Production of Methane Gas from the Dominant Organic Refuse for Renewable Energy Generation. A Case Study of Food Remains (Posho) and Peels (Matooke and Irish Potato) From Central Division in Kampala, Uganda
MetadataShow full item record
Methane is typically a gas produced by the anaerobic digestion of biodegradable materials, one of the most promising processes for the energetic transformation of waste to produce biogas. Food waste, which has become one of the global concerns because of its massive amount, contains high organic content, which is used by the microbes as nutrients to produce methane gas. The objectives of this study were to: (i) generate and quantify the amount of methane gas produced from a known mass of each of the three different most dominant organic refuse (Posho, irish potato and Matooke peels) within a specified period of time, (ii) compare which of the three dominant organic refuse produces more methane in a given period of time, acquired from Uhuru restaurant in the central division of Kampala city. Three different categories of organic refuse were considered: posho, Irish potato and matooke peels all mixed with cow dung as the inoculum and also which acted as a control. These fractions were assessed for their efficiency for methane gas production in a laboratory-scale digester for a total period of 5 weeks at a room temperature of 24–26 °C. The set up consisted of a digester which was of 5 litres capacity and it was filled with 1kg of the sample refuse mixed with 400g of the cow dung. The volumetric yield of biogas was noted weekly using water displacement method. The cumulative mean methane gas produced for 35 days was 5206 ml per 1kg for Irish potato peels, 2007 ml per 1kg for Matooke peels, 276 ml per 1kg for Posho and 150 ml per 400g for cow dung alone. Thus, mixed waste was found to be more efficient than cow dung for methane production; this was mainly related to the better C: N ratio in mixed waste. The differences in methane production across the treatments were significant (p < 0.05). There were no significant statistical differences (p > 0.05) in the cumulative mean volumes of methane gas produced from irish potato peels(5206 ml) and matooke peels (2007 ml), posho and matooke peels, but the volumes of irish potato peels and posho were statistically different (p < 0.05) after the Turkey.