CN1962434A - Technology of zinc reduction for producing polysilicon - Google Patents
Technology of zinc reduction for producing polysilicon Download PDFInfo
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- CN1962434A CN1962434A CN 200610134108 CN200610134108A CN1962434A CN 1962434 A CN1962434 A CN 1962434A CN 200610134108 CN200610134108 CN 200610134108 CN 200610134108 A CN200610134108 A CN 200610134108A CN 1962434 A CN1962434 A CN 1962434A
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Abstract
The invention discloses a polysilicon manufacturing technology through zinc reduced method, which comprises the following steps: aerating high-purity nitrogen or argon gas or composite gas into closed pipe quartz reactor to manufacture plasmid; reacting silicon chloride and zinc gas under plasmid gas according to reacting formula quantity; manufacturing silicon and zinc chloride; entering the composite gas into the first collector along pipe; controlling temperature between 1000 and 1500 Deg C; collecting particle-shaped high-purity silicon particle; fusing into block-shaped polysilicon; entering other composite gas into the second collector; controlling the temperature between 800 and 100 Deg C; sedimenting zinc chloride and non-reacted zinc; heating zinc chloride and zinc to fuse and separate; entering another composite gas into the third collector; cooling to 10-0 Deg C; collecting residual silicon chloride; sprinkling residual gas; discharging.
Description
Technical field
The present invention relates to a kind of technology of zinc reduction for producing polysilicon.
Background technology
Polycrystalline silicon material is very important intermediates in the silicon product industrial chain, is the main raw material of making silicon polished, solar cell and HIGH-PURITY SILICON goods, is information industry and the most basic starting material of new forms of energy industry.The autonomous supply of material of China's polysilicon exists serious breach, rely on import more than 95%, in recent years rising suddenly and sharply of polysilicon market price injures the normal operation of China's polysilicon downstream industry, and becomes the bottleneck of restriction China's information industry and photovoltaic industry development.
The method of producing polysilicon at present has: silicon tetrachloride method, trichlorosilane method and silane thermal decomposition process etc.The silicon tetrachloride method is with SiCl
4With metallurgical grade Si, H
2For raw material is produced high-purity Si H
4, SiH then
4Polysilicon is produced in thermolysis.The trichlorosilane method is to be that raw material is produced SiHCl with chlorine, hydrogen, metallurgical grade industrial silicon
3, again with SiHCl
3Hydrogen reduction generates polysilicon.Wherein, silicon tetrachloride method growth velocity is low, efficiency of conversion is low, yield poorly reduction temperature height, energy consumption height; And trichlorosilane method sedimentation velocity is slow, yield is low, consumed power is a lot, and the by-product silicon tetrachloride amount is big.These two kinds of methods all are unfavorable for preparing granular polycrystalline silicon, and byproduct is hydrochloric acid, and hydrochloric acid corrosion resistance is big, and recycling is difficulty all; Producing of hydrogen particularly, power consumption is also bigger, and purification techniques requires also high, brings certain degree of difficulty to technology.The silane thermal decomposition process silane thermal decomposition process is with H
2SiF
6, Na, Al, H
2For raw material is produced high-purity Si H
4, again with SiH
4Thermolysis, the preparation granular polycrystalline silicon, yield can arrive 〉=more than 98%.But the key of this technology is the preparation of high purity silane, the production technique of the high purity silane that present China does not also reach a standard; And silane is inflammable and explosive, oneself produce to drop into very greatly, and it is very expensive to buy raw material, and the transportation difficulty is brought certain difficulty to suitability for industrialized production.
Above method for preparing polysilicon all exists problems such as one-time investment is big, the construction period long, the input-output rate is low, production cost height.
China's polysilicon mainly shows 4 aspects with the gap of international most advanced level aspect industrial production: 1. processing unit falls behind, and causes material and power consumption excessive, and three wastes problem is many; 2. industrial scale is little, and present internationally recognized production of polysilicon critical economic scale is 1000t/a, and China only is 30～50t/a; 3. be difficult to obtain ultra-pure product (B＜0.03ppb); 4. cost does not have competitive power.Because raw and auxiliary material consumes height, industrial scale is little, so price is far above abroad.
