Anaerobic Co-digestion of Food Wastes, Algae, Pond Sludge and Cow Dung for Biogas Yield Enhancement as a Potent Approach to Reduce Carbon Footprints

Abstract

ABSTRACT Alternative energy sources such as biogas help us to minimise environmental issues such as desertification, pollution, erosion, and deforestation. In this regard, anaerobic digestion (AD) is one of the most ecologically favourable waste management technologies and it also represents a long-term fuel supply. The current research examines the production of biogas in an anaerobic digester using apple, vegetable, and fruit pulp wastes, algae and pond sludge mixed with cow dung using co-digestion. The response surface technique was applied to optimise the variables of co-digestion such as temperature, pH and concentration of wastes. Meanwhile, the United States Environmental Protection Agency (EPA) method was used to investigate the proximate analysis (fixed solids, total solids, volatile solids, and moisture content) of the wastes. The optimum values of daily biogas, cumulative biogas, cumulative methane and cumulative carbon dioxide were found to be 2008.7, 3401.8, 2266.3 and 1931.5 ml respectively. A desirability of 0.6 was achieved for at least 15 numerical solutions obtained using Design Expert Software. It was also observed that the rate of biogas yield is greatly affected by many factors such as temperature and total solid concentration.