What if you could save fresh water by mixing power-plant wastewater with fracing wastewater? West Virginia University researchers may have found a way to do just that.
In the U.S., the power industry is second to agriculture in the amount of water it uses. And it uses a lot of it in thermoelectric-plant heat exchangers. At some point, some water will evaporate and salts will reach concentrations rendering this blowback water unusable in the cooling system. For it to be reintroduced into the system, treatment is needed.
With fracing comes wastewater, called produced water. It’s estimated that a single well will produce maybe 500,000 to 1 million gallons. In 2013, the DOE had the number of hydraulically fractured oil and gas wells at about 2 million.
Untreated produced water contains substances like magnesium, strontium and calcium, that would damage cooling towers. But mix frac and blowback waters, and the harmful chemicals settle out. The water can now be re-used with the added benefit that a byproduct— chlorine—disinfects the cooling system
“The beauty of this approach is you solve two problems with one integrated solution,” said Lance Lin, a civil and environmental engineering professor and principal investigator on the project.
The researchers must figure out the mixing ratios. They are also looking for other treatment methods to clean the wastewater.
The project is funded by a $400,000 Department of Energy grant.