16-10: Sugar production from lignocellulosic biomass

Glucose and xylose are intermediate products in the formation of several molecules, fuels or platform molecules. While cellulose is the most abundant organic molecule on earth and potentially the most important source of glucose, its exploitation is prevented by the general recalcitrance  of the substrates. The biofuel industry has pushed the research in this field since decades and different routes have been tested. One of the most important distinctive elements of the processes is the use of chemicals or steam to pretreat lignocelluloses and the use of biocatalysts. Because of the very different range in feed composition, especially when residues and waste are considered, the selection of the process has to be made on specific consideration on storability, digestibility, yield of the desired outcomes, waste management. It is generally agreed that the most important goals can be meet by coupling the hydrothermal pretreatments, such the steam explosion, and enzymatic hydrolysis. Pilot facilities are available at the ENEA Research Center of Trisaia to pursue this approach and testing the effect of pretreatment severity, detoxification, batch end fed batch enzymatic hydrolysis, sugar recovery. The paper highlights the general outcomes expected, both from experimental data and process simulation, in processing herbaceous feedstock with a continuous steam explosion system (150 kg_DM/h), dissolution in water, counter current belt filter separator,  hydrolyser reactor, concentration of C5 and C6 sugar streams.