CaO和Na2CO3用量对高磷鲕状赤铁矿石深度还原分选的影响

CaO 和Na 2CO 3用量对高磷鲕状赤铁矿石深度还原

分选的影响

栗艳锋1，

2

韩跃新1，

2

孙永升1，

2

张

琦1，

2（1.东北大学资源与土木工程学院，辽宁沈阳110819；

2.难采选铁矿资源高效开发利用技术国家地方联合工程研究中心，辽宁沈阳110819）

摘要

采用深度还原技术处理高磷鲕状赤铁矿可以取得良好的技术经济指标，但添加剂（如CaO 和Na 2CO 3）

在深度还原过程中的作用仍需深入研究。以鄂西某宁乡式高磷鲕状赤铁矿石为原料，考察还原温度、还原时间、碳氧摩尔比对还原指标的影响。结果表明，适宜的深度还原条件为还原温度1523K、还原时间30min、碳氧摩尔比2.0，获得的还原物料铁金属化率为86.21%，还原物料经磁选获得的磁选精矿铁品位为91.69%、回收率为92.23%。在最佳还原条件下分别以CaO 和Na 2CO 3为添加剂进行深度还原试验，采用化学成分分析和X 射线衍射（XRD ）探究了CaO 和Na 2CO 3用量对高磷鲕状赤铁矿石深度还原分选指标、脱磷效果和物相转变的影响。结果表明，添加CaO 和Na 2CO 3均可抑制深度还原过程中铁橄榄石的生成，有效降低精矿中磷含量，提高铁回收率；CaO 可与物料中的SiO 2和Al 2O 3反应生成硅灰石和钙铝黄长石等高熔点硅酸盐，不利于铁品位的提高；Na 2CO 3可与物料中的SiO 2和Al 2O 3反应生成钠长石等低熔点硅酸盐，有利于铁品位的提高。

关键词高磷鲕状赤铁矿深度还原

添加剂

CaO

Na 2CO 3

物相变化

脱磷

中图分类号TD925.7

文献标志码A

文章编号1001-1250（2019）-02-054-06

DOI 10.19614/ki.jsks.201902010

Effects of CaO and Na 2CO 3Dosage on Beneficiation during Coal -based Reduction of High -phosphorus Oolitic Hematite Ore

Li Yanfeng 1，2Han Yuexin 1，2Sun Yongsheng 1，2Zhang Qi 1，

2（1.School of Resources and Civil Engineering,Northeastern University,Shenyang 110819，China ；2.National -Local Joint Engineering Research Center of Refractory Iron Ore Resources Efficient Utilization Technology ，Shenyang 110819，China ）Abstract

High -phosphorus oolitic hematite treated with coal -based reduction technology can have good technical -eco⁃

nomic indicators ，but the role of additives such as CaO and Na 2CO 3in the reduction process still needs to be further studied.

The influence of reduction temperature ，reduction time ，mole ratio of C to O on reduction index was investigated ，taking high -

phosphorus oolitic hematite from Western Hubei as research object.The results showed that the appropriate reduction condi⁃tions were the reduction temperature of 1523K ，the reduction time of 30min and mole ratio of C to O is 2.0，the metallization

degree of the reduced products was 86.21%，the iron grade of magnetic separation was 91.69%，and the recovery was 92.23%.The effects of CaO and Na 2CO 3dosage on separation indexes was investigated on the optimum coal -based reduction

conditions ，the chemical composition analysis and X -ray diffraction （XRD ）were used to investigate dosage of CaO and Na 2CO 3on separation index of high -phosphate oolitic hematite ，dephosphorization and phase transition.The addition of CaO and Na 2CO 3can inhibit the formation of fayalite in reduction process ，effectively reduce the phosphorus content in concentrate and improve the iron recovery.CaO can react with SiO 2and Al 2O 3in the samples to form high -melting -point silicates such as

wollastonite and gehlenite ，which is not conducive to the improvement of iron grade.Na 2CO 3can react with SiO 2and Al 2O 3in

the samples to form low -melting -point silicate such as albite ，which is conducive to the improvement of iron grade.Keywords

High -phosphorus oolitic hematite ，Coal -based reduction ，Additive ，CaO ，Na 2CO 3，Phrase changes ，De⁃

phosphorization

收稿日期2018-12-11

基金项目国家自然科学基金项目（编号：51604063）。作者简介

栗艳锋（1989—），男，博士研究生。

总第512期2019年第2期

金

属矿山

METAL MINE

Series No.512February 2019

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