About CleanWorld
CleanWorld is the leading North American innovator in advanced, high-solids anaerobic digestion (HSAD) technology. Based in Sacramento, California, CleanWorld is a subsidiary of Synergex, a global leader in technology for more than 35 years.
CleanWorld was originally formed in January 2009 as Clean World Partners, LLC to respond to the confluence of technology readiness, consumer behavioral change, and federal and state regulatory mandates that require expanded diversion of waste from landfills, reduction in greenhouse gases, and increased production of renewable energy and transportation fuel.
Our History

Our UC Davis pilot digester project. Our first proving ground and ongoing research facility.
Founded in January 2009, CleanWorld Partners, LLC originally licensed five technology patents from the University of California, Davis. In January 2011, Synergex Ventures invested in the company, acquiring a controlling interest and assuming management responsibilities.
In May 2011, the company began upgrading the UC Davis Biogas Energy Pilot Plant, which had last been operational in 2009, installing new controls software, piping, and other improvements.

CleanWorld ARP Plant.
In March 2012, the company commissioned the first commercial high-solids anaerobic digester in the U.S.—a 4,000 ton per year (TPY) facility at American River Packaging in Sacramento, which provides 30% of the electricity for ARP’s operations.
On November 1, 2012, CleanWorld Partners, LLC was converted to CleanWorld, a California Corporation.
In January 2013, CleanWorld commissioned the 10,000 TPY Sacramento BioDigester, at the time the largest HSAD system in North America. At the end of that year, in December 2013, CleanWorld commissioned the 20,000 TPY UC Davis READ facility, diverting campus organic waste from landfills, while producing green electricity for the campus’ microgrid.
CleanWorld will complete a scale-up of the Sacramento BioDigester to 40,000 TPY in the first half of 2014. Once completed, the facility will produce 615,000 diesel gallon equivalents (DGE) annually of renewable natural gas for area truck fleets.
About Our Inventor, Dr. Ruihong Zhang
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Dr. Zhang being filmed at a recent CBS episode of The Car Czar, telling CleanWorld’s story. Click photo to watch story.
Ruihong Zhang is professor of biological and agricultural engineering at the University of California, Davis. Her research is focused on waste and wastewater treatment, bioenergy and bioprocessing engineering, and air quality control. She has twenty years of experience in the research and development of anaerobic digestion and other bioconversion technologies.
Dr. Zhang has traveled the world several times over and witnessed first hand the emergence of AD technology in a variety of configurations and applications. She has made it her mission to apply this technology in innovative ways to solve the world’s organic waste problems.
Recent Recognition Highlights

CleanWorld is excited to share this 2013 GEELA award with our partners!
CleanWorld shared the 2013 Governor’s Environmental and Economic Leadership Award, California’s highest environmental honor, with its partners, who enable CleanWorld to help communities achieve their zero organic waste initiatives through landfill diversion and farm-to-fork-to-fuel economies.
International Bioenergy Project of the Year Award: Renewable Energy World – Power Engineering Awards (PowerGen), Orlando, Florida, November 2013. Competing against a field of sixteen applicants representing bioenergy projects from four continents, CleanWorld received the highly sought-after International Bioenergy Project of the Year award for its Sacramento BioDigester facility.

Keith Leech, head of the fleet for the City of Sacramento went to New York to accept this award from Energy Vision on the team’s behalf!
2013 Energy Vision Leadership Award: Energy Vision’s Seventh Anniversary Celebration, New York, November 2013. Energy Vision, a national non-profit organization that promotes clean, renewable, petroleum-free transportation fuels, presented the City of Sacramento with this year’s Leadership Award. CleanWorld shared in the recognition as part of a pioneering partnership between the public and private sector, “making a true waste-to-fuel revolution in this country a reality.”
2013 Game Changer of the Year Award and 2013 Woman Innovator of the Year: (Michele Wong, CEO of CleanWorld), December 2013. At its 29th annual Regional Innovation Awards, Innovate North State awarded CleanWorld its Game Changer of the Year award. At the same time, Michele Wong, CleanWorld’s CEO, was awarded Woman Innovator of the Year. Innovate North State is committed to recognizing and supporting innovative businesses such as CleanWorld that are projected to create growth and jobs in Northern California.