CN114653191A

CN114653191A - Baffling type plasma catalytic organic waste gas treatment device

Info

Publication number: CN114653191A
Application number: CN202011534739.2A
Authority: CN
Inventors: 李超; 宋项宁; 张海; 张福良; 赵乾斌; 朱骁; 郭亚逢
Original assignee: China Petroleum and Chemical Corp; Sinopec Qingdao Safety Engineering Institute
Current assignee: China Petroleum and Chemical Corp; Sinopec Qingdao Safety Engineering Institute
Priority date: 2020-12-22
Filing date: 2020-12-22
Publication date: 2022-06-24

Abstract

The invention relates to the field of waste gas treatment, and discloses a baffled plasma catalyzed organic waste gas treatment device, wherein the organic waste gas treatment device comprises a shell (3) with a first side wall (14) and a second side wall (15) which are opposite to each other, and a first electrode plate (1) and a second electrode plate (2) which are alternately arranged at intervals along the length direction of the shell (3), wherein the first electrode plate (1) is connected to the first side wall (14) and the second electrode plate (2) is connected to the second side wall (15) to form a baffled channel. Through the technical scheme, the length of the flow path of the waste gas in the shell is obviously increased, the retention time of the waste gas in the discharge space is increased, and the collision frequency of waste gas molecules and active particles is improved, so that the decomposition efficiency of the waste gas is improved, and the energy utilization rate is improved.

Description

Baffling type plasma catalytic organic waste gas treatment device

Technical Field

The invention relates to the field of waste gas treatment, in particular to a baffling type plasma catalytic organic waste gas treatment device.

Background

Volatile Organic Compounds (VOCs) are important precursors of regional atmospheric pollutants (ozone, aerosol and the like) in China, and seriously harm the natural environment and human health. In recent years, the treatment technology of VOCs has become a research hotspot in the field of air pollution control. Compared with the traditional combustion method, adsorption method and biological method, the low-temperature plasma technology is widely applied to the field of industrial waste gas treatment by virtue of the advantages of simple process, quick start and stop, low operation cost and the like, and is particularly suitable for malodorous and low-concentration organic waste gas with large gas amount, low concentration and no recovery value. In order to prevent gas and discharge from corroding electrodes, a double-dielectric barrier discharge form is mostly adopted in industrial application, and the reactor mainly comprises a shaft cylinder type, a calandria type and the like. The shaft-cylinder type configuration can generate a larger discharge space, is beneficial to VOCs reaction, and has larger pressure loss; the calandria configuration is suitable for high-speed airflow, but the narrow discharge space limits the reaction efficiency of VOCs; the flat panel type has the advantages of the two, but the realization of stable discharge requires higher input power.

In general, the dielectric barrier discharge plasma alone has problems of low decomposition efficiency, low energy efficiency, by-product generation, and the like.

Disclosure of Invention

The invention aims to provide an organic waste gas treatment device to solve the problems of low decomposition efficiency and low energy utilization efficiency.

In order to accomplish the above object, the present invention provides a baffled plasma catalyzed organic exhaust gas treatment device, wherein the organic exhaust gas treatment device comprises a case having a first sidewall and a second sidewall opposite to each other, and a plurality of first electrode plates and a plurality of second electrode plates alternately arranged at intervals along a length direction of the case, the first electrode plates being connected to the first sidewall and the second electrode plates being connected to the second sidewall to form a baffled passage.

Alternatively, the case includes third and fourth sidewalls opposite to each other, the first electrode plate is connected to the third and fourth sidewalls and spaced apart from the second sidewall, and the second electrode plate is connected to the third and fourth sidewalls and spaced apart from the first sidewall.

Optionally, the first electrode plate and the second electrode plate are respectively sleeved with a dielectric housing.

Optionally, the dielectric housing has an opening joined to the first sidewall or the second sidewall, an insulator is disposed between the first electrode plate and the first sidewall, and an insulator is disposed between the second electrode plate and the second sidewall.

Optionally, a porous catalytic member is disposed on the second sidewall and between the second electrode plates, and a catalyst is disposed in the porous catalytic member.

Alternatively, the porous catalytic member is provided at an end thereof facing the first electrode plate with two protrusions and a recess between the two protrusions, the media case of the first electrode plate being inserted into the recess.

Alternatively, manganese dioxide is provided in the porous catalytic member, and titanium dioxide is provided in a tip portion of the projection.

Optionally, the top surface of the protrusion is flush with the end surface of the first electrode plate.

Alternatively, the porous catalytic member is made by: preparing polyurethane foam; soaking polyurethane foam in the alumina slurry to make the slurry fully fill the pores of the polyurethane foam, and sintering to obtain foamed ceramic; soaking the foamed ceramic in manganese nitrate solution and then roasting to obtain load MnO₂The foamed ceramic of (1); to load MnO₂Partially immersed in TiO₂In sol, roasting to obtain TiO₂-MnO₂Foamed ceramics.

