organic solid particles in the product after UV purification; 1317s adjust the DC power supply parameters of the electric field device to 9.10kV and 2.98mA for removal Experiment on organic solid particles in the product after UV purification; under these two electric field conditions, the PM2.5 value at the outlet of the dust removal zone is 0μg/m ³ , and the PM 2.5 removal efficiency reaches 100%.

3.4 PN data analysis

When the ultraviolet device and the electric field device are not turned on, the PN value content of solid particles of different sizes in the original VOCs gas is detected. The particle number (PN value) distribution of the solid particles of different sizes in the original VOCs gas is shown in Table 2.

When the ultraviolet device is turned on alone (the electric field device is not turned on) and the maximum VOCs purification efficiency is reached, the PN of solid particles of various sizes in the outlet gas of the dust removal zone increases greatly. For the experimental data, see Table 3. It can be seen from Table 3 that the PN value of 23nm, 0.3μm, 0.5μm, 1.0μm, 3.0μm, 5.0μm, 10μm solid particles increased to 2585933682 pieces/m ³ , 122762968 pieces/m ³ , 122596749 pieces/m ³ , 120574982 pieces, respectively /m ³ , 117328622 pieces/m ³ , 112109682 pieces/m ³ , 105862049 pieces/m ³ , among them, the PN value of the two solid particles of 5.0μm and 10μm increased the most significantly, with an increase of about 150,000 times.

Turn on the DC power supply of the electric field device at 717s, and carry out the experiment of removing organic solid particles under the conditions of 5.13kV and 0.15mA electric field. When the electric field is turned on for 60s under this condition, the PN of the gas at the outlet of the dust removal zone drops significantly. Experimental data See Table 4. It can be seen from Table 4 that under the electric field conditions, the removal efficiency of the four sizes of solid particles of 5.0μm and 10μm basically reached 100%. In addition, the removal efficiency of solid particles of 23nm, 0.3μm, 0.5μm, 1.0μm, 3.0μm The removal efficiency is more than 93%.

Adjust the DC power supply parameters of the electric field device to 7.07kV and 0.79mA at 1017s, and carry out the experiment of removing organic solid particles. When the electric field is turned on for 60s under this condition, the experimental data is shown in Table 5; from Table 5, under this electric field condition, The removal efficiency of solid particles of 23nm, 0.3μm, 0.5μm, 1.0μm, 3.0μm, 5.0μm, and 10μm all reach more than 99%.

Perform 1317s to adjust the DC power supply parameters of the electric field device to 9.10kV and 2.98mA, and carry out the experiment of removing organic solid particles. The experimental data is shown in Table 6. Under this electric field condition, 23nm, 0.3μm, 0.5μm, 1.0μm, 3.0μm, 5.0 The removal efficiency of the solid particles of μm and 10 μm is more than 99%.

Table 2 PN data in the original VOC gas

Table 3 PN data of UV at maximum VOC purification efficiency

Table 4 PN data after purification under 5.13kV and 0.15mA electric field conditions

Table 5 PN data after purification under 7.07kV and 0.79mA electric field conditions

Table 6 PN data after purification under 9.10kV and 2.98mA electric field conditions

Example 26 UV photolysis + ionization dust removal

1. Electric field device: the electric field device of Embodiment 15 is used, and the others are the same as Embodiment 25.

2. Experimental conditions and experimental results

VOCs with an initial flow rate of 0.95 m ³ /h and an initial concentration of 320 mg/m ³ are passed into the ultraviolet device 4 and the electric field device 5 in sequence.

2.1 VOCs concentration changes

The change trend of VOCs concentration is the same as in Example 25.

2.2 Changes in CO ₂ concentration of UV-purified VOCs products

The change trend of the CO ₂ concentration of the product from UV purification of VOCs is the same as in Example 25.

2.3 PM 2.5 data analysis

When the ultraviolet device is turned on alone, the change trend of the PM2.5 value in the gas with the treatment time is the same as that in Example 25.

The DC power supply of the electric field device was turned on at 717s, and the experiment of removing organic solid particles under the conditions of 5.13kV and 0.15mA electric field was carried out. Within 60 seconds of turning on the electric field device, the PM 2.5 value dropped to 0.02μg/m ³ , and the removal efficiency of PM 2.5 was 99%. .

2.4 PN data analysis

When the ultraviolet device and the electric field device are not turned on, the PN value content of solid particles of different sizes in the original gas of VOCs is detected as shown in Table 2.

