A novel on-site SMR process integrated with a hollow fiber membrane module for efficient blue hydrogen production: Modeling, validation, and techno-economic analysis

Steam methane reforming (SMR) is widely used in the hydrogen production industry; however, a significant amount of CO2 is released during this process. Several efforts have been made to produce low-CO2 hydrogen (blue hydrogen) via SMR; however, the proposed solutions are not applicable to small-scale plants. Therefore, this study proposes an on-site SMR process combined with a hollow fiber membrane module (HFMM) for CO2 capture in small-scale plants. First, mathematical models for the on-site SMR process and HFMMs were developed, and their accuracy was validated with real-world data. Second, we designed and implemented the SMR-HFMM model based on different operating conditions and gas compositions at three potential CO2 capture locations (dry syngas, PSA tail gas, and flue gas). The CO2 capture performances at these three locations were compared using five performance indicators: stage cut, separation factor, CO2 recovery rate, permeate composition, and retentate composition. Finally, to evaluate the integrated processes for each CO2 capture location, feasible ranges of the number of HFMMs and the levelized cost of hydrogen (LCOH) were calculated. In the case of CO2 captured in dry syngas, the number of HFMMs required to achieve a CO2 purity of over 90% was calculated to be 10-25. Furthermore, despite additional HFMM installation, the LCOH was 0.8%-1.5% lower than that of the conventional on-site SMR process that is 7.07-7.13 USD/kgH2. The proposed integrated SMR-HFMM process is a potential solution to the problem of CO2 emissions in on-site SMR processes with a lower LCOH. Therefore, the findings of this study could be of significant importance in improving the environmental sustainability of hydrogen production in small-scale plants.