A high-boiling material treatment system in high-crystalline silicon production
Patent Information
- Application Number
- CN202620072970.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-20
- Publication Date
- 2026-10-20
- Estimated Expiration
- 2036-01-20
AI Technical Summary
[0004]上述工艺主要存在如下问题：（1）尾气回收和氢化系统高沸经真空转鼓过滤、提浓、再过滤、裂解、分离工艺流程，过于繁琐，存在能耗浪费
[0021]（1）本系统通过优化高沸处理流程：高沸来料→精密过滤器→提浓塔→提浓塔塔釜泵→塔釜采出冷却器→高沸进料缓冲罐→反应釜→精馏塔，液相氯硅烷经吸附柱除杂（主要B、P杂质）后送至氢化系统储罐，极大降低对下游品质影响。
Smart Images
Figure CN224864939U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of polycrystalline silicon production systems, specifically relating to a high-boiling-point material handling system in high-crystalline silicon production. Background Technology
[0002] In the existing polysilicon production process, the high-boiling liquid (polysilane content of about 5-10%) from the tail gas recovery unit and the high-boiling liquid (polysilane content of about 5%) from hydrogenation are transported to the vacuum drum filter by the bottom pump. The filtered high-boiling liquid is then sent to the feed buffer tank of the reactor by the transfer pump.
[0003] The high-boiling clear liquid in the feed buffer tank of the reactor is pumped to the stirred reactor, and HCl is sent to the stirred reactor by a compressor. Under the action of a catalyst (mixed with silicon tetrachloride and hydrogen chloride in a certain proportion), they react to produce trichlorosilane and silicon tetrachloride. Steam is introduced into the jacket of the stirred reactor for heating. The gaseous chlorosilane and hydrogen chloride enter a high-boiling cracking distillation column for separation. The chlorosilane collected from the top of the column is sent to the hydrogenation synthesis unit.
[0004] The above process has the following main problems: (1) The process flow of high boiling point material recovery and hydrogenation system through vacuum drum filtration, concentration, re-filtration, cracking and separation is too complicated and wastes energy. (2) The concentrated high boiling point material needs to be filtered by drum. The filter residue after drum filtration is not dried thoroughly by the dryer and still contains chlorosilane. The dried residue needs to be mixed with lime powder and then treated with water. The risk factor is high and acid mist is generated, causing environmental pollution. (3) The process flow can be further optimized and adjusted to reduce energy consumption and cost, improve the safety system and reduce environmental impact. Utility Model Content
[0005] Purpose of the utility model: The technical problem to be solved by this utility model is to provide a high-boiling-point material handling system that can reduce energy consumption and cost, improve safety, and reduce environmental impact, in order to address the shortcomings of the existing technology.
[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0007] A high-boiling-point material handling system for high-crystalline silicon production includes an enrichment tower, a reaction vessel, a distillation tower, and a hydrogen chloride feeding unit;
[0008] The front end of the concentration tower is connected to the high-boiling material outlet pipe via a feed pipeline to receive the high-boiling material generated during the production of high-crystalline silicon; the bottom of the concentration tower is connected to the reactor via a pipeline to send the concentrated high-boiling material into the reactor for further reaction; the top of the concentration tower is connected to the top outlet pipe and sent to the STC main pipe.
[0009] The feed side of the reactor is also connected to the reactor extractant injection pipeline and the hydrogen chloride feeding unit. The bottom outlet is connected to the reactor external delivery pipeline, and the top is connected to the distillation column through the collection pipeline.
[0010] The distillation column is connected to the rear end of the reactor. Its bottom is connected to the distillation column bottom feed line, and its top is connected to the top feed line and the hydrogen chloride feed unit via pipelines.
[0011] Furthermore, a precision filter, a high-boiling feed buffer tank, and a concentration feed pump are sequentially installed on the feed pipeline between the high-boiling material outlet pipe and the concentration tower.
[0012] Furthermore, a high-boiling reactor feed buffer tank is connected between the concentration tower and the reactor.
[0013] Furthermore, a reboiler pump and a reboiler cooler are sequentially installed on the pipeline between the concentration tower and the feed buffer tank of the high-boiling reactor.
[0014] Furthermore, a reactor feed pump is installed on the pipeline between the high-boiling reactor feed buffer tank and the reactor.
[0015] Furthermore, the top of the concentration tower is provided with a first top reflux tank, a top extraction pump, and a first activated carbon adsorption column in sequence on the top extraction pipeline.