When the ultraviolet device is turned on alone (the electric field device is not turned on) and the maximum VOCs purification efficiency is reached, the PN of solid particles of various sizes in the outlet gas of the dust removal zone increases greatly. The experimental data is shown in Table 3, the same example 25.

Turn on the DC power supply of the electric field device at 717s, and carry out the experiment of removing organic solid particles under the conditions of 5.13kV and 0.15mA electric field. When the electric field is turned on for 60s under this condition, the PN of the gas at the outlet of the dust removal zone drops significantly. For the experimental data, see The data in Table 7 and Table 7 are the average values of 6 samples. It can be seen from Table 7 that the removal efficiency of solid particles with sizes of 23nm, 0.3μm, 0.5μm, 1.0μm, 3.0μm, 5.0μm, and 10μm all reached more than 99%.

Adjust the DC power supply parameters of the electric field device to 7.07kV and 0.79mA at 1017s, and carry out the experiment of removing organic solid particles. When the electric field is turned on for 60s under this condition, the experimental data is shown in Table 8. The data in Table 8 are the average of 6 samplings Value; from Table 8, it can be seen that the removal efficiency of solid particles with sizes of 23nm, 0.3μm, 0.5μm, 1.0μm, 3.0μm, 5.0μm, and 10μm all reached more than 99%.

In 1317s, the DC power supply parameters of the electric field device were adjusted to 9.10kV and 2.98mA, and the experiment of removing organic solid particles was carried out. The experimental data is shown in Table 9. The data in Table 9 are the average values of 6 samples. Under the electric field conditions, the removal efficiency of 23nm, 0.3μm and 0.5μm solid particles reaches more than 99.99%.

Table 7 PN data after purification under 5.13kV and 0.15mA electric field conditions

Table 8 PN data after purification under 7.07kV and 0.79mA electric field conditions

Table 9 PN data after purification under 9.10kV and 2.98mA electric field conditions

Example 27 UV photolysis + ionization dust removal

1. Electric field device: the electric field device of embodiment 16 is adopted, and the others are the same as embodiment 25.

2. Experimental conditions and experimental results

2.1 VOCs concentration changes

The change trend of VOCs concentration is the same as in Example 25.

2.2 Changes in CO ₂ concentration of UV-purified VOCs products

2.3 PM 2.5 data analysis

2.4 PN data analysis

When the ultraviolet device is turned on alone (the electric field device is not turned on) and the maximum VOCs purification efficiency is reached, the PN of solid particles of various sizes in the outlet gas of the dust removal zone increases greatly. For the experimental data, see Table 3.

Turn on the DC power supply of the electric field device at 717s, and carry out the experiment of removing organic solid particles under the conditions of 5.13kV and 0.15mA electric field. When the electric field is turned on for 60s under this condition, the experimental data is shown in Table 10. The data in Table 10 are all sampled 6 times average value. It can be seen from Table 10 that the removal efficiency of solid particles with sizes of 23nm, 0.3μm, 0.5μm, 1.0μm, 3.0μm, 5.0μm, and 10μm all reached more than 99%.

Adjust the DC power supply parameters of the electric field device to 7.07kV and 0.79mA at 1017s, and carry out the experiment of removing organic solid particles. When the electric field is turned on for 60s under this condition, the experimental data is shown in Table 11. The data in Table 11 are the average of 6 samples Value; From Table 11, it can be seen that the removal efficiency of solid particles with sizes of 23nm, 0.3μm, 0.5μm, 1.0μm, 3.0μm, 5.0μm, and 10μm all reached 99.99% or more.

In 1317s, the DC power supply parameters of the electric field device were adjusted to 9.10kV and 2.98mA, and the experiment of removing organic solid particles was carried out. The experimental data is shown in Table 12. The data in Table 12 are the average values of 6 samples. Under this electric field condition, the solid particles of 23nm, 0.3μm and 0.5μm further dropped to 345 particles/m ³ , 8 particles/m ³ and 0 particles/m ³ , and the removal efficiency reached more than 99.999%.

Table 10 PN data after purification under 5.13kV and 0.15mA electric field conditions

Table 11 PN data after purification under 7.07kV and 0.79mA electric field conditions

Table 12 PN data after purification under 9.10kV and 2.98mA electric field conditions

Example 28 UV photolysis + ionization dust removal

1. Electric field device: the electric field device of embodiment 17 is adopted, and the others are the same as embodiment 25.

2. Experimental conditions and experimental results

2.1 VOCs concentration changes

The change trend of VOCs concentration is the same as in Example 25.

