1、 Overview:

With the increasing demand for high-quality steel in the market, the sulfur content of molten steel used in steel-making process is more and more strict. Domestic iron and steel enterprises continue to transform and improve their steel-making equipment and process. The development and application of two-step steelmaking laid a foundation for improving the quality and output of steel. However, some steelmaking workshops still use obsolete equipment due to various factors. In order to meet the needs of the market and improve the quality of steel, it is necessary to adjust the process and auxiliary materials used and their application.

Most of the molten steel after primary refining in the furnace usually does not meet the factory requirements. Therefore, it is necessary to modify and adjust the slag during tapping and stir for a short time to strengthen the absorption of sulfur and other inclusions in molten steel.

2、 Theoretical basis

Melt structure design of premelted refining slag in order to meet the process requirements of high-efficiency converter refining and high-efficiency continuous casting, the composition of slag system was prepared by thermodynamic data, dynamic characteristics and coexistence theory of slag structure. When alkaline reducing slag contacts with molten steel, the actual value of oxygen and sulfur in molten steel is greater than that of equilibrium with slag, which makes oxygen and sulfur in molten steel diffuse into slag. Cao, Al, O. and other components in slag are all composed of oxides, so the interfacial tension between them is small and easy to combine into low melting point compounds. However, the interfacial tension between molten steel and deoxidized products is greater than that between slag and deoxidation products. Therefore, deoxidation products can be easily removed from molten steel.

3、 Brief introduction of new type ladle desulfurizer

The premelted refining slag developed by our company is used for desulphurization of ladle. According to the metallurgical principle and the physicochemical law reflected by slag and molten steel, the premelted refining slag is composed of high-quality intensified desulfurizer, reaction promoter, gas generator, cosolvent additive and other materials according to the basic composition of different molten steel.

4、 Product features

1. The slag forming speed of the product is fast, which can meet the needs of production rhythm.

2. The viscosity of the product is low after melting, and the slag slides down naturally along with the ladle wall, so that the ailo, composition and other slag components in the slag are sintered at the same time to protect the ladle lining.

3. The product has rapid desulfurization reaction, high activity and good fluidity in the ladle. It can separate molten steel from slag at the same time

4. The product has stable chemical activity and low melting point. It melts immediately when it contacts with molten steel. Desulfurization is reflected in the simultaneous process of solid-liquid and liquid-liquid.