Effects of catalyst distribution, particle geometry, and process conditions on the behavior of a water gas shift reactor under moderate pressures: a modeling study

In this paper, different geometries and types of catalyst distribution used for fixed bed WGS reactors that can be placed at the outlet of gasifiers have been studied. It has been shown that spherical eggshell catalysts allow significant reductions in catalytic mass compared to uniform pellets. Moreover, thanks to the possibility of using large pellets offered by eggshell catalysts, the pressure drops observed when using these particles remain acceptable (< 5%) even for a long reactor (Z = 2.8 m) and despite a low feed pressure (P-0 = 2.5 atm). Simulations also revealed that operating in isothermal or isoperibolic mode at low temperature (T = 630 K) improves significantly the process efficiency.