摘要
高砷难处理金矿是目前重要的黄金来源之一,也是传统浮选法和浸出法面临的巨大挑战。印尼某金矿石含金14.6g/t、含砷1.82%,该矿石为典型的高砷微细粒型难处理金矿石,自然金多分布于毒砂和闪锌矿间隙,少量包裹于脉石矿物中。该矿石的分选难点在于原矿中毒砂含量高、自然金裸露程度低、粒级以细粒和微粒为主,分选的重点在于降低砷含量、分离自然金和硫化矿。由于毒砂中存在着高含量的砷,会对选别造成不利影响,采用传统浮选工艺或全泥氰化工艺选别该矿石回收率较低,还会导致大量的砷富集于金精矿中,影响后续的冶炼过程。本试验重点研究了浮选—浮选尾矿氰化浸出工艺和氧化预处理—氰化浸出工艺,在浮选—浮选尾矿氰化浸出工艺中,为了增加细菌氧化的效率,先通过浮选对原矿进行富集得到金精矿,再进行细菌氧化处理,该方法在一定程度上降低了砷含量,使金精矿中的砷由5.98%降低至1.68%;在氧化预处理—氰化浸出工艺中,采用过硫酸钾(K2S2O8)作为氧化剂来处理原矿,结果表明,过硫酸钾对于氧化分解矿石中的黄铁矿和毒砂有较好的效果,砷含量由1.82%降低至1.05%。综合考虑,最终确定过硫酸钾氧化预处理—氰化浸出工艺的效果更好,金的浸出率可达88.49%,金的总回收率为87.97%,尾矿中金含量降至1.01g/t,实现了矿石中金的高效回收。研究结果可为此类难处理金矿的综合利用和回收提供参考和借鉴。
High arsenic refractory gold ore is currently one of the important sources of gold,and it is also a huge challenge faced by traditional flotation and leaching methods.A gold ore in Indonesia contains 14.6 g/t of gold and 1.82%of arsenic.This ore is a typical high arsenic fine-grained refractory gold ore,with natural gold mainly distributed in the gaps between arsenopyrite and sphalerite,and a small amount wrapped in gangue minerals.The difficulty in sorting this ore lies in the high content of arsenic in the raw ore,the low degree of exposure of natural gold,and the main particle size of natural gold being fine and micro-fine particles.The key to the separation of this ore is to reduce arsenic content and separate natural gold and sulfide ore.Due to the high content of arsenic in arsenopyrite,it can have adverse effects on selection,using traditional flotation or full slime cyanidation process to separate the ore has a lower recovery,which can also lead to a large amount of arsenic enrichment in the gold concentrate obtained from the separation,affects the subsequent smelting process.This experiment focuses on comparing the flotation-flotation tailings cyanide process with the oxidation pretreatment-cyanide process.In the flotationflotation tailings cyanide process,in order to increase the efficiency of bacterial oxidation,the original ore is first enriched through flotation sample preparation experiments to obtain gold concentrate,which is then subjected to bacterial oxidation treatment.By using this method,the arsenic content was reduced to a certain extent,and the arsenic content in the gold concentrate was reduced from 5.98%to 1.68%.In the oxidation pretreatment-cyanide process,potassium persulfate(K,S,Os)is used as an oxidant to treat the raw ore.Experimental studies have shown that potassium persulfate has a good effect on the oxidation and decomposition of pyrite and arsenopyrite in the ore,reducing the arsenic content from 1.82%to 1.05%.After comprehensive consideration,it was ultimately determined that the potassium persulfate oxidation pretreatment-cyanide process had a better effect,with a gold leaching rate of 88.49%and a total gold recovery of 87.97%.The gold grade of tailings was reduced to 1.01 g/t,achieving efficient recovery of gold in the ore.The results can provide reference for the comprehensive utilization and recovery of this kind of refractory gold ore.
作者
邓哲元
李恩霖
施旭楷
丁辉
迟晓鹏
衷水平
DENG Zheyuan;LI Enlin;SHI Xukai;DING Hui;CHI Xiaopeng;ZHONG Shuiping(Zijin School of Geology and Mining,Fuzhou University,Fuzhou 350108,China;Shandong Xinhai Mining Technology Equipment Co.,Ltd.,Yantai 265500,Shandong,China;Fujian Key Laboratory of Green Extraction and High-Value Utilization of New Energy Metals,Fuzhou University,Fuzhou 350108,China;Zijin Mining Group Co.,Ltd.,Shanghang 364200,Fujian,China)
出处
《有色金属（选矿部分）》
CAS
2024年第8期77-85,共9页
Nonferrous Metals（Mineral Processing Section）
基金
国家自然科学基金资助项目(2274349)
国家重点研发计划项目(2022YFC3900804)。
关键词
高砷金矿
细菌氧化
氧化预处理
氰化浸出
high arsenic-bearing gold ore
bacterial oxidation
oxidation pretreatment
cyanide leaching
