Recycling agricultural waste
Synonyms: Managing farm wastes
Utilizing agricultural wastes
Using agricultural wastes
Context: Pigs are able to utilize only 50% of the feed they consume, the rest of which is returned as waste. In management terms this is considered a poor return on investment as well as poor use of resources.
Implementation: The Berrybank Farm piggery in Victoria, Australia, produces a daily average of 275,000 liters of sewage effluent with an organic solids content of approximately 2%. This compares to the sewage output of a town with a population of about 50,000 people. The waste management system developed at Berrybank Farm recovers all the waste and transforms it into various by-products that can be used on the farm, such as flush water for farming, gas for electricity, and fertilizer. The system is a seven stage process comprised of 1) automatic continuous collection; 2) grit removal; 3) slurry thickening; 4) primary digestion; 5) secondary digestion; 6) biogas purification; and 7) a co-generation thermic plant. Initiated in 1989, the waste management process of Berrybank Farm started producing electricity in 1991. Each day the farm recovers: approximately 7 tons of waste solids at 35% dry matter, to be used as fertilizer; 100,000 liters of recyclable water; 100,000 liters of mineralized water, used as fertilizer; and, 1,700 cubic meters of biogas, able to run a co-generation electricity program with a daily output of 2,900 kW of electricity.
Subjects: WasteAgricultureFarmingManagement Resource utilization
Type Classification: D: Detailed strategies