Microfiltration followed by desalination through reverse osmosis
near Portland, New South Wales, Australia
Both 6 ML/d - Mt Piper & Wallerawang (upgradebale to 12 ML/d)
Challenge While 'blow down' water from cooling towers at NSW electricity generator Energy Australia's Mt Piper & Wallerawang power stations has been collected, the volume of salts retained during the cooling process has made it unsuitable for reuse without treatment. Previously this water was disposed of through licensed and controlled discharge to the environment with fresh water being continually drawn from local rivers and dams to meet on-going process requirements. At the time, the client (Delta Electricity) sought to optimise its water usage through reuse.
Solution In a joint venture with UGL, Osmoflo designed and commissioned two 6 MLD reverse osmosis plants to desalinate the collected blow down water and convert it to a quality suitable for reuse. Both plants were constructed in modular form to allow for increased capacity if required. Pre-treatment is microfiltration. As a result of the reverse osmosis process, salinity is reduced from more than 3,000 mg/l Total Dissolved Solids (TDS) to less than 50 mg/l at Mt Piper and less than 200 mg/l at Wallerawang for reuse in cooling towers. Through an operations and maintenance contract, both plants were constantly monitored from Osmoflo's 24 hour control centre at Burton SA. This utilised Osmoflo's proprietary PlantConnect software, which acts as a platform for all our O&M activities and ensures optimum plant performance while eliminating the need for full time operators on site.
Result Energy Australia's reliance on local water sources is now substantially reduced and discharges of blow down wastewater to the environment practically eliminated. We have also offered a complete plant monitoring and control solution to the client for over 10 years at the Mt Piper power station, offering reliability and complete support for the RO Plant.
Note: Mt Piper power station is now operated by Energy Australia, with Wallerawang power station being closed in 2015.
Energy Australia is an electricity generation, electricity and gas retailing private company in Australia. They have a portfolio of generating sites using thermal coal, natural gas, hydro-electric, solar energy and wind power.