Microbial Analysis and Biogas Yield of Water Hyacinth, Cow Dung and Poultry Dropping Fed Anaerobic Digesters

Abstract

Aim: Biogas research and subsequent production is fundamental to mitigating the possible depletion of crude oil and energy crisis, especially in Nigeria. This research paper was aimed at evaluating the biogas production capacity of water hyacinth, poultry droppings, cow dung and their combination. Methods: One kilogram, two kilograms and three kilograms weight of these substrates were subjected to anaerobic digestion in starter and without starter cultures for 45 days at the interval of 5 days. Results: Our results showed that heterotrophic bacteria and fungi counts were substrate-specific with poultry dropping fed-digester having the highest. Different bacteria and fungi were isolated including methane-producing bacteria such as methanolreoibacteria, methanoculleus bourgense, methanogenium cariaci, methanocorpusium parvum, methanoscrcimon barkeri, methanoplanus lunicola, methanococcoides methyluteus and methanothrix sochngenic. There were significant differences in the amount of biogas produced by the different substrates. However there was no significant differences (P>0.05) between the biogas produced by water hyacinth-fed digester (170.41mls) and poultry droppings-fed digester (182.88 mls). Combining all the substrates (WH+PD+CD) yielded the highest biogas (423.80 mls), which was followed by biogas production of cow dung (331.8 mls). Conclusion: Explicitly, our present report showed that higher biogas yield can be achieved by the combination of different biogas feedstock.