Cold hydrogenation chlorosilane on-line detection equipment and method, cold hydrogenation production system and production method

Abstract

The invention discloses cold hydrogenation chlorosilane online detection equipment and method, and a cold hydrogenation production system and method. The equipment comprises a primary pretreatment unit, a secondary pretreatment unit, a heat preservation unit and a detection unit, the primary pretreatment unit comprises a sample inlet pipeline, a silicon powder filter and a pressure reducing valve; the heat preservation unit comprises a heat tracing piece and a heat tracing box body, and the secondary pretreatment unit is arranged in the heat tracing box body and comprises a first pipeline, a first coil pipe, a first filter, a vaporizer and an adsorber; and the detection unit is communicated with the gas outlet of the adsorber. According to the method, silicon powder and metal chloride impurities such as aluminum chloride and ferric chloride in the cold hydrogenated chlorosilane can be removed before detection, so that online detection on the components and concentration of the cold hydrogenated chlorosilane is effectively realized, and a real-time basis is provided for adjusting the raw material ratio and reaction conditions in the cold hydrogenated production process; therefore, the raw material ratio and the reaction conditions in the cold hydrogenation production process are adjusted in time according to the online detection result, and the conversion rate of the cold hydrogenation reaction is improved.

Description

Technical Field

[0001] This invention belongs to the field of polycrystalline silicon technology, specifically relating to an online detection device and method for cold hydrogenation of chlorosilanes, and a cold hydrogenation production system and production method. Background Technology

[0002] Among existing polysilicon production processes, the modified Siemens process is relatively advanced. The cold hydrogenation process is the main method for producing trichlorosilane, which involves the synthesis of trichlorosilane from silicon tetrachloride, silicon powder, and hydrogen through a cold hydrogenation reaction in a gas-solid fluidized bed reactor.

[0003] The equation is:

[0004]

[0005] However, in the aforementioned cold hydrogenation reaction, in addition to the formation of trichlorosilane, numerous side reactions occur, generating chlorosilane gases such as dichlorodichlorosilane, methyldichlorosilane, methyltrichlorosilane, and trimethylchlorosilane, as well as chloride impurities such as aluminum chloride and ferric chloride. This significantly affects the conversion rate of the cold hydrogenation reaction. To facilitate the control of the cold hydrogenation reaction and improve its conversion rate, it is necessary to monitor the composition of the reactant gases in the gas-solid fluidized bed reactor in real time.

[0006] Currently, analytical equipment for online detection of chlorosilane component concentration in polysilicon production processes is typically used to detect the content of various gases in the exhaust gas system, with the sample being a gas phase (e.g., patent CN111289689A), or to detect dichlorosilane in the chlorosilane in the reduction system, with the detected chlorosilane being a gas-liquid mixed phase (e.g., patent CN114184709A).

[0007] Compared to the tail gas system and reduction system in polysilicon production processes, cold hydrogenated chlorosilanes contain a significant amount of solid particles such as silicon powder, as well as gaseous impurities such as aluminum chloride and ferric chloride. To achieve online detection of the concentration of various components in cold hydrogenated chlorosilanes, it is necessary to first remove the silicon powder and impurities such as aluminum chloride and ferric chloride from the cold hydrogenated chlorosilanes. However, existing analytical equipment for online detection of chlorosilane component concentrations in polysilicon production processes lacks the corresponding technical means and cannot meet the online detection requirements of chlorosilanes in cold hydrogenation processes. Summary of the Invention

[0008] The technical problem this invention aims to solve is to address the shortcomings of existing technologies by providing an online detection device and method for cold hydrogenation chlorosilanes. By pretreating the chlorosilane gas at the outlet of the cold hydrogenation fluidized bed, impurities such as silicon powder, aluminum chloride, and ferric chloride can be removed before detection. This effectively enables online detection of the components and concentrations of cold hydrogenation chlorosilanes, providing real-time data for adjusting the raw material ratio and reaction conditions during the cold hydrogenation production process, thereby further improving the conversion rate of the cold hydrogenation reaction. This invention also provides a cold hydrogenation production system including the aforementioned online detection device and a cold hydrogenation production method including the aforementioned online detection method. Based on the online detection results, the raw material ratio and reaction conditions during the cold hydrogenation production process can be adjusted in a timely manner to improve the conversion rate of the cold hydrogenation reaction.

[0009] The technical solution of the present invention to solve the above-mentioned technical problems is:

[0010] According to a first aspect of the present invention, an online detection device for cold hydrochlorosilanes is provided, comprising a primary pretreatment unit, a secondary pretreatment unit, a heat preservation unit, and a detection unit, wherein:

[0011] The primary pretreatment unit includes a sample inlet pipe, a silicon powder filter, and a pressure reducing valve. The inlet end of the sample inlet pipe is located inside the cold hydrogenation process pipe and is used to obtain chlorosilane samples from the cold hydrogenation process pipe in real time. The silicon powder filter is connected to the outlet end of the sample inlet pipe and is used to receive the chlorosilane samples and remove the silicon powder therein. The pressure reducing valve is located at the gas outlet of the silicon powder filter.

