CN1693192A - Process for pressure purification of silicon trichlorohydrgen and apparatus thereof - Google Patents
Process for pressure purification of silicon trichlorohydrgen and apparatus thereof Download PDFInfo
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- CN1693192A CN1693192A CN 200510200334 CN200510200334A CN1693192A CN 1693192 A CN1693192 A CN 1693192A CN 200510200334 CN200510200334 CN 200510200334 CN 200510200334 A CN200510200334 A CN 200510200334A CN 1693192 A CN1693192 A CN 1693192A
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- trichlorosilane
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Abstract
A process and apparatus for pressure purifying of trichlorosilane is disclosed. Said process includes such steps as distilling the mixed liquid of trichlorosilane, SiCl4 and chlorosilane at 70-200 deg.C under 0.15-1.5 MPa, sending the vapor derived from distilled into purifying tower for the exchange and separation of heat and components at 40-150 deg.C, enriching the low-boiling-point trichlorosilane in vapor phase and the high-boiling-point SiCl4 in liquid phase, evaporating and condensaing several times to obtain trichlorosilane vapor, and condensing to obtain liquid-phase trichlorosilane.
Description
(1), technical field
The present invention relates to a kind of method of purification and device thereof of method of purification and equipment thereof, particularly a kind of trichlorosilane of chemical materials.
(2), background technology
Polysilicon is a raw material of producing computer chip and semiconducter device, is called as " foundation stone of Microelectronics Building ", and trichlorosilane (SiHcl
3) purification techniques is one of gordian technique of producing polysilicon.Existing trichlorosilane purifying technique is linked in sequence by still kettle, purification tower and overhead condenser and forms, and belongs to highly energy-consuming technology, and the proportion that energy charge accounts for total cost is very big.Along with the exhaustion day by day of worldwide petroleum resources, energy prices go up significantly, and the production cost of this technology is also corresponding to be increased greatly, and some developed countries have been unwilling to continue to increase input on this high energy-consuming industry, shift to developing country gradually.Siemens adopts the normal pressure process for separating and purifying in the purification of trichlorosilane, when adopting this explained hereafter, overhead condensation needs to freeze system with 7 ℃ of water-cooleds, therefore, need 7 ℃ of water-cooleds of investment construction to freeze system, make this method working cost and maintenance cost height, investment is high, energy consumption is high, causes the trichlorosilane production cost high.
(3), summary of the invention
The purpose of this invention is to provide a kind of Trichlorosilane Pressurizing Purifying Method And Device, solve that existing trichlorosilane purifying technology parameter is unreasonable, energy consumption is high, working cost and maintenance cost height, the high problem of investment.
Technical scheme of the present invention: this process for pressure purification of silicon trichlorohydrgen is characterized in that its method and technical parameter are as follows:
(1), trichlorosilane (SiHCl that will be to be purified
3), silicon tetrachloride (SiCl
4) charging opening of chlorosilane mixed solution input purification tower, mixed solution flow to still kettle under purification tower;
(2), add thermal still to 70 ℃～200 ℃, make the mixing liquid of trichlorosilane and silicon tetrachloride be distilled and produce vaporization, the still kettle control pressure is 0.15MPa～1.5MPa with heating agent;
(3), the boil-off of coming out from the still kettle steam discharge pipe enters the purification tower by pipe connecting, the service temperature in the purification tower is 40～150 ℃, from the SiHCl of still kettle
3, SiCl
4The mixing steam exchange of on the sieve plates at different levels of purification tower, carrying out heat and composition with separate, the enrichment in vapour phase of low-boiling trichlorosilane component, silicon tetrachloride component enrichment in liquid phase that boiling point is high, through repeatedly partly vaporizing or partial condensation, finally in vapour phase, obtain volatile, purer trichlorosilane vaporized component, in purification tower, obtain the high silicon tetrachloride component of boiling point;
(4), the trichlorosilane vaporized component of coming out from purification tower enters the overhead water condenser by conduit, the overhead water condenser adopts the ordinary cycle water cooling, the trichlorosilane vaporized component is condensed into liquid, promptly low-boiling trichlorosilane liquid through cooling;
(5), discharge more difficult evaporable silicon tetrachloride liquid from the liquid discharge pipe of still kettle.
