Compound iron melt desulfurizing agent and method of preparing the same

Abstract

The invention relates to a composite type molten iron desulfurizer and a preparation method thereof, which relates to a novel desulfurizer used for desulfurizing of molten iron or molten steel and a manufacturing process thereof. The components and the weight percentage ratio of the composite type molten iron desulfurizer are: 70.0 to 75.0 percent of CaO, 2.0 to 3.0 percent of TMg, 10.0 to 12.0 percent of CaC2, 8.0 to 10.0 percent of NaHCO3, 0.5 to 1.5 percent of Al, C 1.0 to 4.0 percent of C, 0 to 5.0 percent of CaF2, less than and equal to 0.18 percent of S, less than and equal to 0.10 percent of P and the rest of impurities; the finished product of the desulfurizer is powdery. The preparation method of the sulfurizer is that lime, passivated magnesium powders, calcium carbide, alkali carbonate additives, aluminum powders, graphite or charcoal, fluorite, etc. are utilized as the raw materials and are mixed evenly according to a certain weight percentage, dried and pretreated; passivated liquid is prepared; then the passivated liquid is poured into the materials to be stirred till the materials are dried, and the materials are cooled naturally and ground to make into powdery finished product. Compared with the prior art, the composite type desulfurizer and the preparation method thereof of the invention have the following advantages: short time required by the desulfurizing treatment, small quantity of slags, small temperature drop and good desulfurizing effect; low comprehensive using cost; simple production process and wide resources of the raw materials; improvement of slag forms during molten iron desulfurizing and reduction of iron loss of the molten iron. The calcium carbide, especially the magnesium powders (particles) are the products of high energy consumption, the effect of energy saving is achieved because the composite type molten iron desulfurizer of the invention correspondingly lowers the using amount of CaC2 or Mg.

Description

Technical field [0001] The invention belongs to the technical field of molten iron desulfurizers in the metallurgical steelmaking process, and in particular relates to a composite molten iron desulfurizer capable of meeting the requirements of deep desulfurization of molten iron and reducing iron loss in the process of molten iron desulfurization and a preparation method thereof. Background technique [0002] Sulfur in steel has adverse effects on the performance of steel, reduces the plasticity and toughness of steel, and affects the surface and internal quality of steel. The steel required by modern industry requires that the sulfur content should be ≤0.015%, while the sulfur content of pipeline steel is limited to 0.002-0.005%. In order to reduce the sulfur content in steel and improve the quality level of steel, the desulfurization technology of hot metal treatment outside the furnace has become an indispensable link in the steelmaking process. Traditional hot metal des...

AI Technical Summary

Problems solved by technology

But its disadvantage is that the production of magnesium-barium alloy requires special equipment, such as intermediate frequency electric furnace, jaw crusher, etc., which increases the cost of magnesium-based desulfurizer

The alloy has strong deoxidation and desulfurization capabilities, but the production and use costs are relatively high