Effect of Solids Concentration in Cow Dung on Biogas Yield

Abstract

This paper focuses on the utilization of animal waste in particular cow dung to produce biogas with the aim of finding the effect of substrate concentration on total biogas yield. The batch anaerobic digestion experiment was conducted using the Automatic Methane Potential Test System (AMPTS II). The experiment was conducted with 10%, 20%, 50% and 65% solids slurry and the results show that methane yield increases with an increase in solids concentration but only up to 20% where after the biogas production goes down. The digester that had cow dung at 20% solids produced a higher accumulated gas volume of 12790.5 Nml (equivalent to 14267.55 ml) while accumulated gas volumes of 3128.4 Nml (3441.24 ml), 4021.6 Nml (4433.76 ml) and 704.4 Nml (774.84 ml) were recorded for 10%, 50% and 65% cow dung respectively. The results from this study will prove to be very helpful in future because they can be used to improve the performance of anaerobic digestion.