The combustion of fossil fuels accounts for more than 85% of the world’s energy demand and causes significant carbon dioxide emissions, leading to severe climate change. Reducing these emissions is a key challenge that can be addressed through various strategies, such as carbon capture, storage, and utilization. Despite the development of technologies, CO$_2$ separation remains energy-intensive, primarily due to its chemical stability.
The aim of this master's thesis was to develop and evaluate a mathematical model of the CO$_2$ capture and mineralization process in bubble column reactor. Simulations and experimental results provided a deeper understanding of the kinetic and process parameters in both semi-batch and continuous operations. The mathematical model demonstrated good agreement with experimental data, despite minor deviations due to limitations in measurement accuracy and assumptions made during modelling. In semi-batch operation, we found that the high concentration of hydroxide ions in the initial phase accelerates the reaction, while the reaction rate decreases as the concentration drops in the second phase. Temperature played a significant role in the kinetics and equilibrium of the reaction, which enables system optimization. In continuous operation, the results showed that the absorption rate in the first phase becomes limited by the CO$_2$ feed rate, while increasing temperature affects the decomposition of sodium bicarbonate, altering the equilibrium and the CO$_2$ capture capacity. Experimental data confirmed the theoretical predictions, though deviations were linked to the influence of experimental conditions. The modelling proved useful for predicting system behaviour and optimizing process parameters, while future research could address challenges like crystallization and hydrodynamic conditions in the reactor.
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