Optimizing Biogas Generation from Blends of Sugarcane Bagasse

Abstract

Renewable energy has been the alternative source to global energy scarcity which involves renewable resources as more emphasis been put to prospective ways of converting agricultural wastes into energy to meet both the local and global demands.This work analyzed the use of sugarcane bagasse as substrate in biogas production as well as its codigestion with cow dung and chicken droppings. Seven digesters each of 2.5 litres capacity were charged in a ratio of 1:3 solids to liquid for a retention period of 30 days within a temperature range of 25-32 oC was used. Digester A contained 100 % bagasse, B contained 100 % cow dung, C 100 % chicken droppings, D contained 50 % bagasse and 50 % cow dung, E contained 50 % bagasse and 50 % chicken droppings, F contained 70 % bagasse and 30% cow dung and 70 % bagasse and 30 % chicken droppings for digester, G. Proximate and microbial analysis of the spent slurry were carried out. The result shows that sample C has the highest volatile solids and protein content of 56.68 % and 10.01 %. Biogas production was observed to be higher in digester C with cumulative gas yield of 3228.3 cm3 then digester B with 2816.6 cm3 and Digester A had the least gas yield of 681.4 cm3. Lightening test was observed by passage over limewater which result in catching fire except on digester C. Methane and other traces of gases test using gas analyzer shows 61.3 % methane with the least having 46.7 % methane on digester B and C. Pseudomonas spp, Entrobacter aerogenes and Staphylococcus aureus were found to be dominant in almost all the digesters. Further research is required to investigate large volume production and to improve gas storage techniques.