Underground-settlers

2014 CASE STUDY:

Water quality improved

By re-engineering underground settlers, which separate suspended solids from liquid, Sibanye has been able to improve the water quality of surface water discharges, originating from the underground mine water systems, into the environment.

The chemical dosing programmes of the underground settlers have been reviewed and automated to achieve a 70% reduction in the discharge of heavy metals from Cooke 1 and 2. The programme will, therefore, be rolled out at other Group operations throughout 2015.

Settlers have been working underground for the past 40 years to adjust pH and remove mining solids from mine service water, which is circulated in a closed loop. As such, the water is reused and only excess from the fissure water source is discharged into the environment under licence. The settlers protect underground pumps and piping infrastructure from chemical corrosion and mechanical attrition but they had never been able to improve water quality until now.

“This is a new way of thinking about underground water treatment,” says Jacques Cilliers, Engineering Manager: Water Systems for Sibanye. “Indirectly, it improves the quality of water discharged into the environment and could ultimately reduce the environmental liability.”