Summary of the invention
The objective of the invention is to solve the problems referred to above that prior art exists, a kind of technology of zinc reduction for producing polysilicon is provided, this technology is raw material with high purity silicon tetrachloride and high purity zinc, under the rf induction plasma condition, one step obtained granular polycrystalline silicon, product is made the precursor that is fit to solar cell material or silicon single crystal by granulation, briquetting or fusion.This technology is plasma body gas-phase decomposition reduction reaction, be reflected in the airtight tubular reactor and finish, process is continuous, level of automation height, the continuous rewinding of continuous dosing, speed of response is fast, constant product quality, product purity height, three-waste free discharge, easy realization of industrialization, and the recyclable utilization of the by product that generates in the reaction process.
The present invention is achieved in that according to the mixed gas of reaction needed with high pure nitrogen or argon gas or high pure nitrogen and argon gas and feeds airtight tubular type quartz reactor and produce plasma body, silicon tetrachloride and zinc fume are reacted than in plasma atmosphere by the reaction formula weight, generate silicon and zinc chloride; Reaction mixture gas enters first collector along pipeline, between 1000 ℃-1500 ℃, collects silicon grain by the preservation and controlling temperature, makes polysilicon with granular HIGH-PURITY SILICON collection and through being melt into piece; Other mixed gas enters second collector, at 800～100 ℃, makes zinc chloride and unreacted zinc deposition by controlled temperature, and zinc chloride is separated by heat fused with zinc, and zinc recycles, and four zinc chloride are taken out as byproduct; Other gas mixtures enter the 3rd collector by cooling 10～0 ℃, collect remaining silicon tetrachloride, and it is recycled; Residual gas is sprayed the back discharging.
The technology of above-mentioned zinc reduction for producing polysilicon, the mixed gas flow of high pure nitrogen or argon gas or high pure nitrogen and argon gas are 5～10 meters
3/ hour.
The technology of above-mentioned zinc reduction for producing polysilicon, first collector adopts full quartz pipe, and duct length is 4～6 meters.
The technology of above-mentioned zinc reduction for producing polysilicon, second collector adopts white steel container, and volume is 1M
3～2M
3
The technology of above-mentioned zinc reduction for producing polysilicon, the 3rd collector adopts full quartz container, and volume is 0.5M
3～1M
3
The technology of above-mentioned zinc reduction for producing polysilicon, described high pure nitrogen or argon gas foreign matter content are less than 10ppm.
The technology of above-mentioned zinc reduction for producing polysilicon, described silicon tetrachloride purity is more than the 7N.
The technology of above-mentioned zinc reduction for producing polysilicon, described high purity zinc are electrolytic zinc, and purity 〉=99.999%.
The technology of this zinc reduction for producing polysilicon is raw material with high purity silicon tetrachloride and high purity zinc, and raw material cheaply is easy to get, and under the rf induction plasma condition, a step obtains granular polycrystalline silicon, and product is made impurity and is less than 1 * 10 by granulation, briquetting or fusion
-9Ultra-pure polysilicon, with precursor as solar cell material or silicon single crystal.This technology is plasma body gas-phase decomposition reduction reaction, is reflected in the airtight tubular reactor to finish, and process is continuous, and speed of response is fast, the level of automation height, the continuous rewinding of continuous dosing, constant product quality, the product purity height, manufacturing cost is low, easy realization of industrialization; Its by product is a zinc chloride, recyclable utilization, zinc chloride can be used as dewatering agent, condensing agent and the catalyzer of organic synthesis, the ionogen of the solvent that polypropylene is clear, fire foam, promoting agent, cationic dyestuff, mercerizing agent, sizing agent, weighting agent and drying battery, galvanized additive, rubber fluidizing promotor etc. are a kind of Industrial products of great use; The nitrogen that produces in the reaction process can directly discharge, so this technology three-waste free discharge.
Description of drawings
Fig. 1 is a process flow sheet of the present invention.
Embodiment
Embodiment 1:
As shown in the figure, at first silicon tetrachloride purity is reached more than the 7N by purification; According to reaction needed with the mixed gas of high pure nitrogen or argon gas or high pure nitrogen and argon gas with 5～10 meters
3/ hour feed airtight tubular type quartz reactor and produce plasma body (when adopting mixed gas, proportion relation between nitrogen and the argon gas is not limit), described high pure nitrogen or argon gas foreign matter content are less than 10ppm, make silicon tetrachloride and zinc fume by reaction formula weight ratio simultaneously, it reacts in plasma atmosphere, generates silicon and zinc chloride; Reaction mixture gas enters first collector along pipeline, between 1000 ℃-1500 ℃, collect silicon grain by the preservation and controlling temperature, make polysilicon with granular HIGH-PURITY SILICON collection and through being melt into piece, first collector adopts full quartz pipe, and duct length is 4～6 meters; Other mixed gas enters second collector, and second collector adopts white steel container, and volume is 1M
3～2M
3, at 800～100 ℃, make zinc chloride and unreacted zinc deposition by controlled temperature, zinc chloride is separated by heat fused with zinc, zinc recycles, and four zinc chloride are taken out as byproduct; Other gas mixtures enter the 3rd collector by cooling 10～0 ℃, collect remaining silicon tetrachloride, and it is recycled, and the 3rd collector adopts full quartz container, and volume is 0.5M
3～1M
3Residual gas (nitrogen) is sprayed the back discharging.
