Polycrystalline silicon waste gas treatment device

Abstract

The utility model provides a polycrystalline silicon waste gas treatment device and relates to the technical field of polycrystalline silicon. A water inlet pipe is arranged in the venturi tube, an air inlet pipe is communicated with the venturi tube, a cleaning assembly is arranged on the venturi tube, the top end of the water inlet pipe is connected with the top end of the venturi tube in a sealed mode, the air inlet pipe is arranged on the portion, on the outer side of the water inlet pipe, of the venturi tube, and the cleaning assembly comprises a plurality of cleaning spray heads communicated with the venturi tube. And the cleaning nozzle injects cleaning liquid into the Venturi tube. According to the utility model, the Venturi tube does not need to be disassembled during unblocking.

Description

Technical Field

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

[0002] In the domestic production of polysilicon, most manufacturers use the "modified Siemens method" to react hydrogen chloride with industrial silicon powder, and finally obtain polysilicon with higher purity after distillation, purification, reduction and other processes. When treating the waste gas generated in the production of polysilicon, the waste gas contains a large amount of hydrogen chloride, chlorosilane, hydrogen and a small amount of silicon powder and other substances. In the existing technology, some Venturi devices are used for waste gas absorption. The device uses a double-pass interface, one end of which is connected to high-pressure water flow and the other end of which is connected to waste gas. Because the diameter of the pipe changes from coarse to fine at the throat, the mixing of waste gas and water is accelerated to achieve the purpose of treating waste gas.

[0003] In the polysilicon production industry, the exhaust gas contains a large amount of substances such as hydrogen chloride and chlorosilane. Chlorosilane will undergo a hydrolysis reaction when it comes into contact with water, and the resulting solids such as water-insoluble silicic acid and methyl silicate that are not easily soluble in liquids will adhere to the wall of the venturi tube, causing pipe blockage and obstruction of the passage of the venturi tube. The exhaust gas cannot be treated normally and requires frequent and scheduled disassembly and cleaning. The cleaning operation increases the safety risk of open-loop operations for personnel, and the device needs to be frequently switched for start-up and shutdown operations, which cannot achieve stable operation of the process over a long period of time. Utility Model Content

[0004] The utility model aims to develop a polysilicon waste gas treatment device which does not require the venturi tube to be disassembled when clearing blockage.

[0005] The utility model is achieved through the following technical solutions:

[0006] A polysilicon waste gas treatment device, comprising:

[0007] Venturi tube;

[0008] A water inlet pipe is arranged in the venturi tube;

[0009] An air inlet pipe connected to the venturi tube;

[0010] A cleaning assembly is provided on the venturi tube;

[0011] Among them, the top end of the water inlet pipe is sealed and connected to the top end of the venturi tube, the air inlet pipe is arranged on the venturi tube outside the water inlet pipe, and the cleaning component includes a plurality of cleaning nozzles connected to the venturi tube, and the cleaning nozzles inject cleaning liquid into the venturi tube.

[0012] Optionally, the Venturi tube includes, from top to bottom, a cylindrical first inlet section, a truncated cone-shaped first contraction section, a throat and a truncated cone-shaped diffusion section.

[0013] Optionally, the water inlet pipe is arranged in the first inlet section of the venturi tube and is coaxial therewith, and the water inlet pipe includes a second inlet section and a second contraction section from top to bottom, and the shapes of the second inlet section and the second contraction section are adapted to the first inlet section and the first contraction section. The bottom end of the second contraction section extends above the throat, and the top end of the second inlet section of the water inlet pipe is connected to the top flange of the first inlet section of the venturi tube.

[0014] Optionally, the water inlet pipe and the cleaning nozzle are arranged on the first inlet section of the Venturi tube.

[0015] Optionally, the cleaning assembly further comprises a plurality of reserved tubes arranged on the outer wall of the first inlet section, the ends of the reserved tubes are provided with pipe joint nuts, and the cleaning nozzle is arranged in the reserved tubes and threadedly connected to the pipe joint nuts.

[0016] Optionally, a plurality of the reserved tubes are arranged at equal intervals in the same circumferential direction on the first inlet section, and the reserved tubes are arranged along the radial direction of the first inlet section.

[0017] Optionally, the inner end of the cleaning nozzle extends into the gap between the first inlet section and the second inlet section, the liquid outlet of the inner end of the cleaning nozzle is inclined downward toward the gap between the first contraction section and the second contraction section, the outer end of the cleaning nozzle is connected to a cleaning pipeline, and the cleaning liquid enters through the cleaning pipeline.

