CN1049381A

CN1049381A - Obtaining metal magnesium with vacuum-thermal method by burning magnesite slightly in magnesite

Info

Publication number: CN1049381A
Application number: CN 90105613
Authority: CN
Inventors: 颜志明; 颜志仁; 吴秀; 刘雅娴; 史平
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-01-25
Filing date: 1990-01-25
Publication date: 1991-02-20

Abstract

The invention belongs to the vacuum metallurgy technology field, it is characterized in that adopting the magnesite caustic-calcined magnesite as raw material, the mixed powder that also can adopt magnesite and the two calcined material of dolomite mineral is as raw material, with addition of the ferrosilicon powder of the theoretical silicon consumption of 90-110% reduction reaction or industrial silica fume catalyzer as the multi-element compounds of reductive agent and a small amount of Ca, Mg, F, behind mixing, the group of pressure or briquetting, put into the heat-resisting retort of sealing, under vacuum tightness 0.1-30Pa, temperature 1150-1250 ℃ of constant temperature 5-10 hour condition, high yield and high quality is produced MAGNESIUM METAL.

Description

Obtaining metal magnesium with vacuum-thermal method by burning magnesite slightly in magnesite

The invention belongs to the vacuum metallurgy technology field, be one and be used for the production of vacuum-thermal method refining magnesium, can increase substantially novel process, the new technology of magnesium productive rate and its production cost of reduction.

MAGNESIUM METAL industrialized producing technology method has two both at home and abroad at present; A kind of is to adopt magnesite to make magnesium chloride fused salt electricity Jie method of raw material.Another kind is to adopt rhombspar to forge white raw material is made reductive agent with ferrosilicon etc. the vacuum-thermal method of doing.Claim Pidgeon process again, this method continues to use four during the last ten years, and no major reform and breakthrough on Technology and key equipment still exist the retort diameter to be difficult to enlarge, and jar quantity is many, per unit area yield is low, the life-span is short, production cost is high, and operation is shortcoming intermittently.

The main chemical reactions formula of production of magnesium by pidgeonprocess is as follows:

When adopting 75% ferrosilicon powder to make reductive agent be:

When adopting silica flour to make reductive agent be:

Calculate and learn from above-mentioned (1), (2) reaction formula: the highest theoretical magnesium productive rate of Pidgeon process coal magnesium has only 21kg and 22kg magnesium/every 100kg scale material.In actual production, because influences such as material purity and reductive agent grade, it is impure many that particularly natural dolomite mineral is forged white powder, it is low to contain Mgo, it is too high to contain cao, makes Mgo/cao composition ratio less than 1, the actual magnesium productive rate of Gu Pijiangfalianmeichang, claim good magnesium factory of Furukawa Electronic also to have only 17-20kg magnesium/100kg to feed intake, domestic tens tame medium and small magnesium factories are then low to having only 8-17kg magnesium/100kg to feed intake.

The inventor is on chemical reaction Theoretical Calculation, analysis and experimental basis, set up and realized that employing magnesite caustic-calcined magnesite powder or magnesite add the two calcining powder of dolomite mineral and makes raw material, make reductive agent with silica flour or ferrosilicon powder, the multi-element compounds that adds a small amount of calcic, magnesium, fluorine is made the vacuum-thermal method refining magnesium novel process technology of catalyzer.The main chemical reactions formula of relevant this magnesite caustic-calcined magnesite vacuum magnesium-smelting silicothermic process is expressed as follows:

Learn from above-mentioned (3) and the calculating of (4) reaction formula: the highest theoretical value magnesium productive rate of the present invention can exceed 32kg and 44kg magnesium/every 100kg scale material.Higher 45% to 1 times than production of magnesium by pidgeonprocess theoretical yield.Utilize Technology of the present invention and prescription, certain type approval test device initial stage is installed test run, have under the very poor condition half material also not the magnesium productive rate during reduction reaction reached the every 100kg of 21kg/ and fed intake, so comparable existing production of magnesium by pidgeonprocess factory unit productive rate is high more than 30% to 1 times.

