Establishment of kinetic parameters of particle reaction from a well-stirred fluidized bed reactor

A novel method is presented for experimental study of gas-particle reactions, based on realizing a well-stirred reactor as a small scale fluidized bed. This reactor is evaluated against the drop tube reactor and the thermo-gravimetric analyser. It shows to enable high heat up rates (similar to 10(4) K/s), long timescale observation (up to several hours), operation with small fuel particles (similar to 100 mu m) and accurate control of reaction conditions. Char reaction rates are established from real-time gas product analysis by FTIR spectroscopy, through a detailed data-analysis procedure. This procedure employs a particle surface-evolution model and accounts for sampling system signal attenuation. The validity of the well-stirred conditions is established, and the method is employed for char combustion and gasification. Highly consistent results for char gasification over a wide range of conditions (T = 800-1100 degrees C, C-CO2 = 19-76%), are used to demonstrate the establishment of kinetic parameters for an n-th order approach. Activation energy and order of reaction are found and compare well with the literature. (C) 2015 Elsevier Ltd. All rights reserved.