Environmental and Technical Assessment of Biogas Production using Rice Straw

Energy consumption is increasing rapidly in the world and it is expected that unrenewable energy sources will expire in the future; therefore, new methods of energy production are becoming more common all over the world. Biogas is one of the new and clean energies, which is produced from anaerobic fermentation of biomass. Guilan province with 238,000 hectares of paddy lands has significant potential for biogas production from organic residues. In this way, this study was carried out to investigate the process of biogas production from the combination of rice straw and animal waste with the ratios of (0-100), (5-95), (10-90), (15-85), (20-80) respectively in three repetitions. The experiment was performed at mesophilic temperature by anaerobic digestion method in the 1/5 lit bottles. An economic and environmental assessment for replacement of biogas produced in this process with fossil fuels was implemented in the village of Pounel in Guilan Province. The results showed that the ratio of 10% of rice straw had the highest biogas production efficiency and by replacing the biogas, 21 percent will save in fossil fuel consumption. It will also prevent the emission of 328.42 kg of CO2 gas into the atmosphere per year.