Growing populations and rapid urbanisation are increasingly adding pressure to the country’s already constrained wastewater treatment works.
With residential developments encroaching ever closer on wastewater treatment works and water demand rapidly growing, QFS has proven solutions that can lift the burden on both the plants and those people affected.
The reuse of wastewater has been a solution in water-scarce areas for decades, and are proving all the more viable with new technology developments. Here, QFS has many reference projects that prove its ability to deliver safe and sustainable water reuse solutions to the public.
The most notable is South Africa’s first-ever water reuse facility in Beaufort West, which produces 2.3 MLD of SANS Class 1 standard drinking water. The plant is configured with Memcor® ultrafiltration membranes to remove all total suspended solids, and a two-stage reverse osmosis plant to remove other smaller impurities and toxicants from the water. Finally, to ensure that the water is safe for human consumption, the water is treated with ultraviolet light and hydrogen peroxide – a step known as advanced oxidation. With this technology, this water-sparse Karoo town is able to augment its water supply for generations to come.
Similarly, QFS has designed, engineered, manufactured, installed and commissioned a 1.5 MLD reuse plant at De Doorns in the Cape Winelands to help save water. Secondary municipal wastewater is treated to produce irrigation water for the local farmers, helping to free up source water for the rapidly growing De Doorns community. The process uses ultrafiltration, ultraviolet disinfection and a granular activated carbon. The plant was completed in 2017.
The Ballito community in KwaZulu-Natal has also received a reuse solution from QFS after drought resulted in a shortage of drinking water. Using ultrafiltration and reverse osmosis, QFS designed, engineered, manufactured, installed and commissioned a 5 MLD plant, providing drinking water to the community and alleviating the drought stress.
Compact wastewater treatment
Available land is becoming a rarer commodity, which we can ill-afford to lose to conventional wastewater treatment plants. QFS, with its partner Evoqua®, can provide internationally proven wastewater technology on a much smaller scale.
Called a membrane bioreactor (MBR) system, MemPulse® MBR and Xpress® MBR are unique wastewater treatment processes that combine an activated sludge biological treatment process with an innovative membrane filtration system.
MBR eliminates the need for large clarifiers and sand filters, improves effluent water quality (ideal for reuse applications), allows for plant expansions in the same footprint, and uses a smaller biological process.
Another important aspect in any wastewater treatment plant is odours control. Hydrogen sulfide (H2S) becomes a major safety concern, not only for the personnel operating the works, but also the residents who live adjacent to these facilities because of a growing population.
Typically, H2S concentrations measured at inlet works are around 300 ppm, which can cause severe discomfort and necessitate additional medical care and treatment for personnel affected. This could lead to minimised personnel on-site, which would mean fewer operators to maintain and operate equipment. This can ultimately lead to strain on the plant and, therefore, strain on metros and communities, as sewage cannot be treated effectively.
By implementing odour control measures such as the I-BOx, these safety concerns can be effectively mitigated, ultimately improving worker safety and the functioning of wastewater treatment plants.
As part of the Reeston Wastewater Treatment Works in East London, QFS was responsible for the fast delivery and implementation of an I-BOx® 7010 odour control unit. The unit was installed for the inlet works section of the plant, as these areas are highly prone to H2S generation due to the turbulence created through various process units of the wastewater plant. The turbulent water allows the gases contained within the water to be released as the water follows its course though the inlet works.
The H2S released in these works is now no longer a safety concern for the roughly 80 personnel operating at the plant.