[0012] The heat preservation unit includes a heat tracing component and a heat tracing box. The secondary pretreatment unit is located inside the heat tracing box and includes a first pipe, a first coil, a first filter, a vaporizer, and an adsorber. The inlet end of the first pipe is connected to the silica powder filter through a pressure reducing valve, and the heat tracing component is provided outside the first pipe to ensure that the chlorosilanes and metal chlorides in the chlorosilane sample are in a gaseous state. The first filter is connected to the outlet end of the first pipe through the first coil. The first coil is used to liquefy and condense the metal chlorides in the chlorosilane sample. The first filter is used to remove the liquefied metal chlorides. The vaporizer is connected to the first filter and is used to vaporize the residual metal chlorides in the chlorosilane sample. The adsorber is connected to the vaporizer and is used to adsorb the vaporized metal chlorides.

[0013] The detection unit is connected to the gas outlet of the adsorber and is used to detect the chlorosilane sample after adsorption treatment.

[0014] Optionally, the sample inlet direction at the inlet end of the sample inlet pipe is opposite to the flow direction of the chlorosilane gas in the cold hydrogenation process pipe.

[0015] Optionally, the secondary pretreatment unit further includes a reserved pipe, a second coil, and a second filter. The inlet end of the reserved pipe is connected to the first pipe, and a pipe regulating valve is provided on the reserved channel. The inlet end of the second filter is connected to the outlet end of the reserved pipe through the second coil, and the outlet end of the second filter is connected to the vaporizer, which constitutes a spare channel. The spare channel is arranged in parallel with the channel formed by the first coil and the first filter.

[0016] Optionally, the detection unit includes a second pipeline, a sample injection pipeline, and an online chromatograph. The second pipeline is connected to the gas outlet of the adsorber, and the online chromatograph is connected to the second pipeline through the sample injection pipeline, which is equipped with an injection control valve.

[0017] Optionally, the device further includes a sample reflux unit, which includes a sample reflux pipe, a sample outlet pipe, a second valve, and a third valve, wherein:

[0018] The sample reflux pipe is connected to the sample inlet pipe, and the second valve is located on the sample reflux pipe;

[0019] The inlet end of the sample outlet pipe is connected to the sample return pipe, the third valve is located on the sample outlet pipe, and the outlet end of the sample outlet pipe is connected to the cold hydrogenation process pipe and is located downstream of the inlet end of the sample inlet pipe.

[0020] Optionally, the inlet end of the sample outlet pipe is also connected to the gas outlet of the silicon powder filter, and the third valve is located downstream of the connection between the sample outlet pipe and the sample return pipe.

[0021] Optionally, the device further includes an exhaust gas recovery unit, which includes a third pipeline, a cold hydrazine, and an exhaust gas recovery pipeline, wherein:

[0022] The cold hydrazine is connected to the detection unit through a third pipe, which is used to cool and liquefy the chlorosilane in the detected exhaust gas.

[0023] The exhaust gas recovery pipeline is connected to cold hydrazine and is used to discharge non-condensable gases from the cold hydrazine into the exhaust gas pipeline network for recovery.

[0024] Optionally, the exhaust gas recovery unit further includes a seventh pipe, the inlet of which is connected to a silicon powder filter and the outlet of which is connected to a cold hydrazine.

[0025] Optionally, the device further includes a purging unit, which comprises a nitrogen inlet pipe, a nitrogen heater, a fourth pipe, a fifth pipe, and a sixth pipe, wherein:

[0026] The nitrogen inlet pipe is connected to the nitrogen supply device to introduce nitrogen as a purging gas;

[0027] The inlet end of the nitrogen heater is connected to the nitrogen inlet pipe, and the outlet end of the nitrogen heater is connected to the silicon powder filter through the fourth pipe and to the second pipe through the fifth pipe.

[0028] The two ends of the sixth pipe are connected to the second pipe and the third pipe, respectively.

[0029] According to a second aspect of the present invention, an online detection method for cold hydrogenated chlorosilanes is provided, wherein the above-described online detection method for cold hydrogenated chlorosilanes is used for detection, and the steps include:

[0030] The chlorosilane sample in the cold hydrogenation process pipeline is obtained in real time through the sample inlet pipe, and the chlorosilane sample is sent to the silicon powder filter to remove the silicon powder.

[0031] The chlorosilane sample after removing silicon powder is fed into the first coil through the first pipe. The temperature of the first coil is controlled at 80-100℃, so that the metal chloride in the chlorosilane sample is liquefied and condensed in the first coil. Then, it is passed through the first filter to remove the liquefied metal chloride. Then, it is passed through the vaporizer to vaporize the residual metal chloride in the chlorosilane sample. Then, it is adsorbed by the adsorber to obtain the sample to be tested.

[0032] The sample to be tested is sent into the detection unit for testing.

[0033] Optionally, before sending the chlorosilane sample into the silicon powder filter, the process further includes: opening the second valve and the third valve to allow the chlorosilane sample to flow back into the cold hydrogenation process pipeline through the sample inlet pipe, the sample reflux pipe, and the sample outlet pipe until the reflux reaches a stable state.

