When Bacteria Give Waste Their Best Shot

Today’s new green jobs are taking a tip from nature with its accumulated 3.85 billion years of research and development experience. In nature nothing is wasted. Anaerobic Phased Solids (APS) are being faithful mimics taking a waste stream and converting it to biogas and soil fertilizer amendments. San Joaquin valley, the nation’s garden, is giving a series look at APS technologies as a way to recycle their own waste stream and to produce energy sources right in the fields. Let me break this down. University of California at Davis developed and pioneered an APS technology that is being tested commercially. The process is based on the work of Dr. Ruihong Zang, Professor at the Department of Biological and Agricultural Engineering and director for the UC Davis Biogas Energy Project. While other APS processors can convert waste material, Dr. Zang’s process is more efficient and received an award from the Environmental Protection Agency in 2007. Basically, the process uses bacteria to break down waste, much as we humans do in our digestive systems. But instead of feeding materials into one digestion tank, the process happens in two staged environments, which allows for different bacteria types to give solid and liquid waste with their best shot. A first group of ordinary bacteria breaks down waste in about 10 to 12 days to produce water and organic acids. This includes food processing waste, municipal green waste like grass, agricultural crop residues, animal rendering and animal manure. The resulting liquid is then pumped into holding tanks that are maintained at 130 Fahrenheit degrees with a neutral pH to encourage a second bacterial group to reduce the soup to 65 to 70 percent methane gas, in addition to biohydrogen. Both can be used to produce biofuels. The process takes potentially harmful methane gas that is produced at land fill sites and recycles it as biofuel. The benefit of this two-staged process is that it can process up to 30 percent of waste. Previous APS technologies typically could only handle a 5 percent solid waste stream. The APS process pioneered at UC Davis and has been licensed by different partners including Onsite Power Systems to bring the technology to commercial uses. Warren Smith, Chief Executive Officer of Clean World Partners, LLC, was instrumental in securing the land for Raley Field in West Sacramento, which is now home of the Sacramento River Cats. He understands how to build private and public partnerships. For a short time, Smith served as president of Onsite Power Systems before his involvement with Clean World that develops, designs, builds, and manages turnkey anaerobic digestion systems. “In the past we thought about getting ride of waste, putting it in a hole and covering it up. The approach has become a major problem,” he said at Clean Partner’s offices in Sacramento. Smith cited AB 939, California’s Integrated Waste Management Act of 1989 that created the California Integrated Waste Management Board, and required local governments to meet tougher solid waste diversion goals of 50 percent by 2000. Sacramento further expanded government mandates with the passage of AB 32 in 2006 making the Air Resources Board responsible for aggressively reducing green house gas emissions by 2020. Increasing the number of landfill sites is no longer an option, said Smith. “APS is the only technology written into the scoping plan of AB 32 as waste conversion,” he said. Clean World Partners has proposed a Sacramento BioRefinery #1 at Folsom Prison which produces, he said, “a pound and ½ of waste per person per day.” The proposed facility will produce 400.000 cubic feet of renewable gas per day. The proposal needs to make it through an EIR (Environment Impact Report) scheduled for next year. “Supply plus demand equals the truth,” said Smith. He understands that truth to reside in renewable energy sources. You can email Warren Smith for questions. Lenore Weiss http://techtabletalk.posterous.com/