JPH03503503A - Method and device for treating exhaust gas by electron beam irradiation - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Five fields of exhaust gas treatment methods and equipment by electron beam irradiation This invention irradiates exhaust gas containing harmful (gas) components such as SO□ and NO8 with an electron beam. and remove the harmful (gas) components from mist (sulfuric acid and/or nitric acid) or dust (ammonium sulfate and/or nitric acid). or ammonium nitrate) and capture the resulting mist and dust with a dust collector, etc. The present invention relates to a method and device for treating exhaust gas.

■Amount of skill distortion One method of exhaust gas treatment is to remove harmful (gas) components such as SO□ and NOl from exhaust gas. Exhaust gas is irradiated with electron beams to remove O radicals and OH radicals from oxygen, water, etc. in exhaust gas. These active species act on the harmful (gas) components in the exhaust gas to reduce emissions. This mist is further converted to dust in the presence of ammonia, etc., and then this mist is This method captures the mist and dust with a dust collector, etc.

Figure 1 shows the electron beam irradiation part of the exhaust gas treatment equipment used to implement this exhaust gas treatment method. Shows the general structure. As shown in the figure, an irradiation window 2 is provided in the exhaust gas duct 1, and the irradiation window 2 The electron beam 4 emitted from the electron beam accelerator 3 is passed through the exhaust gas duct 1. Irradiates the gas directly. , with a structure in which the electron beam 4 is directly irradiated into the inside of the exhaust gas duct 1. In this case, the amount of exhaust gas increases to a practical scale, and the size of exhaust gas duct 1 changes accordingly. When the size increases, in order to absorb the electron beam 4 without leaking into the exhaust gas, the exhaust gas duct must be A large number of electron beam accelerators 3 (two in the example in the figure) are used around the outer circumference of 1, and the dotted line 5 It was necessary to increase the maximum range of the electron beam 4 shown. However, many Installing 3 electron beam accelerators will complicate the structure of the exhaust gas treatment equipment and increase costs. There are drawbacks to increasing the Furthermore, in order to increase the maximum range of the electron beam 4, It is necessary to increase the speed voltage, which significantly increases the cost of the electron beam accelerator 3. become. In addition, when electron beams are accelerated with high voltage, high-energy X-rays are generated. , to block such high-energy X-rays, thick lead or concrete walls, etc. This also results in an increase in the total cost of the exhaust gas treatment equipment. .

That is, the prior art has various problems.

Table 1 below shows the maximum range of the electron beam, the size of the electron beam irradiation chamber, and the exhaust gas depending on the accelerating voltage. The relationship between the current velocity and the thickness of the ship wall that shields high-energy X-rays is shown.

800 3, 1 3.2 2.5xlO' 170500 1.6 1.7 6 xlO' 90300 0.8 0.9 2 xlO’ 34200 0.46 0.5 0.7 s 10’ 　　　　　　　P3 Table 1 above shows the maximum range of the electron beam and the electrons required for the exhaust gas to absorb the electron beam. This shows an example of the size of the irradiation chamber, and the amount of exhaust gas that can be treated with it. The thickness of the ship wall for shielding X-rays, that is, the shielding structure is determined. 302 and To treat harmful gas components such as NOx, an appropriate level of electron beam energy (acceleration voltage) is required. xi style) is required. However, the current flows through the thickness of the ship's wall, which shields the X-rays. Not an important factor in the decision.

JP 49-96975, JP 55-97232, U.S. Patent No. 4.507.2 No. 65 and No. 4.596.642, including those disclosed in the specifications of There are technologies that aim to irradiate the entire area with a uniform electron beam, but the above-mentioned problems arise. It is important to note that there is no complete solution to the problem.

Furthermore, in JP-A-61-68126, atmospheric air is introduced into an electron beam irradiation reactor. technology to irradiate the air in front of it with an electron beam to form ozone and oxygen atoms inside has been disclosed. has been done. The above-mentioned air containing ozone and oxygen atoms is mixed with the exhaust gas. of NO is oxidized to N O2, and then the exhaust gas is introduced into a wet absorption tower for desulfurization and denitrification. It is.

