Method for smelting magnesium through vacuum thermal reduction of precast pellets

A technology of prefabricated pellets and vacuum heat, applied in the field of metallurgy, can solve the problems that powder and fine materials cannot be produced by smelting magnesium, high-activity segment white is easy to absorb water, storage and transportation costs are high, and it can improve the utilization rate of magnesium resources and system performance. Low consumption, the effect of reducing energy consumption

Active Publication Date: 2013-03-13
LIAONING DONGYU MAGNESIUM RES TECH CO LTD
View PDF3 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] (1) Dolomite needs to be calcined at 1150-1200°C for 2-3 hours to obtain high-activity calcined white; at the same time, about 5% of powder and fines will be produced during the calcination process, which cannot be used for magnesium smelting, resulting in a large amount of waste of resources and energy;
[0004] (2) The high-activity segment white is easy to absorb water and moisture, and it is difficult to store and transport. Generally, it cannot exceed 24 hours, resulting in high storage and transport costs;
[0005] (3) Press calcined white, reducing agent, and fluorite into dense pellets for vacuum reduction, resulting in slow reduction speed, long reduction cycle, low reduction rate, and high production cost
At present, the reduction cycle is mostly 8-12 hours, while the reduction rate of metal magnesium is only about 85%.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0029] According to the dolomite: SiFe: fluorite mass ratio of 100: 12: 2, mix the materials evenly, then add water binder accounting for 3% of the total mass of the materials, and use a disc pelletizer to prepare green pellets with a diameter of 5mm group;

[0030] The green pellets were calcined under a nitrogen protective atmosphere. First, the temperature was raised to 650°C at a rate of 5°C / min, and the temperature was kept constant for 2 hours. Then, the temperature was raised to 1000°C at a rate of 5°C / min. to room temperature to obtain calcined cooked pellets;

[0031] The above-mentioned calcined cooked pellets were thermally reduced at 1150° C. for 1 hour under a vacuum degree of 10 Pa to obtain metallic magnesium, and the reduction rate of metallic magnesium was 91%.

Embodiment 2

[0033] According to the mass ratio of dolomite: aluminum powder: fluorite 100: 13: 2, mix the materials evenly, then add a kaolin binder accounting for 4% of the total mass of the material, and use a disc pelletizer to prepare a pellet with a diameter of 10 mm. raw pellets;

[0034] The green pellets were calcined under a nitrogen protective atmosphere. First, the heating rate was raised to 700°C at a rate of 8°C / min, and the temperature was kept at a constant temperature for 2 hours. At room temperature, calcined cooked pellets are obtained;

[0035] The above-mentioned calcined cooked pellets were thermally reduced at 1150°C for 1.5 hours under a vacuum degree of 10 Pa to obtain metal magnesium, and the reduction rate of metal magnesium was 92%.

Embodiment 3

[0037] According to the dolomite: AlSi alloy powder: fluorite mass ratio of 100: 13: 2, mix the materials evenly, then add polyvinyl alcohol binder accounting for 4% of the total mass of the material, and use a disc pelletizer to prepare a diameter 20mm raw pellets;

[0038] The green pellets were calcined under a nitrogen protective atmosphere. First, the heating rate was raised to 700°C at a rate of 20°C / min, and the temperature was kept constant for 1 hour. Then, the temperature was raised to 950°C at a rate of 10°C / min. to room temperature to obtain calcined cooked pellets;

[0039] The above-mentioned calcined cooked pellets were thermally reduced at 1150° C. for 0.5 h under a vacuum degree of 10 Pa to obtain metal magnesium, and the reduction rate of metal magnesium was 94%.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
diameteraaaaaaaaaa
particle sizeaaaaaaaaaa
diameteraaaaaaaaaa
Login to view more

Abstract

The invention belongs to the field of metallurgy, and in particular relates to a method for smelting magnesium through vacuum thermal reduction of precast pellets. The method comprises the steps of: uniformly mixing dolomite, a reducing agent and fluorite by mass, and then adding a binding agent; preparing raw pellets with diameters of 5-20mm by using a disk pelleting machine; calcining the raw pellets under a nitrogen or argon protection atmosphere to obtain calcined cured pellets; and carrying out vacuum thermal reduction for 0.5-2 hours on the calcined cured pellets at a temperature of 1150 DEG C under the vacuum degree of 10 Pa to obtain the magnesium. The method has the advantages of high raw material utilization rate, high reduction rate, short reduction period, low energy consumption and the like; and compared with the traditional ferrosilicon process for smelting the magnesium, the method realizes the technical upgrading of the ferrosilicon process for smelting.

Description

technical field [0001] The invention belongs to the field of metallurgy, and in particular relates to a method for smelting magnesium by vacuum thermal reduction of prefabricated pellets. Background technique [0002] The production methods of metal magnesium mainly include molten salt electrolysis method using magnesium chloride as raw material and vacuum thermal reduction method using magnesium oxide as raw material. Molten salt electrolysis method is to pass direct current into molten electrolyte containing magnesium chloride and decompose magnesium chloride The method of metal magnesium; the vacuum thermal reduction method is to use metal as a reducing agent under high temperature and vacuum conditions to reduce magnesium oxide to prepare metal magnesium. Due to the abundant dolomite resources in China, the main development of vacuum silicon thermal magnesium smelting, the process includes the following key steps: first, calcining dolomite at high temperature to obtain h...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C22B26/22C22B1/242
Inventor 张廷安豆志河张子木文明刘燕吕国志
Owner LIAONING DONGYU MAGNESIUM RES TECH CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products