Technologies for Utilization of Biogas as Energy Source: A Review

Abstract

Energy is fundamental to the quality of our lives. Energy growth is directly linked to well-being and prosperity across the globe. Meeting the growing demand for energy in a safe and environmentally responsible manner is always being a key challenge. Among so many alternative biofuels, there exists a clean and better fuel (biogas) that can help us cope up with the growing energy demand. Biogas is produced by anaerobic digestion of biodegradable solid waste, which is not only an environmentally sound and sustainable energy source but also provides a cleaner and safer route to dispose of the solid waste and make surroundings more hygienic. Raw biogas mainly consists 50-70% methane and 30-50% carbon dioxide with traces of some other impurities like, hydrogen sulphide and siloxanes etc. Biogas is considered to be a better alternative fuel as it is ecologically attractive, has considerable calorific value of 20-26 MJ/m 3 , provides cleaner and reliable energy source, reduces greenhouse effect, a cheaper technology, and can have very compact design too. Despite of having number of benefits over other fuels and vast field of application, biogas is not that popularly accepted among common people because of many reasons such as lack of knowledge for substrate selection, pre-treatment and post-treatment cleaning requirement, and various routes/technologies available for its utilisation. Thus considering the capability of biogas to serve many energy industries, we need to emphasize on technological advancement to make this fuel an independent system. In this paper we have mainly focused on various gas-to-energy technologies to recover energy from biogas for its maximum utilisation.