Andre Rieger

Optimization Study for Treatment of Acid Mine Drainage Using Membrane Technology

The use of membrane technology in the treatment of Acid Mine Drainage (AMD) can result in reduction of chemical usage and sludge production making the treatment process more environmentally friendly. This study deals with the optimization of membrane filtration performance in the treatment of AMD using two nanofiltration (NF) membranes (NF99 and DK) and one reverse osmosis (RO). All membranes were used in various tests treating a model solution at two different concentration levels in order to cover the concentration of actual AMD found in the mining industry. The main parameters which were studied to determine the optimal condition for AMD filtration are pressure, pH, temperature, and flow rate. Pressure and temperature were found to have a considerable influence on flux, while rejection was only slightly influenced by pressure. The feed flow rate had no effect on rejection. The highest flux with moderate rejection was determined for NF99 while RO had the lowest flux but highest rejection. Therefore, NF is preferable for AMD treatment due to lowest energy consumption. The treatment has also been tried on a large scale to check its applicability at a commercial scale. Finally, PHREEQC has been used to determine the scaling risk in the prepared AMD.