TREATING METHOD FOR WASTE CHROMATE LIQUID

摘要

PROBLEM TO BE SOLVED: To provide a treating method for a waste chromate liquid which is capable of inexpensively and effectively separating and removing a Cr component even from the waste chromate liquid containing many organic acid components. SOLUTION: A Cr settling accelerator containing at least either of Ca and Mg components is added to the waste chromate liquid containing the many organic acid components and the pH of the waste chromate liquid treated is maintained at >=9, by which the Cr component is settled and the concentration of the dissolved Cr component in the liquid is lowered. The pH of the waste liquid when progressing the settling reaction is maintained at >=9, by which the rapid progression of the settling reaction of the Cr component even in the waste liquid containing the many organic acid components is made possible and the concentration of the dissolved Cr in the liquid may be effectively lowered.