[0016] Furthermore, a distillation column bottom discharge pump is installed on the distillation column bottom delivery pipeline; a second top reflux tank is installed on the distillation column top pipeline, and the second top reflux tank is connected to the top discharge delivery pipeline of the coarse fractionation column and the hydrogen chloride feed unit through pipelines.
[0017] Furthermore, a top reflux pump and a second activated carbon adsorption column are sequentially installed on the pipeline between the second top reflux tank and the pipeline for sending the top product to the coarse fractionation tower.
[0018] Furthermore, a tower top cooler and a vent VG1 main pipe are installed on the pipeline between the second tower top reflux tank and the hydrogen chloride feeding unit.
[0019] Specifically, the hydrogen chloride feeding unit includes a hydrogen chloride compressor pre-buffer tank, a hydrogen chloride compressor, and a hydrogen chloride compressor post-buffer tank connected in sequence; the hydrogen chloride compressor post-buffer tank is connected to the reactor or the circulating hydrogen chloride external hydrogenation system pipeline via pipelines; the hydrogen chloride compressor pre-buffer tank is connected to the top outlet pipeline of the distillation column.
[0020] Compared with the prior art, the present invention has the following beneficial effects:
[0021] (1) This system optimizes the high-boiling process: high-boiling feed → precision filter → concentration tower → concentration tower bottom pump → tower bottom cooler → high-boiling feed buffer tank → reactor → distillation tower. Liquid chlorosilane is sent to the hydrogenation system storage tank after being removed by adsorption column (mainly B and P impurities), which greatly reduces the impact on downstream quality.
[0022] (2) The high-boiling point of this system is filtered by a precision filter and then enters the concentration tower. After further concentration, it is directly sent to the reactor without being filtered by a vacuum drum filter, which reduces production costs and energy consumption and reduces environmental impact. Attached Figure Description
[0023] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.
[0024] Figure 1 This is a schematic diagram of the overall structure of this processing system.
[0025] The reference numerals in the attached figures represent:
[0026] 0-High-boiling-point material outlet pipe; 1-Precision filter; 2-High-boiling-point feed buffer tank; 3-Concentration feed pump; 4-Concentration tower; 5-Concentration tower bottom outlet pump; 6-Top reflux tank; 7-Top outlet pump; 8-Top outlet sent to STC main pipe; 9-Bottom outlet cooler; 10-High-boiling-point reactor feed buffer tank; 11-Reactor feed pump; 12-Reactor; 13-Reactor external pipeline; 14-Distillation tower bottom outlet pump; 15-Distillation tower bottom external pipeline; 1 6-Distillation column; 17-Top reflux tank; 18-Top reflux pump; 19-Top product delivery pipeline to coarse fractionation column; 20-Top cooler; 21-Vent VG1 main pipe; 22-Hydrogen chloride gas; 23-Hydrogen chloride compressor pre-buffer tank; 24-Hydrogen chloride compressor; 25-Hydrogen chloride compressor post-buffer tank; 26-Circulating hydrogen chloride delivery pipeline to hydrogenation system; 27-Reaction vessel extractant injection pipeline; 28-First activated carbon adsorption column; 29-Second activated carbon adsorption column. Detailed Implementation
[0027] The present invention can be better understood from the following embodiments.
[0028] The structures, proportions, and sizes shown in the accompanying drawings are merely for illustrative purposes and to aid those skilled in the art. They are not intended to limit the scope of this invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, provided they do not affect the effectiveness or purpose of this invention, should still fall within the scope of the technical content disclosed in this invention. Furthermore, terms such as "upper," "lower," "front," "rear," and "middle" used in this specification are merely for clarity and not intended to limit the scope of this invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of this invention.
[0029] like Figure 1 As shown, the high-boiling material handling system in the production of high-crystalline silicon of this utility model mainly includes a concentration tower 4, a reaction vessel 12, a distillation tower 16, and a hydrogen chloride feeding unit.
[0030] The front end of the concentration tower 4 is connected to the high-boiling material outlet pipe 0 through the feed pipeline to receive the high-boiling material generated in the production of high-crystalline silicon; the bottom of the concentration tower 4 is connected to the reactor 12 through the pipeline to send the concentrated high-boiling material into the reactor 12 for further reaction; the top of the concentration tower 4 is connected to the top outlet pipe and sent to the STC main pipe 8.
