De-construction of major Indian cereal crop residues through chemical pretreatment for improved biogas production: An overview

The expedition for inexpensive, renewable and environmentally friendly source of energy to replace the conventional sources like coal and petroleum is currently the most focused research area. Biomass resource in the form of crop residues is the abundant and readily accessible renewable resource. Wheat, rice and maize are the major cereal crops around the globe and are found to be the major sources of residual lignocellulosic biomass in the form of straw. In India, this is usually burnt in the field and is thus underutilized. These residues may be harnessed for bioenergy production by thermal and biochemical processes. This review is exclusively focused on chemical pretreatment of these residues to generate biomethane by unmasking lignin. The paper also reviews the essential properties of the residual biomass such as proximate, ultimate and compositional for the quality of derived biofuels (bioethanol and biomethane). Biomass to bioenergy conversion process, biomethane and bioethanol fermentation process and comparison of biomethane and bioethanol in terms of yield and energy value is also discussed. These cereal crop residual biomass contribute in the production of renewable and sustainable energy.