Process gas circulation system for particle silicon product post-processing device

Abstract

The utility model discloses a process gas circulating system for a particle silicon product post-processing device, which comprises a process gas inlet header pipe, a process gas outlet header pipe, a gas outlet header pipe, a gas inlet pipe, a gas outlet pipe, a gas outlet pipe and a gas outlet pipe, wherein the process gas inlet header pipe is used for conveying process gas from a gas source to a gas inlet port of the post-processing device; the gas main pipe inlet valve is arranged on the process gas inlet main pipe and is used for controlling the supply quantity of the process gas source; a gas inlet of the silicon powder filter is connected with a gas outlet port of the post-treatment device through a process gas tail gas recovery main pipe, a gas outlet of the silicon powder filter is connected with a gas inlet port of the post-treatment device through a purified tail gas return pipeline, and the silicon powder filter is used for purifying process gas tail gas exhausted by the post-treatment device to form a process gas circulation loop; the first pressure gauge is arranged on the purified tail gas backflow pipeline and electrically connected with the gas main pipe inlet valve, and the first pressure gauge is used for measuring the pressure value of gas in the purified tail gas backflow pipeline; the system is configured to adjust the opening degree of the gas manifold inlet valve according to the measurement value of the first pressure gauge so as to supplement the pressure.

Description

Technical Field

[0001] The utility model relates to a process gas circulation system, in particular to a process gas circulation system for a granular silicon product post-processing device. Background Art

[0002] Post-processing is an important step before granular silicon products are packaged and sold. Granular silicon is packaged and sold after screening and dust removal. During the post-processing of granular silicon, the process gas introduced takes away the silicon powder in the granular silicon, and the gas is directly discharged after filtering and other treatments, which causes waste of process gas in the production process and increases the gas loss in the granular silicon processing process.

[0003] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of the utility model, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to ordinary technicians in this field. Utility Model Content

[0004] Purpose of the utility model: The technical problem to be solved by the utility model is to provide a process gas circulation system for a granular silicon product post-processing device in view of the deficiencies in the prior art, which can recycle the process gas and reduce the gas loss in the granular silicon processing process.

[0005] In order to solve the above technical problems, the utility model discloses a process gas circulation system for a granular silicon product post-processing device, wherein the process gas circulation system comprises a process gas inlet main pipe, a gas main pipe inlet valve, a silicon powder filter and a first pressure gauge.

[0006] The process gas inlet main pipe connects the inlet port of the granular silicon product post-processing device with an external process gas source, and is used to transport the process gas from the external process gas source to the inlet port of the post-processing device;

[0007] The gas main inlet valve is arranged on the process gas inlet main pipe, and is used to control the supply amount of the process gas source;

[0008] The silicon powder filter is a metal or ceramic filter used to separate silicon powder from process gas. The air inlet of the silicon powder filter is connected to the air outlet port of the post-processing device through the process gas tail gas recovery main pipe, and the air outlet of the silicon powder filter is connected to the air inlet port of the granular silicon product post-processing device through the purified tail gas return pipeline, which is used to purify the process gas tail gas discharged from the post-processing device to form a process gas circulation loop.

[0009] The first pressure gauge is arranged on the purified tail gas return pipeline and is used to measure the pressure value of the gas in the purified tail gas return pipeline.

[0010] The first pressure gauge is electrically connected to the gas main inlet valve, and the process gas circulation system is configured to adjust the opening of the gas main inlet valve according to the measurement value of the first pressure gauge to supplement the pressure.

[0011] In this embodiment, the process gas is recycled to achieve the effect of reducing gas loss.

[0012] Specifically, in order to prevent part of the process gas from being substandard after being filtered by the silicon powder filter, the process gas circulation system includes an oxygen concentration detector, a gas venting pipeline and a gas venting valve.

[0013] The oxygen concentration detector is arranged on the purified tail gas return pipeline, and is used to measure the oxygen content value in the gas in the purified tail gas return pipeline;

[0014] The air inlet port of the gas venting pipeline is connected to the purified tail gas return pipeline, and in the process gas flow direction, the connection is located downstream of the oxygen concentration detector and upstream of the connection between the process gas intake manifold and the air inlet port of the post-processing device;

[0015] A gas vent valve is arranged on the gas vent pipeline; and the process gas circulation system is configured to open and close the gas vent valve according to the oxygen content value.

