Polycrystalline silicon tail gas recovery system and polycrystalline silicon production system

Abstract

The utility model relates to the technical field of polycrystalline silicon production, in particular to a polycrystalline silicon tail gas recovery system and a polycrystalline silicon production system. The polycrystalline silicon tail gas recovery system comprises a filter, an electromagnetic pulse injection valve and a blowback gas bag, a hydrogen blowback pipeline is arranged between the electromagnetic pulse injection valve and the filter, the electromagnetic pulse injection valve is connected with the gas outlet end of the blowback gas bag, and the gas inlet end of the blowback gas bag is connected with a source hydrogen pipeline. And a pressure relief hole of the electromagnetic pulse injection valve is connected with a pressure relief hole exhaust pipeline. A hydrogen back-blowing pipeline is connected with an electromagnetic pulse injection valve, the gas inlet end of the electromagnetic pulse injection valve is connected with a back-blowing gas bag, a pressure relief hole of the electromagnetic pulse injection valve is connected with a pressure relief hole exhaust pipeline, after a system carries out one-time back-blowing operation, the pressure relief hole can be opened for pressure relief, then the pressure relief hole exhaust pipeline is closed, and hydrogen released from the pressure relief hole can be recycled through the pressure relief hole exhaust pipeline. Therefore, the safety of a production site is guaranteed, meanwhile, the hydrogen consumption can be reduced by recovering the hydrogen through the pressure relief hole exhaust pipeline, and the production cost of an enterprise is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of polysilicon production, and in particular to a polysilicon tail gas recovery system and a polysilicon production system. Background Art

[0002] In the regeneration system of the tail gas recovery process in the polysilicon production system, the filter receives reduced and hydrogenated hydrogen, in which the hydrogen will carry a certain degree of silicon powder. After working for a certain period of time, the filtered silicon powder will adhere to the filter element, causing the filter element to be blocked. The filter pressure difference becomes high, which is not conducive to the use of the filter. Therefore, it is necessary to use an electromagnetic pulse spray valve to regularly backflush the filter element.

[0003] When the electromagnetic pulse spray valve is used, it is energized. After the electromagnetic coil is controlled, the exciting current begins to rise exponentially. After the armature is magnetized and exceeds the resistance of the spring and other related factors, it begins to move. Then the air gap becomes smaller, the coil inductance increases, and the attraction is suppressed. Finally, the armature and the magnetic yoke contact to the closed position. Due to the relationship between the moving iron core and the pressure relief hole, the pressure relief hole will open for pressure relief every time the electromagnetic pulse spray valve moves, and then close to release a certain amount of gas. Since the back-blowing gas commonly used in the filter of the polysilicon production system is hydrogen, the pressure relief hole will release hydrogen into the working environment after the back-blowing operation, so there will be certain safety hazards on site. In addition, the leaked hydrogen will also cause hydrogen consumption, thereby increasing the production cost of the enterprise. Utility Model Content

[0004] Based on this, the present application provides a polysilicon tail gas recovery system and a polysilicon production system to solve the problem of hydrogen leakage from the pressure relief hole, resulting in safety hazards on site, and increased production costs for the enterprise due to hydrogen consumption.

[0005] On the one hand, the present application provides a polysilicon tail gas recovery system, including a filter, an electromagnetic pulse spray valve and a back-blowing air bag, a hydrogen back-blowing pipeline is arranged between the electromagnetic pulse spray valve and the filter, the air inlet end of the hydrogen back-blowing pipeline is connected to the air outlet end of the electromagnetic pulse spray valve, the air outlet end of the hydrogen back-blowing pipeline is connected to the filter, the air inlet end of the electromagnetic pulse spray valve is connected to the air outlet end of the back-blowing air bag, the air inlet end of the back-blowing air bag is connected to the source hydrogen pipeline, and the pressure relief hole of the electromagnetic pulse spray valve is connected to the pressure relief hole exhaust pipeline.

[0006] In a possible implementation, the polysilicon tail gas recovery system further includes a control unit, and the control unit is connected to the electromagnetic pulse injection valve.

[0007] In a possible implementation, the back-blowing gas bag is connected to a first pressure device, the source hydrogen pipeline is provided with a first valve, and the control unit is respectively connected to the first pressure device and the first valve.

