Computational Study of Flash Calcination of Lime Mud from Pulp and Paper Mill Process

High Resolution Image Download MS PowerPoint Slide Calcination, where CaCO 3 is thermally decomposed to CaO and CO 2, is one of the most important chemical reactions. In this work, a CFD model is developed to investigate the flash calcination behavior of lime mud under various temperatures and gas atmospheres. Simulation results are compared with experimental data obtained from a pilot-scale flash calcination experimental campaign conducted in a drop tube furnace at the RISE site in Piteå. The simulated flash calcination temperature ranges from 700 to 1350 °C, with 50 °C increments, under different atmospheric conditions: 100% N 2, CO 2, and H 2 O vapor, as well as a 50/50 mixture of CO 2 and H 2 O vapor. The comparison shows overall good agreement between simulations and experiments, with most flash calcination thresholds accurately captured, particularly in cases involving CO 2 -containing atmospheres. The particle residence time, temperature, and the presence of CO 2 and H 2 O vapor were identified as the most influential parameters affecting flash calcination conversion and the evolution of the specific surface area.