Sustainable Energy Production from Renewable Resources through Anaerobic Digestion Process: Nigerian Experience

Nigeria is a country with abundant, diverse and un-exploited renewable energy resources that are yet to be used for improving the livelihood of the vast majority households. The production of biogas via anaerobic digestion of agricultural residues, municipal wastes and industrial wastes (water) would benefit Nigerian society by providing a clean fuel in the form of biogas from renewable feedstock and help end energy poverty. These renewable resources include water hyacinth, chicken litters, cattle dung and cattle rumen. The focus of this paper is on the conversion of these resources to sustainable energy by using anaerobic digesters. The anaerobic digester is made up of 10 liters plastic keg which was designed for the purpose of this batch pilot-scale laboratory research work. The height, width and length of the digester were 28cm, 16cm and 22.4cm respectively. The diameter of the inlet of the digester was 3.8 cm. The diameter and length of the outlet tap were 2.9cm and 11cm respectively. Two and a half kilogram of cattle dung was measured and seven liters of water was added to it to form slurry. The total volume was measured with a calibrated bucket. The composite weight was also measured with a weighing balance. The slurry was poured into the digester and was properly sealed. The same process and measure was used for chicken litter, cattle rumen and water hyacinth. After few days of anaerobic digestion, the digester was swollen, the gas inside was tested to confirm whether it was biogas; but it was majorly carbon-dioxide because it does not support combustion and thus, it was released. Biogas was later produced on the thirtieth day as the gas combusted. The gas was measured by using the water displacement method. The amount of gas produced was monitored for ten days. The result of the findings was recorded. Chicken litter, Water hyacinth and Cattle rumen were treated in the same way and biogas production started on the twenty-eight, twenty-sixth and twenty-third days respectively. Nigeria is a haven for Cattle wastes, Poultry dropping, Water hyacinth and Cattle rumen. The utilization of these resources will provide sustainable energy for Nigerians.