Desulfurization and denitrification using this technology use a wet absorption tower, so The absorbent liquid contains a large amount of nitrogen and sulfur compounds that are difficult to treat. requires expensive wastewater treatment equipment. Therefore, installation and maintenance are expensive. Expensive problems arise.

The present invention is directed to solving the aforementioned problems of the prior art. From the mainstream of exhaust gas A part of the sample is extracted, and a low-voltage accelerator is used to irradiate it with an electron beam. Active species such as O radicals and OH radicals are formed in the gas and activated. The activated exhaust gas is uniformly supplied into the main stream of the exhaust gas, thereby removing the How to treat exhaust gas by electron beam irradiation that effectively removes 302 and NOl It is an object of the present invention to provide a method and apparatus.

courage In order to achieve the above object, the present invention irradiates a part of the exhaust gas to be treated with an electron beam, Forming active species such as O radicals and OH radicals in the irradiated exhaust gas 1. The exhaust gas in which active species have been formed is mixed with the exhaust gas to be treated, thereby Converting harmful (gas) components in gas into mist or dust by the action of active species , and an exhaust gas treatment method comprising capturing the mist and dust.

The present invention relates to an electron beam irradiation chamber for irradiating electron beams from an electron beam accelerator, and A portion of the gas is introduced into an electron beam irradiation chamber, where the exhaust gas is irradiated with an electron beam to generate O radicals. Exhaust gas that forms active species such as radicals and Or (radicals), and has active species formed inside. Supply equipment and supplies for supplying gas to the exhaust gas main duct through which the exhaust gas to be treated flows. Dispersion for uniformly dispersing the exhaust gas supplied from the supply unit into the exhaust gas main duct Exhaust in the main duct that has changed into dust due to the action of equipment and active species. Exhaust gas treatment equipment consisting of a capture device to capture harmful (gas) components in gas We also provide a location.

Section @ simple explanation FIG. 1 shows a schematic structure of an electron beam irradiation section of a conventional exhaust gas system.

Figure 2 shows the general structure of an exhaust gas treatment device for carrying out the exhaust gas treatment method of the present invention. vinegar.

FIG. 3 is a sectional view taken along line XX in FIG. 2.

Figure 4 shows an outline of another exhaust gas treatment device for carrying out the exhaust gas treatment method of the present invention. Shows the essential structure.

FIG. 5 is a sectional view taken along YY line in FIG. 4.

Shaku Mei (X Nose 1 Kui 9 To method) The manner in which the invention is carried out will be described below with reference to the drawings.

The formula below is the fraction of the exhaust gas that is treated with deuteron beams to form active species in the overburdened gas. percentage).

D. Size of electron beam irradiation chamber (diameter, m). This size is mainly determined by the accelerating voltage. The distance is set slightly wider than the maximum range of the electron beam. This size is even more exclusive. Varies depending on gas density and temperature. Therefore, the accelerating voltage is about 500KV or less. The distance is preferably about 2.0 m or less. Then, the electron beam accelerator This is because equipment costs for peripheral devices can be significantly reduced. .

■ Flow rate of exhaust gas in the electron irradiation chamber (m/sec). This value is generally It is preferable that the speed is about 30 m/sec or less. This value is about 30/sec If it is too large, the degree of pressure drop will increase undesirably. .

Q Amount of exhaust gas to be treated (m3/hour).

Table 2 below shows the relationship between accelerating voltage, electron beam irradiation chamber size, and exhaust gas flow rate. vinegar.

Blue Su 1000 Maximum 5.0 Maximum 30800 Maximum 3.7 Maximum 30500 Maximum 2-0 Maximum 30300 Maximum 1. 0 Maximum 30200 Maximum 0.6 Maximum 30 Figure 2 shows exhaust gas treatment for carrying out the exhaust gas treatment method of the present invention. The general structure of the device is shown, and FIG. 3 is a sectional view taken along the line XX in FIG. 2.

