Method for desulfurization of molten steel having slag of high oxygen potential

摘要

PURPOSE: A method for desulfurizing molten iron is provided, which is capable of increasing cleanliness of molten iron in the series of steelmaking process by performing desiliconization operation using iron oxide before performing desulfurization treatment. CONSTITUTION: The method comprises a step of injecting limestone based desulfurizer at a rate of 80 to 120 kg/min, and maintaining a lance dipping depth ratio to 0.35 to 0.45; a step of injecting limestone based desulfurizer, sodium carbonate and soda ash at a rate of 50 to 70 kg/min respectively for post-mixing, and maintaining a lance dipping depth ratio to 0.75 to 0.85; and a step of injecting sodium carbonate and soda ash at a rate of 50 to 70 kg/min, and maintaining a lance dipping depth ratio to 0.85 to 0.95.