The phase transformation and nucleation growth behavior of niobium mineral phase in Bayan Obo mine under high temperature melting state were studied.The effects of different temperature mechanism,basicity(CaO/SiO2)and slag modifiers such as NaF,CaF2 and P2 O5 on phase transformation and nucleation growth were emphatically investigated.The results show that the melting temperature above 1 400 ℃ and the crystallization temperature below 1 300 ℃ are the key to the phase conversion of high-grade niobium ore.Control alkalinity between 1.0 and 1.3 is beneficial to the formation of single high-grade niobium phase and the growth of grain.The addition of about 2％NaF or 2％-5％CaF2 can improve the grade of Nb2 O5 and grain coarsening of niobium-rich phase.Although P2O5 is conducive to the transformation of niobium into a single high-grade niobium mineral phase,excessive P2O5 will lead to sharp refinement of niobium phase grains.
关键词
矿相转化/晶粒生长/白云鄂博铌矿
Key words
mineral phase transformation/grain growth/bayan obo niobite
维普
万方数据