Technology developed in Singapore by US firm, Evoqua, uses half the amount of electricity required by conventional seawater reverse osmosis the firm has claimed.
The technology emerged from a three-year pilot project started in 2010 at the PUB Variable Salinity Plant in Pasir Ris. PUB has told the Singapore press that it hopes to scale up the technology next year.
The power requirement using Evoqua technology is about 1.65kWh/m³ to 1.8kWh/m³. PUB hopes to further reduce the amount of energy needed for the process to just 1.5kWh/m³ of desalinated water. With conventional reverse osmosis method, 3.5kWh /m³ of electricity is typically needed.
The Evoqua technology removes salt ions by electrochemical desalination whereby they are attracted to electrodes of the opposite charge. This energy-efficient method makes desalination a more viable and sustainable alternative said PUB.
Singapore currently consumes 1,600 Ml/d of water a day. The demand could almost double by 2060. Up to 25%r of the current demand is met by desalinated seawater. PUB hopes desalination can continue to supply the same proportion even in the long term when demand goes up.