[0034] Optionally, before opening the second and third valves to allow the chlorosilane sample to flow back into the cold hydrogenation process pipeline through the sample inlet pipeline, sample return pipeline, and sample outlet pipeline, the process also includes: introducing nitrogen gas as a purging gas, heating it, and then purging various pipelines in the equipment, with the nitrogen temperature controlled above 130°C.

[0035] Optionally, after the sample to be tested is sent into the detection unit for testing, the method further includes: sending the tested exhaust gas into a cold hydrazine to cool and liquefy the chlorosilane in the exhaust gas; and discharging the non-condensable gas in the cold hydrazine into the exhaust gas pipeline for recovery.

[0036] Optionally, after the tested exhaust gas is sent into the cold hydrazine, the process also includes: introducing nitrogen as a purging gas, heating it, and then purging the second pipeline, with the nitrogen temperature controlled above 130°C.

[0037] Optionally, the temperature of the chlorosilane sample is controlled above 250°C before it enters the silicon powder filter, and the temperature of the chlorosilane sample in the first pipeline is controlled above 130°C.

[0038] According to a third aspect of the present invention, a cold hydrogenation production system is provided, comprising a cold hydrogenation process pipeline and the aforementioned online detection device for cold hydrogenation chlorosilanes, wherein the inlet end of the sample inlet pipeline in the online detection device is located inside the cold hydrogenation process pipeline, enabling real-time acquisition and online detection of chlorosilane samples.

[0039] According to a fourth aspect of the present invention, a cold hydrogenation production method is provided, comprising the above-described online detection method for cold hydrogenated chlorosilanes, specifically:

[0040] During the cold hydrogenation production process, chlorosilane samples are obtained from the cold hydrogenation process pipeline in real time and detected online.

[0041] Based on the test results, the raw material ratio and reaction conditions in the cold hydrogenation production process were adjusted to improve the conversion rate of the cold hydrogenation reaction.

[0042] Beneficial effects:

[0043] The online detection equipment and method for cold hydrogenated chlorosilanes of the present invention, by pretreating the chlorosilane gas at the outlet of the cold hydrogenated fluidized bed, can remove silicon powder and metal chloride impurities such as aluminum chloride and ferric chloride before detection. This can effectively realize online detection of the components and concentrations of cold hydrogenated chlorosilanes, providing real-time basis for adjusting the raw material ratio and reaction conditions in the cold hydrogenation production process, thereby further improving the conversion rate of the cold hydrogenation reaction.

[0044] The cold hydrogenation production system and method of the present invention, because it includes the above-mentioned online detection equipment for cold hydrogenation chlorosilane, can adjust the raw material ratio and reaction conditions in the cold hydrogenation production process in a timely manner according to the online detection results, thereby improving the conversion rate of the cold hydrogenation reaction. Attached Figure Description

[0045] Figure 1 This is a schematic diagram of the online detection device for cold hydrochlorosilane in an embodiment of the present invention.

[0046] In the diagram: 1-Cold hydrogenation process pipeline, 2-Sample inlet, 3-First valve, 4-Sample inlet pipeline, 5-Second valve, 6-Sample reflux pipeline, 7-Sample outlet pipeline, 8-Third valve, 9-Sample outlet, 10-Silicon powder filter, 11-Silicon powder collection tank, 12-Pressure reducing valve, 13-First pipeline, 14-First coil, 15-First filter, 16-Pipeline regulating valve, 17-Second coil, 18-Second filter, 19-Reserved pipeline, 20-Vaporizer, 21-Adsorber, 2 2-Second pipeline, 23-Sample injection pipeline, 24-Injection control valve, 25-Online chromatograph, 26-Third pipeline, 27-Nitrogen inlet, 28-First check valve, 29-Nitrogen inlet pipeline, 30-Nitrogen heater, 31-Second check valve, 32-Fourth pipeline, 33-First nitrogen control valve, 34-Fifth pipeline, 35-Third check valve, 36-Second nitrogen control valve, 37-Sixth pipeline, 38-Seventh pipeline, 39-Cold trap, 40-Tail gas recovery pipeline, 41-Heating box. Detailed Implementation

[0047] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0048] To address the lack of existing technologies capable of meeting the online detection requirements for chlorosilanes in cold hydrogenation processes, this invention discloses an online detection device and method for chlorosilanes in cold hydrogenation processes. The device comprises a primary pretreatment unit, a secondary pretreatment unit, a heat preservation unit, and a detection unit, wherein:

[0049] The primary pretreatment unit includes a sample inlet pipe, a silicon powder filter, and a pressure reducing valve. The inlet end of the sample inlet pipe is located inside the cold hydrogenation process pipe and is used to obtain chlorosilane samples from the cold hydrogenation process pipe in real time. The silicon powder filter is connected to the outlet end of the sample inlet pipe and is used to receive the chlorosilane samples and remove the silicon powder therein. The pressure reducing valve is located at the gas outlet of the silicon powder filter.

