A pore level study of syngas production in two-layer burner formed by staggered arrangement of particles

A 2D model of simplified porous burner is developed to analyze the syngas production from fuel-rich CO2/CH4 partial oxidation with detailed chemical kinetics GRI-Mech 1.2. The geometry simulates a two-layer burner, which is composed of 2.5 mm particles in the upstream and 7.5 mm particles in the downstream. A 2D packed bed of connected particles with staggered arrangement is developed. The discrete ordinates (DO) model is used to compute the surface to surface radiation and gas radiation. The solid conduction between the neighboring particles is taken into account by bridge approach. The predicted results are compared with experiment and good agreement between the predictions and experiment is observed. The effect of CO2 injection in the system is examined. It is demonstrated that 2D pore level simulations by simplified geometry with detailed chemical kinetics can capture the features of syngas compositions and temperature profiles. Local information of species, temperature and velocity distributions within pores in the burner is presented and analyzed. Results show that thermal nonequilibrium in the same particles exists in the entire burner, and that chemical nonequilibrium for the main syngas of H-2, CO and CO2 is observed from exothermic zone to the burner outlet. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.