[0016] In this embodiment, when the oxygen content in the process gas circulation system meets the standard, the gas is recycled, and when the oxygen content does not meet the standard, part of the gas is discharged; when the system pressure is insufficient, the pressure is supplemented through the process gas intake main pipe.

[0017] Specifically, there is more than one granular silicon product post-processing device, and each of the granular silicon product post-processing devices includes a screening device and a dust removal device, the air inlet of the screening device is connected to an air inlet branch of the screening device, the air inlet of the dust removal device is connected to an air inlet branch of the dust removal device, the other end of the air inlet branch of the screening device and the other end of the air inlet branch of the dust removal device are connected in parallel to the air inlet port of the granular silicon product post-processing device; the air outlet of the screening device is connected to an air outlet branch of the screening device, the air outlet of the dust removal device is connected to an air outlet branch of the dust removal device, the other end of the air outlet branch of the screening device and the other end of the air outlet branch of the dust removal device are connected in parallel to the air outlet port of the granular silicon product post-processing device.

[0018] Furthermore, the system also includes a valve assembly, and the valve assembly is used to control more than one of the granular silicon product post-processing devices to work selectively or simultaneously.

[0019] Specifically, the valve assembly includes an air inlet valve of a screening device, an air outlet valve of a screening device, an air inlet valve of a dust removal device, an air outlet valve of a dust removal device, a third gas flowmeter and a fourth gas flowmeter; for each of the post-processing devices of the granular silicon product, the air inlet valve of the dust removal device and the third gas flowmeter are arranged on the air inlet branch pipe of the dust removal device, and the air outlet valve of the screening device is arranged on the air outlet branch pipe of the screening device; the air inlet valve of the dust removal device and the fourth gas flowmeter are arranged on the air inlet branch pipe of the dust removal device, and the air outlet valve of the dust removal device is arranged on the air outlet branch pipe of the dust removal device.

[0020] In this embodiment, the screening device air inlet valve, the screening device air outlet valve and the third gas flow meter are used to control the inlet and outlet pressure and flow of the screening device. The dust removal device air inlet valve, the dust removal device air outlet valve and the fourth gas flow meter are used to control the inlet and outlet pressure and flow of the dust removal device.

[0021] Specifically, the process gas circulation system includes a circulation fan, and the circulation fan is used to provide power for the gas flow in the process gas circulation loop.

[0022] Specifically, the circulation fan is arranged on the purified tail gas return pipeline; in the gas flow direction in the purified tail gas return pipeline, the circulation fan is located upstream of the first pressure gauge. The circulation fan maintains the pressure of the circulation system.

[0023] Specifically, the process gas circulation system includes a second gas flow meter arranged on the process gas inlet main pipe, an oxygen content alarm arranged on the process gas exhaust recovery main pipe, a first process gas valve arranged on the purified exhaust gas return pipeline, and a vent control valve arranged at the vent port of the silicon powder filter, wherein the first process gas valve is located upstream of the circulation fan.

[0024] Furthermore, the process gas circulation system also includes a second pressure gauge arranged on the process gas tail gas recovery main pipe.

[0025] Furthermore, the process gas circulation system also includes a silicon powder packaging system, and the discharge port of the silicon powder filter is arranged corresponding to the feed port of the silicon powder packaging system.

[0026] Beneficial effects:

[0027] 1. The utility model adds a silicon powder filter, the air inlet of the silicon powder filter is connected to the air outlet port of the post-processing device through the process gas tail gas recovery main pipe, and the air outlet of the silicon powder filter is connected to the air inlet port of the granular silicon product post-processing device through the purified tail gas return pipeline, which is used to purify the process gas tail gas discharged from the post-processing device to form a process gas circulation loop. A first pressure gauge is set on the purified tail gas return pipeline to measure the pressure value of the gas in the purified tail gas return pipeline. The first pressure gauge is electrically connected to the gas main inlet valve, and the system is configured to adjust the opening of the gas main inlet valve according to the measured value of the first pressure gauge to supplement the pressure, and finally realize the recycling of process gas and reduce the consumption of process gas in the granular silicon processing process.

