CALCULATION MODEL FOR CONCENTRATION OF QUATERNARY SLAG SYSTEM SIO_2-CAO-AL_2O_3-FEO

摘要

According to the coexistence theory of slag structure, a calculation model of concentration of SiO_2-CaO-Al_2O_3-FeO of depleted copper slag was established. The model was used to calculate and analyze the effects of temperature(T), basicity(B) and Al_2O_3 content on the activity of FeO (N_(FeO))- The results show that temperature has little impact on N_(FeO). With the increase of basicity, N_(FeO) would increase slightly firstly, then increase sharply and finally decrease. CaO is easier to combine with SiO_2 than FeO to form calcium silicate, which replaces FeO in 2FeO SiO_2 and increases N_(FeO)- However, when the basicity is high than 2.0, CaO is not only to react with SiO_2, but also to combine with FeO to form calcium ferrate compounds to decrease N_(FeO)- In addition, the activity of FeO decreases with the increased content of Al_2O_3, because of the reaction between each other. The results can be used as a theoretical basis to guide the carbothermal reduction of copper slag.