Ultrafast heating by high efficient biomass direct mixing with supercritical water

Abstract

This work analyzes the influence of the mixer configuration on the mixing efficiency in the process of biomass ultrafast hydrolysis by supercritical water. The results of the CFD simulations of a horizontal tee, a vertical tee and a mixing cross, selected as the optimum mixing configurations, together with the experimental results obtained in our hydrolysis plant, are the base to determine the configuration which provides the best mixing performance. Although slightly higher conversions are obtained in those experiments performed with a horizontal tee, the small differences between the results demand a theoretical analysis. Therefore, according to the CFD simulation results, since the mixing cross provides the best flow distribution and temperature homogenization at the outlet of the mixers and because of the great similarity between the residence time distribution curves of the mixers, the mixing cross is selected as the optimum geometry to perform the mixing.