RECYCLING METHOD OF BLAST FURNACE SLAG

摘要

PURPOSE: A recycling method of blast furnace slag is provided. When slag is treated with acid, several metal components reacting with acid of the slag are dissolved and Si component insoluble in acid is isolated as high purity solid state silica. The mixed metal salt solution can be used as fertilizer, snow removing agent or hygroscopic agent after removing acid by distillation. CONSTITUTION: The recycling method of blast furnace slag comprises the steps of: a) slag is reacted with acid solution such as nitric acid, sulfuric acid and hydrochloric acid at room temperature to get metal salt mixture such as Ca(NO3)2, CaCl2, and CaSO4 b) filtering process to separate solid state material from liquid state material c) recovering the silica by distillation and cleaning of the remaining acid.