Pre-melted desulfurizing agent for refining molten steel and preparation method thereof

Abstract

The invention relates to the technical field of ferrous metallurgy, in particular to a pre-melted desulfurizing agent for refining molten steel, which is characterized by comprising the following components in percentage by weight: 55 to 70 percent of calcium oxide, 10 to 25 percent of high alumina bauxite and 10 to 25 percent of aluminum ash. The aluminum ash is molten slag in aluminum production. A preparation method for the pre-melted desulfurizing agent comprises the following steps: grinding the components into powder of 0 to 2 millimeters, mixing the powder according to a proportion, melting the mixed powder at the high temperature of between 1,450 and 1,600 DEG C, discharging and cooling the melted mixture, and then crushing the mixture into granules of 0 to 70 millimeters to obtain the pre-melted desulfurizing agent. In the impurities, the content of SiO2 is less than or equal to 8 percent, the content of Fe2O3 is less than or equal to 1.5 percent, the content of MgO is less than or equal to 1.2 percent, the content of CaF2 is less than or equal to 3 percent, and the content of moisture is less than or equal to 0.5 percent. The pre-melted desulfurizing agent has the advantages that: (1) the melting point is low, and the melting speed is high; (2) the desulfurizing rate can reach over 60 percent; (3) the using amount of the desulfurizing agent is reduced by about 50 percent; (4) the desulfurizing agent can be used for desulfurizing molten steel and molten iron; and (5) the desulfurizing agent is fluorine-free or has micro-fluorine, and is favorable for environmental protection.

Description

technical field [0001] The invention relates to the technical field of iron and steel metallurgy, in particular to a premelted desulfurizer for molten steel refining and a preparation method thereof. Background technique [0002] At present, there are two main types of desulfurizers used for refining molten steel: one is mainly composed of lime and fluorite, and the desulfurization effect of this desulfurizer is ideal, but the content of fluorite in the components is relatively high. It will seriously affect the service life of the furnace body or tank lining refractories, and it is easy to cause environmental pollution and bring harm to humans and organisms; the other type is mainly composed of lime and bauxite. After the lime and bauxite are melted Calcium aluminate is generated, which has a lower melting point, so the slagging speed is faster, and because the fluorite content is less, the corrosion of refractory materials is lighter. [0003] In steelmaking production, d...

AI Technical Summary

Problems solved by technology

Although this pre-melted molten steel cleaning agent has achieved a certain desulfurization effect, the content of fluorite is high, and the corrosion of refractory materials is serious, which affects the service life of the furnace lining or tank lining, and the fluorine content in the slag is high, which is not conducive to environmental protection. , easy to cause environmental pollution, bring harm to human beings and living things