Modeling and Simulation of a Bubbling SO2 Absorber with Granular Limestone Slurry and an Organic Acid Additive

The absorption of SO 2 into limestone slurry containing suspended reactive particles was performed in a bubble reactor with continuous feeding of both gas and liquid phases at a constant pH and high temperature (50°C). An absorption model with a reaction plane based on the film model was developed. The effect of limestone particle size, concentration, acetic acid additives, and inlet SO 2 concentration on the concentration distribution of chemical species in the liquid film and SO 2 absorption rate were simulated. Increasing the concentration of limestone slurry, adding acetic acid additives into the system or decreasing the limestone particle size or inlet SO 2 concentration caused the reaction plane in the liquid film to shift towards the gas-liquid interface. Model and experimental results were compared, and it was shown that the model fits the experimental data well.