Fine Coal Dense-medium Cyclone Tests Conducted at Leeuwpan Coal Mine

Dolerite intrusion mechanisms and their metamorphic effect on coal were examined across four collieries in the south eastern Witbank Coalfield. In decreasing order of importance, intrusions cut safety by raising the risk of roof, pillar and floor failure, raise mining costs, reduce saleable tonnage, and increase waste generation and environmental risk.

Ants, termites, dung beetles and earthworms are known to improve soil health, but none had been deliberately applied as part of a mine reclamation strategy. Experimental and field scale studies asked whether dung beetles maintain their burial activity, and the soil services that follow, in soils typical of rehabilitated mine land, and set out recommendations for using them alongside existing methods.

Sets out good practice for planning, implementing, monitoring and adaptively managing land rehabilitation at surface coal mines, with generic rehabilitation objectives, implementation actions and suggested relinquishment criteria for each component. It updates guidance first issued in 1981 and revised in 2007, reflecting later changes to South African rehabilitation legislation.

Ion exchange treatment of acid mine drainage from a closed KwaZulu-Natal colliery was piloted and shown to give effluent free processing, converting the salts into saleable products rather than sludge and brine. Reverse osmosis had previously produced water of discharge standard but left both. Combined flow from the two mine compartments averaged 4.6 megalitres a day.