Advanced Modeling for Performance Optimization of CO2 Removal in Industrial Absorbers
The removal of carbon dioxide from reactor effluents and recycle streams, using absorption with chemical reaction technique, is of critical importance for many industrial operations. In this study, carbon dioxide produced by the reaction of ethylene and oxygen is removed with activated potassium carbonate using a boron-vanadium activated solution. Boron and vanadium are added to the hot carbonate system as boric acid and vandium pentoxide. Both the added components react with the potassium carbonate to form potassium borate and potassium vandate, respectively. The overhead cooled gas is then sent to the reaction system in ethylene oxide reactor. This research is focused on developing and applying simulation models to optimize the performance of an industrial CO2 removal absorber. The model consists of an extensive set of important reactions and considers the alignment between mass transfer and chemical kinetics. Mass transfer coefficient has been calculated from penetration theory and the chemical reaction in the liquid phase followed by instantaneous regime. The mathematical models, comprising coupled sets of non-linear differential and algebraic equations, were solved using our software package on the absorber. The impact of parameters such as inlet temperature of lean solution, hot feed location has been examined. The model has been used to calculate various flow, temperature and concentration profiles in the absorber. The model prediction was checked against the data from an industrial CO2 removal absorber. The integrated models, dynamically linking the ethylene oxide reactor, will be used to develop a control scheme to ensure optimized performance of the reactor.