CN101391772A - Method for preparing solar stage high purify nano silica flour and device system thereof - Google Patents
Method for preparing solar stage high purify nano silica flour and device system thereof Download PDFInfo
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- CN101391772A CN101391772A CNA2007101326677A CN200710132667A CN101391772A CN 101391772 A CN101391772 A CN 101391772A CN A2007101326677 A CNA2007101326677 A CN A2007101326677A CN 200710132667 A CN200710132667 A CN 200710132667A CN 101391772 A CN101391772 A CN 101391772A
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Abstract
The invention provides a method for preparing high-purity nanometer silica fume and an equipment system thereof; the method is a method which adopts a chemical purification method to prepare silica raw materials which provides high quality for the production of solar power grade polycrystalline silicon. The method uses metallurgical grade silicon as a raw material; by crushing, grinding, and drying, silica fume materials with the water content of less than 3 percent and the particle size of 50 to 100nm are obtained; through two-time acid leaching, washing, and drying, high-purity nanometer silica fume is obtained, wherein, the purity of the silicon is over 99.99 percent. In addition, the invention also provides an equipment system which is suitable for the method, mainly comprising a jet mill, a nano-grinding machine, spray-drying equipment, a metering feeder, a reaction kettle, ceramic membrane washing equipment, a purification material collector and the like. The equipment system has the advantages of simplicity, safety, small power consumption, low production cost, high degree of automation of equipment, low human contact rate with materials, as well as stable product quality, is beneficial to human health, and can easily realize large-scale and commercial process.
Description
Technical field
The invention provides a kind of method and device systems thereof for preparing high purify nano silica flour, especially a kind of chemical purification method of using is prepared as the method that solar-grade polysilicon production provides the high quality silicon raw material.
Background technology
The world today, energy problem have become the problem of globalization.The extreme exploitation and the use of fossil energy cause ecological damage and environmental pollution, and the finiteness of fossil energy reserves more and more cause the extensive concern in the world; For the worry to the more and more rampant attack of terrorism, setting up gradually of denuclearization energy mechanism also is that developed country considers one of reason of extensive Renewable Energy Development in the world.Sun power has obtained extensive concern and use as the energy a kind of cleaning, reproducible.On the one hand, the silicon suitable for solar purposes material along with the fast development of photovoltaic industry in this year, has occurred the problem that there is lack of raw materials mainly from the waste material and the substandard products of semi-conductor industry at present.On the other hand, existing chlorination is purified, and to produce solar grade polycrystalline silicon material production technique cost too high and possibility that reduce is little.The begin one's study new production process of solar-grade polysilicon of some experts.
For the health that realizes solar energy industry develops rapidly, according to the performance and the characteristics of industrial silicon, the present invention proposes a kind of low power consuming, less investment, high purity metal silica flour technology of preparing that production cost is low, for the production of solar-grade polysilicon provides high quality raw material.Technical security height, contaminative that the present invention proposes are little, are a kind of eco-friendly green clearer production technologies.
Summary of the invention
The preparation method who the purpose of this invention is to provide a kind of solar stage high purify nano silica flour, promptly adopting metallurgical grade silicon is raw material, through acidleach, cleaning, obtains the high-purity nano silica flour, the purity of its silicon is more than 99.99%.
Another object of the present invention provides a kind of device systems for preparing solar stage high purify nano silica flour, is achieved to guarantee this preparation method.
For realizing above-mentioned first purpose, the preparation method of solar stage high purify nano silica flour provided by the invention may further comprise the steps and condition:
1. pulverize: with metallurgical grade silicon as raw material, adopt pulverizer particularly to adopt micronizer mill, the broken silica flour material that is milled to 50～100 μ m of industrial silicon with 150～840 μ m, the iron contamination that adopts magnet will break in the silica flour of mill back reduces, classified then sieving obtains the following silica flour material of 80 μ m;
2. grind: improved grinding to 50～100nm;
3. dry: the material after the grinding makes its water content be lower than 3% through spraying drying;
4. an acidleach:
Silica flour material after the grinding carries out the acidleach processing with the mixing acid of concentration 1～5mol/L hydrochloric acid and 1～5mol/L nitric acid earlier, and silica flour is 1: 0.5～2.5 (weight ratios) with the adding proportion that leaches acid, and extraction temperature is at 20～80 ℃, and extraction time is 0.5～2 day,
5. washing, drying: clean 5～10 times with the ceramic membrane washing plant then, and silica flour separated with leach liquor and dry.This process is mainly removed iron, aluminium, magnesium, nickel etc., and wherein impurity iron can remove 30～99%; Impurity magnesium can remove 10～99%; Impurity aluminum can remove 30～99%, and impurity nickel can remove 20～98%;
6. secondary pickling:
Employing concentration is that the hydrofluoric acid of 0.5～5mol/L carries out the acidleach processing to the silica flour material, silica flour is 1: 0.5～2.5 (weight ratios) with the adding proportion that leaches acid, extraction temperature is at 20～80 ℃, and extraction time is 0.5～2 day, removes the impurity such as silicon-dioxide in the silica flour.
