Impact Bioenergy commercializes portable microdigester

The system, delivered to Fremont Brewing Co. in Seattle, can convert between 960 lbs and 35,000 lbs of organic waste per week into liquid fertilizer and renewable natural gas.

Energy can be in the form of building heat, hot water, radiant heat, light, electricity, vehicle fuel, cooking fuel, and prime motion.

Digested food waste can be used as a liquid soil amendment, liquid fertilizer, dried fertilizer or compost. The liquid soil amendment has been approved by the Washington State Department of Agriculture for use on their partner’s certified organic farm, owned and operated by Seattle Urban Farm Co.

The HORSE has a blending and feeding arrangement that runs automatically to minimize labour costs. Gas storage is pressurized by the microbes using a water-based regulator system. Odour control captures and prevents odours with biocarbon, biofiltration and neutralization.

Safety systems include a gas ignition and combustion system, weather protection and secondary containment.

Impact Bioenergy is already planning delivery of a second machine, to be located in Auburn, Wash., and negotiations are underway for a third machine on Bainbridge Island. That project will be sponsored by Puget Sound Energy.

Impact Bioenergy can produce several machines per month and is exploring scale-up partnerships with several technology firms.

The company is receiving research and development support from the Small Business Technical Assistance Program at the Pacific Northwest National Laboratory.