Experimental Investigation of Energy Potentials of Kitchen Organic Waste

Abstract

In sub-Sahara Africa, kitchen wastes (KWs) are worthless product that are disposed freely on open refuse sites causing environmental pollution and aiding the spread of pathogenic diseases. With increasing population, demand for energy is constantly on the rise. Persistent rise in prices of fossil fuel products often result in shortage in supply of energy for both domestic and industrial applications in most developing nations. To solve the imbroglio created by the shortfall of energy, renewable energy can be explored: one viable source of such is the biomass. However, KWs have very high Carbon Nitrogen ratio (C:N) of 35:1. The preceding statement then implies that if co-digested in appropriate ratio with human faeces and allowed to degrade inside an anaerobic digester, KWs have a disposition to drastically reduce the problems of inadequacy in energy supply. In this paper, the slurry obtained from KW, human excreta (HE) and water (W) was anaerobically digested in batch digesters A, B and C under mesophilic conditions in ratio 5:1:6, 1:1:2 and 1:5:6 respectively. The results obtained were analyzed to determine the slurry with the highest biogas yield. The digester with label A has the highest yield of 8164 mL of biogas as against digesters B and C which produced 7060 mL and 2307 mL respectively from the same volume of slurries. This is attributable to the higher ratio of kitchen waste in digester A. The result obtained from this study is expected to promote a better understanding of biogas technology.