CN1392101A - Process for producing nano calcium carbonate by ultrasonic cavitation technology - Google Patents
Process for producing nano calcium carbonate by ultrasonic cavitation technology Download PDFInfo
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- CN1392101A CN1392101A CN 02136278 CN02136278A CN1392101A CN 1392101 A CN1392101 A CN 1392101A CN 02136278 CN02136278 CN 02136278 CN 02136278 A CN02136278 A CN 02136278A CN 1392101 A CN1392101 A CN 1392101A
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- calcium carbonate
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Abstract
The present invention relates to the production process of calcium carbonate, and especially one ultrasonic cavitation process of producing nano calcium carbonate. The present invention solves the problem of slow mass transferring rate among gas, liquid and solid phases. The production process includes calcining limestone in a vertical kiln to obtain CaO and CO2, hydration of CaO in a digestor to obtain Ca(OH)2, carbonation of Ca(OH)2 emulsion with kiln gas CO2 in a reactor to obtain superfine CaCO3, the CaCO3 slurry is spray dried to obtain superfine calcium arbonate powder, and the ultrasonic cavitation treatment during hydration, preparing slurry and carbonation in separate ultrasonic crusher. Each ultrasonic crusher has power of 6100-7000 w, frequency of 15-19 KHz and 8-16 emitters provided.
Description
One, technical field
The present invention relates to the production method of lime carbonate, particularly a kind of ultrasonic cavitation physical influence is pulverized the method with chemical reaction engineering bonded producing nano calcium carbonate by ultrasonic cavitation technology.
Two, background technology
At present, produce the method for calcium carbonate superfine powder both at home and abroad, adopt usually carbon dioxide is fed the reactor that fills calcium hydroxide emulsion, in carburizing reagent, add the crystalline form growth control agent, obtain calcium carbonate superfine powder.Referring to Chinese patent ZL93108625.6, Japanese Patent 93228730, Japanese Patent 93221634, the production method of this calcium carbonate superfine powder is disclosed, because single chemical method is in carburizing reagent, make the alternate rate of mass transfer of gas, liquid, solid slower, easily produce particle parcel phenomenon, cause reaction not exclusively, granular size is inhomogeneous, carbonization time is long, production efficiency is low, can not form large-scale industrial production.Another piece british patent document GB1074099 " a kind of production method of pure whiting of improvement " has introduced a kind of with utilizing hyperacoustic vibrotechnique to produce lime carbonate under the pressure, during carburizing reagent, bottom end at high-pressure reactor is carried out ultrasonic vibration, this method exists the alternate rate of mass transfer of gas, liquid, solid slower equally, easily producing particle parcel phenomenon, only is micron order lime carbonate.Chinese patent ZL99127024.x has introduced a kind of " process for preparing nm-class calcium carbonate by ultrasonic cavitation technique ", but lacks the enforcement feature in this application, makes those skilled in the art can't implement this invention.
Three, summary of the invention
The technical issues that need to address of the present invention are: under not additivated situation, how to utilize the pulverizing of ultrasonic cavitation physical influence to combine production with chemical engineering and obtain the even particle size distribution nano-calcium carbonate.The carbonation reaction time shortens, and the microcosmic of carbonization process mixes and the microcosmic mass transfer is strengthened.
Technical scheme of the present invention is: the method for producing nano calcium carbonate by ultrasonic cavitation technology, comprise Wingdale process calcining in shaft kiln, and obtain unslaked lime CaO and CO
2, CaO carries out hydration in digestive organ, the Ca that obtains (OH)
2Emulsion adds kiln gas CO in reactor
2Carry out carbonization, obtain ultra-fine CaCO after the reaction
3Slurries are spray dried to nano-powder material, the CaO hydration of carrying out behind limestone calcination, Ca (OH)
2The ultrasonic cavitation processing is carried out in slurrying and carbonization simultaneously, it is characterized in that: the CaO hydration of carrying out, Ca (OH)
2A ultrasonic grinding instrument is all disposed in slurrying and carbonization, ultrasonic power is 6100W-7000W, and operating frequency is 15-19KHZ/ second, every ultrasonic grinding instrument configuration projector 8-16 cover, the 30-60 minute ultrasonic cavitation time during CaO hydration, the emulsion granules particle diameter≤1um that obtains; Ca (OH)
220-50 minute ultrasonic cavitation time during slurrying, the emulsion granules particle diameter≤0.5um that obtains; Feed carbon dioxide during carburizing reagent, carbon dioxide air source adopts the carbonic acid gas after Wingdale is calcined in shaft kiln, contain 30-40%CO
2, gas flow is 15-35m
3/ minute, carry out carburizing reagent, ultrasonic cavitation continues 20-50 minute, becomes 7 until the emulsion pH value, and through dehydrating, 120 ℃-280 ℃ of drying temperatures obtain the nano-calcium carbonate powder product, the particle diameter 20-100nm of Nano particles of calcium carbonate, specific surface area is greater than 22m
2/ g.
