CN112676029A - Method for preparing water glass by using purified iron tailings - Google Patents
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Abstract
本发明的目的是针对铁尾矿大量排放造成严重的资源浪费和环境污染问题，提供了一种利用提纯的铁尾矿制备水玻璃的方法，属于水玻璃技术领域。本发明的技术方案为，首先，将铁尾矿分选出富硅原料，然后，将富硅原料酸浸，除去富硅原料中的酸溶性杂质，然后水洗、烘干，获得石英砂原料，最后，将石英砂原料与碱溶液加入反应釜中反应，反应结束后，冷却、过滤，过滤后的液体进行浓缩即获得水玻璃产品。该方法分选出铁尾矿中的有价组分SiO2，再与碱溶液反应，制备模数为2.5‑3.5的液体水玻璃。本发明通过利用提纯的铁尾矿制备高附加值产品水玻璃，实现了铁尾矿的无害化处置和资源化利用，其经济社会效益显著。
The purpose of the present invention is to provide a method for preparing water glass using purified iron tailings, which belongs to the technical field of water glass, aiming at the serious resource waste and environmental pollution caused by the massive discharge of iron tailings. The technical scheme of the present invention is as follows: firstly, the iron tailings are sorted into silicon-rich raw materials, then, the silicon-rich raw materials are acid leached to remove acid-soluble impurities in the silicon-rich raw materials, and then washed with water and dried to obtain quartz sand raw materials, Finally, the raw materials of quartz sand and alkali solution are added to the reaction kettle for reaction. After the reaction is completed, cooling and filtration are performed, and the filtered liquid is concentrated to obtain the water glass product. The method separates the valuable component SiO 2 in the iron tailings, and then reacts with an alkali solution to prepare liquid water glass with a modulus of 2.5-3.5. The invention realizes the harmless disposal and resource utilization of the iron tailings by using the purified iron tailings to prepare the high value-added product water glass, and has significant economic and social benefits.
Description
Technical Field
The invention belongs to the technical field of water glass, and particularly relates to a method for preparing water glass by using purified iron tailings.
Background
The iron tailings are waste residues discharged after iron ore concentrate is selected by a concentrating mill, and are one of main industrial solid wastes. With the rapid development of the steel industry, the mining amount of iron ore is continuously increased, and the proportion of iron tailings in industrial solid waste is increased. The tailings have small granularity, light weight and large surface area, and are easy to flow and collapse and leak when stacked, and the tailings dust flies upward around under the push of wind power, so that not only is the waste of mineral resources caused, but also a large amount of land is occupied, and serious environmental pollution is caused. Therefore, the research on the comprehensive utilization of the iron tailings is urgent.
The main chemical composition of the iron tailings is SiO2About 60%, and then Fe, Al, Ca, Mg, etc. Silica is a raw material for producing water glass. At present, the comprehensive utilization rate of tailings in China is only 7%, the main utilization direction is the field of buildings, and reports on the aspect of developing water glass by using iron tailings are almost absent.
Water glass is a soluble inorganic silicate with the chemical formula R2O·nSiO2N is the modulus of the water glass, and is generally between 1.5 and 4.0, and the modulus of the water glass produced in China is generally between 2.4 and 3.3. The sodium silicate with different modulus has different purposes, and is widely applied to the fields of casting, papermaking, ceramics, clay, mine beneficiation reagents, kaolin, washing and the like.
Therefore, the preparation of the high value-added product water glass by using the iron tailings has important practical significance for reducing the discharge of the iron tailings, improving the comprehensive utilization degree of the iron tailings and reducing the environmental pollution.
Disclosure of Invention
The invention aims to solve the problems of serious resource waste and environmental pollution caused by the large discharge of iron tailings and provides utilizationA method for preparing water glass by using purified iron tailings. The method is used for separating the valuable component SiO in the iron tailings2And then reacting with alkali solution to prepare the liquid water glass with the modulus of 2.5-3.5. The invention realizes harmless disposal and resource utilization of the iron tailings by preparing the high value-added product water glass by using the purified iron tailings, and has remarkable economic and social benefits.
