Research And Application Of Gold Recovery Process From Refractory Ore In Guangnan Laozhaiwan Gold Mine

With the widespread use of gold,the consumption is ever-increasing.In recent years,gold mining resources in large numbers,workable gold ore less and less,unworkable gold ore has become an important resource for gold production.This type of gold ore is difficult to recover using conventional beneficiation methodswhich has extremely complex compositionbecause it exists in the form of symbiosis,companion,parce and so on.Guangnan Laozhaiwan Gold Mine Co.,Ltd.encountered refractory gold ore in the production process,which led to the decline of production index and loss of operation.In order to ensure the continuous and stable follow-up production,In this paper,the recovery process of refractory ore gold in Guangnan Gold Mine Co.,Ltd.is studied and applied.The study of process mineralogical has shown that pyrite has been identified as the primary carrier mineral for gold(Au).Through the analysis of the nesting size and dissociation degree of pyrite and toxic sand,it is difficult to recover gold(AU)whether flotation or leaching process is used.According to the gold deposition status,a large number of process experiments have been carried out,adapting the alkali leaching pretreatment-cyanidation processing,the gold leaching rate is 46.15%;using the flotation process,under the grinding fineness-0.043 mm content of 95%,the small closed circuit can obtain a 4.76% yield,gold grade 14.78g/t,gold recovery rate of 44.77% of concentrate.Both the cyanide leaching and flotation processes are less effective and more difficult to recover gold.At that time,the cost of beneficiation for both processes is so high that it is not economically feasible.Combined with the results of alkali leaching pretreatment-cyanidation test,after a series of column leaching test studies,the treatment of low-grade sulfur and arsenic ore was finally completed by simple pretreatment and low cost heap leaching technology,with a comprehensive recovery rate of about 48% and a profit of about 70 yuan per ton of ore,which ultimately achieved the profitability purpose.Through industrial experiments and the promotion of production process gradually optimize the production details,the production process gradually matured,the production index is stable,began a large-scale production from 2018 to 2019,the cumulative amount of ore processed 800,000 t,affected by the increase in gold prices,the cumulative profit of over 50 million.The pilot study and application of this project have effectively revitalized the stagnant resources of the Guangnan Laozhaiwan Gold Mine Co.,Ltd,improved the resource utilization rate and enhanced the competitiveness of the enterprise.