Fresh water from salt water. This is likely a big deal.

SOSc

Sometimes you see something posted in the news, and you think, wow. This morning is one of the moments as far as I’m concerned. A team at Columbia has come up with a strikingly new way to desalinate water. It appears to be easily manageable and requires less energy than existing methods. From Columbia’s website:

TSSE utilizes a low-polarity solvent with temperature-dependent water solubility for the selective extraction of water over salt from saline feeds. Because it is membrane-less and not based on evaporation of water, it can sidestep the technical constraints that limit the more traditional methods. Importantly, TSSE is powered by low-grade heat (< 70 C) that is inexpensive and sometimes even free. In the study, TSSE removed up to 98.4% of the salt, which is comparable to reverse osmosis, the gold standard for seawater desalination. The findings also demonstrated high water recovery (>50%) for the hypersaline brines, also comparable to current seawater desalination operations. But, unlike TSSE, reverse osmosis cannot handle hypersaline brines.

“We think TSSE will be transformational for the water industry. It can displace the prevailing practice of costly distillation for desalination of high-salinity brines and tackle higher salinities that RO cannot handle,” Yip adds. “This will radically improve the sustainability in the treatment of produced water, inland desalination concentrate, landfill leachate, and other hypersaline streams of emerging importance. We can eliminate the pollution problems from these brines and create cleaner, more useable water for our planet.”

Yip’s TSSE approach has a clear path to commercialization. The heat input can be sustainably supplied by low-grade thermal sources such as industrial waste heat, shallow-well geothermal, and low-concentration solar collectors. He is now working on further refining how TSSE works as a desalination method so that he can engineer further improvements in performance and test it with real-world samples in the field.

The most exciting part for me is the “clear path to commercialization”. For coastal cities, or for places where the water supply is threatened, the ability to purify water that has been polluted through industrial use is a huge deal. Having lived in Arizona desert and seen how urban growth and agricultural were limited, to get clean, pure water from waste would total recast the issues. This would be a big deal in the developing world as well – especially in coastal mega-cities.

Watch this space as they say!

The Author

Episcopal bishop, dad, astronomer, erstwhile dancer...