焙烧方式对含砷金精矿中金、银浸出率的影响

某含砷金精矿中金矿物嵌布粒度较细,金主要以硫化物(黄铁矿、毒砂)包裹金形式存在。采用焙烧预处理-氰化浸出工艺,研究了一段焙烧、两段焙烧和添加剂焙烧对氰化浸出的影响。结果表明,采用常规一段、两段焙烧方式,金浸出率均未达到90%,银浸出率低于50%; 添加剂焙烧效果显著,在焙烧温度650 ℃、时间1.0 h、添加剂用量NaXY 100 kg/t+YC-1 20 kg/t的条件下,金浸出率达到93.56%,银浸出率达62.45%。

Effect of Roasting Method on Leaching Rate of Gold and Silver from Arsenic-Containing Gold Concentrates

The arsenic-containing gold concentrates used in the experimental study have a fine dissemination of gold minerals, with gold predominately wrapped in the sulphide minerals, such as pyrite and arsenopyrite. A process consisting of pretreatment with roasting and cyanidation leaching was adopted in the experiment and the effects of one-stage roasting, two-stage roasting and the roasting with additives on the following cyanidation leaching results were investigated in the experiments. It is found that the traditional one-stage roasting and two-stage roasting process just lead to the gold leaching rate less than 90% and silver leaching rate less than 50%. However, the roasting with additives can bring in a remarkable effect, showing that gold leaching rate is up to 93.56% and silver leaching rate reaches 62.45% after an one hour roasting process at 650 ℃ with additives of NaXY 100 kg/t and YC-1 20 kg/t.