• Project No 2016
  • Project Name Converting waste or solar heat to treated water using membrane distillation
  • Lead Organisation GWMWater
  • Research Lead Victoria University
  • Main Researcher Mikel Duke
  • Completion Year 2012

Project Description

The steam produced by boiling a kettle of salty water can be collected, condensed and drunk. Membrane distillation is an analogous process to this, but in this study the salty feedwater forms a salt-free vapour at a lower temperature; 30 – 40°C. The warm feedwater and vapour are pumped past a thin, porous membrane which repels liquid water but allows vapour to pass through the pores into a cold stream of freshwater on the other side. The vapour condenses and increases the volume of fresh, salt-free water. In this project an operational pilot plant was built and installed at an electricity generating station which produces waste heat and a stream of salty effluent that is normally discarded. The pilot plant was equipped with a 0.67m2 membrane, ran continuously for 3 months, and produced an average of 2.2L freshwater per hour. This equates to 3.4L/h/m2. The membrane area can be scaled up to increase production. It was concluded that this is a viable treatment technology for industrial wastewater that emits minimal greenhouse gasses.