The Collection, Treatment and Utilization of Water Accumulated in the Coal Mines Located in the Upper Olifants River Catchment

A digital wetland map and linked database were compiled for the Upper Olifants River Catchment from existing literature, existing wetland layers and aerial photography. Wetlands cover about 2 147 km2, some 14 per cent of the 15 158 km2 catchment. The wetland layer is about 70 per cent accurate and its attributes about 60 per cent, so it suits baseline screening rather than site assessment.

A rating and ranking system was applied to South African coalfields and, separately, to the coal bearing countries elsewhere in the Southern African Development Community. The Waterberg ranked highest in South Africa and is the coalfield most worth detailed investigation as Witbank output declines. Botswana ranked highest among the other member states on contained resources and exploitation potential.

Co-treating coal discards with sewage sludge by hydrothermal carbonisation gave hydrochars with better physicochemical properties than treating either waste alone. The blended hydrochar reached a surface area of 20.35 m2/g and a pore volume of 0.38 cm3/g, and removed 97.19% of nevirapine and 93.32% of lamivudine from recycled water. Routes to activated carbon and hydrogen storage were also assessed.