CN-122010150-A - Method for preparing high-purity magnesium oxide product by carbonization and purification of light-burned powder and product

Abstract

The invention discloses a method for preparing a high-purity magnesium oxide product by carbonizing and purifying light-burned powder. The method comprises the steps of putting first light burned powder and process water into a first reaction device, introducing process gas into the first reaction device, and reacting to obtain heavy magnesium water. And (3) carrying out pretreatment on the heavy magnesium water to obtain purified heavy magnesium water. And (3) introducing purified heavy magnesium water into a second reaction device to obtain the slurry containing magnesium carbonate. The slurry is subjected to a post-treatment to obtain a first pre-product comprising high purity magnesium carbonate. The first pre-product and the second light burned powder are mixed and then pressed to form a furnace burden, or the first pre-product is calcined to obtain a second pre-product containing high-purity magnesium oxide, and the second pre-product and the second light burned powder are mixed and then pressed to form the furnace burden. Smelting or sintering furnace burden to prepare high-purity magnesia products such as high-purity fused magnesia or high-purity sintered magnesia respectively.

Inventors

• WANG DEXI
• XU HUI
• WANG MENG
• ZHAO HANG
• CUI WEILIN
• WANG XIAO
• WANG JUN
• WANG SIYAO

Assignees

• 辽宁博仕佶镁新材料科技有限公司

Dates

Publication Date

20260512

Application Date

20260131

Claims (11)

1. 1. The method for preparing the high-purity magnesium oxide product by carbonizing and purifying the light burned powder is characterized by comprising the following steps of: s1, putting first light burned powder and process water into a first reaction device, and introducing process gas into the first reaction device to obtain heavy magnesium water through carbonization reaction, wherein the process gas contains carbon dioxide; s2, pre-treating the heavy magnesium water, and removing impurities in the heavy magnesium water to obtain purified heavy magnesium water; S3, introducing purified heavy magnesium water into a second reaction device, and obtaining slurry containing magnesium carbonate through pyrolysis reaction; s4, carrying out post-treatment on the slurry to obtain a first pre-product, wherein the first pre-product comprises high-purity magnesium carbonate; S5, mixing the first pre-product with second light-burned powder and then compacting to obtain a furnace burden, or calcining the first pre-product to obtain a second pre-product, mixing the second pre-product with the second light-burned powder and then compacting to obtain the furnace burden, wherein the second pre-product comprises high-purity magnesium oxide; s6, charging the furnace burden into an electric melting furnace for smelting to prepare a high-purity magnesia product, wherein the high-purity magnesia product is high-purity fused magnesia, or charging the furnace burden into a sintering furnace for sintering to prepare the high-purity magnesia product, and the high-purity magnesia product is high-purity sintered magnesia.
2. 2. The method for producing a high purity magnesia product by carbonization and purification of light burned powder according to claim 1, wherein the process gas comprises at least one of flue gas generated during calcination, pyrolysis, electric smelting or sintering of carbonate minerals and combustion exhaust gas generated during combustion of fuel.
3. 3. The method for preparing a high-purity magnesia product by carbonizing and purifying light burned powder according to claim 1, wherein the process gas comprises at least one of calcining flue gas generated in the process of preparing the first light burned powder and/or the second light burned powder, flue gas generated in the pyrolysis reaction process of S3, flue gas generated in the process of calcining the first pre-product in S5, and flue gas generated in the process of smelting or sintering furnace burden in S6.
4. 4. The method for preparing a high purity magnesia product by carbonization and purification of light burned powder according to claim 1, wherein the post-treatment in S4 comprises at least one of filtration and drying.
5. 5. The method for preparing a high-purity magnesia product by carbonizing and purifying light-burned powder according to claim 1, wherein the magnesia content of the second light-burned powder is not less than 95%, and the magnesia content of the first light-burned powder is lower than that of the second light-burned powder.
6. 6. The method for preparing a high-purity magnesia product by carbonizing and purifying light burned powder according to claim 1, wherein the first light burned powder is prepared from at least one of low grade magnesite and tailing powder.
7. 7. The method for preparing a high purity magnesia product by carbonization purification of light burned powder according to claim 1, wherein when the first pre-product and the second light burned powder are mixed, the mass ratio between the first pre-product and the second light burned powder is in the range of (7-10): 1.
8. 8. The method for preparing a high purity magnesia product by carbonization and purification of light burned powder according to claim 1, wherein when the second pre-product and the second light burned powder are mixed, the mass ratio between the second pre-product and the second light burned powder is in the range of (3.5-5): 1.
9. 9. The method for preparing a high-purity magnesium oxide product by carbonizing and purifying light-burned powder according to claim 1, wherein the pressure of the carbonization reaction is 0.05-0.8 MPa, the reaction temperature of the carbonization reaction is 10-60 ℃, and the carbonization residence time is 15-180 min.
10. 10. A high purity magnesia product, characterized in that it is obtained by the method of preparing a high purity magnesia product by carbonization and purification of light burned powder according to any one of claims 1-9.
11. 11. The high purity magnesia product of claim 10, wherein the magnesia content of the high purity magnesia product is above 98.2%.

