【作者】 马莽原；

【导师】 白晨光；

【作者基本信息】 重庆大学 ， 冶金工程， 2010， 硕士

【摘要】 为了探索钒钛磁铁矿资源综合利用的新方法,本文在综述微波冶金的研究进展和钒钛磁铁矿资源利用的基础上,以攀钢钒钛磁铁矿为研究对象,采用微波碳热还原的方法,结合微波加热的基本理论和热力学计算,研究了微波场中钒钛磁铁矿的碳还原特性,得出以下主要结论:微波场中,温度影响还原反应进行的程度和还原产物。在还原温度为1300℃时,还原产物的主要物相是:金属铁、未还原的磁铁矿、钛铁矿和Fe₂TiO₅;在还原温度为1400℃时,还原产物的主要物相是:孔洞状的金属铁块、未还原的磁铁矿和FeTiO₃、MgTiO₃、Fe₂TiO₅和TiO₂、镁铝尖晶石（MgAl₂O₄）;在还原温度为1500℃时,还原产物出现渣铁分离,金属部分为铁钒合金,渣相部分主要物相是FeTiO₃、MgTiO₃、Fe₂TiO₅、Ti₃O₅、镁铝尖晶石（MgAl₂O₄）、FeO。配加一定量CaO的钒钛磁铁矿在微波碳还原过程中,因CaO与钛铁矿和钛铁晶石发生反应,可以促进这两种物质的分解,降低了钛铁矿和钛铁晶石中铁氧化物的还原难度;同时CaO与钒钛磁铁矿中的酸性氧化物发生反应,生成低熔点物质,有利于渣铁分离。但是过多的CaO反而会减弱钒钛磁铁矿的吸波性,渣铁分离的效果变差。实验结果表明:碱度为1.2、1.4、1.6的样品均比碱度为1.0的样品,还原效果好。钒钛磁铁矿中配加过量的碳,不仅为还原反应提供还原性气氛,而且过量的碳会覆盖在还原产物表面,使反应物与外部隔绝,起到保温作用。实验结果表明:配碳量为26%及以上时,还原后有剩余的含碳物质存在,钒钛磁铁矿的还原效果好。当微波功率基本保持不变时,钒钛磁铁矿的温度与时间成2次函数关系上升,升温速率则随时间延长而下降。在钒钛磁铁矿微波碳还原过程中,随着还原反应的进行产生的气体不断增多以及气体在温度的作用下发生膨胀,导致微波炉炉膛压力随时间成上升关系。本实验条件下,钒钛磁铁矿微波碳还原的最优条件是:1500℃,配碳量29.9%,自然碱度,0.6atm。更多还原

【Abstract】 The resource of vanadium titano-magnetite is abundant in China. The present process of vanadium titano-magnetite can not make full use of it and lead to waste of titanium resource. In order to obtain a new way to make full use of vanadium titano-magnetite, the mixture of vanadium titano-magnetite and coal powder was heated by microwave to acquire the reduction characteristic. The conclusions of this work are as fellows:Temperature has important influence on the reduction degree of vanadium titano-magnetite and the composition of the reduction product. When the reduction temperature is 1300℃, the reduction product contains Fe, Fe3O4, FeTiO₃ and Fe₂TiO₅。When the reduction temperature is 1400℃, the reduction product contains Fe, Fe3O4, FeTiO₃, MgTiO₃, Fe₂TiO₅, TiO₂, MgAl₂O₄. When the reduction temperature is 1500℃, the slag and the metal separate. The metal is Fe—V alloy. The slag contains FeTiO₃, MgTiO₃, Fe₂TiO₅, Ti₃O₅, MgAl₂O₄, FeO.The addition of CaO to the vanadium titano-magnetite can make the reduction of FeTiO₃ and 2FeO.TiO₂ easily and the separation of slag and iron. The separation of the slag and metal becomes weaken because the microwave absorbancy of the mixture drops off if the addition of CaO is excessive. The results indicate that the reduction is better when the basicity is 1.2, 1.4, 1.6.When the addition of carbon to vanadium itano-magnetite is excessive, the excessive carbon will effect the reduction atmosphere and there is surplus of carbon after the completion of reduction, the surplus carbon covering the reduction production can insulates the production and keep the temperature. The experimental results indicate that there is surplus of carbon and the reduction is better when the addition of carbon is above 26%.When the microwave power is unchanged, the temperature and time is a function of 2. The heating rate decreases with time. The microwave oven pressure increases with time becase the gas production increases and the volume inflates.Under the experimental condition, when the reduction temperature is 1500℃, the carbon content is 29.9%, the basicity is natural, the initial pressure is 0.6atm, the reduction is the best.更多还原