Scale up of PEEK Hollow Fiber Membrane Contractor for Post Combustion CO2 Capture

Shiguang Li, 

Naomi B. Klinghoffer, James L. Aderhold, Howard S. Meyer, Yong Ding, and Benjamin Bikson, Gas Technology Institute

Poly(ether ether ketone) (PEEK) hollow fiber membrane modules were scaled up from 2 inch diameterand 16 inch long to 4 inch diameter and 58 inch long (a factor of 90 increase in membrane area) for CO₂ capture from flue gases using membrane contactor process, which combines advantageous features of both absorption and membrane processes. Field test of a 4-inch-diamter module with activated methyldiethanolamine (aMDEA) solvent demonstrated greater than 90% CO₂ removal. The mass transfer coefficient in the absorption step was 1.2 (sec)^-1, which is over an order of magnitude greater than that of conventional column contactors. The membrane module was further scaled up from 4 inch to 8 inch diameter (a factor 3 increase in membrane area). Single-gas permeation measurements indicated that 8-inch modules have an intrinsic CO₂ permeance as high as 2,150-2,670 GPU. One 8-inch-diameter module was tested in membrane contactor mode for CO₂ capture using a simulated flue gas. Carbon dioxide removal rate of 91.3% was achieved with a mass transfer coefficient of 1.5 (sec)^-1. Parametric tests indicated CO₂ flux and capture rate increased with increasing feed pressure, solvent flow velocity and solvent temperature. PEEK hollow fiber membrance contactor is effective in capturing CO₂ from low CO₂-concentration feeds, showing its high potential for natural gas flue gas CO₂ capture.