菱铁矿含量对铁矿石浮选指标的影响研究

Study on the Influence of Siderite Content on Iron Ore Flotation Indexes

眼前山铁矿中菱铁矿含量高,难以直接分选利用。为了实现眼前山铁矿石合理利用,采用化学分析、XRD等手段查明眼前山铁矿石与配矿用齐大山低菱铁矿石的矿物组成及铁物相。通过磨矿—磁选、浮选试验研究了眼前山铁矿石与齐大山铁矿石在不同配矿比例下精矿指标的变化规律。结果表明,眼前山配矿量低于45%、磨矿细度为-74μm占90%、混磁精矿中菱铁矿含量低于5.41%时,浮选过程基本不会受到影响,仍可以获得TFe品位大于65%、TFe回收率高于60%的精矿;当眼前山配矿量在45%~50%、混磁精矿中菱铁矿含量在5.41%~6.05%时,浮选环境已被菱铁矿严重恶化,精矿TFe品位若达到65%,TFe回收率则大幅下降;当眼前山配矿量高于50%、混磁精矿中菱铁矿含量高于6.05%时,出现精尾不分的现象,难以通过浮选进行选别。激光粒度测试分析结果表明,菱铁矿在磨矿过程中易泥化,产生的大量细泥容易罩盖在大颗粒矿物表面,阻碍浮选药剂的吸附,使得脉石矿物与铁矿物的疏水性差异变小,恶化浮选效果。

The content of siderite in Yanqianshan Iron Mine is high,which is difficult to directly separate and utilize.In order to achieve reasonable utilization of Yanqianshan Iron Mine ores,chemical analysis,XRD and other methods were used to identify the mineral composition and iron phase of them.By grinding-magnetic separation and flotation experiment,the changes in concentrate indexes of two ores under different ore blending ratios were studied.The results showed that when the ore content in Yanqianshan is less than 45%,the siderite content in the mixed ore is less than 5.41%,and the flotation process is basically not affected.The concentrate with a grade greater than 65%and a recovery rate higher than 60%could still be obtained with grinding fineness of-74μm accounting for 90%.When the proportion of Yanqianshan iron ore is between 45%and 50%,and the content of siderite in mixed magnetic concentrate is between 5.41%and 6.05%,the flotation environment has been severe-ly deteriorated by siderite.If the concentrate grade reaches 65%,the recovery rate will significantly decrease.When the ratio of Yanqianshan iron ore is higher than 50%and the siderite content is higher than 6.05%,the concentrate and tailings cannot be separated.Further the mechanism of deteriorating flotation of siderite through laser particle size tests was analyzed,and the re-sults showed that siderite is prone to mud formation during the grinding process,resulting in a large number of micro fine min-erals or even fine mud.These fine partical can easily cover the surface of large particles,hindering the adsorption of flotation reagents,reducing the hydrophobicity difference between gangue minerals and iron minerals,and deteriorating the flotation effect.