(1. 北京科技大学 冶金与生态工程学院，北京 100083；
2. 北京矿冶科技集团有限公司，北京 100160)
摘 要: 针对当前赤泥资源中钛直接回收工艺存在选择性差、回收率低、能耗高等缺陷，本文对拜尔-烧结联合赤泥中钛的赋存状态及其在钙化转型-选择性碱溶提铝过程的物相转化进行系统研究。结果表明：赤泥中含TiO2 5.40%(质量分数)，其中80.65% TiO2以类质同象形式分散于水钙铝榴石中，15.25% TiO2分散于以钙霞石为主的沸石中。赤泥中钛经钙化烧结转型后由分散态转型为独立矿相钙钛矿，碱溶过程铝的溶出率大于90%，钛则富集于提铝渣中。转型过程钙钛矿的结晶速度缓慢，在烧结时间为60 min、以2 ℃/min缓冷的条件下，仅52.63%钙钛矿结晶粒度大于0.02 mm。当提铝渣粒度磨细至90%小于0.038 mm时，钙钛矿的单体解离度也仅为38.30%。这极大地制约了提铝渣中钛的浮选分离与富集，湿法酸浸工艺更适合提铝渣中钛的进一步提取。
关键字: 赤泥；提铝渣；钛；赋存状态；水钙铝榴石；类质同象；钙钛矿
（1. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China;
2. Beijing General Research Institute of Mining & Metallurgy, Beijing 100160, China）
Abstract:In view of the poor leaching selectivity, low leaching efficiency and high energy consumption of the current titanium recovery progress from red mud resources, this paper conducted an in-depth investigation on the occurrence of titanium in Bayer-sintered red mud and its phase transformation during calcified modifying and selective alkaline leaching process. The results show that the red mud contains 5.40% TiO2, of which 80.65% disperses in hydrogrossular as the form of isomorphism, and 15.25% disperses in zeolites dominated by calcarenite. The titanium in the red mud transforms from the dispersed state to perovskite, an independent mineral phase, after calcification modifying. Then, the leaching efficiency of aluminum above 90% is achieved during alkali leaching, whereas the titanium is enriched in the leaching residue. The crystallization rate of perovskite is slow during the modifying process. The distribution of the perovskite with size ＞0.02 mm is only 52.63% with the holding time of 60 min and slowly cooled rate of 2 ℃/min. Correspondingly, the liberated degree of perovskite is only 38.30% when the leaching residue is ground with fineness of 90% less than 0.038 mm. That limited the application of flotation separation progress. Based on the results, acid leaching is a more potential method for titanium effective recovery in the leaching residue.
Key words: red mud; aluminum leaching residue; titanium; occurrence state; hydrogrossular; isomorphism; perovskite
