Integration of proton exchange membrane fuel cell stack with a methanol reformer the reformer design and testing

• Main Author: Miao, Bin
• Other Authors: Chan Siew Hwa
• Format: Final Year Project
• Language: English
• Published: 2015
• Subjects: DRNTU::Engineering::Mechanical engineering::Alternative, renewable energy sources
• Online Access: http://hdl.handle.net/10356/62056
• Institution: Nanyang Technological University

A methanol reformer is a device that produces hydrogen gas from methanol and water mixture. This process is called steam reforming of methanol. The purpose of this process is to provide pure hydrogen to fuel cell, especially in automobile applications, to generate electricity. The significance of this device is that it bypasses all the issues that hydrogen storage may encountered in automobile application, which are extreme low temperature and high pressure. This project fabricated a testing rig for steam reforming of methanol catalysts development. Firstly, a compact aluminum reformer with Ø52mm 150mm length was fabricated. The designed working temperature of the reformer is from 220°C to 300°C to test various catalysts performance. The reformer combined a Ø10mm 45mm steam vaporizer and a Ø10mm 45mm reformer into a single cylindrical unit. The vaporizer volume was occupied with porous alumina pellets to enhance vaporizing performance. The loading capacity of the reformer chamber is from 3 gram to 5 gram, which varies from catalysts density. Electrical heater simulated as methanol catalytic combustion heat source to start up the reforming and the reformer temperature stabilized in desired temperature within 30 minutes. Secondly, commercial CuO/ZnO/Al2O3 based catalyst was tested on the rig as reference. Parametric studies were carried out to test the effect of reforming temperature, fuel feed rate and water-fuel ratio on methanol conversion rate and H2 selectivity. Experimental results coincided with literatures that higher reforming temperature yield higher fuel conversion rate. Results showed average 83.54% methanol conversion rate with fuel feed rate 0.25 ml per minutes and reforming temperature 280°C. The drawback of higher reforming temperature CO concentration increased, which is not good for fuel cell catalyst. Gas analyzer showed CO concentration 908 to1180 particle per million in the production gas. CO concentration can be reduced by introduce higher water-fuel ratio and faster feed rate of the fuel.