CN102442672B - Method for purifying and recycling impurity-containing chlorosilane and application of method in polysilicon production - Google Patents
Method for purifying and recycling impurity-containing chlorosilane and application of method in polysilicon production Download PDFInfo
- Publication number
- CN102442672B CN102442672B CN 201110297957 CN201110297957A CN102442672B CN 102442672 B CN102442672 B CN 102442672B CN 201110297957 CN201110297957 CN 201110297957 CN 201110297957 A CN201110297957 A CN 201110297957A CN 102442672 B CN102442672 B CN 102442672B
- Authority
- CN
- China
- Prior art keywords
- chlorosilane
- impure
- application according
- liquid
- chloride
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Silicon Compounds (AREA)
Abstract
The invention provides a method for purifying and recycling impurity-containing chlorosilane. The method comprises the steps of: (1) filtering an impurity-containing chlorosilane liquid to obtain a filtered chlorosilane liquid and solids; (2) evaporating the chlorosilane liquid filtered in the step (1) under a condition of enabling the chlorosilane to be in a gas state so as to obtain a chlorosilane gas and evaporation residues; and (3) condensing the gasified chlorosilane in the step (2) to obtain the chlorosilane liquid. The invention also provides an application of the method in a polysilicon production. Through the technical proposal, the chlorosilane and the impurities can be separated efficiently to realize recycling of the chlorosilane, improve production efficiency and reduce environmental pollution.
Description
Technical field
The present invention relates to a kind of with the method for impure chlorosilane purification recovery and the application in production of polysilicon thereof.
Background technology
Exhausted and the lasting soaring situation of oil price in the face of the our times traditional energy, the whole world just utilizes renewable energy source at active development.Sun power is as reproducible clear energy sources, because of its cleaning, safety, aboundresources have obtained fast development.Thereby, constantly increase as the demand of the high purity polycrystalline silicon of solar cell raw material, become the bright spot of investment.
At present, the improvement Siemens Method is the main flow technology of producing polysilicon both at home and abroad, and the raw material of this explained hereafter polysilicon is a trichlorosilane, and by product is a silicon tetrachloride.1 ton of polysilicon of every production consumes the trichlorosilane more than 20 tons, produces the silicon tetrachloride more than 15 tons.
Produce the method for trichlorosilane in the industry, all use " trichlorosilane synthesis method ", i.e. hydrogenchloride and silica flour reaction generates trichlorosilane; The method of processing silicon chloride in the industry adopts " silicon tetrachloride at low temperature hydride process " mostly, i.e. silicon tetrachloride and hydrogen and silica flour reaction generates trichlorosilane, and trichlorosilane returns the polysilicon system again.Because silica flour itself contains metallic impurity such as the iron, aluminium, calcium of 2%-3%, causes " trichlorosilane synthesis method " and " silicon tetrachloride at low temperature hydride process " to certainly lead to a certain amount of impure chlorosilane liquid.
Both at home and abroad the polysilicon factory and office method of managing impure chlorosilane mostly is " hydrolysis method " greatly, promptly impure chlorosilane and water reaction, and generation acid waste water is used alkali lye (for example NaOH or Ca (OH) again
2) the neutralizing acid wastewater, generate calcium chloride, to realize the harmless treatment of impure chlorosilane.Reaction formula is as follows:
SiHCl
3+(n+2)H
2O→SiO
2.nH
2O+3HCl+H
2↑
SiCl
4+(n+2)H
2O→SiO
2.nH
2O+4HCl
2HCl+Ca(OH)
2＝CaCl
2+2H
2O
The shortcoming that prior art exists is:
The first, an important link of production of polysilicon promptly is making full use of of silicon, two resources of chlorine.With the chlorosilane hydrolysis, can waste material, make " silicon " of production of polysilicon, " chlorine " magnitude of recruitment increase greatly;
The second, because the treatment capacity of impure chlorosilane is huge, the acid waste water amount that hydrolysis produces is huge equally, and acid waste water is dealt with improperly, still pollutes the environment;
The 3rd, neutralizing acid wastewater and the calcium chloride that produces are dealt with improperly, pollute the environment equally;
The 4th, silicon-dioxide that this process produces and calcium chloride are owing to poor quality, and purposes is limited, bulk deposition, land occupation.
Therefore, need improve, especially chlorosilane effectively be separated with impurity, make chlorosilane return the production of polysilicon system once more, thereby make its recycle improve the efficient of integrated artistic the recycling process of impure chlorosilane.
Summary of the invention
The objective of the invention is provides a kind of impure chlorosilane that effectively utilizes in order to solve chlorosilane waste, the problem of environmental pollution that prior art exists, and separating impurity reclaims the method for chlorosilane.
