Chlorosilane tail gas absorption device

Abstract

The utility model discloses a chlorosilane tail gas absorption device which comprises a first-stage absorption tower and a second-stage absorption tower, a first communicating pipe and a second communicating pipe are arranged on the lower portions of the two absorption towers in parallel, stop valves are arranged at the two ends of the first communicating pipe and the two ends of the second communicating pipe, and the first communicating pipe and the second communicating pipe are connected with high-pressure water pipelines. A first high-pressure water valve is arranged between the first communicating pipe and the high-pressure water pipeline, and a second high-pressure water valve is arranged between the second communicating pipe and the high-pressure water pipeline. Compared with the prior art, the high-pressure water flushing control is added on the communicating pipe between the two absorption towers, so that hydrolysates generated by reaction of chlorosilane and water can be flushed away, the hydrolysates are prevented from being attached to the pipeline wall, and the pipeline blockage is reduced. Meanwhile, the two communicating pipes are arranged between the two tail gas absorption towers in parallel, so that the other communicating pipe can be switched to be used at any time after the communicating pipe is blocked in use, and the normal work of the absorption towers is not influenced.

Description

Technical Field

[0001] The utility model relates to the technical field of chlorosilane tail gas treatment, in particular to a chlorosilane tail gas absorption device. Background Art

[0002] Chlorosilane tail gas absorption tower is mostly used to treat waste gas in chemical production system, so as to ensure the safe production of enterprises and the compliance of tail gas emission standards. Chlorosilane tail gas absorption tower uses the acid-base neutralization principle, see the attached Figure 1 The eluent in the absorption tower is a strongly alkaline liquid. Driven by the eluent circulation pump, the eluent is sprayed from the absorption tower to the bottom through the spray head. Chlorosilane tail gas enters the absorption tower from the top, where the alkaline eluent and the chlorosilane tail gas are neutralized, achieving full reaction and absorption. The neutralized liquid flows into the water pool below the absorption tower under the action of gravity. The neutralized gas flows from the primary absorption tower through a connecting pipeline into the secondary absorption tower for further acid-base neutralization treatment before being discharged into the atmosphere through the water seal tank at the top of the secondary absorption tower.

[0003] When treating chlorosilane tail gas, the hydrolysis products produced by the hydrolysis of chlorosilane often clog the connecting pipes, causing the tail gas pressure to rise and the absorber to be unable to operate normally. Therefore, it is particularly important to ensure that the connecting pipes between the cascaded chlorosilane absorbers are unobstructed. Utility Model Content

[0004] In order to solve the above technical problems, the utility model provides a chlorosilane tail gas absorption device, which adds a high-pressure water pipeline to the connecting pipeline, which can flush out the hydrolyzate produced by the reaction of chlorosilane and water, prevent the hydrolyzate from adhering to the pipeline wall, and delay the blockage of the connecting pipeline.

[0005] In order to achieve this technical purpose, the utility model adopts the following scheme:

[0006] A chlorosilane tail gas absorption device comprises a primary absorption tower and a secondary absorption tower, wherein a first connecting pipe and a second connecting pipe are arranged in parallel at the lower parts of the primary absorption tower and the secondary absorption tower, a first shut-off valve and a third shut-off valve are respectively provided at one end of the first connecting pipe and the second connecting pipe close to the primary absorption tower, a second shut-off valve and a fourth shut-off valve are respectively provided at one end of the first connecting pipe and the second connecting pipe close to the secondary absorption tower, both the first connecting pipe and the second connecting pipe are connected to a high-pressure water pipeline, a first high-pressure water valve is provided between the first connecting pipe and the high-pressure water pipeline, and a second high-pressure water valve is provided between the second connecting pipe and the high-pressure water pipeline.

[0007] Compared with the prior art, the beneficial effects of the present invention are:

[0008] By adding high-pressure water flushing control on the connecting pipe between two tail gas absorption towers, the hydrolyzate generated by the reaction of chlorosilane and water can be flushed away, preventing the hydrolyzate from adhering to the pipe wall and reducing the risk of pipeline blockage. At the same time, two parallel connecting pipes are arranged between the two tail gas absorption towers, so that after the connecting pipe in use is blocked, it can be switched to the other connecting pipe at any time without affecting the normal operation of the absorption tower.