Ultrasonic grinding instrument and supporting projector are commercially available standard prod, and the projector upper end is furnished with the stainless steel long tube of sealing, and long tube must be drawn outside the equipment, and the cable of projector is drawn by the pipe endoporus and connected the ultrasonic grinding instrument.The fixedly wire net frame of projector is installed, is set in the present invention and must joins on the equipment inwall of ultrasonic grinding instrument and the inwall between the stir shaft fixingly, evenly be immersed under the liquid level apart from about 1 meter between the upper and lower.Method of the present invention does not have particular requirement to carbonation reaction temperature, but with 20 ℃-30 ℃ for well.
The invention has the beneficial effects as follows: the CaO hydration of behind limestone calcination, carrying out, Ca (OH)
2Carrying out ultrasonic cavitation in the time of slurrying and carbonation reaction handles, the projector of preparation, when in normal pressure operating mode and stable state liquid, working, when the ultrasonic wave that generates is propagated in liquid, because the influence of powerful acoustic pressure effect, produce the density district, and negative pressure produces many cavitys in medium, cavity expands along with pressure, blast, the vacuum chamber explosion time produces instantaneous pressure, to reach several thousand and even up to ten thousand normal atmosphere, the vacuum chamber blast is the outburst of atmospheric energy, has the intensive mechanics, calorifics, chemistry, a series of cavitation physical influences such as electricity and effect, to constantly make particle matter layer loosening, peel off, pulverize, reach refinement particulate effect, the air-flow that cavity produces is constantly eliminated gas, liquid, hand over the frictional belt of attitude face between solid phase, quicken gas, liquid, rate of mass transfer between solid phase and chemical reaction rate, because the promotion of air-flow makes constantly collision mutually of particle, eliminate the particle parcel thus and reunite, make reaction thoroughly.Handle the particle diameter 20-100 nanometer of the particle of the lime carbonate that obtains through three ultrasonic cavitations in the production process.Technology of the present invention is produced nano-calcium carbonate with single chemical method and is compared, has process innovation, novel in design, easy to operate, product performance are stable, and preparation time shortens 5-30 doubly than single chemical method, production cost is low, the efficient height is convenient to computer and is controlled automatically, is the desirable processing technology of large-scale industrial production nm-class active calcium carbonate product.
Four, description of drawings Fig. 1 is that ultrasonic grinding instrument of the present invention and supporting projector installation schematic front view Fig. 2 in the carburizing reagent still are among ultrasonic grinding instrument of the present invention and the installation sectional top view figure of supporting projector in the carburizing reagent still: the 1-reactor, the 2-valve, the 3-air valve, the 4-gas distribution grid, 5-is the wire net frame fixedly, the 6-projector, the 7-pipe
Five, embodiment
Embodiment 1: Wingdale through 1100 ℃ of calcinings, obtains calcium oxide and carbon dioxide at shaft kiln, and carbonic acid gas is sent into the carbonic acid gas gas-holder through induced draft fan, claims 10 tons in 1 ton in calcium oxide and water, hydration in digestive organ, and the digestive organ volume is 20m
3Join 1 in ultrasonic grinding instrument, ultrasonic grinding instrument and supporting waterproof type projector product type are: SC-7000W, and the projector upper end is furnished with the stainless steel long tube of sealing, long tube must be drawn outside the equipment, and the cable of projector is drawn by the pipe endoporus and connected the ultrasonic grinding instrument.The fixedly wire net frame of projector is installed, is set in this technology and must joins on the inwall between hyperacoustic equipment inwall and the stir shaft fixingly, evenly be immersed under the liquid level apart from about 1 meter between the upper and lower.Ultrasonic grinding instrument power is 6400W, and operating frequency is 19KHZ/ second, and 8 cover projectors fixedly carried out ultrasonic cavitation 50 minutes on the wire net frame in digester plant.Make particle pulverize the back particle diameter and be not more than 1um, the removal of impurity is after filtration sent into lime water slurry jar by liquid-feeding pump, and liquid slurry tank volume is 20m
