460361 Batch Adsorber Analogs for Rapid Screening of Adsorbents for CO2 Capture
In this presentation, we extend the analysis of Maring and Webley by considering more complex cycles that include a three pressure-level operation; reflux, pressure equalization and light-product pressurization steps. This model is then used to predict the performance of 4 adsorbents, namely Zeolite 13X, Mg-MOF-74, UTSA-16, a type of coconut-shell derived activated carbon for post-combustion CO2 capture. The model assumes instantaneous equilibrium and isothermal operations. The impact of making these assumptions is first verified and then the batch-analog model is first validated by comparing the CO2 purity and recovery with that predicted by detailed models. By varying the operating conditions, the Pareto curve for maximizing purity and recovery is obtained and is comapred to the ones from detailed optimization . The results show that although the Pareto curves from the two modeling approaches are different, the relative ranking of adsorbents is indeed correct. Based on this observation, the effect of operating variables, e.g., intermediate and low pressure on the process performance is evaluated and the specific energy consumption for the different materials is calculated. Finally the by considering the Langmuir adsorption isotherm to represent both CO2 and N2, the effect of the isotherm parametrs, equilibirum constant, saturation capacity and heats of adsorption, on the process performance is mapped in the form of contour plots. These plots provide guidance for the development of new materials that could potentially show superior performance at the process scale.
 Rajagopalan, A. K.; Avila, A. M. & Rajendran, A.Do adsorbent screening metrics predict process performance? A process optimisation based study for post-combustion capture of CO2 Int. J. Greenhouse Gas Control, Elsevier, 2016, 46, 76-85.
 Maring, B. J. & Webley, P. A. A new simplified pressure/vacuum swing adsorption model for rapid adsorbent screening for CO2 capture applications Int. J. Greenh. Gas Con., Elsevier, 2013, 15, 16-31