Los Angeles County Producing RNG For Vehicle Fuel

(BioCycle Magazine) ... The (Los Angeles County) Sanitation Districts recently started up its biogas purification system, supplied by Unison Solutions and designed and installed by TetraTech. “With this new biogas purification system, we now produce renewable natural gas (RNG) that is used to fuel vehicles like cars, buses and trucks,” noted Robert C. Ferrante, Chief Engineer and General Manager for the Sanitation Districts. “We know that many cities [in California] are grappling with how to meet state requirements for recycling food waste and are pleased to offer a complete and cost-effective solution.” The purification system is capable of producing the RNG equivalent of 2,000 gallons/day of gasoline (760,000 gasoline gallon equivalents/year), which is dispensed at the Sanitation Districts’ nearby fueling station that is open to the public. Only pipeline natural gas was used for fueling at this station prior to having RNG available.

The digesters produce about 5,000 standard cubic feet per minute (scfm) of biogas, some of which is used to keep the reactors mixed and heated. Some is sent to the Sanitation Districts’ power plant located at the Carson facility. The remaining biogas is sent to the new purification system to make fuel grade RNG. “Because the Sanitation Districts manage both solid waste and wastewater, we already had most of the infrastructure needed for food waste recycling,” explained Bob Asgian, head of the Sanitation Districts’ Solid Waste Management Department. “We also received a grant from the California Energy Commission that helped fund the new biogas purification facility. As a result, we were able to complete our system relatively inexpensively and pass those savings onto our customers. Use of our system has been steadily growing and we have additional available capacity to help more cities.” READ MORE