[0050] The heat preservation unit includes a heat tracing component and a heat tracing box. The secondary pretreatment unit is located inside the heat tracing box and includes a first pipe, a first coil, a first filter, a vaporizer, and an adsorber. The inlet end of the first pipe is connected to the silica powder filter through a pressure reducing valve, and the heat tracing component is provided outside the first pipe to ensure that the chlorosilanes and metal chlorides in the chlorosilane sample are in a gaseous state. The first filter is connected to the outlet end of the first pipe through the first coil. The first coil is used to liquefy and condense the metal chlorides in the chlorosilane sample. The first filter is used to remove the liquefied metal chlorides. The vaporizer is connected to the first filter and is used to vaporize the residual metal chlorides in the chlorosilane sample. The adsorber is connected to the vaporizer and is used to adsorb the vaporized metal chlorides.

[0051] The detection unit is connected to the gas outlet of the adsorber and is used to detect the chlorosilane sample after adsorption treatment.

[0052] Accordingly, the present invention also provides a cold hydrogenation production system including the above-mentioned online detection equipment for cold hydrogenation chlorosilanes and a cold hydrogenation production method including the above-mentioned online detection method for cold hydrogenation chlorosilanes.

[0053] Example 1

[0054] like Figure 1 As shown, this embodiment discloses an online detection device for cold hydrochlorosilanes, including a primary pretreatment unit, a secondary pretreatment unit, a heat preservation unit, and a detection unit, wherein:

[0055] The primary pretreatment unit includes a sample inlet pipe 4, a silicon powder filter 10, and a pressure reducing valve 12. The inlet end of the sample inlet pipe 4 (i.e., sample inlet 2) is located inside the cold hydrogenation process pipe 1 and serves as the inlet for the chlorosilane gas sample to be tested. It is used to obtain the chlorosilane sample from the cold hydrogenation process pipe in real time. The silicon powder filter 10 is connected to the outlet end of the sample inlet pipe 4 and is used to receive the chlorosilane sample and remove the silicon powder therein. The pressure reducing valve 12 is located at the gas outlet of the silicon powder filter 10.

[0056] The heat preservation unit includes a heat tracing element (not shown in the figure) and a heat tracing box 41. The secondary pretreatment unit is located inside the heat tracing box 41 and includes a first pipe 13, a first coil 14, a first filter 15, a vaporizer 20, and an adsorber 21. The inlet end of the first pipe 13 is connected to the silica powder filter 10 through a pressure reducing valve 12, and the heat tracing element is provided outside the first pipe 13 to ensure that the chlorosilane and metal chlorides (such as aluminum chloride and ferric chloride) in the chlorosilane sample are in a gaseous state. The first filter 15 is connected to the outlet end of the first pipe 13 through the first coil 14. The first coil 14 is used to liquefy and condense the metal chlorides in the chlorosilane sample. The first filter 15 is used to remove the liquefied metal chlorides. The vaporizer 20 is connected to the first filter 15 and is used to vaporize the residual metal chlorides in the chlorosilane sample. The adsorber 21 is connected to the vaporizer 20 and is used to adsorb the vaporized metal chlorides.

[0057] The detection unit is connected to the gas outlet of the adsorber 21 and is used to detect the chlorosilane sample after adsorption treatment.

[0058] In this embodiment, a first valve 3 is provided on the sample inlet pipe 4 to control the opening and closing of the sample feed pipe.

[0059] In this embodiment, the heat tracing element is an electric heat tracing element, and the heat tracing temperature of the first pipe 13 is not lower than 130°C to ensure that chlorosilane, aluminum chloride, and ferric chloride are in a gaseous state.

[0060] In this embodiment, the temperature of the heat tracing box is controlled at 80-100°C to ensure that the metal chlorides in the chlorosilane gas are liquefied and condensed, thereby removing aluminum chloride and ferric chloride impurities from the chlorosilane gas.

[0061] In this embodiment, the adsorber 21 is a gas adsorption column.

[0062] In this embodiment, the bottom of the silicon powder filter 10 is also connected to the silicon powder collection tank 11 for collecting the removed silicon powder.

[0063] In some embodiments, the sample inlet direction at the inlet end of the sample inlet pipe 4 is opposite to the flow direction of the chlorosilane gas in the cold hydrogenation process pipe 1.

[0064] In some embodiments, the secondary pretreatment unit further includes a reserved pipe 19, a second coil 17, and a second filter 18, wherein:

[0065] The inlet end of the reserved pipe 19 is connected to the first pipe 13. A pipe regulating valve 16 is provided on the reserved pipe 19. The inlet end of the second filter 18 is connected to the outlet end of the reserved pipe 19 through the second coil 17. The outlet end of the second filter 18 is connected to the vaporizer 21. It constitutes a backup channel. The backup channel is arranged in parallel with the channel formed by the first coil 14 and the first filter 15. When the first coil is blocked, it is switched to the backup channel.

