Silicon powder conveying system

Abstract

The utility model provides a silicon powder conveying system, and relates to the technical field of silicon powder conveying. The device comprises a stock bin, a feeding device, a feeding device, a pneumatic conveying device and a tail gas treatment device, the feeding device comprises a plurality of feeding units, each feeding unit comprises a silicon powder sending tank and a silicon powder receiving tank which are communicated through a pipeline, the silicon powder sending tanks are located below the stock bin and communicated with the bottom of the stock bin through a pipeline, and the silicon powder receiving tanks are communicated with the tail gas treatment device. The silicon powder sending tank is further communicated with a side pipeline of the stock bin, the pneumatic conveying device comprises a nitrogen storage tank, a silicon powder sending pipe set communicated with the feeding unit is arranged on the nitrogen storage tank, the tail gas treatment device comprises a silicon powder filter, a first buffer tank, a filtering mechanism, a compressor and a second buffer tank which are communicated in sequence, and the silicon powder filter is communicated with the silicon powder receiving tank. And the second buffer tank is communicated with a nitrogen storage tank. The silicon powder conveying efficiency is greatly improved, and the labor intensity of workers is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of silicon powder conveying, and particularly relates to a silicon powder conveying system. Background Art

[0002] In the polysilicon cold hydrogenation synthesis process, silicon powder is an important raw material. At present, the feeding of silicon powder is generally carried out manually, which not only has low operation efficiency, large manual labor intensity, but also has poor conveying efficiency and continuity. Summary of the Utility Model

[0003] The purpose of the utility model is to develop a silicon powder conveying system that can greatly improve the conveying efficiency of silicon powder and reduce the manual labor intensity.

[0004] The utility model is realized by the following technical solutions:

[0005] A silicon powder conveying system includes:

[0006] A silo, a feeding device, a material conveying device, a pneumatic conveying device and a tail gas treatment device;

[0007] Among them, the material conveying device includes multiple groups of material conveying units. Each material conveying unit includes a silicon powder sending tank and a silicon powder receiving tank connected by a pipeline. The silicon powder sending tank is located below the silo, and the silicon powder sending tank is connected to the bottom of the silo by a pipeline. The silicon powder sending tank is also connected to the side of the silo by a pipeline;

[0008] The pneumatic conveying device includes a nitrogen storage tank, and a silicon powder sending pipe group connected to the material conveying unit is arranged on the nitrogen storage tank;

[0009] The tail gas treatment device includes a silicon powder filter, a first buffer tank, a filtering mechanism, a compressor and a second buffer tank connected in sequence. The silicon powder filter is connected to the silicon powder receiving tank, and the second buffer tank is connected to the nitrogen storage tank.

[0010] Optionally, a manhole and a dust remover on the top of the silo are provided. A centrifugal fan is arranged on the dust remover on the top of the silo, and a first air conveying pipe connected to the dust remover on the top of the silo is communicated on the nitrogen storage tank.

[0011] Optionally, the feeding device includes a bucket elevator arranged on the side of the silo and a feeding pipe arranged on the top of the silo. The feeding pipe is connected to a tank truck for transporting silicon powder, and a second air conveying pipe connected to the tank truck is communicated on the nitrogen storage tank.

[0012] Optionally, the silicon powder sending pipe group includes three pipelines, and the three pipelines are respectively connected to the side and bottom of the silicon powder sending tank and the pipeline between the silicon powder sending tank and the silicon powder receiving tank.

[0013] Optionally, a catalyst feeding device connected to the above-mentioned silicon powder sending tank through a pipeline is further provided above the silicon powder sending tank, and the catalyst feeding device is a screw conveyor.

[0014] Optionally, the silicon powder filter is arranged above the silicon powder receiving tank, and an exhaust pipe and a return pipe are connected between the silicon powder filter and the top of the silicon powder receiving tank.

[0015] Optionally, a vent pipe is provided on the first buffer tank, and an online hydrogen and oxygen content analyzer and a vent valve are sequentially arranged on the vent pipe. The online hydrogen and oxygen content analyzer is connected to the vent pipe through a pipeline and a ball valve is arranged on the pipeline. The online hydrogen and oxygen content analyzer and the vent valve are interlocked for control.

[0016] Optionally, the filtering mechanism includes two nitrogen filters arranged in parallel. The inlet ends of the two nitrogen filters are both connected to the outlet pipe of the first buffer tank, and the outlet ends of the two nitrogen filters are both connected to the inlet pipe of the compressor. Valves are correspondingly arranged on the inlet ends and the outlet ends of the two nitrogen filters.

