The property of hydrogen separation from CO2 mixture using Pd-based membranes for carbon capture and storage (CCS)

This study investigates the module configuration for upscaling CO2 capture capacity to a bench-scale in hydrogen selective Pd-based composite membranes. In order to confirm effective upscaling, four plate-type membranes of two inch diameter were stacked in a newly designed plate-and-frame type module, reaching a total membrane surface area of 6.64 × 10−3 m2 (66.4 cm2). A pure gas test carried out using H2 and He confirmed that there were no effects of module configuration in gas permeation behavior, indicating that the upscale of the separation capacity by numbering-up of membranes using our module design was successful. The CO2 enrichment test was conducted using a 40%CO2 + 60%H2 mixture (i.e. a similar composition for the coal gasifier after both the shift reaction and H2O removal), under high feed pressure and flow rate, i.e. 600–2100 kPa and 0.48–0.72 N m3 h−1. The mixture gas test confirmed that the bench-scale membrane module could enrich 40% of the CO2 at a feed flow rate of 0.48 N m3 h−1 up to 93% with a hydrogen recovery ratio of >90% at 673 K and a total feed pressure of 2100 kPa, i.e. ∼4 times CO2 enrichment capacity of one membrane.