An electron beam irradiation chamber 8 for irradiating with an electron beam 7 from an electron beam accelerator 6 includes an exhaust gas 17 is located near the exhaust gas main duct 12 through which the exhaust gas flows. Electron beam irradiation from electron beam accelerator 6 The distance from the opening to the wall of the electron beam irradiation chamber 8 is slightly longer than the maximum range of the electron beam 7. Set to thick. One end of the electron beam irradiation chamber 8 communicates with the exhaust gas main duct 12; The other end is set in the exhaust gas main duct 12 via the suction pressure blower 9 and the pipe line 10. The dispersion device 113 is connected to the dispersion device 113. The dispersion device 13 is located in the center of the main duct 12. A concentric pipe 15 arranged concentrically with a plurality of radial pipes 14 extending in the radial direction from The radial pipe 14 and the concentric pipe 15 communicate with each other, and the pipe line 10 It also communicates with The radial pipe 14 and the concentric pipe 15 each have a flow of exhaust gas 17. A large number of small holes 16 are opened facing the downstream side. Suction pressure blower 9 and pipe line 10 are supply devices that form a set and supply air from the electron beam irradiation chamber 8 to the dispersion device 13. Configure.

Since the exhaust gas treatment equipment is arranged as described above, electron beams are transmitted from the exhaust gas main duct. The exhaust gas 18 sucked into the irradiation chamber 8 is irradiated with the electron beam 7 from the electron beam accelerator 6. Therefore, oxygen and water in the exhaust gas form active species such as O radicals and OH radicals.

The exhaust gas in which active species have been formed is passed through a pipe line 10 by a suction pressure blower 9. The exhaust gas is supplied to the dispersion device 13, and in the dispersion device 13, the exhaust gas is collected from the exhaust gas in the main duct 12. 17 and mixed therewith. As a result, O radicals and OH radicals Activated species such as alcohol act on harmful (gas) components such as Sow and NOl in exhaust gas 17, It changes to the form of salt (sulfuric acid, nitric acid, etc.). An appropriate amount of When ammonia is injected, the mist and the ammonia gas react with each other to form dust. Forms (ammonium sulfate, ammonium nitrate, etc.). This mist and dust is removed using an electrostatic precipitator. Collected by dust collectors (not shown) such as filters, activated carbon separators, etc. (all conventional) By doing this, harmful (gas) components such as S O2 and NOo are removed from the exhaust gas 17. It is possible to do so.

Figure 4 shows a schematic structure of another exhaust gas treatment device for carrying out the exhaust gas treatment method of the present invention. 5 is a sectional view taken along YY line in FIG. 4.

The electron beam irradiation chamber 21 is arranged near the exhaust gas main duct 23. Electron beam irradiation room 2 One end of 1 communicates with the exhaust gas main duct 23 via a pipe line 22, and the other end has a suction pressure of +1 It communicates with a dispersion device 27 via a feed blower 24, a pipe line 25 and an annular passage 26 ( Leak. The electron beam irradiation chamber 21 is equipped with an electron beam accelerator 19. Electron beam accelerator 19 The distance from the electron beam irradiation opening to the wall surface of the electron beam irradiation chamber 21 is the maximum distance of the electron beam 20. It is set to be slightly wider than the range.

The dispersion device 27 includes a plurality of fins 28 communicating with the annular passage 26 and fins 281. The blades 29 are arranged to face each other and rotate in the direction of the arrow 30. each The fin 28 has a large number of small holes 31 on the back side when viewed from the direction of the arrow, and the wings The vortex of the exhaust gas 32 generated by the rotation of the root 29 is irradiated with an electron beam and The exhaust gas delivered from the chamber 21 is uniformly dispersed and mixed with the exhaust gas 32. In the drawing ( The reference number 33 indicates the motor that rotates the blade 29, and the number 34 excludes the motor 33. A support member supported within the gas main duct 23 is shown.

