Canadian desalination innovation uses evaporation for energy

Two graduates from the Simon Fraser University in Vancouver, Canada, have developed an innovative solar process for desalinating seawater. Their start-up company, Saltworks Technologies Inc, claims that the process can reduce electricity requirements by up to 80% and has the potential to cut the cost of desalinated water in half.

Sparrow is a professional engineer and inventor of the process. Zoshi is a project manager with an electrical engineering background. Their patent-pending technology has been proof-tested by Powertech Labs Inc, a subsidiary of BC Hydro.

The pair recently won the BC Hydro $60,000 First-prize package, the British Columbia Innovation Council’s $100,000 Proof-of-Concept prize and the $20,000 BC Hydro Sustainability prize and will use the funds to grow the company and commence work on a mobile demonstration plant.

“Our technology can desalinate seawater to potable standards using solar energy and dramatically reduces input electricity requirements,” says Sparrow, Saltworks’ CEO. A key point, he notes, is that they can build desalination plants using commercially available components, saving both money and time.

Saltworks’ patent-pending process employs an innovative thermo-ionic energy conversion system. The energy reduction is achieved by harnessing low-temperature heat and atmospheric dryness to overcome the desalination energy barrier. The system works best in the dry regions that need water.

A concentrated saline solution, which has concentration-gradient energy, is fed into Saltworks’ proprietary desalting device to desalinate either seawater or brackish water. Some electrical energy is used to circulate fluids at a low pressure, yet the bulk of the energy input is obtained through the evaporation of salt water.

An outfitted 1,000 L/d seawater pilot plant, complete with chemical-free pretreatment, will soon be fully operational at a harbour location in Vancouver. The public release of Saltworks is timed to coincide with a presentation at the International Desalination Association’s World Congress in Dubai during 7-12 November 2009.