[0066] In some embodiments, the detection unit includes a second pipeline 22, a sample injection pipeline 23, and an online chromatograph 25. The second pipeline 22 is connected to the gas outlet of the adsorber 21, and the online chromatograph 25 is connected to the second pipeline 22 via the sample injection pipeline 23. An injection control valve 24 is provided on the sample injection pipeline 23. The chlorosilane gas sample undergoes primary and secondary pretreatment sequentially, and then enters the online chromatograph for detection through the second pipeline and the sample injection pipeline.

[0067] In some embodiments, the device of this embodiment further includes a sample reflux unit, which includes a sample reflux pipe 6, a sample outlet pipe 7, a second valve 5, and a third valve 8, wherein:

[0068] The sample return pipe 6 is connected to the sample inlet pipe 4, and the second valve 5 is located on the sample return pipe 6.

[0069] The inlet end of the sample outlet pipe 7 is connected to the sample return pipe 6. The third valve 8 is installed on the sample outlet pipe 7. The outlet end of the sample outlet pipe 7 (i.e., the sample outlet 9) is connected to the cold hydrogenation process pipe 1 and is located downstream of the inlet end 2 of the sample inlet pipe 4.

[0070] In some embodiments, the inlet end of the sample outlet pipe 7 is also connected to the gas outlet of the silicon powder filter 10, and the third valve 3 is located downstream of the connection between the sample outlet pipe 7 and the sample return pipe 6.

[0071] In some embodiments, the device of this embodiment further includes an exhaust gas recovery unit, which includes a third pipe 26, a cold hydrazine 39, and an exhaust gas recovery pipe 40, wherein:

[0072] The cold hydrazine 26 is connected to the online chromatograph 25 in the detection unit through a third pipe 26, which is used to cool and liquefy the chlorosilane in the detected tail gas for recycling.

[0073] The exhaust gas recovery pipe 40 is connected to the cold hydrazine and is used to discharge the non-condensable gases in the cold hydrazine into the exhaust gas pipeline network for recovery.

[0074] In some embodiments, the exhaust gas recovery unit further includes a seventh pipe 38, the inlet of which is connected to the silicon powder filter 10, and the outlet of which is connected to the cold hydrazine 39.

[0075] In some embodiments, the device of this embodiment further includes a purging unit, which includes a nitrogen inlet pipe 29, a nitrogen heater 30, a fourth pipe 32, a fifth pipe 34, and a sixth pipe 37, wherein:

[0076] The inlet end of the nitrogen inlet pipe 29 (i.e., nitrogen inlet 27) is connected to a nitrogen supply device (such as a nitrogen pipeline or nitrogen cylinder) to introduce nitrogen as a purging gas.

[0077] The inlet end of the nitrogen heater 30 is connected to the nitrogen inlet pipe 27, and the outlet end of the nitrogen heater 30 is connected to the silicon powder filter 10 through the fourth pipe 32 and to the second pipe 22 through the fifth pipe 34. The nitrogen heater 30 is used to heat the introduced nitrogen gas. The temperature of the hot nitrogen gas is not lower than 130°C. That is to say, the purging gas of the equipment in this embodiment is hot nitrogen gas.

[0078] The two ends of the sixth pipe 37 are connected to the second pipe 22 and the third pipe 26, respectively.

[0079] In this embodiment, the nitrogen inlet pipe 29 is equipped with a first check valve 28, the fourth pipe 32 is equipped with a second check valve 31, the fifth pipe 34 is equipped with a first nitrogen control valve 33 and a third check valve 35, and the sixth pipe 37 is equipped with a first nitrogen control valve 36.

[0080] In this embodiment, the sample inlet pipe 4, sample return pipe 6, sample outlet pipe 7, silicon powder filter 10, first pipe 13, fourth pipe 32, and fifth pipe 34 are also equipped with heat tracing components.

[0081] The working process of the cold hydrochlorosilane online detection device in this embodiment is described in detail below:

[0082] 1. Open the nitrogen inlet 27 at the connection between the nitrogen inlet pipe 29 and the nitrogen pipeline network or nitrogen cylinder, and purge the various pipes in the equipment with nitrogen to ensure that the air and moisture in the pipes are removed. The purged gas is discharged from the seventh pipe 38 and the third pipe 26.

[0083] 2. Open the first valve 3 to allow the chlorosilane gas sample to enter the sample inlet pipe 4 from the cold hydrogenation process pipe 1. Open the second valve 5 and the third valve 8 to allow the chlorosilane gas sample to flow in the sample inlet pipe 4, the sample return pipe 6, and the sample outlet pipe 7.

[0084] 3. After the chlorosilane gas flows stably in the reflux unit, close the second valve 5 to allow the chlorosilane gas sample to enter the silicon powder filter 10. After filtration, the chlorosilane gas enters the first pipeline 13 through the pressure reducing valve 12. The pressure of the chlorosilane gas after being reduced by the pressure reducing valve 12 is 0.2 MPa.

[0085] 4. The chlorosilane gas sample passes through the first coil 14, the first filter 15, the vaporizer 20, and the adsorber 21 in sequence from the first pipeline 13 for secondary pretreatment to remove impurities such as aluminum chloride and ferric chloride from the chlorosilane gas sample.

