Process optimization and mass balance studies of pilot scale steam explosion pretreatment of rice straw for higher sugar release

The present study deals to visualise the impact of various process parameters, i.e. particle size and impregnation media over sugar released during steam explosion pretreatment. For this, 5, 10 and 20 mm rice straw sizes were impregnated in water and dilute acid media (1%) followed by steam explosion at 180 and 200 degrees C. Pretreated slurry was further hydrolyzed by 5 and 10 FPU g(-1) of residue varying 15 and 20% solid loading. The result showed that 10 mm particle size gave highest glucan conversion (88.7%) in acid impregnated steam explosion at 180 degrees C using 5 FPU g(-1) of residue with 15% solid loading. Comparatively, water impregnated pretreated biomass results significantly lower glucan conversion (61.1%), which was further intensified to 77.7% at 10 FPU g(-1) of residue with increased temperature. Furthermore, mass balance, compositional and structural transformation studies support our finding. Overall 30.6-81.1% sugar recovery was achieved with/or without acid pretreatment respectively.