CN112938996A - Whitening process method of quartz sand/powder - Google Patents
Whitening process method of quartz sand/powder Download PDFInfo
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- CN112938996A CN112938996A CN202110382225.8A CN202110382225A CN112938996A CN 112938996 A CN112938996 A CN 112938996A CN 202110382225 A CN202110382225 A CN 202110382225A CN 112938996 A CN112938996 A CN 112938996A
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/113—Silicon oxides; Hydrates thereof
- C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
- C01B33/18—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
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Abstract
The invention discloses a whitening process method of quartz sand/powder, which comprises the steps of firstly, uniformly stirring and mixing a quartz sand raw material with the particle size of 26-150 meshes or a quartz powder raw material with the fineness of more than or equal to 325 meshes and a mineralizer to form a mixture; and calcining the mixture at 1050-1550 ℃, preserving heat for 10-180 minutes, and cooling to obtain whitened quartz sand or whitened quartz powder. The invention leads the quartz sand (powder) to generate a series of physical and chemical reactions under the action of the mineralizer under the high temperature condition by introducing the mineralizer, thus obviously improving the whiteness value of the quartz sand (powder). The method has the advantages of simple process, low cost, environmental protection, high whiteness of the obtained quartz sand (powder), less mottle, suitability for the high-quality plate industry, and capability of well meeting the market demand for the high-quality and high-whiteness quartz sand (powder).
Description
Technical Field
The invention relates to the technical field of an electrodeless material, in particular to a quartz sand/powder whitening process method.
Background
The quartz sand/powder crystal has stable structure, excellent physical and chemical properties, higher hardness, and strong weather resistance and corrosion resistance. Based on these excellent properties, and the huge storage capacity and low price of quartz on the earth, quartz sand/powder is widely used in the fields of glass, ceramics, paper making, artificial quartz plates, functional materials, high-performance composite material fillers, high-performance ceramics and the like. However, since natural quartz contains various impurities, the appearance color shows white, off-white, yellow, black, red, etc. according to the impurities, so that the quartz sand (powder) processed by a simple mechanical processing method is difficult to meet the development requirements of various industries of national economy. Particularly, in quartz stone plates and natural deposits, quartz with high whiteness and less impurities is less and less, the whiteness of quartz sand (powder) is improved by various technical methods, and the quartz sand (powder) is used for producing high-whiteness quartz stone products, meets the market demand on high-grade quartz stone products, and has direct practical significance. In the industries of coatings, plastics and rubber products, the quartz powder with good whiteness can also be used for producing high-quality coatings with high cost performance and high-quality plastics and rubber products;
at present, the process methods for producing quartz sand (powder) in large scale mainly comprise the following steps:
(1) directly crushing and grinding. The method is mainly used for producing common sand (powder) for glass, sand (powder) for ceramic industry, molding sand for casting industry and the like, and the quartz sand produced by the processing method is low in price and very large in consumption.
(2) After crushing and ball milling, magnetic separation equipment and desliming equipment are added, and the processing method is mainly used for producing glass sand or quartz plate sand with different grades. The content of silicon in the glass sand is generally required to be more than 99 percent, and the grade is divided into different grades of 200PPM, 100PPM, 80PPM, 50PPM and the like according to the content of ferric oxide in the product. The plate sand has no strict requirements on the silicon content, but has specific requirements on the granularity and the appearance whiteness of quartz sand (powder) and the content of variegated colors in the sand. As the natural quartz sand inevitably contains yellow skin and black spots, and the impurities are combined with quartz sand particles, the production method of magnetic separation and desliming is difficult to produce pure white quartz sand for high-grade plates. Even the silica sand with very low iron content and the silica sand with very high grade used in the glass industry are difficult to meet the requirements in the plate industry.
(3) After crushing and ball milling, an acid washing procedure is added. The process method is combined with color selection, and can produce the pure white plate sand with whiteness higher than 80 degrees and very few black spots. However, the process uses the composite acid, which has different influences on the health of workers and the environmental sanitation. Moreover, if the production process is not strictly controlled, the residual acid will also have a certain effect on the quality of the board, for example, causing the late yellowing of the board. Currently, this process has not been allowed to continue in Guangdong province.