[0008] In a possible implementation, the air inlet end of the filter is connected to the tail gas input pipeline, the bottom of the filter is connected to the silicon powder collection pipeline, and the top of the filter is connected to the hydrogen output pipeline.

[0009] In one possible implementation, the polysilicon tail gas recovery system also includes a control unit, the tail gas input pipeline is connected to a second pressure vessel, the hydrogen output pipeline is connected to a third pressure vessel, and the control unit is respectively connected to the second pressure vessel, the third pressure vessel and the electromagnetic pulse injection valve.

[0010] In a possible implementation, the polysilicon tail gas recovery system further includes a control unit, a differential pressure gauge is provided on the filter, and the control unit is respectively connected to the differential pressure gauge and the electromagnetic pulse injection valve.

[0011] In a possible implementation, the tail gas input pipeline is provided with a second valve, and the hydrogen output pipeline is provided with a third valve.

[0012] In a possible implementation, the pressure relief hole exhaust pipeline is connected to the hydrogen output pipeline.

[0013] In a possible implementation, the pressure relief hole exhaust line is provided with a fourth valve.

[0014] On the other hand, the present application provides a polysilicon production system, which includes the above-mentioned polysilicon tail gas recovery system.

[0015] The polysilicon tail gas recovery system and polysilicon production system provided in the present application. An electromagnetic pulse injection valve is connected to the air inlet end of the hydrogen backflush pipeline, the air inlet end of the electromagnetic pulse injection valve is connected to the backflush air bag, and the pressure relief hole of the electromagnetic pulse injection valve is connected to the pressure relief hole exhaust pipeline. After the system performs a backflush operation, the pressure relief hole will open to relieve pressure, and then close, and the pressure relief hole exhaust pipeline will recover the hydrogen leaked from the pressure relief hole. Thereby ensuring the safety of the production site, and at the same time, the recovery of hydrogen by the pressure relief hole exhaust pipeline can reduce hydrogen consumption and reduce the production cost of the enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 One of the structural schematic diagrams of the polysilicon tail gas recovery system provided in the embodiment of the present application;

[0018] Figure 2The second structural schematic diagram of the polysilicon tail gas recovery system provided in the embodiment of the present application;

[0019] Figure 3 This is the third structural schematic diagram of the polysilicon tail gas recovery system provided in the embodiment of the present application.

[0020] Description of reference numerals:

[0021] 100-polysilicon tail gas recovery system; 10-filter; 11-tail gas input pipeline; 12-silicon powder collection pipeline; 13-hydrogen output pipeline; 14-second pressure vessel; 15-third pressure vessel; 16-differential pressure gauge; 17-second valve; 18-third valve; 19-fifth valve; 20-electromagnetic pulse injection valve; 21-hydrogen backflush pipeline; 22-pressure relief hole exhaust pipeline; 23-fourth valve; 30-backflush air bag; 31-source hydrogen pipeline; 32-first pressure vessel; 33-first valve; 34-compressor; 40-control unit; 50-silicon powder recovery tank; 51-silicon powder discharge pipeline; 52-sixth valve; 53-charging pipeline; 54-pressure relief pipeline; 55-seventh valve; 56-eighth valve. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme in the embodiment of the present application will be described in more detail below in conjunction with the drawings in the preferred embodiments of the present application. In the drawings, the same or similar reference numerals throughout represent the same or similar parts or parts with the same or similar functions. The described embodiments are part of the embodiments of the present application, not all of the embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limitations on the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application. The embodiments of the present application are described in detail below in conjunction with the drawings.

[0023] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, or it can be an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0024] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are orientations or positional relationships based on the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0025] The terms "first", "second" and "third" (if any) in the specification and claims of this application and the above drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0026] In addition, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, for example, a process, method, system, product, or display comprising a series of steps or elements is not necessarily limited to those steps or elements explicitly listed, but may include other steps or elements not explicitly listed or inherent to such process, method, product, or display.

[0027] In the regeneration system of the tail gas recovery process in the polysilicon production system, the filter receives reduced and hydrogenated hydrogen, in which the hydrogen will carry a certain degree of silicon powder. After working for a certain period of time, the filtered silicon powder will adhere to the filter element, causing the filter element to be blocked. The filter pressure difference becomes high, which is not conducive to the use of the filter. Therefore, it is necessary to use an electromagnetic pulse spray valve to regularly backflush the filter element.

