核矿石对低钛型钒钛磁铁精粉烧结制粒的影响

 为了改善低钛型钒钛磁铁精粉的制粒性能，研究了核矿石对低钛型钒钛磁铁精粉烧结制粒行为的影响。研究结果表明，低钛型钒钛磁铁精粉粒度粗，比表面积小，形貌主要为光滑的不规则形状和片状，颗粒间黏附力弱，不利于烧结混合料制粒；低钛型钒钛磁铁精粉的颗粒长大指数和均匀性指数的指标较好，制粒效率和制粒后准颗粒小球的均匀程度不是低钛型钒钛磁铁精粉制粒的限制性环节，核矿石种类对颗粒长大指数和均匀性指数的影响较小。相对普通矿粉而言，低钛型钒钛磁铁精粉制粒后准颗粒小球的抗热粉化指数较低，破损指数较高；不同核矿石条件下，准颗粒小球的抗粉化指数和破损指数差异均较大；褐铁矿作为核矿石时，制粒后准颗粒小球抵抗外力冲击和热气流冲击的能力最强，赤铁矿次之，烧结返矿最差。综合分析核矿石对低钛型钒钛磁铁精粉烧结混合料制粒的影响，核矿石的优选顺序为褐铁矿、赤铁矿和烧结返矿。

Effects of nuclei ores on granulation behavior of low-titanium magnetite concentrate

Effects of the nuclei ores on the granulation behavior of the low-titanium magnetite concentrate(LTC)were investigated using micro-drum granulation equipment in order to improve the granulation properties of the LTC. The re-sults show that the LTC has coarse grain size,small specific surface area,and the granule morphologyof the LTC is mainly smooth irregular shape and the adhesion among granules is relatively week. The granulation index(GI)and uni-formity index(UI)of the LTC are relatively high,the granulating efficiency and the uniformity of quasi-particles are not the restrictive link for the LTC granulation.There is no evident relationship between nuclei ores and the granulation index or uniformity index. Compared with other iron ores,the resistance index of the thermal disintegration(KI)of quasi-par-ticlesis relatively high but the damage index(DI)exhibits the opposite behavior. The KI and DI of the quasi-particles varies greatly for the different nuclei ores. Given that there are three kinds of nuclei ores can be selected in the low-titani-um magnetite concentrate granulation process,when the limonite acts as nuclei ore,the quasi-particles has the strongest capability of impact-resistance and hot pulverization resistance,but for the hematite,the capabilities of impact-resis-tance and hot pulverization resistance are comparatively worse,and the impact-resistance and hot pulverization resis-tance of the sinter return is the worst.