某微细粒蚀变岩型金矿高效浮选新工艺研究

New High-efficiency Flotation Process for a Microgranular Altered Rock Gold Mine

某金矿已探明金资源量58t,远景储量有望达到100t。矿石性质为微细粒蚀变岩型矿,属难选金矿。经过多年的建设、工艺优化和技术改造,选矿处理能力达到4000t/d,浮选回收率由70%提高至81.5%。近年来,选矿指标难以有质的提升。为了提高该矿山的选矿指标,采用化学分析、MLA自动矿物分析仪、偏光显微镜、扫描电镜、人工重砂等手段,开展了原矿、精矿、尾矿工艺矿物学研究和磨矿分级、浮选作业工艺考察,分析出制约选矿工艺提升的关键技术难题,即原矿金嵌布粒度微细、泥质矿物含量高和旋流器底流金循环量大,造成微细粒金难以单体解离、已解离的单体目的矿物表面受到污染而随着浮选尾矿流失,是选矿指标难以有效提升的主要原因。为下步工艺优化研究和选矿厂技术改造指明了方向。

A gold mine has proven that the gold resources is 58 t, and the prospective reserves are expected to be 100 t. The ore is fine-grained altered rock type, which is a kind of gold deposit suffers flotation. After years of construction, process optimization and technological reformation, the mineral processing capacity reached 4000 t/d, and the recovery rate of flotation is increased from 70% to 81.5%. In recent years, it is difficult to improve the ore dressing indexes qualitatively. In order to improve the ore dressing indexes of this mine, a series of means including chemical analysis, automatic mineral analyzer (MLA), polarized light microscope, scanning electron microscopy and artificial heavy sand were applied. The technological mineralogy analysis of raw ore, concentrate and tailings were carried out, and examined the inspection of grinding classifi cation and flotation process. The key technical problems that restrict the improvement of ore dressing process are analyzed, that is, the fine grain size of the original ore inlay, the high content of mud minerals and the large amount of gold circulation at the bottom of hydrocyclone, resulting in the difficult for the fine-grained gold monomers to be dissociated, and the surface of the dissociated monomer is contaminated and lost with the flotation tailings, which is the main reason why the mineral dressing index can not be effectively improved. It pointed out the direction for the next step of technological optimization research and technological reformation of mineral processing plant.