A basic study for stabilization of heavy metal contaminated tailings by inorganic binders

무기고화제를 이용한 중금속 오염 광미의 안정화 처리를 위한 기초연구

Stabilization treatment is one of processes for wastes and their components to reduce their toxicity and migration rates to surroundings. Inorganic binders such as calcium hydroxide, blast furnace slag and red mud were tested for their potential applicability to in-situ stabilization of heavy metal contaminated tailings in the abandoned metal mines. Columns(150mm dia. ${\times}$ 450mm length) filled with mixtures of inorganic binders and tailing from the Geumjang mine with various mixing ratios of binders to tailings, 5%, 7% and 9% were applied artificial rainfall tests for 28 days. Effluents from columns filled with calcium hydroxide and tailing showed high pH's of ~12.5 and a increasing trend of concentration in Pb and Zn with a significant decrease in permeability in terms of elapsed days. Those with burning slag and tailing showed pH's of ~8.5 and significantly low concentrations in heavy metals with a stable permeability. In case of red mud, effluents showed significantly low concentrations in heavy metals but a decreased permeability with pH's of ~10.5. Conclusively, this basic study suggests burning furnace slag be a potential stabilizer for effective treatment of heavy metal contaminated mine tailings.