Optionally, the second side wall is provided with an openable door aligned with the porous catalytic member.

Optionally, the two ends of the housing along the length direction are respectively provided with an air inlet and an air outlet.

Optionally, there is one more second electrode plate than the first electrode plate, and an electrode protector is disposed on a side of the second electrode plate, which is the smallest distance from the gas inlet, facing the gas inlet.

Optionally, the electrode protector is attached to a side surface of the second electrode plate, and a thickness of the electrode protector in the first direction is tapered along a direction in which the second sidewall points to the first sidewall.

Optionally, the housing includes a main body portion provided with the first electrode plate and the second electrode plate, and tapered portions connected to two ends of the main body portion, and small ends of the two tapered portions are respectively provided with the air inlet and the air outlet.

Optionally, a gas distribution plate is disposed at an end of the main body portion facing the gas inlet, the gas distribution plate is provided with a first area, a second area and a third area, which are arranged along a direction in which the first sidewall faces the second sidewall, the first area is provided with a first through hole, the second area is provided with a second through hole, the third area is provided with a third through hole, and an inner diameter of the first through hole is smaller than an inner diameter of the second through hole and smaller than an inner diameter of the third through hole.

Optionally, the organic waste gas treatment device further comprises a power supply electrically connected to the first electrode plates, wherein the power supply outputs adjustable current in voltage amplitude, current amplitude, output waveform, frequency and duty ratio, and the power supply can output different currents to different first electrode plates, and the second electrode plate is grounded.

Optionally, in a direction from the gas inlet to the gas outlet, the power of the downstream first electrode plate is greater than or equal to the power of the upstream first electrode plate.

Through the technical scheme, the length of the flow path of the waste gas in the shell is obviously increased, the retention time of the waste gas in the discharge space is increased, and the collision frequency of waste gas molecules and active particles is improved, so that the decomposition efficiency of the waste gas is improved, and the energy utilization rate is improved.

Drawings

FIG. 1 is a schematic structural diagram of a baffled plasma catalyzed organic exhaust treatment device according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of an electrode plate and a dielectric housing according to an embodiment of the present invention;

FIG. 3 is a schematic structural view of a porous catalytic member according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a gas distribution plate according to an embodiment of the present invention;

fig. 5 is a schematic view of the internal structure of three different configurations of the exhaust gas treatment device.

Description of the reference numerals

1-a first electrode plate, 2-a second electrode plate, 3-a shell, 4-a dielectric shell, 5-a porous catalytic member, 6-a bulge, 7-an electrode protector, 8-a gas inlet, 9-a gas outlet, 10-a main body part, 11-a tapered part, 12-a gas distribution plate, 13-a power supply, 14-a first side wall, 15-a second side wall, 16-a door.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

The invention provides a baffled plasma catalyzed organic waste gas treatment device, wherein the organic waste gas treatment device comprises a shell 3 with a first side wall 14 and a second side wall 15 which are opposite to each other, and a plurality of first electrode plates 1 and a plurality of second electrode plates 2 which are alternately arranged along the length direction of the shell 3, wherein the first electrode plates 1 are connected to the first side wall 14, and the second electrode plates 2 are connected to the second side wall 15 to form a baffled channel.

The case 3 is a container structure for containing the exhaust gas flowing along the length direction thereof, and includes a pair of sidewalls, i.e., a first sidewall 14 and a second sidewall 15, opposite to each other, and the first electrode plate 1 and the second electrode plate 2 can discharge electricity when being energized, with a discharge space formed therebetween, such that the exhaust gas is decomposed in the discharge space. Wherein, the first electrode plates 1 and the second electrode plates 2 are alternately arranged along the length direction (corresponding to the whole flow direction of the exhaust gas), and the first electrode plates 1 are connected to the first side wall 14 (and spaced from the second side wall 15), and the second electrode plates 2 are connected to the second side wall 15 (and spaced from the first side wall 14), so that a baffling channel can be formed in the shell 3, the exhaust gas flow will alternately bypass the first electrode plates 1 and the second electrode plates 2, the flow path thereof is approximately S-shaped, which enables the length of the flow path of the exhaust gas in the shell 3 to be obviously increased, the residence time of the exhaust gas in the discharge space to be increased, the collision frequency of the exhaust gas molecules and the active particles to be increased, thereby improving the decomposition efficiency of the exhaust gas and improving the energy utilization rate.

