In what is considered the company’s flagship plant, WEC Projects, in a joint venture with a local construction, concessions, and manufacturing group, has designed and built a water treatment plant which will supply potable water to one of the most populous communities in Gauteng.
The R270 million plant has been designed to provide 60 Ml/day and was commissioned as part of a R1 billion upgrade project for the community which has experienced a considerable increase in demand for potable water over the last few years. The scope of work for WEC Projects included the mechanical, electrical, and instrumentation work. WEC Projects, with a joint venture partner, was awarded the contract to expand the existing facility in 2016, including the mechanical, electrical, and control scope of the project. However, due to the complexity of the project and the need for buy-in from the local communities benefiting from the treatment plant, final commissioning only took place in 2021. The raw water is drawn from a nearby dam and pumped to the facility where it initially undergoes clarification to remove suspended solids. After the primary clarification process the water undergoes dissolved air flotation to remove any remaining solids and oils. The clarified water then enters a rapid gravity sand filtration system to remove particles.This type of filtration system was specified due to the higher filtration rate it provides compared to conventional sand filters, a necessity for a plant that is required to supply more than 500 000 people.
After exiting the sand filter, the water is pumped to the ozonation facility for rapid oxidation and disinfection. It then undergoes a second filtration process, this time through a filter system containing granular activated carbon. This process removes organic chemicals and other similar impurities. The final process sees the chlorification of the water to ensure that any harmful impurities such as bacteria are removed. Says Wayne Taljaard, Managing Director of WEC Projects, “This project certainly rates as one of the most challenging that we have undertaken. The design of the plant required the water to undergo a complex processing solution in order to achieve the quality level required by the local municipality. We were also required to integrate the new plant module into the existing treatment plant. As a result, the plant integrates a sophisticated and advanced control and instrumentation system to ensure consistent quality and plant uptime.” Adds Taljaard, “While the requirements were for a water treatment plant capable of delivering 60Ml/day, the new plant has been tested successfully to 120Ml/day, ensuring that it will be able to handle increased demands well into the future.”