Kinetic Mechanism and Process Optimization of Hot Metal Desulfurization Pretreatment

A 1/5 scale water model simulation was used to study the kinetic mechanism for 300 t mechanical stirring desulfurization station, factors including rotating speed, immersion depth and size of impellers were investigated. The results show the dispersion behavior of desulfurizer can be divided into three stages, (1) the entrainment depth of desulfurizer increases with the rotating speed increasing, (2) the entrainment depth of the desulfurizer remains unchanged, (3) the desulfurizer is thrown out into the water from impeller blades. For the reason that the desulfurizer is sticky to the top surface and the middle of impeller blades, which will cause the shortening of the impeller life, the optimum rotating speed is the minimum rotating rate that the desulfurizer reaches the upper surface of impellers, which is related with immersion depth of impellers compared with the bath level and the length of impellers compared with the diameter of the ladle. After the application of a larger impeller, with 14.0% impeller life longer than before and the sulfur element is removed to 0.0006% on average.