A kind of manufacturing method of electrical grade magnesium oxide powder additive

Abstract

The invention provides a manufacturing method of electrician level magnesia powder additive, which includes steps of S1, fusing serpentine and separating it after cooling to obtain magnesium silicate coarse material and ferrosilicon; S2, grinding and grading the magnesium silicate coarse material; S3, performing alkali-washing on the magnesium silicate; S4, water-washing and drying magnesium-enriched silicate; S5, smashing, sieving and magnetic-selecting the magnesium-enriched silicate; S6, mixing the magnesium-enriched silicate with kaoline, and preparing the electrician level magnesia powder additive. By using serpentine and kaoline as raw materials, the electrician level magnesia powder additive is prepared; the additive is wide in raw material source and low in cost; moreover, after adding the electrician level magnesia powder additive to the electrician level magnesium oxide, electrical properties of electrician level magnesium oxide are improved; meanwhile, requirements on MgO content in electrically fused magnesite is reduced, thereby enlarging the applicable scale of the electrically fused magnesite raw material and improving the utilization rate of the low-grade the electrically fused magnesite; the manufacturing method is good for solving the development and utilization of low-grade magnesia.

Description

technical field

[0001] The invention relates to a method for manufacturing an electrical grade magnesium oxide powder additive. Background technique

[0002] In recent years, with the increase of magnesium ore mining, the cost of magnesium ore mining has increased, which has not only reduced the mining volume of high-grade magnesium ore year by year, but also increased its mining cost year by year. In order to respond to the national energy conservation and environmental protection policy, The development and utilization of low-grade magnesium ore has become a top priority.

[0003] Magnesia mined from magnesia can be used to produce electrical grade magnesia after processing. Among them, electrical grade magnesia is mainly used to make electric heating elements with high operating temperature and can withstand high temperature environment, but processing from low-grade magnesia The produced low-grade fused magnesia with a magnesium oxide content of 94-95% can only be used ...

Examples

Embodiment 1

[0126] 1. Mix graphite and magnesium powder at a mass ratio of 1:10 to prepare a reducing agent. In terms of parts by weight, 100 parts of serpentine and 0.8 parts of reducing agent were mixed respectively, and after mixing, they were placed in a steelmaking ladle, heated by a three-phase electric arc, and the mixture was melted at 2150 ° C, kept for 4 hours, and passed through Separation and crushing are carried out after natural cooling to obtain magnesium silicate coarse material and ferrosilicon alloy.

[0127] 2. Grinding the coarse magnesium silicate material through a dry mill to obtain magnesium silicate powder, which is then classified.

[0128] 3. Mix the graded magnesium silicate powder with 6mol / L sodium hydroxide solution at a mass volume ratio of 1.2g / mL, and carry out alkali washing, wherein the alkali washing temperature is 20°C, and the alkali washing temperature of 0.1MPa After carrying out alkali washing treatment under pressure for 100 minutes, the alkali ...

Embodiment 2

[0134] 1. Mix graphite and magnesium powder at a mass ratio of 1:8 to prepare a reducing agent. In terms of parts by weight, 100 parts of serpentine and 1.2 parts of reducing agent were mixed respectively, and after mixing, they were placed in a steelmaking ladle, heated by a three-phase electric arc, and the mixture was melted at 2000°C, kept for 3 hours, and then Separation and crushing are carried out after natural cooling to obtain magnesium silicate coarse material and ferrosilicon alloy.

[0135] 2. Grinding the coarse magnesium silicate material through a dry mill to obtain magnesium silicate powder, which is then classified.

[0136] 3. Mix the graded magnesium silicate powder with 9mol / L sodium hydroxide solution at a mass volume ratio of 1.0g / mL, and carry out alkali washing, wherein the alkali washing temperature is 10°C, and the alkali washing temperature of 0.25MPa After carrying out alkali washing treatment under pressure for 50 minutes, the alkali washing ends....

Embodiment 3

[0142] 1. Mix graphite and magnesium powder at a mass ratio of 1:5 to prepare a reducing agent. In terms of parts by weight, 100 parts of serpentine and 1.0 part of reducing agent were mixed respectively, and after mixing, they were placed in a steelmaking ladle, heated by a three-phase electric arc, and the mixture was melted at 1950°C, kept for 5 hours, and passed through Separation and crushing are carried out after natural cooling to obtain magnesium silicate coarse material and ferrosilicon alloy.

