Silane gas detection and pretreatment integrated system

Abstract

The invention discloses a silane gas detection and pretreatment integrated system which comprises a detection cabinet and a front pretreatment box, and the front pretreatment box is sequentially provided with a first-stage pressure regulating valve group and a helium purging unit in the gas conveying direction of a gas supply pipeline; one end of the gas pipeline is connected to the gas outlet end of the gas supply pipeline, and the other end of the gas pipeline is connected in parallel with a first branch pipeline and a second branch pipeline; a moisture meter, a sample gas flowmeter and a first one-way valve are arranged on the first branch pipeline; the second branch pipeline is connected in parallel with a third branch pipeline and a fourth branch pipeline through a three-way reversing valve, the third branch pipeline is connected to the detection end of the gas chromatograph, and the fourth branch pipeline is connected to the gas inlet end of the vacuumizing pump. Helium purging and vacuumizing are adopted to ensure that no O2 exists in a system pipeline, the situation that silane gas reacts with residual air in the pipeline to generate silicon powder to block the pipeline is avoided, and the detection stability of the system and the accuracy of analysis data of a gas chromatograph are guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of silane gas detection, and specifically to an integrated system for silane gas detection and pretreatment. Background Art

[0002] Silane is a compound of silicon and hydrogen, which is a general term for a series of compounds. Silane is famous for its unique spontaneous combustion and explosiveness. It has a very wide spontaneous ignition range and extremely strong combustion energy, and it is also a colorless and toxic gas. Therefore, it is determined that it is a highly dangerous gas. Therefore, during the production process of silane, the sample gas content parameter is an important indicator for safe production and needs to be accurately measured. However, at present, the air in some on-site pipelines cannot be removed completely, resulting in the reaction of silane gas with the residual air in the pipeline to generate silicon powder, which causes pipeline blockage, affects the normal detection of the system, or causes deterioration or damage to the performance of the gas chromatograph, resulting in inaccurate analysis data, thus bringing economic losses and potential safety hazards. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide an integrated system for silane gas detection and pretreatment to solve the technical problems mentioned in the prior art.

[0004] An integrated system for silane gas detection and pretreatment, the system includes a detection cabinet and a pre-treatment box. The intake end of the pre-treatment box is connected to the silane gas production pipeline through a sampling joint, and the outlet end of the pre-treatment box is connected to the intake end of the detection cabinet; The pre-treatment box is provided with a gas supply pipeline connecting its intake end and outlet end, and a first pressure regulating valve group and a helium purging unit are sequentially arranged along the gas transmission direction of the gas supply pipeline; The detection cabinet is provided with a gas transmission pipeline, one end of which is connected to the outlet end of the gas supply pipeline, and the other end is connected in parallel with a first branch pipeline and a second branch pipeline; The first branch pipeline is sequentially provided with a moisture analyzer, a sample gas flowmeter and a first check valve along the gas transmission direction; The second branch pipeline is connected in parallel with a third branch pipeline and a fourth branch pipeline through a three-way reversing valve. The three-way reversing valve is used to switch the connection between the second branch pipeline and the third branch pipeline or the fourth branch pipeline. The third branch pipeline is connected to the detection end of the gas chromatograph, and the fourth branch pipeline is connected to the intake end of the vacuum pump; The moisture analyzer and the three-way reversing valve are respectively connected to the control terminal.

[0005] Optionally, the first pressure regulating valve group includes a first shut-off valve, a first filter, a first pressure reducing valve and a second shut-off valve sequentially arranged along the gas transmission direction of the gas supply pipeline; The first switching valve and the second switching valve are respectively a manual diaphragm valve or a pneumatic diaphragm valve.

[0006] Optionally, the helium purging unit has a high-pressure helium gas storage tank. The gas outlet end of the high-pressure helium gas storage tank is communicated with the gas supply pipeline through a pipeline, and a third switching valve is arranged at the gas outlet end of the high-pressure helium gas storage tank; The third switching valve is a pneumatic diaphragm valve.

[0007] Optionally, a secondary pressure regulating valve group is arranged at the gas inlet end of the gas transmission pipeline. The secondary pressure regulating valve group includes a fourth switching valve, a second filter, and a secondary pressure reducing valve arranged in sequence along the gas transmission direction of the gas transmission pipeline; The fourth switching valve is a pneumatic diaphragm valve.

[0008] Optionally, a bypass pipeline is connected in parallel on the side of the gas outlet end of the secondary pressure reducing valve of the gas transmission pipeline. A bypass flowmeter and a second one-way valve are arranged in sequence along the gas transmission direction of the bypass pipeline.

