Optimization of Biogas production by Co-Digestion of Sawdust and Piggery Dung

Abstract

The Co-digestion of Sawdust (SD) with Pig Dung (PD) to produce biogas was studied. The objective of this paper is to increase biogas yield by  comparing combinations of sawdust and piggery dung at different mixing ratios. The study also investigated the effect of Total Solids (TS) and  microwave pre-treatment on biogas yield. Different mixing ratios of sawdust and piggery dung were combined and investigated for potential biogas  production at Initial total solid (TS) of 5% and 10% in the co-digestion experiments. Results show that a maximum cumulative gas yield (CGY)  of 33.75 L/kg of biogas was obtained in 60 days for a SD-PD ratio of 1:2. Similarly, the CGY of 29.33L/kg was obtained for experiments carried out  with 5% TS. Experiments carried out at SD-PD ratio of 1:1 showed lower biogas yields when compared to experiments at SD-P 1:2 with 10% TS for  SD-PD 1:1 giving a maximum biogas yield of 27 L/kg and 5% TS giving 22.5 L/kg. The results obtained also show that microwave pretreatment of  sawdust improved biogas yields by 13.1-16.7%.