Pretreatment of Paddy Straw for Sustainable Bioethanol Production

Abstract

Bioethanol production and its demand in India will be an increasing trend in the future. There are huge quantities of lignocellulosic feedstocks available for bioethanol production to fulfil the growing bioethanol demand. For lignocellulose-based bioethanol production, biomass pretreatment is an inevitable process for even the best lignocellulosic feedstock produce bioethanol. Paddy straw is a lignocellulosic agricultural residue obtained after the threshing process and it has challenges in safe disposal due to its low bulk density, inefficient burning methods and associated environmental pollution. To overcome these issues, paddy straw can be effectively used for bioethanol production after biomass pretreatment. Several pretreatment methods like chemical, irradiation, hot water, fungal, popping, and enzymatic pretreatment are available to pretreat the straw for bioethanol production. The pretreatment processing cost is almost 33% of the total cost of bioethanol production, which is the main barrier for bioethanol industry to run economically. The selection of an appropriate pretreatment method still remains one of the significant hurdles in economic bioethanol production from paddy straw. The use of paddy straw has a dual advantage as it is not only used as feedstock for bioethanol production, but will also help in controlling environmental pollution related to the burning of waste in the field. This chapter discusses the different pretreatment technologies used for paddy straw to remove the lignin content and how it is further used to produce bioethanol.