[0017] Optionally, the nitrogen filter includes a tank body. A partition is arranged in the tank body. The inlet end and the outlet end of the tank body are respectively below and above the partition. A plurality of filter elements are arranged on the partition. The filter elements are vertically arranged in a matrix, and the filter elements are powder sintered filter elements.

[0018] Optionally, the second buffer tank is connected to the first buffer tank.

[0019] The beneficial effects of the present utility model are as follows:

[0020] The present utility model greatly improves the feeding efficiency of silicon materials through pneumatic conveying. By setting up a tail gas treatment device, the nitrogen gas used in pneumatic conveying can be filtered and reused, avoiding waste caused by the external discharge of nitrogen gas and improving economic benefits. Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0022] Figure 1 It is a structural diagram of the present utility model;

[0023] Figure 2 It is an internal structural diagram of the nitrogen filter.

[0024] Reference numerals: 1, silo; 2, dust collector on top of the silo; 3, bucket elevator; 4, tank truck; 5, feeding pipe; 6, nitrogen storage tank; 7, silicon powder sending tank; 8, catalyst feeding equipment; 9, first gas transmission pipe; 10, second gas transmission pipe; 11, silicon powder sending pipe group; 12, silicon powder receiving tank; 13, silicon powder filter; 14, first buffer tank; 15, vent pipe; 16, nitrogen filter; 161, partition board; 162, filter element; 17, compressor; 18, second buffer tank. Detailed implementation manners

[0025] In the following text, only some exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the present invention. Therefore, the drawings and the description are considered to be exemplary in nature rather than restrictive.

[0026] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, the meaning of "a plurality" is two or more unless otherwise specifically defined.

[0027] The embodiments of the present utility model will be described in detail below with reference to the drawings.

[0028] As Figure 1 and Figure 2 shown, the present utility model discloses a silicon powder conveying system, which includes a silo 1, a feeding device, a feeding device, a pneumatic conveying device and a tail gas treatment device. The feeding device sends silicon powder to the silo 1, the silicon powder in the silo 1 is sent to the hydrogenation furnace by the feeding device, part of the silicon powder is conveyed by the pneumatic conveying device during the conveying process, and the tail gas treatment device treats and recycles the tail gas generated by the pneumatic conveying.

[0029] The silo 1 is located at a high place. A manhole and a dust collector 2 on top of the silo are provided at the top of the silo 1, and a centrifugal fan is provided on the dust collector 2 on top of the silo.

[0030] The feeding device includes a bucket elevator 3 provided on the side of the silo 1. The bagged silicon powder is manually forklifted to the bucket elevator 3, and after manually opening the bag, the silicon powder is placed in the bucket elevator 3, and the bucket elevator 3 feeds the silicon powder into the silo 1.

[0031] The feeding device further includes a feeding pipe 5 provided on the top of the silo 1. A manual ball valve is provided on the feeding pipe 5, and the feeding pipe 5 is connected to the tank truck 4 for transporting silicon powder. The silicon powder in the tank truck 4 is sent into the silo 1 through the feeding pipe 5.

[0032] The feeding device includes multiple groups of feeding units. In this embodiment, the number of feeding units is three. The feeding unit includes a silicon powder sending tank 7 and a silicon powder receiving tank 12 that are connected by pipelines. The silicon powder sending tank 7 is located below the silo 1. The silicon powder sending tank 7 is connected to the bottom of the silo 1 by a pipeline, and the silicon powder sending tank 7 is also connected to the side of the silo 1 by a pipeline. Above the silicon powder sending tank 7, there is also a catalyst feeding device 8 connected to it by a pipeline. The catalyst feeding device 8 is a screw conveyor, and the catalyst can be added to the silicon powder sending tank 7 through this.

[0033] The pneumatic conveying device includes a nitrogen storage tank 6. An inlet pipe is connected to the nitrogen storage tank 6, and compressed nitrogen at 0.6 Mpa is sent into the nitrogen storage tank 6 through the inlet pipe.

[0034] A first gas transmission pipe 9 is connected to the nitrogen storage tank 6. The first gas transmission pipe 9 is connected to the bag filter on top of the silo 2. The first gas transmission pipe 9 inputs nitrogen into the bag filter on top of the silo 2 as the jetting gas source to blow the silicon powder filtered by the bag filter on top of the silo 2 into the silo 1.

