ABSTRACT

Over the years fossil fuel has been the major source of energy, this fuel after passing through the process of fraction distillation produces different products used for power generation for the industrial sector likewise for domestic consumption therefore increasing its demand as well as price. Fossil fuel as a non-renewable source of energy tends to exhibit some flaws. Due to its non-renewable nature it emits pollutants during processing and consumption. This necessitated the need for an alternative source of energy called bio-energy. Bio-energy is produced from the fermentation of biomaterials in an anaerobic environment. It can be used as a fuel or as starting material for the production of chemicals, hydrogen and/or synthesis gas etc. The main constituents of biogas are carbon dioxide (CU2), hydrogen suiphide (H2S), water vapour with negligible quantities of contaminants, such as ammonia (NH3), methyl siloxanes, nitrogen (N2), oxygen (02), halogenated volatile organic compounds (VOCs), carbon monoxide (CU) and hydrocarbons. These contaminants presence and quantities depend largely on the biogas source. Howeyer, its hydrogen sulphide and carbondioxide content must be eliminated to avoid possible damages to equipment and hazards to users and the environment. To do this three stage purification methods was used, the first stage involve removal of H2S using iron chips followed by the removal of CO2using sodium hydroxide then silica gel was used to get rid of moisture in the gas. Afterwards analysis was carried out in other to ascertain the percentage constituents of both the raw and purified biogas using Pascal's Manometric glass tube technique. Also to determine the level of purity of the biogas. The result gotten after the purification showed biogas, CO2, and H2S content of 97.54-95.13%, 2.54-1.87%, and 2-0.5 ppm respectively in the biogas produced against the initial raw biogas content of 74.8-70.6 % o, 29.1-25.2 of CO2and 50-35 ppm of H2S. With a lower heat valve (LHV) of 9.8± 0.2 for purified gas and 7.1± 0.2 for raw biogas. from the result of the analysis it can be concluded that the removal of these contaminants especially H2S and CO2significantly improved the quality of the biogas for its further uses.