In addition, the case 3 includes third and fourth sidewalls opposite to each other, the first electrode plate 1 is connected to the third and fourth sidewalls and spaced apart from the second sidewall 15, and the second electrode plate 2 is connected to the third and fourth sidewalls and spaced apart from the first sidewall 14. That is, the portion where the first electrode plate 1 and the second electrode plate 2 are disposed may be formed by four side walls to form a structure with a quadrilateral cross section, the first electrode plate 1 and the second electrode plate 2 are substantially quadrangular plate members, an opening for allowing the gas flow to pass is formed between the first electrode plate 1 and the second side wall 15, and an opening for allowing the gas flow to pass is formed between the second electrode plate 2 and the first side wall 14, so that a baffled passage is formed, so that the gas flow can flow therein in a baffled manner, that is, along an S-shaped path.

In addition, the first electrode plate 1 and the second electrode plate 2 are respectively sleeved with a dielectric housing 4. The electrode plate can be made of conductive metals such as copper, iron and tungsten, can be arranged in the cuboid cavity in the dielectric shell 4, and has no obvious gap between the two. The dielectric housing 4 can be made of dielectric materials such as quartz and ceramic, can reduce the discharge intensity, increases the discharge area, can protect the first electrode plate 1 and the second electrode plate 2, and avoids the direct contact with the discharge current on the surfaces of the electrode plates. Preferably, the dielectric housing 4 is made of quartz, and may be surrounded by a plurality of quartz plates.

Further, the dielectric housing 4 has an opening joined to the first sidewall 14 or the second sidewall 15, an insulating member located in the opening is disposed between the first electrode plate 1 and the first sidewall 14, and an insulating member located in the opening is disposed between the second electrode plate 2 and the second sidewall 15. The electrode plates are formed substantially in a hexahedral shape, and the dielectric housing 4 is also formed substantially in a hexahedral shape, so that the electrode plates can be accommodated inside the dielectric housing 4, as shown with reference to fig. 2; and the dielectric housing 4 is formed with an opening that is joined to the first side wall 14 or the second side wall 15, and the electrode plate is separated from the first side wall 14 or the second side wall 15 by an insulating member, which may be an insulating structure for insulating aerosol formation. In this configuration, the dielectric housing 4 for the first electrode plate 1 is fastened to the first sidewall 14, the insulator at the opening of the dielectric housing 4 may separate the first electrode plate 1 from the first sidewall 14, similarly, the dielectric housing 4 for the second electrode plate 2 is fastened to the second sidewall 15, and the insulator at the opening of the dielectric housing 4 may separate the second electrode plate 2 from the second sidewall 15.

In addition, the second side wall 15 is provided with a porous catalyst member 5 located between the second electrode plates 2, and a catalyst is provided in the porous catalyst member 5. As shown in fig. 1, a porous catalytic member 5 is disposed between two adjacent second electrode plates 2, and exhaust gas bypassing the end of the first electrode plate 1 facing the second side wall 15 can enter the porous catalytic member 5 and undergo decomposition reaction under the action of a catalyst therein.

Wherein one end of the porous catalytic member 5 facing the first electrode plate 1 is provided with two protrusions 6 and a recess between the two protrusions 6, into which the dielectric housing 4 of the first electrode plate 1 is inserted. Referring to fig. 3, a recess is formed between the two protrusions 6 to allow the medium housing 4 on the first electrode plate 1 to be inserted into the porous catalyst member 5, which causes the space near the end of the first electrode plate 1 facing the second side wall 15 to be occupied by the porous catalyst member 5, the exhaust gas flow cannot directly bypass the first electrode plate 1, and the exhaust gas can be forced to pass through the porous catalyst member 5 to be sufficiently in contact with the catalyst therein.

Further, manganese dioxide is provided in the porous catalyst member 5, and titanium dioxide is provided in the tip end portion of the protruding portion 6. The pore surface of the porous catalytic member 5 of the porous structure is provided with manganese dioxide, and in the projections 6 located on both sides of the first electrode plate 1, the pore surface of the tip portion thereof is provided with titanium dioxide. Wherein the top end part of the protruding part 6 is close to the discharge area between the two electrode plates, the titanium dioxide can generate strong oxide particle hydroxyl radical by using the ultraviolet light generated by the discharge to catalyze and oxidize non-mineralized Volatile Organic Compounds (VOCs), and when the waste gas enters into other parts of the porous catalytic member 5, MnO is added₂Ozone generated by discharge is decomposed into oxygen free radicals, and VOCs are further catalyzed and oxidized to be thoroughly decomposed. In addition, input power through adjusting different electrodes can guarantee that VOCs degradation efficiency promotes the time, reduces energy consumption to make full use of ultraviolet ray and ozone etc. accessory substance that discharge and produce improve the synergistic effect of plasma and catalyst. Wherein, the thickness of the top part is 2-5mm, and the loading capacity of the titanium dioxide is 2-10%; MnO (MnO)₂The loading amount is 6-15%.

