DOC《直接还原处理低品位钒钛磁铁精矿》

直接还原处理低品位钒钛磁铁精矿 白云1,2,3,陈德胜2,3,马文会1,王丽娜2,3,赵宏欣2,3,甄玉兰2,3,于宏东2,3,齐涛1,2,3 (1.

昆明理工大学 冶金与能源工程学院,昆明 650000;

2.中国科学院 过程工程研究所绿色过程与工程重点实验室,北京 100190;

3.中国科学院 过程工程研究所湿法冶金与清洁生产国家工程实验室,北京 100190) 摘要:在1 000~1

300 ℃添加少量Na2CO3+NaCl复配添加剂,以无烟煤做还原剂等温还原低品位钒钛磁铁精矿,再通过磁选分离获得铁精粉和钒钛渣.考察了C/Fe摩尔比、还原温度和还原时间对铁的还原、钒钛迁移富集行为以及物相转化规律的影响.结果表明,C/Fe摩尔比和反应温度对直接还原过程中有价组分迁移富集的影响很大,当C/Fe摩尔比为1.2时,在1

200 ℃还原2 h,钒钛磁铁矿精矿的金属化率可达到92.8%,还原后钒主要富集在钛渣相中,有效实现了铁与钒/钛的分离. 关键词:低品位钒钛磁铁精矿;

直接还原;

金属化率;

分离 中图分类号:TL212.1+2 文献标志码:A 文章编号:1007-7545(2017)09-0000-00 Treatment of Low Grade Vanadium-Bearing Titanomagnetite Concentrates by Direct Reduction BAI Yun1,2,3, CHEN De-sheng2,3, MA Wen-hui1, WANG Li-na2,3, ZHAO Hong-xin2,3, ZHEN Yu-lan2,3, YU Hong-dong2,3, QI Tao1,2,3 (1. Kunming University of Science and Technology, Kunming 650000, China;

2. Key Laboratory of Green Process and Engineering, Institute of Process Engineering, CAS, Beijing 100190, China;

3. National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, CAS, Beijing 100190, China) Abstract:Low grade vanadium-bearing titanomagnetite concentrates were reduced isothermally with addition of a small amount of Na2CO3+NaCl at

1 000~1

300 ℃ and anthracite as reductant. Iron concentrates and vanadium-bearing titanium slag were obtained by magnetic separation. The effects of C/Fe molar ratio, reduction temperature, and reduction time on metallization degree of iron, content of V/Ti in samples, and phase transformation were investigated. The results show that C/Fe molar ratio and reduction temperature have great impacts on direct reduction process. Metallization degree is 92.8% under the conditions including C/Fe molar ratio of 1.2, reduction temperature of

1 200 ℃, and reduction time of

2 h. Vanadium is enriched in titanium slag after reduction. Efficient separation between Fe and V/Ti is achieved. Key words:low grade vanadium-bearing titanomagnetite concentrates;

direct reduction;

metallization ratio;

separation 钒钛磁铁矿是钒、钛的重要来源.除攀西以外,在我国河北、辽西、新疆等地还蕴藏有丰富的低品位钒钛磁铁矿[1-2].通常,总铁低于20%的铁矿被归为低品位矿.虽然低品位矿中铁含量较低,但其中伴生的钒、钛资源量并不少.因此,低品位钒钛磁铁矿中钒、钛资源丰富,具有很大的开发应用潜力. 目前针对低品位钒钛磁铁矿的研究基本集中在地质勘探、矿床成矿特征、地质特征、采矿方法、工艺矿物学研究等方面[3-5],选矿方面有少量针对钒钛磁铁精矿的选别[6]、以及个别含磷低品位矿中磷的选别[7],而对如何利用其中的钒和钛资源未见报道.随着我国优质钒钛资源的逐年减少,以低品位钒钛磁铁矿资源为研究对象开展前瞻性基础研究,对提高钒钛资源保障量和今后此类资源的高效综合利用具有重要意义. 钒钛磁铁矿经选矿分离后得到钒钛磁铁精矿和钛精矿.工业上采用高炉―转炉流程处理钒钛磁铁精矿回收铁和钒,仅适用于处理总铁大于55%的钒钛磁铁精矿,高炉冶炼后钛进入高炉渣(TiO2 20%~25%)不能经济利用[8],导致资源浪费和环境污染.近年来,非高炉路线的直接还原技术备受关注,被认为是综合利用铁、钒、钛的很有潜力的方法之一,具有工艺流程短、设备简单、能有效回收钒钛磁铁精矿中的钛资源等优点[9-10].但是这些研究大部分是针对攀西地区的钒钛磁铁精矿,针对低品位钒钛磁铁矿分选出的低品位钒钛磁铁精矿的直接还原工艺报道较少.本文以辽西地区低品位钒钛磁铁矿经分选后得到的低品位钒钛磁铁精矿(TFe