The activity of CaO and LaOin the liquid ternary slay CaO-SiO-LaOhas been de-termined by equilibrating Sn with the slag phase in a graphite crucible under l arm of CO at1600C.The experimental results ,showed that the ...The activity of CaO and LaOin the liquid ternary slay CaO-SiO-LaOhas been de-termined by equilibrating Sn with the slag phase in a graphite crucible under l arm of CO at1600C.The experimental results ,showed that the activity of CaO and LaOchanges slowlywhile the ratio of mole fraction.x/x,is less than unit.hut varies sharply while the ra-rio increases from 1 to 1.2.In addition,by equilibrating Sn with the binary slagBO-LaOsaturated witlt solid LaOat three different temperatures,the relation betweenIgγ~0 and I/T is determined as follows:Igγ~0=-20400/T+11.37(1500-1600C)A random network model of molten silicate structure was applied to CaO-SiO-La2O.It was found that the experimentally determined activity-composition curve of CaO arequalitatively reproduced by the curves calculated with the model,but the curves of LaOareconsiderahly different from the calculated ones.It implies that the model used is over-simpli-fied and that the difference in interaction energy between the metal cations of different valenceand silicate anions should be considered.展开更多
The rate of reducing Fet O in CaO-SiO2-Al2O3-Fet O slags with carbon saturated in molten iron has been determined in a graphite crucible in the temperature range of 1673-1773K. The effects of temperature, slag basicit...The rate of reducing Fet O in CaO-SiO2-Al2O3-Fet O slags with carbon saturated in molten iron has been determined in a graphite crucible in the temperature range of 1673-1773K. The effects of temperature, slag basicity and FetO content on the reduction rate have also been discussed. Test results show that the reduction rate increases with increasing temperature or FEtO concentration in slags, and the reduction rate has a parabolic relation with the simple basicity or optical basicity of slag, the maximum reduction rate being observed at around CaO/SiO2=1.5 of molten slags. The reduction reaction order is 1. 73 or 1.80, and the reduction activation energy is 299.9 or 295.9 kJ/mol in regard to Fet O weight content or Fet O activity calculated by using regular solution model, respectively. The reduction rate of CaO-SiO2-Al2 O3-Fet O slags with carbon saturated in molten iron is in the range of 0.32-3.48 mol-O/cm2·s.展开更多
A thermochemical model based on the ion and molecule coexistence theory(IMCT)was developed to calculate thermodynamic data in the CaO-SiO_(2)-Al_(2)O_(3) slag system,considering the influential role of oxide activitie...A thermochemical model based on the ion and molecule coexistence theory(IMCT)was developed to calculate thermodynamic data in the CaO-SiO_(2)-Al_(2)O_(3) slag system,considering the influential role of oxide activities on the thermodynamic properties of slags.Using this model,iso-activity contours were obtained for oxide components CaO,SiO_(2) and Al2O3 in this system at temperatures of 1,873 K and 1,773 K.When compared with the IMCT model,it is found that the predicted activities of oxide components in the CaO-SiO_(2)-Al_(2)O_(3) system using the model developed in this study better matches experimental data from literature in terms of both trend and numerical value.Therefore,the model developed in this study can serve as a robust modeling tool for metallurgical processes,and the thermodynamic data predicted by this new model can be used to improve the metallurgical technology.展开更多
文摘The activity of CaO and LaOin the liquid ternary slay CaO-SiO-LaOhas been de-termined by equilibrating Sn with the slag phase in a graphite crucible under l arm of CO at1600C.The experimental results ,showed that the activity of CaO and LaOchanges slowlywhile the ratio of mole fraction.x/x,is less than unit.hut varies sharply while the ra-rio increases from 1 to 1.2.In addition,by equilibrating Sn with the binary slagBO-LaOsaturated witlt solid LaOat three different temperatures,the relation betweenIgγ~0 and I/T is determined as follows:Igγ~0=-20400/T+11.37(1500-1600C)A random network model of molten silicate structure was applied to CaO-SiO-La2O.It was found that the experimentally determined activity-composition curve of CaO arequalitatively reproduced by the curves calculated with the model,but the curves of LaOareconsiderahly different from the calculated ones.It implies that the model used is over-simpli-fied and that the difference in interaction energy between the metal cations of different valenceand silicate anions should be considered.
文摘The rate of reducing Fet O in CaO-SiO2-Al2O3-Fet O slags with carbon saturated in molten iron has been determined in a graphite crucible in the temperature range of 1673-1773K. The effects of temperature, slag basicity and FetO content on the reduction rate have also been discussed. Test results show that the reduction rate increases with increasing temperature or FEtO concentration in slags, and the reduction rate has a parabolic relation with the simple basicity or optical basicity of slag, the maximum reduction rate being observed at around CaO/SiO2=1.5 of molten slags. The reduction reaction order is 1. 73 or 1.80, and the reduction activation energy is 299.9 or 295.9 kJ/mol in regard to Fet O weight content or Fet O activity calculated by using regular solution model, respectively. The reduction rate of CaO-SiO2-Al2 O3-Fet O slags with carbon saturated in molten iron is in the range of 0.32-3.48 mol-O/cm2·s.
基金This work was financially supported by the National Natural Science Foundation of China(NSFC 52175352).
文摘A thermochemical model based on the ion and molecule coexistence theory(IMCT)was developed to calculate thermodynamic data in the CaO-SiO_(2)-Al_(2)O_(3) slag system,considering the influential role of oxide activities on the thermodynamic properties of slags.Using this model,iso-activity contours were obtained for oxide components CaO,SiO_(2) and Al2O3 in this system at temperatures of 1,873 K and 1,773 K.When compared with the IMCT model,it is found that the predicted activities of oxide components in the CaO-SiO_(2)-Al_(2)O_(3) system using the model developed in this study better matches experimental data from literature in terms of both trend and numerical value.Therefore,the model developed in this study can serve as a robust modeling tool for metallurgical processes,and the thermodynamic data predicted by this new model can be used to improve the metallurgical technology.
