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

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 similar to 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.