TREATMENT METHOD OF CHROMIUM-CONTAINING WASTEWATER

摘要

PROBLEM TO BE SOLVED: To reduce the necessary amount of an added ferrous ion source in a method for solid-liquid separation after reducing Cr⁶⁺ to Cr³⁺ by adding the ferrous ion source to Cr⁶⁺-containing wastewater.;SOLUTION: The ferrous ion source is added to the Cr⁶⁺-containing wastewater to reduce Cr⁶⁺ to Cr³⁺ under a condition where pH is 7-11. The pH of the wastewater is adjusted to 4.5-6.5 without subjecting to solid-liquid separation, and then insolubilized substances are solid-liquid separated and removed from the wastewater.;COPYRIGHT: (C)2004,JPO