Advanced Water Treatment Process
Transfer raw water from wastewater treatment plants at Gibson Island, Luggage Point, Oxley,Wacol, Goodna and Bundamba via a network of pipelines. The treatment plants remove a significant amount of impurities and micro-pollutants.Pre-treatment involves coagulation, flocculation and the removal of bacteria and phosphorus.
Microfiltration involves passing wastewater through very fine hollow fibre membranes 0.04 to 0.1 micrometres in size (human hair ranges in size from 20 to 200 micrometres in diameter) that remove particulate matter, protozoa and some viruses. After passing through the membrane, the filtered water mostly contains dissolved salt and organic molecules.
Reverse osmosis involves forcing filtered water through a special membrane at high pressure to remove impurities such as dissolved salts, viruses, pesticides and most organic compounds.The membrane acts like an artificial kidney. Reverse osmosis produces water of a higher level of purity than drinking water. It is the same process used to desalinate seawater.
A look inside a reverse osmosis membrane – the heart of the water purification process
Advanced oxidation exposes the water to ultraviolet light combined with hydrogen peroxide to sterilise and eliminate remaining organic compound traces. The UV intensity is around 300 times that of the sun’s rays.
Stabilisation prevents corrosion of piping and pumping equipment, involving the addition of lime and carbon dioxide to return the water to its original levels of hardness and alkalinity. Disinfection involves adding chlorine to prevent biological growth in water pipes and storage tanks.
Purified water is ready for use by industry, agriculture and adding to the drinking water supply, if needed. Blending purified water with reservoir water is called indirect potable use.
The nutrient concentrate generated during the advanced water treatment process is treated to remove phosphorus and nitrogen before being discharged into the Brisbane River and Moreton Bay. As a further benefit to us and our environment, the discharge from our plants releases much lower nutrient levels into the environment than current discharges from existing wastewater treatment plants.