Indexed by:期刊论文

Date of Publication:2010-10-01

Journal:INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

Included Journals:EI、SCIE、Scopus

Volume:35

Issue:19

Page Number:10271-10284

ISSN No.:0360-3199

Key Words:CFD; Simulation; Glycerol; Steam reforming; Fluidized bed reactor

Abstract:Hydrogen production from steam reforming of glycerol in a fluidized bed reactor has been simulated using a CFD method by an additional transport equation with a kinetic term. The Eulerian-Eulerian two-fluid approach was adopted to simulate hydrodynamics of fluidization, and chemical reactions were modelled by laminar finite-rate model. The bed expansion and pressure drop were predicted for different inlet gas velocities. The results showed that the flow system exhibited a more heterogeneous structure, and the core-annulus structure of gas solid flow led to back-mixing and internal circulation behaviour, and thus gave a poor velocity distribution. This suggests the bed should be agitated to maintain satisfactory fluidizing conditions. Glycerol conversion and H-2 production were decreased with increasing inlet gas velocity. The increase in the value of steam to carbon molar ratio increases the conversion of glycerol and H-2 selectivity. H-2 concentrations in the bed were uneven and increased downstream and high concentrations of H-2 production were also found on walls. The model demonstrated a relationship between hydrodynamics and hydrogen production, implying that the residence time and steam to carbon molar ratio are important parameters. The CFD simulation will provide helpful data to design and operate a bench scale catalytic fluidized bed reactor. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.