DESULFURIZING AND DEPHOSPHORIZING AGENT FOR STEELMAKING

摘要

PURPOSE:To improve reactivity and effectiveness by mixing calcium carbonate powder and/or calcium hydroxide powder with calcium oxide or carbide or mixed powder thereof and making a bulky-state. CONSTITUTION:With the calcium oxide powder or the carbide powder or mixed powder thereof, either or both of the calcium carbonate powder and the calcium hydroxide powder are mixed and made to a bulky-state to prepare a desulfurizing and dephosphorizing agent. As the desulfurizing and dephosphorizing agent in this method is the bulky-state when charging to a steelmaking furnace, the agent can reach to molten slag and molten steel like the ordinary agent. However, by mixing the calcium carbonate or the calcium hydroxide, heat decomposition is developed with heat of the molten slag or the molten steel, and by releasing carbon dioxide or steam, the bulky desulfurizing and dephosphorizing agent is broken and made to small pieces. Therefore, contact area between the agent and the molten slag and molten steel is enlarged and the reaction rate is increased.