[0009] Optionally, the gas outlet end of the bypass pipeline, the gas outlet end of the first branch pipeline, and the gas outlet end of the vacuum pump are respectively communicated with the discharge pipeline; One end of the discharge pipeline is provided with a nitrogen purging device.

[0010] Optionally, the system further includes a SiH4 alarm. The SiH4 alarm and the primary pressure regulating valve group are respectively connected to the control terminal. The SiH4 alarm is used to detect the concentration of silane sample gas on the outer peripheral sides of the detection cabinet and the pre-treatment box and upload it to the control terminal. The control terminal controls the opening and closing of the primary pressure regulating valve group according to whether the received concentration of silane sample gas exceeds a preset monitoring range.

[0011] Optionally, a pressure gauge is installed at the gas inlet end of the vacuum pump.

[0012] Optionally, the three-way reversing valve is a pneumatic diaphragm valve.

[0013] Optionally, the pneumatic diaphragm valve is configured with a gas transmission and distribution unit. An electromagnetic valve is arranged between the gas transmission and distribution unit and the pneumatic diaphragm valve. The electromagnetic valve is connected to the control terminal. The control terminal controls the electromagnetic valve to open to connect the pneumatic diaphragm valve with the gas transmission and distribution unit. The gas transmission and distribution unit is used to drive the pneumatic diaphragm valve to open.

[0014] The beneficial effects that the present invention can produce include: The integrated system for detecting and preprocessing silane gas provided by the present invention uses helium purging and vacuum pumping to ensure that there is no O2 in the system pipeline, avoiding the reaction of silane gas with the residual air in the pipeline to generate silicon powder, which may cause pipeline blockage, thereby ensuring the stability of system detection and the accuracy of the analysis data of the gas chromatograph. At the same time, a moisture meter and several branch pipelines are designed to detect whether the dew point index of the silane sample gas meets the dew point parameter requirements of the working environment of the gas chromatograph, and discharge the unqualified silane sample gas through the branch pipelines, thereby avoiding damage to the gas chromatograph caused by the silane sample gas, reducing economic losses and avoiding potential safety hazards caused by the inability of the system to detect normally. Brief Description of the Drawings

[0015] Figure 1 is a schematic structural diagram of the integrated system for detecting and preprocessing silane gas of the present invention; Figure 2 is a schematic control diagram of the integrated system for detecting and preprocessing silane gas of the present invention; In the figure: 1. Detection cabinet, 2. Pre-front-end pretreatment box, 3. Gas supply pipeline, 4. Gas transmission pipeline, 5. First branch pipeline, 6. Second branch pipeline, 7. Moisture meter, 8. Sample gas flowmeter, 9. First one-way valve, 10. Three-way reversing valve, 11. Third branch pipeline, 12. Fourth branch pipeline, 13. Gas chromatograph, 14. Vacuum pump, 15. Control terminal, 16. First switch valve, 17. First filter, 18. First stage pressure reducing valve, 19. Second switch valve, 20. Helium high-pressure gas storage tank, 21. Third switch valve, 22. Fourth switch valve, 23. Second filter, 24. Second stage pressure reducing valve, 25. Bypass pipeline, 26. Bypass flowmeter, 27. Second one-way valve, 28. Discharge pipeline, 29. Nitrogen purging equipment, 30. SiH4 alarm, 31. Pressure gauge, 32. Gas transmission and distribution unit, 33. Solenoid valve. Detailed Embodiments

[0016] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0017] Such as Figure 1 and Figure 2As shown in the figure, the present invention provides an integrated system for detecting and preprocessing silane gas. The system includes a detection cabinet 1 and a pre-treatment box 2. The intake end of the pre-treatment box 2 is connected to the silane gas production pipeline through a sampling joint, and is used to collect a preset flow of silane sample gas and introduce it into the pre-treatment box 2 for pre-treatment. The specific operations of the pre-treatment are impurity removal, pressure regulation, and on-off control of the pipeline. The outlet end of the pre-treatment box 2 is connected to the intake end of the detection cabinet 1 to introduce the pre-treated silane sample gas into the detection cabinet 1 for detection and analysis. Among them, the pre-treatment box 2 is provided with a gas supply pipeline 3 connecting its intake end and outlet end, and a primary pressure regulating valve group and a helium purge unit are sequentially arranged along the gas transmission direction of the gas supply pipeline 3. The detection cabinet 1 is provided with a gas transmission pipeline 4, one end of which is connected to the outlet end of the gas supply pipeline 3, and the other end is connected in parallel with a first branch pipeline 5 and a second branch pipeline 6. The first branch pipeline 5 is sequentially provided with a moisture meter 7, a sample gas flowmeter 8, and a first one-way valve 9 along the gas transmission direction. The second branch pipeline 6 is connected in parallel with a third branch pipeline 11 and a fourth branch pipeline 12 through a three-way reversing valve 10. The three-way reversing valve 10 is used to switch the connection between the second branch pipeline 6 and the third branch pipeline 11 or the fourth branch pipeline 12. The third branch pipeline 11 is connected to the detection end of a gas chromatograph 13, and the fourth branch pipeline 12 is connected to the intake end of a vacuum pump 14. A pressure gauge 31 is installed at the intake end of the vacuum pump 14 to stop vacuum pumping when the detected vacuum degree inside the pipeline reaches a preset value. The primary pressure regulating valve group, the helium purge unit, the moisture meter 7, and the three-way reversing valve 10 are respectively connected to a control terminal 15.