2.2 Changes in CO ₂ concentration of UV-purified VOCs products

2.3 PM 2.5 data analysis

2.4 PN data analysis

The DC power supply of the electric field device was turned on at 717s, and the experiment of removing organic solid particles under the electric field conditions of 5.13kV and 0.15mA was carried out. The experimental data is shown in Table 13, and the data in Table 13 are the average values of 6 samples. When the electric field is turned on for 60 seconds under this condition, the PN of the gas at the outlet of the dust removal zone drops significantly. As can be seen from Table 13, the removal efficiency of solid particles in sizes 23nm, 0.3μm, 0.5μm 1.0μm, 3.0μm, 5.0μm, 10μm Both reached more than 99%.

Adjust the DC power supply parameters of the electric field device to 7.07kV and 0.79mA at 1017s, and perform the experiment of removing organic solid particles. The experimental data is shown in Table 14. The data in Table 14 are the average of 6 samples; when the electric field is turned on for 60s under this condition Then, as can be seen from Table 14, the removal efficiency of solid particles with sizes of 23nm, 0.3μm, 0.5μm and 1.0μm, 3.0μm, 5.0μm, and 10μm all reached more than 99%.

In 1317s, the DC power supply parameters of the electric field device were adjusted to 9.10kV and 2.98mA, and the experiment of removing organic solid particles was carried out. The experimental data is shown in Table 15. The data in Table 15 are the average of 6 samples. Under the electric field condition, the removal efficiency of 23nm, 0.3μm and 0.5μm solid particles are all above 99.99%.

Table 13 PN data after purification under 5.13kV and 0.15mA electric field conditions

Table 14 PN data after purification under the conditions of 7.07kV and 0.79mA electric field

Table 15 PN data after purification under 9.10kV and 2.98mA electric field conditions

Example 29 UV photolysis + ionization dust removal

1. Electric field device: the electric field device of embodiment 18 is used, and the others are the same as embodiment 25.

2. Experimental conditions and experimental results

3.1 VOCs concentration changes

The change trend of VOCs concentration is the same as in Example 25.

3.2 Changes in CO ₂ concentration of UV purification VOCs products

3.3 PM 2.5 data analysis

The DC power supply of the electric field device was turned on at 717s, and the experiment of removing organic solid particles under the conditions of 5.13kV and 0.15mA electric field was carried out. Within 60 seconds of turning on the electric field device, the PM 2.5 value dropped to 0.002μg/m ³ , and the removal efficiency of PM 2.5 was 99.9% .

3.4 PN data analysis

Turn on the DC power supply of the electric field device at 717s, and carry out the experiment of removing organic solid particles under the conditions of 5.13kV and 0.15mA electric field. The experimental data is shown in Table 16. The data in Table 16 are the average values of 6 samplings. When the electric field is turned on for 60 seconds under this condition, the PN of the gas at the outlet of the dust removal zone drops significantly. As can be seen from Table 16, the removal efficiency of solid particles in sizes 23nm, 0.3μm, 0.5μm 1.0μm, 3.0μm, 5.0μm, 10μm Both reached more than 99%.

Adjust the DC power supply parameters of the electric field device to 7.07kV and 0.79mA at 1017s, and carry out the experiment of removing organic solid particles. The experimental data is shown in Table 17. The data in Table 17 are the average value of 6 samples; when the electric field is turned on for 60s under this condition Then, as shown in Table 17, the removal efficiency of solid particles with sizes of 23nm, 0.3μm, 0.5μm, 1.0μm, 3.0μm, 5.0μm, and 10μm all reached more than 99%.

In 1317s, the DC power supply parameters of the electric field device were adjusted to 9.10kV and 2.98mA, and the experiment of removing organic solid particles was carried out. The experimental data is shown in Table 18. The data in Table 18 are the average of 6 samplings. Under the electric field conditions, the removal efficiency of 23nm, 0.3μm and 0.5μm solid particles reaches more than 99.99%.

Table 16 PN data after purification under 5.13kV and 0.15mA electric field conditions

Table 17 PN data after purification under 7.07kV and 0.79mA electric field conditions

Table 18 PN data after purification under 9.10kV and 2.98mA electric field conditions

Example 30 UV photolysis + ionization dust removal

1. Electric field device: the electric field device of embodiment 21 is used, and the others are the same as embodiment 25.

2. Experimental conditions and experimental results

2.1 VOCs concentration changes

The change trend of VOCs concentration is the same as in Example 25.