[0028] 2. In order to prevent part of the process gas from not meeting the standard after being filtered by the silicon powder filter, an embodiment of the present application sets an oxygen concentration detector on the purified tail gas return pipeline to measure the oxygen content value in the gas in the purified tail gas return pipeline; adds a gas vent pipeline, whose air inlet port is connected to the purified tail gas return pipeline, and sets a gas vent valve on the gas vent pipeline; the system opens and closes the gas vent valve according to the oxygen content value. When the oxygen content in the process gas circulation system meets the standard, the gas is recycled, and when the oxygen content does not meet the standard, part of the gas is vented; when the system pressure is insufficient, the pressure is supplemented through the process gas intake main pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods, and the above and / or other advantages of the present invention will become more clear.

[0030] Figure 1 A schematic diagram of a process gas circulation system for a granular silicon product post-processing device disclosed in one embodiment of the utility model.

[0031] The following are the descriptions of the reference numerals:

[0032] 1. Granular silicon product tank; 2. Screening device; 7. Product valve; 8. Dust removal device; 9. Finished product packaging system; 10. Silicon powder filter; 11. Silicon powder packaging system; 12. Circulating fan; 13. Oxygen concentration detector; 14. Gas main inlet valve; 15. Gas vent valve; 16. First process gas valve; 17. Oxygen content alarm; 18. First pressure gauge; 19. Second pressure gauge; 20. Vent control valve; 23. Third gas flow meter; 24. Fourth gas Flow meter; 31, inlet valve of screening device; 32, outlet valve of screening device; 51, inlet valve of dust removal device; 52, outlet valve of dust removal device; 100, main inlet pipe of process gas; 101, second gas flow meter; 200, main pipe for process gas tail gas recovery; 210, inlet branch pipe of dust removal device; 220, outlet branch pipe of screening device; 300, purified tail gas reflux pipeline; 400, gas venting pipeline; 810, inlet branch pipe of dust removal device; 820, outlet branch pipe of dust removal device. DETAILED DESCRIPTION

[0033] The silane fluidized bed method is used to produce granular polysilicon using a granular silicon product post-processing device for post-processing. Figure 1 The granular silicon product post-processing device includes a granular silicon product tank 1, a screening device 2, a dust removal device 8 and a finished product packaging system 9. The discharge port of the granular silicon product tank is arranged correspondingly to the feed port of the screening device 2, the discharge port of the screening device 2 is connected to the feed port of the dust removal device 8 through the product valve 7, and the feed port of the finished product packaging system is connected to the discharge port of the dust removal device 8.

[0034] During the screening and dust removal process, process gas is introduced into the screening device 2 and the dust removal device 8 of the granular silicon product post-processing device to remove silicon powder and filter dust. Specifically, for each granular silicon product post-processing device, granular silicon falls into the screening device 2 through the granular silicon product tank 1, and after screening, small particles are used in the subsequent system, and larger particles enter the dust removal device 8, and after dust removal, enter the finished product packaging system 9.

[0035] In the prior art, the process gas discharged from the granular silicon product post-processing device is directly discharged, resulting in a large amount of gas waste in the production process and increasing the gas loss in the granular silicon processing process.

[0036] In order to reduce the loss, the utility model provides a process gas circulation system for the post-processing device of granular silicon products, please refer to Figure 1 The process gas circulation system includes a process gas inlet manifold 100 , a gas manifold inlet valve 14 , a silicon powder filter 10 and a first pressure gauge 18 .

[0037] The process gas inlet manifold 100 connects the inlet port of the granular silicon product post-processing device with an external process gas source, and is used to deliver process gas from the external process gas source to the inlet port of the post-processing device;

[0038] The gas main inlet valve 14 is arranged on the process gas inlet main pipe 100, and is used to control the supply amount of the process gas source;

[0039] The silicon powder filter 10 is a metal or ceramic filter used to separate silicon powder from process gas. The air inlet of the silicon powder filter 10 is connected to the air outlet port of the post-processing device through the process gas tail gas recovery main pipe 200, and the air outlet of the silicon powder filter 10 is connected to the air inlet port of the granular silicon product post-processing device through the purified tail gas return pipeline 300, which is used to purify the process gas tail gas discharged from the post-processing device to form a process gas circulation loop.

