PHOTO: TIM PORTZ
POWER¦
THWARTING MOISTURE: At the Shakopee facility, moisture levels are reduced from nearly 50 percent to less than 10 percent in the site's rotary dryer. After drying, they are stored in a covered holding area until they are loaded for final delivery.
and they process the material into a biomass flour. “We produce 20 to 25 tons per hour of biomass flour on average to feed our combustion process,” says Cook. The biomass flour is pneumatically conveyed into a metering bin on the boiler house, and then metered into the stream of primary air that conveys the fuel mixture to the burners and into the boiler. “In our process, we use a controlled and sustained dust explosion inside the furnace,” Cook adds. “That converts the chemical energy in the fuel into heat energy.” The resulting heat energy is used by Rahr Malting, and the power generated is distributed between Koda Energy and Rahr, with the balance supplied to Xcel Energy. Though currently experiencing downtime due to a late-April explosion, Koda is currently salvaging existing equipment not damaged in the event and will reuse it to build bigger, better and safer. The company is currently working a redesign of the fuel receiving, storage, and blending system, and is in the planning and funding stage for reconstruction, Cook adds. “We have
performed a thorough safety assessment on all potential aspects of the design to improve the safety factor of the fuel side of the plant.” In the meantime, Koda Energy is processing tree storm debris for the Minneapolis Park and Recreation Board and providing the resulting wood chips to Minneapolis residents. Since a June 21 storm, the MPRB has hauled away more than 1,000 semi truckloads of boulevard and residential tree debris that has ash trees intermingled with other tree debris. Koda Energy is grinding and double chipping the material to meet the Minnesota Department of Agriculture's compliance standards for preventing the spread of emerald ash borer. “We try to be good neighbors in our community and provide service where it is feasible to do so,” Cook says. After all, in the Dakota language, Koda means “friend.” Author: Anna Simet Managing Editor, Biomass Magazine asimet@bbiinternational.com 701-751-2756