[0018] In the above, before introducing the silane sample gas into the gas supply pipeline 3 through the sampling joint, the primary pressure regulating valve group is first set to the closed state, and the three-way reversing valve 10 is controlled to connect the second branch pipeline 6 with the fourth branch pipeline 12. Then, the vacuum pump 14 is controlled to extract the air in the gas supply pipeline 3, the gas transmission pipeline 4, the first branch pipeline 5, the second branch pipeline 6, and the fourth branch pipeline 12 to achieve a vacuum state inside the pipeline, avoiding the reaction between the silane gas and the residual air in the pipeline to generate silicon powder, which may cause pipeline blockage, thereby ensuring the stability of system detection and the accuracy of the analysis data of the gas chromatograph 13. Then, the helium purging unit is controlled to sequentially introduce helium into the gas supply pipeline 3, the gas transmission pipeline 4, the first branch pipeline 5, the second branch pipeline 6, and the fourth branch pipeline 12 for purging to remove impurities in the pipeline and the residual oxygen in the pipeline. After the purging operation is completed, the primary pressure regulating valve group is opened, so that the silane sample gas is introduced into the system and flows into the detection cabinet 1 after the input pressure is adjusted to the preset pressure value by the pre-treatment box 2. The dew point index of the silane sample gas is detected by the moisture meter 7 to check whether it meets the dew point parameter requirements of the working environment of the gas chromatograph 13. If the dew point index of the silane sample gas meets the dew point parameter requirements of the working environment of the gas chromatograph 13, the three-way reversing valve 10 is controlled to connect the second branch pipeline 6 with the third branch pipeline 11, and the silane sample gas is introduced into the detection end of the gas chromatograph 13 for detection. If the dew point index of the silane sample gas does not meet the dew point parameter requirements of the working environment of the gas chromatograph 13, the three-way reversing valve 10 is controlled to connect the second branch pipeline 6 with the fourth branch pipeline 12, and the silane sample gas is discharged through the fourth branch pipeline 12, thereby avoiding damage to the gas chromatograph 13 caused by the silane sample gas, reducing economic losses, and avoiding potential safety hazards caused by the system being unable to detect normally.

[0019] In the above, the joints of the gas supply pipeline 3, the gas transmission pipeline 4, the first branch pipeline 5, the second branch pipeline 6, the third branch pipeline 11, and the fourth branch pipeline 12 are all welded and connected by VCR joints, ensuring the tightness of the entire system and preventing air from entering the system. Moreover, the entire system uses helium purging and vacuum pumping to ensure that there is no O2 in the system pipeline, achieving the expected effects of high precision, high efficiency, and high protection.

[0020] Furthermore, the primary pressure regulating valve group includes a first switch valve 16, a first filter 17, a primary pressure reducing valve 18, and a second switch valve 19 arranged in sequence along the gas transmission direction of the gas supply pipeline 3. Among them, the first switch valve 16 and the second switch valve 19 are respectively manual diaphragm valves or pneumatic diaphragm valves. As Figure 1As shown in the figure, in this embodiment, the first switching valve 16 is a manual diaphragm valve, which is used to manually block the silane-like gas from entering the system. Compared with the automatic control valve group, it has higher safety in use and can avoid damage to the circuit and abnormal opening and closing. The second switching valve 19 is a pneumatic diaphragm valve, which is used to cut off the gas supply pipeline 3 in time during the operation stage of the system to block the silane-like gas from entering the system. The first filter 17 is used to filter the impurities contained in the silane-like gas, and the input pressure of the silane-like gas is adjusted to a preset pressure value through the primary pressure reducing valve 18 to ensure the stable and safe operation of the system.

