CN210186831U

CN210186831U - Poisonous waste gas treatment device

Info

Publication number: CN210186831U
Application number: CN201920554700.3U
Authority: CN
Inventors: Shouxiang Sheng; 盛守祥; Junting Feng; 冯俊亭; Chen Chen; 陈琛; Lianshun Feng; 冯连顺; Jian Ma; 马建
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-04-25
Filing date: 2019-04-25
Publication date: 2020-03-27
Anticipated expiration: 2029-04-25

Abstract

The utility model provides a poisonous waste gas's processing apparatus mainly contains wet-type electrostatic precipitator (1), one-level scrubbing tower (3), second grade scrubbing tower (6), tertiary scrubbing tower (9), gets into wet-type electrostatic precipitator system and detach fluorine-containing particulate matter in the waste gas, then gets into one to tertiary scrubbing tower, uses the acid-base gas in the chemical treatment waste gas in the tower, N0x, fluoride etc. tail gas discharge to reach standard.

Description

Poisonous waste gas treatment device

Technical Field

The utility model relates to a toxic waste gas's clean system especially relates to a toxic waste gas treatment device that TFT-LCD trade discharged.

Background

The poisonous waste gas in the TFT-LCD industry mainly comes from SiH used in the procedures of Chemical Vapor Deposition (CVD), Dry Etching (DE) and the like₄、NH₃、PH₃、NF₃、SF₆、N₂O、Cl₂And the special waste gas is partially consumed in the reaction in the process, a small amount of the waste gas is discharged in the form of tail gas, main pollutants are chlorine, ammonia, hydrogen chloride, fluoride, nitrogen oxide and the like, the complex waste gas components cannot be discharged after reaching the standard of the toxic waste gas actually by a single treatment mode or technology, and a set of special system is required to realize the discharge after reaching the standard of various toxic pollutants.

Disclosure of Invention

Be difficult to realize discharge to reach standard through single technique to complicated poisonous waste gas, the utility model provides a poisonous waste gas treatment device.

The utility model provides a poisonous waste gas treatment device, including wet-type electrostatic precipitator 1, NaOH storage tank 2, one-level scrubbing tower 3, H₂SO₄Storage tank 4, NaCLO₂The system comprises a storage tank 5, a secondary washing tower 6, a NaOH storage tank 7, a NaHS storage tank 8, a tertiary washing tower 9, a NaOH storage tank 10, a fan 11, a control system 12 and an exhaust gas online monitoring system 13.

And the NaOH storage tank 2 sprays NaOH into the wet electric dust collector 1 to be fully mixed and reacted with the toxic waste gas.

Said H₂SO₄Storage tank 4, NaCLO₂The storage tank 5 sprays H into the first-stage washing tower 3₂SO₄And NaCLO₂Mixing with toxic waste gas and reacting.

And the NaOH storage tank 7 and the NaHS storage tank 8 spray NaOH and NaHS into the secondary washing tower 6 to be fully mixed with the toxic waste gas for reaction.

The NaOH storage tank 10 sprays NaOH into the third-stage washing tower 9 to be fully mixed and reacted with the toxic waste gas, and the flow path of the toxic waste gas sequentially passes through the wet electric dust remover 1, the first-stage washing tower 3, the second-stage washing tower 6, the third-stage washing tower 9 and the fan 11 and finally reaches the standard to be discharged.

As further priority, wet-type electrostatic precipitator 1, one-level scrubbing tower 3, second grade scrubbing tower 6, tertiary scrubbing tower 9 export flue gas department all be equipped with the ORP value monitor, control system 12 adjusts chemical reagent's the volume of spraying in all kinds of storage tanks according to the ORP value.

As a further priority, the wet electric dust collector 1 of the present invention is used for removing fluorine-containing particles in the waste gas;

as a further priority, the NaOH storage tank 2 of the present invention is used for neutralizing acid gases in toxic waste gases;

as further priority, the utility model discloses an H₂SO₄Storage tank 4, NaCLO₂Tank 5 for oxidizing NO to NO in an acidic environment₂；

As further priority, the NaOH storage tank 7 and the NaHS storage tank 8 of the present invention are used for NO in the exhaust gas₂Reduction to N₂And salts;

as a further priority, the NaOH storage tank 10 of the present invention is used to neutralize residual CL in the exhaust gas₂And acid gases such as fluoride.

Drawings

FIG. 1 is a structural view of a toxic exhaust gas treating apparatus according to an embodiment.

Detailed Description

In order to make the utility model discloses purpose, technical scheme, control and advantage of implementation are more clear and definite, combine the utility model discloses the drawing in the embodiment is right the flow, technical scheme in the embodiment of the utility model are clear and definite, complete description. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

Aiming at toxic waste gas discharged by TFT-LCD industry, the toxic waste gas mainly comes from Chemical Vapor Deposition (CVD) and dry etchingSiH is used in the step (DE)₄、NH₃、PH₃、NF₃、SF₆、N₂O、Cl₂And the special waste gas is discharged in a tail gas form in a small amount except part of reaction consumption in the process, and main pollutants comprise chlorine, ammonia, hydrogen chloride, fluoride, nitrogen oxide and the like.