[0028] When the electromagnetic pulse spray valve is used, it is energized. After the electromagnetic coil is controlled, the exciting current begins to rise exponentially. After the armature is magnetized and exceeds the resistance of the spring and other related factors, it begins to move. Then the air gap becomes smaller, the coil inductance increases, and the attraction is suppressed. Finally, the armature and the magnetic yoke contact to the closed position. Due to the relationship between the moving iron core and the pressure relief hole, the pressure relief hole will open for pressure relief every time the electromagnetic pulse spray valve moves, and then close to release a certain amount of gas. Since the back-blowing gas commonly used in the filter of the polysilicon production system is hydrogen, the pressure relief hole will release hydrogen into the working environment after the back-blowing operation, so there will be certain safety hazards on site. In addition, the leaked hydrogen will also cause hydrogen consumption, thereby increasing the production cost of the enterprise.

[0029] After repeated thinking and verification, the inventor found that if an exhaust pipeline is connected to the pressure relief hole without changing the original process and valve group to guide the leaked hydrogen, when the system performs backflush operation, the hydrogen generated by the pressure relief hole will flow out through the exhaust pipeline for recovery. This ensures the safety of the production site, and at the same time, the hydrogen recovered by the exhaust pipeline can be reused, which can reduce hydrogen consumption and reduce the production cost of the enterprise.

[0030] In view of this, the present application provides a polysilicon exhaust gas recovery system and a polysilicon production system. The polysilicon exhaust gas recovery system includes a filter, an electromagnetic pulse spray valve and a back-blowing air bag. A hydrogen back-blowing pipeline is provided between the electromagnetic pulse spray valve and the filter. The air inlet end of the hydrogen back-blowing pipeline is connected to the air outlet end of the electromagnetic pulse spray valve, the air outlet end of the hydrogen back-blowing pipeline is connected to the filter, the air inlet end of the electromagnetic pulse spray valve is connected to the air outlet end of the back-blowing air bag, the air inlet end of the back-blowing air bag is connected to the source hydrogen pipeline, and the pressure relief hole of the electromagnetic pulse spray valve is connected to the pressure relief hole exhaust pipeline.

[0031] The electromagnetic pulse injection valve is connected to the air inlet of the hydrogen backflush pipeline, the air inlet of the electromagnetic pulse injection valve is connected to the backflush air bag, and the pressure relief hole of the electromagnetic pulse injection valve is connected to the pressure relief hole exhaust pipeline. When the system performs a backflush operation, the pressure relief hole will open to release the pressure, and then close, and the pressure relief hole exhaust pipeline will recover the hydrogen leaked from the pressure relief hole. Thereby ensuring the safety of the production site, and at the same time, the recovery of hydrogen by the pressure relief hole exhaust pipeline can reduce hydrogen consumption and reduce the production cost of the enterprise.

[0032] The contents of the present application will be described in detail below in conjunction with the accompanying drawings so that those skilled in the art can understand the contents of the present application more clearly and in detail.

[0033] Figure 1 This is one of the structural schematic diagrams of the polysilicon tail gas recovery system provided in the embodiment of the present application. Figure 2 This is the second structural schematic diagram of the polysilicon tail gas recovery system provided in an embodiment of the present application. Figure 3 This is the third structural schematic diagram of the polysilicon tail gas recovery system provided in the embodiment of the present application.

[0034] like Figure 1 As shown, the polysilicon tail gas recovery system 100 provided in the embodiment of the present application includes a filter 10, an electromagnetic pulse spray valve 20 and a back-blowing air bag 30. The electromagnetic pulse spray valve 20 is connected to the filter 10. The back-blowing air bag 30 is connected to the electromagnetic pulse spray valve 20. The filter 10 is used to filter the tail gas including hydrogen and silicon powder generated in the polysilicon production system. The back-blowing air bag 30 is used to provide back-blowing hydrogen to the filter 10 to back-blow the filter element in the filter 10. The electromagnetic pulse spray valve 20 is used to control the blowing of the back-blowing hydrogen in the back-blowing air bag 30.

