基于RSM-BBD的浮选金精矿碘化浸出工艺优化

Optimization of iodization leaching process for gold concentrate flotation based on RSM-BBD

针对碘化法浸金工艺存在成本高、药剂消耗大等问题,基于单因素实验,采用Box-Behnken Design响应面法设计实验方案,考察碘初始质量浓度A、液固比B、浸出时间C对金浸出率的影响,建立响应面回归模型。结果表明,变量因素及其交互作用与金浸出率的主效应关系:C>B>A,AC>BC>AB;在粒径小于74μm的颗粒占总量的99.3%、pH值6~7、碘初始质量浓度7.2 g/L、碘与碘化钾摩尔比1∶6、液固比3.8∶1、浸出时间3.7 h的最佳工艺条件下,金浸出率为91.02%,与预测值91.25%非常相近。该研究可有效降低浸金工艺成本,进一步推进碘化法浸金实现工业化应用。

This paper discusses the efforts to address the higher cost and greater reagents consumption of iodized gold leaching process using iodized gold leaching to extract flotation gold concentrate.The study based on the single-factor test involves designing the test scheme using Box-Behnken Design response surface method;investigating the influences of initial iodine concentration(A),liquid-solid ratio(B)and leaching time(C)on the gold leaching rate;and thereby developing the response surface regression model.The results show that the main effects of variable factors and their interactions on gold leaching rate are C>B>A,AC>BC>AB;the optimal technological conditions following optimization are:particles with grinding fineness smaller than 74μm accounte(fineness ratio)for 99.3%,pH is 6-7;the initial iodine concentration is 7.2 g/L;molar ratio of iodine to iodide is 1∶6;liquid-solid ratio is 3.8∶1;leaching time is 3.7 h,at this time,the gold leaching rate is 91.02%,close to the predicted value of 91.25%.This study promises an effective reduction in the cost of gold leaching process and a wider industrial application of iodization gold leaching.