Simulated Performance of Reactor Configurations for Hot-Water Pretreatment of Sugarcane Bagasse

During the pretreatment of cellulosic biomass for subsequent microbial or enzymatic processing, the fiber reactivity typically increases with increasing severity but so does sugar degradation. Experimental results with sugarcane bagasse show that this tradeoff can be mitigated substantially by pretreatment in a flow-through (FT) mode. A model that incorporates both kinetics and mass transfer was developed to simulate the performance of pretreatment in plug flow, counter-current flow, cross flow, discrete counter-current and partial FT configurations. The simulated results compare well to the literature for bagasse pretreated in both batch and FT configurations. A variety of FT configurations result in sugar degradation that is very low (1-5%) and 5-20-fold less than a conventional plug flow configuration. The performance exhibits strong sensitivity to the extent of hemicellulose solubilization, particularly for a conventional plug flow configuration.