A Road Map on Biohydrogen Production from Organic Wastes

Fossil fuels play important role in the economy of industrialized countries of the world. However, these sources of energy are not renewable and nearing the brink of extinction. Moreover, the reliance on these fuels has led to increased levels of pollution which have caused serious adverse impacts on the environment. Hydrogen has emerged as a promising alternative since it does not produce CO2 and also has the highest calorific value. The biological H2 production has an edge over its chemical counterpart mainly because it is environmentally benign. However, the major challenge limiting the transition from an oil based economy to that of biohydrogen is the low hydrogen production rate, yield and economy of the process. Biohydrogen production by dark fermentation is found most promising as compared to other biohydrogen production processes like photo fermentation process using photofermentative bacteria, microalgae, microbial fuel cell etc. Present research group has been involved in biohydrogen research for last two decades. Suitability of different organic wastes for the hydrogen production has been developed. Both pure microbial cultures and acidogenic cultures obtained from anaerobic digester are found suitable for the hydrogen production. One 10,000 L pilot plant studies are carried out for the commercial exploitation of the process. The spent medium of the dark fermentation process mostly comprises of acetic acid, butyric acid etc., which are the substrates for the biomethanation process for the generation of methane and carbon dioxide. So, maximization of gaseous energy is possible dark fermentation followed by methanation process which is known as biohythane process.