[0035] A second gas transmission pipe 10 is connected to the nitrogen storage tank 6. The second gas transmission pipe 10 is connected to the tank truck 4. The second gas transmission pipe 10 sends the gas source into the tank truck 4 to realize the pneumatic conveying of the silicon powder in the tank truck 4. The silicon powder in the tank truck 4 is pneumatically conveyed into the silo 1 through the feeding pipe 5.

[0036] The nitrogen storage tank 6 is connected to a silicon powder sending pipe group 11 that is connected to the feeding unit. The silicon powder sending pipe group 11 includes three pipelines, which are respectively connected to the side and bottom of the silicon powder sending tank 7 and the pipeline between the silicon powder sending tank 7 and the silicon powder receiving tank 12. The compressed nitrogen conveyed through the silicon powder sending pipe group 11 sends the silicon powder in the silicon powder sending tank 7 to the silicon powder receiving tank 12.

[0037] The tail gas treatment device includes a silicon powder filter 13, a first buffer tank 14, a filtering mechanism, a compressor 17, and a second buffer tank 18 that are connected in sequence. The number of silicon powder filters 13 matches the number of feeding units. A silicon powder filter 13 is connected to each silicon powder receiving tank 12. An exhaust pipe and a return pipe are connected between the silicon powder filter 13 and the top of the silicon powder receiving tank 12.

[0038] The silicon powder filter 13 is connected to the first buffer tank 14. The nitrogen discharged from the silicon powder receiving tank 12 through the exhaust pipe is preliminarily filtered by the silicon powder filter 13 and then input into the first buffer tank 14. A vent pipe 15 is provided on the first buffer tank 14. An online hydrogen and oxygen content analyzer and a vent valve are sequentially provided on the vent pipe 15. The online hydrogen and oxygen content analyzer is connected to the vent pipe 15 by a pipeline and a ball valve is provided on the pipeline. The online hydrogen and oxygen content analyzer and the vent valve are interlocked for control. When the online hydrogen and oxygen content analyzer monitors that the hydrogen and oxygen content in the first buffer tank 14 is abnormal, the vent valve opens to make the vent pipe 15 vent.

[0039] The filtering mechanism includes two nitrogen filters 16 which are arranged in parallel. The inlet ends of the two nitrogen filters 16 are both communicated with the outlet pipe of the first buffer tank 14, and the outlet ends of the two nitrogen filters 16 are both communicated with the inlet pipe of the compressor 17. Valves are correspondingly arranged on the inlet ends and the outlet ends of the two nitrogen filters 16.

[0040] When the filtering mechanism works, the nitrogen gas output by the first buffer tank 14 passes through one of the nitrogen filters 16 for filtering and then enters the compressor 17, and the other nitrogen filter 16 stops working and can be used as a spare or for maintenance.

[0041] The nitrogen filter 16 includes a tank body. A partition plate 161 is arranged in the tank body. The inlet end of the tank body is below the partition plate 161, and the outlet end of the tank body is above the partition plate 161. A plurality of filter elements 162 arranged in a matrix are provided on the partition plate 161. The filter elements 162 are vertically arranged in the tank body, and the filter elements 162 are powder sintered filter elements. After the nitrogen gas enters the tank body from the inlet end of the tank body, it enters the filter elements 162 for filtering, and then passes through the partition plate 161 and is output from the outlet end of the tank body.

[0042] The nitrogen gas output by the compressor 17 enters the second buffer tank 18, and the nitrogen gas output by the second buffer tank 18 enters the nitrogen storage tank 6 for reuse. The second buffer tank 18 is also communicated with the first buffer tank 14, so that the nitrogen gas can flow back to the first buffer tank 14 for cyclic filtering.

[0043] Part of the bagged silicon powder is fed into the silo 1 by the bucket elevator 3, and part of the silicon powder is fed into the silo 1 by the tank truck 4 through pneumatic conveying. The baghouse dust collector 2 at the top of the silo 1 performs in-silo dust removal. The silicon powder in the silo 1 is fed into the silicon powder sending tanks 7 of the three feeding units. The catalyst is added into the silicon powder sending tanks 7 by the catalyst feeding equipment 8. The materials in the silicon powder sending tanks 7 are pneumatically conveyed by the compressed nitrogen gas ejected from the silicon powder sending pipe group 11. After the silicon powder is pneumatically conveyed to the silicon powder receiving tank 12, the silicon powder receiving tank 12 heats the silicon powder and then sends it to the hydrogenation furnace. The nitrogen gas entering the silicon powder receiving tank 12 together with the silicon powder enters the silicon powder filter 13 for preliminary filtering. The silicon powder filtered by the silicon powder filter 13 falls back into the silicon powder receiving tank 12 through the return pipe. The pressure of the nitrogen gas after preliminary filtering is about 30Kpa. After the nitrogen gas enters the first buffer tank 14 for pressure stabilization, it then passes through one of the nitrogen filters 16 of the filtering mechanism to complete secondary filtering. The nitrogen gas after secondary filtering is pressurized to 0.6Mpa by the compressor 17 and then sent into the second buffer tank 18. The nitrogen gas in the second buffer tank 18 is then sent into the nitrogen storage tank 6 for reuse.

