In the quest to mitigate water supply difficulties that have been prevalent in South Africa in the past few years, international engineering consultancy and technology provider Royal HaskoningDHV says innovative wastewater treatment and smart water solutions are relevant in the context.
“Energy savings, optimisation and efficiency are currently issues of concern in South Africa. Smart water technologies are exciting and relevant to what the country needs,” says Royal HaskoningDHV South Africa advisory group director Sheilla De Carvalho, naming the Nereda technology and Aquasuite as contenders to tackle South Africa’s current water challenges and issues.
The Nereda technology is an innovative biological wastewater treatment that purifies sewage using aerobic granular biomass.
“Contrary to conventional activated sludge technologies, the Nereda purifying bacteria concentrate naturally into compact aerobic granules. These granules are micro-reactors themselves, enabling all biological processes to take place in the granular biomass and do not require different physical compartments,” explains Royal HaskoningDHV water and wastewater process engineer Joana Doutor.
In addition, these granules are dense and therefore settle very fast. The granules allow for simultaneous biological removal of carbon, nitrogen and phosphorous compounds, making the operation chemical-free. Nereda is also a one-tank concept, which means that all processes happen in one reactor that works in batches/cycles.
Operational savings on Nereda are substantial with Doutor estimating that as much as 30% can be saved in energy costs. Moreover, owing to the technology’s smaller carbon footprint, capital savings in terms of the initial investment in the technology can be between 20% and 30%.
Currently, there are two fully operational Nereda plants in the Western Cape, with a third plant underway in Johannesburg. Doutor says that the third plant is a retrofit installation to help the existing wastewater treatment plant perform better.
Another smart water intelligent solution for the entire water chain, Aquasuite, comes in many different forms, each with different water sector requirements. It is easy to integrate on existing automated water and wastewater plants as well as water networks.
Mukwati explains Aquasuite to be a software platform for the water sector focused on reliable prediction of supply and demand supported by smart controls. She notes that, over time, with innovation and technological advances, the smart technology has evolved into real-time prediction.
For drinking water supply, Aquasuite forecasts the consumption for the upcoming 48 hours, based on the supply area’s demand patterns. Equipped with this real-time forecasting information, optimisation in the control of the volume and pressure in the entire water system can be achieved. A stable and efficient process performance, optimal water quality and minimal energy consumption was noted to be the result.
Mukwati further remarks that the water shortages the country has been experiencing are not only due to drought, commenting that a lot of water is lost due to pipe bursts and water leaks. Aquasuite can alert to deviations caused by pipe bursts.
Optimising water management is the focus of smart water solutions, and these solutions can help to mitigate the effects of the water crisis South Africa has been experiencing.
“It will also impact positively on clients, decreasing the need for big spend in terms of new build water infrastructure, optimising the use of the existing assets in the water network, ensuring water availability,” notes Mukwati.