Utilizing solid polyamines in a rotary bed to capture CO2 in an energy and cost-efficient manner

Abstract

Solid polyamines were employed as promising adsorbents to reversibly capture CO₂ from humidity flue gas and release it at a lower regeneration temperature (348 K) with limited volatility and degradation of amine. Furthermore, it is extremely important to decrease the process costs and energy consumption by exploring an alternative CO₂ capture process and exploring the corresponding parameters for further scale-up and industrial application. Therefore, a temperature vacuum swing adsorption process was optimized for post-combustion CO₂ capture from wet flue gas by utilizing solid polyamine in a three-column fixed-bed and a rotary bed system; the process was then evaluated through mathematical modeling. CO₂ recovery, energy consumption, and CO₂ capture cost performance of the rotary bed resulted in significant improvements over those of the fixed-bed system. The optimized rotary bed process can save ∼21.76% on the total CO₂ capture cost as compared to the fixed-bed system, which is mainly attributed to improved CO₂ recovery and reduced adsorbents cost. The optimum performance indices for capturing 12% of the CO₂ from the humidity flue gas using a rotary bed in terms of energy consumption, CO₂ recovery, and CO₂ purity were 1.11 GJ per ton CO₂, 96.4%, and 99.6% respectively. These simulation results indicate that the rotary bed with temperature vacuum swing adsorption process could be a cost and energy-efficient post-combustion CO₂ capture technology.