Computational fluid dynamics was applied for sorption enhanced steam methane reforming (SESMR) operating in a circulating fluidized bed (CFB) riser. The solid mixtures consisted of Ni-based catalyst and CaO sorbent. The aim of study was to design a proper pilot-scale CFB riser which produced hydrogen (H-2) with both high purity and high flux. The design parameters and the reaction parameters were examined with 2(k) full factorial design. The significances of each parameter were analyzed by analysis of variance. Using the optimum result, the highest H-2 purity reached 98.58% in dry basis accompanied with the highest H-2 flux of 0.301 kg/m(2) s. The hydrodynamics of this optimum case showed that SESMR was nearly completed since 5.0 m height because axial and radial distributions of solid were well developed without excessive segregation between catalyst and sorbent. Thus, the H-2 purity and the H-2 flux approached fully developed within the riser height. (C) 2018 Elsevier Ltd. All rights reserved.