[0035] Specifically, a hydrogen backflush pipeline 21 is provided between the electromagnetic pulse spray valve 20 and the filter 10. The air inlet end of the hydrogen backflush pipeline 21 is connected to the air outlet end of the electromagnetic pulse spray valve 20. The air outlet end of the hydrogen backflush pipeline 21 is connected to one side of the top of the filter 10. The hydrogen backflush pipeline 21 is used to feed backflush hydrogen into the cylinder of the filter 10 to purge silicon powder attached to the outer wall of the filter element in the filter 10.

[0036] The air inlet of the electromagnetic pulse spray valve 20 is connected to the air outlet of the back-blowing air bag 30. The air inlet of the back-blowing air bag 30 is connected to the source hydrogen pipeline 31. The pressure relief hole of the electromagnetic pulse spray valve 20 is connected to the pressure relief hole exhaust pipeline 22. The source hydrogen pipeline 31 is used to input hydrogen for back-blowing. The pressure relief hole exhaust pipeline 22 is used to guide the hydrogen leaked from the pressure relief hole.

[0037] Specifically, the pressure relief hole exhaust pipeline 22 is connected to the low pressure part of the hydrogen regeneration system so that the collected hydrogen can be processed in the regeneration system and then recovered and reused.

[0038] In one possible implementation, Figure 2 As shown, the polysilicon tail gas recovery system 100 further includes a control unit 40. The control unit 40 is connected to the electromagnetic pulse injection valve 20. The control unit 40 is used to control the operation of the electromagnetic pulse injection valve 20.

[0039] In a possible implementation, the back-blowing gas bag 30 is connected to a first pressure device 32. A first valve 33 is provided on the source hydrogen pipeline 31. The first pressure device 32 is used to monitor the gas pressure of the back-blowing gas bag 30. The first valve 33 is used to control the source hydrogen pipeline 31 to input hydrogen into the back-blowing gas bag 30.

[0040] The control unit 40 is also connected to the first pressure device 32 and the first valve 33 respectively. The control unit 40 is used to receive the pressure value of the first pressure device 32, and judge whether the air pressure of the back-blowing air bag 30 is normal according to the pressure value of the first pressure device 32 and the preset pressure value. If the air pressure is low, the first valve 33 is controlled to open to input hydrogen into the back-blowing air bag 30.

[0041] In some embodiments, the air pressure of the back-blowing air bag 30 is in the range of 0.8 MPa-0.9 MPa.

[0042] In one possible implementation, Figure 2 As shown, a compressor 34 is also provided on the source hydrogen pipeline 31, and the compressor 34 is used to pressurize the hydrogen input from the source hydrogen pipeline 31 to the back-blowing gas bag 30, so that the gas pressure value of the back-blowing gas bag 30 is maintained within a certain range.

[0043] In a possible implementation, the air inlet end of the filter 10 is connected to the tail gas input pipeline 11. The bottom of the filter 10 is connected to the silicon powder collection pipeline 12. The top of the filter 10 is connected to the hydrogen output pipeline 13. The tail gas input pipeline 11 is used to input the tail gas to be filtered into the filter 10. The silicon powder collection pipeline 12 is used to guide the silicon powder generated after filtering by the filter 10 out of the filter 10. The hydrogen output pipeline 13 is used to output the hydrogen obtained after filtering by the filter 10.

[0044] Specifically, the air inlet end of the filter 10 is arranged on one side of the filter 10 close to the bottom, and the filter element of the filter 10 is located above the air inlet end of the filter 10 , so that the exhaust gas entering the filter 10 is filtered by the filter element and output from the top of the filter 10 .

[0045] In a possible implementation, the tail gas input pipeline 11 is connected to a second pressure device 14. The hydrogen output pipeline 13 is connected to a third pressure device 15. The second pressure device 14 is used to monitor the gas pressure of the tail gas input pipeline 11. The third pressure device 15 is used to monitor the gas pressure of the hydrogen output pipeline 13.

[0046] The control unit 40 is also connected to the second pressure device 14 and the third pressure device 15 respectively. The control unit 40 is used to receive the pressure values ​​of the second pressure device 14 and the third pressure device 15, and judge whether the pressure difference of the filter 10 is normal according to the pressure value of the second pressure device 14, the pressure value of the third pressure device 15 and the size of the preset pressure difference value. If it is normal, it means that the filter element can work normally, and the electromagnetic pulse spray valve 20 is controlled to be closed, and the back-blowing operation is not performed; if it is abnormal, it means that the filter element is blocked and cannot work normally, and the electromagnetic pulse spray valve 20 needs to be controlled to be opened for back-blowing operation.

[0047] In one possible implementation, Figure 3 As shown, a differential pressure gauge 16 can also be directly arranged on the filter 10, and both ends of the differential pressure gauge 16 are respectively connected to the two sides of the filter element of the filter 10. The differential pressure gauge 16 can directly display the differential pressure value of the filter 10.

[0048] The control unit 40 is connected to the differential pressure gauge 16. The control unit 40 receives the differential pressure value of the differential pressure gauge 16, and determines whether the differential pressure of the filter 10 is normal according to the differential pressure value of the differential pressure gauge 16 and the size of the preset differential pressure value. If it is normal, it means that the filter element can work normally, and the electromagnetic pulse spray valve 20 is controlled to be closed, and the back-blowing operation is not performed; if it is abnormal, it means that the filter element is blocked and cannot work normally, and the electromagnetic pulse spray valve 20 needs to be controlled to be opened for back-blowing operation.

[0049] In a possible implementation, the filter element of the filter 10 is made of a metal powder sintered filter element, the filter element is tubular and has a filtration accuracy of 1 μm-3 μm.

[0050] In a possible implementation, the tail gas input pipeline 11 is provided with a second valve 17 , and the hydrogen output pipeline 13 is provided with a third valve 18 .

[0051] By opening and closing the second valve 17 and the third valve 18, the filter 10 can be controlled to operate or be shut down for maintenance.

[0052] In a possible implementation, the control unit 40 is also connected to the second valve 17 and the third valve 18 respectively. The control unit 40 can control the opening and closing of the second valve 17 and the third valve 18 according to whether the filter 10 is working normally as determined above. If the filter 10 is working normally, the second valve 17 and the third valve 18 are controlled to be opened to perform filtering operations; if the filter 10 is not working normally, the second valve 17 and the third valve 18 are controlled to be closed, and the electromagnetic pulse spray valve 20 is opened to perform back-blowing operations, or the machine is shut down for repairs, etc. as needed.

[0053] In a possible implementation, the pressure relief hole exhaust pipeline 22 is connected to the hydrogen output pipeline 13 .

[0054] The pressure relief hole exhaust pipeline 22 is directly connected to the hydrogen output pipeline 13, which can facilitate the arrangement of the pipeline and save space.

[0055] In a possible implementation, the pressure relief hole exhaust pipeline 22 is provided with a fourth valve 23. The fourth valve 23 is used to control the opening and closing of the pressure relief hole exhaust pipeline 22.

[0056] Since the electromagnetic pulse spray valve 20 does not work continuously, the pressure relief hole does not continuously release hydrogen, and it is only discharged when the electromagnetic pulse spray valve 20 is working. At the same time, in order to prevent the hydrogen output from the hydrogen output pipeline 13 from flowing into the pressure relief hole exhaust pipeline 22, a fourth valve 23 is provided on the pressure relief hole exhaust pipeline 22 to control the opening and closing of the pressure relief hole exhaust pipeline 22.

[0057] In a possible implementation, the silicon powder collecting pipeline 12 is provided with a fifth valve 19 .

[0058] The discharge of silicon powder collected by the filter 10 can be controlled by opening and closing the fifth valve 19 .

[0059] In a possible implementation, the polysilicon tail gas recovery system 100 further includes a silicon powder recovery tank 50. The silicon powder recovery tank 50 is connected to the filter 10 via a silicon powder collection pipeline 12. The silicon powder recovery tank 50 is used to collect the filtered silicon powder.

[0060] In a possible implementation, the silicon powder recovery tank 50 is connected to a silicon powder discharge pipeline 51. The silicon powder discharge pipeline 51 is disposed at the bottom of the silicon powder recovery tank 50. The silicon powder discharge pipeline 51 is used to discharge the silicon powder collected by the silicon powder recovery tank 50 to the outside.

[0061] In a possible implementation, the silicon powder discharge pipeline 51 is provided with a sixth valve 52. The sixth valve 52 is used to control the discharge of the silicon powder collected in the silicon powder recovery tank 50.

