(1. 北京科技大學 冶金與生態(tài)工程學院，北京 100083；
2. 北京礦冶科技集團有限公司，北京 100160)
摘 要: 針對當前赤泥資源中鈦直接回收工藝存在選擇性差、回收率低、能耗高等缺陷，本文對拜爾-燒結聯(lián)合赤泥中鈦的賦存狀態(tài)及其在鈣化轉型-選擇性堿溶提鋁過程的物相轉化進行系統(tǒng)研究。結果表明：赤泥中含TiO2 5.40%(質量分數(shù))，其中80.65% TiO2以類質同象形式分散于水鈣鋁榴石中，15.25% TiO2分散于以鈣霞石為主的沸石中。赤泥中鈦經(jīng)鈣化燒結轉型后由分散態(tài)轉型為獨立礦相鈣鈦礦，堿溶過程鋁的溶出率大于90%，鈦則富集于提鋁渣中。轉型過程鈣鈦礦的結晶速度緩慢，在燒結時間為60 min、以2 ℃/min緩冷的條件下，僅52.63%鈣鈦礦結晶粒度大于0.02 mm。當提鋁渣粒度磨細至90%小于0.038 mm時，鈣鈦礦的單體解離度也僅為38.30%。這極大地制約了提鋁渣中鈦的浮選分離與富集，濕法酸浸工藝更適合提鋁渣中鈦的進一步提取。
關鍵字: 赤泥；提鋁渣；鈦；賦存狀態(tài)；水鈣鋁榴石；類質同象；鈣鈦礦
（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
