In the United States (US), Chilton, Wisconsin (WI) based DVO Inc., a developer of proprietary Two-Stage Mixed Plug FlowTM anaerobic digester (AD) systems has announced that Installation and construction are nearly complete on an AD unit scheduled to open at Calgren Renewable Fuels on September 30, 2014, in Pixley, California (CA). This is DVO’s first installation in California, and the state’s only next-generation anaerobic digester.
Anaerobic digestion (AD), is a collection of processes by which naturally occurring microorganisms transform waste into valuable byproducts in a controlled, oxygen-free environment. DVO’s patented Two-Stage Mixed Plug Flow anaerobic digester is unlike any other technology. Traditional AD technologies featuring above-ground tanks are “inefficient and costly to operate”, the company says.
The DVO anaerobic digester, built by Andgar of Ferndale, Washington, is designed to hold approximately 1.4 million (US) gallons (≈ 5.3 million litres) of manure and organic waste. Each day, the digester will receive 55,000 gallons of solid and liquid waste from Four J Farm Dairy, a nearby dairy farm with approximately 2 000 head of cattle.
Biogas, one of the many valuable byproducts of the anaerobic digestion process, will replace thousands of gallons of natural gas currently being used by the Calgren on-site cogeneration facility to produce 55 million gallons (≈ 208 million litres)of ethanol each year.
Biosolids, another beneficial byproduct of anaerobic digestion, will be sent back to Four J Farm Dairy to be used as a high-quality and low pathogen count cattle bedding. Liquid nutrients from the digestion process will also be used at farm to fertilize growing crops.
The Calgren facility and Four J Farm Dairy will not be the only ones to benefit from the addition of DVO’s anaerobic digester. Our digesters reduce the environmental impact from farm waste greenhouse gas emissions by over 90 percent, pathogens in the digested waste are greatly reduced, often to the point of non-detection, and up to 97 percent odor reduction is achieved as biogas is burned, said Steve Dvorak, owner and founder of DVO.
The DVO anaerobic digester at Calgren will be cost-effective and reliable. Staff members at Calgren will facilitate daily operations and routine maintenance of the digester.
