氰化尾渣安全处置与金矿选矿全流程风险管控研究

Research on Safe Disposal of Cyanide Tailings and Full-Process Risk Management in Gold Ore Beneficiation

摘要: 氰化尾渣是氰化法提金过程中产生的危险废物，具有总氰高、重金属富集、粒度细、易扬尘、易渗漏等特点，已成为制约黄金行业绿色发展的关键瓶颈。本文基于典型黄金矿山现场调研、工程案例与实验研究，系统梳理氰化尾渣“产生–无害化–最终处置–长期监控”全过程的安全处置技术体系；同时，从选矿厂“原矿–破碎–磨矿–分级–氰化–洗涤–尾渣脱水–尾矿堆存”全流程出发，构建以HACCP为核心的风险管控框架。通过文献综述、机理分析、案例验证，系统阐明了氰化尾渣的理化特性、无害化关键技术、尾矿库风险评价方法及分级管控要点，并以内蒙古某2000 t/d金矿为实例，验证了“压滤干堆–回转窑脱氰–三维在线监测”组合技术的工程效果。研究表明：① 基于毒性物质含量计算与暴露场景仿真的精准分类方法，可使95%以上金矿石氰化尾渣按一般工业固体废物管理，每年减少危险废物约6000万t；② 550℃、20% O₂条件下焙烧30 min，可将尾渣总氰去除率提高至99.8%，同步降解硫氰酸盐至检出限以下；③ 建立“尾渣压滤干堆–库区截排洪–三维在线监测–数字化应急”组合式风险管控模式，可将尾矿库溃坝及突发污染概率降低2个数量级。本文为氰化尾渣安全处置及黄金行业绿色转型提供了系统路径与技术支撑。

Abstract: Cyanide tailings, a hazardous waste generated during gold extraction via the cyanidation process, are characterized by high total cyanide content, heavy metal enrichment, fine particle size, susceptibility to dust emission, and leakage risks. These attributes have made them a critical bottleneck hindering the green development of the gold industry. This study systematically constructs a comprehensive safety disposal framework for cyanide tailings, covering the entire lifecycle from “generation-detoxification-final disposal-long-term monitoring,” based on field investigations at typical gold mines, engineering case studies, and experimental research. Through literature review, mechanism analysis, and case verification, the physicochemical properties of cyanide tailings, key harmless technologies, risk assessment methods for tailings ponds, and key points for graded management and control have been systematically elucidated. Taking a 2000 t/d gold mine in Inner Mongolia as an example. The engineering effectiveness of the combined technology of “pressure filtration and dry stacking-rotary kiln decyanation-three-dimensional online monitoring” has been verified. Research shows: ①Accurate classification method based on toxic substance content calculation and exposure scenario simulation. It can enable over 95% of cyanide tailings from gold ore to be managed as general industrial solid waste, and reduce hazardous waste by approximately 60 million tons annually. ② Calcination at 550℃ in 20% O₂ for 30 minutes. The total cyanide removal rate of tailings can be increased to 99.8%. Simultaneous degradation of thiocyanate to below the detection limit. ③ Establish a combined risk management and control model of “tailings pressure filtration and dry stacking-flood interception and drainage in the reservoir area-three-dimensional online monitoring-digital emergency response”. The probability of tailings dam breach and sudden pollution can be reduced by two orders of magnitude. This article provides a systematic approach and technical support for the safe disposal of cyanide tailings and the green transformation of the gold industry.