[0040] The first pressure gauge 18 is disposed on the purified exhaust gas return pipeline 300 and is used to measure the pressure value of the gas in the purified exhaust gas return pipeline 300 .

[0041] The first pressure gauge 18 is electrically connected to the gas main inlet valve 14 , and the process gas circulation system is configured to adjust the opening of the gas main inlet valve 14 according to the measurement value of the first pressure gauge 18 to supplement the pressure.

[0042] In this embodiment, the process gas is recycled to achieve the effect of reducing gas loss.

[0043] In an embodiment, the process gas is nitrogen.

[0044] Specifically, in order to prevent part of the process gas filtered by the silicon powder filter 10 from failing to meet the standards, please refer to Figure 1 The process gas circulation system includes an oxygen concentration detector 13, a gas venting pipeline 400 and a gas venting valve 15.

[0045] The oxygen concentration detector 13 is arranged on the purified exhaust gas return pipeline 300, and is used to measure the oxygen content value in the gas in the purified exhaust gas return pipeline 300;

[0046] The air inlet port of the gas venting pipeline 400 is connected to the purified tail gas return pipeline 300, and in the process gas flow direction, the connection is located downstream of the oxygen concentration detector 13 and upstream of the connection between the process gas intake manifold 100 and the air inlet port of the post-treatment device;

[0047] The gas vent valve 15 is disposed on the gas vent pipeline 400; the process gas circulation system is configured to open and close the gas vent valve 15 according to the oxygen content value.

[0048] In this embodiment, when the oxygen content in the process gas circulation system meets the standard, the gas is recycled, and when the oxygen content does not meet the standard, part of the gas is discharged; when the system pressure is insufficient, the pressure is supplemented through the process gas intake main pipe 100.

[0049] Specifically, see Figure 1There may be more than one post-processing device for the granular silicon product, and each post-processing device for the granular silicon product includes a screening device 2 and a dust removal device 8. The air inlet of the screening device 2 is connected to an air inlet branch pipe 210 for the screening device, and the air inlet of the dust removal device 8 is connected to an air inlet branch pipe 810 for the dust removal device, and the other end of the air inlet branch pipe 210 for the screening device is connected in parallel with the other end of the air inlet branch pipe 810 for the dust removal device to the air inlet port of the post-processing device for the granular silicon product; the air outlet of the screening device 2 is connected to an air outlet branch pipe 220 for the screening device, and the air outlet of the dust removal device 8 is connected to an air outlet branch pipe 820 for the dust removal device, and the other end of the air outlet branch pipe 220 for the screening device is connected in parallel with the other end of the air outlet branch pipe 820 for the dust removal device to the air outlet port of the post-processing device for the granular silicon product.

[0050] Specifically, see Figure 1 In this embodiment, two granular silicon product post-processing devices are provided. It should be understood that there may be multiple granular silicon product post-processing devices.

[0051] For further information, see Figure 1 The system also includes a valve assembly, which is used to control more than one granular silicon product post-processing device to work one by one or simultaneously.

[0052] Specifically, see Figure 1 The valve assembly includes a screening device air inlet valve 31, a screening device air outlet valve 32, a dust removal device air inlet valve 51, a dust removal device air outlet valve 52, a third gas flowmeter 23 and a fourth gas flowmeter 24; for each granular silicon product post-processing device, the screening device air inlet valve 31 and the third gas flowmeter 23 are provided on the screening device air inlet branch 210, and the screening device air outlet valve 32 is provided on the screening device air outlet branch 220; the dust removal device air inlet valve 51 and the fourth gas flowmeter 24 are provided on the dust removal device air inlet branch 810, and the dust removal device air outlet valve 52 is provided on the dust removal device air outlet branch 820.

[0053] In this embodiment, the screening device air inlet valve 31, the screening device air outlet valve 32 and the third gas flow meter 23 are used to control the inlet and outlet pressure and flow of the screening device. The dust removal device air inlet valve 51, the dust removal device air outlet valve 52 and the fourth gas flow meter 24 are used to control the inlet and outlet pressure and flow of the dust removal device.