7. clean with the ceramic membrane washing plant then and be washed till neutrality 3～10 times, and silica flour is separated with leach liquor, silica flour is removed moisture in 80～120 ℃ of following dryings of spray drying device.Material silica flour after the processing, silicone content can reach more than 99.99%, and infusion solution is required to handle discharging according to local environment.
8. pack: treat to pack processing after the material cooling, promptly obtain high-purity silicon powder.
Wherein, micronizer mill can be ground into powder material with lumpy material; Nano-milled machine can grind to form thicker particle nano level powder; Reactor is used for the acid-leaching reaction stage, and the metallic impurity in the silica flour dissolve with acid; The ceramic membrane washing plant be used for the soluble impurity of material after filtration fenestra enter waste water plant, and the bigger silica flour of diameter is retained down, and reaches the purpose of purifying mass; Spraying drying is used for the dry material that finishes that washed.
For realizing above-mentioned second purpose, the present invention has provided a kind of preparation solar stage high purify nano silica flour device systems.Device systems of the present invention includes micronizer mill, nano-milled machine, spray drying device, measurement charging device, reactor, the ceramic membrane washing plant, the purification material collector, wherein micronizer mill [2] discharge port [3] is connected with nano-milled machine [5] opening for feed [4] through transport unit, and discharge port of nano-milled machine [6] and spray drying device I[8] opening for feed [7] be connected, and spray drying device I[8] discharge port [9] through measurement charging device [10] respectively with reactor I[12] opening for feed [11] and reactor II[14] and [13] be connected, the discharge port [15] of the discharge port of reactor I [16] and reactor II is connected with ceramic membrane washing plant [18] opening for feed [17]; Ceramic membrane washing plant discharge port [19] both with spray drying device I[8] opening for feed [7] be connected, again with spray drying device II[21] opening for feed [20] be connected spray drying device II[21] discharge port [22] be connected with purification material collector [23].
The metallurgical grade silicon material enters by feeding unit that micronizer mill is pulverized after transport unit enters nano-milled machine grinds, to prepare nano level silica flour.Silica flour after nano-milled machine wet grinding need enter spray-drier and carry out drying, and dried material joins to contain by measuring apparatus and carries out the pickling purification among a certain amount of mixing acid (hydrochloric acid, nitric acid) reactor I; Its feed liquid enters the ceramic membrane washing plant by pipeline, enter drying among the spray drying device I through washing to neutral back material repeatedly once more by transmission pipeline, entering among the reactor II of hydrofluoric acid containing secondary pickling immediately handles, enter the ceramic membrane washing plant after disposing, enter through deionized water wash that drying promptly obtains the nano level high-purity silicon powder among the spray drying device II in the purification material collector to the neutrality.
Wherein crushing process can adopt micronizer mill to pulverize to grind by nano-milled machine again or directly carry out nano-milled equipment and grind; The ceramic membrane washing plant washs with high purity water or distilled water; Spray drying device also available constant temperature forced air drying equipment or vacuum dryer replace.Nano-milled machine liner agate plate or stainless steel plate; Inner liner of reaction kettle polystyrene or tetrafluoroethylene; Ceramic membrane is to be made by corrosion resistant titanium oxide or zirconium white or aluminum oxide or their mixture, in ceramic membrane equipment, reacts and washs; Spray drying device is to use the spray-dryer of inner liner polytetrafluoroethylene or polystyrene, dry silica flour; Measurement charging device adopts the weight-loss type constant feed weigher on the market, and it mainly is made up of feeding device, the storehouse of weighing, dumping device, LOAD CELLS and microcomputer control system, and this device is used for feed metering and dosing control for enclosed.
