Technical and Economic Assessments of Biogas Production in a Family Size Digester Utilizing Different Feedstock Rotations: Döğer Case Study

Abstract

One of the key concerns of biogas plants with energy generation is the disposal of comparatively large amounts of digestate in an economically and environmentally sustainable manner. Anaerobic digestion of dairy cow manure (CM), sheep dung (SD), and energy maize (EM) was investigated with a 15-m3 anaerobic digester (AD) installed in a farm. In this study, technical and economic analysis for each feedstock rotation was carried out. The CM was investigated as single and combined feedstock. The single waste digestion of CM resulted in 10.49 m3 of methane (CH4) per ton. Co-digestion of CM and SD, and CM and EM, respectively, resulted in 10.92 and 13.79 m3 of CH4 per ton of organic dry matter (ODM) bases. In this article, the economic performance of the given biogas plant was analyzed based on the depreciation rates. The payback time for the experiments made with 100% CM, 75% CM + 25% SD and 75% CM + 25% EM is found to be 4.35, 4.23, and 3.92 years, respectively.