(150e) Simulation of Commercial Scale Autothermal Chemical Looping Unit for Syngas Production
AIChE Annual Meeting
Monday, November 11, 2019 - 1:50pm to 2:10pm
Commercialization of the technology requires fundamental understanding of the reactions and reaction kinetics and of the fluid dynamics and eventual transport limitations. Reactor simulations with a sufficiently fundamental model can then be used to predict the methane conversion, syngas composition and required solids circulation rate under typical commercial conditions and to study catalyst and reactor design optimization. A 1D a-CLR reactor model accounting for the presence of bubbles and axial dispersion in the emulsion phase in the FR and for detailed reaction kinetics and catalyst deactivation by Ni oxidation is presented. An a-CLR unit equivalent to 50 commercial SMR pipes was then considered and the conditions allowing autothermal operation and sufficiently high methane conversion studied. It is shown that only a few % Ni oxidation in the AR is optimal as fully reduced Ni is required in the FR to be catalytically active. Autothermal operation and up to 97% methane conversion can be achieved at reasonable operating temperatures and OC circulation rate. Transport limitations were found important, the catalyst activity having only a small impact on the methane conversion. In a last part of the presentation, the influence of the main operating conditions is discussed and recommendations for further development of the technology given.