Nowadays, hydrogen is an alternative resource which can address issues related to global climate change, air pollution, and energy security. Currently, most hydrogen is produced via a steam methane reforming (SMR) process that requires additional post purification process to sequestrate CO2 for high-purity hydrogen production. The three-reactor chemical looping (TRCL) process for high-purity hydrogen production with intrinsic CO2 separation is a novel concept derived from chemical looping combustion (CLC). A common TRCL system consists of a fuel reactor (FR), a steam reactor (SR), and an air reactor (AR). In order to design the TRCL process efficiently and operate it sustainably, the characteristics of reactions and hydrodynamics should be considered carefully. CFD simulations can help to predict the flow behavior of the solid-gas mixture inside the system, from that to optimize the design and operating conditions. The objectives of this project are: