ANTIOCH -- Delta Diablo Sanitation District is expanding its efforts to find ways to not waste wastewater, but instead create renewable energy.
Since early this year, Stanford University researchers have worked with chemists at Delta Diablo's Antioch plant on a small-scale demonstration project that converts nitrogen found in wastewater into nitrous oxide gas through combustion with already collected methane gas. The reaction can create a powerful fuel source.
The district and Stanford's Woods Institute for the Environment announced this week they will expand the work on that project, called Coupled Aerobic-anoxic Nitrous Decomposition Operation, or CANDO, to a pilot demonstration. The pilot would be about a hundredth the size of a full-blown application.
"With the pilot, we hope to prove this technology works at a realistic and believable scale," said Yaniv Scherson, a Stanford postdoctoral scholar and the project team leader.
Delta Diablo laboratory manager Darrell Cain adds: "We want to see if there's convincing evidence that it works in our world, can be practically applied and is cost-effective."
The Stanford Nitrogen Group started working on the idea in the lab in Palo Alto in 2009 using synthetic wastewater, or tap water with added chemicals and nutrients. Bacteria are used to convert the nitrogen of the wastewater, which is found as ammonia, into the gas.
Scherson said the process applies the same principles he used fueling rockets while working in aeronautics, while Cain describes it as creating a fuel source similar to that used to turbo-boost cars as seen in the movie "The Fast and the Furious."
The experiment showed success at the lab, which led the researchers to seek a real-life location to expand the work.
After soliciting several Bay Area sites to no avail, they found Delta Diablo to be a willing partner, Scherson said.
"They were highly supportive of what we're trying to do, and motivated, so really it has been a great partnership," he said.
Delta Diablo has actively been looking for ways to use alternative energy sources such as wind and solar, along with byproducts from collected wastewater, mainly methane, to cover increasing energy costs while reducing its reliance on the state's power grid.
"We have a general manager and a board that is progressive and willing to look at new ideas, especially to offset costs and ultimately benefit taxpayers," Cain said.
Looking into the new ideas is also energizing to staff, Cain said. All told, the district's three chemists and intern put in the equivalent of a quarter of a full-time position monitoring the project, he said.
Reducing nitrogen discharge can also help the district stay ahead of anticipated future state regulations for emissions, while also chipping away at a growing pollution problem in waterways throughout the world. Waste nitrogen sucks all the oxygen out of the water, creating "dead zones" that threaten fish and marine wildlife.
Researchers from Lawrence Livermore Laboratory and Miami-based Chemergy started using the plant recently to study a technology that converts wet biosolids into hydrogen gas to produce electricity.
Delta Diablo also plans to launch a study late next year that looks at converting products from used cooking grease into energy, district officials said.
The Stanford project is supported by grant funding from the university's TomKat Center for Sustainable Energy, the National Science Foundation Engineering Research Center and Veolia Water.
Experimentation is set to begin early next year, as design work is completed and the large pieces of hardware are ordered, district officials said.
The experiment will run continuously for about six to nine months, Scherson said.
Contact Paul Burgarino at 925-779-7164. Follow him at Twitter.com/paulburgarino.