Portland Facility to Recycle Food Waste into Energy

In what is expected to be the first of its kind in the U.S., a facility that will recycle food waste into energy has been approved for construction in northeast Portland, Ore.

The Portland Metro Regional Council unanimously approved a franchise permit for Columbia Biogas to operate a facility in northeast Portland that will recycle food waste from commercial and industrial sources, keep about 200,000 tons of waste out of landfills or the sewer system, and produce enough electricity to power up to 5,000 homes.

Columbia Biogas plans to convert local food waste into renewable power, clean water, fertilizer and soil amendments. The anaerobic digestion operation will be located in an industrial-zoned portion of the Cully area in northeast Portland. Anaerobic digestion is a controlled and enclosed biologic process that breaks down organic matter without oxygen oxygen and produces methane-rich biogas that can be burned to make electricity.

Columbia Biogas plans to operate power generating engines that will produce about five megawatts of electricity and to connect to a substation grid in the PacifiCorp system. The digestion process also produces a byproduct that can be used as fertilizer and soil amendments in nurseries and farms.

The facility will be capable of processing about 90,000 tons of solid food waste and 104,000 tons of liquid food waste per year. The material will be processed in tanks in an enclosed building. Solid food waste will come from local commercial sources such as grocery stores, restaurants and food processors. Liquid food waste will come from commercial grease traps and food and beverage processors. Liquid waste is currently sent down sewers and treated at wastewater plants. No yard debris or garbage will be accepted.

Although Columbia Biogas must also receive a permit from the Oregon Department of Environmental Quality, construction is expected to begin in summer 2011.