QUANTITATIVE AND QUALITATIVE ANALYSIS OF BIOGAS PRODUCED FROM THREE ORGANIC WASTES

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: pH 1 =7.08, pH 2 = 7.32; Goats’ droppings: pH 1 =5.49, pH 2 =5.26; and Chicken droppings: pH 1 = 5.49, pH 2 = 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 quality 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.  The following methanogens were isolated; Methanobacterium sp., Methanococcus sp., Methanospirillum sp. and Methanosarcina sp. in the course of the experiment. In this study, cow dung produced the biogas of the highest quality and conclusively can be chosen as the best substrate for biogas production.