- Project No 1025
- Project Name Capacitive deionisation for high recovery and low energy desalination of brackish water supplies
- Lead Organisation SA Water
- Research Lead University of South Australia
- Main Researcher Linda Zou
- Completion Year 2010
Remote and regional Australian communities commonly produce potable water by removing salt from brackish groundwater. Existing desalination technologies, such as reverse osmosis (RO) have high electrical energy and technical requirements. Groundwaters often contain high levels of silica (quartz) which, together with the salts, form scale which blocks RO membrane and other components which are expensive to replace. This research examined an alternative desalination process: capacitive deionisation. Laboratory-scale experiments found that single-walled carbon nanotubes were the best material to use for electrodes, that membranes placed before the electrodes increased efficiency of salt removal and decreased energy usage, while silica, which lacks a charge that would bind it to either the positive or negative electrode, did not form scale deposits nor interfere with the desalination process. A full-scale version of this unit was tested onsite in the Northern Territory and described in WaterRA Project 1047.