In conclusion, how to produce high-grade high-whiteness quartz sand (powder) which can meet the market demand, especially the demand of the plate industry from the existing natural quartz sand stone through a scientific and environment-friendly production process is a problem which needs to be solved urgently.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide the whitening process method of the quartz sand/powder, which has the advantages of simple process, low cost, environmental protection and capability of obviously improving the whiteness, so as to obtain the quartz sand (powder) which has high whiteness and few mottle and is suitable for high-quality plates, thereby meeting the market demand on the high-quality and high-whiteness quartz sand (powder).
The purpose of the invention is realized by the following technical scheme:
the invention provides a quartz sand/powder whitening process method, which comprises the following steps:
(1) mixing quartz sand raw materials with the particle size of 26-150 meshes or quartz powder raw materials with the fineness of more than or equal to 325 meshes with a mineralizer by stirring to form a mixture; wherein the amount of the mineralizer is 0.1-2.0 wt% of the quartz sand raw material or the quartz powder raw material;
(2) and calcining the mixture at 1050-1550 ℃, preserving heat for 10-180 minutes, and cooling to obtain a quartz sand calcined material or a quartz powder calcined material, namely the whitened quartz sand or whitened quartz powder.
Further, the quartz sand after whitening is subjected to magnetic separation and/or color separation to remove impurity color particles, so that the high-whiteness quartz sand is obtained. Or grinding the whitened quartz sand by using a grinding device to obtain whitened quartz powder with the fineness of more than or equal to 325 meshes.
Further, the high-whiteness quartz sand is ground by a grinding device to obtain high-whiteness quartz powder with the fineness of more than or equal to 325 meshes.
In the above scheme, the mineralizer is one or a combination of calcium fluoride, sodium silicate, sodium fluoride, sodium carbonate, potassium fluoride, potassium carbonate, lithium fluoride, lithium carbonate, sodium acetate, lithium acetate, sodium pyrophosphate, trisodium phosphate, sodium tripolyphosphate, sodium hexametaphosphate and lithium phosphate.
In the scheme, the blue light whiteness value of the quartz sand raw material or the quartz powder raw material is 60-76 degrees. The blue light whiteness value of the high-whiteness quartz sand is 80-100 degrees.
In the scheme, the stirring and mixing mode in the step (1) is dry mixing or wet mixing; the wet mixing mode is that water, quartz sand raw material or quartz powder raw material and mineralizer are added additionally to be stirred and mixed, and then the mixture is formed after drying.
The invention has the following beneficial effects:
(1) according to the invention, a proper mineralizer is introduced, so that a series of physical and chemical reactions are generated under the action of the mineralizer on the quartz sand (powder) at a high temperature, and the whiteness value of the quartz sand (powder) is obviously improved (the blue light whiteness value of the quartz sand (powder) treated by the process method disclosed by the invention reaches 80-100 ℃). Among them, the most important physicochemical reactions are two: firstly, the alpha-quartz phase is quickly converted to the cristobalite phase under the action of a mineralizer, and the cristobalite has the excellent characteristics of high scattering property, good extinction effect, high whiteness, low density, bright color and the like, so that the whiteness is obviously improved. The second step is as follows: the anion in the mineralizer and the coloring iron ion in the quartz react chemically to generate white and water-insoluble iron salt, such as: the yellow in the quartz sand (powder) is whitened by the ferric sodium pyrophosphate, the sodium ferrophosphate and the like, and the whiteness of the quartz sand (powder) is greatly improved.
(2) The method has the advantages of simple process and low cost, and the quartz sand (powder) with high whiteness and few mottle points can be obtained after being processed by mature equipment on the existing market, so that the method can well meet the requirements of the market, particularly the plate industry, on the high-quality and high-whiteness quartz sand (powder). Compared with the existing pickling process, the method is green and environment-friendly, is suitable for large-scale production, and has wide market prospect.
The present invention will be described in further detail with reference to examples.
