Hot metal pretreatment dephosphorization agent and preparation method thereof

Abstract

The invention discloses a hot metal pretreatment dephosphorization agent and a preparation method thereof. In mass percent, a formula of the dephosphorization agent comprises: 30-70% of drying sintering nose electric precipitation ash, 10-30% of lime CaCO3 and 10-40% of iron oxide; binary basicity CaO / SiO2 of the hot metal pretreatment dephosphorization agent is 3-4, and alkali chloride content is 5-15%; in mass percent, the total content of four substances, namely CaO, Fe, KCl and NaCl, in the dry sintering nose electric precipitation ash is not less than 60%, wherein the content of alkali chlorides is not less than 10%; and the iron oxide is one or more of sintered ore, iron ore powder, converter dust, electric furnace dust and oxidized scale. Ingredients of the formula of the dephosphorization agent are dried and treated and then are ground until particle size is below 1mm, and uniform mixing is carried out.

Description

technical field [0001] The invention belongs to the technical field of iron and steel metallurgy, in particular to a molten iron pretreatment dephosphorization agent and a preparation method thereof. Background technique [0002] Iron and steel metallurgical sintering head electric dust is the flue gas and dust collected by the electric dust collector during the iron ore sintering process, and its production volume accounts for about 2%-4% of the sinter output. A joint enterprise with an annual output of 10 million tons of steel produces about 300,000 tons of electrostatic precipitator ash for sintering heads per year. Iron ore raw materials often contain impurity elements such as potassium, sodium, and fluorine, and the resulting sintering dust contains high potassium and sodium content. The sintered ash is directly returned to the blast furnace for recycling, which will lead to the gradual enrichment of elements such as potassium and sodium in it. It may lead to corrosio...

AI Technical Summary

Problems solved by technology

[0004] ①The initial slagging speed is slow;

[0005] ②The cost of dephosphorization agent is high;

[0006] ③The dephosphorization agent contains 5-20% CaF 2 , seriously erodes refractory materials, and the fluoride in dephosphorization slag pollutes the soil, which is not conducive to environmental protection

The disadvantage of this dephosphorization agent is that the dephosphorization agent contains CaF 2 , will adversely affect the environment

The dephosphorization agent is B 2 o 3 Alternative Flux CaF 2 , and B 2 o 3 The fluxing effect is obvious, not only does not pollute the environment, but the dephosphorization slag contains boron and phosphorus elements that can be used to make boron-phosphorus compound fertilizers, but a certain amount of boron elements will remain in the molten iron after dephosphorization, which will affect the quenching of steel. adverse effect on permeability

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