Above equipment can not bring pollution and this complete equipment system automation degree height of metallic element to material, and the probability that human body touches objectionable impurities is low, and is low to the human body hazard rating.
The present invention has the following advantages:
1. less investment; 2. equipment is simple, and security is good; 3. current consumption is little, and production cost is low; 4. automation degree of equipment height, human body contact material probability is low, helps HUMAN HEALTH; 5. equipment is realized extensive, suitability for industrialized production, constant product quality easily; 6. environmental pollution is little, is eco-friendly green production process.
Description of drawings
The solar stage high purify nano silica flour preparation method's that Fig. 1 provides for the present invention process flow sheet.
The composition structural representation of the preparation solar stage high purify nano silica flour device systems that Fig. 2 provides for the present invention.
In Fig. 2, the 1st, comminution by gas stream machine inlet capable, the 2nd, micronizer mill, the 3rd, micronizer mill discharge port, the 4th, nano-milled machine inlet capable, the 5th, nano-milled machine, the 6th, nano-milled machine discharge port, the 7th, spray-dryer I opening for feed, the 8th, spray-dryer I, the 9th, spray-dryer I discharge port, the 10th, measurement charging device, the 11st, reactor I opening for feed, the 12nd, reactor I (hydrochloric acid and nitric acid mixing acid), the 13rd, reactor II opening for feed, the 14th, reactor II (hydrofluoric acid), the 15th, reactor II discharge port, the 16th, reactor I discharge port, the 17th, ceramic membrane washing plant opening for feed, the 18th, ceramic membrane washing plant, the 19th, ceramic membrane washing plant discharge port, the 20th, spray-dryer II opening for feed, the 21st, spray-dryer II, the 22nd, spray-dryer II discharge port, the 23rd, purification material collector.
Embodiment:
Describe in further detail below in conjunction with accompanying drawing and embodiment:
Embodiment one:
Using silicone content is that 99.4% metallurgical grade industrial silicon is raw material, its major impurity composition iron level 3300ppm, aluminium content 1500ppm, calcium contents 900ppm.
Raw material after pulverizer [2] is pulverized, is entered nano-milled machine [5] through the material transmitting device and is ground to powder d
50For entering spray-dryer I[8 behind the 100nm] middle dry.Enter reactor I[12 by measurement charging device [10] behind the dry materials] in, mixing acid (1.5mol/L hydrochloric acid: 1.5mol/L nitric acid=1: 1) material particles is carried out acidleach with nitric acid and hydrochloric acid, the adding proportion that makes raw material and mixing acid is 1: 2 (by weight), leaches 1 day in 40～50 ℃ reactor; Feed liquid enters ceramic membrane powder washing plant [18] and cleans 7 times to neutral then, feed liquid after the cleaning enters spray drying device I[8 through transmission pipeline] enter reactor II[14 through measurement charging device [10] once more after the drying] be that the hydrofluoric acid of 2.5mol/L carries out secondary pickling processing (raw material: hydrofluoric acid=1: 2 with concentration, by weight), 40～50 ℃ reactor internal reactions 0.5 day, the impurity such as silicon-dioxide of silicon face are removed and cleaned 7 times to neutral with ceramic membrane powder washing plant [18].And leach liquor separated with silica flour, wherein infusion solution requires to handle discharging, silica flour spray drying device II[21 according to local environment] remove moisture 100 ℃ of following dryings.Silica flour enters purification material collector [23] after the drying treatment, and silicone content is 99.9912% in the silica flour.
Embodiment two:
Using silicone content is that 99.5% metallurgical grade industrial silicon is raw material, its major impurity composition iron level 1800ppm, aluminium content 1500ppm, calcium contents 620ppm.
