Novel Circulating Fluidized-Bed Membrane Reformer for the Efficient Production of Ultraclean Fuels from Hydrocarbons

Abstract

An integrated novel fluidized-bed membrane steam reformer for the efficient production of hydrogen is proposed and investigated. It consists of two connected subsystems, viz., a circulating fluidized-bed membrane reformer and a reactor−regenerator for dry reforming. The steam-reforming part is an extension of the previous successful work regarding a bubbling fluidized-bed membrane reformer. The fast fluidization regime is more efficient and productive than the bubbling regime. Hydrogen-permeable membranes to remove hydrogen are used together with a CO2 acceptor to remove carbon dioxide and enhance the performance. An in situ supply of heat through oxidative steam reforming is also suggested. The deactivated catalyst is regenerated and recirculated back to the reformer. The CO2-rich stream from the efficient fast fluidized membrane steam reformer is used in a reactor−regenerator dry reforming subsystem, and additional syngas is produced. A reliable reaction engineering model is utilized to investigate this novel configuration. A comparison between the predicted performance of the fast fluidized-bed reformer and the industrial data for a fixed bed as well as the pilot-plant data of the bubbling fluidized-bed configurations investigated earlier shows that the fast fluidized bed is more efficient and productive.