VOCs-containing waste gas purification process

Abstract

The invention relates to the technical field of waste gas treatment, and particularly provides a VOCs-containing waste gas purification process which comprises a first treatment device, a second treatment device, an adsorption device and a filtering device which are sequentially connected, and the purification effect of VOCs waste gas purification can be improved through the first treatment device, the second treatment device, the adsorption device and the filtering device which are sequentially arranged. A first treatment solution is arranged in the first treatment device, a second treatment solution is arranged in the second treatment device, the first treatment solution and the second treatment solution can be used for treating most VOCs in the waste gas, and the waste gas treatment effect is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of waste gas treatment, and specifically provides a purification process for waste gas containing VOCs. Background Art

[0002] In current production activities, many sewage treatment plants will generate a lot of organic VOCs waste gas. These VOCs waste gases often have a strong pungent odor. If directly discharged, it will cause environmental pollution. Currently, the treatment processes for VOCs waste gas include: condensation treatment method, oxidation treatment method, liquid adsorption method, activated carbon adsorption method, direct combustion method, catalytic combustion method, absorption method, etc. However, the purification effect of the above treatment methods on VOCs waste gas is relatively poor.

[0003] Therefore, a new technical solution is needed in this field to solve the above problems. Summary of the Invention

[0004] The present invention aims to solve the above technical problems, that is, to solve the problem of poor treatment effect of VOCs waste gas by the existing methods.

[0005] The present application provides a purification process for waste gas containing VOCs. The purification process for waste gas containing VOCs includes a first treatment device, a second treatment device, an adsorption device, and a filtration device connected in sequence;

[0006] The first treatment device and the second treatment device have the same structure, and both include a first device body having an accommodation space, and a first air inlet and a first air outlet respectively opened at the bottom and the top of the first device body; the first air outlet on the first device body is communicated with the first air inlet on the second device body;

[0007] A first treatment solution is provided in the first treatment device, and a second treatment solution is provided in the second treatment device;

[0008] The first treatment solution includes the following raw materials in parts by weight: 5 - 10 parts of transparent xanthan gum, 5 - 15 parts of water, 5 - 15 parts of ethanol, and 3 - 6 parts of Tween 80;

[0009] The second treatment solution includes the following raw materials in parts by weight: 2 - 3 parts of transparent xanthan gum, 5 - 15 parts of water, 5 - 15 parts of ethanol, and 1 - 2 parts of Tween 80.

[0010] In the preferred technical solution of the above purification process for waste gas containing VOCs, the adsorption device includes a first adsorption device;

[0011] The first adsorption device includes a second device body. The space inside the second device body is divided into a first air inlet area and a first air outlet area that communicate with each other. The second device body is provided with a second air inlet and a second air outlet. The second air inlet communicates with the first air inlet area, and the second air outlet communicates with the first air outlet area. The first air inlet area is arranged below the first air outlet area. The second air inlet communicates with the first air outlet on the second treatment device. Different graded packings are respectively arranged in the first air inlet area and the first air outlet area.

[0012] In the preferred technical solution of the above VOCs-containing waste gas purification process, the first packing in the first air inlet area includes particles of 20 - 50 cm, particles of 1 - 10 cm, particles of 1 - 10 mm, and particles of 0.1 - 1 mm, and the weight ratio is (0.5 - 1):(1 - 2):(1 - 2):(2 - 6).

[0013] In the preferred technical solution of the above VOCs-containing waste gas purification process, the first packing in the first air outlet area includes particles of 10 - 20 cm, particles of 1 - 10 cm, particles of 1 - 10 mm, particles of 0.1 - 1 mm, and 500 - 1000 μm, and the weight ratio is (1 - 1.5):(1 - 3):(2 - 5):(2 - 6):(2 - 3).

[0014] In the preferred technical solution of the above VOCs-containing waste gas purification process, the adsorption device further includes a second adsorption device. The second adsorption device includes a third device body. The space inside the third device body is divided into a second air inlet area and a second air outlet area that communicate with each other. The second device body is provided with a third air inlet and a third air outlet. The third air inlet communicates with the second air inlet area, and the third air outlet communicates with the second air outlet area. The second air inlet area is arranged below the second air outlet area. The second air outlet communicates with the third air inlet. Different graded second packings are respectively arranged in the second air inlet area and the second air outlet area.

