Measurements of Rheological Properties of Arundo Donax Suspensions and Enzymatic Hydrolyzates

An important requirement in cost-efficient lignocellulosics-to-ethanol process is to achieve concentrated hydrolyzates. The research in the last years has been focused on improving the enzymes performances in terms of internal dosage of the specific components and increased thermostability. These improved features could facilitate the processing of concentrated biomass suspensions up to 20-30% solids. However, the most important problem in the hydrolysis at high solid loadings is related to the fact that, these suspensions have a strong non-Newtonian behavior with high viscosities values that cause mixing and mass transfer limitations, and, presumably increased inhibition by intermediates. In this paper preliminary results from the rheological characterization of concentrated biomass suspensions are presented with the scope of gaining data for the process design and optimization. In particular various geometries have been evaluated for the rheological characterizations of these fluids (namely vane, plate/plate, cone/plate), and several tests were done to measure the viscosity, the, the consistency and fluidity index under different process conditions..
Proceedings of the 20th European Biomass Conference and Exhibition, 18-22 June 2012, Milan, Italy, pp. 1681-1684