[0009] Furthermore, an exhaust gas pipeline is connected to the top of the first-stage absorption tower, and a nitrogen gas pipeline is connected to the upper part of the first-stage absorption tower to prevent the generation of hydrolyzate from blocking the top of the tail gas absorption tower and to enable the replacement and purging of the tail gas absorption tower. Spraying devices are arranged in the first-stage absorption tower and the second-stage absorption tower, and the spraying devices are connected to an alkaline water pipeline. A water tank is arranged at the bottom of the first-stage absorption tower and the second-stage absorption tower, a water seal tank is connected to the top of the second-stage absorption tower, an exhaust pipe is arranged on the water seal tank, and a remote pressure gauge is arranged on the exhaust gas pipeline.

[0010] The chlorosilane tail gas enters from the upper part of the first-stage absorption tower. In the first-stage absorption tower, its alkaline washing liquid reacts with the chlorosilane tail gas to achieve acid-base neutralization for full reaction and absorption. The liquid after acid-base neutralization flows into the water tank at the bottom of the absorption tower under the action of gravity. The gas after acid-base neutralization enters the second-stage absorption tower through the connecting pipeline from the first-stage absorption tower for further acid-base neutralization treatment, and then is discharged into the atmosphere through the water seal tank at the top of the second-stage absorption tower. The remote pressure gauge on the exhaust gas pipeline detects the pressure inside the absorption tower, and judges the blockage situation of the connecting pipeline according to the pressure level inside the absorption tower. When absorbing the tail gas, the nitrogen gas pipeline is opened to prevent the generation of hydrolyzate from blocking the pipeline or the upper part of the absorption tower at the top of the tail gas absorption tower. According to the actual situation, after the chlorosilane tail gas is treated, the tail gas absorption device can be purged through the nitrogen gas pipeline. Description of the Drawings

[0011] Figure 1 is the original chlorosilane tail gas absorption device;

[0012] Figure 2 is the chlorosilane tail gas absorption device of the present utility model;

[0013] In the figure, the labels are: 1, the first-stage absorption tower; 2, the second-stage absorption tower; 3, the water seal tank; 301, the exhaust pipe; 4, the water tank; 5, the first connecting pipe; 501, the first cut-off valve; 502, the second cut-off valve; 6, the second connecting pipe; 601, the third cut-off valve; 602, the fourth cut-off valve; 7, the high-pressure water pipeline; 701, the first high-pressure water valve; 702, the second high-pressure water valve; 8, the exhaust gas pipeline; 9, the alkaline water pipeline; 10, the nitrogen gas pipeline. Detailed Embodiments

[0014] To fully understand the purpose, features and effects of the present utility model, the present utility model will be described in detail through the following specific embodiments, but the present utility model is not limited thereto.

[0015] Refer to Figure 2 , the present utility model provides a technical solution: a chlorosilane tail gas absorption device, including a primary absorption tower 1 and a secondary absorption tower 2. The top of the primary absorption tower 1 is connected to an exhaust gas pipeline 8, and a remote pressure gauge is provided on the exhaust gas pipeline 8. The upper part of the primary absorption tower 1 is connected to a nitrogen pipeline 10. Spraying devices are provided in the primary absorption tower 1 and the secondary absorption tower 2, and the spraying devices are connected to an alkaline water pipeline 9. The lower parts of the primary absorption tower 1 and the secondary absorption tower 2 are provided with a first connecting pipe 5 and a second connecting pipe 6 in parallel. First cut-off valves 501 and third cut-off valves 601 are respectively provided at one ends of the first connecting pipe 5 and the second connecting pipe 6 close to the primary absorption tower 1. Second cut-off valves 502 and fourth cut-off valves 602 are respectively provided at one ends of the first connecting pipe 5 and the second connecting pipe 6 close to the secondary absorption tower 2. Both the first connecting pipe 5 and the second connecting pipe 6 are connected to a high-pressure water pipeline 7. A first high-pressure water valve 701 is provided between the first connecting pipe 5 and the high-pressure water pipeline 7, and a second high-pressure water valve 702 is provided between the second connecting pipe 6 and the high-pressure water pipeline 7. High-pressure water can wash away the hydrolyzed substances scaling the pipeline wall, and the flushing time and the high-pressure water pressure can be adjusted according to actual conditions. The bottoms of the primary absorption tower 1 and the secondary absorption tower 2 are provided with a tower bottom water pool 4. The top of the secondary absorption tower 2 is connected to a water seal tank 3, and an air release pipeline 301 is provided on the water seal tank 3.

