Bacterial Succession in Biogas Generation from African Wild Cocoyam (Colocasia esculentum), Poultry Droppings, And Cassava (Manihot esculentum) Liquor

Studies were carried out to determine the bacterial population present during anaerobic digestion of wastes. The ability of three organic wastes (African wild cocoyam, poultry droppings, and cassava liquor) to generate biogas as an alternative energy source was also investigated in the laboratory using the simple single state digesters of 1:3 working volumes with 50days retention time. From the investigations, it was observed that microorganisms such as species of Escherichia, Proteus, Staphylococus, Pseudomonas, Klebsiella, Serratia and Enterobacter were found to be present in the raw substrates. After ten days of anaerobic digestion, Klebsiella sp, Enterobacter sp, Escherichia coli, Staphylococcus aureus, Proteus sp and Serratia sp dominated. After twenty days of digestion, Klebsiella sp, E. coli and Streptococcus sp were found present. These same organisms dominated the digesters after thirty days of anaerobic digestion. However, after forty days of digestion, methanogenic bacteria such as Methanobacterium sp, Methanogenium sp and Methanococcus sp were isolated at this final stage where methane was produced. Peak biogas generation was recorded after 35 days of anaerobic digestion.