ABC Environment ...Welcome to the future of wastewater treatment as Lundquist sees it. Current methods of wastewater treatment are costly and energy-intensive, so Lundquist believes that by using algae to treat wastewater, treatment plants could save on costs, reduce greenhouse gas emissions and recover key nutrients for reuse.
As a by-product, he says, the algae could be used to produce biofuels, a move that could see wastewater treatment plants go from energy consumers to net energy producers.
"You can use less electricity, you can recycle the water, the nitrogen and the phosphorus, you can keep mixing the algae into a fuel, and it keeps rolling on in an endless cycle," Lundquist says.
The key to treating wastewater with algae is raceways, small-scale artificial rivers consisting of a shallow network of looping ponds through which wastewater is passed. A paddlewheel gently pushes the water around the course, mixing the algae in as it goes.
The raceway design maximises exposure of algae to sunlight and fresh air, accelerating growth.
Lundquist has been engineering raceways for more than two decades. He says they are cheap to build and operate, yet they are highly efficient at treating wastewater. And the algal biomass produced is large enough to make the generation of biofuels viable.
Producing biofuels from algae is not a new concept, nor is using them for treating wastewater. But the idea of combining wastewater treatment with fuel production could be just the thing to remove the price barrier that has so far prevented the algal fuels industry from getting off the ground.
"People have been trying to produce biofuels from algae since the 1940s, but the problem remains that the cost is much too high," says Professor Michael Borowitzka from the Murdoch University Algae R&D Centre.
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