Design and Utilization of a Microturbine in Anaerobic Wastewater Treatment

The Laramie Wastewater Treatment Plant (WWTP) currently uses aerobic treatment and digestion to produce a safe effluent and residual biosolids. The current design requires the use of powerful electric air blowers. The Laramie WWTP currently spends more than $400,000 per year on electric costs. By switching to anaerobic treatment, where wastewater constituents are biodegraded in the absence of oxygen, the number of required air blowers may be significantly decreased, thus lowering the operating costs. Secondly, anaerobic treatment and digestion produce renewable biogas containing methane. The biogas can be combusted in a microturbine to further reduce electrical demand. This work examined the design of the microturbines necessary to produce electricity from biogas and evaluated the technical, economic and environmental benefits that may arise from using microturbines in combination with anaerobic treatment at the Laramie WWTP.