The said magnesium-smelting production technology flow process of the present invention condition and being characterized as, employing contains the magnesite caustic-calcined magnesite powder of MgO% grade 〉=35% as the refining magnesium raw material, the mixed powder that also can adopt dolomite mineral and the two calcined material of magnesite is as the refining magnesium raw material, cooperate an amount of ferrosilicon powder or industrial silica fume etc. as reductive agent, through the fine grinding mixing, put into the refractory alloy retort behind briquetting or the briquetting, at vacuum tightness 0.1-30pa, under the temperature 1150-1250 ℃ of constant temperature 5-10 hour condition, carry out high yield, the high-quality production of MAGNESIUM METAL, magnesium purity reaches about 99.95%.

Above-mentioned refining magnesium raw material magnesite, be to be crushed to granularity to be narrower than caustic-calcined magnesite powder more than-120 orders after 850-1150 ℃ of calcining, cooling, its relevant composition is: MgO 〉=85%, (K+Na) 2O≤0.15%, burn decrement rate≤1.5%.When adopting magnesite and dolomite mineral to forge white compound to make raw material, its relevant component is: contain MgO40-80%, and CaO10-50%, (K+Na) 2O≤0.15%, burn decrement rate≤1.5%, granularity is narrower than more than-120 orders.

Above-mentioned reductive agent adopts ferrosilicon powder or industrial silica fume etc., its granularity all is narrower than more than-120 orders, its consumption proportion is the 90-110% of the theoretical consumption of chemical reduction reaction, its best proportioning value is the physicochemical property according to raw material and reductive agent, at the magnesium productive rate, the starting material unit consumption, it is fixed to get in the intersecting area of cost curve.

The present invention adds multi-element compounds such as accounting for total stuff amount 1-5% calcium magnesium fluorine, as catalyzer for improving magnesium reduction speed of response and productive rate when batching.

Claims

1, the present invention is used for the production of vacuum-thermal method refining magnesium, it is characterized in that: adopt to contain the higher magnesite caustic-calcined magnesite powder of MgO% grade as the refining magnesium raw material, the mixed powder that also can adopt dolomite mineral and the two calcined material of magnesite is as the refining magnesium raw material, with addition of an amount of ferrosilicon powder or industrial silica fume etc. as reductive agent, through levigate mixing, put into the refractory alloy retort behind briquetting or the briquetting, at vacuum tightness 0.1-30pa, under the temperature 1150-1250 ℃ of constant temperature 5-10 hour condition, carry out the high yield and high quality production of MAGNESIUM METAL.

2, according to the regulation of claim 1, it is characterized in that: said refining magnesium raw material magnesite is after 850-1150 ℃ of calcining cooling, be crushed to granularity and be narrower than the above caustic-calcined magnesite powder of-120 orders, its relevant composition is: Mgo% 〉=85%, (K+Na) 2O≤0.15%.

3, according to the regulation of claim 1, it is characterized in that: said refining magnesium raw material also can adopt the two compound of dolomite mineral calcining and magnesite caustic-calcined magnesite as refining magnesium raw material, its relevant composition is: Mgo40-80%, cao10-50%, (K+Na) 2o≤0.15%, burn decrement rate≤1.5%, granularity are narrower than more than-120 orders.

4, according to the regulation of claim 1, it is characterized in that: reductive agent adopts ferrosilicon powder or industrial silica fume etc., its granularity all is narrower than more than-120 orders, its consumption proportion is the 90-110% of the theoretical consumption of chemical reduction reaction, its best proportioning value is the physicochemical property according to raw material and reductive agent, and it is fixed to get in the intersecting area of magnesium productive rate, starting material unit consumption, energy consumption cost curve.

5, a kind of reagent that improves magnesium reduction speed of response and productive rate is characterized in that adding the multi-element compounds such as calcium magnesium fluorine that account for total amount 1-5%, as the catalyzer of vacuum-thermal method refining magnesium in batching.