TREATMENT OF MOLTEN BATH TO BE SUBJECTED TO DEPHOSPHORIZATION REGENERATION OF CONVERTER WASTE SLAG AND RECOVERY OF VALUABLE COMPONENTS

摘要

PURPOSE:To regenerate converter waste slag and to recover valuable cmponents effectively by regenerating slag by repetition of dephosphorization (de-P)(V) of the converter waste slag in an electric arc furnace and shifting and slagging off the enriched P (V) in the bath to soda ash type slag. CONSTITUTION:The molten steel from a blast furnace 1 is shifted into an electric arc furnace 2 for slag dephosphorization, and the converter slags 5, and molten ingot dephosphorization slag 6 formed in bottom blown converters 3, 4 are introduced as converter waste slag into the furnace 2. The slag is subjected to agitating and heating in the furnace 2 and the P2O5, V2O5 in the waste slag are reduced by the C, Si in the bath, and the resultant reduced slag 7 is reutilized for part of the glag forming agent for the furnace 3 for Q-BOP ordinary blowing, or furnace 4 for Q-BOP molten ingot dephosphorization. On the other hand, the molten iron enriched of P and V by the reduction is subjected to a de-P treatment 8 by blowing Na2CO3 into the bath, whereby the soda ash type slag 9 contg. P, V is removed. The remaining molten iron is reiteratively utilized, and the slag 9 is recovered as Fe-V, Fe-P.