To achieve these goals, the invention provides a kind of method that impure chlorosilane purification is reclaimed, it is characterized in that this method may further comprise the steps:
(1) with impure chlorosilane liquid filtering, chlorosilane liquid and solids after obtaining filtering;
(2) be to evaporate under the gasiform condition the chlorosilane liquid after filtering in the step (1) making chlorosilane, obtain chlorosilane gas and evaporation residue;
(3) with the chlorosilane condensation after the gasification in the step (2), obtain chlorosilane liquid.
The present invention also provides the application of aforesaid method in production of polysilicon.
Pass through technique scheme, impure chlorosilane is separated, can obtain the higher chlorosilane liquid of purity, the higher chlorosilane liquid of this purity can return the step that " silicon tetrachloride at low temperature hydrogenation system " produces trichlorosilane in the polysilicon system again, thereby forms polysilicon " closed loop " production.Solve the environmental problem that impure chlorosilane hydrolysis brings on the one hand, also effectively saved resource on the other hand, reduced production cost.
Other features and advantages of the present invention will partly be described in detail in embodiment subsequently.
Description of drawings
Accompanying drawing is to be used to provide further understanding of the present invention, and constitutes the part of specification sheets, is used from explanation the present invention with following embodiment one, but is not construed as limiting the invention.In the accompanying drawings:
Fig. 1 is the process flow diagram that impure chlorosilane is purified a kind of embodiment of the method that reclaims provided by the invention.
Description of reference numerals
1 transferpump, 2 strainers
3 flash distillation stills, 4 condensers
5 storage tanks
Embodiment
Below in conjunction with accompanying drawing the specific embodiment of the present invention is elaborated.Should be understood that embodiment described herein only is used for description and interpretation the present invention, is not limited to the present invention.
The invention provides a kind of method that impure chlorosilane purification is reclaimed, it is characterized in that this method may further comprise the steps:
(1) with impure chlorosilane liquid filtering, chlorosilane liquid and solids after obtaining filtering;
(2) be to evaporate under the gasiform condition the chlorosilane liquid after filtering in the step (1) making chlorosilane, obtain chlorosilane gas and evaporation residue;
(3) with the chlorosilane condensation after the gasification in the step (2), obtain chlorosilane liquid.
A kind of optimal way according to the present invention, described chlorosilane are trichlorosilane and/or silicon tetrachloride.
Among the present invention, the impurity in the described impure chlorosilane liquid is meant the material except that above-mentioned chlorosilane.
A kind of optimal way according to the present invention, described impurity comprise one or more in one or more and iron(ic) chloride in iron, aluminium, calcium, boron, phosphorus, the titanium, aluminum chloride, calcium chloride, boron chloride, phosphorus chloride, the titanium chloride.
A kind of optimal way according to the present invention, described impure chlorosilane derive from the trichlorosilane synthesis method and produce trichlorosilane technology and/or silicon tetrachloride at low temperature hydride process production trichlorosilane technology.The trichlorosilane synthesis method produces trichlorosilane technology and/or silicon tetrachloride at low temperature hydride process production trichlorosilane technology is well known to those skilled in the art, and the present invention does not repeat them here.
It can be the various filtration unit that can realize solid-liquid separation of the present invention well known in the art that the present invention filters with device.Consider from the angle of production efficiency, be preferably high efficiency filter.More preferably adopt porcelain filter to carry out.Porcelain filter has good slag dumping ability and cleaning regenerability.The aperture of porcelain filter of the present invention is preferably 1-50 μ m.20-30 μ m more preferably.
It is to make the chlorosilane gasification that purpose is evaporated in the present invention, can realize with known various evaporation equipments, for example vaporizer, flash distillation still etc.Vaporization temperature can be selected in relative broad range, boiling point is higher than the impurity of chlorosilane as long as can make the chlorosilane evaporation become gas does not become gas, the temperature of preferred evaporation is than the high 0-20 of chlorosilane boiling point ℃, as is preferably 60-150 ℃, more preferably 80-100 ℃.Evaporating pressure is preferably 0.05-0.5MPa.0.08-0.09MPa more preferably.Above-mentioned pressure all refers to gauge pressure.Evaporating pressure maintains in this gauge pressure scope, and it is smooth and easy to guarantee to evaporate back air-flow height, helps the collection and the utilization of follow-up chlorosilane.