The environment protection aspect is handled:
(1) waste gas: the reduction operation is discharged the mixed gas that contains dust, and quantity is 20.5Nm per hour
3/ h wherein chloridely is about 1%, N
2: 99%.
Treatment measures: establish device for absorbing tail gas and dust collection, make that chlorinity reaches emission standard in the tail gas, simultaneously output zinc chloride product.
(2) waste water: the wastewater flow rate that the vent gas treatment absorption unit produces discharging in per 6 days is 50m once at every turn
3Its component is moisture 97%, HCl2.7%, ZnCl
20.3%, drain into water treatment system (neutralization tank) neutralization back up to standard discharging.
Embodiment 2:
As shown in the figure, at first silicon tetrachloride purity is reached more than the 7N by purification; According to reaction needed with the mixed gas of high pure nitrogen or argon gas or high pure nitrogen and argon gas with 5～6 meters
3/ hour feed airtight tubular type quartz reactor and produce plasma body (when adopting mixed gas, proportion relation between nitrogen and the argon gas is not limit), described high pure nitrogen or argon gas foreign matter content are less than 10ppm, make silicon tetrachloride and zinc fume by reaction formula weight ratio simultaneously, it reacts in plasma atmosphere, generates silicon and zinc chloride; Reaction mixture gas enters first collector along pipeline, between 1300 ℃-1500 ℃, collect silicon grain by the preservation and controlling temperature, make polysilicon with granular HIGH-PURITY SILICON collection and through being melt into piece, first collector adopts full quartz pipe, and duct length is 4～5 meters; Other mixed gas enters second collector, and second collector adopts white steel container, and volume is 1.5M
3～2M
3, at 400～100 ℃, make zinc chloride and unreacted zinc deposition by controlled temperature, zinc chloride is separated by heat fused with zinc, zinc recycles, and four zinc chloride are taken out as byproduct; Other gas mixtures enter the 3rd collector by cooling 10～0 ℃, collect remaining silicon tetrachloride, and it is recycled, and the 3rd collector adopts full quartz container, and volume is 0.5M
3～1M
3Residual gas (nitrogen) is sprayed the back discharging.
Embodiment 3:
As shown in the figure, at first silicon tetrachloride purity is reached more than the 7N by purification; According to reaction needed with the mixed gas of high pure nitrogen or argon gas or high pure nitrogen and argon gas with 9～10 meters
3/ hour feed airtight tubular type quartz reactor and produce plasma body (when adopting mixed gas, proportion relation between nitrogen and the argon gas is not limit), described high pure nitrogen or argon gas foreign matter content are less than 10ppm, make silicon tetrachloride and zinc fume by reaction formula weight ratio simultaneously, it reacts in plasma atmosphere, generates silicon and zinc chloride; Reaction mixture gas enters first collector along pipeline, between 1000 ℃-1200 ℃, collect silicon grain by the preservation and controlling temperature, make polysilicon with granular HIGH-PURITY SILICON collection and through being melt into piece, first collector adopts full quartz pipe, and duct length is 5～6 meters; Other mixed gas enters second collector, and second collector adopts white steel container, and volume is 1M
3～1.5M
3, at 800～600 ℃, make zinc chloride and unreacted zinc deposition by controlled temperature, zinc chloride is separated by heat fused with zinc, zinc recycles, and four zinc chloride are taken out as byproduct; Other gas mixtures enter the 3rd collector by cooling 10～0 ℃, collect remaining silicon tetrachloride, and it is recycled, and the 3rd collector adopts full quartz container, and volume is 0.5M
3～1M
3Residual gas (nitrogen) is sprayed the back discharging.
