Crystallization kinetics of barium carbonate crystals in a lab-scale bubble-column scrubber

•Crystallization kinetic data of BaCO3 can be determined by the moments method.•The crystallization phenomena were found to be close to an MSMPR crystallizer.•The significant factors can be found in this study for future application.•Crystal sizes can be determined using the size limited theory found in here.•Capture and reuse of CO2 can be found to be feasible in this work.

The crystallization kinetics of barium carbonate crystals in the absorption of CO2 gas and reactive crystallization with barium chloride solution within pH range 12–13 was explored in a continuous lab-scale bubble-column scrubber under a constant pH environment. In considering the agglomeration of crystals, a population balance model with well mixed scrubber was proposed to determine the crystallization kinetic data by simultaneously including nucleation rate, agglomeration kernel and growth rate, using the first three moments. Investigation parameters focused on the pH of the solution, liquid concentration, liquid flow rate, gas concentration and gas flow rate. The effect of these parameters on the crystallization kinetics was explored. Herein, liquid concentration and liquid flow rate were found to be the dominant factors significantly influencing both nucleation rate and agglomeration kernel, while the pH of the solution had a moderate influence. Correlation expressions of the kinetic data were also discovered and analyzed further. Evidence indicated that particle size was limited by the nucleation rate, agglomeration kernel and mean residence time.