Slag from aluminum smelting for making clean steel and method for preparing same

Abstract

The invention relates to the steel-smelting technology field, and in a more accurate way it is a neutral aluminium slag used in steel-smelting and refining and the preparing method. The neutral aluminium slag is used in the clean steel-melting, and the character is that it is comprised with the following substance and with their proportion wy weight is: aluminum powder, 23-27; fluorite, 10-22%; remelting slag, 30-40%; carbonate, 8-15% and reducer, 3-8%. The invention is characterized by the simple preparing method, the good practicability of product, the easy manipulation of the process, the good reducing power to the ladle and steel slag, the good heat-retaining power of the surface of steel liquid. The neutral aluminium slag is added in the ladle after the tapping of steel liquid, the adding quantity is 3-5kg / t.s, and the ferric oxide content in the ladle can be decreased to below 10%, and can be at an extreme level: 1-3%, the alkalinity can reach to 4-6. The T[O] content in the steel dealt with molten steel can reach to lower than 50ppm, and the extreme low content can reach to 30ppm. There is no pollution in the production area and the purity of steel is improved.

Description

[technical field] [0001] The invention relates to the technical field of steelmaking, and more precisely relates to a medium aluminum slag for steelmaking and refining and a preparation method thereof. [Background technique] [0002] In the refining process outside the furnace of steelmaking, the molten steel is tapped from the primary furnace such as the smelting furnace or electric furnace and enters the ladle, and then the molten steel is deoxidized, desulfurized, and inclusions are removed to improve the purity of the steel and meet the quality requirements of users. The deoxidation of steel is usually carried out in the ladle, and some products of deoxidation are discharged by removing the slag of the ladle. However, the reoxidation of steel and dissolved alloys may be carried out in the ladle, in the tundish and Occurs in continuous casting moulds, or during individual transfer operations, which can adversely affect the final purity in the steel. [Content of the inve...

AI Technical Summary

Problems solved by technology

The deoxidation of steel is usually carried out in the ladle, and some products of deoxidation are discharged by removing the slag of the ladle. However, the reoxidation of steel and dissolved alloys may be carried out in the ladle, in the tundish and Occurs in continuous casting moulds, or during individual transfer operations, which can adversely affect the final purity in the steel.