Embodiment 4:
As shown in the figure, at first silicon tetrachloride purity is reached more than the 7N by purification; According to reaction needed with the mixed gas of high pure nitrogen or argon gas or high pure nitrogen and argon gas with 7～8 meters
3/ hour feed airtight tubular type quartz reactor and produce plasma body (when adopting mixed gas, proportion relation between nitrogen and the argon gas is not limit), described high pure nitrogen or argon gas foreign matter content are less than 10ppm, make silicon tetrachloride and zinc fume by reaction formula weight ratio simultaneously, it reacts in plasma atmosphere, generates silicon and zinc chloride; Reaction mixture gas enters first collector along pipeline, between 1200 ℃-1300 ℃, collects silicon grain by the preservation and controlling temperature, makes polysilicon with granular HIGH-PURITY SILICON collection and through being melt into piece, and first collector adopts full quartz pipe, and duct length is 5 meters; Other mixed gas enters second collector, and second collector adopts white steel container, and volume is 1.5M
3, at 600～400 ℃, make zinc chloride and unreacted zinc deposition by controlled temperature, zinc chloride is separated by heat fused with zinc, zinc recycles, and four zinc chloride are taken out as byproduct; Other gas mixtures enter the 3rd collector by cooling 10～0 ℃, collect remaining silicon tetrachloride, and it is recycled, and the 3rd collector adopts full quartz container, and volume is 0.5M
3～1M
3Residual gas (nitrogen) is sprayed the back discharging.
Claims (8)
1, a kind of technology of zinc reduction for producing polysilicon, it is characterized in that: feed airtight tubular type quartz reactor and produce plasma body according to the mixed gas of reaction needed with high pure nitrogen or argon gas or high pure nitrogen and argon gas, silicon tetrachloride and zinc fume are reacted than in plasma atmosphere by the reaction formula weight, generate silicon and zinc chloride; Reaction mixture gas enters first collector along pipeline, between 1000 ℃-1500 ℃, collects silicon grain by the preservation and controlling temperature, makes polysilicon with granular HIGH-PURITY SILICON collection and through being melt into piece; Other mixed gas enters second collector, at 800～100 ℃, makes zinc chloride and unreacted zinc deposition by controlled temperature, and zinc chloride is separated by heat fused with zinc, and zinc recycles, and four zinc chloride are taken out as byproduct; Other gas mixtures enter the 3rd collector by cooling 10～0 ℃, collect remaining silicon tetrachloride, and it is recycled; Residual gas is sprayed the back discharging.
2, the technology of zinc reduction for producing polysilicon according to claim 1 is characterized in that: the mixed gas flow of high pure nitrogen or argon gas or high pure nitrogen and argon gas is 5～10 meters
3/ hour.
3, the technology of zinc reduction for producing polysilicon according to claim 1 is characterized in that: first collector adopts full quartz pipe, and duct length is 4～6 meters.
4, the technology of zinc reduction for producing polysilicon according to claim 1 is characterized in that: second collector adopts white steel container, and volume is 1M
3～2M
3
5, the technology of zinc reduction for producing polysilicon according to claim 1 is characterized in that: the 3rd collector adopts full quartz container, and volume is 0.5M
3～1M
3
6, the technology of zinc reduction for producing polysilicon according to claim 1 is characterized in that: described high pure nitrogen or argon gas foreign matter content are less than 10ppm.
7, the technology of zinc reduction for producing polysilicon according to claim 1 is characterized in that: described silicon tetrachloride purity is more than the 7N.
