Review of Polybed pressure swing adsorption for hydrogen purification

Hydrogen (H2) will play a key role in the future low-carbon energy society. The industrial production of hydrogen involves chemical reactions and purification steps. Pressure Swing Adsorption (PSA) is a versatile process able to produce ultrapure hydrogen (99.99+%) from various gas mixtures, resulting in the most widespread purification technology worldwide. In particular, the Polybed PSA system, having more than six beds and a complex cycle configuration, has proven to maximize H2 recovery and H2 throughput, exceeding 90% and 240 MMSCFD (265,000 Nm3 h−1) per single train, respectively. This paper systematically reviews the Polybed H2 PSA process for the first time, highlighting the latest technical advances and discussing its optimal integration in industrial clusters. A bespoke Polybed PSA process designed for simultaneous production of high-purity hydrogen and carbon dioxide (CO2) is also reviewed in light of the recent international directives aimed to reduce CO2 emissions and produce blue hydrogen.