Landfill Gas Treatment Evaluation and Design

This food processing facility had been fueling two of its plant water tube boilers with local landfill gas, which caused a significant reduction in boiler efficiency and fouled the boiler tubes. Meanwhile, sulfur compounds in the untreated landfill gas and the subsequent sulfur oxide (SOX) content in the flue gases were causing significant corrosion of boiler economizers. The facility discontinued landfill gas as a fuel source for the boilers, but still sought other opportunities for utilizing the landfill gas to offset natural gas consumption and meet its sustainability goals. Mead & Hunt evaluated various treatment technologies for average flow of 1,000 SCFM of raw biogas, including activated carbon adsorption, silica adsorption, water scrubbing, pressure swing adsorption (PSA), and membrane separation. We also assessed the feasibility of utilizing the landfill gas in biogas boilers or a cogeneration system. The technologies were ranked based on environmental sustainability, energy usage, financial feasibility, and reliability. After we reviewed the alternatives with the facility, our team performed preliminary engineering for the selected gas treatment system, which included accepting biogas from the proposed anaerobic digester that would supplement the contribution from the landfill gas supply. We prepared design drawings, a major equipment list, an overall project schedule, and budgetary pricing for implementing the proposed system.