[0054] Specifically, see Figure 1 The process gas circulation system includes a circulation fan 12, which is used to provide power for the gas flow in the process gas circulation loop.

[0055] Specifically, see Figure 1The circulating fan 12 is disposed on the purified tail gas return pipeline 300; in the gas flow direction in the purified tail gas return pipeline 300, the circulating fan 12 is located upstream of the first pressure gauge 18. The circulating fan 12 maintains the pressure of the circulation system.

[0056] For further information, see Figure 1 The process gas circulation system further includes a silicon powder packaging system 11 , and a discharge port of the silicon powder filter 10 is arranged corresponding to a feed port of the silicon powder packaging system 11 .

[0057] Specifically, see Figure 1 The process gas circulation system includes a second gas flow meter 101, an oxygen content alarm 17, a first process gas valve 16 and a vent control valve 20. The second gas flow meter 101 is arranged on the process gas inlet manifold 100, and is used to measure the gas flow in the process gas inlet manifold 100.

[0058] The oxygen content alarm 17 is arranged on the process gas tail gas recovery main pipe 200. The first process gas valve 16 is arranged on the purified tail gas return pipeline 300, and the first process gas valve 16 is located upstream of the circulation fan 12. The vent control valve 20 is arranged at the vent port of the silicon powder filter 10.

[0059] When the oxygen content alarm 17 measures that the oxygen content in the gas in the purified tail gas return pipeline 300 exceeds 3%, the first process gas valve 16 is closed, and the vent control valve 20 and the gas main inlet valve 14 are opened to replace and purge the system, and the vent port of the silicon powder filter 10 discharges the purified process gas to the outside.

[0060] When the oxygen content alarm 17 measures that the oxygen content in the gas in the purified tail gas return pipeline 300 is lower than 3%, the vent control valve 20 is closed, the first process gas valve 16 is opened, and the system continues to circulate.

[0061] Specifically, see Figure 1 The process gas circulation system includes a second pressure gauge 19 and a third pressure gauge. The second pressure gauge 19 is arranged on the process gas tail gas recovery main pipe 200. The outlet of the silicon powder filter 10 is provided with a third pressure gauge. The pressure difference between the air inlet and the air outlet of the silicon powder filter 10 is obtained by the second pressure gauge 19 and the third pressure gauge to monitor whether the silicon powder filter 10 is damaged. The third pressure gauge is not shown in the figure.

[0062] The utility model provides a thought and method for a process gas circulation system of a granular silicon product post-processing device. There are many methods and ways to implement the technical solution. The above is only a preferred embodiment of the utility model. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the utility model. These improvements and modifications should also be regarded as the protection scope of the utility model. All components not specified in this embodiment can be implemented by existing technologies.

Claims

1. A process gas circulation system for a granular silicon product post-processing device, characterized in that: The process gas circulation system includes: A process gas inlet main pipe (100) is connected to the inlet port of the granular silicon product post-processing device and an external process gas source, and is used to transport process gas from the external process gas source to the inlet port of the post-processing device; A gas main inlet valve (14), arranged on the process gas inlet main pipe (100), for controlling the supply amount of the process gas source; A silicon powder filter (10), wherein the air inlet of the silicon powder filter (10) is connected to the air outlet port of the post-processing device via a process gas tail gas recovery main pipe (200), and the air outlet of the silicon powder filter (10) is connected to the air inlet port of the granular silicon product post-processing device via a purified tail gas return pipe (300), and is used to purify the process gas tail gas discharged from the post-processing device to form a process gas circulation loop; and a first pressure gauge (18), arranged on the purified tail gas return pipeline (300), for measuring the pressure value of the gas in the purified tail gas return pipeline (300); The first pressure gauge (18) is electrically connected to the gas main inlet valve (14), and the process gas circulation system is configured to adjust the opening of the gas main inlet valve (14) according to the measurement value of the first pressure gauge (18) to supplement the pressure.

