氰化尾渣中总氰化物及硫氰酸盐同步氧化降解无害化处置  

Harmless Disposal Technology for Simultaneous Oxidative Degradation of Total Cyanide and Thiocyanate in Cyanidation Tailings

作　　者：何朦雨 赵冰[1,2] 袁帅 高鹏[1,2] HE Mengyu;ZHAO Bing;YUAN Shuai;GAO Peng(School of Resources&Civil Engineering,Northeastern University,Shenyang 110819,China;National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources,Northeastern University,Shenyang 110819,China)

机构地区：[1]东北大学资源与土木工程学院,沈阳110819 [2]难采选铁矿资源高效开发利用技术国家地方联合工程研究中心,沈阳110819

出　　处：《有色金属（选矿部分）》2024年第5期99-109,共11页Nonferrous Metals（Mineral Processing Section）

基　　金：青年拔尖人才计划项目(XLYC1907162)。

摘　　要：氰化尾渣是黄金冶炼工业产生的危险废物,全球每年的生产量可达上亿吨。因其含有剧毒氰化物,存在环境及安全隐患,因此亟待无害化处置。采用氧化焙烧技术对内蒙某金矿选矿厂的氰化尾渣中总氰化物及硫氰酸盐进行同步氧化降解无害化处置。在氰化尾渣工艺矿物学研究的基础上,利用飞行时间二次质谱(TOF-SIMS)对氰化物赋存状态进行了高精度的定性分析,并开展了氰化尾渣氧化焙烧条件试验,分析了氰化尾渣中总氰化物及硫氰酸盐的热分解规律,比较了不同焙烧温度和焙烧时间对总氰化物及硫氰酸盐脱除效果的影响。试验结果表明,氰化尾渣中总氰化物含量为778.20mg/kg,硫氰酸盐含量为1229.41mg/kg。当氰化尾渣在焙烧温度500℃、焙烧时间30min、O2浓度20%、总气流量为600mL/min的条件下进行氧化焙烧试验,焙烧后总氰化物含量为1.59mg/kg,去除率达到99.80%;硫氰酸盐含量低于检出限,去除率为99.99%,实现了总氰化物及硫氰酸盐同步氧化降解。对氰化尾渣气相产物进行了分析,描述了氰化尾渣在氧化焙烧过程中黄铁矿氧化反应、碳酸盐矿物分解反应以及总氰化物及硫氰酸盐持续氧化分解反应历程。该工艺填补了当前氰化尾渣中总氰化物及硫氰酸盐同步热处理技术上的空白,在去除稳定性高的络合氰化物的同时,高效氧化分解高含量的硫氰酸盐,为氰化尾渣的深度解毒处置提供理论支撑。Cyanidation tailings were industrial hazardous solid waste generated in the process of gold mining industry that the global annual production could reach hundreds of millions of tons.Due to the cyanide gold extraction process,the cyanide content in the cyanidation tailings was seriously excessive,which was easy to cause serious casualties if not handled properly.Therefore,it is necessary to research the harmless disposal of cyanidation tailings in order to make its subsequent resource utilization.Based on the thermal treatment method,the process mineralogy of cyanidation tailings in Inner Mongolia was investigated,the cyanidation tailings were qualitatively analyzed by time of flight secondary mass spectrometry(TOF-SIMS)with high accuracy.The approach of oxidative degradation of total cyanide and thiocyanate in cyanidation tailings simultaneously by roasting was developed.The results showed that,the total cyanide content was 778.20mg/kg,the thiocyanate content was 1229.41 mg/kg.When the cyanidation tailings were roasted at 550℃for 30minutes,at 20%O2concentration and 600mL/min of total gas,the total cyanide content was 1.59 mg/kg,the thiocyanate content was below the detection limit,which means the removal rate of total cyanide after treatment achieved 99.80%,and the removal rate of thiocyanate achieved 99.99%.The gas product of cyanide tailings was analyzed.The oxidation reaction of pyrite,decomposition reaction of carbonates,and continuous oxidation decomposition reactions of total cyanide and thiocyanate were described.This process filled the gap of current simultaneous treatment technology of cyanide and thiocyanate in cyanidation tailings,and efficiently oxidize and decompose high content thiocyanate while removing complex cyanide with high stability,provided theoretical support for the deep detoxification treatment of cyanidation tailings.

关 键 词：氰化尾渣 氧化分解 硫氰酸盐 无害化处置 

分 类 号：TD925[矿业工程—选矿]