Remediation of Heavy Metals by using Industrial Waste by Products in Acid Mine Drainage

Abstract

Acid Mine Drainage (AMD) is one of the main important problems being combated today. Laboratory tank experiments were conducted to evaluate the use of industry waste to adsorb and control the mobilization of metals from contaminated acid mine water. The main physical conditions such as pH and treatment performance are displayed. The solution of acid mine were sampled from the sites and their concentrations of heavy metals were determined. Three types of industrial waste were used as low-cost adsorbent materials in the treatment process which are Ladle Furnace Slag (LFS), Fly Ash (FA) and Biomass Ash (BA). The materials were described by X-Ray Diffraction (XRD), FESEM images and X-Ray Fluorescence (XRF). A comparative study between the removal efficiencies of heavy metals were evaluated. The results showed that about 78 to 99% removal efficiencies of metals were achieved from FA tank, 88 to 99% for LFS tank and 86 to 99% for BA tank. Tank experiment displays huge range of pH changes from acidity to nearly neutral phases when adsorbent was in contact with AMD. Remediation of AMD by using FA showed pH changes from pH 2.12 to 7.09, pH 7.3 for LFS and pH 6.8 for BA within 50 days of operation. From the removal rate, it is found that FA, LFS and BA have different efficiencies of heavy metal removing. The removal of heavy metals by using FA are more efficient to remove Fe, Mn, Cu, Ni and Zn. Meanwhile, LFS sample displayed as an effective adsorbent for treat Pb and Cd in acid mine drainage. The industrial waste used in this study increased and neutralized the pH to control AMD and improve water quality.