Assessment of the Level of Biogas Production Using Different Animal Wastes as Substrates

Abstract

The use of biogas as a means of satisfying energy demands is a viable alternative to fuel wood which results in the indiscriminate felling of tress. Animal wastes as organic substrates in the production of biogas provide a cheap and eco-friendly method of managing wastes. In this study, three different animal wastes (Cow dung: pH1=7.08, pH2= 7.32; Goats' droppings: pH1=5.49, pH2=5.26; and Chicken droppings: pH1= 5.49, pH2= 5.75) were used as substrates in the production of biogas, and the experiment was carried out at ambient temperature for a hydraulic retention time of three weeks. A set of three laboratory digesters was used in the experimental set up, and the performance of the animal wastes was assessed based on the volume and flammability of the biogas produced. The amount of biogas produced by the animal wastes in decreasing order is as follows; chicken droppings (18.27 Litres), cow dung (12.55 Litres) and goats' droppings (5.11 Litres). The order of flammability of the biogas produced is as follows: cow dung > goats' droppings > chicken droppings. In this study, cow dung produced the biogas of the highest quality and conclusively can be chosen as the best substrate for biogas production.