电炉渣资源利用特性及铬的浸出特性

Beneficial Reuse of EAF Slag and Its Leaching Behavior of Cr

研究了不锈钢冶炼工艺中EAF渣的资源利用特性和渣中铬的浸出特性,结果表明:EAF渣呈碱性,渣中物相主要有Ca2SiO4、Ca3Mg(SiO4)2、MgCr2O4等,值得关注的Cr2O3质量分数为2.92%,具有较高的回收价值,但是渣中的金属元素基本上均匀分布在各粒度段中,因此其回收利用具有一定的困难。钢渣中铬的浸出测试结果表明:EAF渣中的铬在去离子水中浸出量与钢渣粒径成反比,与反应时间、液固比成正比,电磁搅拌改善了浸出的动力学条件,有利于铬的浸出,浸出液中的Cr(Ⅵ)占浸出总铬的50%以上。在酸性情况下,浸出铬的质量增加,但均以毒性较小的形态存在。

The structure and properties of EAF slag and it＇s leaching behavior of Cr were studied. The results indicate that the main minerals in the EAF slag are CazSiO4 , Ca3Mg（SiO4 ）2 and MgCr2O4. The content of Cr203 in EAF slag is 2.92 %. The slag are suitable for beneficial reuse, hut metals in EAF slag are distributed evenly among every particle size. The leaching tests of Cr in slag show that the ratio of Cr leaching rate from slag in deionized water was inversely-proportional to particle size, and directly proportional to leaching time and liquid to solid ratio. Electromagnetic stirring improve the kinetic condition and improve Cr leaching rate. In deionized water, the percentage of Cr（VI） is higher than 50% in all the Cr leached from EAF slag. In acid solution, the volume of Cr leaching from slag increases but all the Cr are in the form of Cr（ Ⅲ ）.