[0062] In a possible implementation, one side of the silicon powder recovery tank 50 is connected to a pressure-charging pipeline 53, and the other side is connected to a pressure-releasing pipeline 54. The pressure-charging pipeline 53 is used to charge the silicon powder recovery tank 50 with replacement gas, preferably nitrogen in this embodiment, and the pressure-releasing pipeline 54 is used to discharge the waste gas replaced in the silicon powder recovery tank 50.

[0063] After the fifth valve 19 is opened, all the silicon powder falls into the silicon powder recovery tank 50. The fifth valve 19 is closed, and nitrogen is filled into the silicon powder recovery tank 50 through the pressure charging pipeline 53 for gas replacement. The waste gas is discharged through the pressure relief pipeline 54. The sixth valve 52 at the bottom of the silicon powder recovery tank 50 is opened, and the silicon powder is discharged by gravity, so that the silicon powder discharge is safe.

[0064] In a possible implementation, the charging line 53 is provided with a seventh valve 55 , and the depressurizing line 54 is provided with an eighth valve 56 .

[0065] By opening and closing the seventh valve 55 and the eighth valve 56 , the gas in the silicon powder recovery tank 50 can be adjusted, so that the silicon powder recovery tank 50 can collect or discharge silicon powder.

[0066] In a possible implementation, the first valve 33, the second valve 17, the third valve 18, the fourth valve 23, the fifth valve 19, the sixth valve 52, the seventh valve 55, and the eighth valve 56 are solenoid valves, which can be connected to the control unit 40 to achieve automated management.

[0067] When in use, the exhaust gas to be filtered enters the filter 10 from the exhaust gas input pipeline 11, is purified by the filter element of the filter 10, and then converges from the inside of the filter 10 to the top of the filter 10 for buffering, and then is discharged through the hydrogen output pipeline 13. Then, the large particles of silicon powder fall to the bottom of the filter 10 under the action of its own gravity, and another part of the finer silicon powder is adsorbed on the outer surface of the filter element. As the filtration continues, the silicon powder accumulated on the outer surface of the filter element continues to increase, and the running resistance of the filter 10 increases accordingly. When the running resistance reaches the specified running resistance value, that is, the difference between the pressure values ​​of the second pressure device 14 and the third pressure device 15, or After the pressure difference value of the differential pressure gauge 16 reaches the preset pressure difference value, the control unit 40 starts to control the electromagnetic pulse spray valve 20 to perform backblowing operation, automatically closes the second valve 17 and the third valve 18, and suspends the operation of the filter 10. Then, the electromagnetic pulse spray valve 20 is controlled to open, and the filter element is backblown with the hydrogen in the backblowing air bag 30, so that the silicon powder attached to the outer surface of the filter element is blown to the bottom of the filter 10, and then the silicon powder is discharged from the silicon powder collection pipeline 12 to the silicon powder recovery tank 50, and the backblowing is completed. The hydrogen leaked from the pressure relief hole of the electromagnetic pulse spray valve 20 is discharged to the hydrogen output pipeline 13 through the pressure relief hole exhaust pipeline 22.

[0068] The polysilicon tail gas recovery system 100 provided in the embodiment of the present application includes a filter 10, an electromagnetic pulse spray valve 20 and a back-blowing air bag 30. A hydrogen back-blowing pipeline 21 is provided between the electromagnetic pulse spray valve 20 and the filter 10. The air inlet end of the hydrogen back-blowing pipeline 21 is connected to the air outlet end of the electromagnetic pulse spray valve 20, and the air outlet end of the hydrogen back-blowing pipeline 21 is connected to the filter 10. The air inlet end of the electromagnetic pulse spray valve 20 is connected to the air outlet end of the back-blowing air bag 30, and the air inlet end of the back-blowing air bag 30 is connected to the source hydrogen pipeline 31. The pressure relief hole of the electromagnetic pulse spray valve 20 is connected to the pressure relief hole exhaust pipeline 22.

[0069] The air inlet of the hydrogen back-blowing pipeline 21 is connected to the electromagnetic pulse spray valve 20, the air inlet of the electromagnetic pulse spray valve 20 is connected to the back-blowing air bag 30, and the pressure relief hole of the electromagnetic pulse spray valve 20 is connected to the pressure relief hole exhaust pipeline 22. When the system performs a back-blowing operation, the pressure relief hole will be opened for pressure relief, and then closed, and the pressure relief hole exhaust pipeline 22 will recover the hydrogen leaked from the pressure relief hole. Thereby ensuring the safety of the production site, and at the same time, the recovery of hydrogen by the pressure relief hole exhaust pipeline 22 can reduce hydrogen consumption and reduce the production cost of the enterprise.

