Vacuum pressure swing adsorption for producing fuel cell grade hydrogen from IGCC

Abstract

In this work, a vacuum pressure swing adsorption (VPSA) process was developed for the fuel cell grade hydrogen purification from H2-rich syngas of an integrated gasification combined cycle (IGCC) plants, where activated carbon, 5 A zeolite, and Cu(I)AC were used as adsorbents. Two kinds of cycle configurations were proposed and evaluated to achieve a higher process performance based on ten bed VPSA process. Meanwhile, the effects of key operating parameters on the performance of the VPSA process with different cycle configurations were investigated. The results demonstrated that the impact of argon content in the feed gas on the process performance was significant, and the hydrogen purity in the light product stream would decrease from 99.9902% to 99.9119% when the argon content in feed gas varied from 1000 ppm to 10,000 ppm. Moreover, the cycle configuration 2 of VPSA process with a receive purge step achieves much better process performances compared with the cycle configuration 1 of VPSA process just with a blowdown step and vacuum step. Although the energy consumption of cycle configuration 2 is approximately 2–3 times that of cycle configuration 1, it's close to 90% hydrogen recovery and high productivity make it more competitive.