Heating agent described in above-mentioned (1) is steam, hot water or thermal oil.
SiHCl to be purified described in above-mentioned (1)
3, SiCl
4The chlorosilane mixed solution adds between the 8th to the 35th block of column plate of purification tower by the charging opening of purification tower.
Still kettle, purification tower and overhead water condenser polyphone that above-mentioned two covers or two covers are above form slightly the heating up in a steamer of pressurization continuously, rectifying and purifying system.
This trichlorosilane pressurization purifying plant, purification tower is a sieve-plate structure, have charging opening on the tower side wall, it is characterized in that: be connected in series in proper order by still kettle, purification tower and overhead water condenser, the steam discharge pipe of still kettle is communicated with purification tower through pipe connecting, the purification tower top is communicated with the overhead water condenser through conduit, and the bottom vent pipe of above-mentioned still kettle and purification tower is communicated with the silicon tetrachloride liquid storage tank, and the liquid discharge pipe of overhead water condenser bottom is communicated with the trichlorosilane storage tank.
The position of charging opening is between the 8th to the 35th block of column plate of purification tower on the above-mentioned purification tower.
The present invention has utilized SiHCl
3, SiCl
4Boiling point with working pressure raise increase, ultimate principle that the relative volatility of the two is directly proportional with boiling-point difference.SiHCl
3, SiCl
4Mixture under the pressurized operation condition of still kettle, gas phase raises with pressure, density increases, viscosity increases; Liquid phase raises with pressure, and service temperature improves, and density of liquid phase reduces, and viscosity reduces.The plate efficiency liquid body viscosity influence of rectification and purification tower is big, and viscosity reduces, and total tray efficiency rises, and helps SiHCl
3And SiCl
4Separation.The present invention is increased to 0.15Mpa～1.5Mpa with the pressure range of still kettle; The operating temperature range of purification still kettle is increased to 70～200 ℃; Operating temperature range in the purification tower is increased to 40～150 ℃; Change 7 ℃ of refrigerated waters of overhead water condenser the water cooling of into employing ordinary cycle.And designed the equipment that is fit to upward pressure, temperature condition.
After the present invention has strengthened the pressure of purification tower,, help SiCl owing to rectification and purification pressure height, temperature height
4And SiHCl
3Separation, through impurity separating effects such as B, P relatively, separate BCl
3Than normal pressure purification tower remarkable advantages is arranged with the pressurization purification tower.Under the condition of pressurization, BCl
3Deng lower-boiling impurity muriate every plate enrichment multiple and accumulation rate than condition of normal pressure height, BCl
3Almost eliminate at cat head.After adopting technology of the present invention, can strengthen production system and equipment, the rectifying tower output of same tower diameter improves 50%; Changing 7 ℃ of water coolants is normal temperature ordinary cycle cooling process, has reduced freezing required facility investment and equipment working cost, and under the pressurized conditions, it is about 15% that the heat exchange efficiency of interchanger improves, and helps saving cold consumption.
The present invention uses in the embodiment that produces 2000 tons of trichlorosilanes per year, saves refrigeration system and invests 1,200,000 yuan.Save working cost: product per ton can be saved cold 107 * 10
4Kcal saves power consumption of refrigerating 300kWh/t.Under the pressurized conditions, it is about 15% that the heat exchange efficiency of interchanger improves, and under the condition of equal production capacity, equipment can reduce 15%, reduces facility investment and occupation area of equipment thus.
The present invention removes some electrically active impurities through purifying technique, carbon and transition element impurity, make the purity of SiHCl3 reach semiconductor grade standard-required, the separation that is applicable to all trichlorosilanes is purified, and is applicable to that the trichlorosilane in the production of polysilicon of solar battery grade polysilicon production and unicircuit level slightly heats up in a steamer and rectification and purification.
(4), description of drawings
Fig. 1 is the structural representation of trichlorosilane pressurization purifying plant of the present invention.
Among the figure: 1-still kettle, 2-purification tower, 3-overhead water condenser, 4-pipe connecting, 5-conduit, 6-silicon tetrachloride liquid storage tank, 7-trichlorosilane storage tank, 8-charging opening.
