Prozesu Katalitikoak eta Hondakinen Balioztatzea

Ikerketa Taldea


Kinetic modelling of pine sawdust combustion in a conical spouted bed reactor

Abstract: A model has been proposed and validated for the prediction of biomass combustion rate in a conical spouted bed. The model couples the intrinsic kinetics for the process and the flow pattern of the gaseous stream in the unit. The kinetics is described based on a reaction scheme consisting in simultaneous devolatilization and combustion involving the three biomass constituents, i.e., hemicellulose, cellulose and lignin. The gas flow pattern in the combustion chamber and subsequent cleaning system has been modelled using a compartimental model based on two continuous perfectly mixed vessels and a plug flow vessel. Tracer tests have been conducted to determine the residence time distribution in the whole unit and the parameters of the compartimental model. Batch combustion tests have been carried out to determine the composition of the outlet gaseous stream and the evolution of conversion with time, whose fitting to the kinetic model allowed calculating the parameters of best fit (frequency factors and activation energies). The model suitably predicts the evolution of combustion rate in a conical spouted bed, and therefore is a useful tool for the design of industrial plants based on this technology.