Effect of Slag Basicity on Dephosphorization at Lower Basicity and Lower Temperature Based on Industrial Experiments and Ion-Molecular Coexistence Theory

Influence of Temperature on Dephosphorization at Lower Basicity and Lower Temperature Based on Industrial Experiments and IMCT

“…In recent years, the ion molecule coexistence theory (IMCT) has been successfully applied to the thermodynamic calculation of dephosphorization process in converter. [22][23][24][25][26][27][28][29][30] Yang et al 23,24) established CaO-SiO 2 -MgO-MnO-FeO-Fe 2 O 3 -Al 2 O 3 -P 2 O 5 slag thermodynamic prediction models of phosphorus distribution ratio IMCT-L P and phosphorus capacity IMCT-C PO4 3−, respectively. The results showed that the IMCT thermodynamic model can not only accurately predict the phosphorus distribution ratio and phosphorus capacity of steelmaking slag, but also accurately predict the phosphorus distribution ratio and phosphorus capacity of each phosphorus containing component in slag, without introducing new fitting parameters.…”

“…The mass action concentrations of P 2 O 5 containing components and calcium silicate were further processed mathematically, so that the enrichment contribution ratio of calcium silicate R Ci and the enrichment degree of P 2 O 5 containing components R C P i j − were obtained. [28][29][30] Xie et al 28) clarified the effects of basicity, FeO content, FeO/Fe 2 O 3 and P 2 O 5 content on the phosphorus enrichment contribution ratio of four kinds of calcium silicate in multiphase slag through R Ci at 1 350°C. Li et al 29) discussed the enrichment behavior of phosphorus in steelmaking slag of CaO-FeO-Fe 2 O 3 -SiO 2 -MgO at 1 450-1 600°C.…”

“…The morphology, area and compositions of the P-rich phase were observed and analyzed, and the coefficient n of nC 2 S-C 3 P in P-rich phase was determined in the different temperatures. Using our developed IMCT thermodynamic model, 30) the effect of DET on the mass action concentration of calcium silicate and calcium phosphate, the phosphorus enrichment degree in dephosphorization slag and the phosphorus enrichment capacity of calcium silicate was studied, which was further compared with the analysis results of slag phases.…”

“…The details of the basic operation parameters and the amount of auxiliary materials used in the industrial experiment for NDSP were described in our previous paper. 30) The initial compositions of hot metals which are pre-desulfurized are shown in Table 1, and the heat numbers are T1345-T1450, which correspond to the end temperatures of dephosphorization as shown in Table 2.…”

“…The sampling and analysis methods of dephosphorization slag samples were also described in details in our previous papers. 30,31) The chemical compositions of hot metal and dephosphorization slags at different dephosphorization endpoint temperatures are shown in Table 2. The dephosphorization slag basicity is calculated by binary basicity (B), which is expressed as Eq.…”