第36卷第12期 北京科技大学学报 Vol.36 No.12 2014年12月 Journal of University of Science and Technology Beijing Dec.2014 钒钛磁铁精矿直接还原过程中金属铁颗粒长大特性 赵龙胜2)，陈德胜2》，王丽娜2，齐涛2》，赵宏欣2)，薛天艳23》， 王建冲2,3) 1)中国科学院大学，北京1000492)中国科学院过程工程研究所湿法治金清洁生产技术国家工程实验室，北京100190 3)中国科学院过程工程研究所绿色过程与工程院重点实验室，北京100190 ☒通信作者，E-mail:linawang@pe.ac.cn 摘要通过钒钛磁铁矿精矿直接还原实验，研究了不同还原剂和添加剂对还原过程金属铁颗粒长大的影响.提高还原温度 能促进还原产物中金属铁颗粒的长大，金属铁颗粒中V含量也显著增加.与用无烟煤和褐煤还原产物相比，用烟煤还原产物 中金属铁颗粒明显长大，这是由烟煤中高灰分含量所引起的.金属铁颗粒长大机理的研究表明：Na,C0,和Na,SiO,的熔点较 低，且能破坏铁橄榄石和铁尖晶石的结构，并生成一些低熔点物质，而S02能与铁橄榄石形成低共熔混合物.这些低熔点物 质都有助于改善金属铁相的扩散，从而促进金属铁颗粒长大 关键词钛磁铁矿：精矿：直接还原：铁颗粒：颗粒长大 分类号TF533.1 Grain growth characteristics of metallic iron in the direct reduction of vanadi- um-bearing titanomagnetite concentrates ZHAO Long-sheng,CHEN De-sheng,WANG Li-na,QI Tao,ZHAO Hong-xin,XUE Tian-yan,WANG Jian-chong 1)University of Chinese Academy of Sciences,Beijing 100049,China 2)National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology,Institute of Process Engineering,Chinese Academy of Sci- ences,Beijing 100190,China 3)Key Laboratory of Green Process and Engineering,Institute of Process Engineering.Chinese Academy of Sciences,Beijing 10019,China Corresponding author,E-mail:linawang@ipe.ac.cn ABSTRACT The effects of reductants and additives on the grain growth of metallic iron were investigated during the direct reduction of vanadium-bearing titanomagnetite concentrates.It is found that both the particle size and the vanadium content of metallic iron in re- duced samples considerably increases as the reduction temperature rises.In comparison with a reduced sample using anthracite or lig- nite as a reductant,the particle size of metallic iron in a reduced sample using bitumite as a reductant considerably increases.This may be attributed to the high ash content of bitumite.A further study on the mechanism of the grain growth of metallic iron shows that Na CO,and Na SiO,with low melting points,decompose the structures of fayalite and hercynite and generate some low-melting-point phases,while SiOreact with fayalite and form eutectic mixtures.These substances with low melting points can improve the diffusion of metallic iron in reduced samples and facilitate the grain growth of metallic iron. KEY WORDS titanomagnetite:concentrates;direct reduction:iron particles:grain growth 我国四川攀西地区的钒钛磁铁矿是一种以铁、 种有用元素的矿产资源，具有很高的综合利用价 钒和钛为主，并伴生有少量铬、镍、钴、铂族、钪等多 值-习.目前较成熟的技术是采用高炉一转炉流程 收稿日期：201308-29 基金项目：国家自然科学基金资助项目(51374191,51125018,21006115,51104139)：国家重点基础研究发展计划资助项目(2013CB632601) DOI:10.13374/j.issn1001-053x.2014.12.005:http://journals.ustb.edu.cn第 36 卷 第 12 期 2014 年 12 月 北京科技大学学报 Journal of University of Science and Technology Beijing Vol． 36 No． 12 Dec． 2014 钒钛磁铁精矿直接还原过程中金属铁颗粒长大特性 赵龙胜1，2，3) ，陈德胜2，3) ，王丽娜2，3) ，齐 涛2，3) ，赵宏欣2，3) ，薛天艳2，3) ， 王建冲2，3) 1) 中国科学院大学，北京 100049 2) 中国科学院过程工程研究所湿法冶金清洁生产技术国家工程实验室，北京 100190 3) 中国科学院过程工程研究所绿色过程与工程院重点实验室，北京 100190  通信作者，E-mail: linawang@ ipe． ac． cn 摘 要 通过钒钛磁铁矿精矿直接还原实验，研究了不同还原剂和添加剂对还原过程金属铁颗粒长大的影响． 提高还原温度 能促进还原产物中金属铁颗粒的长大，金属铁颗粒中 V 含量也显著增加． 与用无烟煤和褐煤还原产物相比，用烟煤还原产物 中金属铁颗粒明显长大，这是由烟煤中高灰分含量所引起的． 金属铁颗粒长大机理的研究表明: Na2CO3 和 Na2 SiO3 的熔点较 低，且能破坏铁橄榄石和铁尖晶石的结构，并生成一些低熔点物质，而 SiO2 能与铁橄榄石形成低共熔混合物． 这些低熔点物 质都有助于改善金属铁相的扩散，从而促进金属铁颗粒长大． 关键词 钛磁铁矿; 精矿; 直接还原; 铁颗粒; 颗粒长大 分类号 TF533. 1 Grain growth characteristics of metallic iron in the direct reduction of vanadi￾um-bearing titanomagnetite concentrates ZHAO Long-sheng1，2，3) ，CHEN De-sheng2，3) ，WANG Li-na2，3) ，QI Tao2，3) ，ZHAO Hong-xin2，3) ，XUE Tian-yan2，3) ，WANG Jian-chong2，3) 1) University of Chinese Academy of Sciences，Beijing 100049，China 2) National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology，Institute of Process Engineering，Chinese Academy of Sci￾ences，Beijing 100190，China 3) Key Laboratory of Green Process and Engineering，Institute of Process Engineering，Chinese Academy of Sciences，Beijing 100190，China  Corresponding author，E-mail: linawang@ ipe． ac． cn ABSTＲACT The effects of reductants and additives on the grain growth of metallic iron were investigated during the direct reduction of vanadium-bearing titanomagnetite concentrates． It is found that both the particle size and the vanadium content of metallic iron in re￾duced samples considerably increases as the reduction temperature rises． In comparison with a reduced sample using anthracite or lig￾nite as a reductant，the particle size of metallic iron in a reduced sample using bitumite as a reductant considerably increases． This may be attributed to the high ash content of bitumite． A further study on the mechanism of the grain growth of metallic iron shows that Na2CO3 and Na2 SiO3，with low melting points，decompose the structures of fayalite and hercynite and generate some low-melting-point phases，while SiO2 react with fayalite and form eutectic mixtures． These substances with low melting points can improve the diffusion of metallic iron in reduced samples and facilitate the grain growth of metallic iron． KEY WOＲDS titanomagnetite; concentrates; direct reduction; iron particles; grain growth 收稿日期: 2013--08--29 基金项目: 国家自然科学基金资助项目( 51374191，51125018，21006115，51104139) ; 国家重点基础研究发展计划资助项目( 2013CB632601) DOI: 10． 13374 /j． issn1001--053x． 2014． 12． 005; http: / /journals． ustb． edu． cn 我国四川攀西地区的钒钛磁铁矿是一种以铁、 钒和钛为主，并伴生有少量铬、镍、钴、铂族、钪等多 种有用元素的矿产资源，具有很高的综合利用价 值［1--2］． 目前较成熟的技术是采用高炉--转炉流程