1. Introduction
Biogas is the combustible gas produced through a biological process, known as anaerobic digestion which is the process operated at low-temperature and without air. Biogas consists of 55– 80% CH4, 20–45% CO2 with trace amount of H2S and other impurities [1]. With its physical and chemical properties close to those of natural gas, albeit with a lower methane content, biogas can be used to boil water or for cooking instead of LPG, used as fuel for process heating, used for lighting purpose, produce electricity via internal combustion engine or used in replacement of diesel or gasoline
to drive equipment.