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• A phenomenological design approach is constructed for the design of CLC-PPBR at/above pilot scale. • Macroscopic behaviors of the heat/reaction front are introduced to depict the dynamic operation of the reactors. • Bed size must conform to certain limitations to fulfill reasonable operational stability and cost-effectiveness. • Effects among design parameters are studied to optimize the preliminary design scheme for the 1.5 MW th reactor. The parallel packed bed reactor (PPBR) is a promising route for industrial application of chemical looping combustion. This paper introduces a phenomenological approach for the rational design of PPBR, serving as a manner to efficiently obtain comprehensive design results. Based on the macroscopic propagation of heat and reaction fronts, it elucidates the dynamic heat/mass transfer within the bed. Subsequently, it is applied to design a 1.5 MW th reactor. The risk of carbon deposition in the bed is firstly investigated from a thermodynamic perspective. Then, the study reveals that the height-to-diameter ratio of the reactor must meet certain constraints to ensure stable and cost-effective operation, and these constraints are extended to the scale-up process. Sensitivity analysis is utilized to investigate the effect of key parameters on the design schemes and performance. Effects of particle size on intra-particle gas diffusion is analyzed. Finally, detailed design schemes and performance of the reactor are determined. [ABSTRACT FROM AUTHOR]

An accurate and self-consistent methodology for mass transport of multi-component mixtures in multi phase media is a necessity for a proper description of complex physical and chemical processes in reactors such as catalytic packed beds. In this regard, a novel methodology has been developed to describe and couple underlying transport phenomena in fluid and porous media as well as at the solid-fluid interface. The methodology is symmetric as it treats all components in a mixture equally. The Maxwell-Stefan equations are symmetrically formulated, discretized conservatively and coupled with a compressible flow solver for the fluid part. The Dusty Gas Model is applied inside porous media by developing a self-consistent and robust numerical formulation. A ghost-cell Immersed Boundary Method is used to capture the physics at the solid-fluid interface with the implementation of a novel symmetric non-singular mass flux formulation. Several test cases are established to demonstrate the accuracy and robustness of the newly developed symmetric methodology in this paper. These test cases can be used as benchmark for the future development of symmetric methodologies for multicomponent systems in multi phase media. • A novel computational methodology has been developed to couple transport phenomena in fluid-solid multicomponent media. • The developed methodology is symmetric as all components in a mixture are treated equally. • A symmetric and unconditional stable formulation for the Dusty Gas Model has been developed. • A novel non-singular mass flux formulation has been developed and embedded in the ghost-cell Immersed Boundary Method. • Several test cases are designed for verification and validation of the developed methodology. [ABSTRACT FROM AUTHOR]