Detailed Description
The first embodiment is as follows:
the whitening process method of the quartz sand/powder comprises the following steps:
(1) stirring and mixing 1000 g of quartz sand raw material with blue light whiteness of 70 ℃ and particle composition of 26-120 meshes, 5 g of sodium silicate and 100 g of water uniformly in a stirrer, and then drying in a drying oven at the temperature of 150 ℃ to obtain a mixture;
(2) calcining the mixture in an electric furnace at the temperature of 1360 ℃, preserving heat for 30 minutes, and cooling to obtain a quartz sand calcined material, namely the whitened quartz sand;
(3) and removing impurity color particles from the whitened quartz sand through magnetic separation and/or color separation to obtain the high-whiteness quartz sand with the blue light whiteness value of 90 degrees.
Example two:
the whitening process method of the quartz sand/powder comprises the following steps:
(1) stirring and uniformly mixing 1000 g of quartz sand raw material with a blue light whiteness value of 70 ℃ and a particle size distribution of 26-120 meshes, 10 g of sodium pyrophosphate and 100 g of water in a stirrer, and then drying in a drying oven at the temperature of 150 ℃ to obtain a mixture;
(2) calcining the mixture in an electric furnace at 1380 ℃, preserving the heat for 60 minutes, and cooling to obtain a quartz sand calcined material, namely whitened quartz sand;
(3) and removing impurity color particles from the whitened quartz sand through magnetic separation and/or color separation to obtain the high-whiteness quartz sand with the blue light whiteness value of 95 degrees.
Example three:
the whitening process method of the quartz sand/powder comprises the following steps:
(1) stirring and mixing 1000 g of a quartz sand raw material with a blue light whiteness value of 65 ℃ and a particle size distribution of 30-150 meshes, 6 g of sodium tripolyphosphate and 100 g of water uniformly in a stirrer, and then drying in a drying oven at the temperature of 150 ℃ to obtain a mixture;
(2) calcining the mixture in an electric furnace at 1250 ℃, preserving heat for 45 minutes, and cooling to obtain a quartz sand calcined material, namely whitened quartz sand;
(3) and removing impurity color particles from the whitened quartz sand through magnetic separation and/or color separation to obtain the high-whiteness quartz sand with the blue light whiteness value of 93 degrees.
Example four:
the whitening process method of the quartz sand/powder comprises the following steps:
(1) stirring and uniformly mixing 1000 g of quartz sand raw material with blue light whiteness value of 68 ℃ and particle composition of 26-150 meshes, 2 g of sodium fluoride, 4 g of sodium silicate and 100 g of water in a stirrer, and then drying in a drying oven at the temperature of 150 ℃ to obtain a mixture;
(2) calcining the mixture in an electric furnace at the temperature of 1130 ℃, preserving the heat for 15 minutes, and cooling to obtain a quartz sand calcined material, namely the whitened quartz sand;
(3) and removing impurity color particles from the whitened quartz sand through magnetic separation and/or color separation to obtain the high-whiteness quartz sand with the blue light whiteness value of 85 degrees.
Example five:
the whitening process method of the quartz sand/powder comprises the following steps:
(1) stirring and uniformly mixing 1000 g of quartz sand raw material with a blue light whiteness value of 72 ℃ and a particle size distribution of 26-150 meshes, 1 g of lithium fluoride, 2 g of sodium hexametaphosphate and 100 g of water in a stirrer, and then drying in a drying oven at the temperature of 150 ℃ to obtain a mixture;
(2) calcining the mixture in an electric furnace at the temperature of 1280 ℃, preserving heat for 50 minutes, and cooling to obtain a quartz sand calcined material, namely the whitened quartz sand;
(3) and removing impurity color particles from the whitened quartz sand through magnetic separation and/or color separation to obtain the high-whiteness quartz sand with the blue light whiteness value of 88 degrees.
Example six:
the whitening process method of the quartz sand/powder comprises the following steps:
(1) stirring and uniformly mixing 1000 g of quartz sand raw material with blue light whiteness of 66 ℃ and particle composition of 26-150 meshes, 2 g of sodium carbonate, 3 g of sodium pyrophosphate and 100 g of water in a stirrer, and then drying in a drying oven at the temperature of 150 ℃ to obtain a mixture;
(2) calcining the mixture in an electric furnace at the temperature of 1300 ℃, preserving the heat for 50 minutes, and cooling to obtain a quartz sand calcined material, namely the whitened quartz sand;
(3) and removing impurity color particles from the whitened quartz sand through magnetic separation and/or color separation to obtain the high-whiteness quartz sand with the blue light whiteness value of 94 degrees.
