The petrochemical industry has a significant demand for high-purity hydrogen. It primarily obtained from the H2 purification unit by using pressure swing adsorption (PSA) technology to recover H2 from medium-temperature shifting gas (MTSG). The the coupled wet CO2 separation-PSA process was introduced in this work, aiming to capture CO2 from MTSG while simultaneously increasing the H2 recovery rate. To enhance the desorption pressure of CO2 separation unit in the coupled process to facilitate the storage or utilization of the captured CO2, firstly, a rigorous thermodynamic study was carried out to provide a theoretical basis for the development of an improved CO2 solvent. Subsequently, a pilot-scale test was executed to validate the theoretical findings. Finally, the patented coupled process was implemented at an industrial scale for the first time. The results showed that the capacity of PSA unit for H2 purification increased from 6800 to 12,000 tons per year and the H2 recovery rate increased from 84.6 % to 93.6 %; the CO2 desorption pressure increased from about 0.03 MPa (traditional Benfield process) to 0.15 MPa, which reduced the energy consumption of CO2 compression, and the total average annual economic benefits increased by US $ 15.55 million.
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