The specific implementation steps are as follows:

(1) the flow path of the toxic waste gas is that the toxic waste gas passes through a wet electric dust collector 1, a first-stage washing tower 3, a second-stage washing tower 6, a third-stage washing tower 9 and a fan 11 in sequence and finally reaches the standard to be discharged;

(2) the wet electric dust collector 1 is used for removing fluorine-containing particles in waste gas;

(3) the NaOH storage tank 2 is used for neutralizing acid gas in toxic waste gas;

(4) said H₂SO₄Storage tank 4, NaCLO₂Tank 5 for oxidizing NO to NO in an acidic environment₂；

(5) The NaOH storage tank 7 and the NaHS storage tank 8 are used for storing NO in the waste gas₂Reduction to N₂And salts;

(6) the NaOH storage tank 10 is used for neutralizing residual CL in waste gas₂Acid gases such as fluoride;

(7) the ORP value monitors are arranged at the outlet flue gas positions of the wet electric dust collector 1, the first-stage washing tower 3, the second-stage washing tower 6 and the third-stage washing tower 9, and the control system 12 adjusts the spraying amount of chemical reagents in various storage tanks according to the ORP value.

Through a whole set of system, particulate matters, acidic waste gas, N0x, fluoride and the like in the waste gas can be treated, and the treatment efficiency is over 95 percent.

Case 1

60000m toxic waste gas emission amount of certain TFT-LCD factory³/h。

(1) The waste gas passes through a wet electric precipitator in sequence, the input amount of NaOH is controlled by adjusting the wet water amount and adding NaOH and controlling the ORP value of the waste water after alkaline washing to be maintained at about 400mv, and the treatment process at the section adsorbs fluorine-containing particles in the waste gas and neutralizes acid gas in the waste gas;

(2) the waste gas after passing through the wet electric dust collector enters a first-stage washing tower, and H is added₂SO₄To ensure the acid environment of the waste gas in the tower, NaCLO₂Reacting NO in the flue gas into NO₂Setting ORP value at outlet of first-stage washing tower to be maintained at 400mv, and controlling H₂SO₄And NaCLO₂The dosage is controlled to maintain the ORP value at 400 mv;

(3) the waste gas after passing through the first-stage washing tower enters a second-stage washing tower, NaOH is added to ensure the alkaline environment of the waste gas in the tower, and NaHS is used for removing NO in the flue gas₂Reaction to N₂And salts, setting the ORP value at the outlet of the secondary washing tower to be maintained at 450mv, and controlling the ORP value to be maintained at 450mv by controlling the adding amount of NaOH and NaHS;

(4) the waste gas after passing through the second-stage washing tower enters a third-stage washing tower, NaOH is added to neutralize residual CL in the waste gas₂And the ORP value of the outlet of the three-stage washing tower is maintained at 450mv by setting the ORP value of the acid gases such as fluoride and the like, and the ORP value is maintained at 450mv by controlling the adding amount of NaOH.

After the flue gas passes through the three-stage washing tower, the treated exhaust gas is monitored, and the result shows that pollutants discharged by the exhaust gas all reach the national relevant standards.

Exhaust gas pollutant monitoring value (unit: mg/m 3)

Name of contaminant	1 month	2 month	3 month	4 month	Month 5
						Nitrogen oxides	52.9	68.0	59.9	32.1	65.2
Ammonia	1.7	16	1.3	0.0	0.0
						Hydrogen chloride	1.7	0.42	1.1	4.7	0.4
Fluoride compounds	2.3	1.6	3.3	1.5	3.1
						Chlorine gas	10.1	2.8	0.3	1.3	0.3

Claims

1. The toxic waste gas treatment device is characterized by comprising a wet-type electric dust collector (1), a NaOH storage tank (2), a primary washing tower (3) and H₂SO₄Storage tank (4) and NaCLO₂The system comprises a storage tank (5), a secondary washing tower (6), a NaOH storage tank (7), a NaHS storage tank (8), a tertiary washing tower (9), a NaOH storage tank (10), a fan (11), a control system (12) and an exhaust gas online monitoring system (13);

the NaOH storage tank (2) sprays NaOH into the wet electric dust collector (1) to be fully mixed and reacted with the toxic waste gas; said H₂SO₄Storage tank (4) and NaCLO₂The storage tank (5) sprays H into the first-stage washing tower (3)₂SO₄And NaCLO₂Fully mixing and reacting with toxic waste gas; the NaOH storage tank (7) and the NaHS storage tank (8) spray NaOH and NaHS into the secondary washing tower (6) to be fully mixed with toxic waste gas for reaction; the NaOH storage tank (10) sprays NaOH into the three-stage washing tower (9) to be fully mixed and reacted with the toxic waste gas;

the flow path of the toxic waste gas is that the toxic waste gas passes through a wet electric dust collector (1), a first-stage washing tower (3), a second-stage washing tower (6), a third-stage washing tower (9) and a fan (11) in sequence and finally reaches the standard to be discharged.

2. The toxic waste gas treatment device of claim 1, wherein the ORP value monitors are installed at the outlet flue gas of the wet electric dust collector (1), the first-stage scrubber tower (3), the second-stage scrubber tower (6) and the third-stage scrubber tower (9), and the control system (12) adjusts the spraying amount of the chemical agent in each type of storage tank according to the ORP value.

3. The toxic waste gas treatment device according to claim 1, wherein the wet electric dust collector (1) is used for removing fluorine-containing particles in waste gas; the NaOH storage tank (2) is used for neutralizing acid gas in toxic waste gas; said H₂SO₄Storage tank (4) and NaCLO₂Tank (5) for oxidizing NO to NO in an acidic environment₂(ii) a The NaOH storage tank (7) and the NaHS storage tank (8) are used for storing NO in the waste gas₂Reduction to N₂And salts; the NaOH storage tank (10) is used for neutralizing residual CL in the waste gas₂And a fluoride compound.