含银难处理金精矿焙烧过程添加剂的研究及应用

Study and Application of Additive in Roasting Process for Silver Bearing Refractory Gold Concentrates

针对含银难处理金精矿,研究焙烧过程添加剂种类及其用量、焙烧工艺主要参数包括温度、时间等对金、银、铜浸出率的影响,并对焙烧反应热力学及银物相进行分析。结果表明,添加2%氢氧化钠作为添加剂,焙烧温度650℃、焙烧时间2h,银浸出率由43.62%显著提高至75.65%,金、铜的浸出率亦有不同程度提高,其浸出率分别为91.73%、92.50%。焙烧反应热力学及银物相分析表明,加入氢氧化钠焙烧可降低硅酸盐对银的包裹。生产实践表明,焙烧过程添加氢氧化钠作为添加剂可取得良好技术经济指标。

The effects of type and dosage of additive,roasting temperature and duration on leaching rates of gold,silver and copper were investigated in treating process of silver-bearing refractory gold concentrates.In addition,the thermodynamics of roasting reaction and silver phase were analyzed.The results show that leaching rate of silver is improved from 43.62% without NaOH addition to 75.65% with NaOH dosage of2% when roasting temperature is 650 ℃ and roasting time is 2h.The leaching rate of gold and copper is also improved in varying degrees, which is 91.73% and 92.50% respectively.The analysis of thermodynamics of roasting reaction and silver phase shows that adding NaOH can reduce the silicate bound for silver.The industrial practice shows that with addition of NaOH as additive in roasting process of silver bearing refractory gold concentrates can achieve good technical-economic indexes.