2.2 Changes in CO ₂ concentration of UV-purified VOCs products

2.3 PM 2.5 data analysis

At 717s, the DC power supply of the electric field device was turned on, and the experiment of removing organic solid particles under the conditions of 5.13kV and 0.15mA electric field was carried out. Within 60 seconds of turning on the electric field device, the PM 2.5 value dropped to 0.21μg/m ³ , and the removal efficiency of PM 2.5 was 99%. .

Adjust the DC power supply parameters of the electric field device to 7.07kV and 0.79mA at 1017s, and conduct the experiment of removing organic solid particles in the product after UV purification; 1317s adjust the DC power supply parameters of the electric field device to 9.10kV and 2.98mA for removal Experiment on organic solid particles in the product after UV purification; under these two electric field conditions, the PM2.5 value at the outlet of the dust removal zone is 0.017μg/m ³ , and the PM 2.5 removal efficiency reaches 99.9%.

2.4 PN data analysis

When the ultraviolet device is turned on alone (the ionization dust removal device is not turned on), and the maximum VOCs purification efficiency is reached, the PN of various sizes of solid particles in the outlet gas of the dust removal zone increases greatly. The experimental data is shown in Table 3.

Turn on the DC power supply of the electric field device at 717s, and carry out the experiment of removing organic solid particles under the electric field conditions of 5.13kV and 0.15mA. The experimental data are shown in Table 19, and the data in Table 19 are the average values of 6 samples. When the electric field is turned on for 60 seconds under this condition, the PN of the gas at the outlet of the dust removal zone drops significantly. As can be seen from Table 19, the removal efficiency of solid particles in sizes 23nm, 0.3μm, 0.5μm 1.0μm, 3.0μm, 5.0μm, 10μm Both reached more than 99%.

At 1017s, adjust the DC power supply parameters of the electric field device to 7.07kV and 0.79mA, and carry out the experiment of removing organic solid particles. The experimental data is shown in Table 20. The data in Table 20 are the average of 6 samples; when the electric field is turned on for 60s under this condition Then, as can be seen from Table 20, the removal efficiency of solid particles with sizes of 23nm, 0.3μm, 0.5μm, 1.0μm, 3.0μm, 5.0μm, and 10μm all reached more than 99.9%.

In 1317s, the DC power supply parameters of the electric field device were adjusted to 9.10kV and 2.98mA, and the experiment of removing organic solid particles was carried out. The experimental data is shown in Table 21. The data in Table 21 are the average values of 6 samples. Under the electric field condition, the removal efficiency of 23nm, 0.3μm and 0.5μm solid particles all reach more than 99.99%.

Table 19 PN data after purification under 5.13kV and 0.15mA electric field conditions

Table 20 PN data after purification under 7.07kV and 0.79mA electric field conditions

Table 21 PN data after purification under 9.10kV and 2.98mA electric field conditions

Example 31 Combination purification of UV + molecular sieve + activated carbon (hereinafter referred to as "combined purification")

This embodiment provides a method for processing VOCs in engine exhaust gas, which includes: subjecting the exhaust gas to UV purification treatment to obtain a product after UV treatment of the exhaust gas; subjecting the product after UV treatment to the exhaust gas for adsorption purification, and then performing electric field dust removal treatment. Refer to FIG. 16 for a schematic flow diagram of the main experimental device of this embodiment.

1 Main test equipment and consumables

a.VOCs stock solution (industrial banana water)

b.UV ultraviolet lamp

U-tube, 150W, 185nm+254nm mixed wavelength

c. Adsorbent

21AE hydrophobic molecular sieve;

Industrial honeycomb activated carbon;

d.VOCs meter, CO ₂ meter, O ₃ meter, PM2.5 meter, temperature and humidity meter

2 Refer to Table 22 for the basic product parameters of adsorbent.

Table 22

3 Test data of combined purification of VOCs

Referring to FIG. 13, the VOCs treatment system in engine exhaust provided by this embodiment includes an ultraviolet device 4 and an adsorption device 6 connected in sequence. The ultraviolet device 4 includes an air inlet 41, an air outlet 42, and an ultraviolet lamp 43. The adsorption device 6 includes an air inlet 61 and an air outlet 62, and the air inlet 61 of the adsorption device 6 is in communication with the air outlet 42 of the ultraviolet device 4.

