04.钾钠氟对赤铁矿球团还原膨胀性能的影响

刘安康，罗果萍，王永斌，朱建国

（内蒙古科技大学材料与冶金学院，内蒙古包头市014010）

关键词：K；Na；F；还原膨胀率

中图分类号：TF046.6 文献标识码：A

摘要：包头铁精矿球团中含有K、Na、F等有害元素，K、Na会造成球团的异常膨胀，而F的存在会使膨胀现象加剧，探究原因，采用分段还原法Fe₂O₃→Fe₃O₄,Fe₃O₄→Fe_xO,Fe_xO→Fe，测量各还原阶段的还原膨胀率，采用光学显微镜及SEM观察焙烧试样和还原产物的形貌。由结果可知，CaF₂抑制了Fe₂O₃→Fe₃O₄阶段的还原膨胀，但K、Na及CaF₂含量较高时，CaF₂反而促进了此阶段的还原膨胀；CaF₂促进了Fe₃O₄→Fe_xO；同时CaF₂促进了铁晶须的生长，加剧了Fe_xO→Fe阶段还原膨胀。

The Influence of K、Na and F in Hematite Pellets on Reduction Swelling

Luo Guoping,Liu Ankang

（School of Material and Metallurgy, Inner Mongolia University of Science and Technology,Baotou014010, Inner Mongolia Autonomous Region, China）

Key words: K；Na；F；reduction swelling.

Abstract: The harmful elements K, Na in Baotou iron ore pellets result in unusual reduction swelling, which is aggravated by element F. The specimens were reduced in three steps as follows:Fe₂O₃→Fe₃O₄,Fe₃O₄→Fe_xO,Fe_xO→Fe and their reduction swelling in each step was measured, respectively. The optical microscope and SEM were used to test the sintered and reduced tablets. As a result,CaF₂ restrains the reduction swelling of Fe₂O₃→Fe₃O_{4 ,}which was promoted by higher content of K,Na and F. CaF₂ also advanced the reduction swelling of Fe₃O₄→Fe_xO and Fe_xO→Fe by producing low melting point slag and promoting the growth of iron whiskers.