Malmesbury Wastewater Treatment Works, South Africa
Due to sustained growth in the town of Malmesbury, the wastewater treatment works, which treats both domestic and industrial wastewater, is being upgraded to a 10 megalitre per day membrane bioreactor (MBR) plant.
Aurecon came up with an innovative approach - to decommission the old biofilter plant and incorporate the old activated sludge plant into the MBR as a hybrid system. This has reduced the overall cost of the upgrade through maximising use of existing infrastructure and reducing peak wet weather loading on the membranes. The plant is designed for nitrification-denitrification-biological excess phosphorus removal.
The control and instrumentation systems are being modernised and most of the treated water will be reused in non-potable applications. Other notable components of the upgrade include a new inlet works incorporating fine screening for the MBR component, aerobic digestion, mechanical sludge dewatering, chlorination and irrigation systems, as well as a new administration and control building overlooking the new plant.