In this embodiment, the clean space enters the air humidification tank 1, the humidity of the clean air is adjusted in the air humidification tank 1, the VOCs stock solution is stored in the VOCs storage tank 2, and the clean air from the air humidification tank 1 is combined with the VOCs storage tank The VOCs stock solution is mixed in the mixing buffer tank 3, the gas flow of the clean air and the VOCs stock solution is controlled, and the mixed VOCs gas is passed into the ultraviolet device 4 and the adsorption device 6 in sequence. First, a part of it is purified by UV photolysis and photooxidation. The remaining VOCs molecules are removed by physical adsorption purification of molecular sieve with porous structure + activated carbon, and the finally purified gas is discharged through the outlet of the adsorption device to achieve the purpose of VOCs gas purification.

3.1 Experimental data analysis of combined purification with a low VOCs concentration of 614mg/m ³

3.1.1 Fixed parameters

The ultraviolet device 4 is equipped with a 150W U-shaped ultraviolet lamp tube 43, and the adsorption device 6 is filled with 25.1g molecular sieve 63 and 30.8g active 64 respectively. By bubbling clean air, the humidity of the VOCs gas entering the air inlet 41 of the ultraviolet device 4 is controlled above 90% RH. Adjust the gas flow rate of clean air and VOCs stock solution, and control the gas flow rate and concentration of VOCs at 0.9m ³ /h and 614mg/m ³ , see 23 for other experimental parameters.

Table 23

空气温度Air temperature	18℃18℃	空气湿度Air humidity	70％RH70%RH	大气压力Atmospheric pressure	常压Atmospheric
UV灯管波长UV lamp wavelength	185+254nm185+254nm	UV灯管功率UV lamp power	150W150W	净化区停留时间Residence time in purification zone	18.2s18.2s
VOCs原液气体流量VOCs stock liquid gas flow	<0.04m ³/h <0.04m ³ /h	空气气体流量Air gas flow	1.1m ³/h 1.1m ³ /h	缓冲罐出口VOCs流量VOCs flow rate at outlet of buffer tank	0.9m ³/h 0.9m ³ /h
21AE分子筛填装量21AE molecular sieve filling volume	25.1g25.1g	21AE分子筛增重21AE molecular sieve weight gain	2.9g2.9g	光解区入口初始PM2.5Initial PM2.5 at the entrance of the photolysis zone	79μg/m ³ 79μg/m ³
活性炭填装量Activated carbon filling amount	30.8g30.8g	活性炭增重Activated carbon weight gain	0.5g0.5g	吸附区出口最终PM2.5Final PM2.5 at the outlet of the adsorption zone	6096μg/m ³ 6096μg/m ³
缓冲罐气体湿度Buffer tank gas humidity	>90％RH>90%RH	To	To	To	To

3.1.2 VOCs change data at the outlet of each purification unit during the purification process

3.1.2.1 VOCs concentration

Figure 17 is the time-varying curve of VOCs concentration at the air inlet 41, air outlet 42, and outlet 62 of the ultraviolet device 4 when purifying low VOCs concentration, where A shows the VOCs concentration at the outlet of the buffer tank, and B shows ultraviolet The concentration of VOCs at the outlet of the device, C shows the concentration of VOCs at the outlet of the adsorption device. It can be seen from Figure 17 that the change curve of the VOCs concentration at the outlet 62 of the adsorption device 6 shows that at the beginning of the combined purification test, the VOCs concentration at the outlet of the adsorption zone within 0s-600s stabilized at 6-9mg/m3. The combined purification during this period The efficiency reaches 98.5%.

At about 800s (13min), the VOCs concentration at the outlet 62 of the adsorption device 6 = 30mg/m ³ (when the VOCs concentration is set to 5% of the original concentration, the adsorbent penetrates), the adsorbent penetrates, and the combined purification efficiency before penetration At least 95%;

When the combined purification time exceeds the penetration time, the combined purification efficiency gradually decreases. At 7200s (2 hours), the concentration of the outlet 62 of the adsorption device 6 rises to 197mg/m ³ , at this time the concentration of the outlet of the ultraviolet device is 219mg/m ³ , that is The concentration before and after the adsorption purification is basically the same. The molecular sieve + activated carbon combined adsorbent has reached saturation and can no longer play the role of adsorbing and purifying VOCs. The saturated adsorbent needs to be replaced in advance and VOCs desorption regeneration.

The entire combined purification process, from the beginning of the purification to the saturation of the adsorbent in the adsorption device, totals about 7200 seconds. According to the statistics of this test, the VOCs purification efficiency of the UV purification device is basically maintained at about 40.9%.

