Bench Scale Testing of Next Generation Hollow Fiber Membrane Modules

Air Liquide is developing a next generation polyimide membrane material (PI-2) for application in our cold membrane hybrid process for CO₂ capture. Combining the PI-2 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 showed promising results for the cold membrane hybrid process utilizing the commercially available Air Liquide PI-1 membrane bundles. The cold membrane technology was demonstrated at the National Carbon Capture Center (NCCC) with a 0.3 MWe field-test unit incorporating 12” diameter PI-1 commercial bundle. The cost of 90% CO₂ capture from a 550 MWe net coal power plant was estimated to be between 40 and $45/tonne. The novel PI-2 membrane was tested at a smaller scale (1” modules) and exhibited up to 10 times the CO₂ permeance and similar CO₂/N₂ selectivity as the PI-1 membrane. This corresponds to a potential cost reduction of $3/tonne for CO₂ capture.

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 600 - 1,000 Nm³/h of real flue gas, 0.2 - 0.3 MWe equivalents. 6” diameter commercial membrane bundles have been fabricated and tested at NCCC. These bundles met the project success criteria with a productivity of over 640 Nm³/hr and permeate purity in excess of 60%, at 90% CO₂ recovery. An advanced bundle formation technique, which further lowers the bundle cost and CO₂ capture cost, is also being developed under the scope of this project. Further manufacturing scale-up is underway to verify the technique. A final techno-economic analysis (TEA) for a 550 MWe net power plant has been initiated.