CFD simulation of an O2/N2 separation process using an industrial PIHF membrane module for N2 enrichment

•A new 3D mathematical model is developed for air separation based on an industrial polyimide hollow fiber membrane module aiming to N2 enrichment.•Good agreement was observed between the real operation data and model results so the new 3D model was validated.•Increasing the intensity of the feed flow has a negative effect on the N2 enrichment percentage as the main goal in this process.•The phenomenon of concentration polarization shows more intensity with the increase in the membrane length.•Feed pressure enhancement and augmentation of sweep gas flow rate shows a positive effect on N2 enrichment.