Dephosphorizing agent for low-silicon molten iron steelmaking and preparation and using method thereof

Abstract

The invention belongs to the field of steel metallurgy technology and resource recycling, and relates to a dephosphorizing agent for low-silicon molten iron steelmaking and a preparation method and using method of the dephosphorizing agent. Magnesium reducing slag, lime particles and scale are mixed according to the mass ratio being (0.5-3):(1-2):(0.5-3), fully and uniformly mixed by a ball mill, added with a binder, and pressed by a ball press to obtain the dephosphorizing agent with the particle size being 1-60mm, and the dephosphorizing agent comprises, by mass, 25%-75% of CaO, 15%-65% of Fe2O3, 5%-25 % of SiO2, 1%-8% of MgO and 0.3%-3% of Al2O3. The proportion of the magnesium reducing slag is adjusted according to the silicon content of the molten iron in the preparation process, so that a multi-element dephosphorization slag system with low melting point and high fluidity can be formed. Recycling application of magnesium reduction slag can be achieved, the problems of difficult slagging, high slag melting point, likely gun sticking and the like of low-silicon molten iron steel making can be solved, the dephosphorization slagging speed is increased by 10% or more, and the dephosphorization rate is increased by 5% or more.

Description

technical field [0001] The invention belongs to the field of iron and steel metallurgy technology and resource recycling, and relates to a dephosphorization agent for low-silicon molten iron steelmaking and a preparation and use method thereof. Background technique [0002] my country is the largest magnesium producer in the world, accounting for about 80% of the world's total output. For every ton of crude magnesium produced, about 5-8 tons of magnesium reduction slag is produced, the main components of which are CaO and SiO 2 , MgO, Fe 2 o 3 . At present, a large amount of magnesium reduction slag has not been effectively utilized, and is still discharged and piled up randomly, resulting in waste of resources. The resource treatment and reuse of magnesium reduction slag has become a key link that limits the sustainable development of the magnesium industry. [0003] The production of low-silicon hot metal by blast furnace can bring huge economic benefits to iron and st...

AI Technical Summary

Problems solved by technology

[0005] In order to solve the above problems, the present invention provides a dephosphorization agent for low-silicon molten iron steelmaking and its preparation and use method. The present invention can not only realize the resource utilization of magnesium reduction slag, but also solve the Difficulty in slagging, easy sticking to the gun, sticking to the flue, and low dephosphorization rate due to low melting point slagging substances