Techno-economic feasibility for recovering biogas in a bio augmented municipal sewage plant

A techno-economic assessment study was conducted to consider the feasibility of recovering biogas in a bio agumentated municipal sewage treatment plant. A sewage plant with a capacity of approximately 20 ML/day and a plant operating capacity of 60% for 24 hours were considered. The sewage sludge analysis indicated a high total solids and chemical oxygen demand content. Biogas generation was monitored over a 30 day period with Hycura as the bio augmentation media at 0.05 g/L. Biogas with a methane content of 78% was achieved and the digestate collected as bio solids was rich in nitrogen, phosphorous and potassium. The plant had the capacity to produce 1 380 KWh of electricity per day and if a total investment of 2 million is made, a payback period of 5 years at an in internal rate of return of 18% will be realized.