The technical scheme of the invention is that the method for preparing the water glass by using the purified iron tailings comprises the following steps:
1) silicon-rich raw material separated from iron tailings
a. Classifying a swirler: carrying out cyclone classification treatment on the iron tailings to obtain settled sand and overflow products;
b. roughing a spiral chute: b, roughly selecting the settled sand product obtained in the step a by using a spiral chute to obtain an iron intergrowth and roughly selected tailings;
c. sweeping of a spiral chute: b, performing spiral chute scavenging on the rougher tailings in the step b to obtain iron intergrowths and scavenged tailings;
d. performing low-intensity magnetic separation: b, carrying out low-intensity magnetic separation on the overflow product subjected to classification by the cyclone in the step a to obtain an iron intergrowth and low-intensity magnetic tailings;
e. strong magnetic separation: d, carrying out strong magnetic separation on the weak magnetic tailings in the step d to obtain iron intergrowth and strong magnetic tailings;
f. combining the scavenged tailings in the step c and the strong magnetic tailings in the step e into a final silicon-rich raw material;
2) acid leaching the silicon-rich raw material, removing acid-soluble impurities such as Ca, Mg, Al, Fe and the like in the silicon-rich raw material, then washing with water and drying to obtain a quartz sand raw material;
3) preparation of water glass
Mixing a quartz sand raw material and an alkali solution according to a mass ratio of 1: 5-1: 8, adding the mixture into a reaction kettle, reacting at the temperature of 170-.
In the method for preparing the water glass, in the step 1), the iron mass percent of the iron tailings is less than or equal to 18 percent, and SiO is used2The mass percentage content is more than or equal to 50 percent;
in the above method for preparing water glass, in the steps b and c of step 1), the spiral chute is a spiral chute with phi 1.2m to phi 1.5 m;
in the method for preparing the water glass, in the step 1) d, the field intensity of the low-intensity magnetic separation is 120-150 mT;
in the method for preparing the water glass, in the step 1), the field intensity of the strong magnetic separation is 600-1000 mT;
in the method for preparing the water glass, in the step 2), the mass concentration of the acid is 10-15%;
further, the acid is industrial waste acid, or the acid is hydrochloric acid, sulfuric acid, nitric acid or a mixture of 2 or 3 of the hydrochloric acid, the sulfuric acid and the nitric acid;
in the above method for preparing water glass, in the step 2), the washing liquid obtained after washing is fed into a recovery processing system;
in the above method for preparing water glass, in the step 2), SiO in the quartz sand2The mass percentage content is 88-97%;
in the above method for preparing water glass, in the step 3), the alkali solution is a sodium hydroxide solution with a mass fraction of 20% -40%.
Compared with the prior art, the invention has the advantages that:
1. the modulus of the liquid water glass prepared by the invention can reach 2.5-3.5, the process is simple, the operation is easy, the cost is low, and the raw material source is wide.
2. The invention adopts SiO of silicon-rich raw material after reselection and magnetic separation treatment2The mass percentage content can reach 80-86%, and the quartz sand raw material SiO obtained after the industrial waste acid is subjected to impurity removal2The mass percentage content of the silicon-rich raw material can reach 88-97 percent, and SiO in the silicon-rich raw material is improved after the industrial waste acid is subjected to acid pickling treatment2The mass percentage content of the waste acid is high, and the secondary utilization of the industrial waste acid is realized.
The invention adopts the iron tailings to prepare the high value-added product water glass, realizes the harmless treatment and resource utilization of the iron tailings, provides a new way for the full utilization of valuable components in the iron tailings, and effectively avoids the environmental pollution caused by the large discharge of the iron tailings.
Drawings
FIG. 1 is a flow chart of the method of the present invention.
Detailed Description
The following further illustrates embodiments of the invention in connection with specific examples.
1. The iron tailings used in the test are iron tailings of a certain plant, and the chemical composition of the iron tailings is shown in table 1.
