Water, Sewage & Effluent September-October 2017 | Page 29

A ‘greener’ approach SewTreat managing director and spokesperson, Theunis Coetzer, adds that biological wastewater treatment is an accepted practice used worldwide. The process involves confining naturally occurring bacteria at a very high concentration in the treatment process, whether it is plastic type, containerised type, or civil constructed type. From here, this bacterium, together with some protozoa and other microbes (collectively referred to as activated sludge), are treated in an anaerobic and aerobic process. They are then returned to the anaerobic phase to eliminate sludge accumulation and waste generation. “In a nutshell, the bacteria digest all impurities and the wastewater is then cleansed. The treated wastewater or effluent can then be discharged to receiving waters — normally a river or the sea — or alternatively used for irrigation, flushing of toilets, or general non-potable uses,” he explains. “SewTreat has developed a highly effective multiple strain bacteria range that gets added to our plants; this specifically-bred bacteria feed on the complex substances in the wastewater, converting them into simpler substances, improving final effluent on a reduced footprint.” He notes that globally, the composition of effluents discharged to receiving waters is regulated by the national environment agencies. The legislation is concerned with the prevention of pollution, and therefore sets concentration limits on dissolved organic carbon (as BOD or COD), nitrogen, and phosphates, and other compounds that cause eutrophication in receiving waters. It also attempts to limit the discharge of known toxic Water Sewage & Effluent September/Oct ober 2017 27 to upgrade an existing plant to increase capacity and efficiency than undertake the expenses of a new plant.” technologies will make them high-tech, efficient, and sustainably safe,” he says. “On a smaller scale, based on the trickling filter technology, we have smaller plants that are built into containers, for use at a lodge, small rural communities, a golf course, or similar applications.” This is also ideal for into-Africa projects and Braybrooke assures that discharge standards are met, along with a short turnaround time. “It’s almost plug and play,” he says. The expert is adamant that all water types can be treated, from municipal water to ultra-pure water used in pharmaceutical applications and high- pressure boilers. There are a variety of water sources, each with their own technology with which to treat them, he says. “They can be treated on site and the plants do not have to be a greenfield expansion. More so with urbanisation and its increase in population within larger cities, municipalities should rather look Despite all the benefits to the economy of reused water, fear still exists around the various sources.