Explanation

The operation of adjusting slag composition, alkalinity, viscosity and reaction ability in steel and iron production is aimed at smelting steel or iron that meets the requirements of composition and temperature through slag metal reaction. For example, during oxygen top blowing converter sleelmaking steelmaking, the purpose of oxygen blowing is to generate slag with enough flow ability and alkalinity, so as to reduce the sulfur and phosphorus content in steel below the upper control limit, and at the same time reduce the amount of splashing and spilling slag during oxygen blowing as much as possible. The main methods are single flooding method, double slag method and double slag retention slag method. In different stages of steelmaking, slag with different characteristics needs to be obtained. For example, in the oxidation period of steelmaking, it is hoped to form oxidized slag that can oxidize some metals; During the reduction period of steelmaking, it is hoped to form reduced slag that can deoxidation the metal phase. According to the relative content of acid oxides (silica and alumina) and basic oxides (calcium oxide and magnesium oxide) in the slag, it can be divided into acid slag and basic slag. In the process of steelmaking and converting, due to the role of oxygen jet and molten pool, a three-phase emulsion of gas molten hawthorn steel liquid can be formed. The total volume of small bubbles dispersed in slag is several times or even dozens of times more than the volume of slag. The molten slag becomes a liquid film and encloses bubbles, which makes the molten slag foam and expand. Such molten slag is called foam slag. electric arc furnace steelmaking often uses long arc foam slag operation.

Classification