Example seven:
the whitening process method of the quartz sand/powder comprises the following steps:
(1) stirring and mixing 1000 g of a quartz sand raw material with a blue light whiteness value of 76 degrees and a particle size distribution of 26-150 meshes, 3 g of potassium carbonate, 1 g of sodium fluoride and 100 g of water in a stirrer uniformly, and then drying in a drying oven at the temperature of 150 ℃ to obtain a mixture;
(2) calcining the mixture in an electric furnace at the temperature of 1220 ℃, preserving heat for 55 minutes, and cooling to obtain a quartz sand calcined material, namely the whitened quartz sand;
(3) and removing impurity color particles from the whitened quartz sand through magnetic separation and/or color separation to obtain the high-whiteness quartz sand with the blue light whiteness value of 90 degrees.
Example eight:
the whitening process method of the quartz sand/powder comprises the following steps:
(1) stirring and uniformly mixing 1000 g of quartz sand raw material with blue light whiteness of 68 ℃ and particle composition of 26-150 meshes, 3 g of sodium carbonate, 1 g of sodium fluoride and 100 g of water in a stirrer, and then drying in a drying oven at the temperature of 150 ℃ to obtain a mixture;
(2) calcining the mixture in an electric furnace at 1180 ℃, preserving heat for 35 minutes, and cooling to obtain a quartz sand calcined material, namely whitened quartz sand;
(3) and removing impurity color particles from the whitened quartz sand through magnetic separation and/or color separation to obtain the high-whiteness quartz sand with the blue light whiteness value of 85 degrees.
Example nine:
the whitening process method of the quartz sand/powder comprises the following steps:
(1) stirring and uniformly mixing 1000 g of quartz sand raw material with blue light whiteness of 63 degrees and particle composition of 26-150 meshes, 3 g of sodium carbonate and 100 g of water in a stirrer, and then drying in a drying oven at the temperature of 150 ℃ to obtain a mixture;
(2) calcining the mixture in an electric furnace at the temperature of 1280 ℃, preserving heat for 35 minutes, and cooling to obtain a quartz sand calcined material, namely the whitened quartz sand;
(3) and removing impurity color particles from the whitened quartz sand through magnetic separation and/or color separation to obtain the high-whiteness quartz sand with the blue light whiteness value of 89 degrees.
Example ten:
the whitening process method of the quartz sand/powder comprises the following steps:
(1) stirring and uniformly mixing 1000 g of a quartz powder raw material with a blue light whiteness value of 70 degrees, a granularity of +325 meshes and a screen residue of less than 2 percent with 3 g of sodium carbonate, 1 g of sodium phosphate and 100 g of water in a stirrer, and then drying in a drying oven at the temperature of 150 ℃ to obtain a mixture;
(2) and (3) calcining the mixture in an electric furnace at the temperature of 1280 ℃, preserving the heat for 120 minutes, and cooling to obtain a quartz powder calcined material, namely the whitened quartz powder, wherein the blue light whiteness value of the quartz powder is 92 ℃.
Example eleven:
the difference between the present embodiment and the first embodiment is:
and (3) milling the high-whiteness quartz sand obtained in the step (3) in the embodiment by using milling equipment to obtain the high-whiteness quartz powder with the fineness of more than or equal to 325 meshes and the blue light whiteness value of 90 degrees.
The method for testing the blue light whiteness value comprises the following steps: and filling quartz sand/powder in a material box, paving, and measuring by using a blue light whiteness instrument to obtain a blue light whiteness value.
Claims (8)
1. A whitening process method of quartz sand/powder is characterized by comprising the following steps:
(1) uniformly stirring and mixing a quartz sand raw material with the particle size composition of 26-150 meshes or a quartz powder raw material with the fineness of more than or equal to 325 meshes and a mineralizer to form a mixture; wherein the amount of the mineralizer is 0.1-2.0 wt% of the quartz sand raw material or the quartz powder raw material;
(2) and calcining the mixture at 1050-1550 ℃, preserving heat for 10-180 minutes, and cooling to obtain a quartz sand calcined material or a quartz powder calcined material, namely the whitened quartz sand or whitened quartz powder.