[0016] The chlorosilane tail gas enters from the top of the primary absorption tower 1, and in the primary absorption tower 1, its alkaline rinsing liquid and the chlorosilane tail gas are subjected to acid-base neutralization to achieve full reaction absorption. Open the nitrogen pipeline 10 to prevent the generation of hydrolyzed substances at the top of the tail gas absorption tower from blocking the pipeline or the upper part of the absorption tower. The liquid after acid-base neutralization flows into the tower bottom water pool 4 of the absorption tower under the action of gravity. The gas after acid-base neutralization enters the secondary absorption tower 2 from the primary absorption tower 1 through the first connecting pipeline 5 for further acid-base neutralization treatment, and then is discharged into the atmosphere through the water seal tank 3 at the top of the secondary absorption tower 2. The remote pressure gauge detects the pressure inside the absorption tower, and the blockage condition of the connecting pipeline can be judged according to the pressure inside the absorption tower. When the pressure inside the absorption tower rises, open the first high-pressure water valve 701 on the high-pressure water pipeline 7 connected to the first connecting pipe 5 to wash the first connecting pipe 5 and wash away the hydrolyzed substances generated by the reaction of chlorosilane and water, avoiding the attachment of hydrolyzed substances to the pipeline wall and reducing the blockage of the pipeline. When the remote pressure is high and the high-pressure water flushing is ineffective, it indicates that the first connecting pipe 5 is blocked. Open the third cut-off valve 601 and the fourth cut-off valve 602, and at the same time close the first cut-off valve 501 and the second cut-off valve 502, which does not affect the normal operation of the absorption tower and provides guarantee for the safe and stable operation of the production system.

[0017] After the treatment of the chlorosilane tail gas, the tail gas absorption device can be purged through the nitrogen gas pipeline 10.

[0018] Finally, it should be noted that the above-listed are only the preferred embodiments of the present utility model. Of course, those skilled in the art can make changes and modifications to the present utility model. If these modifications and variations fall within the scope of the claims of the present utility model and its equivalent technologies, they should all be considered as the protection scope of the present utility model.

Claims

1. A chlorosilane tail gas absorption device, comprising a primary absorption tower (1) and a secondary absorption tower (2), characterized in that: A first connecting pipe (5) and a second connecting pipe (6) are provided in parallel at the lower parts of the primary absorption tower (1) and the secondary absorption tower (2); a first shut-off valve (501) and a third shut-off valve (601) are provided at one end of the first connecting pipe (5) and the second connecting pipe (6) close to the primary absorption tower (1), respectively; a second shut-off valve (502) and a fourth shut-off valve (602) are provided at one end of the first connecting pipe (5) and the second connecting pipe (6) close to the secondary absorption tower (2), respectively; the first connecting pipe (5) and the second connecting pipe (6) are both connected to a high-pressure water pipeline (7); a first high-pressure water valve (701) is provided between the first connecting pipe (5) and the high-pressure water pipeline (7), and a second high-pressure water valve (702) is provided between the second connecting pipe (6) and the high-pressure water pipeline (7).

2. The chlorosilane tail gas absorption device according to claim 1, characterized in that: The top of the primary absorption tower (1) is connected to an exhaust gas pipeline (8), and the upper part of the primary absorption tower (1) is connected to a nitrogen pipeline (10); a spray device is provided in the primary absorption tower (1) and the secondary absorption tower (2), and the spray device is connected to an alkaline water pipeline (9); a tower bottom water pool (4) is provided at the bottom of the primary absorption tower (1) and the secondary absorption tower (2), and the top of the secondary absorption tower (2) is connected to a water seal tank (3).

3. The chlorosilane tail gas absorption device according to claim 2, characterized in that: A venting pipeline (301) is provided on the water seal tank (3).

4. The chlorosilane tail gas absorption device according to claim 2, characterized in that: A remote pressure gauge is provided on the exhaust gas pipeline (8).

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