3.1.2.2 Changes in CO _{2 at the} outlet of each purification unit during the purification process

Figure 18 shows the change curve of CO ₂ concentration at the inlet, outlet and outlet of the UV device with time when purifying low VOCs concentration, where A shows the CO ₂ concentration at the outlet of the buffer tank, and B shows the outlet of the UV device at the CO ₂ concentration, C is the display device of the source outlet concentration of CO ₂ adsorption. It can be seen from Figure 18 that the CO ₂ concentration at the air inlet of the ultraviolet device is maintained at an average level of 852 mg/m ^{3 as} a whole. When the maximum UV VOCs purification efficiency is reached, the CO ₂ concentration at the air outlet of the ultraviolet device is basically maintained at a relatively stable level. 1284mg/m ³ , the new generation rate of CO ₂ after UV purification is stable at about 50.7%.

The CO ₂ concentration at the outlet of the adsorption device reached the maximum value of 1584 mg/m ³ after 360 seconds, and then remained at a relatively stable level of 1472 mg/m ³ , that is, the new CO ₂ generation rate of the combined purification was stabilized at about 72.8%.

UV contrast at the purge outlet means and the adsorption means and a newly generated CO concentration ratio of _2, it is found, the new generation of CO concentration and the adsorption device ₂ is still a substantial increase in, since outlet VOCs from the UV unit, O _3, After H2O enters the adsorption zone, it can be adsorbed on the outer surface of molecular sieve and activated carbon and the inner surface of pores, and the catalytic oxidation and decomposition of VOCs will continue to produce CO2, which can then enter the electric field device for dust removal and further purify the VOCs in the gas.

3.1.2.3 PM 2.5 data comparison between the beginning of combined purification and after the end of combined purification

Before the start of the formal combined purification experiment, the PM2.5 value in the 0.9m ³ /h and 614mg/m ³ VOCs gas was 79 μg/m ^{3. After the} 7200s purification experiment, the PM2.5 value in the outlet gas of the adsorption device rose to 6096μg/m ³ , PM2.5 increased nearly 77 times.

On the one hand, it shows that VOCs not only decompose to generate CO _{2 in the} process of UV photolysis and photooxidation, but also undergo photopolymerization. VOCs molecules polymerize to form organic particles with high molecular weight, which are dispersed in the gas.

3.2 The experimental data analysis of the combined purification of high VOCs concentration of 1105mg/m ³

3.2.1 Experimental fixed parameters

Adjust the gas flow rate of clean air and VOCs stock solution, and control the gas flow rate and concentration of VOCs at 0.9m ³ /h and 1105mg/m ³ , see Table 24 for specific parameters.

Table 24

空气温度Air temperature	19℃19℃	空气湿度Air humidity	70％RH70%RH	大气压力Atmospheric pressure	常压Atmospheric
UV灯管波长UV lamp wavelength	185nm+254nm185nm+254nm	UV灯管功率UV lamp power	150W150W	UV净化区停留时间Residence time in UV purification zone	18.2S18.2S
VOCs原液气体流量VOCs stock liquid gas flow	<0.04m3/h<0.04m3/h	空气气体流量Air gas flow	1.1m3/h1.1m3/h	缓冲罐出口VOCs流量VOCs flow rate at outlet of buffer tank	0.9m ³/h 0.9m ³ /h
21AE分子筛填装量21AE molecular sieve filling volume	23.6g23.6g	21AE分子筛增重21AE molecular sieve weight gain	4.0g4.0g	光解区入口初始PM2.5Initial PM2.5 at the entrance of the photolysis zone	17μg/m ³ 17μg/m ³
活性炭填装量Activated carbon filling amount	30.0g30.0g	活性炭增重Activated carbon weight gain	1.1g1.1g	吸附区出口最终PM2.5Final PM2.5 at the outlet of the adsorption zone	5580μg/m ³ 5580μg/m ³
缓冲罐气体湿度Buffer tank gas humidity	>90％RH>90%RH	To	To	To	To

3.2.2 VOCs change data at the outlet of each purification unit during the purification process

3.2.2.1 VOCs concentration

Figure 19 shows the time-varying curve of VOCs concentration at the inlet, outlet and outlet of the ultraviolet device when purifying high VOCs concentration. A shows the VOCs concentration at the outlet of the buffer tank, and B shows the VOCs at the outlet of the ultraviolet device. Concentration, C shows the VOCs concentration at the outlet of the adsorption device. As can be seen from Figure 19, from the change curve of the VOCs concentration C7 at the outlet of the adsorption zone, it can be seen that at the beginning of the combined purification test, the VOCs concentration at the outlet of the adsorption zone within 0s-600s stabilized at 8-19mg/m ³ , and the combined purification efficiency during this period reached 98.3%.