The condensation of chlorosilane gas of the present invention can such as recirculated water condensation method, and be passed through multiple condensing equipment well known in the art and realize with multiple condensation method well known in the art.The temperature of described condensation can be selected in the scope of broad, as long as can make chlorosilane liquefaction be liquid, the low boiling component that other boiling points are low than chlorosilane still gets final product for gas.The temperature of preferred condensation be that the boiling point than chlorosilane hangs down 1-20 ℃.Make that the temperature of chlorosilane is 25-35 ℃ after the described condensation.Make that more preferably the temperature of chlorosilane is 25-30 ℃ after the described condensation.
The preferred process of the present invention comprises that also the evaporation residue that step (2) is obtained carries out drying, obtains solid waste and waste gas.The exsiccant temperature is preferably 60-200 ℃.More preferably 100-150 ℃.Can be through primary drying or repeatedly dry.Preferably guarantee the thorough drying of solid waste and discharging smoothly by stirring the exsiccant mode.
The inventive method is preferably carried out in sealed environment.Sealing means can be various sealing means well known in the art, for example mechanical seal, magnetic seal etc.For chlorosilane in the realization response " zero leakage ", more preferably under the magnetic seal environment, carry out.
Method provided by the invention can be used for chlorosilane with various impure chlorosilanes and purify and reclaim, the content of chlorosilane wherein is not particularly limited, but consider that from the angle of economy the chlorosilane content in the preferred impure chlorosilane is 90-99 weight %.When described chlorosilane was the mixture of multiple chlorosilane, the mixture that can adopt aforesaid method to obtain chlorosilane adopted method well known in the art further that multiple chlorosilane is separated from each other afterwards, perhaps is used for subsequent technique without separation.
The present invention also provides the application of aforesaid method in production of polysilicon.Because method of the present invention can obtain the higher chlorosilane liquid of purity, the higher chlorosilane liquid of this purity can return the step that " silicon tetrachloride at low temperature hydrogenation system " produces trichlorosilane in the polysilicon system again, thereby forms polysilicon " closed loop " production.Therefore, a preferred embodiment of the invention, method of the present invention comprise that also gained liquid chlorosilane is returned " silicon tetrachloride at low temperature hydrogenation system " in the polysilicon system to be produced in the step of trichlorosilane.
Below in conjunction with Fig. 1 the method that impure chlorosilane purification is reclaimed provided by the invention is elaborated.As shown in Figure 1, with impure chlorosilane liquid by transferpump 1 carry filter out solid impurity through strainer 2 after, enter flash distillation still 3, the silicon tetrachloride after the gasification enters condenser 4, condensed silicon tetrachloride is temporary in storage tank 5.
Purify in the recovery system at this chlorosilane, the steam/heat Oil Guide is used for providing energy to flash distillation still 3.Recirculated water cooling condenser 4 adopts the mode of operation of recirculated water cooling, conserve water resource.Tail gas can produce collection in each step, and enters three wastes treatment station and handle.Nitrogen is to provide the gas of inertia protection for system's open, stop displacement and safe operation.Pressurized air is used to the variable valve action of each device that source of the gas is provided.
Embodiment 1
This embodiment is used to illustrate the method that reclaims that impure chlorosilane is purified provided by the invention.
Adopt flow process shown in Figure 1.Get the impure chlorosilane liquid 1000L that the trichlorosilane synthesis technique obtains, record with mass spectrograph, in this impure silicon tetrachloride liquid, the content 97wt% of silicon tetrachloride, the Fe foreign matter content is 1wt%, the Al foreign matter content is 1wt%, and the Ca foreign matter content is 0.5wt%, and other impurity (B, P, Ti) content is 0.5wt%.
The silicon tetrachloride liquid that this is impure is carried through strainer 2 by transferpump 1 and (is selected Stainless Steel Filter for use, the aperture is 20 μ m) filter out solid impurity after, enter flash distillation still 3, control still internal pressure 0.08MPa, 80 ℃ of temperature, silicon tetrachloride after the gasification enters condenser 4, and condensed silicon tetrachloride (temperature is 30 ℃) is temporary in storage tank 5.Record with gas chromatograph, silicon tetrachloride purity is 99.99% in the storage tank 5.
Embodiment 2
This embodiment is used to illustrate the method that reclaims that impure chlorosilane is purified provided by the invention.
Adopt flow process shown in Figure 1.Produce the impure chlorosilane liquid that polysilicon process obtains through the silicon tetrachloride at low temperature hydride process.Record with mass spectrograph, in this impure chlorosilane liquid, the content 90wt% of silicon tetrachloride, the content 7wt% of trichlorosilicane, Fe foreign matter content are 1wt%, and the Al foreign matter content is 1wt%, the Ca foreign matter content is 0.5wt%, and other impurity (B, P, Ti) content is 0.5wt%.
