Influence of End-point Temperature Control on Dephosphorization for 100t Top and Bottom Combined Blown Converter Process

In order to address the dephosphorization problem of converter at the condition of high temperature,based on a 100 t converter dephosphorization experiments,the effect of end-point temperature control in converter on dephosphorization and measures that increase the dephosphorization capacity of converter with high tapping temperature had been studied in this paper. It is found out that with the increase of temperature,the phosphorus distribution ratio of slag/metal decreases,the dephosphorization capability of slag degrades and the liquid steel phosphorus content increases. Low temperature is an essential requirement for deep dephosphorization of converter. When the tapping temperature is lower than 1 620 ℃,it can realize tapping with liquid steel phosphorus content less than 0.01% even at~3.0 of the slag basicity. Increasing slag basicity leads to high absorption of phosphorus,while reducing P₂O₅ content in slag causes the increase of phosphate capacity of slag,and increasing FeO content in slag oxidizing atmosphere of converter bath increased. All these three measures can reduce the negative effect of high tapping temperature on dephosphorization.