MgO对烧结矿CaO-Fe_2O_3系初期液相生成的影响

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英文篇名：Effect of MgO on formation of CaO-Fe_2O_3 based initial liquid phase in iron ore sinter 作者：杨楠 ; 郭兴敏 英文作者：YANG Nan;GUO Xing-min;School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing; 关键词：MgO ; 烧结矿 ; 铁酸钙 ; 黏结相 ; 初期液相 英文关键词：MgO;;iron ore sinter;;calcium ferrite;;bonding phase;;initial liquid phase 中文刊名：ZGYE 英文刊名：China Metallurgy 机构：北京科技大学冶金与生态工程学院; 出版日期：2019-05-15 出版单位：中国冶金 年：2019 期：v.29 基金：国家自然科学基金资助项目(U1460201,51374017,51774029) 语种：中文; 页：ZGYE201905005 页数：6 CN：05 ISSN：11-3729/TF 分类号：25-30

摘要

为了研究MgO对烧结过程中CaO-Fe_2O_3系初期液相生成的影响及作用机理,通过DSC研究了不同MgO含量试样在升温过程中液相生成的变化,并通过XRD确定液相生成前MgO对矿物组成的影响。结果表明,试样中MgO含量的增加使得升温过程中初期液相生成量减少,但是初期液相的生成温度没有明显变化。MgO对初期液相的抑制分为两种方式,一种为MgO与Fe_2O_3反应生成含镁磁铁矿,另一种为MgO添加导致CaFe_2O_4分解。这两种方式都使CaO含量升高,促进了高熔点矿物Ca_2Fe_2O_5和含镁磁铁矿的生成,导致液相量降低。通过研究MgO对初期液相生成的影响,为烧结矿中合理添加含镁熔剂提供理论基础。
        In order to study the effect of MgO on the formation of CaO-Fe_2O_3 based initial melt and the reaction mechanism during the sintering process,the variations of liquid phase formation in samples with different MgO content were investigated by DSC during the heating process.In addition,the effect of MgO on the mineral composition before forming the liquid phase was studied by XRD.The results showed that the increase of MgO content decreased the formation of the initial liquid phase.However,the formation temperature of the liquid phase did not change significantly.There were two mechanisms for MgO addition to inhibiting the formation of the initial liquid phase.One was the reaction of MgO with Fe_2O_3 to produce magnetite solid solution.The other one was decomposition of CaFe_2 O_4 caused by the addition of MgO.These two mechanisms relatively increased the CaO content and promoted the formation of Ca_2 Fe_2 O_5 and magnetite solid solution,which were both high-melting temperature minerals,and led to the decrease of the liquid phase.The study of the effect of MgO on the formation of the initial liquid phase was expected to provide a theoretical basis for appropriately adding Mg-bearing flux during iron ore sintering process.

引文

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