Device for preparing electronic-grade hydrogen sulfide from thiophene production waste gas

Abstract

The utility model belongs to the technical field of separation devices, and particularly relates to a device for preparing electronic-grade hydrogen sulfide from thiophene production waste gas, which comprises a gas inlet pipe, the end, away from the organic purification washing tower, of the first air outlet pipe is connected with an inorganic purification washing tower, the top of the inorganic purification washing tower is provided with a second air outlet pipe, and the end, away from the inorganic purification washing tower, of the second air outlet pipe is sequentially connected with a demister, a molecular sieve adsorber, a molding press, a condenser and a hydrogen sulfide liquefier. One end, far away from the hydrogen sulfide liquefier, of the liquid discharge pipe is connected with a rectifying tower; according to the device, the thiophene production waste gas can be purified and converted into electronic-grade hydrogen sulfide, so that the purification treatment cost of the thiophene production waste gas is reduced, and the raw material input in the production process of the electronic-grade hydrogen sulfide is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of separation devices, and in particular relates to a device for preparing electronic-grade hydrogen sulfide from waste gas produced by thiophene production. Background Art

[0002] Electronic-grade hydrogen sulfide plays an indispensable role in the electronics industry. In semiconductor manufacturing, electronic-grade hydrogen sulfide is often used in the doping process of N-type semiconductors. In the CVD process, electronic-grade hydrogen sulfide, as an important sulfur source gas, is widely used in the preparation of various sulfide thin film materials. When preparing gas sensors, the specific chemical reaction or physical adsorption between electronic-grade hydrogen sulfide and the sensitive material of the sensor is often used to achieve high-sensitivity detection of specific gases.

[0003] In the thiophene production process, a large amount of hydrogen sulfide gas is generated. Theoretically, for every ton of thiophene product produced, 0.4 to 0.7 tons of hydrogen sulfide gas will be generated. However, these hydrogen sulfide gases will not exist alone, but will be mixed with other waste gas components generated in the thiophene production process to form thiophene production waste gas. For thiophene production companies, it is necessary to invest a lot of money to treat thiophene production waste gas. If the thiophene production waste gas can be converted and utilized, it can not only save the cost of thiophene production waste gas treatment, but also provide raw materials for the preparation of electronic grade hydrogen sulfide. However, the composition of thiophene production waste gas is complex, and it also contains CO 2 , CO, S, tar, ash and other impurities, and cannot be used directly as chemical raw materials. It can only be used after being purified to meet the quality standards. Utility Model Content

[0004] The utility model aims to provide a device for preparing electronic grade hydrogen sulfide from thiophene production waste gas, which can purify the thiophene production waste gas and convert it into electronic grade hydrogen sulfide, thereby reducing the purification cost of the thiophene production waste gas and reducing the raw material input in the production process of electronic grade hydrogen sulfide.

[0005] To achieve the above purpose, the technical solution of the utility model is:

[0006] The device for preparing electronic grade hydrogen sulfide from thiophene production waste gas comprises an air inlet pipe, one end of the air inlet pipe is connected to an organic purification washing tower, the top of the organic purification washing tower is provided with an air outlet pipe 1, the end of the air outlet pipe 1 away from the organic purification washing tower is connected to an inorganic purification washing tower, the top of the inorganic purification washing tower is provided with an air outlet pipe 2, the end of the air outlet pipe 2 away from the inorganic purification washing tower is sequentially connected to a demister, a molecular sieve adsorber, a molding machine, a condenser and a hydrogen sulfide liquefier, a drain pipe is provided at the bottom of the hydrogen sulfide liquefier, the end of the drain pipe away from the hydrogen sulfide liquefier is connected to a distillation tower, and the top of the distillation tower is provided with an air outlet pipe 3.

[0007] in:

[0008] The organic purification washing tower is provided with a circulation pipeline 1 on the side away from the air inlet pipe.

[0009] One end of the circulation pipeline is connected to the lower part of the side wall of the organic purification washing tower, and the other end of the circulation pipeline passes through the upper part of the side wall of the organic purification washing tower and is connected to a spray head.

[0010] The circulating pipeline is provided with a circulating pump.