(5), embodiment
Embodiment is referring to Fig. 1, and still kettle 1 adopts the shell and tube heat exchanger that is suitable for the distillation procedure condition, operation of equipment pressure range: 0.15Mpa～1.5Mpa, operating temperature range: 70～200 ℃.Add thermal still 1 with steam, hot water or heat conduction wet goods heating agent, make the trichlorosilane and the silicon tetrachloride liquid vaporization that are distilled, the steam that is vaporized enters in the purification 2 by pipe connecting 4.
In the tower of purification tower 2 is the sieve-board type structure, operation of equipment pressure range: 0.15Mpa～1.5Mpa; Operating temperature range: 40～150 ℃.SiHCl from still kettle 1
3, SiCl
4The mixing steam exchange of on the sieve plates at different levels of purification tower, carrying out heat and composition with separate low-boiling component (SiHCl
3) enrichment in vapour phase, the component (SiCl that boiling point is high
4) enrichment in liquid phase, through repeatedly partly vaporizing or partial condensation, finally in vapour phase, obtain purer volatile components (SiHCl
3), in still kettle, obtain the high component (SiCl of boiling point
4), SiHCl to be purified
3, SiCl
4The charging opening 8 of mixed solution between the 8th to the 33rd block of column plate of purification tower 2 adds.
Overhead water condenser 3 adopts the shell and tube heat exchanger that is suitable for the condensation operation condition, and refrigerant adopts ordinary cycle water.Operation of equipment pressure range: 0.15Mpa-1.5Mpa, operating temperature range: 20～120 ℃.Enter overhead water condenser 3 from the component of purification tower 2 vaporizations by conduit 5, become liquid through cooling condensation, promptly low-boiling component (trichlorosilane).Regularly discharge more difficult volatiles from the liquid discharge pipe of still kettle 1, promptly obtain the high component of boiling point (silicon tetrachloride) and be stored in silicon tetrachloride liquid storage tank 6.
This trichlorosilane pressurization purifying plant, be connected in series by still kettle 1, purification tower 2 and overhead water condenser 3 orders, the steam discharge pipe of still kettle 1 is communicated with purification tower 2 through pipe connecting 4, the purification tower top is communicated with overhead water condenser 3 through conduit 5, the bottom vent pipe of above-mentioned still kettle 1 and purification tower 2 is communicated with silicon tetrachloride liquid storage tank 6, the liquid discharge pipe of overhead water condenser 3 bottoms is communicated with trichlorosilane storage tank 7, and above-mentioned overhead water condenser is the ortho-water condenser.
The position of charging opening 8 is between the 8th to the 35th block of column plate of purification tower on the purification tower.SiHCl
3, SiCl
4Chlorosilane mixed solution charging opening between the 8th to the 33rd block of column plate of purification tower adds, and filling tube is communicated with chlorosilane mixed solution storage tank.
Two covers or above still kettle, purification tower and the overhead water condenser of two covers are made up, can form slightly the heating up in a steamer of continuous pressurization, rectifying and purifying system, can satisfy trichlorosilane and silicon tetrachloride purifying technique that different purity requires.
Claims (6)
1. process for pressure purification of silicon trichlorohydrgen is characterized in that its method and technical parameter are as follows:
(1), the charging opening of trichlorosilane (SiHCl3) that will be to be purified, silicon tetrachloride (SiCl4) chlorosilane mixed solution input purification tower, mixed solution flow to still kettle under purification tower;
(2), add thermal still to 70 ℃～200 ℃, make the mixing liquid of trichlorosilane and silicon tetrachloride be distilled and produce vaporization, the still kettle control pressure is 0.15MPa～1.5MPa with heating agent;
(3), the boil-off of coming out from the still kettle steam discharge pipe enters the purification tower by pipe connecting, service temperature in the purification tower is 40～150 ℃, SiHCl3 from still kettle, the mixing steam of SiCl4 carries out heat and composition on the sieve plates at different levels of purification tower exchange with separate, the enrichment in vapour phase of low-boiling trichlorosilane component, silicon tetrachloride component enrichment in liquid phase that boiling point is high, through repeatedly partly vaporizing or partial condensation, finally in vapour phase, obtain volatile, purer trichlorosilane vaporized component obtains the high silicon tetrachloride component of boiling point in purification tower;
(4), the trichlorosilane vaporized component of coming out from purification tower enters the overhead water condenser by conduit, the overhead water condenser adopts the ordinary cycle water cooling, the trichlorosilane vaporized component is condensed into liquid, promptly low-boiling trichlorosilane liquid through cooling;
(5), discharge more difficult evaporable silicon tetrachloride liquid from the liquid discharge pipe of still kettle.