[0031] The feed side of the reactor 12 is also connected to the reactor extractant injection pipeline 27 and the hydrogen chloride feeding unit. The bottom discharge is connected to the reactor external delivery pipeline 13, and the top is connected to the distillation column 16 through the collection pipeline.
[0032] The distillation column 16 is connected to the rear end of the reactor 12, with its bottom connected to the distillation column bottom feed line 15, and its top connected to the top feed line 19 and the hydrogen chloride feed unit via pipelines.
[0033] In this embodiment, a precision filter 1, a high-boiling feed buffer tank 2, and a concentration feed pump 3 are sequentially installed on the feed pipeline between the high-boiling material outlet pipe 0 and the concentration tower 4.
[0034] In this embodiment, a high-boiling reactor feed buffer tank 10 is also connected between the concentration tower 4 and the reactor 12.
[0035] In this embodiment, a reboiler pump 5 and a reboiler cooler 9 are sequentially installed on the pipeline between the concentration tower 4 and the feed buffer tank 10 of the high-boiling reactor.
[0036] In this embodiment, a reactor feed pump 11 is installed on the pipeline between the high-boiling reactor feed buffer tank 10 and the reactor 12.
[0037] In this embodiment, the top of the concentration tower 4 is sequentially equipped with a first top reflux tank 6, a top extraction pump 7, and a first activated carbon adsorption column 28.
[0038] In this embodiment, a distillation column bottom pump 14 is installed on the distillation column bottom feed line 15; a second top reflux tank 17 is installed on the top pipeline of the distillation column 16, and the second top reflux tank 17 is connected to the top feed line 19 of the coarse fractionation column and the hydrogen chloride feed unit through pipelines.
[0039] In this embodiment, a top reflux pump 18 and a second activated carbon adsorption column 29 are sequentially installed on the pipelines of the second top reflux tank 17 and the top extraction and external delivery coarse separation tower pipeline 19.
[0040] In this embodiment, a tower top cooler 20 and a vent VG1 main pipe 21 are installed on the pipeline between the second tower top reflux tank 17 and the hydrogen chloride feeding unit.
[0041] In this embodiment, the hydrogen chloride feeding unit includes a hydrogen chloride compressor pre-buffer tank 23, a hydrogen chloride compressor 24, and a hydrogen chloride compressor post-buffer tank 25 connected in sequence; the hydrogen chloride compressor post-buffer tank 25 is connected to the reactor 12 or the circulating hydrogen chloride external hydrogenation system pipeline 26 through pipelines; the hydrogen chloride compressor pre-buffer tank 23 is connected to the top outlet pipeline of the distillation column 16.
[0042] Combined with appendix Figure 1 The process flow of this system is as follows:
[0043] High-boiling-point (polysilane content approximately 5-10%) gas from the tail gas recovery unit in polysilicon production, high-boiling-point (polysilane content approximately 2-5%) gas from the hydrogenation coarse separation tower, and slurry clear liquid (containing high-boiling-point) are pumped to the front-end precision filter 1 for filtration to remove silicon powder.
[0044] The silica powder filtered by the filter is discharged to the slurry tank through the bottom discharge pipeline. The high-boiling clear liquid without silica powder after filtration enters the high-boiling feed buffer tank 2 and is transported to the concentration tower 4 for concentration and separation by the feed pump. The chlorosilanes collected from the top of the tower are mainly silicon tetrachloride. After impurity removal by the adsorption column, they are sent to the tetrachloride storage tank. The high-boiling liquid collected from the bottom of the tower (polysilane content of about 30-35%) is transported to the circulating water cooler by the bottom pump (including the filter), and after cooling, it is sent to the high-boiling reactor feed buffer tank 10.
[0045] The high-boiling point in the feed buffer tank 10 of the high-boiling reactor is pumped to the stirred reactor 12. HCl is sent to the stirred reactor through a compressor. Under the action of the catalyst (mixed with silicon tetrachloride and hydrogen chloride in a certain proportion), they react to produce trichlorosilane and silicon tetrachloride.
[0046] Steam is introduced into the jacket of the stirred tank reactor for heating. Gas-phase chlorosilanes and hydrogen chloride enter the high-boiling cracking distillation column 16 for separation. The chlorosilanes collected from the top of the column are sent to the hydrogenation synthesis unit after being purified by an adsorption column. The vent gas (HCl) from the distillation column is discharged to the compression unit of the hydrochloric acid desorption unit. It is mixed with fresh hydrogen chloride from the hydrochloric acid desorption and compressed by the low-pressure hydrogen chloride recovery compressor. Part of the mixture is recycled back into the stirred tank reactor, and the other part is sent to the hydrogenation system.