2. The process gas circulation system for a granular silicon product post-processing device according to claim 1, characterized in that: The process gas circulation system includes: an oxygen concentration detector (13), arranged on the purified tail gas return pipeline (300), and used for measuring the oxygen content value in the gas in the purified tail gas return pipeline (300); a gas venting pipeline (400), the air inlet port of which is connected to the purified tail gas return pipeline (300), and in the process gas flow direction, the connection point is located downstream of the oxygen concentration detector (13) and upstream of the connection point between the process gas intake manifold (100) and the air inlet port of the post-treatment device; and a gas venting valve (15) disposed on the gas venting pipeline (400); the process gas circulation system is configured to open and close the gas venting valve (15) according to the oxygen content value.

3. The process gas circulation system for a granular silicon product post-processing device according to claim 2, characterized in that: There is more than one granular silicon product post-processing device, and each of the granular silicon product post-processing devices includes a screening device (2) and a dust removal device (8), the air inlet of the screening device (2) is connected to an air inlet branch pipe (210) of the screening device, the air inlet of the dust removal device (8) is connected to an air inlet branch pipe (810) of the dust removal device, and the other end of the air inlet branch pipe (210) of the screening device is connected in parallel with the other end of the air inlet branch pipe (810) of the dust removal device to the air inlet port of the granular silicon product post-processing device; the air outlet of the screening device (2) is connected to an air outlet branch pipe (220) of the screening device, the air outlet of the dust removal device (8) is connected to an air outlet branch pipe (820) of the dust removal device, and the other end of the air outlet branch pipe (220) of the screening device is connected in parallel with the other end of the air outlet branch pipe (820) of the dust removal device to the air outlet port of the granular silicon product post-processing device.

4. The process gas circulation system for a granular silicon product post-processing device according to claim 3, characterized in that: The system also includes a valve assembly, which is used to control more than one of the granular silicon product post-processing devices to work selectively or simultaneously.

5. The process gas circulation system for a granular silicon product post-processing device according to claim 4, characterized in that: The valve assembly comprises an air inlet valve (31) of a screening device, an air outlet valve (32) of a screening device, an air inlet valve (51) of a dust removal device, an air outlet valve (52) of a dust removal device, a third gas flow meter (23) and a fourth gas flow meter (24); for each of the granular silicon product post-processing devices, the air inlet valve (31) of the screening device and the third gas flow meter (23) are arranged on the air inlet branch pipe (210) of the screening device, and the air outlet valve (32) of the screening device is arranged on the air outlet branch pipe (220) of the screening device; the air inlet valve (51) of the dust removal device and the fourth gas flow meter (24) are arranged on the air inlet branch pipe (810) of the dust removal device, and the air outlet valve (52) of the dust removal device is arranged on the air outlet branch pipe (820) of the dust removal device.

6. The process gas circulation system for a granular silicon product post-processing device according to claim 5, characterized in that: The process gas circulation system comprises a circulation fan (12), wherein the circulation fan (12) is used to provide power for the gas flow in the process gas circulation loop.

7. The process gas circulation system for a granular silicon product post-processing device according to claim 6, characterized in that: The circulating fan (12) is arranged on the purified exhaust gas return pipeline (300); in the gas flow direction in the purified exhaust gas return pipeline (300), the circulating fan (12) is located upstream of the first pressure gauge (18).

8. The process gas circulation system for a granular silicon product post-processing device according to claim 7, characterized in that: The process gas circulation system includes: a second gas flow meter (101) disposed on the process gas inlet main pipe (100); an oxygen content alarm (17) disposed on the process gas tail gas recovery main pipe (200); a first process gas valve (16) disposed on the purified tail gas return pipeline (300), wherein the first process gas valve (16) is located upstream of the circulation fan (12); And a vent control valve (20) arranged at the vent port of the silicon powder filter (10).

9. The process gas circulation system for a granular silicon product post-processing device according to claim 8, characterized in that: The process gas circulation system further comprises a second pressure gauge (19) arranged on the process gas tail gas recovery main pipe (200).

10. The process gas circulation system for a granular silicon product post-processing device according to claim 1, characterized in that: The process gas circulation system also includes a silicon powder packaging system (11), and the discharge port of the silicon powder filter (10) is arranged corresponding to the feed port of the silicon powder packaging system (11).

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