某含金原生矿石的工艺矿物学研究

某含金原生矿石的金品位为5.36×10^-6，金是主要的目标回收矿物。为了查明影响选冶工艺指标的主要因素，对该矿石开展了工艺矿物学研究。通过矿物自动分析仪，对矿石的矿物组成、矿物嵌布特征、金的赋存状态、含金矿物的粒度和含金矿物解离度进行了系统研究，获得了目标矿物的工艺矿物学相关参数。研究结果表明:该矿石中主要金矿物是自然金和银金矿；矿石中金的粒度以细粒和微细粒为主，分别占49.43%和50.57%；金矿物的赋存状态以裸露金为主，占72.71%，包裹金占27.29%。通过分析研究结果得出：提高磨矿细度，使包裹金裸露出来，同时，在浸出之前，采取相应措施对毒砂进行氧化预处理，去除毒砂在浸金过程中的不利影响，有助于提高金的回收率。

Process Mineralogy of a Gold-bearing Primary Ore

The gold grade of a gold-bearing primary ore is 5.36×10^-6.Through analysis,it is known that gold is the main recovery target.Because the process mineralogy information such as the type and content of gold-bearing minerals in the primary ore and the embedded state of target elements are not fully grasped, it is impossible to optimize and adjust the production process accurately and effectively.In order to deeply explore the distribution characteristics of target minerals in the primary ore and further find out the process mineralogical factors affecting the processing and metallurgical indexes,the process mineralogical characteristics of the ore was fully studied, such as the types and contents of gold-bearing minerals, the occurrence state and distribution characteristics of target minerals and elements.Based on the scanning electron microscopy (obtaining the backscatter electron image of minerals),an automatic mineral analyzer consisting of X-ray energy spectrometer (acquiring chemical composition information of minerals) and BPMA analysis software (combining image and composition information of minerals with data in mineral database,and statistic process mineralogical parameters of minerals in samples) was developed by Beijing Institute of Mining and Metallurgical Research.The system consists of eight modules as followed:measurement module,building small reservoir module,mineral matching module，mineral processing module，Block template supplement module,process mineralogy parameter calculation module,database editing module and auxiliary function module.The mineral composition,mineral distribution characteristics,occurrence state of gold,particle size of gold-bearing minerals and dissociation degree of gold-bearing minerals were systematically studied,and the relevant process mineralogy parameters of target minerals were obtained.The results show that the main gold minerals in the primary ore are natural gold and silver goldmine,as well as pyrite,magnetite,arsenopyrite,pyrrhotite and other metal minerals.The gangue minerals are mainly calcite,quartz,mica,dolomite and a small or trace amount of apatite, kaolinite and talc.The particle size of gold in the ore is mainly fine gold and fine gold,accounting for 49.43% and 50.57% respectively.The main embedding state of gold minerals is bare gold, accounting for 72.71% and encapsulated gold for 27.29%.The results show that increasing grinding fineness and exposing wrapped gold are helpful to improve gold recovery.At the same time, before leaching, some measures are adopted to oxidize arsenopyrite to remove its adverse effects in gold leaching process.