[0086] 5. After secondary pretreatment, the chlorosilane gas sample enters the online chromatograph 25 through the second pipeline 22 and the sample injection pipeline 23 for detection.

[0087] 6. The chlorosilane gas sample after testing is recovered through the third pipeline 26, cold trap 39, and tail gas recovery pipeline 40;

[0088] 7. After the test is completed, open the first nitrogen control valve 33. Nitrogen gas purges the second pipeline 22 through the fifth pipeline 34. The purging gas enters the third pipeline 26 through the sixth pipeline 37, and then enters the exhaust gas network through the exhaust gas recovery pipeline 40.

[0089] It should be noted that, in the above process, the sample inlet pipe 4, sample return pipe 6, sample outlet pipe 7, and silicon powder filter 10 need to be controlled at a temperature of not less than 250℃, the first pipe 13 needs to be controlled at a temperature of not less than 130℃ to ensure that the chlorosilane gas and metal chloride are in a gaseous state, the nitrogen temperature in the fourth pipe 32 and the fifth pipe 34 needs to be controlled at a temperature of not less than 130℃, and the temperature of the heat tracing box 41 needs to be controlled at 80~100℃ to ensure that the metal chloride is liquefied and that the chlorosilane is in a gaseous state.

[0090] The online detection equipment for cold hydrogenation chlorosilanes in this embodiment pre-treats the chlorosilane gas at the outlet of the cold hydrogenation fluidized bed, removing silicon powder and metal chloride impurities such as aluminum chloride and ferric chloride before detection. This effectively enables online detection of the components and concentrations of cold hydrogenation chlorosilanes, providing real-time data for adjusting the raw material ratio and reaction conditions in the cold hydrogenation production process, thereby further improving the conversion rate of the cold hydrogenation reaction.

[0091] Example 2

[0092] This embodiment discloses an online detection method for cold-hydrochlorosilanes, which uses the above-described online detection method for cold-hydrochlorosilanes, and the steps include:

[0093] The chlorosilane sample in the cold hydrogenation process pipeline 1 is obtained in real time through the sample inlet pipe 4, and the chlorosilane sample is sent to the silicon powder filter 10 to remove the silicon powder.

[0094] The chlorosilane sample after removing silicon powder is fed into the first coil 14 through the first pipe 13. The temperature of the first coil 14 is controlled at 80-100°C, so that the metal chloride in the chlorosilane sample is liquefied and condensed in the first coil. Then, the liquefied metal chloride is removed by the first filter 15. Then, it is passed into the vaporizer 20 to vaporize the residual metal chloride in the chlorosilane sample. Then, the vaporized metal chloride is adsorbed by the adsorber 21 to obtain the sample to be tested.

[0095] The sample to be tested is sent into the detection unit for testing.

[0096] In some embodiments, the process further includes: […] before feeding the chlorosilane sample into the silica powder filter.

[0097] Open the second valve 5 and the third valve 8 to allow the chlorosilane sample to flow back to the cold hydrogenation process pipeline 1 through the sample inlet pipeline 4, the sample reflux pipeline 6, and the sample outlet pipeline 7 until the reflux reaches a stable state.

[0098] In some embodiments, before opening the second valve 5 and the third valve 8 to allow the chlorosilane sample to flow back into the cold hydrogenation process pipeline 1 through the sample inlet pipeline 4, the sample reflux pipeline 6, and the sample outlet pipeline 7, the following steps are also included:

[0099] Nitrogen gas is introduced through nitrogen inlet pipe 29 as a purging gas and heated by nitrogen heater 30 to purge various pipes in the equipment. The nitrogen temperature is controlled above 130℃.

[0100] In some embodiments, after the sample to be tested is sent into the detection unit for detection, the method further includes:

[0101] The tested exhaust gas is sent into cold hydrazine 39 to cool and liquefy the chlorosilane in the exhaust gas.

[0102] The non-condensable gases in the cold hydrazine 39 are discharged into the exhaust gas network through the exhaust gas recovery pipe 40 for recovery.

[0103] In some embodiments, after the tested exhaust gas is introduced into the cold hydrazine 39, the following steps are also included:

[0104] Nitrogen gas is introduced through nitrogen inlet pipe 29 as a purging gas and heated by nitrogen heater 30 to purge the second pipe 22. The nitrogen temperature is controlled above 130°C.

[0105] In some embodiments, the method further includes: after the sample testing is completed, when the silicon powder is discharged from the silicon powder filter 10, depressurization is performed through the seventh pipe 38 and the tail gas recovery pipe 40, and the silicon powder in the silicon powder filter is discharged through the nitrogen inlet pipe 29 by ammonia replacement.

[0106] In some embodiments, the temperature of the chlorosilane sample is controlled above 250°C before it enters the silicon powder filter 10, and the temperature of the chlorosilane sample in the first pipe is controlled above 130°C.