Wherein the top surface of the protruding part 6 is flush with the end surface of the first electrode plate 1. Wherein the dielectric housing 4 has a thickness which can be partially inserted into the recess, and the first electrode plate 1 is not inserted into the recess, and the end surface thereof is kept flush with the top surface of the projection 6, which makes the projection 6 sufficiently adjacent to the discharge region formed between the first electrode plate 1 and the second electrode plate 2, of course, the projection 6 does not enter the discharge region, avoiding affecting the discharge between the two electrode plates.

Wherein the porous catalytic member 5 is produced by the following method: preparing polyurethane foam; soaking polyurethane foam in the alumina slurry to make the slurry fully fill the pores of the polyurethane foam, and sintering to obtain foamed ceramic; soaking the foamed ceramic in manganese nitrate solution and then roasting to obtain load MnO₂The foamed ceramic of (1); to load MnO₂Partially immersed in TiO₂In sol, roasting to obtain TiO₂-MnO₂Foamed ceramics. That is, polyurethane foam is used as a framework, alumina slurry is filled into the framework and then sintered into foamed ceramic, and then MnO is loaded₂And TiO₂。

Specifically, the manufacturing method of the porous catalytic member 5 is as follows: (1) processing polyurethane foam into a corresponding concave shape, soaking and kneading for 2h by using a sodium hydroxide solution (12 percent, wt), cleaning, and soaking in a sodium carboxymethylcellulose solution (2 percent, wt) for 1 h; soaking the pretreated polyurethane foam in the slurry for repeated extrusion and kneading until the slurry is completely filled in polyurethane foam pores; extruding the polyurethane foam coated with the slurry out of redundant slurry through a roller press, and drying for 24-36h at the temperature of 60-80 ℃ to obtain a foamed ceramic biscuit; placing the foam ceramic biscuit into a high-temperature furnace, sintering for 2-3h at 1300-1500 ℃, and cooling at room temperature to obtain foam ceramic; (2) soaking the foamed ceramic in a manganese nitrate solution (12-31 wt%) for 1h, taking out, drying, soaking, and repeating the same operation for 6-10 times; placing the completely soaked foamed ceramic in a muffle furnace for roasting at 500-600 ℃ for 4-8h, and cooling at room temperature to obtain supported MnO₂The foamed ceramic of (1); (3) to load MnO₂The top end part of the convex part of the foamed ceramic is immersed in the TiO₂Ultrasonically oscillating for 2min in the sol, taking out, drying for 1h at 105 ℃, and repeating the same operation for 6-10 times; roasting at 600-700 ℃ for 2h, and cooling at room temperature to obtain TiO₂-MnO₂Ceramic foam, i.e. porous catalytic member 5. The preparation method of the slurry comprises the following steps:respectively adding 10-40% of alumina powder, 30-50% of zirconia powder, 0.3-0.6% of gum arabic, 0.2-0.4% of polyacrylamide and 0.3-0.7% of carboxymethyl cellulose into deionized water, uniformly stirring, placing in a ball mill (rotating speed 500r/min) for ball milling for 6-10h, taking out, and standing for 36-48 h. TiO 2₂The sol preparation process comprises the following steps: mixing tetrabutyl titanate and absolute ethyl alcohol according to the volume ratio of 1:3-1:6, stirring for 1h at 400r/min, adding a proper amount of hydrochloric acid to adjust the pH value of the solution to be less than or equal to 3, and obtaining TiO₂And (3) sol.

Wherein the second side wall 15 is provided with an openable door 16 in a position aligned with the porous catalytic member 5. Referring to fig. 1, the housing 3 may have a length direction corresponding to a horizontal direction, a first side wall 14 may be positioned at an upper side, a second side wall 15 may be positioned at a lower side, and an openable door 16 is formed on the second side wall 15 to allow the porous catalyst member 5 to be taken out or put in.

Wherein, the two ends of the housing 3 along the length direction are respectively provided with an air inlet 8 and an air outlet 9. After entering the housing 3 through the inlet 8, the exhaust gas flows substantially in the longitudinal direction, and bypasses the first electrode plate 1 and the second electrode plate 2 in sequence, and finally is discharged through the outlet 9.