[0021] Further, the helium purging unit has a high-pressure helium gas storage tank 20. The gas outlet end of the high-pressure helium gas storage tank 20 is connected to the gas supply pipeline 3 through a pipeline, and a third switching valve 21 is provided at the gas outlet end of the high-pressure helium gas storage tank 20 to control the opening and closing of the high-pressure helium gas storage tank 20. A secondary pressure regulating valve group is provided at the gas inlet end of the gas transmission pipeline 4. The secondary pressure regulating valve group includes a fourth switching valve 22, a second filter 23, and a secondary pressure reducing valve 24 arranged in sequence along the gas transmission direction of the gas transmission pipeline 4 to realize two-stage control of the silane-like gas and avoid damage to the moisture analyzer 7 or the gas chromatograph 13 caused by the silane-like gas after one set of filters or pressure reducing valves is damaged, thereby improving the safety in use of the system. Among the above, the second switching valve 19, the third switching valve 21, the fourth switching valve 22, and the three-way reversing valve 10 are pneumatic diaphragm valves respectively. Specifically, the pneumatic diaphragm valve is equipped with a gas transmission and distribution unit 32. An electromagnetic valve 33 is provided between the gas transmission and distribution unit 32 and the pneumatic diaphragm valve. The electromagnetic valve 33 is connected to the control terminal 15. The control terminal 15 controls the electromagnetic valve 33 to open to connect the pneumatic diaphragm valve with the gas transmission and distribution unit 32. The gas transmission and distribution unit 32 is used to drive the pneumatic diaphragm valve to open. When the corresponding pipeline needs to be closed, the corresponding electromagnetic valve 33 is controlled to close to cut off the pneumatic diaphragm valve from the gas transmission and distribution unit 32, thereby realizing the closing of the pneumatic diaphragm valve to close the corresponding pipeline.

[0022] Further, a bypass pipeline 25 is connected in parallel on the side of the gas outlet end of the secondary pressure reducing valve 24 of the gas transmission pipeline 4, which is used to discharge the excess silane-like gas introduced into the system from the bypass pipeline 25 to protect the overall pipeline and equipment of the system. A bypass flowmeter 26 and a second one-way valve 27 are arranged in sequence along the gas transmission direction of the bypass pipeline 25. By designing the bypass flowmeter 26, the flow rate of the silane-like gas can be controlled. Specifically, the output pressure of the secondary pressure reducing valve 24 can be controlled according to the flow rate value detected by the bypass flowmeter 26 to stabilize the pressure of the silane-like gas introduced into the gas transmission pipeline 4 to a preset constant value, thereby accurately regulating the output flow rate of the silane-like gas.

[0023] In the above, the outlet end of the bypass pipe 25, the outlet end of the first branch pipe 5, and the outlet end of the vacuum pump 14 are respectively connected to the discharge pipe 28; a nitrogen purging device 29 is provided at one end of the discharge pipe 28. By purging the discharge pipe 28 with the nitrogen purging device 29, it is possible to further prevent moisture and air from entering the system pipeline.

[0024] Furthermore, the system further includes an SiH4 alarm 30. The SiH4 alarm 30 and the first-stage pressure regulating valve group are respectively connected to the control terminal 15. The SiH4 alarm 30 is used to detect the concentration of silane-like gas on the outer periphery of the detection cabinet 1 and the pre-treatment box 2 and upload it to the control terminal 15. The control terminal 15 controls the opening and closing of the first-stage pressure regulating valve group according to whether the received concentration of silane-like gas exceeds the preset monitoring range. Specifically, when the concentration of silane-like gas exceeds the preset monitoring range, the second switching valve 19 is controlled to close to timely block the silane-like gas from entering the system. In this embodiment, the control terminal 15 is further connected to a DCS system and / or a fire protection system, so that when the SiH4 alarm 30 issues an alarm, the DCS system is controlled to turn on the exhaust fan to discharge the leaked silane-like gas to avoid poisoning of personnel; or the fire protection system is controlled to turn on the sprinkler device to spray water to prevent the silane-like gas from burning in the air and causing an explosion accident.

