When environmental engineer David Drew read about an amazing new method of removing salt from seawater, he embarked on a search for research institutions to collaborate with on this kind of technology.
He didn’t have to
go very far to find one.
Zhen “Jason” He,
an assistant professor of engineering at the University of Wisconsin–Milwaukee
(UWM), was working on just such a project only a few miles from the Cedarburg, Wis., office of Gannett
Fleming Inc., the international engineering consulting firm Drew works for. He
is improving a microbial fuel cell that generates electricity using wastewater,
while also purifying the water. But after talking with Drew, He modified it,
adding a third capability – desalinating a separate supply of water.
It’s important to
a company like Gannett Fleming, which designs and builds water and wastewater
treatment plants. And the cost of energy, says Drew, is the reason desalination
is so expensive. In fact, says He, the energy from their microbial desalination
cell (MDC) can drive its own desalination process. “It won’t do the job
entirely, but it can act as an energy-saving pretreatment for saltwater,” says
He. “That would greatly improve efficiency while holding down costs.” The two
organizations are now working jointly to develop an MDC and bring it to market.
contains energy waiting to be harnessed,” says Drew. “So the water and the
energy are both addressed with this research.” He’s lab members are increasing
the size and scope of the prototype they began with, which was small enough to
fit in the palm of the hand and could only process 60 milliliters of wastewater
at a time.
“Dr. He’s lab was
the only one that had a good solution for scaling up the operation,” says Drew.
“That it gives you the necessary energy recovery while also the sustainability
of recycling the wastewater. We did a fair amount of due diligence to determine
where best to put our investment.”
itself is a three-chambered device in which microbes feed on the organics in
the wastewater of one chamber, causing removal of ions from saltwater in an
adjacent chamber. The metabolic energy created by the microbes also is the
catalyst that produces the current.
The next step,
and Phase I of the partnership, will be to produce an even larger reactor. If
the first year goes well, the partners have the option of continuing with a
Phase II, in which they will test the reactor’s commercial viability. “We want
to put it on the fast track,” says He. “We don’t want it to stay in the lab for
another five years.”
Water Technology Partnership
April 16, 2010