微细浸染型金矿碱预处理—非氰化浸出研究

Experimental Research on Micro-disseminated Gold Ore Pretreated by Alkaline and Non-cyanide Leaching

以微细浸染型金矿为研究对象,比较研究了Ca O、Na2CO3及Ca O-Na2CO3混合碱预处理体系的处理效果。结果表明,采用Ca O-Na2CO3混合碱预处理,金浸出效果要优于单一预处理,这与混合体系生成Na OH有关,Na OH与石英及黄铁矿作用,使包裹的金暴露出来,有利于金的浸出。在预处理和浸出过程充气时,浸出效果要优于不充气,这是因为空气中氧气参与了反应,充气降低了扩散层的厚度或使固膜减薄,大幅提高了金的浸出率。试验结果表明,在Ca O用量为50 kg/t、Na2CO3用量为2 kg/t、预处理时间为4 h、浸出剂用量为10 kg/t、液固比为3∶1、浸出时间为14 h、充气量为0.5 m3/h的条件下,金浸出率可达86.09%。

The thesis focuses on research of the micro-disseminated gold ore.Explored the extraction effects,under the condition of wet milling,with non-cyanide leaching agent,pre-treating with lime and sodium carbonate,mixed system is more efficiency than single pretreatment system,which may influenced by the generation of sodium hydroxide.The reaction of sodium hydroxide with quartz and pyrite make the package gold exposed,which is beneficial to the leaching of gold.When inflating in the pretreatment and leaching process,leaching effect is better.This may be oxygen participate in the reaction or reduce the thickness of the diffusion layer and solid film thickness.The results showed that under the conditions of lime dosage was 50 kg/t,sodium carbonate dosage was2 kg/t,pretreatment time was 4 h,a non-cyanide leaching agent was 10 kg/t,leaching time was 14 h,liquid-to-solid ratio was 3∶1,inflatable amounts was about 0.5 m3/h,the gold leaching rate of 86.09% was achieved.