Effect Of Perovskite On The Quality Of Vanadium-Titanium Sinter

Perovskite exists in vanadium-titanium sinter,but perovskite is brittle and has weak bonding effect,The liquid phase bonding is destroyed,the crack expansion is aggravated seriously,and the metallurgical properties of sinter are obviously reduced.It is of great significance to improve the quality of vanadium and titanium sinter to study and find out the methods to control the formation of perovskite.However,the research on the formation conditions and metallogenic mechanism of perovskite is still lack of systematization and completeness.Therefore,the mineralization process of perovskite and the mechanism of its influence on the quality of vanadium titanium sinter were systematically studied in combination with the current situation and technology of improving the quality of in-situ sinter of Chenggang.Through the study on the mineral phase structure and metallurgical properties of on-site vanadium titanium sinter,the internal relationship between the characteristics of perovskite and the quality of vanadium titanium sinter is clarified,and by studying the difference of mineral phase structure before and after the reduction of on-site vanadium titanium sinter without spraying Ca Cl₂ and spraying Ca Cl₂,explores the spray Ca Cl₂improve perovskite of vanadium titanium sinter mechanism of adverse effects.The results show that Ca Cl₂ can hinder the contact between the reducing gas and the internal material of vanadium titanium sinter,hinder the crack propagation caused by perovskite,and maintain the corrosion structure with calcium ferrite as the main bonding phase.However,due to Ca Cl₂ corrosion equipment and many other problems,it is still necessary to further explore the mineralization process and influence mechanism of perovskite,in order to find other more ideal means to improve the quality of vanadium titanium sinter.The mineralization process and influence mechanism of perovskite were investigated by micro-sintering experiments with different basicity,TiO₂ content and temperature gradient.The results show that,compared with the sinter with the same TiO₂content,the content of perovskite in the sinter with the basicity of 2.5 is lower than that in the sinter with the basicity of 2.0,the content of calcium ferrite is increased,the interleavings and erosion structures are more,the porosity is reduced,the cracks are reduced,and the low temperature reduction degradation performance RDI_+3.15 is better.With the increase of TiO₂(4%-20%),the content of perovskite increased obviously and the particle size gradually increased,while the content of calcium ferrite increased at first and then decreased rapidly.The interlacing corrosion and corrosion structure of sinter gradually decreased and changed to granular structure and porphyry structure,and the low temperature reduction pulverization performance gradually deteriorated.The experimental results of different temperature gradient show that in the heating stage,the perovskite begins to form from 1280?to 1320?,and at this time,Ti element migrates from the liquid melt to the perovskite.With the increase of temperature,the content of perovskite increases and becomes the main Ti-bearing mineral.As the temperature increases from 1280?to 1400?,the content of calcium ferrite decreases.In the cooling stage,the content of calcium ferrite increases,indicating that the suitable sintering temperature of vanadium titanium magnetite concentrate is about 1280?.The experimental results provide a theoretical basis for improving the metallurgical properties of vanadium-titanium sinter,ensuring the smooth running of blast furnace and the reasonable optimization of sintering batching scheme.Figure 57;Table 13;Reference 69...