Anaerobic Digestion of Cow Manure for Biogas Production

Anaerobic Digestion (AD) has become a viable way to manage agricultural waste and produce renewable energy simultaneously. Cow dung is a particularly notable feedstock in this expanding field of study because of its high organic content, accessibility, and dual use as an energy source and animal waste. This study examines the effectiveness of using controlled anaerobic digestion to produce biogas from cow dung. The justification for using cow dung is due to it will assist the cattle industry developing a circular economy by lowering greenhouse gas emissions, enhancing waste management techniques, and promoting decentralised power systems. The performance of the AD process was assessed through the analysis of Total Solids (TS), Volatile Solids (VS), Chemical Oxygen Demand (COD), and Volatile Fatty Acids (VFA). Initially in the digestive process, a significant rise in VFA levels suggested that hydrolysis, acidogenesis, and acetogenesis were all actively proceeding. After 40 days of digestion, biogas tests showed a methane content of up to 60%, indicating that methane generation peaked during the methanogenesis period. Significant drops in TS and VS (between 92% and 99%) provided further verification of the high level of organic matter decomposition. Furthermore, 96.4% COD removal was achieved, highlighting the effective breakdown and conversion of organic material into CO₂ and CH₄, which are components of biogas. These results demonstrate the energy and environmental advantages of anaerobic digestion as a green waste-to-energy technology and support the feasibility of using cow dung as a feedstock for biogas generation.