Abstract: Dexing Copper Mine is the largest open-pit copper mine in Asia.The acid drainage produced in its mine slope, workface and dump is characterized by many pollution sources, wide scope and greatly varying water quality, leading to a great difficulty in the control of acid drainage treatment system.The paper mainly describes how the mine has controlled and reduced the acid drainage production and discharge, and improved its treatment capacity by the control system optimization of acid drainage treatment and the adoption of source reduction, process control and end treatment methods.

Key words: Acid drainage, Treatment system, Control optimization