TABLE 1 chemical composition of iron tailings of a certain selection plant
2. The waste acid solution used in the test is obtained from waste acid from a certain steel plant.
Example 1
And (4) carrying out cyclone classification treatment on the iron tailings to obtain settled sand and overflow products. Feeding the settled sand product into a spiral chute with the diameter of phi 1.5m for roughing, and feeding roughed tailings into a spiral chute with the diameter of phi 1.5m for scavenging; feeding the overflow product into a cylindrical magnetic separator with the field intensity of 150mT for low-intensity magnetic separation, and feeding the low-intensity magnetic tailings into the cylindrical magnetic separator with the field intensity of 1000mT for high-intensity magnetic separation; the scavenged tailings and the strong magnetic tailings are combined into a silicon-rich raw material, and SiO in the silicon-rich raw material2The mass percentage of (B) is 86.68%. Acid washing the silicon-rich raw material to remove acid-soluble impurities such as Ca, Mg, Al and Fe in the silicon-rich raw material, washing with water (the washing solution is fed into a recovery processing system), and drying to obtain the raw material quartz sand raw material for preparing the water glass, wherein SiO in the quartz sand is2The content was 95.88%.
Mixing quartz sand raw material and 30% sodium hydroxide solution according to the proportion of 1: 8, adding into a reaction kettle, reacting at 200 ℃ for 3.5h, cooling and filtering after the reaction is finished, concentrating the filtered liquid to obtain liquid water glass, and adding Na in the obtained liquid water glass2The mass percentage of O is 13.68 percent, and SiO is233.65 percent by mass and the modulus of the water glass is 2.54.
Example 2
And (4) carrying out cyclone classification treatment on the iron tailings to obtain settled sand and overflow products. Feeding the settled sand product into a phi 1.2m spiral chute for roughing, and feeding roughed tailings into a phi 1.2m spiral chute for scavenging; feeding the overflow product into a cylindrical magnetic separator with the field intensity of 140mT for low-intensity magnetic separation, and feeding the low-intensity magnetic tailings into a cylindrical magnetic separator with the field intensity of 800mT for high-intensity magnetic separation; the scavenged tailings and the strong magnetic tailings are combined into a silicon-rich raw material, and SiO in the silicon-rich raw material2The mass percentage of (B) is 83.47%. Acid washing the silicon-rich raw material to remove acid-soluble impurities such as Ca, Mg, Al and Fe in the silicon-rich raw material, wherein the mass concentration of the acid is 15%, then washing with water (the washing solution is fed into a recovery processing system), and drying to obtain the raw material quartz sand raw material for preparing the water glass, wherein SiO in the quartz sand is used as the raw material2The mass percentage content is 91.12 percent.
Mixing quartz sand raw material and 25% sodium hydroxide solution according to the proportion of 1: 6, adding the mixture into a reaction kettle, reacting at 190 ℃ for 2h, cooling and filtering after the reaction is finished, concentrating the filtered liquid to obtain liquid water glass, and adding Na in the obtained liquid water glass2The mass percentage of O is 10.68 percent, and SiO is2The mass percentage content is 30.01 percent, and the modulus of the water glass is 2.90 percent.
Example 3
And (4) carrying out cyclone classification treatment on the iron tailings to obtain settled sand and overflow products. Feeding the settled sand product into a spiral chute with the diameter of phi 1.5m for roughing, and feeding roughed tailings into a spiral chute with the diameter of phi 1.5m for scavenging; feeding the overflow product into a cylindrical magnetic separator with the field intensity of 140mT for low-intensity magnetic separation, and feeding the low-intensity magnetic tailings into a cylindrical magnetic separator with the field intensity of 850mT for high-intensity magnetic separation; the scavenged tailings and the strong magnetic tailings are combined into a silicon-rich raw material, and SiO in the silicon-rich raw material2The mass percentage of (B) is 84.52%. Acid-washing the silicon-rich raw material to 10% acid mass concentration, removing acid-soluble impurities such as Ca, Mg, Al and Fe in the silicon-rich raw material, then washing with water (the washing solution is fed into a recovery processing system), and drying to obtain the raw material quartz sand raw material for preparing the water glass, wherein SiO in the quartz sand is used as the raw material2The mass percentage content is 94.21 percent.
