Effects of Typical Components on Physicochemical Properties of Refining Slag and Sulfur Migration Enhanced by Electric Field

Directional Sulfur Removal from Ladle Furnace Slag by Electric Field Strengthening Treatment

“…The substantial reduction of Mg 2+ and Ca 2+ content in the slag at 6 V led to the polymerization of the slag structure, resulting in an increase in viscosity and a decrease in conductivity. [ 16 ] Sulfur volatilization was also observed in the experiment, although sulfur was still dominated by migration. It is therefore established that stronger sealing of the experimental device lowers the volatilization of sulfur.…”

“…This is consistent with the previous conclusion regarding the electric field effect on sulfur migration in LFS with different CaO/Al 2 O 3 mass ratios. [ 16 ] The ion migration rate is the restricting factor of the high‐temperature slag–metal reaction, which is determined by the driving force and resistance. The external electric field applied to the slag–metal reaction creates a driving force that promotes S 2− migration from the slag to the anode (hot metal).…”

“…In order to ensure the uniformity of slag and reduce the experimental error, the slag components were mixed thoroughly in a stainless‐steel pot and then premelted in a graphite crucible by an induction furnace. Moreover, since X‐ray fluorescence (XRF) has shown in previous studies that the change in composition before and after premelted slag was insignificant, [ 16 ] the influence of component volatilization was disregarded in the present study. The composition of the steel used in the experiment is listed in Table 2 .…”

“…Because the MgO content in LFS was mainly concentrated between 4 and 14 wt%, [27,29,30] and MgO addition in the range of 4-8 wt% reduced the melting temperature and viscosity while excess MgO sharply deteriorated the slag melting property. [16] 4-12 wt% MgO was selected for comparative analysis.…”

“…The primary methods for removing sulfur from LFS include solid-state hightemperature oxidation, [13] solid-state hydrothermal leaching, [14] molten-state thermal oxidation, [15] and electric field strengthening. [16,17] However, in the first three methods previously listed, the existing forms of CaS and 11CaO-7A1 2 O 3 -CaS solid solutions hinder sulfur migration, wasting large amounts of cooling water and slag heat during the treatment process and causing secondary pollution by SO 2 . Based on the electrochemical reaction mechanism of the slag-metal interface, various voltages were applied to promote the directional migration of sulfur from the LFS to molten steel to accomplish slag recycling in secondary refining and reuse of hot metal for sulfur-containing steel production.…”