Salas O’Brien’s landfill client in Akron, Ohio, installed a landfill gas-to-energy (LFGTE) system that, combined with the anaerobic digester at a nearby composting plant, provides 95% of the two plants’ energy needs and saves the city $50,000 in utility costs each year.
Here’s some background on this important technology.
The US EPA’s latest report on waste management in the USA shows that 137.7 million tons of municipal solid waste (MSW) were landfilled in 2015. Municipal solid waste includes everything from paper and plastic products to yard trimmings and food waste. As the MSW naturally decomposes, it releases landfill gas composed of approximately 40-60% methane, a flammable greenhouse gas that’s 21 times more potent than carbon dioxide.
Landfills used to collect this gas and burn it—a process which eliminated the dangerous gas but contributed to air pollution.
Our client in Akron, Ohio, wanted instead to harness these emissions for use as a sustainable energy source. They requested our mechanical and electrical design team to develop a Landfill Gas-to-Energy system that would capture methane and convert it into a usable energy source for a nearby wastewater treatment plant.
Our team created an impressive LFGTE system that captures methane from the landfill and transports it to a sewage plant, where it then powers a Reciprocating Internal Combustion Engine (RICE) that partially powers the city’s wastewater treatment plant. This gas to energy project required innovative design for electrical and mechanical power systems and controls, such as a new electrical power generator and a gas conditioning system.
The gas conditioning system dries, conditions, and compresses the biogas for the engine, significantly improving the engine’s stability and reliability. The fuel system continually adjusts to fluctuations in the landfill gas and can successfully operate on gas between 400–600 Btu.
The finished design uses a new Waukesha 1000 APG Enginator that features cutting-edge “lean burn” technology. It can produce 8,600 megawatt hours of sustainable energy annually, saving greenhouse gas emissions equal to that of 9,111 passenger cars each year.