Bench Scale Testing of Next Generation Hollow Fiber Membrane Modules

Air Liquide (AL) is developing a next generation polyimide membrane material (PI-2) for application in our cold membrane hybrid process for CO₂ capture. Combining the cold membrane operation with an integrated CO₂ compression and purification unit significantly reduces the overall cost of CO₂ capture. The current work is aimed at developing the PI-2 material to a commercial scale, then validating its performance under real flue gas conditions.

Previous work (including grants DE-FE0004278 and DE-FE0013163) showed promising results for the cold membrane hybrid process utilizing the commercial available AL membrane bundles (PI-1 material). The Levelized Cost of Electricity (LCOE) for 90% CO₂ capture from a 550 MWe net coal power plant was projected to increase by 48 – 53%. The cold membrane technology was demonstrated at the National Carbon Capture Center with a 0.3 MWe field-test unit incorporating two 12” OD PI-1 commercial membrane bundles. That system exceeded its performance targets with stable membrane operation for over 500 hours. Finally, the new PI-2 membrane fiber was spun at lab scale and showed significant performance improvements: up to 10 times the CO₂ permeance and similar CO₂/N₂ selectivity as the existing commercial fiber (3 – 5 times the potential productivity per bundle).

The current project seeks to develop this next generation PI-2 material to a technology readiness level of 5 via manufacturing scale-up and testing with 300 - 1,000 Nm³/h of real flue gas, 0.1 - 0.3 MWe equivalents. Air Liquide manufacturing methodology will be applied to fabricate prototype membrane modules. Once the manufacturing methods prove reliable and performance is demonstrated in line with expectation, commercial scale bundles will be fabricated. Those commercial scale bundles will be performance tested with real flue gas at the National Carbon Capture Center. Finally, simulation studies of novel hybrid processes have begun that take advantage of the next generation fiber performance. The advantages and drawbacks of several arrangements will be discussed.

The current development work is supported by the Department of Energy National Energy Technology Laboratory under Award Number DE-FE0026422 (J. Figueroa, Program Manager).