3, join 1 in ultrasonic grinding instrument, power is 6400W, and operating frequency is 19KHZ/ second, and 8 cover projectors fixedly carried out ultrasonic cavitation 40 minutes on the wire net frame at liquid slurry jar equipment, made particle pulverize the back particle diameter and were not more than 0.5um.Remove impurity after filtration, emulsion is sent into carburizing reagent still 1 by liquid-feeding pump.Reactor 1 volume is 18m
3, carbonation reaction temperature is 28 ℃, the carbon dioxide air source gas-holder, and compressed machine is sent into reactor, contains the air gas mixture of 32% carbonic acid gas.The air gas mixture flow is 28m
3/ minute, when feeding carbon dioxide reaction, carry out ultrasonic cavitation, with reference to accompanying drawing 1,2 (ultrasonic grinding instrument and supporting projector are at digestive organ and liquid slurry jar installation site and accompanying drawing 1,2 is identical), join 1 in ultrasonic grinding instrument, power is 6400W, operating frequency is 19KHZ/ second, emulsion enters reactor 1 by valve 2, carbonic acid gas enters gas distribution grid 4 by air valve 3, and fixedly wire net frame 5 is positioned in the middle of the reactor 1 inwall liquid level and is fixed on the inwall, and 8 cover projectors 6 are positioned at fixedly on the wire net frame 5, the projector cable is connected ultrasonic grinding instrument interface by drawing in the pipe 7, feed carbonic acid gas and continue ultrasonic cavitation 30 minutes, make the emulsion pH value become 7, obtain the nano-calcium carbonate slurries and send into spray drying device by liquid-feeding pump, drying temperature is 150 ℃, obtains the nano-calcium carbonate powder product.Send into packaging facilities by conveyer, after packing, obtain 1.5 tons of nm-class active calcium carbonate products.Sampling send Shanghai Institute of Measurement and Testing Technology to detect: particle diameter is 40 nanometers, and specific surface area is 22.4m
2/ g.
During embodiment 2:CaO hydration, ultrasonic power is 6600W, operating frequency 17KHZ/ second, 12 40 minutes projector cavitation times of cover of preparation; Ca (OH)
2During slurrying, ultrasonic power is 6600W, operating frequency 17KHZ/ second, 12 30 minutes projector cavitation times of cover of preparation; When carburizing reagent, ultrasonic power is 6600W, operating frequency 17KHZ/ second contains the air gas mixture of 35% carbonic acid gas, and mixed gas flow is 22m
3/ minute, 25 ℃ of carbonation reaction temperatures.Preparation 12 cover projectors carried out ultrasonic cavitation 35 minutes, and drying temperature is 200 ℃.Other are all identical with embodiment 1, and it is 32 nanometers that scanning electron microscopic observation crystalline form, median size are used in sampling, and fineness ratio is 1: 10-15.
During embodiment 3:CaO hydration, ultrasonic power is 6800W, operating frequency 16KHZ/ second, 14 35 minutes projector cavitation times of cover of preparation; Ca (OH)
2During slurrying, ultrasonic power is 6800W, operating frequency 16KHZ/ second, 14 25 minutes projector cavitation times of cover of preparation; When carburizing reagent, ultrasonic power is 6800W, operating frequency 16KHZ/ second contains the air gas mixture of 38% carbonic acid gas, and mixed gas flow is 33m
3/ minute, 22 ℃ of carbonation reaction temperatures.Preparation 14 cover projectors carried out ultrasonic cavitation 25 minutes, and drying temperature is 240 ℃.Other are all identical with embodiment 1, and it is 28 nanometers that scanning electron microscopic observation crystalline form, median size are used in sampling, and fineness ratio is 1: 9-17.
