【摘要】 我国每年排放的含钛高炉渣超过300万t，该渣TiO₂含量为10%～25%，目前对此渣的综合利用主要是制备建筑材料，攀西地区建设了含钛高炉渣制备富钛料、碳化钛或碳氮化钛的工业示范生产线，但均存在一定的局限性，现阶段多数含钛高炉渣的处置方式为堆存。有学者提出选择性析出技术，即通过添加剂改性含钛高炉渣，使钛以钙钛矿形式存在，然后通过重选分离钙钛矿并作为提钛原料，此方法的钛回收率低于48%。针对此问题，本研究在此基础上提出了钙钛矿晶形转变技术，即通过添加CaO、高钛渣、CaTiO₃转变钙钛矿晶形来提升重选回收率，采用试验考察了各添加剂对钛回收率的影响，并根据表征结果进行了晶形转变机理分析，得到以下主要结论。当CaO、高钛渣、CaTiO₃添加量分别为20%、25%、17%时，钙钛矿以等轴晶析出，钛的重选回收率为68.41%；后续循环生产时，采用重选精矿代替钙钛矿添加，最佳精矿添加量为50%，此时钛的重选回收率为68.42%；钙钛矿晶形转换技术与选择性析出技术的主要区别在于钙钛矿的晶形，晶形转换技术的产物是等轴晶，选择性析出技术的产物是树枝晶，等轴晶钙钛矿单体解离度更高，从而增大钛回收率。本研究结果可以为含钛高炉渣的资源回收利用提供参考。更多还原

【Abstract】 More than 3 million tons of titanium-bearing blast furnace slag are discharged every year in China, and the TiO₂ content of the slag is 10%-25%. At present, the comprehensive utilization of the slag is mainly to prepare building materials. An industrial demonstration production line for the preparation of titanium-rich materials, titanium carbide or titanium carbonitride from titanium-containing blast furnace slag has been built in Panxi area, but there are some limitations. At present, most of the titanium-containing blast furnace slag is disposed by stacking. Some scholars have proposed selective precipitation technology, that is, titanium-containing blast furnace slag is modified by additives to make titanium exist in the form of perovskite, and then perovskite is separated by gravity separation and used as raw material for titanium extraction. The titanium recovery rate of this method is less than 48%. In view of this problem, this study proposes a perovskite crystal transformation technology on this basis, that is, by adding CaO, high titanium slag, and CaTiO₃ to transform the perovskite crystal to improve the recovery rate of gravity separation. The effects of various additives on the recovery rate of titanium were investigated by experiments, and the mechanism of crystal transformation was analyzed according to the characterization results. The following main conclusions were obtained. When the addition amount of CaO, high titanium slag and CaTiO₃ is 20%, 25% and 17% respectively, the perovskite is precipitated as equiaxed crystal, and the recovery rate of titanium is 68. 41%. In the subsequent cycle production, the gravity concentrate is used instead of perovskite. The optimum concentrate addition is 50%, and the gravity recovery of titanium is 68. 42%. The main difference between perovskite crystal transformation technology and selective precipitation technology is the crystal form of perovskite. The product of crystal transformation technology is equiaxed crystal, and the product of selective precipitation technology is dendrite. The degree of dissociation of equiaxed perovskite monomer is higher, thus increasing the recovery rate of titanium. The results of this study can provide a reference for the resource recovery and utilization of titanium-containing blast furnace slag.更多还原