8, the technology of zinc reduction for producing polysilicon according to claim 1 is characterized in that: described high purity zinc is an electrolytic zinc, and purity 〉=99.999%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200610134108 CN1962434A (en) | 2006-10-31 | 2006-10-31 | Technology of zinc reduction for producing polysilicon |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200610134108 CN1962434A (en) | 2006-10-31 | 2006-10-31 | Technology of zinc reduction for producing polysilicon |
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| Publication Number | Publication Date |
|---|---|
| CN1962434A true CN1962434A (en) | 2007-05-16 |
Family
ID=38081690
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|---|---|---|---|
| CN 200610134108 Pending CN1962434A (en) | 2006-10-31 | 2006-10-31 | Technology of zinc reduction for producing polysilicon |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010022601A1 (en) * | 2008-08-31 | 2010-03-04 | 北京中晶华业科技有限公司 | Process for producing highly pure silicon |
| WO2010067842A1 (en) * | 2008-12-10 | 2010-06-17 | 住友化学株式会社 | Silicon manufacturing method |
| CN101934212A (en) * | 2009-06-30 | 2011-01-05 | 新疆天业（集团）有限公司 | Gas-solid/gas-gas phase plasma tubular reactor process and device |
| CN102089243A (en) * | 2008-02-20 | 2011-06-08 | Cbd能源有限公司 | Reduction of silica |
| CN101638232B (en) * | 2008-08-19 | 2012-04-18 | 储晞 | Method and device for producing high-purity silicon blank |
| CN102616784A (en) * | 2011-10-27 | 2012-08-01 | 内蒙古神舟硅业有限责任公司 | Method of reducing silicon tetrachloride with zinc powder in organic solvent to prepare solar grade polysilicon |
| CN102616785A (en) * | 2011-10-27 | 2012-08-01 | 内蒙古神舟硅业有限责任公司 | Method for preparing nano-silicon powder particles by reducing silicon tetrachloride with zinc |
| CN102686514A (en) * | 2009-12-22 | 2012-09-19 | Jnc株式会社 | Method for manufacturing polysilicon and method for manufacturing silicon tetrachloride |
| CN101875503B (en) * | 2009-04-30 | 2012-10-10 | 内蒙古神舟硅业有限责任公司 | Reaction device for preparing anhydrous zinc chloride |
| CN101723370B (en) * | 2008-10-13 | 2013-02-20 | 刘雅铭 | Polysilicon production method without silicon tetrachloride emission |
| CN103774216A (en) * | 2013-12-02 | 2014-05-07 | 内蒙古机电职业技术学院 | Method for producing solar grade polycrystalline silicon by molten salt electrolysis and directional solidification combination technique |
-
2006
- 2006-10-31 CN CN 200610134108 patent/CN1962434A/en active Pending
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102089243A (en) * | 2008-02-20 | 2011-06-08 | Cbd能源有限公司 | Reduction of silica |
| CN101638232B (en) * | 2008-08-19 | 2012-04-18 | 储晞 | Method and device for producing high-purity silicon blank |
| WO2010022601A1 (en) * | 2008-08-31 | 2010-03-04 | 北京中晶华业科技有限公司 | Process for producing highly pure silicon |
| CN101723370B (en) * | 2008-10-13 | 2013-02-20 | 刘雅铭 | Polysilicon production method without silicon tetrachloride emission |
| WO2010067842A1 (en) * | 2008-12-10 | 2010-06-17 | 住友化学株式会社 | Silicon manufacturing method |
| JP2010159204A (en) * | 2008-12-10 | 2010-07-22 | Sumitomo Chemical Co Ltd | Silicon manufacturing method |
| DE112009003720T5 (en) | 2008-12-10 | 2012-06-14 | National Institute For Materials Science | Process for the production of silicon |
| CN101875503B (en) * | 2009-04-30 | 2012-10-10 | 内蒙古神舟硅业有限责任公司 | Reaction device for preparing anhydrous zinc chloride |
| CN101934212A (en) * | 2009-06-30 | 2011-01-05 | 新疆天业（集团）有限公司 | Gas-solid/gas-gas phase plasma tubular reactor process and device |
| CN102686514A (en) * | 2009-12-22 | 2012-09-19 | Jnc株式会社 | Method for manufacturing polysilicon and method for manufacturing silicon tetrachloride |
| CN102616785A (en) * | 2011-10-27 | 2012-08-01 | 内蒙古神舟硅业有限责任公司 | Method for preparing nano-silicon powder particles by reducing silicon tetrachloride with zinc |
| CN102616784A (en) * | 2011-10-27 | 2012-08-01 | 内蒙古神舟硅业有限责任公司 | Method of reducing silicon tetrachloride with zinc powder in organic solvent to prepare solar grade polysilicon |
| CN102616784B (en) * | 2011-10-27 | 2016-05-04 | 内蒙古神舟硅业有限责任公司 | In organic solvent, zinc powder reduction silicon tetrachloride is prepared the method for solar-grade polysilicon |
| CN103774216A (en) * | 2013-12-02 | 2014-05-07 | 内蒙古机电职业技术学院 | Method for producing solar grade polycrystalline silicon by molten salt electrolysis and directional solidification combination technique |
| CN103774216B (en) * | 2013-12-02 | 2017-03-29 | 内蒙古机电职业技术学院 | The method that molten-salt electrolysis and directional solidification combination technique produce solar-grade polysilicon |
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