Do Sweat the Small Stuff: Micro-constituent Impacts on Beneficial Digester Gas Utilization

Anaerobic digester gas samples were taken at eight wastewater treatment plants (WWTPs) across the southeast United States, as well as, multiple samples taken over a 4 month period of one treatment plant. Results show limited variation in the major digester gas constituents (methane, carbon dioxide, nitrogen, etc.); however, there is great variation in hydrogen sulfide and siloxane concentrations. With multiple samples at the one WWTP, siloxane concentrations showed great variability, but appears to be related to the primary sludge loading of the anaerobic digesters. Digester gas sampling results are included.