[0018] Optionally, the cleaning liquid may be water, an acidic liquid or an alkaline liquid, and fine sand may be added to the cleaning liquid.

[0019] Optionally, a monitoring component is further provided in the venturi tube, and the monitoring component includes a reflective photoelectric sensor provided on the outer wall of the inner end of the cleaning nozzle.

[0020] The beneficial effects of the utility model are:

[0021] When the utility model detects that the inside of the venturi tube is blocked, the inside of the venturi tube is automatically flushed by high-pressure cleaning liquid, thereby realizing automatic clearing of blockage. There is no need to disassemble the venturi tube for cleaning, and the device does not need to be frequently switched to start and stop operations, thus realizing stable operation of the process over a long period of time. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It is a structural schematic diagram of the utility model;

[0024] Figure 2 It is a schematic diagram of the structure of the cleaning component;

[0025] Figure 3 Schematic diagram of the intake pipe structure.

[0026] Figure numerals: 100, Venturi tube; 101, first inlet section; 102, first contraction section; 103, throat; 104, diffusion section; 200, air inlet pipe; 300, cleaning component; 301, reserved pipe; 302, cleaning nozzle; 303, pipe joint nut; 400, water inlet pipe; 401, second inlet section; 402, second contraction section; 500, monitoring component; 501, reflective photoelectric sensor; 502, control circuit. DETAILED DESCRIPTION

[0027] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0028] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation to the present invention.

[0029] The embodiments of the present utility model are described in detail below with reference to the accompanying drawings.

[0030] like Figures 1 to 3As shown, the utility model discloses a polysilicon waste gas treatment device, including a venturi tube 100, which includes a cylindrical first inlet section 101, a truncated cone-shaped first contraction section 102, a throat 103 and a truncated cone-shaped diffusion section 104 from top to bottom.

[0031] The first inlet section 101 of the venturi tube 100 is provided with a water inlet pipe 400 in a coaxial state therewith, and the water inlet pipe 400 includes a second inlet section 401 and a second contraction section 402 from top to bottom, and the shapes of the second inlet section 401 and the second contraction section 402 are adapted to the first inlet section 101 and the first contraction section 102, and the bottom end of the second contraction section 402 extends above the throat 103. The top end of the second inlet section 401 of the water inlet pipe 400 is connected to the top end flange of the first inlet section 101 of the venturi tube 100.

[0032] An air intake pipe 200 is provided on the outer wall of the first inlet section 101 of the venturi tube 100. The exhaust gas enters the first inlet section 101 of the venturi tube 100 through the air intake pipe 200 and then enters the first contraction section 102 downward. The high-pressure water flow enters from the second inlet section 401 of the water inlet pipe 400 and then enters the second contraction section 402 downward. The exhaust gas and the high-pressure water flow are mixed at the throat 103 and output from the diffusion section 104, thereby achieving the purpose of exhaust gas treatment.

[0033] The venturi tube 100 is provided with a cleaning assembly 300, which cleans the water-insoluble solid dirt attached to the inner wall of the venturi tube 100. The cleaning assembly 300 includes four reserved tubes 301 arranged on the first inlet section 101, and the four reserved tubes 301 are arranged at equal intervals in the same circumferential direction of the first inlet section 101, and the reserved tubes 301 are arranged along the radial direction of the first inlet section 101.

[0034] The end of the reserved pipe 301 away from the venturi tube 100 is provided with a pipe joint nut 303, and a cleaning nozzle 302 threadedly connected to the pipe joint nut 303 is provided in the reserved pipe 301. The inner end of the cleaning nozzle 302 extends into the gap between the first inlet section 101 and the second inlet section 401, and the liquid outlet of the inner end of the cleaning nozzle 302 is inclined downward toward the gap between the first contraction section 102 and the second contraction section 402. The outer end of the cleaning nozzle 302 is connected to a cleaning pipeline, and the cleaning pipeline inputs high-pressure cleaning liquid to the cleaning nozzle 302. The high-pressure cleaning liquid is finally sprayed from the inner end of the cleaning nozzle 302 to wash the inner wall of the first contraction section 102, the outer wall of the second contraction section 402 and the throat 103. The cleaning liquid can be water, and the pH value of the cleaning liquid can also be adjusted according to the properties of the solid dirt, or fine sand can be added to the cleaning liquid.