[0143] 2. Grinding the coarse magnesium silicate material through a dry mill to obtain magnesium silicate powder, which is then classified.

[0144] 3. Mix the graded magnesium silicate powder with 10mol / L sodium hydroxide solution at a mass volume ratio of 0.9g / mL, and carry out alkali cleaning. After alkali washing treatment under pressure for 80 minutes, the alkali washing ends.

[0145] 4. Filter the alkali washing solution to obtain magnesium-rich silicate precipitates,...

technical field

[0001] The invention relates to a method for manufacturing an electrical grade magnesium oxide powder additive. Background technique

[0002] In recent years, with the increase of magnesium ore mining, the cost of magnesium ore mining has increased, which has not only reduced the mining volume of high-grade magnesium ore year by year, but also increased its mining cost year by year. In order to respond to the national energy conservation and environmental protection policy, The development and utilization of low-grade magnesium ore has become a top priority.

[0003] Magnesia mined from magnesia can be used to produce electrical grade magnesia after processing. Among them, electrical grade magnesia is mainly used to make electric heating elements with high operating temperature and can withstand high temperature environment, but processing from low-grade magnesia The produced low-grade fused magnesia with a magnesium oxide content of 94-95% can only be used ...

Examples

Embodiment 1

[0126] 1. Mix graphite and magnesium powder at a mass ratio of 1:10 to prepare a reducing agent. In terms of parts by weight, 100 parts of serpentine and 0.8 parts of reducing agent were mixed respectively, and after mixing, they were placed in a steelmaking ladle, heated by a three-phase electric arc, and the mixture was melted at 2150 ° C, kept for 4 hours, and passed through Separation and crushing are carried out after natural cooling to obtain magnesium silicate coarse material and ferrosilicon alloy.

[0127] 2. Grinding the coarse magnesium silicate material through a dry mill to obtain magnesium silicate powder, which is then classified.

[0128] 3. Mix the graded magnesium silicate powder with 6mol / L sodium hydroxide solution at a mass volume ratio of 1.2g / mL, and carry out alkali washing, wherein the alkali washing temperature is 20°C, and the alkali washing temperature of 0.1MPa After carrying out alkali washing treatment under pressure for 100 minutes, the alkali ...

Embodiment 2

[0134] 1. Mix graphite and magnesium powder at a mass ratio of 1:8 to prepare a reducing agent. In terms of parts by weight, 100 parts of serpentine and 1.2 parts of reducing agent were mixed respectively, and after mixing, they were placed in a steelmaking ladle, heated by a three-phase electric arc, and the mixture was melted at 2000°C, kept for 3 hours, and then Separation and crushing are carried out after natural cooling to obtain magnesium silicate coarse material and ferrosilicon alloy.

[0135] 2. Grinding the coarse magnesium silicate material through a dry mill to obtain magnesium silicate powder, which is then classified.

[0136] 3. Mix the graded magnesium silicate powder with 9mol / L sodium hydroxide solution at a mass volume ratio of 1.0g / mL, and carry out alkali washing, wherein the alkali washing temperature is 10°C, and the alkali washing temperature of 0.25MPa After carrying out alkali washing treatment under pressure for 50 minutes, the alkali washing ends....

Embodiment 3

[0142] 1. Mix graphite and magnesium powder at a mass ratio of 1:5 to prepare a reducing agent. In terms of parts by weight, 100 parts of serpentine and 1.0 part of reducing agent were mixed respectively, and after mixing, they were placed in a steelmaking ladle, heated by a three-phase electric arc, and the mixture was melted at 1950°C, kept for 5 hours, and passed through Separation and crushing are carried out after natural cooling to obtain magnesium silicate coarse material and ferrosilicon alloy.

[0143] 2. Grinding the coarse magnesium silicate material through a dry mill to obtain magnesium silicate powder, which is then classified.

[0144] 3. Mix the graded magnesium silicate powder with 10mol / L sodium hydroxide solution at a mass volume ratio of 0.9g / mL, and carry out alkali cleaning. After alkali washing treatment under pressure for 80 minutes, the alkali washing ends.

[0145] 4. Filter the alkali washing solution to obtain magnesium-rich silicate precipitates,...

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