2. process for pressure purification of silicon trichlorohydrgen according to claim 1 is characterized in that: the heating agent described in above-mentioned (1) is steam, hot water or thermal oil.
3. process for pressure purification of silicon trichlorohydrgen according to claim 1 is characterized in that: the SiHCl3 to be purified described in above-mentioned (1), SiCl4 chlorosilane mixed solution add between the 8th to the 35th block of column plate of purification tower by the charging opening of purification tower.
4. according to claim 1 or 2 or 3 described process for pressure purification of silicon trichlorohydrgen, it is characterized in that: still kettle, purification tower and overhead water condenser polyphone that above-mentioned two covers or two covers are above form slightly the heating up in a steamer of pressurization continuously, rectifying and purifying system.
5. trichlorosilane pressurization purifying plant, purification tower is a sieve-plate structure, have charging opening on the tower side wall, it is characterized in that: be connected in series in proper order by still kettle, purification tower and overhead water condenser, the steam discharge pipe of still kettle is communicated with purification tower through pipe connecting, the purification tower top is communicated with the overhead water condenser through conduit, and the bottom vent pipe of above-mentioned still kettle and purification tower is communicated with the silicon tetrachloride liquid storage tank, and the liquid discharge pipe of overhead water condenser bottom is communicated with the trichlorosilane storage tank.
6. trichlorosilane pressurization purifying plant according to claim 5, it is characterized in that: the position of charging opening is between the 8th to the 35th block of column plate of purification tower on the above-mentioned purification tower.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005102003344A CN1330569C (en) | 2005-06-16 | 2005-06-16 | Process for pressure purification of silicon trichlorohydrgen and apparatus thereof |
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|---|---|---|---|
| CNB2005102003344A CN1330569C (en) | 2005-06-16 | 2005-06-16 | Process for pressure purification of silicon trichlorohydrgen and apparatus thereof |
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|---|---|
| CN1693192A true CN1693192A (en) | 2005-11-09 |
| CN1330569C CN1330569C (en) | 2007-08-08 |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102101672A (en) * | 2011-01-10 | 2011-06-22 | 华陆工程科技有限责任公司 | Control method for stably adjusting purity of trichlorosilane |
| CN101372335B (en) * | 2007-08-20 | 2011-08-10 | 中国恩菲工程技术有限公司 | Method for preparing polysilicon |
| CN102381712A (en) * | 2011-10-20 | 2012-03-21 | 中国恩菲工程技术有限公司 | Equipment for treating solution containing silicon tetrachloride |
| CN102417182A (en) * | 2011-08-30 | 2012-04-18 | 沁阳市瑞元物资有限公司 | Separation device and method for purifying trichlorosilane in substances with high/low boiling point |
| CN102471074A (en) * | 2009-12-28 | 2012-05-23 | Lg化学株式会社 | Method and apparatus for purification of trichlorosilane |
| CN102502654A (en) * | 2011-10-20 | 2012-06-20 | 中国恩菲工程技术有限公司 | Method for treating solution containing silicon tetrachloride |
| CN101357292B (en) * | 2007-07-31 | 2012-07-04 | 中国恩菲工程技术有限公司 | Method for recovering tail-gas generated during producing polycrystalline silicon using silicon tetrachloride |
| CN105659359A (en) * | 2013-07-26 | 2016-06-08 | 化工技术边界股份有限公司 | Continuous-distillation-type trichlorosilane vaporization supply device and continuous-distillation-type trichlorosilane gas vaporization method |
| CN111153925A (en) * | 2019-12-31 | 2020-05-15 | 江西宏柏新材料股份有限公司 | Device and method for continuously purifying 2-cyanoethyl trichlorosilane |
