Chemical speciation of pollutants in waters of Dexing Copper Mine area by using chemical equilibrium modeI-MINTEQA2

The MINTEQ program is used on the speciation of pollulants in waters of Dexing Copper Mine area．Four kinds of waters are encountered．The results show that all pollutants are dissolved phase in typical acid mine drainage，with pH increasing，the iron，aluminum and copper would be precipitated at different pH values．After receiving alkaline wastewater，pH value of the Dawu River water goes higher，resulting in increasing amount of pollutants bounded in solid phase．For the mixed water，the speciation results show that at mixing ratio(alkaline water to acid water)of 8 to 9，neutral water will be gained and different pollutants will precipitate completely at different mixing ratios．