The use of quicklime in acid mine drainage treatment

Abstract

In this study, quick lime or calcium oxide (CaO) is used to treat acid mine drainage (AMD). Quick lime was obtained from quarry in Simpang Pulai, Ipoh, Perak. Quick lime is produced by calcination process of limestone at a temperature around of 900 °C to 950 °C. Acid mine drainage (AMD) was collected from a tin tailing pond that located in Perak. Jar test method was used to study the effectiveness of quick lime in AMD treatment. There are five parameters of weights and six interval times used in the experiments. The weights of quick lime used in this study were 1 g, 1.5 g, 2.0 g, 2.5 g and 3 g. The interval times used were 10 min, 20 min, 30 min, 40 min, 50 min and 60 min. For each experiment, 1 L water sample was poured into a 2 L beaker and quick lime was added into the water sample. Mechanical stirrer with speed 700 rpm was used in all the experiments. The quick lime before and after treatment were analysed by using carbon and sulphur analyser for sulphur percentage. From the results of the jar test, quick lime is found to be capable to increase the pH value and decrease the amount of heavy metals such as arsenic, cadmium, chromium in AMD.