Thesis Archive
Evaluation of Treatment Efficiencies of Locally Available Neutralizing Agents in Passive Treatment of Acid Mine Drainage
Melchor, Bernadette
Singson, Giulio Miguel
Abstract:
The mining industry in Philippines is one of the contributors that make a significant impact on its economy, but the disposal of waste specifically, acid mine drainage (AMD), generated from this industry presents a serious problem to the environment. The emerging environmental and economic concerns generated by AMD disposal have led to the determination of other alternative neutralizing agents (NA) that can be used in the passive treatment of AMD. Establishing alternative NAs presents the benefit of decreased environmental footprint and the advantages of waste valorization. In past researches and experiments conducted, limestone had been established as an effective NA for AMD, but its poor performance in heavy metal removal led to the necessity of discovering other alternative, effective and efficient NAs. In this study, the researchers designed two batch experiments that determined the effectivity and efficiency of low-grade serpentinite (LGS), fly ash (FA) and concrete aggregates (CA) with comparison to limestone (LS). In first batch of experiment, varying water/rock ratio of 0.75, 1.00, 1.50 and 2.00 for each NA were assessed to determine the NA that were used for batch two experiment. After the first batch of experiment, CA displayed the most significant results in the process of AMD treatment as it was able to neutralize and raise the pH of AMD to 12.42 and removed 99.64% Fe, 99.69% Ni, 96.74% Al and 57.02% sulfate, which complied with the Department of Environment and Natural Resources (DENR) Class C water standards. Concrete aggregate was then used in the conduct of second batch of experiment. The grain sizes used were >4.75 mm, 4.75mm to 3.35 mm, and 3.35 mm to 2.00 mm. Results displayed that CA with 3.35 to 2.00 mm size range had the most efficient and effective capability in AMD treatment neutralizing the pH to 6.78 with 89.96% Fe, 71.91% Ni, 80% Al and 50% sulfate removal.
Adviser:
Orbecido, Aileen H.