METHOD FOR REGENERATING WATER FROM PLATING WASTEWATER, AND METHOD FOR RECOVERING SILVER FROM PLATING WASTEWATER

摘要

PROBLEM TO BE SOLVED: To provide a method for regenerating water from plating wastewater capable of achieving resource saving and environmental protection by reusing plating wastewater containing silver and cyan as rinsing water in a plating process, and a method for recovering silver from plating wastewater capable of improving a recovery rate of silver from plating water containing silver and cyan, and improving filterability when recovering.SOLUTION: The method for regenerating water from plating wastewater comprises treating plating wastewater containing silver and cyan and having a cyan-containing mole amount greater than an equivalent mole ratio (Ag:CN=1 mol:2 mol) of silver cyanide complex ([Ag(CN)]) with a reverse osmotic membrane to reuse obtained permeated water as rising water in a plating process.The method for recovering silver from plating wastewater comprises treating plating wastewater containing silver and cyan with a reverse osmotic membrane, and adding a hypochlorite to obtained concentrated water to decompose cyan and recover silver.