Performance Evaluation of Accelerated Carbonation of Basic Oxygen Furnace Slag Via a Rotating Packed Bed: Modeling, Analysis and Maximization

Performance of accelerated carbonation by basic oxygen furnace slag (BOFS) in a rotating packed bed (RPB) was evaluated in this investigation.  The design of experiments (DOE) was introduced to evaluate the effect of different operating parameters including reaction time , particle size of BOFS , temperature , liquid-to-solid (L/S) ratio , and rotating speed on carbonation conversion of BOFS.  A quadratic response surface was established statistically to yield maximum carbonation conversion based on experimental data.  In addition , both the fresh and carbonated BOFS were characterized by the thermogravimetry and differential scanning calorimetry (TG/DSC) , X-ray diffraction (XRD) , and scanning electron microscopy equipped with X-ray energy dispersive spectroscopy (SEM-XEDS) to confirm the results of accelerated carbonation of BOFS in an RPB.  Furthermore , by combining the process chemistry , reaction kinetics , and mass transfer , a prediction model for carbonation of BOFS within an RPB , with an error less than 10% , was well-developed.  The enhancement factors for mass transfer coefficient in case of carbonation of BOFS within an RPB were determined accordingly.  In comparison with the developed model and the RSM results , a standard operation procedure (SOP) was proposed for maximizing the carbonation conversion of BOFS.  It was thus concluded that the accelerated carbonation of BOFS using an RPB is a promising process for CO2 capture due to its higher carbonation conversion achieving in a short reaction time.