Performance and effective kinetic models of methane steam reforming over Ni/YSZ anode of planar SOFC

摘要

Under mass/heat transfer and species diffusion limitations, the detailed thermodynamic investigations and experimental measurements were carried out to study and evaluate the performance of methane steam reforming and to develop its effective kinetic models over Ni/YSZ anode of the planar solid oxide fuel cell developed by Central Research Institute of Electric Power Industry (CRIEPI) of Japan. Based on the kinetic models of methane steam reforming developed by Xu and Froment, the effective kinetic models were developed. Combining the experiment data with the iteration calculation, the effective factor (C_e) is found to be 5.0 × 10~(-4). Using these effective kinetic models, the detailed distributions of temperature, species, methane conversion, and carbon formation and gasification activity are presented under wide range of operating conditions. The results show that the local temperature in the reactor and the methane conversion are sensitive to the operating parameters. The region of the lowest local temperature and the most possible region of carbon formation are at the front of the porous anode sample. Due to the limitation of contact time, heat transfer and species diffusion, the methane conversion appreciably decreases with an increase of S/C ratio.