Converter steelmaking process usually takes hot metal, scrap steel and ferroalloy as the main raw materials, without the aid of external energy, relying on the physical heat of liquid iron itself and the chemical reaction between liquid iron components to generate heat and complete the steelmaking process in the converter.
According to different refractories, the converter is divided into acid and basic, according to the part of gas blowing into the furnace there are top blowing, bottom blowing and side blowing; According to the gas type, it is divided into air converter and oxygen converter. The basic oxygen top blown and top and bottom blown converter is the most commonly used steelmaking equipment because of its high production speed, large output, high single furnace output, low cost and less investment. Converter is mainly used for the production of carbon steel, alloy steel and copper and nickel smelting.
Usually, oxygen top-blown converter is the most common steel making equipment in converter. The entire process is as follows:
First put the scrap steel into the furnace, then pour the hot metal, and add the appropriate amount of slag-making materials (such as quicklime, etc.). After feeding, the oxygen spray lance is inserted into the furnace from the top of the furnace, and the oxygen is blown into the air (hyperbaric oxygen with a purity greater than 99%), so that it directly oxidizes the hot metal with high temperature to remove impurities. The replacement of air with pure oxygen can overcome the disadvantages of brittleness of steel due to the influence of nitrogen in the air, and the removal of heat by nitrogen. After removing most of the sulfur and phosphorus, when the composition and temperature of the molten steel meet the requirements, the blowing is stopped, the spray gun is raised, and the steel is ready to be produced. The furnace body is tilted, the molten steel is injected into the ladle from the outlet, and the deoxidizer is added to deoxidize and adjust the composition. After the molten steel is qualified, it can be poured into steel castings or ingots, and the ingots can be rolled into various steels.