[0011] A second circulation pipeline is provided on the side of the inorganic purification washing tower away from the organic purification washing tower.

[0012] One end of the circulating pipeline 2 is connected to the lower part of the side wall of the inorganic purification washing tower, and the other end of the circulating pipeline 2 passes through the upper part of the side wall of the inorganic purification washing tower and is connected to the second spray head.

[0013] The second circulation pipeline is provided with a second circulation pump.

[0014] An exhaust pipe is arranged on the top of the hydrogen sulfide liquefier.

[0015] One end of the exhaust pipe away from the hydrogen sulfide liquefier is connected with a gas processing unit.

[0016] One end of the liquid discharge pipe away from the hydrogen sulfide liquefier is connected to the lower part of the side wall of the distillation tower.

[0017] The beneficial effects of the utility model are:

[0018] The organic purification washing tower and the inorganic purification washing tower can remove impurities from the thiophene production waste gas and continuously purify the thiophene production waste gas; the demister and the molecular sieve adsorber can reduce the moisture content in the thiophene production waste gas; the molding machine, the condenser and the hydrogen sulfide liquefier can liquefy the hydrogen sulfide in the thiophene production waste gas; the distillation tower can distill and purify the liquefied hydrogen sulfide; the device can extract electronic grade hydrogen sulfide from the thiophene production waste gas, reducing the cost of thiophene production waste gas treatment, and at the same time providing a stable and relatively cheap source of raw materials for the production of electronic grade hydrogen sulfide, reducing the raw material input in the production process of electronic grade hydrogen sulfide. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the utility model;

[0020] In the figure:

[0021] 1. Inlet pipe; 2. Organic purification washing tower; 3. Outlet pipe one; 4. Inorganic purification washing tower; 5. Outlet pipe two; 6. Defogger; 7. Molecular sieve adsorber; 8. Molding machine; 9. Condenser; 10. Hydrogen sulfide liquefier; 11. Distillation tower; 12. Outlet pipe three; 13. Circulation pipeline one; 14. Spray head one; 15. Circulation pump one; 16. Circulation pipeline two; 17. Spray head two; 18. Circulation pump two; 19. Exhaust pipe; 20. Gas treatment unit; 21. Drain pipe. DETAILED DESCRIPTION

[0022] The utility model is described and illustrated in detail below in conjunction with the accompanying drawings.

[0023] Example 1

[0024] like Figure 1 As shown, the device for preparing electronic grade hydrogen sulfide from thiophene production waste gas comprises an air inlet pipe 1, one end of the air inlet pipe 1 is connected to an organic purification washing tower 2, the top of the organic purification washing tower 2 is provided with an air outlet pipe 3, the end of the air outlet pipe 3 away from the organic purification washing tower 2 is connected to an inorganic purification washing tower 4, the top of the inorganic purification washing tower 4 is provided with an air outlet pipe 2 5, the end of the air outlet pipe 2 5 away from the inorganic purification washing tower 4 is sequentially connected to a demister 6, a molecular sieve adsorber 7, a molding machine 8, a condenser 9 and a hydrogen sulfide liquefier 10, the bottom of the hydrogen sulfide liquefier 10 is provided with a drain pipe 21, the end of the drain pipe 21 away from the hydrogen sulfide liquefier 10 is connected to a distillation tower 11, and the top of the distillation tower 11 is provided with an air outlet pipe 3 12.

[0025] The organic purification washing tower 2 and the inorganic purification washing tower 4 can remove impurities in the thiophene production waste gas and continuously purify the thiophene production waste gas; the demister 6 and the molecular sieve adsorber 7 can reduce the moisture content in the thiophene production waste gas; the molding machine 8, the condenser 9 and the hydrogen sulfide liquefier 10 can liquefy the hydrogen sulfide in the thiophene production waste gas; the distillation tower 11 can distill and purify the liquefied hydrogen sulfide; the device can extract electronic grade hydrogen sulfide from the thiophene production waste gas, reducing the cost of thiophene production waste gas treatment, and at the same time providing a stable and relatively cheap source of raw materials for the production of electronic grade hydrogen sulfide, reducing the raw material input in the production process of electronic grade hydrogen sulfide.