[0015] In the preferred technical solution of the above VOCs-containing waste gas purification process, the second packing in the second air inlet area includes particles of 10 - 20 cm, particles of 5 - 10 cm, particles of 1 - 5 mm, particles of 0.1 - 1 mm, and 500 - 1000 μm, and the weight ratio is (0.5 - 1):(0.8 - 1.5):(2 - 5):(2 - 5):(2 - 4).

[0016] In the preferred technical solution of the above VOCs-containing waste gas purification process, the second packing in the second gas outlet area includes particles of 5-10 cm, 1-5 mm, 0.1-1 mm, and 500-1000 μm, and the weight ratio is (2-5):(3-10):(6-15):(6-15).

[0017] In the preferred technical solution of the above VOCs-containing waste gas purification process, a plurality of first filter layers and second filter layers are arranged at intervals in the filtering device.

[0018] In the preferred technical solution of the above VOCs-containing waste gas purification process, the first filter layer has a filtration efficiency of ≥85% for particulate matter with a particle size of ≥3.0 μm;

[0019] The second filter layer has a filtration efficiency of ≥70% for particulate matter with a particle size of ≥1.0 μm.

[0020] In the preferred technical solution of the above VOCs-containing waste gas purification process, an alkali washing spray device and an acid washing spray device are sequentially arranged between the second treatment device and the adsorption device.

[0021] The VOCs-containing waste gas purification process of the present invention can improve the purification effect of VOCs-containing waste gas by sequentially arranging a first treatment device, a second treatment device, an adsorption device, and a filtering device. Among them, by arranging a first treatment solution in the first treatment device and a second treatment solution in the second treatment device, the first treatment solution and the second treatment solution can remove most of the VOCs in the waste gas, improving the treatment effect of the waste gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings, in which:

[0023] Figure 1 is a flowchart of the VOCs-containing waste gas purification process of the present invention.

[0024] Reference Signs:

[0025] 1. First treatment device; 2. Second treatment device; 3. First adsorption device; 4. Second adsorption device; 5. Filtering device. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principle of the present invention and are not intended to limit the protection scope of the present invention.

[0027] It should be noted that in the description of the present invention, the terms indicating directions or positional relationships such as "upper", "lower", "left", "right", "front", "rear", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings. This is only for convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0028] In addition, it should also be noted that in the description of the present invention, unless otherwise clearly specified and defined, the terms "connection", "setting", "installation" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] Combined with Figure 1 introduce the purification process of VOCs-containing waste gas. Among them, Figure 1 is the flow chart of the purification process of VOCs-containing waste gas of the present invention.

[0030] Based on the problem of poor treatment effect of VOCs waste gas in the existing method pointed out in the background technology, the present application provides a purification process for VOCs-containing waste gas, which includes a first treatment device 1, a second treatment device 2, an adsorption device, and a filtration device 5 connected in sequence;

[0031] The first treatment device 1 and the second treatment device 2 have the same structure, and both include a first device body with a receiving space, and a first air inlet and a first air outlet respectively opened at the bottom and the top of the first device body; the first air outlet on the first device body is communicated with the first air inlet on the second device body;

[0032] A first treatment solution is provided in the first treatment device 1, and a second treatment solution is provided in the second treatment device 2;

[0033] The first treatment solution includes the following raw materials in parts by weight: 5-10 parts of transparent xanthan gum, 5-15 parts of water, 5-15 parts of ethanol, and 3-6 parts of Tween 80.

[0034] The second treatment solution includes the following raw materials in parts by weight: 2-3 parts of transparent xanthan gum, 5-15 parts of water, 5-15 parts of ethanol, and 1-2 parts of Tween 80.

[0035] The purification effect of VOCs waste gas purification can be improved by sequentially arranging the first treatment device 1, the second treatment device 2, the adsorption device, and the filtration device 5. Among them, by setting the first treatment solution in the first treatment device 1 and the second treatment solution in the second treatment device 2, most of the VOCs in the waste gas can be removed by the first treatment solution and the second treatment solution, improving the treatment effect of the waste gas.

