Biogas Production from the Co-digestion of Cow dung and poultry Droppings Using a Plastic Cylindrical Digester.

Abstract

This study was carried out to compare the rate and amount of gas produced from the co-digestion of two different substrates of cow dung and poultry droppings under anaerobic conditions. Biogas production from three(3) cylindrical bio-digesters containing cow dung, poultry dropping, and a mixture of cow dung and poultry droppings under an average temperature of 28°c and a pH of 6.2 was examined. In each case, the feedstock was diluted with equal volume of water to form slurry. The digestion took place for a period of 35days. The biogas produced during this period was collected by balloon method and subsequently measured and recorded. The results obtained from this study shows that the co-digestion of cow dung and poultry droppings yielded a maximum volume of 2.62 cm3, while poultry dropping yielded 2.50 cm3 and cow dung yielded 1.78 cm3. Thus, the co-digestion of the feedstocks gave a better gas production and the mean biogas yield was found to be significant (P<0.05) compared to each of the single substrates. This study has demonstrated that the co-digestion of cow dung and poultry droppings in a plastic cylindrical could be a cheap method for locally producing biogas for domestic purposes. It is, however, recommended that gas production can be enhanced during hot seasons where a higher temperature is easily attained.