[0026] A circulation pipeline 13 is provided on the side of the organic purification washing tower 2 away from the air inlet pipe 1 .

[0027] One end of the circulation pipeline 13 is connected to the lower part of the side wall of the organic purification washing tower 2, and the other end of the circulation pipeline 13 passes through the upper part of the side wall of the organic purification washing tower 2 and is connected to a spray head 14.

[0028] A circulation pump 15 is provided on the circulation pipeline 13.

[0029] An organic washing liquid is arranged inside the organic purification washing tower 2, and the organic washing liquid is difluoromethane or trifluoromethane. The organic washing liquid can remove impurities such as S, tar and ash in the thiophene production waste gas; the circulation pipeline 13 can make the organic washing liquid in the organic purification washing tower 2 circulate continuously, thereby improving the utilization rate of the organic washing liquid; the spray head 14 can increase the contact area between the organic washing liquid and the thiophene production waste gas, thereby ensuring that the impurities in the thiophene production waste gas are fully treated.

[0030] A circulation pipeline 2 16 is provided on the side of the inorganic purification washing tower 4 away from the organic purification washing tower 2 .

[0031] One end of the second circulation pipeline 16 is connected to the lower part of the side wall of the inorganic purification washing tower 4 , and the other end of the second circulation pipeline 16 passes through the upper part of the side wall of the inorganic purification washing tower 4 and is connected to the second spray head 17 .

[0032] The circulation pipeline 16 is provided with a circulation pump 18 .

[0033] Inorganic cleaning tower 4 is provided with an inorganic cleaning liquid, which is a NaHS solution or a Na 2 S solution or NaCl solution can remove the residual organic impurities in the thiophene production waste gas through the inorganic washing liquid; the circulation pipeline 16 can make the inorganic washing liquid in the inorganic purification washing tower 4 circulate continuously, thereby improving the utilization rate of the inorganic washing liquid; the spray head 17 can increase the contact area between the inorganic washing liquid and the thiophene production waste gas, ensuring that the residual organic impurities in the thiophene production waste gas are fully treated.

[0034] An exhaust pipe 19 is provided at the top of the hydrogen sulfide liquefier 10 .

[0035] The end of the exhaust pipe 19 away from the hydrogen sulfide liquefier 10 is connected to a gas processing unit 20. The exhaust pipe 19 can remove the CO in the hydrogen sulfide liquefier 10. 2 and CO and other gases are discharged; the gas processing unit 20 can further process the gas discharged from the hydrogen sulfide liquefier 10.

[0036] One end of the liquid discharge pipe 21 away from the hydrogen sulfide liquefier 10 is connected to the lower part of the side wall of the distillation tower 11 .

[0037] Working process and principle:

[0038] The thiophene production waste gas enters the organic purification washing tower 2 through the air inlet pipe 1. The organic purification washing tower 2 contains an organic washing liquid. Under the low temperature environment of -15~-45℃, the organic washing liquid is fully in contact with the thiophene production waste gas, thereby removing impurities such as tar, ash and S in the thiophene production waste gas.

[0039] After organic purification and washing, the thiophene production waste gas enters the inorganic purification washing tower 4 through the outlet pipe 3. The inorganic purification washing tower 4 contains inorganic washing liquid. Under the low temperature environment of -15~-25℃, the inorganic washing liquid is fully in contact with the thiophene production waste gas, thereby removing the residual organic impurities in the thiophene production waste gas.

[0040] The purified thiophene production waste gas enters the demister 6 from the inorganic purification washing tower 4 to remove most of the water entrained in the thiophene production waste gas, and then enters the molecular sieve adsorber 7. The molecular sieve adsorber 7 is provided with a 5A molecular sieve inside, and the moisture content in the thiophene production waste gas is reduced to 5ppm through adsorption.

[0041] The thiophene production waste gas after demisting and dehydration enters the molding machine 8, where it is compressed to a pressure of 1.8 MPa, and then enters the condenser 9 to cool the compressed thiophene production waste gas at a temperature of -25°C.

