Microfiltration Treatment of Acid Rock Drainage

Traditional treatment of acid rock drainage consists of pH adjustment, clarification, and sand filtration. Then the pH is adjusted back to a normal range and the effluent is discharged. These operations are prone to clarifier upsets and filter clogging. A ceramic MF membrane was used to replace the clarifier and sand filter. This membrane was operated in a cross flow mode of operation with a high cross flow velocity of 10-20 feet per second. This cross flow provided scouring effects that helped prevent membrane fouling. The ceramic MF membrane proved to be a reliable and cost effective method of treating the acid rock drainage stream.