Bench-scale study of acid mine drainage treatment using local neutralisation agents

Bench-scale experiments were conducted to evaluate the treatment performance of alternative alkaline media; serpentinite and concrete waste compared to conventional treatment with common neutralisation agents namely hydrated lime and limestone in terms of reducing acidity and metals concentrations in acid mine drainage (AMD) samples taken from effluent of an abandoned copper mine located in Mamut, Sabah. Parameters tested in these experiments include particle size and mass of the materials. The tests were performed using a jar tester with the particle size varies at 45 mu m, 75 mu m and 150 mu m and the mass was put to 1-10 grams with incremental dosing of 0.5 grams for every 20 minutes. Results of the study showed that hydrated lime, limestone and concrete waste with different sizes and mass were capable in achieving pH targets required for neutralisation of the AMD. Overall, metal concentrations of Fe, Al and Cu followed a certain reduction trends whilst Mn has shown a poor reduction.