The number of the second electrode plates 2 is one more than that of the first electrode plates 1, and an electrode protector 7 is provided on a side surface of the second electrode plate 2, which is the smallest distance from the gas inlet 8, facing the gas inlet 8. The porous catalytic member 5 is disposed between the two second electrode plates 2, and the number thereof is the same as that of the first electrode plates 1, so that the number of the second electrode plates 2 is one more, so that the second electrode plates 2 are disposed on both sides of each of the first electrode plates 1, and the electrode protecting member 7 is disposed on the side of the second electrode plate 2 directly facing the air inlet 8, thereby preventing the exhaust gas from directly impacting the second electrode plates 2. Of course, the electrode protector 7 may also be provided on the side of the second electrode plate 2 directly facing the gas outlet 9. The side surfaces of the second electrode plate 2 where the electrode protector 7 is provided are all surfaces where substantially no discharge occurs. The electrode protector 7 is made of a corrosion-resistant material such as polyvinyl chloride or polypropylene.

Wherein the electrode protector 7 is attached to the side surface of the second electrode plate 2, and the thickness of the electrode protector 7 in the first direction is tapered along the direction in which the second side wall 15 points to the first side wall 14. The electrode protector 7 may consist of two angled rectangular plates, one of which fits against the second electrode plate 2 and the other of which forms an acute angle with the second electrode plate 2, which may be 30 °, which results in the electrode protector 7 also forming between the second side walls 14 substantially 120 °, which may result in the gas flow bypassing the second electrode plate 2 along the inclined surface of the electrode protector 7.

The housing 3 includes a main body 10 provided with the first electrode plate 1 and the second electrode plate 2, and tapered portions 11 connected to two ends of the main body 10, and small ends of the two tapered portions 11 are respectively provided with the air inlet 8 and the air outlet 9. As shown in fig. 1, the housing 3 mainly includes a main body 10 as a reaction body and two tapered portions 11 at both ends, wherein the main body 10 has a size of approximately 600mm × 200mm × 100mm, the tapered portion 11 at the gas inlet 8 can diffuse gas from the pipeline, and the tapered portion 11 at the gas outlet 9 can converge processed gas for discharge.

The main body portion 10 is provided with a gas distribution plate 12 at an end facing the gas inlet 8, the gas distribution plate 12 is provided with a first area, a second area and a third area which are arranged along a direction of the first side wall 14 facing the second side wall 15, the first area is provided with a first through hole, the second area is provided with a second through hole, the third area is provided with a third through hole, and an inner diameter of the first through hole is smaller than an inner diameter of the second through hole. A gas distribution plate 12 is located between the electrode plates and the gas inlet 8 so that the gas is distributed in a suitable manner by the gas distribution plate 12 before reaching the electrode plates. Referring to fig. 4, the gas distribution plate 12 is divided into three areas with different inner diameters of the through holes, wherein the inner diameter of the through holes is 3-5mm, 7-10mm and 12-15mm, which allows more gas to be distributed in the area near the second sidewall 15, allowing a longer path for the gas to flow from the second sidewall 15 to the first sidewall 14 before the gas first bypasses the second electrode plate 2.

In addition, the organic waste gas treatment device further comprises a power supply 13 electrically connected with the first electrode plate 1, wherein the voltage amplitude, the current amplitude, the output waveform, the frequency and the duty ratio of the output current of the power supply 13 can be adjusted, the power supply 13 can output different currents to different first electrode plates 1, and the second electrode plate 2 is grounded. As shown in fig. 1, the number of the first electrode plates 1 is 4, and the power supply 13 can correspondingly output four different currents, so that the four electrode plates 1 discharge in different manners to meet the discharge requirements at different positions.

Wherein, in the direction from the gas inlet 8 to the gas outlet 9, the power of the downstream first electrode plate 1 is greater than or equal to the power of the upstream first electrode plate 1. The first electrode plates 1 are arranged along the direction from the gas inlet 8 to the gas outlet 9, and the power output from the power supply 13 to the downstream first electrode plate 1 is greater than or equal to the power of the upstream first electrode plate 1, so that the decomposition efficiency of the organic waste gas can be improved.

Examples of this and other comparative schemes will be described below.

Experiment one

As shown in fig. 5, three different similar exhaust gas treatment devices are provided, wherein 1 is a calandria electrode: the length of the electrode tube is 150mm, the medium of the electrode tube is quartz, the wall thickness is 1.5mm, the internal metal electrode is columnar iron, the length is 130mm, the diameter is 5mm, and the gap between the electrode tubes is 8 mm; 2 is a row plate type electrode: the electrode plate has the size of 150mm multiplied by 80mm multiplied by 10mm, the electrode plate medium is quartz, the internal metal electrode is a cuboid iron block, and the size is 130mm multiplied by 76mm multiplied by 7 mm; 3 is the baffling formula electrode structure of this scheme: the size of the main body part is 600mm multiplied by 200mm multiplied by 100mm, 9 plate electrodes are arranged in the main body part, wherein 4 high-voltage electrodes are arranged on a first side wall 14 at the top, 5 grounding electrodes are arranged on a second side wall 15 at the bottom, the size of the electrode plate is 150mm multiplied by 80mm multiplied by 10mm, a quartz shell (a dielectric shell 4) is sleeved, the inner metal electrode is a cuboid iron block with the size of 130mm multiplied by 76mm multiplied by 7mm, 4 porous catalytic parts 5 are arranged on the second side wall 15, namely TiO₂-MnO₂Foamed ceramic, TiO 2 each₂-MnO₂The dimensions of the ceramic foam are 100mm by 26mm by 52mm, whichThe size of the top recess is 84mm multiplied by 26mm multiplied by 5 mm; wherein, Al₂O₃MnO of foamed ceramics₂Loading of 11%, TiO₂The loading is 5 percent and is provided with TiO₂The height of the top portion of the catalyst was 3 mm.

