Biogas production from rice straw by solid-state anaerobic digestion

Biogas production from lignocellulosic biomass can be used as an alternative fuel to replace fossil fuels. Lignocellulose can be obtained from agricultural crop residues, such as rice straw. The aims of this study were to determine the effects of F/I ratio, total solid content, and physical pretreatment on biogas production by solid-state anaerobic digestion. The kinetics of biogas production were also examined in this study. The results showed that the biogas yield decreased by the increasing of F/I ratio. Meanwhile, the increase TS content of 22% to 24% also decreased the biogas yield. Physical pretreatment had no a significant effect on biogas yield (p > 0.05). The highest biogas yield of 248.4 L/kg VS was obtained at an F/I ratio of 2, TS content of 22%, and particle size of 2 mm. The kinetics of biogas production from rice straw followed the first-order kinetic model with the highest rate constant (k) of 0.0861 day−1.