Study on Phase Transformation and Nucleation Growth of Bayan Obo Niobium Ore
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.
mineral phase transformationgrain growthbayan obo niobite
万方数据
维普
