云铜铜渣还原熔分试验分析

Experimental analysis of reduction and melting-separation for copper slag from Yunnan province

为了合理利用云铜渣,采用ITmk3工艺获得高质量粒铁,在实验室条件下进行了一系列的基础研究。通过比较试样全铁质量和熔分得到的粒铁质量,得到了金属铁的收得率,结合化学分析方法,分别得到了试样还原后的金属化率以及熔分后金属铁中的碳质量分数,研究了各个因素对以上指标的影响规律,形成了对云铜渣合理还原熔分的工艺路线,得到如下结论:渣熔化是形成粒铁的必要条件,铁的聚合程度取决于渣铁分离熔化之前铁的渗碳质量分数。渣中SiO_2的存在是渣相低熔点的根本原因,碱度改变时云铜渣的熔化区间会发生变化,但对熔化开始温度的影响不显著。当碱度大于0.4后,添加CaO能显著地提高云铜渣的还原性能。

A series of fundamental studies were conducted under laboratory condition to utilize copper slag from Yunnan province（called CSY hereinafter）reasonably,and in order to produce iron nuggets,the ITmk3 process was applied.The mass ratio of iron nuggets to total iron in ore-coal composite pellet（simplified as OCCP hereinafter）was recorded as iron yield,and the metallization ratio of OCCP after reduction and the carbon content in iron nuggets after melting-separation were gained via the chemical analysis.Finally,reasonable technology route of reduction and melting-separation for CSY was drawn up on the basis of the study on the effect of the each factor on the indexes above.It can be concluded that the slag melting was necessary for iron nuggets formation,and the coalescence extent of iron depended on its carburization content.The existence of constituent SiO2 was a critical cause for low melting point of CSY,and the melting interval of OCCP was affected by the change of basicity,which had little effect on its melting start temperature.When the alkalinity was over 0.4,adding CaO can significantly improve the performance of Yunnan copper slag reduction.