Estimation of Evaporation from Saline Tailings Dams

摘要

In the arid regions of Australia, fine-grained slurried wastes produced during mining are typically disposed of in large storages using sub-aerial deposition. Ore processing is conducted using groundwater that can have salinities that approach solution saturation. Precipitation of salts on the tailings surfaces during evaporation leads to the development of thin salt crusts that can significantly reduce the rate of evaporation. Quantification of the actual rate of evaporation from the drying tailings surfaces is important for assessing disposal strategies. Different methods of estimating evaporation were employed at mine sites in Western Australia to provide more information on the drying behaviour of saline tailings. The techniques used are described and typical results from a saline tailings storage are presented.