Panelists at the Waste-to-Fuels Conference detail their companies’ anaerobic digestion projects.
Siting is generally the most difficult part of a biogas project, according to Kevin Matthews of CCI BioEnergy, Newmarket, Ontario, Canada. He advised attendees considering anaerobic digestion (AD) technologies to be truthful about the possibility for odor and to design facilities so that it is managed at all stages. Matthews was part of a panel on anaerobic digestion (AD) conversion technologies at the 2012 Waste-to-Fuels Conference & Trade Show, Sept. 16-18 in Groton, Conn.
Also speaking on the panel were John McDowell of Eisenmann (www.eisenmann.us.com), Crystal Lake, Ill., who outlined a future biogas plant installation in Chicago, and Amber Blythe of BIOFerm Energy Systems, Madison, Wis., who provided details about a biogas plant in operation at the University of Wisconsin.
CCI BioEnergy is a wholly owned subsidiary of Canada Composting Inc. and holds the exclusive Canadian and U.S. license rights to an AD technology known as "The BTA® Process.” CCI BioEnergy acts as the operator of the technology and gets paid based on production results, Matthews said. Currently, the company is involved with three plants in Canada, including the Toronto Dufferin facility, which has been in operation for 10 years, the Toronto Disco facility, which will be operational in 2013, and a plant in Newmarket, Ontario.
At 100,000 tons per year, the Dufferin facility is operating at three times its designed capacity, Matthews said.
The city of Toronto generates 150,000 tons per year of source-separated organics, he said. When the Disco plant is completed, it will process 75,000 tons of material, while Dufferin will process 60,000 tons. The remaining 15,000 tons of material will go to a third-party for processing, Matthews said. The BTA Process produces compost, pipeline-grade gas and electrical generation from the organic material.
Matthews said that for every 1 metric ton of waste the system processed, it produced 115 cubic meters of biogas, 65 percent of which was methane, and 0.31 metric tons of digestate.
Eisenmann’s McDowell described the biogas plant his company is supplying to The Plant, which calls a 93,500-square-foot former meatpacking facility home. Eisenmann supplies regenerative thermal oxidizers (RTOs) to the renewable fuels industry in addition to supplying a variety of renewable energy products and waste-to-energy solutions.
According to The Plant’s website, www.theplant.com, the facility is “being repurposed into a net-zero energy vertical farm and food business operation. A complex and highly interrelated system, one-third of The Plant will hold aquaponic growing systems and the other two-thirds will incubate sustainable food businesses by offering low rent, low energy costs and (eventually) a licensed shared kitchen. The Plant will create 125 jobs in Chicago’s economically distressed Back of the Yards neighborhood – but, remarkably, these jobs will require no fossil fuel use. Instead, The Plant will install a renewable energy system that will eventually divert over 10,000 tons of food waste from landfills each year to meet all of its heat and power needs.”
The organic material for the renewable energy system will come from agriculture, food processing facilities, restaurants, yard waste and grass clippings and waste management facilities, McDowell said. Construction on the biogas plant is expected to begin in the fourth quarter of 2012, with startup expected in the second quarter of 2013, he said. The plant will employ a main digester (a high solids horizontal plug flow digester) and a secondary digester (a continuously stirred tank reactor), with capacities of 5,000 tons per year for phase one and 10,000 tons per year for phase two.
Among the products the system will produce are CNG (compressed natural gas) station/pipeline, electric energy, thermal energy, liquid soil amendment and solid soil amendment, he added.
The BioFerm biogas plant installed at the University of Wisconsin – Oshkosh is a dry ferment system, according Blythe, capable of processing 8,000 tons of agricultural or source-separated organics per year and producing 370 kilowatts of electricity and with a thermal capacity of 495 kilowatts. It features four fermentation vessels and began operation in summer of 2011.
Blythe said the university estimated that the plant will provide up to 10 percent of the campus’ electricity needs and the methane displacement is equivalent to 8,813 metric tons of carbon dioxide and an additional 1,942 metric tons of carbon dioxide are displaced by generating electricity from renewable sources.
In the pursuit of AD technology, Matthews advised attendees, “Success is all about managing expectations.” He reminded attendees that not all waste was the same, nor were all AD processes.
“Don’t let technique define your objectives. Let your objectives define technique,” he advised attendees who were considering AD technologies. He instead encouraged attendees to focus on their goals when pursuing AD technology: waste diversion, plant performance and system costs.
The Waste-to-Fuels Conference & Trade Show is organized by the Southern Waste information Exchange. The 2013 conference will be Sept. 15-17 at the Hyatt Regency Mission Bay in San Diego.