(53a) Biogas Technology: The Energy, Environment and Health of the Developing Nations

There are to date more than 3.5 billion people, mostly in developing countries, who still rely on coal and biomass—such as wood, dung, and crop residues—as their main source of energy for both cooking and heating. These traditional sources of energy can be extremely polluting and cause serious environmental health problems. Women and children are at greater risk because of household responsibilities and increased exposure to air pollution. Biogas technology through a proper anaerobic digestion process offers a way out as it produces a gas that can be used for cooking without any environmental or health problem. This paper described the management of Cattle wastes through anaerobic digestion (AD) technology which has not been explored as an alternative energy production, pollution reduction measure and in tackling health-related problems associated with cooking. To demonstrate the potential of this technology, a 5m³ underground digester was constructed and used for biodigestion of cattle dung .The study was based in Ibadan, in southwest Nigeria.  The structures were built of concrete components. At mesophilic temperature range, the digester produced 1.5 - 2.5m³ of biogas which was purified by passing through columns containing iron nails, lime and calcium chloride. The anaerobic digestion of the organic wastes produced environmentally friendly and energy efficient gas.The gas produced little or no smoke compared with cooking with wood, dung or crop resideues.The user does not also complain about any health related problem. Nigerian Government is now working out a renewable energy policy which emphasizes renewable energy production in order to tackle environmental and health problems associated with the use of wood, dung and crop residues by households.