MODELLING AND EXPERIMENTAL STUDIES OF DIFFUSIVITY OF SULFUR AND ITS RELEVANCE IN OBSERVING SURFACE OSCILLATIONS AT THE SLAG METAL INTERFACE THROUGH X-RAY IMAGING

摘要

A generic model was conceived for predicting the diffusion coefficient of species in slag. The diffusion coefficient of sulfur in CaO-Al_2O_3-SiO_2 slag with low silica was measured using a combinational technique of the generic model and experiments. The uniqueness of the experiments was in the method of collecting samples. Another milestone was that the diffusion coefficient of sulfur in the slag was obtained through the sulfur levels in the metal (silver). Later the order of magnitude of the diffusion coefficient of sulfur in slag was used to estimate the time required for sulfur to reach the slag-metal interface of an iron drop immersed in CaO-Al_2O_3-FeO-SiO_2 slag. This estimated time for arrival of sulfur at the interface was comparable to the actual observation. The current paper describes the challenges in measuring the diffusion coefficient of sulfur. It also describes the time estimates calculated based on the X-ray image for sulfur to reach the slag-metal interface.