Claims (9)
1, the method for producing nano calcium carbonate by ultrasonic cavitation technology comprises Wingdale process calcining in shaft kiln, obtains unslaked lime CaO and CO
2, CaO carries out hydration in digestive organ, the Ca that obtains (OH)
2Emulsion adds kiln gas CO in reactor
2Carry out carbonization, reacted ultra-fine CaCO
3Slurries are spray dried to nano-powder material, the CaO hydration of carrying out behind limestone calcination, Ca (OH)
2Carry out ultrasonic cavitation in the time of slurrying and carbonation reaction and handle, it is characterized in that: the CaO hydration of carrying out, Ca (OH)
2A ultrasonic grinding instrument is all disposed in slurrying and carburizing reagent, and ultrasonic power is 6100W-7000W, and operating frequency is 15-19KHZ/ second, every ultrasonic grinding instrument configuration projector 8-16 cover.
2, the method for producing nano calcium carbonate by ultrasonic cavitation technology according to claim 1 is characterized in that: 30-60 minute ultrasonic cavitation time during the CaO hydration, 20-50 minute ultrasonic cavitation time during slurrying, carburizing reagent ultrasonic cavitation time 20-50 minute.
3, the method for producing nano calcium carbonate by ultrasonic cavitation technology according to claim 1 is characterized in that: emulsion granules particle diameter≤1um that the CaO hydration obtains at last.
4, the method for producing nano calcium carbonate by ultrasonic cavitation technology according to claim 1 is characterized in that: Ca (OH)
2Emulsion granules particle diameter≤the 0.5um that obtains at last during slurrying.
5, the method for producing nano calcium carbonate by ultrasonic cavitation technology according to claim 1 and 2 is characterized in that: feed carbon dioxide during carburizing reagent, gas flow is 15-35m
3/ minute, carry out carburizing reagent, become 7 until the emulsion pH value, through dehydrating, 120 ℃-280 ℃ of drying temperatures obtain the nano-calcium carbonate powder product.
6, the method for producing nano calcium carbonate by ultrasonic cavitation technology according to claim 5 is characterized in that: described carbon dioxide air source adopts the carbonic acid gas after Wingdale is calcined in shaft kiln, contain 30-40%CO
2
7, the method for producing nano calcium carbonate by ultrasonic cavitation technology according to claim 5 is characterized in that: carbonation reaction temperature is preferably 20 ℃-30 ℃.
8, the method for producing nano calcium carbonate by ultrasonic cavitation technology according to claim 5 is characterized in that: the particle diameter 20-100nm of the Nano particles of calcium carbonate that obtains, specific surface area is greater than 22m
2/ g.
9, a kind of ultrasonic grinding instrument that is used for the method for the described producing nano calcium carbonate by ultrasonic cavitation technology of claim 1, be standard prod, the projector upper end is furnished with the stainless steel long tube of sealing, long tube must be drawn outside the equipment, the cable of projector is drawn by the pipe endoporus and is connected the ultrasonic grinding instrument, it is characterized in that: the fixedly wire net frame of projector is installed, is set in this technology and must joins on the inwall between hyperacoustic equipment inwall and the stir shaft fixingly, evenly be immersed under the liquid level apart from about 1 meter between the upper and lower.