[0107] The online detection method for cold hydrogenated chlorosilanes in this embodiment pre-treats the chlorosilane gas at the outlet of the cold hydrogenated fluidized bed, removing impurities such as silicon powder, aluminum chloride, and ferric chloride before detection. This effectively enables online detection of the components and concentrations of cold hydrogenated chlorosilanes, providing real-time data for adjusting the raw material ratio and reaction conditions in the cold hydrogenation production process, thereby further improving the conversion rate of the cold hydrogenation reaction.

[0108] Example 3

[0109] This embodiment discloses a cold hydrogenation production system, including a cold hydrogenation process pipeline and the above-mentioned online detection equipment for cold hydrogenation chlorosilanes. The inlet end of the sample inlet pipeline in the online detection equipment is located inside the cold hydrogenation process pipeline, which can acquire chlorosilane samples in real time and perform online detection.

[0110] The cold hydrogenation production system of this embodiment includes the online detection equipment for cold hydrogenation chlorosilanes described above. Therefore, it can adjust the raw material ratio and reaction conditions in the cold hydrogenation production process in a timely manner based on the online detection results, thereby improving the conversion rate of the cold hydrogenation reaction.

[0111] Example 4

[0112] This embodiment discloses a cold hydrogenation production method, which includes the above-described online detection method for cold hydrogenated chlorosilanes, specifically:

[0113] During the cold hydrogenation production process, chlorosilane samples are obtained from the cold hydrogenation process pipeline in real time and detected online.

[0114] Based on the test results, the raw material ratio and reaction conditions in the cold hydrogenation production process were adjusted to improve the conversion rate of the cold hydrogenation reaction.

[0115] The cold hydrogenation production method of this embodiment includes the online detection method for cold hydrogenated chlorosilanes described above. Therefore, the raw material ratio and reaction conditions in the cold hydrogenation production process can be adjusted in a timely manner according to the online detection results, thereby improving the conversion rate of the cold hydrogenation reaction.

[0116] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. An online detection device for cold hydrochlorosilanes, characterized in that, It includes a primary pretreatment unit, a secondary pretreatment unit, a heat preservation unit, and a detection unit; The primary pretreatment unit includes a sample inlet pipe (4), a silicon powder filter (10), and a pressure reducing valve (12). The inlet end of the sample inlet pipe is located inside the cold hydrogenation process pipe (1) for obtaining chlorosilane samples from the cold hydrogenation process pipe in real time. The silicon powder filter is connected to the outlet end of the sample inlet pipe for receiving chlorosilane samples and removing silicon powder therein. The pressure reducing valve is located at the gas outlet of the silicon powder filter. The heat preservation unit includes a heat tracing component and a heat tracing box (41). The secondary pretreatment unit is located inside the heat tracing box and includes a first pipe (13), a first coil (14), a first filter (15), a vaporizer (20), and an adsorber (21). The inlet end of the first pipe is connected to the silicon powder filter through a pressure reducing valve, and the heat tracing component is provided outside the first pipe to ensure that the chlorosilane and metal chloride in the chlorosilane sample are in a gaseous state. The first filter is connected to the outlet end of the first pipe through the first coil. The first coil is used to liquefy and condense the metal chloride in the chlorosilane sample. The first filter is used to remove the liquefied metal chloride. The vaporizer is connected to the first filter and is used to vaporize the residual metal chloride in the chlorosilane sample. The adsorber is connected to the vaporizer and is used to adsorb the vaporized metal chloride. The detection unit is connected to the gas outlet of the adsorber and is used to detect the chlorosilane sample after adsorption treatment.

2. The online detection device for cold hydrochlorosilanes according to claim 1, characterized in that, The sample inlet direction at the inlet end of the sample inlet pipe is opposite to the flow direction of chlorosilane gas in the cold hydrogenation process pipe.

3. The online detection device for cold hydrochlorosilanes according to claim 1, characterized in that, The secondary pretreatment unit also includes a reserved pipe (19), a second coil (17), and a second filter (18). The inlet end of the reserved pipe is connected to the first pipe, and a pipe regulating valve is installed on the reserved channel. The inlet end of the second filter is connected to the outlet end of the reserved pipe through a second coil, and the outlet end of the second filter is connected to the vaporizer, forming a backup channel. The backup channel is arranged in parallel with the channel formed by the first coil and the first filter.

4. The online detection device for cold hydrochlorosilane according to any one of claims 1 to 3, characterized in that, The detection unit includes a second pipeline (22), a sample injection pipeline (23), and an online chromatograph (25). The second pipeline is connected to the gas outlet of the adsorber, and the online chromatograph is connected to the second pipeline through a sample injection pipeline, which is equipped with an injection control valve.

5. The online detection device for cold hydrochlorosilanes according to claim 4, characterized in that, The device also includes a sample reflux unit, which includes a sample reflux pipe (6), a sample outlet pipe (7), a second valve (5), and a third valve (8). The sample reflux pipe is connected to the sample inlet pipe, and the second valve is located on the sample reflux pipe. The inlet end of the sample outlet pipe is connected to the sample return pipe, the third valve is located on the sample outlet pipe, and the outlet end of the sample outlet pipe is connected to the cold hydrogenation process pipe and is located downstream of the inlet end of the sample inlet pipe.