After raw material usefulness pulverizer [2] pulverizing, enter nano-milled machine [5] through the material transmitting device and grind, make the d of powder
50=50nm enters in the spray drying device [8] dry to material then.Dried material enters reactor I[12 by measurement charging device [10]] in, use mixing acid (the 3mol/L hydrochloric acid: 3mol/L nitric acid=1: 1) material particles is carried out acidleach (material: mixing acid=1: 2 of nitric acid and hydrochloric acid then, by weight), in 50～70 ℃ reactor, leached 1 day, feed liquid enters ceramic membrane powder washing plant [18] and cleans 7 times to neutral then, feed liquid after the cleaning enters spray drying device I[8 through transmission pipeline] after the drying, material enters reactor II[14 through measurement charging device [10] once more] be that the hydrofluoric acid of 3.5mol/L carries out secondary pickling and handles (material: hydrofluoric acid=1: 2 with concentration, by weight), 50～70 ℃ reactor internal reactions 1 day, the impurity such as silicon-dioxide of silicon face are removed; And clean 7 times with ceramic membrane powder washing plant [18] and make it to neutrality.Separate leach liquor and silica flour then, wherein infusion solution required to handle discharging, silica flour spray drying device II[21 according to local environment] remove moisture 100 ℃ of following dryings.Silica flour enters purification material collector [23] after the spray drying treatment, and silicone content is 99.9962% in the silica flour.
Claims (8)
1. the preparation method of a solar stage high purify nano silica flour, it is characterized in that: this preparation method may further comprise the steps:
(1) pulverize: with metallurgical grade silicon as raw material, adopt pulverizer particularly to adopt micronizer mill, the broken silica flour material that is milled to 50～100 μ m of industrial silicon with 150～840 μ m, the iron contamination that adopts magnet will break in the silica flour of mill back reduces, classified then sieving obtains the following silica flour material of 80 μ m;
(2) grind: improved grinding to 50～100nm;
(3) drying: the material after the grinding makes its water content be lower than 3% through spraying drying;
(4) acidleach: the silica flour material after the grinding carries out the acidleach processing with the mixing acid of concentration 1～5mol/L hydrochloric acid and 1～5mol/L nitric acid earlier, wherein silica flour is 1: 0.5～2.5 (weight ratios) with the adding proportion that leaches acid, extraction temperature is at 20～80 ℃, and extraction time is 0.5～2 day;
(5) washing, drying: clean 5～10 times with the ceramic membrane washing plant then, and silica flour is separated with leach liquor and drying;
(6) secondary pickling: employing concentration is that the hydrofluoric acid of 0.5～5mol/L carries out the acidleach processing once more to the silica flour material, silica flour is 1: 0.5～2.5 (weight ratios) with the adding proportion that leaches acid, extraction temperature is at 20～80 ℃, extraction time is 0.5～2 day, removes the impurity such as silicon-dioxide in the silica flour;
(7) washing, drying: clean with the ceramic membrane washing plant then and be washed till neutrality 3～10 times, and silica flour is separated with leach liquor, silica flour is removed moisture in 80～120 ℃ of following dryings of spray drying device;
(8) packing: the material silica flour after the processing, silicone content reaches more than 99.99%, treats to pack processing after the material cooling, promptly obtains high-purity silicon powder.
2. the preparation method of solar stage high purify nano silica flour according to claim 1, it is characterized in that: described raw material is the metallurgical grade industrial silicon of purity 98～99.5%.
3. the preparation method of solar stage high purify nano silica flour according to claim 1, it is characterized in that: the ceramic membrane washing plant washs with high purity water or distilled water.
4. device systems for preparing solar stage high purify nano silica flour, it is characterized in that: described device systems includes micronizer mill, nano-milled machine, spray drying device, measurement charging device, reactor, the ceramic membrane washing plant, the purification material collector, wherein micronizer mill [2] discharge port [3] is connected with nano-milled machine [5] opening for feed [4], and discharge port of nano-milled machine [6] and spray drying device I[8] opening for feed [7] be connected, and spray drying device I[8] discharge port [9] by measurement charging device [10] and reactor I[12] and reactor II[14] opening for feed [11] and [13] are connected, the discharge port [16] of reactor I and reactor II and [15] are connected with ceramic membrane washing plant [18] opening for feed [17]; Ceramic membrane washing plant discharge port [19] both with spray drying device I[8] opening for feed [7] be connected, again with spray drying device II[21] opening for feed [20] be connected spray drying device II[21] discharge port [22] be connected with purification material collector [23].