At about 1020s, the VOCs concentration at the outlet of the adsorption zone = 55mg/m ³ (when the VOCs concentration is set to 5% of the original concentration, the adsorbent penetrates), the adsorbent penetrates, and the combined purification efficiency is at least 94.7% before penetration ；

When the combined purification time exceeds the breakthrough time, the combined purification efficiency gradually decreases. At 7200s (2 hours), the concentration C7 at the outlet of the adsorption zone rises to 451mg/m ³ , at this time the concentration C5 at the outlet of the ultraviolet device is 456mg/m ³ , molecular sieve + activated carbon The combined adsorbent has reached saturation and can no longer play the role of adsorbing and purifying VOCs. At this time, the combined purification efficiency has dropped to 41.1%, and only the UV photolysis device can perform purification.

The entire combined purification process, from the beginning of the purification to the saturation of the adsorbent in the adsorption device, takes about 7200 seconds. According to the statistics of this test, the VOCs purification efficiency of the UV purification device is basically maintained at about 41.1%.

3.2.2.2 Changes in CO _{2 at the} outlet of each purification unit during the purification process

Figure 20 shows the change curve of CO ₂ concentration at the inlet, outlet, and adsorption device outlet of the ultraviolet device with time when purifying high VOCs concentration. A shows the CO ₂ concentration at the outlet of the buffer tank, and B shows the outlet of the ultraviolet device at the CO ₂ concentration, C is the display device of the source outlet concentration of CO ₂ adsorption. It can be seen from Figure 20 that the CO ₂ concentration at the inlet of the UV device remained at an average level of 882.5 mg/m ^{3 as} a whole. When the maximum UV VOCs purification efficiency was reached, the CO ₂ concentration at the outlet of the UV device was basically maintained at a relatively stable level. That is to say 1531mg/m ³ , the new generation rate of CO2 after UV purification is stable at about 73.6%.

The CO ₂ concentration at the outlet of the adsorption device reached the maximum value of 1748 mg/m ³ after 360 seconds, and then remained at a relatively stable level of 1679 mg/m ³ , that is, the new CO ₂ generation rate of the combined purification stabilized at about 90.3%.

UV contrast at the purge outlet means and the adsorption means and a newly generated CO concentration ratio of _2, it is found, the new generation of CO concentration and the adsorption device ₂ is still a substantial increase, due to the ultraviolet rays from the apparatus outlet VOCs, O _3, After entering the adsorption zone, H ₂ O can be adsorbed on the outer surface of molecular sieve and activated carbon and the inner surface of the pores, and the catalytic oxidation and decomposition of VOCs will continue to generate CO ₂ , which further purifies the VOCs in the exhaust gas.

3.2.2.3 Comparison of PM 2.5 data at the beginning of combined purification and after the end of combined purification

Before the start of the formal combined purification experiment, the PM2.5 value in the 0.9m ³ /h and 1105mg/m ³ VOCs gas was 17μg/m ³ , and after the 7200s purification experiment, the PM2.5 value in the outlet gas of the adsorption device rose to 5580μg/m ³ , PM 2.5 increased nearly 300 times; meanwhile, a yellow oily liquid was formed at the lower end of the 21AE molecular sieve adsorption column of the adsorption device.

It shows that the polymerization degree of the photopolymerization reaction of VOCs during UV treatment is different, and the products are also different: part of the product is high molecular weight organic solid particles, which can be suspended in the gas and taken out of the UV purification unit with the airflow for discharge; the other part is liquid The state is deposited on the inner surface of the pipe.

In summary, the present invention effectively overcomes various shortcomings in the prior art and has high industrial value.

The above-mentioned embodiments only exemplarily illustrate the principles and effects of the present invention, and are not used to limit the present invention. Anyone familiar with this technology can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed in the present invention should still be covered by the claims of the present invention.