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| CNB021362785A CN1164495C (en) | 2002-07-29 | 2002-07-29 | Process for producing nano calcium carbonate by ultrasonic cavitation technology |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009083633A1 (en) * | 2007-12-14 | 2009-07-09 | Timo Olavi Imppola | A method and apparatus to produce precipitated calcium carbonate |
| CN103738996A (en) * | 2013-12-13 | 2014-04-23 | 绵阳市远达新材料有限公司 | Nano barium carbonate preparation method |
| CN104477961A (en) * | 2014-12-22 | 2015-04-01 | 南通市飞宇精细化学品有限公司 | Preparation method of high-purity fine calcium carbonate |
| JP2015199654A (en) * | 2014-03-31 | 2015-11-12 | 日本製紙株式会社 | Production method of calcium carbonate |
| CN106360736A (en) * | 2016-08-22 | 2017-02-01 | 青岛食安生物工程有限公司 | Preparation technology of pure natural nanometer ultrafine calcium powder |
| CN106830042A (en) * | 2017-03-01 | 2017-06-13 | 西安科技大学 | The method that a kind of utilization Weihe north Ordovician limestone prepares the ultra-fine carbonic acid fine particle calcium carbonate of rhombohedron shape |
| CN107902687A (en) * | 2017-12-15 | 2018-04-13 | 柳州吉辉机械设计有限公司 | A kind of method that precipitated calcium carbonate is prepared with gangue |
| CN107915247A (en) * | 2017-12-15 | 2018-04-17 | 柳州吉辉机械设计有限公司 | A kind of method with coal ash for manufacturing for precipitated calcium carbonate |
| CN108002419A (en) * | 2017-12-15 | 2018-05-08 | 柳州吉辉机械设计有限公司 | A kind of method that precipitated calcium carbonate is prepared with Dali rock ballast |
| CN108033474A (en) * | 2017-12-15 | 2018-05-15 | 柳州吉辉机械设计有限公司 | A kind of method that precipitated calcium carbonate is prepared with blast-furnace cinder |
| CN109689574A (en) * | 2016-07-25 | 2019-04-26 | Omya国际股份公司 | The production of amorphous calcium carbonate |
| CN111017973A (en) * | 2019-12-18 | 2020-04-17 | 东莞理工学院 | Method for preparing hollow nano calcium carbonate by using ultrasonic aerosol |
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| CN109925904A (en) * | 2019-04-01 | 2019-06-25 | 清华大学 | The method for preparing ultra-fine alkaline absorbent slurries using ultrasonic wave |
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2002
- 2002-07-29 CN CNB021362785A patent/CN1164495C/en not_active Expired - Fee Related
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009083633A1 (en) * | 2007-12-14 | 2009-07-09 | Timo Olavi Imppola | A method and apparatus to produce precipitated calcium carbonate |
| CN103738996A (en) * | 2013-12-13 | 2014-04-23 | 绵阳市远达新材料有限公司 | Nano barium carbonate preparation method |
| CN103738996B (en) * | 2013-12-13 | 2015-07-01 | 绵阳市远达新材料有限公司 | Nano barium carbonate preparation method |
| JP2015199654A (en) * | 2014-03-31 | 2015-11-12 | 日本製紙株式会社 | Production method of calcium carbonate |
| CN104477961A (en) * | 2014-12-22 | 2015-04-01 | 南通市飞宇精细化学品有限公司 | Preparation method of high-purity fine calcium carbonate |
| CN109689574A (en) * | 2016-07-25 | 2019-04-26 | Omya国际股份公司 | The production of amorphous calcium carbonate |
| CN106360736A (en) * | 2016-08-22 | 2017-02-01 | 青岛食安生物工程有限公司 | Preparation technology of pure natural nanometer ultrafine calcium powder |
| CN106830042A (en) * | 2017-03-01 | 2017-06-13 | 西安科技大学 | The method that a kind of utilization Weihe north Ordovician limestone prepares the ultra-fine carbonic acid fine particle calcium carbonate of rhombohedron shape |
| CN106830042B (en) * | 2017-03-01 | 2018-05-11 | 西安科技大学 | A kind of method that the ultra-fine carbonic acid fine particle calcium carbonate of rhombohedron shape is prepared using Weihe north Ordovician limestone |
| CN107915247A (en) * | 2017-12-15 | 2018-04-17 | 柳州吉辉机械设计有限公司 | A kind of method with coal ash for manufacturing for precipitated calcium carbonate |
| CN108002419A (en) * | 2017-12-15 | 2018-05-08 | 柳州吉辉机械设计有限公司 | A kind of method that precipitated calcium carbonate is prepared with Dali rock ballast |
| CN108033474A (en) * | 2017-12-15 | 2018-05-15 | 柳州吉辉机械设计有限公司 | A kind of method that precipitated calcium carbonate is prepared with blast-furnace cinder |
| CN107902687A (en) * | 2017-12-15 | 2018-04-13 | 柳州吉辉机械设计有限公司 | A kind of method that precipitated calcium carbonate is prepared with gangue |
| CN111017973A (en) * | 2019-12-18 | 2020-04-17 | 东莞理工学院 | Method for preparing hollow nano calcium carbonate by using ultrasonic aerosol |
| CN111017973B (en) * | 2019-12-18 | 2022-05-17 | 东莞理工学院 | Method for preparing hollow nano calcium carbonate by using ultrasonic aerosol |
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