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| US3516803A (en) * | 1966-10-06 | 1970-06-23 | Texas Instruments Inc | Method for the purification of trichlorosilane |
| US4481178A (en) * | 1982-11-08 | 1984-11-06 | General Electric Company | Purification of chlorosilanes |
| JP4505077B2 (en) * | 1999-04-30 | 2010-07-14 | Ｓｕｍｃｏ Ｔｅｃｈｘｉｖ株式会社 | Trichlorosilane gas vaporizer |
| JP3584218B2 (en) * | 2001-06-07 | 2004-11-04 | 住友チタニウム株式会社 | Chlorosilane purification method |
| CN1222471C (en) * | 2002-10-23 | 2005-10-12 | 同济大学 | Method of producing polysilicon with mixed source of trichloro-hydrosilicon and silicon tetrachloride |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101357292B (en) * | 2007-07-31 | 2012-07-04 | 中国恩菲工程技术有限公司 | Method for recovering tail-gas generated during producing polycrystalline silicon using silicon tetrachloride |
| CN101372335B (en) * | 2007-08-20 | 2011-08-10 | 中国恩菲工程技术有限公司 | Method for preparing polysilicon |
| CN102471074B (en) * | 2009-12-28 | 2014-07-02 | Lg化学株式会社 | Method and apparatus for purification of trichlorosilane |
| CN102471074A (en) * | 2009-12-28 | 2012-05-23 | Lg化学株式会社 | Method and apparatus for purification of trichlorosilane |
| US8535488B2 (en) | 2009-12-28 | 2013-09-17 | Lg Chem, Ltd. | Method and apparatus for purification of trichlorosilane |
| CN102101672A (en) * | 2011-01-10 | 2011-06-22 | 华陆工程科技有限责任公司 | Control method for stably adjusting purity of trichlorosilane |
| CN102417182A (en) * | 2011-08-30 | 2012-04-18 | 沁阳市瑞元物资有限公司 | Separation device and method for purifying trichlorosilane in substances with high/low boiling point |
| CN102502654A (en) * | 2011-10-20 | 2012-06-20 | 中国恩菲工程技术有限公司 | Method for treating solution containing silicon tetrachloride |
| CN102381712A (en) * | 2011-10-20 | 2012-03-21 | 中国恩菲工程技术有限公司 | Equipment for treating solution containing silicon tetrachloride |
| CN105659359A (en) * | 2013-07-26 | 2016-06-08 | 化工技术边界股份有限公司 | Continuous-distillation-type trichlorosilane vaporization supply device and continuous-distillation-type trichlorosilane gas vaporization method |
| CN105659359B (en) * | 2013-07-26 | 2019-05-28 | 化工技术边界股份有限公司 | Continuous still formula trichlorosilane vaporizer/supplier |
| CN111153925A (en) * | 2019-12-31 | 2020-05-15 | 江西宏柏新材料股份有限公司 | Device and method for continuously purifying 2-cyanoethyl trichlorosilane |
| CN111153925B (en) * | 2019-12-31 | 2022-08-12 | 江西宏柏新材料股份有限公司 | Device and method for continuously purifying 2-cyanoethyl trichlorosilane |
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| CN1330569C (en) | 2007-08-08 |
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Assignee: Luoyang Zhonggui High-tech Co., Ltd. Assignor: China Non-ferrous Engineering Design General Inst. Contract fulfillment period: 2007.1.1 to 2016.12.31 contract change Contract record no.: 2008410000161 Denomination of invention: Process for pressure purification of silicon trichlorohydrgen and apparatus thereof Granted publication date: 20070808 License type: Exclusive license Record date: 2008.12.3 |
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Free format text: EXCLUSIVE LICENSE; TIME LIMIT OF IMPLEMENTING CONTACT: 2007.1.1 TO 2016.12.31; CHANGE OF CONTRACT Name of requester: LUOYANG ZHONGGUI HIGH SCIENCE CO., LTD. Effective date: 20081203 |
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Owner name: CHINA YOUSE ENGINEERING CO., LTD. Free format text: FORMER NAME: CHINA NONFERROUS ENGINEERING RESEARCH INSTITUTE |
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Address after: No. 12 Fuxing Road, Beijing, Beijing, Haidian District Patentee after: China Nonferrous Metals Engineering Company Limited Address before: No. 12 Fuxing Road, Beijing, Beijing, Haidian District Patentee before: China Non-ferrous Engineering Design General Inst. |