The three plasma configuration reactors are all connected with a high-frequency alternating current power supply, and the output discharge power is divided into three grades: 105W, 187W and 234W. Keeping the intake flow at 20m³H, the concentration of benzene is 350 +/-20 mg/m³. The efficiency of benzene degradation and energy utilization by three plasma configuration reactors is shown in table 1. .

TABLE 1

As can be seen from table 1, the benzene degradation efficiency and energy utilization efficiency of the calandria configuration are slightly higher than about 3% and 6% of the calandria configuration when the discharge power is 105W; when the discharge power is increased to 187W and 234W, respectively, the benzene degradation efficiency of the plate-type configuration is about 2% and 6% higher than that of the calandria type, and the energy utilization efficiency of the plate-type configuration is about 4% and 4% higher than that of the calandria type. This shows that the configuration of the calandria type is superior to the calandria type when the discharge power is sufficiently high. Under the same discharge power, compared with a plate-type configuration, the benzene degradation efficiency of the baffled configuration is respectively improved by 39%, 26% and 27%; the energy utilization efficiency of the baffled configuration is improved by 34%, 33% and 31% respectively. The result fully shows that the plate-type electrode is designed into a baffling structure, so that the degradation efficiency and the energy utilization efficiency of the plasma reactor on VOCs can be effectively improved under the condition of unchanged discharge power.

Experiment two

The following embodiments 1-9 all adopt the exhaust gas treatment device of this scheme, wherein, the size of the main part is 600mm × 200mm × 100mm, 9 plate electrodes are provided in the main part, 4 high voltage electrodes are installed on the first side wall 14 of the top, 5 grounding electrodes are installed on the second side wall 15 of the bottom, the size of the electrode plate is 150mm × 80mm × 10mm, the quartz casing 4 is sleeved, the internal metal electrode is a rectangular parallelepiped iron block, and the size is 130mm × 76mm × 7 mm.

Example 1

The output discharge power was 314W, and the intake air was air.

Example 2

The benzene concentration in the feed gas was 100. + -.5 ppm.

Example 3

4 pieces of porous catalytic members 5, i.e., ceramic foams, each having a size of 100mm × 26mm × 52mm and a size of a recess at the top thereof having a size of 84mm × 26mm × 5mm, are provided on the second side wall 15; wherein MnO of the foamed ceramics₂The supported amount was 11%.

Example 4

The ceramic foam of example 3 was replaced by MnO₂The loading is 7 percent of foamed ceramic.

Example 5

The ceramic foam of example 3 was replaced by MnO₂The loading is 11 percent of foamed ceramic.

Example 6

The ceramic foam of example 3 was replaced by MnO₂The loading is 13 percent of foamed ceramic.

Example 7

MnO of example 5₂The foamed ceramic with the loading of 11 percent is replaced by TiO₂2% loading and MnO₂11% loading of foamed ceramic, TiO₂The height of the tip portion of (a) is 2 mm.

Example 8

MnO of example 5₂The foamed ceramic with the loading of 11 percent is replaced by TiO₂A loading of 5% and MnO₂11% loading of foamed ceramic, TiO₂The height of the tip portion of (a) is 3 mm.

Example 9

MnO of example 5₂The foamed ceramic with the loading of 11 percent is replaced by TiO₂A loading of 8% and MnO₂11% loading of foamed ceramic, TiO₂The height of the tip portion of (a) is 4 mm.

The experimental results of examples 1 to 9 are shown in Table 2 below.

TABLE 2

As can be seen from Table 2, the supported TiO₂-MnO₂After the double active components, the benzene degradation efficiency and the energy efficiency are obviously improved, and the ozone yield is further reduced, wherein MnO is used₂Loading of 11% and TiO₂The synergistic effect of the foamed ceramic with the load of 5% is optimal, the benzene degradation efficiency and the energy utilization efficiency are respectively improved by 75% and 70% compared with the experimental group 2, the outlet ozone concentration is obviously reduced, and the ozone amount is reduced by 61% compared with the experimental group 2. Hence, being MnO₂Loading 11% and TiO₂A ceramic foam with a loading of 5% is the most preferred porous catalytic member 7.