[0036] In addition, transparent xanthan gum is a silicate polymer with high adsorption capacity. It can adsorb VOCs molecules onto the surface of xanthan gum through van der Waals forces and combine VOCs molecules with xanthan gum molecules through chemical bonding, thereby achieving the purpose of removing VOCs. In addition, by setting the concentration of transparent xanthan gum in the first treatment solution to be greater than the concentration of transparent xanthan gum in the second treatment solution, on the one hand, it is beneficial to remove VOCs, and on the other hand, it can also reduce costs.

[0037] It should be noted that one or more of Intalox saddles, Pall rings, and cascade rings are arranged in the first treatment device 1 and the second treatment device 2, which is beneficial to liquid distribution and increases gas channels, improving the purification effect on waste gas.

[0038] Preferably, the first treatment solution includes the following raw materials in parts by weight: 8 parts of transparent xanthan gum, 10 parts of water, 12 parts of ethanol, and 4 parts of Tween 80. The second treatment solution includes the following raw materials in parts by weight: 2 parts of transparent xanthan gum, 10 parts of water, 10 parts of ethanol, and 2 parts of Tween 80.

[0039] Preferably, the adsorption device includes a first adsorption device 3; the first adsorption device 3 includes a second device body, the space inside the second device body is divided into a first intake area and a first outlet area that communicate with each other, and a second intake port and a second outlet port are opened on the second device body, and the second intake port communicates with the first intake area, and the second outlet port communicates with the first outlet area; the first intake area is arranged below the first outlet area, and the second outlet port is arranged below the first area; the second intake port communicates with the first outlet port on the second treatment device 2, and different grades of first packing are arranged in the first intake area and the first outlet area respectively. By dividing the space inside the second device body into a first intake area and a first outlet area and arranging different grades of first packing in the first intake area and the first outlet area, on the one hand, it can remove the transparent xanthan gum carried in the gas, and on the other hand, it can also adsorb the residual harmful gases in the gas, such as benzene.

[0040] Among them, the first packing in the first air inlet area includes particles of 20 - 50 cm, 1 - 10 cm, 1 - 10 mm, and 0.1 - 1 mm, and the weight ratio is (0.5 - 1):(1 - 2):(1 - 2):(2 - 6). Preferably, the weight ratio is 0.7:1.5:2:4. By adopting the first packing with the above gradation, on the one hand, it is beneficial to remove VOCs, and on the other hand, it can also slow down the gas flow rate and improve the VOC purification effect.

[0041] The first packing in the first air outlet area includes particles of 10 - 20 cm, 1 - 10 cm, 1 - 10 mm, 0.1 - 1 mm, and 500 - 1000 μm, and the weight ratio is (1 - 1.5):(1 - 3):(2 - 5):(2 - 6):(2 - 3). Preferably, the weight ratio is 1:2:4:5:2. By adopting the first packing with the above gradation, on the one hand, it is beneficial to remove the residual VOCs in the gas, and on the other hand, it can also slow down the gas flow rate and improve the VOC purification effect.

[0042] Among them, the first packing in the first air inlet area and the first air outlet area can be the same or different, and they independently select activated carbon and / or zeolite. When the first packing is activated carbon and zeolite, there is no limitation on the activated carbon and zeolite, as long as it can remove harmful substances in the gas. For example, the mass ratio of activated carbon to zeolite is 1:1. In addition, this application has no limitation on the activated carbon and zeolite in the first packing with different gradations. For example, the mass ratio of activated carbon to zeolite in the particles of the same particle size is 1:1, that is, the mass ratio of activated carbon to zeolite in the particles of 20 - 50 cm is 1:1, the mass ratio of activated carbon to zeolite in the particles of 1 - 10 cm is 1:1, the mass ratio of activated carbon to zeolite in the particles of 1 - 10 mm is 1:1, and the mass ratio of activated carbon to zeolite in the particles of 0.1 - 1 mm is 1:1. The same is true for the first packing in the first air outlet area, which will not be elaborated here.

[0043] Preferably, the adsorption device further includes a second adsorption device 4. The second adsorption device 4 includes a third device body. The space inside the third device body is divided into a second intake area and a second outlet area that communicate with each other. A third intake port and a third outlet port are provided on the second device body. The third intake port communicates with the second intake area, and the third outlet port communicates with the second outlet area. The second intake area is arranged below the second outlet area. The second outlet port communicates with the third intake port. Different grades of second packing materials are provided in the second intake area and the second outlet area respectively. By dividing the space inside the third device body into a second intake area and a second outlet area and arranging different grades of second packing materials in the second intake area and the second outlet area, on the one hand, it can remove the residual transparent xanthan gum carried in the gas, and on the other hand, it can also adsorb the residual harmful gases in the gas, such as benzene and the like.

