Abstract

                                Development of sustainable energy systems based on renewable biomass feedstock is now a global effort. Fuels produced from biomass have the potential to reduce reliance on petroleum resources and reduce greenhouse gas emissions. Biofuels obtaining from coproduced residues remains one of the major challenges in full scale opera- tions. This study investigated the potential of an anaerobic digestion system to convert the stillage obtained from pearl millet based lignocellulosic biofuel production. Biomethanation experiment study was conducted in CSTR using acid pretreated pearl millet based biofuel stillage upto 30 days. Using SAS software the multi colinearity was identified among different parameters of pH, TS, VS and VFA profile were analysed for identifying the major factor impacting biogas production. The initial parameters of stillage were pH 6.8, VS 978 mg.l-1, TS 988 mg.l-1 and VFA 802.44 mg.l-1. The maximum biogas production 0.17 L was obtained at neutral pH of 7.4 on 16th day with respect to reducing the VFA 9.45 m mol.l-1 acetate, VS 954 mg.l-1 and TS 973 mg.l-1 after which there was reduction in the gas production due to alkaline pH even though TS, VS and VFA were reduced.

Key words : lignocellulosic biomass, Acid pretreatment, Stillage, Anaerobic digestion and Continuous Stirred Tank Reactor