With the Department of Water Affairs’ National Water Week Awareness campaign – taking place from March 17 to 23 – celebrating 20 years of water delivery for social and economic development, water treatment specialist Proxa is looking to the future of water in South Africa by developing cost-effective, sustainable solutions for treating industrial effluent streams and extracting value from them.
“Water security is a concern in respect not only of human consumption and ensuring ongoing industrial production processes but also . . . the multiple levels of impact that the future cost of water will have on South Africa,” says Proxa director of business development Elspeth Grahn.
Proxa has, thus, focused on developing solutions that will assist clients in optimising their existing processes and making them more economically efficient by producing zero waste, she adds.
Grahn notes that the company has seen a marked uptick in demand for water reuse solutions in the past five years, with Proxa’s international business experiencing “tremendous” growth that has driven the opening of six international offices.
She also points out that authorities and industries in South Africa have taken a more proactive approach in working together to reduce their water footprint and recover, recycle and reuse liquid waste streams. However, regulatory inertia is hampering the implementation of innovations that can improve water availability through more effective processes, she highlights.
“Water is a finite and irreplaceable resource that is fundamental to all forms of life. As the population grows, there is an ever-increasing demand for water. This is coupled with increased contamination of water as the industrial, manufacturing, power and mining sectors expand. The management and treatment of liquid waste streams is, therefore, critical in ensuring sustainable development in the country.”
Grahn stresses that this point is brought into even sharper focus considering the recent drought conditions in the country and the long-term underinvestment by government in water infrastructure. “However, we are seeing growing appreciation among the public and private sectors for better water management, triggering the development of strategies for the recovery and reuse of liquid waste.
Proxa has been at the forefront of water-saving developments, having implemented water management solutions in the mining, energy, pulp and paper, steel and, most recently, the food and beverage sectors.
Last year, the company developed effluent treatment solutions for food and beverage company Nestlé; global Western Cape-based wine producer Rupert and Rothschild; and beverage manufacturer AB InBev. These solutions have enabled them to achieve and, in some cases, exceed, global water footprint benchmarks.
Grahn notes that the chief objectives in these cases were to reduce the overall water footprint of the operation, secure a water source, ensure the quality of recycled water for reuse in the plant’s processes, reduce the net intake of fresh water and protect the environment using safe discharge methods.
“These sectors are showing significant growth and, in the last twelve months, Proxa has . . . increased water availability in the food sector by 15 000 m3/d. Water is being reused for applications such as cooling towers, boilers and wash water, and for agricultural applications such as irrigation and for animal use. Considering the scarcity of water, this is a significant opportunity for the country.”
Proxa completed the installation of a wastewater treatment plant for Nestlé in just three months, using a process that combines equalisation and dissolved air flotation to reduce the company’s water footprint and, subsequently, its water tariffs. Grahn says it was key to ensure that the design catered for a variable flow rate and variable effluent loading.
Further, the company unlocked a waste-to-value opportunity for Rupert and Rothschild using bioengineering and separation technology to develop a custom-engineered system, which produces irrigation-quality water and a composting by-product for reuse as vineyard soil conditioner from cellar effluent.
Proxa has also been contracted by Anheuser Busch InBev’s Ibhayi Brewery in Port Elizabeth to operate and manage its on-site effluent treatment process on an ongoing basis. The process comprises clarification, biological filtration, ultrafiltration and reverse osmosis. Proxa ROpack units further enhance the process to produce high-quality boiler feed water from treated effluent, thus reducing fresh-water intake at the operation.
Grahn highlights that each of these units has a compact design, with minimal operator intervention. Proxa also provides its clients with technical service contracts that cover the ongoing optimisation, technical support, operation and maintenance of the units.