[0044] Among them, the second packing materials in the second intake area include particles of 10 - 20 cm, particles of 5 - 10 cm, particles of 1 - 5 mm, particles of 0.1 - 1 mm, and 500 - 1000 μm, and the weight ratio is (0.5 - 1):(0.8 - 1.5):(2 - 5):(2 - 5):(2 - 4). Preferably, the weight ratio is 0.8:1.2:3:4:3. By using the second packing materials with the above - mentioned grading, on the one hand, it is beneficial to remove the organic substances in the gas and improve the waste gas purification effect.

[0045] The second packing materials in the second outlet area include particles of 5 - 10 cm, particles of 1 - 5 mm, particles of 0.1 - 1 mm, and particles of 500 - 1000 μ, and the weight ratio is (2 - 5):(3 - 10):(6 - 15):(6 - 15). Preferably, the weight ratio is 4:7:12:13. By using the second packing materials with the above - mentioned grading, on the one hand, it is beneficial to remove the organic substances in the gas and improve the waste gas purification effect.

[0046] Among them, the second fillers in the second intake area and the second exhaust area can be the same or different, and independently selected from activated carbon and / or zeolite. When the first filler is activated carbon and zeolite, there is no limitation on the activated carbon and zeolite, as long as it can remove harmful substances in the gas. For example, the mass ratio of activated carbon to zeolite is 1:1. In addition, this application has no limitation on the activated carbon and zeolite in the second fillers of different gradations. For example, the mass ratio of activated carbon to zeolite in the particles of the same particle size is 1:1, that is, the mass ratio of activated carbon to zeolite in the particles of 10-20 cm is 1:1, the mass ratio of activated carbon to zeolite in the particles of 5-10 cm is 1:1, the mass ratio of activated carbon to zeolite in the particles of 1-5 mm is 1:1, the mass ratio of activated carbon to zeolite in the particles of 0.1-1 mm is 1:1, and the mass ratio of activated carbon to zeolite in the particles of 500-1000 μm is 1:1. The same is true for the second filler in the second exhaust area, which will not be elaborated here.

[0047] Preferably, a plurality of first filter layers and second filter layers are arranged at intervals in the filtering device 5. Among them, the first filter layer has a filtration efficiency of ≥85% for particulate matter with a particle size ≥3.0 μm; the second filter layer has a filtration efficiency of ≥70% for particulate matter with a particle size ≥1.0 μm. Through the above setting method, fine oil particulate matter in the waste gas can be removed.

[0048] Preferably, an alkali washing spray device and an acid washing spray device are sequentially arranged between the second treatment device 2 and the adsorption device. By arranging the alkali washing spray device, attachments such as organic matters, microorganisms, and oil stains in the gas can be removed, thereby improving the waste gas treatment effect. The acid washing spray device can convert some malodorous substances in the waste gas into odorless substances to achieve the purpose of deodorization.

[0049] Among them, the acidic washing liquid includes wood vinegar, citric acid, and Fenton reagent; the alkaline washing liquid is a sodium hydroxide solution. Preferably, the weight parts of the alkaline washing liquid are 5-10 parts of wood vinegar, 3-5 parts of citric acid, and 1-2 parts of Fenton reagent respectively; the mass concentration of sodium hydroxide in the sodium hydroxide solution is 2-5%. More preferably, the weight parts of the alkaline washing liquid are 8 parts of wood vinegar, 3 parts of citric acid, and 1.5 parts of Fenton reagent respectively; the mass concentration of sodium hydroxide in the sodium hydroxide solution is 3%. By limiting the components of the alkaline washing liquid and the acidic washing liquid, the waste gas treatment effect can be improved.

[0050] Taking a certain sewage treatment station as an example: the parameters of the waste gas passing through the purification process are: VOCs: 60 mg / m 3 , particulate matter: 120 mg / m 3 , the waste gas concentration (dimensionless): 1100. After being treated by the purification system of this embodiment, the emission tail gas parameters can reach: VOC ≤ 3 mg / m 3 , particulate matter ≤ 3 mg / m 3, Exhaust gas concentration (dimensionless): ≤ 150.