In the above example, the blades 29 are rotated by the motor 33, but of course the blades 29 A drive unit, for example, a motor, is provided outside the exhaust gas main duct 23 to rotate the The rotational force from the The arrangement may also be such that the information is transmitted by

In the arrangement of the exhaust gas treatment device described above, the exhaust gas is sucked from the main duct 23 through the pipe line 22. A part of the drawn exhaust gas is irradiated with an electron beam 20 from an electron beam accelerator 19, and the example (the example shown in Figure 2) and total (similarly, oxygen and water in the exhaust gas are O radicals and OH radicals). Forms active species such as radicals. The exhaust gas in which active species have been formed is transferred to the dispersion device 2. 7 into the exhaust gas 32 in the exhaust gas main duct 23 and mix therewith.

As a result, the activated species act on the harmful (gas) components in the exhaust gas 32 and create mist and dust. form. Therefore, use dust collectors such as electrostatic precipitators, bag filters, and activated carbon separators. It can capture this mist and dust.

The structure of the exhaust gas treatment device shown in FIGS. 2 to 5 is an embodiment of the present invention. Note that these are not necessarily limited to these. In short, electronic The electron beam irradiation room for irradiation with the electron beam from the line accelerator was installed near the main exhaust gas duct. A part of the exhaust gas to be treated is introduced into the electron beam irradiation chamber, where an electric current is applied to the exhaust gas. Irradiation with a sub-beam to form active species such as O radicals and OH radicals: Active species inside The formed exhaust gas is fed into the exhaust gas main duct by a supply means; using a dispersion device. The exhaust gas introduced into the exhaust gas main duct is transferred to the exhaust gas flowing through the main duct. The (harmful) components in the exhaust gas are dispersed and mixed into a mist by the action of active species. and dust, and can be used in conventional methods such as electrostatic precipitators, bag filters, and activated carbon separators. Exhaust gas treatment equipment uses the trapping device of the dust collector to capture dust and mist. If so, what is the specific arrangement and structure of each part of the exhaust gas treatment equipment? It may be something that you have.

As described above, according to the present invention, a part of the exhaust gas is extracted and irradiated with an electron beam, and 1 Formation of active species in the gas that activates it [7, Next, the activated exhaust gas is It is mixed with the gas for processing purposes, thereby removing harmful (gas) components from the exhaust gas into mist or dust. It turns into a strike. Therefore, unlike the prior art, the entire waste residue is directly irradiated. There is no need to do so, and the amount of exhaust gas increases to a practical scale and the size of the exhaust gas duct increases. Even if it becomes larger in response to this, it will be equipped with a large number of electron accelerators! or increased the acceleration voltage. There is no need to do this. Therefore, equipment costs for the electron beam accelerator and peripheral equipment can be significantly reduced. It becomes possible. For example, in a traditional arrangement where an electron beam is applied directly to the waste In order to uniformly form active species in the exhaust gas, the exhaust gas duct size etc. In order to obtain sufficient electron beam energy, the acceleration voltage of the electron beam accelerator should be set to a high level, that is, 8 It was necessary to set it to 00KV to 1.0OOK V. In contrast, the present invention In some cases, an electron beam accelerator with an accelerating voltage of approximately 500 or less is sufficient; Equipment costs for speed machines and peripheral equipment can be significantly reduced.

Furthermore, the method and apparatus for treating exhaust gas by electron beam irradiation according to the present invention Harmful components of exhaust gas are removed by the action of chemical species (O radicals, OH radicals, etc.) The mist and dust are captured using conventional capture devices. Ru. Therefore, unlike the case where a wet absorption tower is used as described above, the present invention uses a wet absorption tower. When using the absorption liquid, it is necessary to treat the wastewater generated from the absorption liquid used in the process. In light, equipment costs and maintenance costs can be lowered.

