Wednesday, February 15, 2017
How to turn cow manure to biofuel.
The San Joaquin Valley has become America’s breadbasket over the past few decades. Products including pistachios, almonds, citrus, stone fruit, cotton, and grapes are grown here and distributed all over the United States and are exported around the world. The agricultural waste creates a solid biofuels pipeline and eliminating these waste, especially cow manure, is becoming expensive and of course, problematic for the local environment.The recent launch of the Calgren Ethanol Plant is a step in helping California meet its clean energy goals while addressing the San Joaquin Valley’s terrible air pollution. The plant, according to the coalition of companies that built the facility, will churn cow manure into bio-ethanol which can then be blended with conventional gasoline. The process starts with a nearby dairy, Four J Farms. Cow manure from the 1,800 milk-producing cattle will flow down a pipeline to the Calgren plant. The manure is then deposited into the DVO-designed digester that is 16 feet deep and insulated with concrete to prevent any leakage from entering local groundwater. Bacteria that naturally occur within cows’ digestive tracts are added to the manure, when is then stored and churned there while it is kept at a consistent warmth of 101.5°F (38°C). The three-plus weeks the manure is kept at that temperature is to guarantee any pathogens would be killed off, including E. coli. The result is a system that works almost exactly like a cow’s digestive system. When the clean fuel is culled from the manure, moisture is also extracted and then recycled so local farmers can use it to water their crops. The by-product that remains at the end of the process, which emits almost no smell and has a consistency of moss, is then trucked back to Four J Farms, where employees then scatter it to use as animal bedding. Steve Dvorak, President of DVO, said that one cow alone creates about 100 to 130 cubic feet of biogas a day, or the equivalent of 65,000 BTUs or 6 kilowatt-hours daily,thus there is enough organic waste (in California) to power 2 to 3 million homes or to generate 2.5 billion gallons of clean, ultra-low carbon transportation fuels. source