Modeling and Simulation of WGS Membrane Reactor for High-Purity Hydrogen for PEM Fuel Cell

چکیده مقاله

Fuel cell based modular power generation can be achieved by miniaturization and process intensification of equipments in the process. Fuel cells require hydrogen rich gas which can be generated through reforming and water-gas shift (WGS) reaction. The goal of this work is to understand the effect of the relative values of membrane permselectivity, permeation flux and investigation of a water-gas shift membrane reactor via two operating temperature (high temperature-low temperature). This was achieved by simulating the operation of an isothermal tube–shell reactor. The water-gas shift reactor being kinetically limited occupies more volume to achieve the required CO conversion. The model of the composite Pd-membrane includes the presence of defects in the palladium film and a multilayered support, while in the WGS model kinetics of the reaction is considered. Membrane model has been first validated by comparison with permeation measurements, in the 250-410 °C temperature range, of a Pd-membranes 20μm thick. The influence of reaction pressure and GHSV (gas hourly space velocity), both varied from 7.0 to 11.0 bar and from 3450 to 14,000 h-1, respectively, was studied. Moreover, various steam to carbon feed molar ratio and mixtures at different feed concentration were supplied to the MR