5. the device systems of preparation solar stage high purify nano silica flour according to claim 4, it is characterized in that: described nano-milled machine uses inner liner polytetrafluoroethylene plate or agate plate or polystyrene board or stainless steel plate, and opening for feed and discharge port are made by tetrafluoroethylene or polypropylene or polyethylene.
6. the device systems of preparation solar stage high purify nano silica flour according to claim 4, it is characterized in that: described spray drying device is to use the spray-dryer of inner liner polytetrafluoroethylene or polystyrene, and described spray drying device can replace with constant temperature forced air drying equipment or vacuum dryer.
7. the device systems of preparation solar stage high purify nano silica flour according to claim 4 is characterized in that: ceramic membrane is to be made by corrosion resistant titanium oxide or zirconium white or aluminum oxide or their mixture in the described ceramic membrane washing plant.
8. the device systems of preparation solar stage high purify nano silica flour according to claim 4 is characterized in that: described inner liner of reaction kettle tetrafluoroethylene or polystyrene or polypropylene.
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101886012A (en) * | 2009-05-13 | 2010-11-17 | 通用电气公司 | Process for obtaining treated coal and silica from coal containing fly ash |
| WO2012071640A1 (en) * | 2010-12-01 | 2012-06-07 | Barra Do Guaicuí S.A. | A method for producing high-purity metallurgical-grade silicon metal by means of purification with metals and other compounds, followed by leaching |
| CN102951644A (en) * | 2012-11-20 | 2013-03-06 | 昆明理工大学 | Antifoaming method for preparing upgrade metallurgical grade silicon from industrial silicon |
| TWI551538B (en) * | 2013-07-10 | 2016-10-01 | 國立臺灣大學 | Method of separating nano-materials |
| CN109037665A (en) * | 2018-07-10 | 2018-12-18 | 郑州中科新兴产业技术研究院 | A method of nano-silicon negative electrode material is prepared using photovoltaic industry waste silicon residue |
| CN110040734A (en) * | 2019-03-15 | 2019-07-23 | 深圳市动力创新科技企业（有限合伙） | A kind of nano-silicon and preparation method thereof |
| CN110129892A (en) * | 2019-06-03 | 2019-08-16 | 西安奕斯伟硅片技术有限公司 | Reduce the method for silico briquette surface organic matter and the preparation method of monocrystalline silicon |
| CN110890537A (en) * | 2018-09-11 | 2020-03-17 | 江苏中能硅业科技发展有限公司 | Production method of high-purity nanocrystalline silicon |
-
2007
- 2007-09-18 CN CNA2007101326677A patent/CN101391772A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101886012A (en) * | 2009-05-13 | 2010-11-17 | 通用电气公司 | Process for obtaining treated coal and silica from coal containing fly ash |
| WO2012071640A1 (en) * | 2010-12-01 | 2012-06-07 | Barra Do Guaicuí S.A. | A method for producing high-purity metallurgical-grade silicon metal by means of purification with metals and other compounds, followed by leaching |
| CN102951644A (en) * | 2012-11-20 | 2013-03-06 | 昆明理工大学 | Antifoaming method for preparing upgrade metallurgical grade silicon from industrial silicon |
| TWI551538B (en) * | 2013-07-10 | 2016-10-01 | 國立臺灣大學 | Method of separating nano-materials |
| CN109037665A (en) * | 2018-07-10 | 2018-12-18 | 郑州中科新兴产业技术研究院 | A method of nano-silicon negative electrode material is prepared using photovoltaic industry waste silicon residue |
| CN109037665B (en) * | 2018-07-10 | 2019-10-15 | 郑州中科新兴产业技术研究院 | A method of nano-silicon negative electrode material is prepared using photovoltaic industry waste silicon residue |
| CN110890537A (en) * | 2018-09-11 | 2020-03-17 | 江苏中能硅业科技发展有限公司 | Production method of high-purity nanocrystalline silicon |
| CN110040734A (en) * | 2019-03-15 | 2019-07-23 | 深圳市动力创新科技企业（有限合伙） | A kind of nano-silicon and preparation method thereof |
| CN110129892A (en) * | 2019-06-03 | 2019-08-16 | 西安奕斯伟硅片技术有限公司 | Reduce the method for silico briquette surface organic matter and the preparation method of monocrystalline silicon |
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