On Hydrodynamics of Dry Slag Granulation of LD/BOF Slag: Analytical Modeling

Experimental trial of dry granulation process has been widely performed to granulate blast furnace (BF) slag, in addition to, heat recovery from molten material. In this study, analytical formulation has been obtained for Dry Slag Granulation (DSG) process of Spinning Disc Atomizer (SDA) using literature survey and fundamental principles. An expression has been derived to obtain diameter of droplet formed, after granulation, by rotating disc method. In accordance with the three phases of the problem, i.e. thin viscous film formation, ligament formation, and droplet formation, mathematical models have been developed, separately, for each phase. Further, the obtained expression has been validated with established benchmarks. Further study has been also done on effects of rotating speed of disc and liquid flow-rate on diameter of droplets formed.