[0070] In addition, an embodiment of the present application further provides a polysilicon production system, in which the polysilicon tail gas recovery system 100 described above is provided.

[0071] The specific structure, working principle and function of the polysilicon tail gas recovery system 100 have been described in detail in the above embodiments and will not be repeated here.

[0072] It can be understood that in a polysilicon production system, multiple polysilicon tail gas recovery systems 100 can be set up, so that when one of the polysilicon tail gas recovery systems 100 is performing a backflushing operation, the remaining polysilicon tail gas recovery systems 100 can perform filtering without stopping for processing, thereby facilitating continuous production and improving production efficiency.

[0073] The polysilicon production system provided by the present application is connected to the electromagnetic pulse blowing valve 20 at the air inlet end of the hydrogen back-blowing pipeline 21, the air inlet end of the electromagnetic pulse blowing valve 20 is connected to the back-blowing air bag 30, and the pressure relief hole of the electromagnetic pulse blowing valve 20 is connected to the pressure relief hole exhaust pipeline 22. When the system performs a back-blowing operation, the pressure relief hole will be opened for pressure relief, and then closed, and the pressure relief hole exhaust pipeline 22 will recover the hydrogen leaked from the pressure relief hole. Thereby ensuring the safety of the production site, and at the same time, the recovery of hydrogen by the pressure relief hole exhaust pipeline 22 can reduce hydrogen consumption and reduce the production cost of the enterprise.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A polysilicon tail gas recovery system, characterized in that: It includes a filter, an electromagnetic pulse spray valve and a back-blowing air bag, a hydrogen back-blowing pipeline is arranged between the electromagnetic pulse spray valve and the filter, the air inlet end of the hydrogen back-blowing pipeline is connected to the air outlet end of the electromagnetic pulse spray valve, the air outlet end of the hydrogen back-blowing pipeline is connected to the filter, the air inlet end of the electromagnetic pulse spray valve is connected to the air outlet end of the back-blowing air bag, the air inlet end of the back-blowing air bag is connected to the source hydrogen pipeline, and the pressure relief hole of the electromagnetic pulse spray valve is connected to the pressure relief hole exhaust pipeline.

2. The polysilicon tail gas recovery system according to claim 1, characterized in that: The polysilicon tail gas recovery system also includes a control unit, and the control unit is connected to the electromagnetic pulse injection valve.

3. The polysilicon tail gas recovery system according to claim 2, characterized in that: The back-blowing gas bag is connected to a first pressure device, the source hydrogen pipeline is provided with a first valve, and the control unit is respectively connected to the first pressure device and the first valve.

4. The polysilicon tail gas recovery system according to claim 1, characterized in that: The air inlet end of the filter is connected to the tail gas input pipeline, the bottom of the filter is connected to the silicon powder collection pipeline, and the top of the filter is connected to the hydrogen output pipeline.

5. The polysilicon tail gas recovery system according to claim 4, characterized in that: The polysilicon tail gas recovery system also includes a control unit. The tail gas input pipeline is connected to a second pressure device, the hydrogen output pipeline is connected to a third pressure device, and the control unit is respectively connected to the second pressure device, the third pressure device and the electromagnetic pulse injection valve.

6. The polysilicon tail gas recovery system according to claim 4, characterized in that: The polysilicon tail gas recovery system also includes a control unit. A differential pressure gauge is arranged on the filter. The control unit is respectively connected to the differential pressure gauge and the electromagnetic pulse injection valve.

7. The polysilicon tail gas recovery system according to claim 4, characterized in that: The tail gas input pipeline is provided with a second valve, and the hydrogen output pipeline is provided with a third valve.

8. The polysilicon tail gas recovery system according to claim 4, characterized in that: The pressure relief hole exhaust pipeline is connected to the hydrogen output pipeline.

9. The polysilicon tail gas recovery system according to claim 1, characterized in that: The pressure relief hole exhaust pipeline is provided with a fourth valve.

10. A polysilicon production system, characterized in that: The polysilicon production system includes the polysilicon tail gas recovery system as described in any one of claims 1-9.

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