From Waste To Energy
INDUSTRIAL ENGINEER – VOLUME 45 NUMBER 3
Federal design standards could prompt dairy farmers to increase their use of anaerobic digesters that turn cow manure into electricity or natural gas, according to retired industrial engineer, Parker Holden.
He told the agricultural website capitalpress.com that dairies have a hard time making digesters pay off, face uncooperative electrical utilities and a difficult approval process from the Environmental Protection Agency.
Holden, who spent his career at Westinghouse and in the pulp and paper industry, said dairy farmers usually have little expertise in choosing and installing digesters and wastewater treatment systems. Standardized, efficient options already approved by the EPA and environmental groups could keep dairies from having to “reinvent the wheel”, he said.
Promus Energy in Seattle is in the design phase of biogas-to-renewable natural gas digester for two dairies, capitalpress.com reported. Dan Evans as its president, said new technology allows users to extract marketable fertilizer from digesters that in turn reduces the amount of nitrogen and phosphorous, the sources of groundwater contamination by 60 percent to 70 percent.