PDF《含碳铬铁矿球团的固态还原特性》

第21 卷第

5 期 中国有色金属学报

2011 年5月Vol.

21 No.5 The Chinese Journal of Nonferrous Metals May

2011 文章编号:1004-0609(2011)05-1159-06 含碳铬铁矿球团的固态还原特性 李建臣 1,

2 , 白国华

1 , 李光辉

1 (1. 中南大学 资源加工与生物工程学院,长沙 410083;

2. 中冶华天工程技术有限公司 烧结部,南京 210019) 摘要:通过含碳铬铁矿粉矿成球及还原实验,研究还原温度、内配碳量、还原时间和添加剂对铬铁矿球团预还 原结果的影响.结果表明:还原温度和内配碳量对预还原球团的金属化指标影响非常明显,温度高于

1 200 ℃时, 铬铁矿预还原球团的金属化指标开始明显增加,内配碳比 IC/O=1.2 为铬铁矿预还原球团的较佳配比;

高温 (≥1

300 ℃)时,可实现含碳铬铁矿球团的快速还原(t ≤1 h);

低温时,铁优先于铬还原,总还原反应完成时间需 3~4 h.添加剂强化含碳铬铁矿球团预还原的实验结果表明,不同添加剂对还原反应的影响具有较大差异;

不同温 度下,相同添加剂的催化能力也有一定的差异;

实验所涉及的添加剂中以 NaCl、Na2B4O7・10H2O 和Na2CO3 的催 化效果较好. 关键词:铬铁矿;

球团;

固态还原;

金属化率 中图分类号:TF046;

TF641 文献标志码:A Solid-state reduction properties of carbon-bearing chromite pellets LI Jian-chen1,

2 , BAI Guo-hua1 , LI Guang-hui1 (1. School of Resources Processing and Bio-engineering, Central South University, Changsha 410083, China;

2. Sintering Department, Huatian Engineering and Technology Corporation, MCC, Nanjing 210019, China) Abstract: The balling and reducing experiments of carbon-bearing chromite fines were carried out in laboratory. The effects of reduction temperature, amount of carbon, reduction time and types of additives on the metallization of carbon-bearing chromite pellets were investigated. The results show that the reductivity of carbon-bearing chromite pellet is greatly influenced by the reduction temperature and C/O mole ratio. At the temperature above

1 200 ℃, the metallization of prereduction pellet begins to increase obviously, and IC/O=1.2 is better for the prereduction of chromite pellet. The fast reduction of carbon-bearing chromite pellet can be achieved at high temperature (≥1

300 ℃);

but it needs 3?4 h to finish the reduction reaction at low temperature, and the reduction reaction of iron is easier than that of chromium. The intensifying reduction of carbon-bearing chromite pellet with the help of additives was studied. The results indicate that different additives have great difference in the influence of reduction reaction, and the catalytic property of the same additive also has some difference at different reduction temperatures. For all involved additives in the experiment, NaCl, Na2B4O7・10H2O and Na2CO3 have excellent catalytic performance. Key words: chromite;

pellet;

solid-state reduction;

metallization 铬铁合金是生产不锈钢和高铁素体合金的最重要 合金材料的一种,它可作为钢的添加料生产多种高强 度、抗腐蚀、耐磨、耐高温、耐氧化的特种钢[1] .目前,工业生产中为降低铬铁生产设备的造价,各厂都 趋向使用大型还原封闭电炉,这些电炉必须使用硬块 铬铁矿[2?3] .目前,世界铬铁矿年开采量中块矿约占 基金项目:国家杰出青年基金资助项目(50725416) 收稿日期:2010-03-08;

修订日期:2010-07-05 通信作者:李建臣,硕士研究生, 助理工程师;