Claims

1. A silane gas detection and pretreatment integrated system, characterized in that, The system includes a detection cabinet (1) and a pre - treatment box (2). The intake end of the pre - treatment box (2) is connected to the silane gas production pipeline through a sampling joint, and the outlet end of the pre - treatment box (2) is connected to the intake end of the detection cabinet (1); The pre - treatment box (2) is provided with a gas supply pipeline (3) connecting its intake end and outlet end, and a primary pressure regulating valve group and a helium purging unit are sequentially arranged along the gas transmission direction of the gas supply pipeline (3); The detection cabinet (1) is provided with a gas transmission pipeline (4). One end of it is connected to the outlet end of the gas supply pipeline (3), and the other end is connected in parallel with a first branch pipeline (5) and a second branch pipeline (6); The first branch pipeline (5) is sequentially provided with a moisture meter (7), a sample gas flowmeter (8) and a first check valve (9) along the gas transmission direction; The second branch pipeline (6) is connected in parallel with a third branch pipeline (11) and a fourth branch pipeline (12) through a three - way reversing valve (10). The three - way reversing valve (10) is used to switch the connection between the second branch pipeline (6) and the third branch pipeline (11) or the fourth branch pipeline (12). The third branch pipeline (11) is connected to the detection end of a gas chromatograph (13), and the fourth branch pipeline (12) is connected to the intake end of a vacuum pump (14); The moisture meter (7) and the three - way reversing valve (10) are respectively connected to a control terminal (15).

2. The silane gas detection and pretreatment integrated system according to claim 1, characterized in that, The primary pressure regulating valve group includes a first switch valve (16), a first filter (17), a primary pressure reducing valve (18) and a second switch valve (19) sequentially arranged along the gas transmission direction of the gas supply pipeline (3); The first switch valve (16) and the second switch valve (19) are respectively a manual diaphragm valve or a pneumatic diaphragm valve.

3. The silane gas detection and pretreatment integrated system according to claim 2, characterized in that, The helium purging unit has a high - pressure helium gas storage tank (20). The outlet end of the high - pressure helium gas storage tank (20) is connected to the gas supply pipeline (3) through a pipeline, and a third switch valve (21) is arranged at the outlet end of the high - pressure helium gas storage tank (20); The third switch valve (21) is a pneumatic diaphragm valve.

4. The silane gas detection and pretreatment integrated system according to claim 1, characterized in that, A secondary pressure regulating valve group is arranged at the intake end of the gas transmission pipeline (4). The secondary pressure regulating valve group includes a fourth switch valve (22), a second filter (23) and a secondary pressure reducing valve (24) sequentially arranged along the gas transmission direction of the gas transmission pipeline (4); The fourth switch valve (22) is a pneumatic diaphragm valve.

5. The silane gas detection and pretreatment integrated system according to claim 4, characterized in that, A bypass pipeline (25) is connected in parallel to the side of the outlet end of the gas transmission pipeline (4) where the secondary pressure reducing valve (24) is located. The bypass pipeline (25) is sequentially provided with a bypass flowmeter (26) and a second check valve (27) along the gas transmission direction.

6. The silane gas detection and pretreatment integrated system according to claim 5, characterized in that, The outlet end of the bypass pipeline (25), the outlet end of the first branch pipeline (5) and the outlet end of the vacuum pump (14) are respectively connected to a discharge pipeline (28); One end of the discharge pipeline (28) is provided with a nitrogen purging device (29).

7. The silane gas detection and pretreatment integrated system according to claim 1, characterized in that, The system further includes a SiH4 alarm (30). The SiH4 alarm (30) and the first-stage pressure regulating valve group are respectively connected to the control terminal (15). The SiH4 alarm (30) is used to detect the concentration of silane sample gas on the outer peripheral sides of the detection cabinet (1) and the pre-treatment box (2) and upload it to the control terminal (15). The control terminal (15) controls the opening and closing of the first-stage pressure regulating valve group according to whether the received concentration of silane sample gas exceeds a preset monitoring range.

8. The silane gas detection and pretreatment integrated system according to claim 1, characterized in that, A pressure gauge (31) is installed at the intake end of the vacuum pump (14).

9. The silane gas detection and pretreatment integrated system according to claim 1, characterized in that, The three-way directional valve (10) is a pneumatic diaphragm valve.

10. The silane gas detection and pretreatment integrated system according to any one of claims 3, 4 or 9, characterized in that, The pneumatic diaphragm valve is configured with a gas transmission and distribution unit (32). An electromagnetic valve (33) is arranged between the gas transmission and distribution unit (32) and the pneumatic diaphragm valve. The electromagnetic valve (33) is connected to the control terminal (15). The control terminal (15) controls the electromagnetic valve (33) to open to connect the pneumatic diaphragm valve to the gas transmission and distribution unit (32), and the gas transmission and distribution unit (32) is used to drive the pneumatic diaphragm valve to open.

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