A comparative study was made of the reduction kinetics for high temperature smelting of vadium-titanium-containing magnetite,together with Hainan iron ore,using iron bath method.Three peaks were revealed on the reduct...A comparative study was made of the reduction kinetics for high temperature smelting of vadium-titanium-containing magnetite,together with Hainan iron ore,using iron bath method.Three peaks were revealed on the reduction rate curves for the magnetite,while one peak only for Hainan ore.Under the same conditions,the smelting reduction rate of the magnetite was found to be lower than that of Hainan ore.The rate increases evidently with the increase of the bath volume.The expressions of smelting reduction rate were suggested for the reduction with and without iron bath respectively.展开更多
To achieve the high-efficiency utilization of vanadium-titanium magnetite( VTM),reduction experiments were conducted to determine the carbothermic reduction mechanism of VTM. Effects of volatile matter,temperature,t...To achieve the high-efficiency utilization of vanadium-titanium magnetite( VTM),reduction experiments were conducted to determine the carbothermic reduction mechanism of VTM. Effects of volatile matter,temperature,time,and carbon ratio( molar ratio of fixed carbon in coal to oxygen in iron oxides of VTM) on reduction degree were investigated.Results show that reduction degree increases with increasing volatile matter in coal,temperature,time,and carbon ratio.Phase transformation,microstructure,and reduction path were analyzed by X-ray diffraction,scanning electron microscopy,energy-dispersive X-ray spectroscopy,and Fact Sage 6. 0. The thermoravimetry-differential scanning calorimetry-quadrupole mass spectrometer method was used for kinetic analysis of the main reduction process. Results indicate that the kinetic mechanism follows the principle of random nucleation and growth( n = 4),and the activation energy values at 600-900 and 900-1 350 ℃ are 88. 7 and 295. 5 kJ / mol,respectively.展开更多
文摘A comparative study was made of the reduction kinetics for high temperature smelting of vadium-titanium-containing magnetite,together with Hainan iron ore,using iron bath method.Three peaks were revealed on the reduction rate curves for the magnetite,while one peak only for Hainan ore.Under the same conditions,the smelting reduction rate of the magnetite was found to be lower than that of Hainan ore.The rate increases evidently with the increase of the bath volume.The expressions of smelting reduction rate were suggested for the reduction with and without iron bath respectively.
基金Item Sponsored by National High-tech Research and Development Project of China(2012AA062302)Major Program of National Natural Science Foundation of China(51090384)Fundamental Research Funds for the Central Universities of China(N130602003)
文摘To achieve the high-efficiency utilization of vanadium-titanium magnetite( VTM),reduction experiments were conducted to determine the carbothermic reduction mechanism of VTM. Effects of volatile matter,temperature,time,and carbon ratio( molar ratio of fixed carbon in coal to oxygen in iron oxides of VTM) on reduction degree were investigated.Results show that reduction degree increases with increasing volatile matter in coal,temperature,time,and carbon ratio.Phase transformation,microstructure,and reduction path were analyzed by X-ray diffraction,scanning electron microscopy,energy-dispersive X-ray spectroscopy,and Fact Sage 6. 0. The thermoravimetry-differential scanning calorimetry-quadrupole mass spectrometer method was used for kinetic analysis of the main reduction process. Results indicate that the kinetic mechanism follows the principle of random nucleation and growth( n = 4),and the activation energy values at 600-900 and 900-1 350 ℃ are 88. 7 and 295. 5 kJ / mol,respectively.