Formation of phosphate compound in multi-phase flux

摘要

Usually the CaO-based fluxes are used for hot metal dephosphorization. Since dephosphorization is operated at around 1573K, the solid CaO is not completely dissolved into the slag, which causes problems such as increase of slag volume and difficulty of slag recycling. It was observed that phosphorus condensed phase exists around solid CaO in the steelmaking slag. Therefore, it is expected to use the CaO based multi-phase flux to improve the refining performance. Much works have been done to clarify the reaction mechanism between solid CaO and molten slag.[1-3] However the behavior of phosphorus in the multi-phase flux is not fully understood yet. The present work focuses on the formation behavior of phosphate compound in multi-phase flux. Solid CaO or 2CaO·SiO2 was reacted with FeOx-CaO-SiO2-P2O5 slag at hot metal temperatures. The reaction behavior of phosphorus at the interface area was discussed.