响应曲面法优化承钢含钒钢渣浸出负组元钙的试验研究

Study on Optimization of Leaching of Negative Component Calcium from Vanadium-bearing Slag of Chenggang by Response Surface Methodology

针对承德某含钒钢渣中钙组元含量高,钒难以浸出的问题,采用氯化铵浸出方式对其进行了提钒预处理研究。通过XRD分析和热力学研究发现,在氯化铵浸出过程中铁酸二钙、硅酸二钙、硅酸三钙为浸出过程的主要反应对象。单因素试验的最佳条件下,钙组元的浸出率可达50.03%。在单因素试验的基础上,通过Design-expert软件设计正交试验,结合响应曲面法考察了因素之间的交互作用及不同因素对试验影响的显著程度,并优化试验指标。结果表明,磨矿细度、浸出温度、浸出时间之间存在显著交互作用;因素的显著程度方面,浸出温度>磨矿细度>浸出时间>浸出液固比;重新优化试验后,在细度-74μm占80%、温度100℃、时间4 h、液固比4的条件下,钙组元的浸出率可达到60.12%,可有效提高氯铵浸钙的试验指标。

In order to solve the problem that vanadium is difficult to leach due to the high content of calcium components in a steel slag containing vanadium in Chengde,the pretreatment of vanadium extraction was studied by means of ammonium chloride leaching.The XRD patterns and thermodynamic study of minerals showed that in the ammonium chloride leaching process,dicalcium ferrite,dicalcium silicate,and tricalcium silicate were the main reaction objects.Under the optimum conditions of single factor test,the leaching rate of calcium components could reach 50.03%.Based on the single factor test,orthogonal experiment was designed via Design-expert software.In the experiment design,response surface method was used to investigate the interaction among four factors,the significance of different factors on the experiment and optimize the experiment index.The results showed that:there were significant interactions among grinding fineness,leaching temperature and leaching time;in terms of the significance of factors,leaching temperature>grinding fineness>leaching time>liquid-solid ratio.After the test was reoptimized,when the grinding fineness of-74μm particle accounted for 80%,the leaching temperature was 100℃,the leaching time was 4 h,and the liquid-solid ratio was 4,the leaching rate of calcium content could reach 60.12%.The test index of calcium leaching with ammonium chloride was effectively improved.