[0044] The utility model greatly improves the feeding efficiency of silicon materials through pneumatic conveying, sets up a tail gas treatment device, can filter and reuse the nitrogen gas for pneumatic conveying, avoids waste caused by nitrogen gas discharge, and improves economic benefits.

[0045] The above embodiments are only the preferred embodiments of the present invention, and do not limit the technical solutions of the present invention. Any technical solution that can be achieved on the basis of the above embodiments without creative work shall be regarded as falling within the scope of the protection of the present invention patent.

Claims

1. A silicon powder conveying system, characterized in that: include: Silos, loading devices, feeding devices, pneumatic conveying devices and tail gas treatment devices; The feeding device includes a plurality of feeding units, and the feeding unit includes a silicon powder sending tank and a silicon powder receiving tank connected by pipelines. The silicon powder sending tank is located below the silo, and the silicon powder sending tank is connected to the pipeline at the bottom of the silo, and the silicon powder sending tank is also connected to the pipeline on the side of the silo; The pneumatic conveying device comprises a nitrogen storage tank, and the nitrogen storage tank is provided with a silicon powder sending pipe group connected with the feeding unit; The tail gas treatment device comprises a silicon powder filter, a first buffer tank, a filtering mechanism, a compressor and a second buffer tank which are connected in sequence. The silicon powder filter is connected to a silicon powder receiving tank, and the second buffer tank is connected to a nitrogen storage tank.

2. The silicon powder conveying system according to claim 1, characterized in that: The top of the silo is provided with a manhole and a silo top dust collector, the silo top dust collector is provided with a centrifugal fan, and the nitrogen storage tank is connected to a first air supply pipe connected to the silo top dust collector.

3. The silicon powder conveying system according to claim 1, characterized in that: The feeding device includes a bucket elevator arranged on the side of the silo and a feeding pipe arranged on the top of the silo, the feeding pipe is connected to a tank truck for transporting silicon powder, and the nitrogen storage tank is connected to a second gas pipeline connected to the tank truck.

4. The silicon powder conveying system according to claim 1, characterized in that: The silicon powder sending pipe group includes three pipelines, and the three pipelines are respectively connected with the side and bottom of the silicon powder sending tank and the pipeline between the silicon powder sending tank and the silicon powder receiving tank.

5. The silicon powder conveying system according to claim 1, characterized in that: A catalyst feeding device connected to a pipeline of the silicon powder sending tank is arranged above the silicon powder sending tank, and the catalyst feeding device is a screw conveyor.

6. The silicon powder conveying system according to claim 1, characterized in that: The silicon powder filter is arranged above the silicon powder receiving tank, and an exhaust pipe and a return pipe are connected between the silicon powder filter and the top of the silicon powder receiving tank.

7. The silicon powder conveying system according to claim 1, characterized in that: The first buffer tank is provided with a vent pipe, on which an online hydrogen and oxygen content analyzer and a vent valve are sequentially provided. The online hydrogen and oxygen content analyzer is connected to the vent pipe and a ball valve is provided on the pipe. The online hydrogen and oxygen content analyzer is interlocked with the vent valve for control.

8. The silicon powder conveying system according to claim 1, characterized in that: The filtering mechanism comprises two nitrogen filters arranged in parallel, the inlet ends of the two nitrogen filters are both connected to the outlet pipe of the first buffer tank, the outlet ends of the two nitrogen filters are both connected to the inlet pipe of the compressor, and valves are correspondingly provided on the inlet ends and outlet ends of the two nitrogen filters.

9. The silicon powder conveying system according to claim 8, characterized in that: The nitrogen filter comprises a tank body, a partition is arranged in the tank body, the inlet end and the outlet end of the tank body are respectively located below and above the partition, a plurality of filter elements are arranged vertically in a matrix, and the filter elements are powder sintered filter elements.

10. The silicon powder conveying system according to claim 1, characterized in that: The second buffer tank is communicated with the first buffer tank.

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