含金黄铁矿和白云石浮选分离研究进展

Research Progress in Flotation Separation of Gold-bearing Pyrite and Dolomite

黄铁矿是卡林型金矿中微细颗粒金的主要载体,金的回收率取决于黄铁矿的浮选表现。同时,在卡林型金矿成矿过程中,成矿热液在粉砂质碳酸盐(主要是白云岩)岩层中扩散,增加了白云石等碳酸盐矿物的含量。因此,含金黄铁矿和白云石等碳酸盐矿物伴生是卡林型金矿的主要特点。浮选结果显示,随着卡林型金矿中白云石含量的增加(低、中、高比例),含金黄铁矿的回收率分别为51.3%、38.6%和36.7%。同时,随着给矿中黄铁矿的含量从1.2%上升至3.0%,精矿中白云石的上浮比例可从8.6%提高至18.7%。可见,黄铁矿与白云石之间的相互作用破坏了两者的分选,从而恶化了卡林型金矿的浮选表现。然而,由于缺少该相互作用的研究,其对卡林型金矿浮选的影响机理不明,无法指导工业实践,导致卡林型金矿实际浮选时存在药剂用量大、分选效果差等严重问题。因此,本文收集总结了国内外关于卡林型金矿浮选研究的信息,从黄铁矿的氧化动力学、黄铁矿氧化对黄原酸盐吸附的影响、白云石对黄铁矿浮选的影响、黄铁矿与白云石的分选手段以及现有研究存在的问题和未来的研究方向等六个方面进行介绍并加以评论,以期对将来的研究起到参考作用。

The majority of invisible gold in carlin-type gold is locked up within pyrite.In this case,the successful recovery of invisible gold follows pyrite in flotation.Meanwhile,during the formation of carlin-type gold ores,the hydrothermal fluids disperse in the dolomitic beds,which increased the dolomite proportion in the carlin-type gold ores.Therefore,the coexistence of pyrite and dolomite is the main character in carlin-type gold ores.Flotation recovery of auriferous pyrite with low,medium and high dolomite content is 51.3%,38.6%and 36.7%,and,with the increase in pyrite content from 1.2%to 3.0%,the floating rate of dolomite increases from 8.6%to 18.7%.What might appear to be a logical explanation is that the interactions between pyrite and dolomite deteriorate the flotation performance of carlin-type gold ores.However,due to the lack of researches in the interactions,the correlation between the interactions and flotation performance of carlin-type gold ores is ambiguous,which is difficult to regulate the flotation practice.The flotation of carlin-type gold deposits still faces the challenges of large dosages of reagents,and the unsatisfied separation efficiency.Thus,the information on the flotation separation of carlin-type gold ores published at domestic and abroad has been summarized in this paper,which was divided into six aspects to introduce and comment,including the oxidation kinetics of pyrite,the effects of pyrite oxidation on xanthate adsorption,the effects of dolomite on the flotation performance of pyrite,the separation methods of pyrite and dolomite,the existing problems in the research,and the directions for future research.It is expected to play a reference role in future research.