The Separative Performance of Modules with Polymeric Membranes for a Hybrid Adsorptive/Membrane Process of CO2 Capture from Flue Gas

Abstract

Commercially available polymeric membrane materials may also show their potential for CO2 capture by the association of the membrane process with other separation techniques in a hybrid system. In the current study, PRISM PA1020/Air Products and UBE UMS-A5 modules with membrane formed of modified polysulfone and polyimide, respectively, were assessed as a second stage in the hybrid vacuum swing adsorption (VSA)–membrane process developed in our laboratory. For this purpose, the module permeances of CO2, N2, and O2 at different temperatures were determined, and the separation of CO2/N2 and CO2/N2/O2 mixtures was investigated in an experimental setup. An appropriate mathematical model was also developed and validated based on experimental data. It was found that both modules can provide CO2-rich gas of the purity of > 95% with virtually the same recovery (40.7−63.6% for maximum carbon dioxide content in permeate) when fed with pre-enriched effluent from the VSA unit. It was also found that this level of purity and recovery was reached at a low feed to permeate the pressure ratio (2−2.5) in both modules. In addition, both modules reveal stable separation performance, and thus, their applicability in a hybrid system depends on investment outlays and will be the subject of optimization investigations, which will be supported by the model presented and validated in this study.

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“…The modules were used in the experimental setup as supplied, and parameters used in the experiments were within the pressure and temperature ranges recommended by the manufacturers. The membrane area in these modules was 2.24 m 2 in the case of PRISM PA1020 [33,34] and 0.167 m 2 [35] in the case of UMS-A5. Other technical parameters of the modules were given in [29].…”

“…Permeance coefficients of pure CO 2 , N 2 and O 2 in both modules were determined experimentally in our previous studies [34,35]. In the case of pure methane, the permeance was determined experimentally at 295 K. For this purpose, the feed gas pressure was changed within the range of 0.12-0.72 MPa (a) and the corresponding permeate flow rate was measured.…”

“…Table 2. The permeance of methane, carbon dioxide, oxygen and nitrogen [34,35]. The permeance of all gases in UMS-A5 with the polyimide membrane is significantly higher than that in PRISM PA1020 with the polysulfone one.…”

“…More importantly, the ideal selectivity of CO2, O2 and N2 vs. methane was also visibly (2.4-2.8 times) higher in the Table 2. The permeance of methane, carbon dioxide, oxygen and nitrogen [34,35]. The permeance of all gases in UMS-A5 with the polyimide membrane is significantly higher than that in PRISM PA1020 with the polysulfone one.…”

“…The permeance of CO 2 , N 2 and O 2 presented in Table 2 concerns fresh, unused earlier modules and was used in a simulation study, discussed in Section 3.4. In the case of the experimental study discussed in Section 3.3, both modules have been used in other separations for a few years and their separation properties have changed [34]. In this case, current permeance coefficients of CO 2 were determined and used for the purpose of model validation, which were equal to 128.1 and 992.2 GPU in PRISM PA1020 and UMS-A5, respectively.…”