Process engineering considerations in the design of the water treatment plant for the Rum Jungle rehabilitation project

The Rum Jungle rehabilitation programme includes the treatment of around 4 million cubic metres of water that has been polluted by previous treatment operations and acidic seepage containing heavy metal salts from slowly oxidising overburden dumps. The water to be treated is of low pH and contains high sulphate levels. Project rehabilitation criteria and the basic chemistry of metal salts in solution were considered in arriving at the final process design. In order to achieve a cost effective plant design, the process was translated into a flow sheet that used unit operations that are more typical of the extractive metallurgical than the traditional water treatment industry. Consideration of the unit operations and the operating aspects of the plant are discussed