BIO-ELECTROCHEMICAL CONVERSION OF CO2 TO CH4 TOWARDS ENRICHMENT OF BIOGAS: A REVIEW ON BES AN EMERGING TECHNOLOGY

The need of new sustainable sources of energy is on the top priority to fulfil the demand of energy at
different corners today. Biogas is one distinct source from other renewable energy providing sources because of
its environment friendly as well as economic characteristics. Biogas does not have any geographical limitations
nor it requires advancedtechnology for producing energy, it is also very simple to use and apply.Although, Biogas
generated from anaerobic digestion process is a clean, carbon neutral and environmental friendly energy
alternative, raw biogas needs to be purified necessarily before using. The removal of impurities from raw biogas
which is referred as enrichment ensures its better applications and also enhances its calorific value. Fundamental
aspects of anaerobic digestion are briefly described in the paper. The paper mainly includes various biogas
enrichment techniques and their comparative studies have been made. A novel technique of bio-electrochemical
technique has also been briefly discussed.