[0047] This utility model provides a concept and method for handling high-boiling-point materials in high-crystalline silicon production. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment of this utility model. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this utility model, and these improvements and modifications should also be considered within the scope of protection of this utility model. All components not explicitly stated in this embodiment can be implemented using existing technology.
Claims
1. A high-boiling-point material handling system for high-crystalline silicon production, characterized in that, It includes an enrichment tower (4), a reaction vessel (12), a distillation tower (16), and a hydrogen chloride feeding unit; The front end of the enrichment tower (4) is connected to the high-boiling material outlet pipe (0) through the feed pipeline to receive the high-boiling material generated in the production of high-crystalline silicon; the bottom of the enrichment tower (4) is connected to the reactor (12) through the pipeline to send the enriched high-boiling material into the reactor (12) for further reaction; the top of the enrichment tower (4) is connected to the top of the tower to be taken out and sent to the STC main pipe (8). The feed side of the reactor (12) is also connected to the reactor extractant injection pipeline (27) and the hydrogen chloride feeding unit. The bottom discharge is connected to the reactor external delivery pipeline (13), and the top is connected to the distillation column (16) through the collection pipeline. The distillation column (16) is connected to the rear end of the reactor (12), with its bottom connected to the distillation column bottom feed line (15) and its top connected to the top feed line (19) and the hydrogen chloride feed unit via pipelines.
2. The high-boiling-point material handling system in high-crystalline silicon production according to claim 1, characterized in that, A precision filter (1), a high-boiling feed buffer tank (2), and a concentration feed pump (3) are sequentially installed on the feed pipeline between the high-boiling material outlet pipe (0) and the concentration tower (4).
3. The high-boiling-point material handling system for high-crystalline silicon production according to claim 1, characterized in that, A high-boiling reactor feed buffer tank (10) is also connected between the concentration tower (4) and the reactor (12).
4. The high-boiling-point material handling system in high-crystalline silicon production according to claim 3, characterized in that, The pipeline between the concentration tower (4) and the feed buffer tank (10) of the high-boiling reactor is sequentially equipped with a concentration tower bottom pump (5) and a bottom cooler (9).
5. The high-boiling-point material handling system for high-crystalline silicon production according to claim 3, characterized in that, A reactor feed pump (11) is installed on the pipeline between the high-boiling reactor feed buffer tank (10) and the reactor (12).
6. The high-boiling-point material handling system for high-crystalline silicon production according to claim 1, characterized in that, The top of the concentration tower (4) is provided with a first top reflux tank (6), a top pump (7), and a first activated carbon adsorption column (28) in sequence on the top outflow pipeline.
7. The high-boiling-point material handling system for high-crystalline silicon production according to claim 1, characterized in that, The distillation column bottom feed line (15) is equipped with a distillation column bottom pump (14); the top pipeline of the distillation column (16) is equipped with a second top reflux tank (17), which is connected to the top feed line (19) of the coarse fractionation column and the hydrogen chloride feed unit through pipelines.
8. The high-boiling-point material handling system for high-crystalline silicon production according to claim 7, characterized in that, The second top reflux tank (17) and the pipeline of the top extraction and external delivery coarse separation tower (19) are respectively equipped with a top reflux pump (18) and a second activated carbon adsorption column (29).
9. The high-boiling-point material handling system for high-crystalline silicon production according to claim 7, characterized in that, The second top reflux tank (17) and the hydrogen chloride feeding unit are equipped with a top cooler (20) and a vent VG1 main pipe (21).
10. The high-boiling-point material handling system for high-crystalline silicon production according to claim 1, characterized in that, The hydrogen chloride feeding unit includes a hydrogen chloride compressor pre-buffer tank (23), a hydrogen chloride compressor (24), and a hydrogen chloride compressor post-buffer tank (25) connected in sequence; the hydrogen chloride compressor post-buffer tank (25) is connected to the reactor (12) or the circulating hydrogen chloride external hydrogenation system pipeline (26) through pipelines; the hydrogen chloride compressor pre-buffer tank (23) is connected to the top outlet pipeline of the distillation column (16).