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BED SHERWOOD NUMBER AND CHEMICAL KINETIC COEFFICIENT IN A FUEL REACTOR OF CHEMICAL LOOPING COMBUSTION BY EULERIAN CFD MODELING a a a a Ari Vepsäläinen *, Srujal Shah , Petteri Peltola and Timo Hyppänen aLappeenranta University of Technology, LUT Energy; P.O.Box 20, FI-53850, Lappeenranta, Finland *T: +358405654584; F: +358056216399; E: ari.vepsalainen@lut.fi ABSTRACT The transient Eulerian two-phase CFD model applying the kinetic theory of granular flow is used to simulate two pilot scale test balances in a fuel reactor of chemical looping combustion with methane as fuel and nickel-based oxygen carrier. The kinetic reaction rate coefficient of Nickel-based oxygen carrier particles is defined based on the measured total methane conversion, and correspondence with the experimental data was found. The bed Sherwood numbers were derived based on the CFD simulations. The derived correspond to the in-literature presented data, and explain the commonly faced problem of obtaining different chemical kinetic coefficients from the TGA and bench-scale fluidized bed reactor tests. INTRODUCTION A comprehensive review of the process research of chemical looping combustion (CLC) and oxygen carrier material development is provided by Adanez et al. (1). Feasible operation of chemical looping combustion with gaseous fuels has been proven in a pilot plant scale. Pröll et al. (2) reported stable operation of 120 kW CLC pilot th plant with high conversion rates for gaseous fuel (methane) and nickel- based oxygen carrier (Fig. 1). In a technology development, the next demonstration scale is 1-3 MWth Figure 1 CLC process with methane (Adanez et al. (1)). combustion and NiO oxygen carrier From a