地质冶金学建模在刚果(金)SICOMINES难处理铜钴矿中的应用

Application of geometallurgical modeling in SICOMINES refractory copper-cobalt deposit in Congo(Kinshasa)

SICOMINES铜钴矿位于刚果(金)科卢韦齐南西侧,是中部非洲加丹加铜矿带的典型矿床.由于矿床成因复杂,矿石中形成了十多种铜、钴矿物,尤其各种钴矿物选冶性质差异大,一直存在选冶工艺复杂,生产不稳定,回收率低的问题.为此,本文首次采用Datamine和Leapfrog软件构建了钴的冶金地质学模型,首先,收集历史勘查资料,建立矿区地层和矿化域模型,初步获得钴在空间的品位变化规律;其次,进行采样设计,采集代表钴在地层和矿体中品位分布规律的工艺矿物学样品;再次,采用工艺矿物学综合手段,获得各样品中矿物含量和钴赋存状态的定量数据,并采用单一域赋值法和距离幂次反比法等插值手段写入模型;然后,根据钴矿物选冶类型的空间分布规律划分了5个空间选冶域,分别为适于浮选域(TYPE1)、适于磁选域(TYPE2)、适于浮选-磁选联合分选域(TYPE3)、适于浸出域(TYPE4)和难以分选域(TYPE5),构建初步地质冶金学模型;最后,通过对5个选冶域中综合样分别进行选矿实验来验证模型.实验结果显示,采用矿山现行的浮选–磁选联合工艺流程,5个选冶域中钴的回收率和精矿品位差距明显,现有工艺流程只适用于空间域TYPE1、TYPE2和TYPE3,模型中选冶域的划分合理.根据模型中钴的赋存状态和有效钴品位进行配矿,可以起到稳定现行生产工艺,提高钴回收率的作用,同时,构建的地质冶金学模型为今后实现SICOMINES矿区钴的分采分选提供指导.

The SICOMINES Cu–Co ore deposit is located in southwest Kolwezi,Congo(Kinshasa),and is a typical deposit in the Katanga Copper Belt in central Africa.Dozens of Cu and Co minerals exist in the deposit as a result of the superposition and transformation of three complex ore-forming stages,including the sediment-hosted,hydrothermal,and oxidation periods;some of these minerals include heterogenite,carrollite,chalcocite,malachite,Co-containing malachite,spherocobaltite,Cu/Co-containing psilomelane,and Co-containing limonite.The mineralogy and processability properties among Co minerals differ considerably.The variability in Co minerals poses substantial challenges in establishing a universal beneficiation or extraction process that can accommodate all geometallurgical variations.The current Co-recovery process integrates flotation and magnetic separation techniques.However,the lack of fundamental knowledge about the spatial distribution of Co minerals and the poor adaptability of current Co-recovery processes to adapt to variable ores contribute to considerable Co losses in mine tailings.The recovery efficiency for Co is generally low,and the operational stability of the process is unstable.To address the issues,this study devised a geometallurgical model of Co in an ore body using Datamine and Leapfrog software for the first time.Initially,historical exploration data were collected,strata and mineralized domain models were developed,and the spatial variation in Co grade was preliminarily obtained.Subsequently,a sampling design was implemented to collect samples for process mineralogical research,effectively representing the Co-grade distribution within the strata and ore bodies.Furthermore,quantitative data of the mineral content and Co-occurrence state for each sample were obtained using a process mineralogical method,and these data were incorporated into the model using interpolation methods such as single-domain assignment and the distance inverse power ratio.As a result,five spatial beneficiation zones were obtained based on the spatial distribution of Co minerals with varying processability properties.These zones were classified as suitable for flotation(TYPE1),suitable for magnetic separation(TYPE2),suitable for combined magnetic separation and flotation(TYPE3),suitable for leaching(TYPE4),and difficult to recover(TYPE5);this classification resulted in the formation of a preliminary geometallurgical model.Finally,comprehensive samples were collected from the five beneficiation zones for the beneficiation experiments.The results revealed that the integrated magnetic separation and flotation process employed in the mine achieved varying Co-recovery efficiencies across the five beneficiation zones.This process proves applicable solely to the spatial domains of TYPE1,TYPE2,and TYPE3.The results also indicated that the classification of beneficiation zones in the geometallurgical model was within reason.Reasonable ore blending,based on the occurrence state of Co and the effective Co grade in the model,contributes to stabilizing current production and enhancing Co recovery.The developed geometallurgy model can be continuously optimized by adding sampling points or mineralogy parameters such as Co mineral particle size,mineral liberation degree,and Co-associated relationship with other minerals.The developed geometallurgy model serves as a valuable guide for the realization of classified mining and separation of Co ores in the SICOMINES mining region and for appropriate management.