The chlorosilane liquid that this is impure is carried through strainer 2 by transferpump 1 continuously and (is selected strainer for use, the aperture is 30 μ m) filter out solid impurity after, enter flash distillation still 3, control still internal pressure 0.09MPa, 100 ℃ of temperature, chlorosilane after the gasification enters condenser 4, and condensed chlorosilane (temperature is 26 ℃) is temporary in storage tank 5.Record with gas chromatograph, silicon tetrachloride purity is 92.79% in the storage tank 5,, the purity of trichlorosilicane is 7.31%.Liquid in the storage tank 5 is returned production of polysilicon technology.
The impurity of flash distillation still 3 bottoms is carried out drying under 150 ℃, carry out under 100 ℃ repeatedly dryly again, discharge solid impurity and tail gas at last.
Embodiment 3
This embodiment is used to illustrate the method that reclaims that impure chlorosilane is purified provided by the invention.
Adopt flow process shown in Figure 1.Get the impure chlorosilane liquid of 1000L.Record with mass spectrograph, in this impure chlorosilane liquid, the content 90wt% of silicon tetrachloride, the content 7wt% of trichlorosilicane, Fe foreign matter content are 1wt%, and the Al foreign matter content is 1wt%, the Ca foreign matter content is 0.5wt%, and other impurity (B, P, Ti) content is 0.5wt%.
The chlorosilane liquid that this is impure is carried through strainer 2 by transferpump 1 continuously and (is selected porcelain filter for use, the aperture is 25 μ m) filter out solid impurity after, enter flash distillation still 3, control still internal pressure 0.07MPa, 85 ℃ of temperature, chlorosilane after the gasification enters condenser 4, and condensed chlorosilane (temperature is 25 ℃) is temporary in storage tank 5.Record with gas chromatograph, silicon tetrachloride purity is 92.79% in the storage tank 5, and the purity of trichlorosilicane is 7.31%.
The impurity of flash distillation still 3 bottoms is carried out drying under 125 ℃, the discharging solid impurity.
Claims (10)
1. the application of method in production of polysilicon that impure chlorosilane purification is reclaimed is characterized in that this method may further comprise the steps:
(1) with impure chlorosilane liquid filtering, chlorosilane liquid and solids after obtaining filtering;
(2) be to evaporate under the gasiform condition the chlorosilane liquid after filtering in the step (1) making chlorosilane, obtain chlorosilane gas and evaporation residue;
(3) with the chlorosilane condensation after the gasification in the step (2), obtain chlorosilane liquid.
2. application according to claim 1, wherein, described chlorosilane is trichlorosilane and/or silicon tetrachloride.
3. application according to claim 1, wherein, described impurity comprises one or more in one or more and iron(ic) chloride in iron, aluminium, calcium, boron, phosphorus, the titanium, aluminum chloride, calcium chloride, boron chloride, phosphorus chloride, the titanium chloride.
4. application according to claim 1, wherein, described impure chlorosilane derives from the trichlorosilane synthesis method and produces trichlorosilane technology and/or silicon tetrachloride at low temperature hydride process production trichlorosilane technology.
5. application according to claim 1, wherein, described filtration adopts porcelain filter to carry out.
6. application according to claim 5, wherein, the aperture of described porcelain filter is 1-50 μ m.
7. application according to claim 1, wherein, described vaporization temperature is 60-150 ℃, evaporating pressure is 0.05-0.5MPa.
8. application according to claim 1, wherein, this method comprises that also the evaporation residue that step (2) is obtained carries out drying, obtains solid waste and waste gas.
9. application according to claim 1, wherein, the temperature of chlorosilane is 25-35 ℃ after the described condensation.
