FEASIBILITY STUDY OF THE APPLICATION OF MEMBRANE SEPARATION IN CO2 REMOVAL FROM FLUE-GASES

The application of membrane separation in CO2 removal from flue gases was investigated by computation with three types of operation modes, i.e., conventional single-stage permeator (SSP), continuous membrane columun (CMC) and simple two-stage cascade (TSC). To recover 60% of CO2 With 90% in purity, membrane selectivity of 210 was necessary for SSP, 70 for CMC with a recycle ratio (RR) of 2, 44 for CMC (RR=3) and 24 for TSC, respectively. TSC mode consumed the largest power, equivalent to 15.6% of the power generated from petroleum, whereas SSP mode consumed 36%, that of TSC. Total energy consumption combined with liquefaction was estimated as 28.0 for TSC, 26.9 for CMC (RR=3), 22.9 for CMC (RR=2), and 14.9 kWh.kmol-1-CO2 recovered for SSP, respectively. The three types of membrane separation modes combined with liquefaction have an economical advantage in operation energy compared to the combined process of chemical absorption and liquefaction.