Description

Method for preparing high-purity magnesium oxide product by carbonization and purification of light-burned powder and product Technical Field The invention belongs to the technical field of inorganic material preparation, and particularly relates to a method for preparing a high-purity magnesium oxide product by carbonizing and purifying light-burned powder and the high-purity magnesium oxide product prepared by the method. Background Magnesia products such as sintered magnesia, electric smelting magnesia and the like are important refractory material raw materials, are obtained by respectively putting raw materials such as magnesite or light burned powder and the like into a sintering furnace for sintering or an electric melting furnace for smelting, and the purity is an important factor for determining the refractory performance, erosion resistance and high-temperature structural strength of the product. The high-purity magnesia products such as high-purity sintered magnesia with magnesia content higher than 98 percent, high-purity fused magnesia and the like belong to high-end products, have higher added value of products, are widely applied to the high-temperature industrial fields such as steel, cement, glass, ceramics and the like, and are important basic raw materials of refractory materials and magnesia chemical products. At present, the production of high-purity sintered magnesia and high-purity fused magnesia mainly depends on high-quality magnesite as a raw material. The magnesium ore reserves such as magnesite in China are in the front of the world, however, along with the large-scale exploitation and utilization of the magnesite for years, the resources of high-grade magnesite (the magnesium oxide content is more than or equal to 46%) in China are increasingly exhausted, the high-quality magnesite reserves are drastically reduced, the production cost of high-purity sintered magnesite and high-purity fused magnesium is continuously increased, the development of related industries is severely restricted, and the production of high-purity magnesium oxide products with increasingly urgent demands is in dilemma. On the other hand, during the exploitation and processing of magnesite, a large amount of low-grade magnesite (magnesium oxide content is 30% -45%) and tailing powder are generated. The low-grade magnesium resources are difficult to effectively utilize due to high impurity content and high purification difficulty, are usually piled up or buried as waste, not only cause serious resource waste, but also cause serious environmental problems due to low comprehensive utilization rate of resources. In recent years, the stock of magnesite tailings in China reaches hundreds of millions of tons, and the new tailings amount exceeds tens of millions of tons each year. The long-term stacking of the tailings not only occupies a large amount of land resources, but also causes serious pollution to surrounding soil, water and atmospheric environment due to dust, heavy metal and other pollutants, and has huge environmental potential safety hazards. In addition, a large amount of carbon dioxide gas is discharged in the process of calcining magnesite, producing light burned powder and the like. The emission of these carbon dioxide not only causes the greenhouse effect, but also wastes valuable carbon resources. How to recycle the carbon dioxide generated in the production process as a resource, thereby realizing the aim of changing waste into valuable, and becoming the urgent requirement for green development in the magnesite industry. At present, the production of high-purity sintered magnesia and high-purity fused magnesia mainly adopts the traditional purification processes such as a flotation method, a gravity separation method, a chemical precipitation method and the like, and the content of magnesia in raw materials is further improved on the basis of high-grade ore. Although the method can improve the purity of the magnesium oxide product to a certain extent, the method has larger limitation, and mainly solves the problems of complex process flow, large equipment investment and high energy consumption, the requirement of using a large amount of chemical agents to generate secondary pollution, the limited purification effect, poor adaptability to low-grade mineral raw materials, and incapability of effectively utilizing valuable components in tailings, so that the low-grade mineral raw materials cannot be used for industrial cognition of high-purity sintered magnesia and high-purity fused magnesium production. Disclosure of Invention Aiming at the problems, the invention provides a method for preparing high-purity magnesia products such as high-purity sintered magnesia and high-purity fused magnesia by carbonizing and purifying light-burned powder, which takes low-grade light-burned powder from low-grade magnesium resources as a main raw material and carbon dioxide discharged in the mineral processing pr