(11a) Fabrication and Field Testing of Spiral-Wound Membrane Modules for CO2 Capture from Flue Gas

A spiral-wound membrane module, including a spiral-wound membrane element, Plexiglas fiber-reinforced plastic tube, and membrane housing with face compression “O” rings for effective seal of gases was developed. The spiral-wound membrane modules showed essentially no leakage and demonstrated an efficient gas separation. At a dry feed gas flow rate of less than 1000 sccm before humidification, a concentration polarization phenomenon was observed. Therefore, both dry feed and sweep gas flow rates each at 1000 sccm before humidification were used to evaluate the performances of the spiral-wound membrane modules at the typical flue gas temperature of 57^oC. The feed and sweep gas pressures were at 1.5 and 1 psig, respectively. The spiral-wound membrane modules showed similar performance results with a CO₂ permeance of greater than 800 GPU and a CO₂/N₂ selectivity of more than 140 when tested with either a simulated flue gas or an actual flue gas. The results were similar to the results obtained from the flat-sheet membrane used for the module fabrication. The pressure drops of the modules were less than 1.5 psi/m and met the requirements for CO₂ capture from flue gas. The performances of the modules revealed some unexpected issues during the field test using the actual flue gas at the National Carbon Capture Center in Wilsonville, Alabama, including the feed spacer indentations on the membrane selective layer and the leakage at glue lines. Improvement of the spiral-wound membrane module fabrication was made by using a smoother feed spacer and a longer glue curing time. The spiral-wound membrane module was scaled up to a 5 inches diameter to accommodate a membrane area of around 14000 cm². A suitable spacer was selected to accommodate a spiral-wound membrane module test with vacuum at the permeate side. The field test results of the modules have shown their good potential for the post-combustion CO₂ capture from coal-fired power plants.