Experiment three

The following embodiments 1 to 9 all adopt the exhaust gas treatment device of this scheme, wherein, the size of the main part is 600mm × 200mm × 100mm, is provided with 9 plate electrodes in the main part, and wherein 4 high voltage electrodes are installed at the first lateral wall 14 of top, and 5 earthing electrodes are installed at the second lateral wall 15 of bottom, and the electrode plate size is 150mm × 80mm × 10mm, overlaps and establishes quartz envelope 4, and interior metal electrode is cuboid iron plate, and the size is 130mm × 76mm × 7 mm.

Wherein, the power of the four first electrode plates 1 from the gas inlet 8 to the gas outlet 9 is P1, P2, P3 and P4 respectively.

On the second side wall 15 are arranged 4 porous catalytic elements 5, i.e. TiO₂-MnO₂Foamed ceramic, TiO 2 each₂-MnO₂The dimension of the foamed ceramic is 100mm multiplied by 26mm multiplied by 52mm, and the dimension of the top dent is 84mm multiplied by 26mm multiplied by 5 mm; wherein, Al₂O₃MnO of foamed ceramics₂Loading of 11%, TiO₂The loading is 5 percent and is provided with TiO₂The height of the top portion of the catalyst was 3 mm.

In the following Table 3, experimental data of examples 10 to 21 are shown.

TABLE 3

Before the waste gas enters the reactor, the concentration and the composition of the waste gas are analyzed according to a preposed gas on-line monitor, and the following conditions are determined: (1) lower concentration of organic waste gas (C)_voc≤500mg/m³) Mainly comprises easily degradable components such as olefin, aldehyde, acid and the like; (2) the concentration of organic waste gas is lower (C)_voc≤500mg/m³) Mainly comprises refractory components such as alkane, benzene series and the like; (3) the concentration of the organic waste gas is higher (500 mg/m)³≤C_voc≤2000mg/m³) Mainly comprises easily degradable components such as olefin, aldehyde, acid and the like; (4) the concentration of the organic waste gas is higher (500 mg/m)³≤C_voc≤2000mg/m³) Mainly comprises refractory components such as alkane, benzene series and the like. According to the monitoring results, the output voltage and current of the power supplies P1-P4 are controlled, thereby adjusting the output power of P1, P2, P3 and P4 (assuming that the power supplies are divided into 165W, 237W and 314W).

The best power control mode is obtained by comparing the treatment efficiency of different P1-P4 combinations on four typical exhaust gas conditions. The detailed experimental protocol is shown in table 3.

As can be seen from Table 3, the combination of butane and propylene concentrations was selected to be 45mg/m³And 389mg/m³、413mg/m³And 58mg/m³、278mg/m³And 984mg/m³、861mg/m³And 352mg/m³4 typical cases of exhaust gas were simulated. The degradation effect of 3 power source combinations on mixed VOCs is examined, wherein the mode (mode one) of gradually increasing discharge power is adopted in the embodiment 10, the embodiment 13, the embodiment 16 and the embodiment 19, namely P1 ≦ P2 ≦ P3 ≦ P4; example 11, example 14, example 17 and example 20 employed a mode (mode two) in which the discharge power was gradually decreased, that is, P1. gtoreq.P 2. gtoreq.P 3. gtoreq.P 4; example 12, example 15, example 18 and example 21 all employed the maximumThe discharge power, i.e., P1, P2, P3, P4, is the maximum (mode three).

For different exhaust gas compositions, the degradation effects of the three power supply combinations on butane and propylene are shown as follows: mode one is slightly lower than mode three, but significantly higher than mode two. On the other hand, mode one consumes much less power than mode three. Therefore, the mode one, namely the mode that the discharge power of P1 ≦ P2 ≦ P3 ≦ P4 is gradually increased can be determined, and the optimal power supply operation mode with energy saving and efficiency improvement is realized.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, numerous simple modifications can be made to the technical solution of the invention, including combinations of the specific features in any suitable way, and the invention will not be further described in relation to the various possible combinations in order to avoid unnecessary repetition. Such simple modifications and combinations should be considered within the scope of the present disclosure as well.

Claims

1. A baffled plasma catalyzed organic exhaust gas treatment device, characterized in that the organic exhaust gas treatment device comprises a housing (3) having a first sidewall (14) and a second sidewall (15) opposite to each other, and a plurality of first electrode plates (1) and a plurality of second electrode plates (2) alternately arranged at intervals in a length direction of the housing (3), the first electrode plates (1) being connected to the first sidewall (14) and the second electrode plates (2) being connected to the second sidewall (15) to form a baffled channel.

