Method for producing high-purity pure iron

Abstract

The invention provides a method for producing high-purity pure iron, which comprises the following steps of: (1) preliminary desulphurization of molten iron: controlling the sulphur content of molten iron charged into a revolving furnace at 0.002%-0.015%; (2) smelting of the revolving furnace: dephosphorizing by using the double slag process, tapping slag after dephosphorization, changing slag, controlling C to be less than 0.03% and P to be less than 0.008% at blowing end, carrying out slag-blocked tapping and aluminium deoxidation, and hanging pots at temperature of above 1635 DEG C; (3) slagging off: removing more than 95% of oxidizing slag; (4) RH deep decarburization: controlling RH charging temperature to be above 1615 DEG C, controlling C to be less than 0.002% and Als to be from 0.020% to 0.035% at smelting end, and controlling the discharging temperature to be above 1645 DEG C; (5) LF (Low Frequency) deep decarburization: adding a deep dephosphorizing agent before entering anLF station, stirring with argon gas, adding a slagging constituent after entering the LF station, stirring with a great amount of argon gas, controlling C to be less than 0.0025%, S to be less than 0.0015%, Als to be less than 0.010% and discharging temperature to be from 1600 DEG C to 1605 DEG C; and (6) continuous casting of plate blanks. The invention has the advantages of low production cost and high efficiency; and the purity of the produced product reaches more than 99.9%.

Description

technical field [0001] The invention belongs to the technical field of steelmaking, in particular to a large-scale production method of high-purity industrial pure iron. Background technique [0002] Pure iron is an important raw material for the production of magnetic materials, electrothermal alloys, precision alloys and special metal materials. As the requirements for precision alloys and magnetic components are getting higher and higher, cutting-edge high-tech products have higher and higher requirements for purity. The high-purity industrial pure iron produced in Japan is manufactured by electrolysis, and the purity can reach 99.9% iron content, but the price is too high. [0003] my country adopts GB9971 and GB6983 to produce raw material pure iron and industrial pure iron, which are generally manufactured by converter or converter + refining outside the furnace, but the purity is not high, the impurity elements of pure iron are high, and the purity of the actual quali...

AI Technical Summary

Problems solved by technology

In this method, scrap steel is melted into mother liquor and poured into a ladle. After removing slag, it is placed in a VOD refining furnace for refining. Due to the lack of VOD equipment, popularization of production is also limited, and its purity is not high, and it is also less than 99.7%.

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