Traditionally acid mine water is neutralised with lime. Limestone is a cheaper alternative for such applications. A case study showed that limestone can be used effectively to replace lime for the neutralization of arsenic rich acid water. The cost of limestone treatment is 45.8% less than that of lime. The acidity can be removed from 33.5 to 0.06 g/L (as CaCO3). The study also showed no significant differences in the TCLP characteristics of the resultant sludge when water is treated with lime or with limestone. Sludge from the limestone treatment process can be disposed of on a non-hazardous landfill site
Reference:
De Beer, M., Mathews E.H., Krueger, D., Maree, J., Mbhele, F.N., Phalanndwa, M. and Novhe, N.O. 2008. Limestone neutralisation of arsenic-rich effluent from a gold mine. Mine Water and the Environment, vol 27(1), pp 1-10
De Beer, M., Mathews, E., Krueger, D., Maree, J., Mbhele, F., Phalanndwa, M., & Novhe, N. (2008). Limestone neutralisation of arsenic-rich effluent from a gold mine. http://hdl.handle.net/10204/3272
De Beer, Morris, EH Mathews, D Krueger, J Maree, FN Mbhele, M Phalanndwa, and NO Novhe "Limestone neutralisation of arsenic-rich effluent from a gold mine." (2008) http://hdl.handle.net/10204/3272
De Beer M, Mathews E, Krueger D, Maree J, Mbhele F, Phalanndwa M, et al. Limestone neutralisation of arsenic-rich effluent from a gold mine. 2008; http://hdl.handle.net/10204/3272.