[0035] A monitoring component 500 is also provided in the venturi tube 100. The monitoring component 500 monitors the blockage condition in the venturi tube 100. The cleaning component 300 automatically performs a cleaning operation according to the blockage condition. The monitoring component 500 includes a reflective photoelectric sensor 501 provided on the outer wall of the inner end of the cleaning nozzle 302. The reflective photoelectric sensor 501 monitors the attachment condition of solid dirt on the outer wall of the second inlet section 401. The control circuit 502 of the reflective photoelectric sensor 501 extends from the cleaning nozzle 302 to the outside of the venturi tube 100 and is electrically connected to a controller (not shown in the figure). A solenoid valve (not shown in the figure) electrically connected to the controller can be provided on the cleaning nozzle 302 or the cleaning pipeline, and the controller is also electrically connected to a driving source (which can be a pump) of a high-pressure cleaning liquid. When a lot of solid dirt adheres to the outer wall of the second inlet section 401 and affects the photoelectric signal received by the reflective photoelectric sensor 501 through reflection, the electrical signal of the reflective photoelectric sensor 501 is transmitted to the controller, and the controller drives the solenoid valve to open, and the driving source of the high-pressure cleaning liquid starts to operate, so that the high-pressure cleaning liquid is sprayed out from the cleaning pipeline and the high-pressure nozzle to flush the inside of the Venturi tube 100.

[0036] When the utility model detects that the inside of the venturi tube 100 is blocked, the inside of the venturi tube 100 is automatically flushed by high-pressure cleaning liquid, thereby automatically clearing the blockage. There is no need to disassemble the venturi tube 100 for cleaning, and the device does not need to be frequently switched to start and stop operations, thereby achieving stable operation of the process over a long period of time.

[0037] The above embodiments are only preferred embodiments of the present utility model and are not limitations on the technical solutions of the present utility model. Any technical solution that can be implemented on the basis of the above embodiments without creative work should be deemed to fall within the scope of protection of the patent of the present utility model.

Claims

1. A polysilicon waste gas treatment device, characterized in that: include: Venturi tube; A water inlet pipe is arranged in the venturi tube; An air inlet pipe connected to the venturi tube; A cleaning assembly is provided on the venturi tube; Among them, the top end of the water inlet pipe is sealed and connected to the top end of the venturi tube, the air inlet pipe is arranged on the venturi tube outside the water inlet pipe, and the cleaning component includes a plurality of cleaning nozzles connected to the venturi tube, and the cleaning nozzles inject cleaning liquid into the venturi tube.

2. The polysilicon waste gas treatment device according to claim 1, characterized in that: The venturi tube includes, from top to bottom, a cylindrical first inlet section, a truncated cone-shaped first contraction section, a throat and a truncated cone-shaped diffusion section.

3. The polysilicon waste gas treatment device according to claim 2, characterized in that: The water inlet pipe is arranged in the first inlet section of the venturi tube and is coaxial therewith. The water inlet pipe includes a second inlet section and a second contraction section from top to bottom. The shapes of the second inlet section and the second contraction section are adapted to the first inlet section and the first contraction section. The bottom end of the second contraction section extends above the throat, and the top end of the second inlet section of the water inlet pipe is connected to the top flange of the first inlet section of the venturi tube.

4. The polysilicon waste gas treatment device according to claim 2, characterized in that: The water inlet pipe and the cleaning nozzle are arranged on the first inlet section of the venturi tube.

5. The polysilicon waste gas treatment device according to claim 2, characterized in that: The cleaning assembly also includes a plurality of reserved tubes arranged on the outer wall of the first inlet section, the ends of the reserved tubes are provided with pipe joint nuts, and the cleaning nozzles are arranged in the reserved tubes and are threadedly connected with the pipe joint nuts.

6. The polysilicon waste gas treatment device according to claim 5, characterized in that: The plurality of reserved tubes are arranged at equal intervals in the same circumferential direction on the first inlet section, and the reserved tubes are arranged along the radial direction of the first inlet section.

7. The polysilicon waste gas treatment device according to claim 3, characterized in that: The inner end of the cleaning nozzle extends into the gap between the first inlet section and the second inlet section, the liquid outlet of the inner end of the cleaning nozzle is inclined downward toward the gap between the first contraction section and the second contraction section, the outer end of the cleaning nozzle is connected to a cleaning pipeline, and the cleaning liquid enters through the cleaning pipeline.

8. The polysilicon waste gas treatment device according to claim 1, characterized in that: The cleaning liquid may be water, an acidic liquid or an alkaline liquid, and fine sand may be added to the cleaning liquid.

9. The polysilicon waste gas treatment device according to claim 1, characterized in that: A monitoring component is also provided in the venturi tube, and the monitoring component includes a reflective photoelectric sensor provided on the outer wall of the inner end of the cleaning nozzle.

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