6. The online detection device for cold hydrochlorosilanes according to claim 5, characterized in that, The inlet end of the sample outlet pipe is also connected to the gas outlet of the silicon powder filter, and the third valve is located downstream of the connection between the sample outlet pipe and the sample return pipe.

7. The online detection device for cold hydrochlorosilanes according to claim 5, characterized in that, The device also includes an exhaust gas recovery unit, which includes a third pipe (26), a cold hydrazine (39), and an exhaust gas recovery pipe (40); The cold hydrazine is connected to the detection unit through a third pipe, which is used to cool and liquefy the chlorosilane in the detected exhaust gas. The exhaust gas recovery pipeline is connected to cold hydrazine and is used to discharge non-condensable gases from the cold hydrazine into the exhaust gas pipeline network for recovery.

8. The online detection device for cold hydrochlorosilanes according to claim 7, characterized in that, The exhaust gas recovery unit also includes a seventh pipe (38), the inlet end of which is connected to a silicon powder filter and the outlet end of which is connected to a cold hydrazine.

9. The online detection device for cold hydrochlorosilanes according to claim 7, characterized in that, The device also includes a purging unit, which includes a nitrogen inlet pipe (29), a nitrogen heater (30), a fourth pipe (32), a fifth pipe (34), and a sixth pipe (37); The nitrogen inlet pipe is connected to the nitrogen supply device to introduce nitrogen as a purging gas; The inlet end of the nitrogen heater is connected to the nitrogen inlet pipe, and the outlet end of the nitrogen heater is connected to the silicon powder filter through the fourth pipe and to the second pipe through the fifth pipe. The two ends of the sixth pipe are connected to the second pipe and the third pipe, respectively.

10. A method for online detection of cold hydrochlorosilanes, characterized in that, The detection is performed using the online detection method for cold hydrochlorosilanes according to any one of claims 1-9, the steps of which include: The chlorosilane sample in the cold hydrogenation process pipeline is obtained in real time through the sample inlet pipe, and the chlorosilane sample is sent to the silicon powder filter to remove the silicon powder. The chlorosilane sample after removing silicon powder is fed into the first coil through the first pipe. The temperature of the first coil is controlled at 80-100℃, so that the metal chloride in the chlorosilane sample is liquefied and condensed in the first coil. Then, it is passed through the first filter to remove the liquefied metal chloride. Then, it is passed through the vaporizer to vaporize the residual metal chloride in the chlorosilane sample. Then, it is adsorbed by the adsorber to obtain the sample to be tested. The sample to be tested is sent into the detection unit for testing.

11. The online detection method for cold hydrochlorosilane according to claim 10, characterized in that, Before feeding the chlorosilane sample into the silica powder filter, the following steps are also included: Open the second and third valves to allow the chlorosilane sample to flow back into the cold hydrogenation process pipeline through the sample inlet pipe, sample reflux pipe, and sample outlet pipe until the reflux reaches a stable state.

12. The online detection method for cold hydrochlorosilane according to claim 11, characterized in that, Before opening the second and third valves to allow the chlorosilane sample to flow back into the cold hydrogenation process pipeline through the sample inlet pipe, sample reflux pipe, and sample outlet pipe, the process also includes: Nitrogen gas is introduced as a purging gas and heated to purge various pipes in the equipment. The nitrogen temperature is controlled above 130°C.

13. The online detection method for cold hydrochlorosilane according to claim 10, characterized in that, After the sample to be tested is sent into the detection unit for testing, the process also includes: sending the tested exhaust gas into a cold hydrazine to cool and liquefy the chlorosilane in the exhaust gas. Non-condensable gases in the cold hydrazine are discharged into the tail gas pipeline for recovery.

14. The online detection method for cold hydrochlorosilanes according to claim 13, characterized in that, After the tested exhaust gas is fed into the cold hydrazine, the process also includes: Nitrogen gas is introduced as a purging gas and heated to purge the second pipeline. The nitrogen temperature is controlled above 130°C.

15. The online detection method for cold hydrochlorosilane according to any one of claims 10-14, characterized in that, Before the chlorosilane sample enters the silicon powder filter, the temperature of the chlorosilane sample is controlled above 250°C; The temperature of the chlorosilane sample in the first pipeline is controlled above 130°C.

16. A cold hydrogenation production system, comprising a cold hydrogenation process pipeline, characterized in that, It also includes the online detection device for cold hydrogenated chlorosilanes as described in any one of claims 1-9, wherein the inlet end of the sample inlet pipeline in the online detection device is located inside the cold hydrogenation process pipeline, and is capable of acquiring chlorosilane samples in real time and performing online detection.

17. A cold hydrogenation production method, characterized in that, Including the online detection method for cold hydrochlorosilanes according to any one of claims 10-15, During the cold hydrogenation production process, chlorosilane samples are obtained from the cold hydrogenation process pipeline in real time and detected online. Based on the test results, the raw material ratio and reaction conditions in the cold hydrogenation production process were adjusted to improve the conversion rate of the cold hydrogenation reaction.

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