Furthermore, since the present invention extracts a part of the exhaust gas and irradiates it with electron beams, it is not necessary to introduce it from the outside. Compared to the case where the air is irradiated with an electron beam, the exhaust gas irradiated with an electron beam is passed through the main duct. When mixed with flowing exhaust gas, the volume of the exhaust gas does not increase. That is, the present invention does not require a large capacity blower. However, the increase in total gas volume and desulfurization/desulfurization The slight decrease in efficiency of the glass is not a big problem, and it is possible to take in air and irradiate the electron beam. If this is preferred, air may be introduced instead of part of the exhaust gas.

The present invention will be explained in more detail below by way of examples, but the present invention is not limited to these examples. It is not something that will be done.

Example Exhaust gas (2,0 ppm) containing S02 (200 ppm) and NO, (180 ppm) 00Nm'/hour) to 70℃, then part of the exhaust gas is introduced into the irradiation chamber, and then Then, it was irradiated with an electron beam to form active species. Exhaust gas containing these active species The mixed exhaust gas is returned to the main exhaust gas duct and passed through the main duct to the electrostatic precipitator. where the generated dust was separated and the gas to be treated was released into the atmosphere. Experimental manipulation The test was carried out for about 150 hours.

Displays operating conditions, portion (proportion) of flue gas treated with electron beam and percentage of desulfurization and denitrification. Shown in 3.

Table 1゜ 100 20.000 1.000 10g 1.5 4.453 Jo, 600 800 108 1.5 3.215 3. 000 500 108 1.5 1. 74.2 840 300 108 1.5 0.91.3 260 200 108 1.5 0.50, 37 90 80 1570, 37 90 75 850.37 90 　　　　　　． 75 320.37 9 0 70 13V week ffl sex In the method and apparatus for treating exhaust gas by electron beam irradiation according to the present invention, Harmful (gas) components such as SO2 and NOl are removed using mist (sulfuric acid and/or nitric acid) or dust. After changing the form of mist (ammonium sulfate and/or ammonium sulfate), the generated mist and dust are transferred to a dust collector. etc. to capture it. Therefore, the method and apparatus of the present invention can be applied to fossil fuels such as heavy oil and coal. Boiler combustion exhaust gas from thermoelectric power generation plants that use fuel as fuel and sintering exhaust gas from steel plants It is suitable as a method and apparatus for treating gas.

Submission of translation of written amendment (Article 184-8 of the Patent Law) April 30, 1991 Toshi Ueki, Commissioner of the Japan Patent Office, 11, Patent application Display of pcT/JP88101101 , name of invention Method and device for treating exhaust gas by electron beam irradiation 3, patent applicant Address: Japan 144 11-1 Haneda Asahi-cho, Ota-ku, Tokyo Name: Co., Ltd. Company Zonko Seisakusho 4. Agent Address: Shin-Otemachi Building, 206-ku, 2-2-1 Otemachi, Chiyoda-ku, Tokyo 5. Date of submission of written amendment (1) Translation of the written amendment 1 supplementary copy of the original copy 1. (Correction) This is a method of treating the exhaust gas flowing in the main duct with electron beam irradiation. So, Based on the total volume of the exhaust gas to be treated, about 1.3 to about 15% by volume of the exhaust gas is A step of separating the recorder duct into the electron irradiation chamber. The proportion of exhaust gas separated is expressed as a percentage of the exhaust gas in the main duct (where D is Accelerating voltage below the diameter of the electron beam irradiation chamber, that is, approximately 200 kV to approximately 500 kV. 2.0 m or less, and ■ is the flow velocity of exhaust gas in the electron beam irradiation chamber, which is approximately 2.0 m or less. 30m/sec or less, and Q (m”/hour) is the processing flow rate in the main duct. This is the amount of exhaust gas. ): Defined by: Exhaust gas separated in the above separation step The part of the gas is irradiated in the irradiation chamber to form active species in the separated and irradiated exhaust gas. step: The separated and irradiated exhaust gas with the active species formed therein is The exhaust gas to be treated flowing through the main duct is mixed with the exhaust gas to be treated, thereby The harmful gas components in the exhaust gas flowing through the exhaust gas are converted into mist or by the action of the active species. converting into dust form, and Electron beam irradiation comprising the step of capturing the mist or dust using a dust collector. A method of treating exhaust gas flowing in the main duct.