[0042] The compressed and pre-cooled thiophene production waste gas enters the hydrogen sulfide liquefier 10, where the hydrogen sulfide in the thiophene production waste gas is liquefied, while some impurity gases such as CO 2 , CO is discharged through the exhaust pipe 19 and sent to the gas treatment unit 20 for further treatment.

[0043] The liquefied hydrogen sulfide enters the distillation tower 11 through the discharge pipe 21. The bottom temperature of the distillation tower 11 is 25-35°C, the bottom pressure is 2-2.5 kPa, the top temperature is -5-0°C, and the top pressure is 0.9-1.0 MPa. The liquefied hydrogen sulfide is purified in the distillation tower 11 to obtain hydrogen sulfide gas, which is discharged from the distillation tower 11 through the outlet pipe 3 12. The purity of the hydrogen sulfide gas is above 99.99%, and the water content is less than 0.5 ppm, which meets the electronic grade hydrogen sulfide standard.

Claims

1. A device for preparing electronic grade hydrogen sulfide from waste gas produced by thiophene production, comprising an air inlet pipe (1), characterized in that: An organic purification washing tower (2) is connected to one end of an air inlet pipe (1), an air outlet pipe 1 (3) is arranged on the top of the organic purification washing tower (2), an end of the air outlet pipe 1 (3) away from the organic purification washing tower (2) is connected to an inorganic purification washing tower (4), an air outlet pipe 2 (5) is arranged on the top of the inorganic purification washing tower (4), an end of the air outlet pipe 2 (5) away from the inorganic purification washing tower (4) is connected in sequence to a demister (6), a molecular sieve adsorber (7), a molding machine (8), a condenser (9) and a hydrogen sulfide liquefier (10), a liquid discharge pipe (21) is arranged at the bottom of the hydrogen sulfide liquefier (10), an end of the liquid discharge pipe (21) away from the hydrogen sulfide liquefier (10) is connected to a distillation tower (11), and an air outlet pipe 3 (12) is arranged on the top of the distillation tower (11).

2. The device for preparing electronic grade hydrogen sulfide from thiophene production waste gas according to claim 1, characterized in that: A circulation pipeline 1 (13) is provided on the side of the organic purification washing tower (2) away from the air inlet pipe (1).

3. The device for preparing electronic grade hydrogen sulfide from thiophene production waste gas according to claim 2, characterized in that: One end of the circulation pipeline 1 (13) is connected to the lower part of the side wall of the organic purification washing tower (2), and the other end of the circulation pipeline 1 (13) passes through the upper part of the side wall of the organic purification washing tower (2) and is connected to a spray head 1 (14).

4. The device for preparing electronic grade hydrogen sulfide from thiophene production waste gas according to claim 3, characterized in that: A circulation pump 1 (15) is provided on the circulation pipeline 1 (13).

5. The device for preparing electronic grade hydrogen sulfide from thiophene production waste gas according to claim 1, characterized in that: A second circulation pipeline (16) is provided on the side of the inorganic purification washing tower (4) away from the organic purification washing tower (2).

6. The device for preparing electronic grade hydrogen sulfide from thiophene production waste gas according to claim 5, characterized in that: One end of the second circulation pipeline (16) is connected to the lower part of the side wall of the inorganic purification washing tower (4), and the other end of the second circulation pipeline (16) passes through the upper part of the side wall of the inorganic purification washing tower (4) and is connected to the second spray head (17).

7. The device for preparing electronic grade hydrogen sulfide from thiophene production waste gas according to claim 6, characterized in that: A second circulation pump (18) is provided on the second circulation pipeline (16).

8. The device for preparing electronic grade hydrogen sulfide from thiophene production waste gas according to claim 1, characterized in that: An exhaust pipe (19) is provided at the top of the hydrogen sulfide liquefier (10).

9. The device for preparing electronic grade hydrogen sulfide from thiophene production waste gas according to claim 8, characterized in that: One end of the exhaust pipe (19) away from the hydrogen sulfide liquefier (10) is connected to a gas processing unit (20).

10. The device for preparing electronic grade hydrogen sulfide from thiophene production waste gas according to claim 1, characterized in that: One end of the liquid discharge pipe (21) away from the hydrogen sulfide liquefier (10) is connected to the lower part of the side wall of the distillation tower (11).

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