[0051] Those skilled in the art can understand that although some of the embodiments described herein include certain features included in other embodiments rather than other features, the combination of features of different embodiments means that it is within the scope of this application and forms different embodiments. For example, in the claims of this application, any one of the claimed embodiments can be used in any combination.

[0052] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A process for purifying waste gas containing VOCs, characterized in that: The VOCs-containing waste gas purification process includes a first treatment device, a second treatment device, an adsorption device and a filtering device connected in sequence; The first processing device has the same structure as the second processing device, and both include a first device body having an accommodating space, and a first air inlet and a first air outlet respectively disposed at the bottom and the top of the first device body; the first air outlet on the first device body is connected to the first air inlet on the second device body; A first treatment solution is disposed in the first treatment device, and a second treatment solution is disposed in the second treatment device; The first treatment solution includes the following raw materials in parts by weight: 5-10 parts of transparent xanthan gum, 5-15 parts of water, 5-15 parts of ethanol and 3-6 parts of Tween 80; The second treatment solution includes the following raw materials in parts by weight: 2-3 parts of transparent xanthan gum, 5-15 parts of water, 5-15 parts of ethanol and 1-2 parts of Tween 80.

2. The VOCs-containing waste gas purification process according to claim 1, characterized in that: The adsorption device includes a first adsorption device; The first adsorption device includes a second device body, the space inside the second device body is divided into a first air inlet area and a first air outlet area which are connected to each other, and a second air inlet and a second air outlet are provided on the second device body, and the second air inlet is connected to the first air inlet area, and the second air outlet is connected to the first air outlet area; the first air inlet area is arranged below the first air outlet area; the second air inlet is connected to the first air outlet on the second processing device, and the first air inlet area and the first air outlet area are respectively provided with fillers of different grades.

3. The VOCs-containing waste gas purification process according to claim 2, characterized in that: The first filler in the first air inlet area includes 20-50 cm particles, 1-10 cm particles, 1-10 mm particles, 0.1-1 mm particles, and the weight ratio is (0.5-1): (1-2): (1-2): (2-6).

4. The VOCs-containing waste gas purification process according to claim 2, characterized in that: The first filler in the first gas outlet area includes 10-20cm particles, 1-10cm particles, 1-10mm particles, 0.1-1mm particles and 500-1000μm, and the weight ratio is (1-1.5):(1-3):(2-5):(2-6):(2-3).

5. The VOCs-containing waste gas purification process according to claim 1, characterized in that: The adsorption device also includes a second adsorption device, which includes a third device body, wherein the space inside the third device body is divided into a second air inlet area and a second air outlet area which are connected to each other, and a third air inlet and a third air outlet are provided on the second device body, and the third air inlet is connected to the second air inlet area, and the third air outlet is connected to the second air outlet area; the second air inlet area is arranged below the second air outlet area; the second air outlet is connected to the third air inlet; and the second air inlet area and the second air outlet area are respectively provided with second fillers of different grades.

6. The VOCs-containing waste gas purification process according to claim 5, characterized in that: The second filler in the second air inlet area includes 10-20 cm particles, 5-10 cm particles, 1-5 mm particles, 0.1-1 mm particles and 500-1000 μm, and the weight ratio is (0.5-1): (0.8-1.5): (2-5): (2-5): (2-4).

7. The VOCs-containing waste gas purification process according to claim 5, characterized in that: The second filler in the second gas outlet area includes 5-10 cm particles, 1-5 mm particles, 0.1-1 mm particles and 500-1000 μ particles, and the weight ratio is (2-5): (3-10): (6-15): (6-15).

8. The VOCs-containing waste gas purification process according to claim 1, characterized in that: The filter device is provided with a plurality of first filter layers and second filter layers which are arranged at intervals.

9. The VOCs-containing waste gas purification process according to claim 8, characterized in that: The first filter layer has a filtration efficiency of ≥85% for particles with a diameter of ≥3.0μm; The second filter layer has a filtration efficiency of ≥70% for particles with a diameter ≥1.0μm.

10. The VOCs-containing waste gas purification process according to claim 1, characterized in that: An alkali washing spray device and an acid washing spray device are sequentially arranged between the second treatment device and the adsorption device.

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