Mixing quartz sand raw material and 30% sodium hydroxide solution according to the proportion of 1: 7, adding into a reaction kettle, reacting at 200 ℃ for 3h, cooling and filtering after the reaction is finished, concentrating the filtered liquid to obtain liquid water glass, wherein Na in the liquid water glass is obtained at the moment2The mass percentage of O is 10.05 percent, and SiO is2The mass percentage content is 31.36 percent, and the modulus of the water glass is 3.22.
Example 4
And (4) carrying out cyclone classification treatment on the iron tailings to obtain settled sand and overflow products. Feeding the settled sand product into a phi 1.2m spiral chute for roughing, and feeding roughed tailings into a phi 1.2m spiral chute for scavenging; feeding the overflow product into a cylindrical magnetic separator with the field intensity of 120mT for low-intensity magnetic separation, and feeding the low-intensity magnetic tailings into a cylindrical magnetic separator with the field intensity of 600mT for high-intensity magnetic separation; the scavenged tailings and the strong magnetic tailings are combined into a silicon-rich raw material, and SiO in the silicon-rich raw material2The mass percentage of (B) is 80.06%. Acid washing the silicon-rich raw material to remove acid-soluble impurities such as Ca, Mg, Al and Fe in the silicon-rich raw material with the acid mass concentration of 15%, then washing with water (the washing solution is fed into a recovery processing system), and drying to obtain the raw material quartz sand raw material for preparing the water glass, wherein SiO is used as the raw material2The mass percentage content is 91.45 percent.
Mixing quartz sand raw material and sodium hydroxide solution with mass concentration of 20% according to a ratio of 1: 5, adding into a reaction kettle, reacting at 180 ℃ for 2.5h, cooling and filtering after the reaction is finished, concentrating the filtered liquid to obtain liquid water glass, wherein Na in the liquid water glass is obtained at the moment2The mass percentage of O is 8.86 percent, and SiO is2The mass percentage content is 29.95 percent, and the modulus of the water glass is 3.49.
Example 5
And (4) carrying out cyclone classification treatment on the iron tailings to obtain settled sand and overflow products. Feeding the settled sand product into a spiral chute with the diameter of phi 1.3m for roughing, and feeding roughed tailings into a spiral chute with the diameter of phi 1.3m for scavenging; feeding the overflow product into a cylindrical magnetic separator with the field intensity of 130mT for low-intensity magnetic separation, and feeding the low-intensity magnetic tailings into a cylindrical magnetic separator with the field intensity of 850mT for high-intensity magnetic separation; combining the scavenging tailings and the strong magnetic tailings into rich tailingsSilicon feedstock, in this case SiO in the silicon-rich feedstock2The mass percentage of (B) is 83.75%. Acid washing the silicon-rich raw material to acid mass concentration of 12.5%, removing acid-soluble impurities such as Ca, Mg, Al and Fe in the silicon-rich raw material, then washing with water (washing solution is fed into a recovery processing system), and drying to obtain the raw material quartz sand raw material for preparing the water glass, wherein SiO is used as the raw material2The mass percentage content is 89.68 percent.
Mixing quartz sand raw material and sodium hydroxide solution with mass concentration of 40% according to a ratio of 1: 7, adding into a reaction kettle, reacting at 170 ℃ for 4h, cooling and filtering after the reaction is finished, concentrating the filtered liquid to obtain liquid water glass, wherein Na in the liquid water glass is obtained at the moment2The mass percentage of O is 10.68 percent, and SiO is2The mass percentage content is 28.89%, and the water glass modulus is 2.79.
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Cited By (2)
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| CN113526514A (en) * | 2021-07-02 | 2021-10-22 | 鞍钢集团矿业有限公司 | A kind of method that utilizes iron tailings to prepare silicon micropowder |
| CN113772686A (en) * | 2021-10-22 | 2021-12-10 | 北京润捷浩达科技有限公司 | Method for preparing water glass and co-producing metal salt crystals by using silicon-rich clay |
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| CN113772686B (en) * | 2021-10-22 | 2022-04-12 | 潘爱芳 | Method for preparing water glass and co-producing metal salt crystals by using silicon-rich clay |
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Application publication date: 20210420 |