Optimization of Pressure Swing Adsorption and Fractionated Vacuum Pressure Swing Adsorption Processes for CO₂ Capture

Abstract

This work focuses on the optimization of cyclic adsorption processes to improve the performance of CO 2 capture from flue gas, consisting of nitrogen and carbon dioxide. The adopted processes are the PSA (pressure swing adsorption) process and the FVPSA (fractionated vacuum pressure swing adsorption) process, modified from the FVSA (fractionated vacuum swing adsorption) process developed by Air Products and Chemicals, Inc. The system models are currently bench scale and adopt zeolite13X as an adsorbent. The high-temperature PSA is better for high purity of product (CO 2 ), and the high-temperature FVPSA is much better than the normal-temperature PSA processes. The main goal of this study is to improve the purity and recovery of carbon dioxide. The Langmuir isotherm parameters were calculated from experimental data taken at National Energy Technology Laboratory (Siriwardane, R.; NETL, DOE, 2004). Moreover, efficient optimization strategies are essential to compare these processes. To perform optimization work more efficiently, we modified the previous optimization method by Ko et al. (Ind. Eng. Chem. Res. 2003, 42, 339-348) in a manner similar to that by Jiang et al. (AIChE J. 2003, 49, 1140-1157. This allows us to obtain optimization results with more accurate cyclic steady states (CSSs), better convergence, and faster computation. As a result, optimal conditions at CSS are found for these systems.

High yield and high packing density porous carbon for unprecedented CO2 capture from the first attempt at activation of air-carbonized biomass

“…95,96 The removal of CO2 from flue gas streams may more efficiently be accomplished with solid state adsorbents such as activated carbons via either pressure swing adsorption (PSA) or vacuum swing adsorption (VSA) processes. 97,98 A typical PSA system may adsorb at a pressure of 6 bar and be recycled (i.e., desorb) at 1 bar, while for VSA systems, adsorption may occur at 1.5 bar and evacuation at ca. 0.05 bar.…”

Separation of Carbon Dioxide from Flue Gas Using Adsorption on Porous Solids

“…As proposed by Grande and Rodrigues (2008) for CO 2 adsorption, adsorbents with a greater adsorption capacity and higher heat of adsorption than the activated carbon honeycomb monolith should be used to achieve a product purity of greater than 16%. Although the CO 2 purity is lower than that is required to transport, the PSA cycle could be optimized in order to increase the CO 2 purity and recovery (Ko et al, 2005). Transport considerations limit the CO 2 purity > 95.5% to ensure a reasonable input of CO 2 compression power (Vinay & Handal, 2010).…”

“…PSA is a cyclical process of adsorption/desorption that occurs through pressure changes and can be very suitable for carbon dioxide separation from exhaust gases due to its easy application in a large temperature range. The most studies presents the CO 2 /N 2 separation using PSA process at room temperature, but it has been reported that is possible to obtain high purity CO 2 (~90%) at high temperature (Ko et al, 2005). Recently, Grande and Rodrigues (2008) reported that it is possible to recover around 89% of the CO 2 from a CO 2 /N 2 mixture using honeycomb monoliths of activated carbon through ESA.…”

Post-combustion CO2 capture with a commercial activated carbon: Comparison of different regeneration strategies

“…Within TSA technologies, the specific case in which the solid is heated by the Joule effect is commonly referred to as electric swing adsorption (ESA) [5,6]. The vast majority of studies dealing with CO 2 post-combustion capture by means of PSA or TSA technologies use zeolites as adsorbent [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Zeolite 13X is by far the adsorbent most extensively studied in CO 2 separation processes, due to its high selectivity to CO 2 [21].…”