Claims

A gas processing system for VOCs in engine exhaust, including:

Inlet, outlet, and flow path between inlet and outlet;

It also includes an ultraviolet device and an exhaust electric field device, the ultraviolet device and the exhaust electric field device are sequentially arranged along the flow path from the inlet to the outlet;

The exhaust electric field device includes: an entrance of the electric field device, an exit of the electric field device, an electric field cathode and an electric field anode, and the electric field cathode and the electric field anode are used to generate an ionization dust removal electric field;

The ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is 1.667:1 to 1680:1.
The VOCs gas treatment system in engine exhaust according to claim 1, wherein the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is 6.67:1 to 56.67:1.
The VOCs gas treatment system in the engine exhaust according to claim 1 or 2, wherein the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is such that the coupling times of the ionization dust removal electric field ≤ 3 .
The VOCs gas treatment system in engine exhaust according to any one of claims 1 to 3, wherein the diameter of the electric field cathode is 1-3 mm, and the distance between the electric field anode and the electric field cathode is 2.5- 139.9 mm.
The VOCs gas treatment system in engine exhaust according to any one of claims 1-4, wherein the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode, the electric field anode and the The distance between the electric field cathodes, the length of the electric field anode and the length of the electric field cathode make the coupling times of the ionization dust removal electric field≤3.
A method for processing VOCs in engine exhaust gas includes the following steps:

UV treatment of VOCs gas to obtain products after UV treatment of tail gas;

The product after UV treatment exhaust gas is subjected to electric field dust removal treatment to remove particulate matter in the product after UV treatment exhaust gas;

The electric field dust removal treatment further includes a method for reducing the coupling of the dust removal electric field, and the method for reducing the coupling of the dust removal electric field includes the following steps:

It includes selecting the ratio of the dust collection area of the electric field anode to the discharge area of the electric field cathode so that the number of coupling times of the ionization electric field is ≤3.
The method for processing VOCs in engine exhaust gas according to claim 6, characterized in that it comprises selecting the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode to be 1.667:1 to 1680:1.
The method for treating VOCs in engine exhaust gas according to claim 6 or 7, characterized in that it comprises selecting the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode to be 6.67:1 to 56.67:1.
The method for processing VOCs in engine exhaust gas according to any one of claims 6-8, comprising selecting the diameter of the electric field cathode to be 1-3 mm, and the distance between the electric field anode and the electric field cathode is 2.5-139.9 mm.
The method for treating VOCs in engine exhaust gas according to any one of claims 6-9, wherein the ratio of the dust accumulation area of the electric field anode to the discharge area of the electric field cathode is selected, and the electric field anode and the discharge area of the electric field cathode are selected. The distance between the electric field cathodes, the length of the electric field anode, and the length of the electric field cathode make the coupling times of the ionization dust removal electric field≤3.
The method for processing VOCs in engine exhaust gas according to any one of claims 6-10, wherein the method for processing VOCs in engine exhaust gas further comprises adsorbing products after UV treatment of exhaust gas before electric field dust removal treatment deal with.
The method for processing VOCs in engine exhaust gas according to claim 11, wherein the adsorbent for the adsorption treatment is activated carbon and/or molecular sieve.
The method for treating VOCs in engine exhaust gas according to any one of claims 6-12, wherein the product after UV treatment of the exhaust gas contains nanoparticles, and the particulate matter in the product after removing the UV treatment exhaust gas comprises Remove the nanoparticles in the product after UV treatment.
The method for treating VOCs in engine exhaust gas according to any one of claims 6-13, wherein the product after UV treatment of the exhaust gas contains particles less than 50nm, and the product after removing the UV treatment exhaust gas contains The particulate matter includes particulate matter less than 50nm in the product after removing the UV treatment exhaust gas.
The method for processing VOCs in engine exhaust gas according to any one of claims 6-14, wherein the product after UV treatment of the exhaust gas contains 15-35 nanometer particles, and the product after removing the UV treatment exhaust gas The particulate matter in includes 15-35 nanometer particulate matter in the product after removing the UV treatment exhaust gas.
The method for treating VOCs in engine exhaust gas according to any one of claims 6-15, wherein the product after UV treatment of the exhaust gas contains 23nm particulate matter, and the particulate matter in the product after the UV treatment is removed Including the removal of 23nm particles in the product after UV treatment.
The method for processing VOCs in engine exhaust gas according to any one of claims 6-16, wherein the removal rate of 23nm particulate matter in the product after removing the UV-treated exhaust gas is ≥93%.
The method for treating VOCs in engine exhaust gas according to any one of claims 6-17, wherein the removal rate of 23nm particles in the product after removing the UV-treated exhaust gas is ≥ 95%.
The method for treating VOCs in engine exhaust gas according to any one of claims 6-18, wherein the removal rate of 23nm particles in the product after removing the UV-treated exhaust gas is ≥99.99%.