2. (Correction) Equipment for treating exhaust gas flowing in the main duct with electron beam irradiation The location is An electron beam irradiation chamber 1 including one or more electron beam accelerators for irradiating the interior of the electron beam irradiation chamber. Approximately 1.3 to 15% by volume of the exhaust gas to be treated, based on the total volume of the exhaust gas to be treated. The exhaust gas is separated from the recording duct and the separated exhaust gas is supplied to the electron beam irradiation chamber. Then, the separated part of the exhaust gas is irradiated with an electron beam to form active species, and the The separated and irradiated exhaust gas in which the active species have been formed is treated as described above. Separation means for returning the flowing exhaust gas to the main duct, provided that the main duct The proportion of flue gas separated from the main duct is calculated as the percentage of flue gas flowing in the main duct ( In the formula, D is the diameter of the electron beam irradiation chamber, that is, the acceleration of about 200 kV to about 500 kV. The voltage is approximately 2.0 m or less, and ■ is the flow velocity of exhaust gas in the electron beam irradiation chamber. is about 30 m/sec or less, and Q (m!/hour) is the flow rate in the main duct mentioned above. This is the amount of exhaust gas that should be controlled. ): supplied from said separating means, The separated and irradiated exhaust gas with active species formed inside is uniformly distributed within the main duct. As a result, harmful gas components in the harmful gas flowing in the main duct are removed from the dispersion means for converting into a mist or dust form by the action of active species; Mist in which harmful gas components in the exhaust gas in the main duct have changed due to the action of the active species. Or inside the main duct by electron beam irradiation consisting of a dust collection means to capture dust. A device for treating exhaust gas flowing through.

3. (Cancellation) 4. (Cancellation) 5. (Cancellation) international search report international search report JP uo111] 1

Claims (2)

[Claims] 1. A method of treating exhaust gas by electron beam irradiation, in which a portion of the exhaust gas to be treated is forming active species in the irradiated exhaust gas by electron beam irradiation; The minute (ratio %) is calculated using the formula (π/4d2xVx3600/Q) x 100 (where D is the electron The diameter of the radiation chamber, that is, approximately 2.0 m or less for acceleration voltages of 500 kV or less. , V is the flow velocity of exhaust gas in the electron beam irradiation chamber, which is about 30 m/sec or less, Q (m3/hour) is the amount of exhaust gas to be treated. ) defined in; The exhaust gas in which active species have been formed is mixed with the exhaust gas to be treated, thereby Harmful (gas) components in the exhaust gas to be treated are misted by the action of the active species. or converting into the form of dust; and A method of treating exhaust gas comprising capturing the above-mentioned mist or dust using a dust collector. Law. 2. A device for treating exhaust gas by electron beam irradiation, from an electron beam accelerator. Electron beam irradiation chamber for irradiating a portion of the exhaust gas to be treated with electron beam; The exhaust gas is introduced into the injection chamber, where the exhaust gas is irradiated with an electron beam to form active species, and the inside In the exhaust gas main duct where the exhaust gas to be treated is flowing, the exhaust gas in which active species have been formed. equipment for supplying, provided that the said portion (%) of the exhaust gas is Formula (π/4d2xVx3600/Q) x 100 (where D is the diameter of the electron beam irradiation chamber , that is, for an accelerating voltage of 500 kV or less, it is approximately 2.0 m or less, and V is the electric current. The flow velocity of exhaust gas in the child beam irradiation chamber is approximately 30 m/sec or less, and Q (m3/hour) is the amount of exhaust gas to be treated. ); supplied from the above-mentioned supply device. A dispersion device for uniformly dispersing the exhaust gas into the main duct: and The harmful (gas) components in the exhaust gas in the main duct change due to the action of the active species described above. Exhaust gas by electron beam irradiation consists of a dust collector to capture mist or dust. equipment for processing