Two research streams at the University of Nevada, Reno (UNR), USA, have come together to create a new solar-powered membrane distillation desalination configuration.
The US Patent Office recently issued a patent for a direct-contact membrane distillation (DCMD) process developed by Dr Tzahi Cath (Colorado School of Mines) and Drs Amy E Childress and V Dean Adams (UNR).
At the same time, Francisco Suarez, a doctoral student in hydrological sciences at the University, has been developing an artificial salt-gradient stratification process that traps solar heat at the bottom of solar ponds and uses the collected energy to power the membrane distillation system.
The process has been highly successful in the lab in a small-scale experiment using a 400 gallon (1,500 L) tank, where dissolved solids and precise fiber-optic temperature sensing are being used to track the process as it desalinates the water. The next step for the research group is to build a pilot-project, demonstration-scale, low-temperature desalination system in an open environment.
The distributed temperature sensing system, which uses a laser and fiber-optic cable to record temperatures in the solar pond has been developed by Professor Scott Tyler of the Department of Geological Sciences & Engineering.
A longer article on this research will appear in the February/March issue of Desalination & Water Reuse.