10. according to any described application among the claim 1-9, wherein, this method is carried out under magnetic seal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110297957 CN102442672B (en) | 2011-09-28 | 2011-09-28 | Method for purifying and recycling impurity-containing chlorosilane and application of method in polysilicon production |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110297957 CN102442672B (en) | 2011-09-28 | 2011-09-28 | Method for purifying and recycling impurity-containing chlorosilane and application of method in polysilicon production |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102442672A CN102442672A (en) | 2012-05-09 |
| CN102442672B true CN102442672B (en) | 2013-07-24 |
Family
ID=46005671
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201110297957 Expired - Fee Related CN102442672B (en) | 2011-09-28 | 2011-09-28 | Method for purifying and recycling impurity-containing chlorosilane and application of method in polysilicon production |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102442672B (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103331057B (en) * | 2013-07-19 | 2015-07-15 | 新特能源股份有限公司 | Filtering device for silica powder in liquid chlorosilane |
| CN104415560A (en) * | 2013-08-24 | 2015-03-18 | 内蒙古盾安光伏科技有限公司 | Polysilicon cold hydrogenation raffinate recovery system |
| CN105480980B (en) * | 2014-09-17 | 2018-06-08 | 新特能源股份有限公司 | The slurry treating method and apparatus that a kind of trichlorosilane produces |
| CN104841195A (en) * | 2015-06-02 | 2015-08-19 | 中国恩菲工程技术有限公司 | Purification and recovery device for chlorosilane waste liquid and purification and recovery method for chlorosilane waste liquid |
| KR102292341B1 (en) * | 2017-01-16 | 2021-08-24 | 가부시끼가이샤 도꾸야마 | Method for manufacturing polycrystalline silicon |
| CN108383125B (en) * | 2018-05-14 | 2020-02-28 | 亚洲硅业(青海)股份有限公司 | Device and method for preparing high-purity trichlorosilane |
| CN110542725A (en) * | 2018-05-29 | 2019-12-06 | 新疆新特新能材料检测中心有限公司 | Process for detecting nitrogen in hydrogen |
| CN110624268A (en) * | 2019-09-16 | 2019-12-31 | 广州汇富研究院有限公司 | Chlorosilane purifying device and purifying method thereof |
| CN115106045B (en) * | 2022-07-26 | 2024-03-29 | 乐山协鑫新能源科技有限公司 | High-boiling treatment system for slurry |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1517352A (en) * | 2003-01-15 | 2004-08-04 | �����Ʒ�뻯ѧ��˾ | Producing and purifying method of bi (Tert-butyl amino) silane |
| CN101148453A (en) * | 2006-09-21 | 2008-03-26 | 蓝星化工新材料股份有限公司 | Dry dust removing method by using inorganic chlorosilane gas and device thereof |
-
2011
- 2011-09-28 CN CN 201110297957 patent/CN102442672B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1517352A (en) * | 2003-01-15 | 2004-08-04 | �����Ʒ�뻯ѧ��˾ | Producing and purifying method of bi (Tert-butyl amino) silane |
| CN101148453A (en) * | 2006-09-21 | 2008-03-26 | 蓝星化工新材料股份有限公司 | Dry dust removing method by using inorganic chlorosilane gas and device thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102442672A (en) | 2012-05-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102442672B (en) | Method for purifying and recycling impurity-containing chlorosilane and application of method in polysilicon production | |
| CN101327912B (en) | Method for reclaiming hydrogen from tail gas from polysilicon production | |
| CN101357764B (en) | Polysilicon preparation method of recovering hydrogen chloride in circulating exhaust | |
| CN101569817B (en) | Tail gas recycling method in trichlorosilane production | |
| CN101125276A (en) | Method for recovering tail gas of trichlorosilane production | |
| CN101377376A (en) | Method for recovering tail gas generated by polycrystalline silicon production | |
| CN103435044A (en) | Method for purifying and separating chlorosilane from polysilicon tail gas | |
| CN105036081A (en) | Method for producing HCl gas through chlorosilane residual liquor | |
| CN204058313U (en) | A kind of apparatus system recycling chlorosilane slag slurry raffinate | |
| CN103382032A (en) | Preparation method for trichlorosilane from silicon tetrachloride | |
| CN103449446B (en) | Method for preparing trichlorosilane | |
| CN101538043B (en) | Method for recovering trichlorosilane synthesis tail gas | |
| CN101376499A (en) | Method for preparing polysilicon | |
| CN103449440B (en) | Equipment for preparing polycrystalline silicon | |
| CN103449448A (en) | Equipment for purifying trichlorosilane | |
| CN202766304U (en) | Polysilicon production tail gas recycling device | |
| CN101372336A (en) | Method for preparing polysilicon | |
| CN104072530A (en) | Device system and method for recycling chlorosilane residual slurry liquid | |
| CN101830495B (en) | Comprehensive utilization method of chlorosilane | |
| CN102897770A (en) | Method and device for improving hydrogenation of silicon tetrachloride | |
| CN116143078A (en) | System and method for recycling hydrogen chloride in polycrystalline silicon tail gas | |
| CN214327178U (en) | Processing system of fluorine-containing nitric acid waste liquid | |
| CN101372335B (en) | Method for preparing polysilicon | |
| CN209411790U (en) | A kind of Finestill energy-saving apparatus purified for restoring chlorosilane | |
| CN103482630A (en) | Method for preparing polycrystalline silicon |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130724 Termination date: 20140928 |
|
| EXPY | Termination of patent right or utility model |