Printed on: July 10, 2013

INL researcher finds new process to reuse industrial wastewater

By ALEX STUCKEY
astuckey@postregister.com

Aaron Wilson was reading some scientific articles to prepare for the Mountain West Water Institute about three years ago when a light bulb went on.

The same process used for extracting oil from vegetables, the Idaho National Laboratory researcher reasoned, probably could be used to treat industrial water.

His hypothesis proved correct.

That process, called Switchable Polarity Solvent Forward Osmosis, can make industrial water reusable, thereby reducing the need to draw more water from aquifers or other sources, Wilson said.

That makes it a great option for hydraulic fracturing, or "fracking," which uses 3 million to 5 million gallons of water in each well, he said.

Fracking is a process in which companies drill a well -- sometimes as deep as 10,000 feet below the surface -- and pump millions of gallons of water, sand and chemicals underground to break apart the rock and release natural gas.

"We already have a lot of industrial interest," Wilson said. "(Companies) are very excited."

Once funded and operational, the process will be able to fit on the back of a trailer.

"(A company) could take (the process) to a drilling platform and treat the water right there, (for example) reducing the amount of trucking you have (to do)," he said.

Currently, Wilson is working with a demonstration model, using food coloring to represent dirty, industrial water.

On one side of the demonstration pump sits a container of "wastewater," purple with food coloring. On the other side is a container of draw solution.

Wastewater is pumped through tubes past a semipermeable membrane, leaving the purple color behind. It comes out the other side, mixing with the draw solution.

The water and solution are heated until the solution separates from the water, like oil. It then is siphoned off the top, leaving cleaner water in the container. That water can be reused for fracking and other purposes, eliminating the need to dip into area water resources too many times.

The draw solution is what sets Wilson's method apart.

"Where (INL) saw the hole was in draw solution (technology)," INL Chemical Group Lead Fred Stewart said. "I had something I thought was really cool and then (Wilson) came up with his idea. Dang it, his is cooler than mine."

Although the process could be used in other industrial settings, Wilson said one reason fracking is a focus is because of funding possibilities.

"(People will) spend quite a bit of money so they are not polluting the environment," he said.

Wilson isn't sure when the process will be ready for commercial use, but said it could be ready to go in two years if funding comes through.

"We're already involved with industrial partners," he said. "I think we're in good shape on this, in terms of a time frame."

Idaho National Laboratory reporter Alex Stuckey can be reached at 542-6755.