2. The quartz sand/powder whitening process method according to claim 1, characterized in that: and removing impurity color particles from the whitened quartz sand through magnetic separation and/or color separation to obtain the high-whiteness quartz sand.
3. The quartz sand/powder whitening process method according to claim 1, characterized in that: and grinding the whitened quartz sand by using a grinding device to obtain whitened quartz sand with the fineness of more than or equal to 325 meshes.
4. The quartz sand/powder whitening process method according to claim 2, characterized in that: and the high-whiteness quartz sand is ground by a grinding device to obtain high-whiteness quartz powder with the fineness of more than or equal to 325 meshes.
5. The quartz sand/powder whitening process method according to claim 1, characterized in that: the mineralizer is one or the combination of calcium fluoride, sodium silicate, sodium fluoride, sodium carbonate, potassium fluoride, potassium carbonate, lithium fluoride, lithium carbonate, sodium acetate, lithium acetate, sodium pyrophosphate, trisodium phosphate, sodium tripolyphosphate, sodium hexametaphosphate and lithium phosphate.
6. The quartz sand/powder whitening process method according to claim 1, characterized in that: the blue light whiteness value of the quartz sand raw material or the quartz powder raw material is 60-76 degrees.
7. The quartz sand/powder whitening process method according to claim 2, characterized in that: the blue light whiteness value of the high-whiteness quartz sand is 80-100 degrees.
8. The quartz sand/powder whitening process method according to claim 1, characterized in that: the stirring and mixing mode in the step (1) is dry mixing or wet mixing; the wet mixing mode is that water, quartz sand raw material or quartz powder raw material and mineralizer are added additionally to be stirred and mixed, and then the mixture is formed after drying.
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| CN202110382225.8A CN112938996A (en) | 2021-04-09 | 2021-04-09 | Whitening process method of quartz sand/powder |
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| CN202110382225.8A CN112938996A (en) | 2021-04-09 | 2021-04-09 | Whitening process method of quartz sand/powder |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117567023A (en) * | 2024-01-16 | 2024-02-20 | 青州统一重工机械有限公司 | Production process for processing ultra-white sand by quartz sand |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107824330A (en) * | 2017-09-15 | 2018-03-23 | 江苏闽江矿业有限公司 | A kind of production method of artificial stone quartz sand |
| CN109052417A (en) * | 2018-09-11 | 2018-12-21 | 安徽科技学院 | A kind of synthetic method of high-purity low-temperature phase cristobalite |
| CN109665530A (en) * | 2019-01-23 | 2019-04-23 | 景德镇陶瓷大学 | A method of ultra-fine cristobalite powder is prepared with quartz sand |
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2021
- 2021-04-09 CN CN202110382225.8A patent/CN112938996A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107824330A (en) * | 2017-09-15 | 2018-03-23 | 江苏闽江矿业有限公司 | A kind of production method of artificial stone quartz sand |
| CN109052417A (en) * | 2018-09-11 | 2018-12-21 | 安徽科技学院 | A kind of synthetic method of high-purity low-temperature phase cristobalite |
| CN109665530A (en) * | 2019-01-23 | 2019-04-23 | 景德镇陶瓷大学 | A method of ultra-fine cristobalite powder is prepared with quartz sand |
Non-Patent Citations (1)
| Title |
|---|
| CHEN NANCHUN ET AL.: "XRD and Morphologic Analysis of α-Cristobalite Produced from Silica mine Waste Under Lower Calcination Temperature", 《MATERIALS SCIENCE FORUM》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117567023A (en) * | 2024-01-16 | 2024-02-20 | 青州统一重工机械有限公司 | Production process for processing ultra-white sand by quartz sand |
| CN117567023B (en) * | 2024-01-16 | 2024-04-12 | 青州统一重工机械有限公司 | Production process for processing ultra-white sand by quartz sand |
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Application publication date: 20210611 |