Efficient composite desulfurization agent, preparation method and applications thereof

Abstract

The present invention provides an efficient composite desulfurization agent, a preparation method and applications thereof, wherein the efficient composite desulfurization agent comprises, by mass, 65-75% of quick lime, less than or equal to 10% of limestone, 5-10% of soda ash, less than or equal to 10% of fluorite, and less than or equal to 5% of graphite. According to the present invention, the premix, ie., the composite desulfurization agent, is transported by a tank car and is subjected to pressurization conveying to a desulfurization agent bin, and during the desulfurization treatment, the desulfurization agent is introduced into a spraying-blowing tank from the desulfurization agent bin, and is pressurized, and the pressurized desulfurization agent is sprayed into liquid iron in a spraying-blowing manner so as to perform desulfurization; and compared to the unimproved Baosteel steelmaking plant torpedo car desulfurization agent, the efficient composite desulfurization agent of the present invention has the following characteristics that the consumption is significantly reduced (the maximum unit consumption decrease of the desulfurization agent during the application is 2.95 Kg / t) under the same liquid iron condition and the same desulfurization requirement, and due to the significantly reduced desulfurization agent consumption, the temperature decrease of the desulfurization treatment is significantly decreased (the temperature decrease is decreased by 9.43 DEG C / torpedo car).

Description

technical field [0001] The invention belongs to the technical field of steelmaking technology, and relates to a high-efficiency composite desulfurizer and its preparation method and application. The high-efficiency composite desulfurizer is a CaO-based composite desulfurizer, and specifically relates to the technical field of molten iron pretreatment technology, which is used to remove of sulfur. Background technique [0002] The harm of sulfur to steel is mainly reflected in the hot embrittlement and anisotropy of steel. During the heating process of steel, the sulfur insoluble in △Fe is precipitated on the grain boundary in the form of FeS, and the melting point of FeS is 1190°C. At 900-1200°C, it will also form a lower melting point eutectic with FeO, which will cause the steel to fracture along the grain boundary when heated, that is, hot embrittlement; because the sulfide inclusions are very soft, they are easily deformed during the heating process of the steel, and al...

AI Technical Summary

Problems solved by technology

However, the temperature loss of molten iron is relatively large during the treatment process, and the increase in oxygen potential is not conducive to desulfurization

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