Experimental Investigation on the Effects of Digester Size on Biogas Production from Cow Dung

Abstract

This paper presents the experimental investigation on the effect of digester size on biogas production. Experiments were carried out to produce biogas from different sizes of digester. 1.4 kg of cow dung was used to carry out the experiments. The temperature throughout the period of experimentation was within ambient temperature of 25°C to 35°C. It was observed that the pH values of the Digesters fluctuate between 5.4 and 7.6. This may be due to the activities of acid. Digesters A, B, C, D and E, with volumes of 250 ml, 500ml, 1000ml, 2000ml and 3000ml, produced a total biogas of 625 cm3 , 715cm3 , 1635cm3 , 2082cm3 and 2154cm3 respectively. Digester size is an important factor which has a direct effect on the quantity of gas produced. For the total biogas produced per litre of digester size, Digesters A, B, C, D and E, produces 2500 cm 3 l -1 , 1430 cm 3 l - 1 , 1635 cm 3 l -1 , 1041 cm 3 l -1 and 718 cm 3 l -1 respectively.