2. A baffled plasma catalysed organic exhaust gas treatment device according to claim 1, wherein the housing (3) comprises third and fourth side walls opposite each other, the first electrode plate (1) being connected to the third and fourth side walls and spaced from the second side wall (15), the second electrode plate (2) being connected to the third and fourth side walls and spaced from the first side wall (14).

3. A baffled plasma catalyzed organic exhaust gas treatment device according to claim 1, wherein the first electrode plate (1) and the second electrode plate (2) are respectively sheathed with a dielectric housing (4).

4. A baffled plasma catalysed organic exhaust gas treatment device according to claim 3, wherein the media enclosure (4) has an opening bonded to the first side wall (14) or the second side wall (15), an insulator is provided between the first electrode plate (1) and the first side wall (14) in the opening, and an insulator is provided between the second electrode plate (2) and the second side wall (15) in the opening.

5. A baffled plasma catalysed organic exhaust gas treatment device according to claim 3, wherein the second side wall (15) is provided with a porous catalytic member (5) between the second electrode plates (2), the porous catalytic member (5) having a catalyst disposed therein.

6. A baffled plasma catalysed organic exhaust gas treatment device according to claim 5, wherein the porous catalytic member (5) is provided with two protrusions (6) and a recess between the two protrusions (6) at an end towards the first electrode plate (1), the media housing (4) of the first electrode plate (1) being inserted into the recess.

7. A baffled plasma catalysed organic exhaust gas treatment device according to claim 6, wherein manganese dioxide is provided in the porous catalytic member (5) and titanium dioxide is provided in a top portion of the protrusions (6).

8. A baffled plasma catalysed organic exhaust gas treatment device according to claim 7, wherein the top surface of the protrusions (6) is flush with the end face of the first electrode plate (1).

9. A baffled plasma catalyzed organic exhaust gas treatment device according to claim 8, wherein the porous catalytic member (5) is made by:

preparing polyurethane foam;

soaking the polyurethane foam in the alumina slurry to enable the slurry to fill the pores of the polyurethane foam, and sintering to obtain foamed ceramic;

soaking the foamed ceramic in manganese nitrate solution and then roasting to obtain load MnO₂The foamed ceramic of (1);

to load MnO₂Partially immersed in TiO₂In sol, roasting to obtain TiO₂-MnO₂Foam ceramic.

10. A baffled plasma catalysed organic exhaust gas treatment device according to claim 5, wherein the second side wall (15) is provided with an openable door (16) in alignment with the porous catalytic member (5).

11. A baffled plasma catalysed organic exhaust gas treatment device according to claim 1, characterised in that the housing (3) is provided with an air inlet (8) and an air outlet (9) at each end in the length direction.

12. A baffled plasma catalysed organic exhaust gas treatment device according to claim 11, wherein one more second electrode plate (2) than the first electrode plate (1), the side of the second electrode plate (2) having the smallest distance to the gas inlet (8) facing the gas inlet (9) being provided with an electrode protection (7).

13. A baffled plasma catalysed organic exhaust gas treatment device according to claim 12, wherein the electrode guard (7) is attached to a side face of the second electrode plate (2), and the thickness of the electrode guard (7) in the first direction tapers along the direction in which the second sidewall (15) points towards the first sidewall (14).

14. A baffled plasma catalyzed organic exhaust gas treatment device according to claim 12, wherein the housing (3) comprises a main body portion (10) provided with the first electrode plate (1) and the second electrode plate (2) and tapered portions (11) connected to both ends of the main body portion (10), and the small ends of the two tapered portions (11) are respectively provided with the gas inlet (8) and the gas outlet (9).

15. A baffled plasma catalyzed organic exhaust gas treatment device according to claim 14, wherein the end of the main body portion (10) facing the inlet port (8) is provided with a gas distribution plate (12), the gas distribution plate (12) is provided with a first area, a second area and a third area arranged along the first sidewall (14) in a direction towards the second sidewall (15), the first area is provided with a first through hole, the second area is provided with a second through hole, the third area is provided with a third through hole, and the inner diameter of the first through hole is smaller than the inner diameter of the second through hole and smaller than the inner diameter of the third through hole.

16. A baffled plasma catalyzed organic exhaust gas treatment device according to claim 11, further comprising a power source (13) electrically connected to the first electrode plate (1), wherein the power source (13) outputs a current with adjustable voltage amplitude, current amplitude, output waveform, frequency and duty ratio, and the power source (13) outputs different currents to different first electrode plates (1), and the second electrode plate (2) is grounded.

17. A baffled plasma catalysed organic exhaust gas treatment device according to claim 16, wherein the power of the downstream first electrode plate (1) is greater than or equal to the power of the upstream first electrode plate (1) in the direction of the gas inlet (8) towards the gas outlet (9).