提高梅山铁矿磨矿产品粒度均匀性的试验研究

梅山铁矿选矿厂针对其磨矿产品粒度分布存在的“两头多、中间少”现象，联合江西理工大学开展了优化磨矿参数，提高磨矿产品粒度均匀性的实验室试验和工业试验。工业试验在梅山铁矿选矿厂4#系列进行，历时6个月。其间根据实验室试验和流程考察结果，结合现场生产经验，对钢球大小和配比、介质充填率、磨矿浓度、返砂比、分级溢流浓度等磨矿参数进行了全面优化。磨矿参数优化后，4#系列最终磨矿产品（二段分级溢流）在保证细度为-0.076 mm占70%左右的情况下，300~10 μm合格粒级的产率增加了18.05个百分点，-10 μm过粉碎粒级的产率减少了1.60个百分点。进一步在实验室条件下对优化后4#系列的二段分级溢流和未优化3#系列的二段分级溢流进行分选效果对比，结果表明，前者所获铁精矿的产率和铁回收率分别高出9.54和6.60个百分点。此外，磨矿参数优化后，4#系列的钢球消耗、磨矿能耗、磨机中矿浆温度以及磨机噪音均得到了不同程度的降低。综上所述，4#系列的磨矿参数优化成果应在梅山铁矿选矿厂全面推广。

Increasing Granular Uniformity of Grinding Product from Meishan Iron Mine

Aiming at the “more of the two ends，less of middles” distribution phenomenon of grinding products，Meishan Iron Mine Dressing Plant uniting with Jiangxi University of Science and Technology carried out both laboratory test and industrial test to increase the uniformity of grinding products by optimizing the grinding parameters. Industrial tests are processed in 4# series of the plant for six months. During this period，based on the results of the laboratory test and the process survey，the grinding parameters including the steel ball size and matching，medium filling rate，grinding concentration，sand returning percentage and concentration of overflow are entirely optimized，combining with field production experience. After the optimization，for the ultimate grinding products in 4# series (overflow of second classification) at the fineness of about 0.076 mm passing 70%: 300~10 μm fraction(qualified) yield increased by 18.05%，and -10 μm fraction(over grinding) yield decreased by 1.60%. Separation index comparison of second classification overflows from 4# series optimized and 3# series not optimized in laboratory conditions is carried out. The results show that the former iron concentrate yield and recovery are increased by 9.54 and 6.60% respectively. In addition，after optimization of grinding parameters in 4# series，steel ball consumption，energy consumption of grinding，temperature of pulp in mill and also the noise from mill running have been decreased to some extent. To sum up，the achievement of grinding parameter optimum in 4# series should be put into promotion in Meishan Iron Mine Dressing Plant.