从某石棉尾矿中粗粒干式预选的铁粗精矿选矿试验研究

Beneficiation Test of Coarse Iron Concentrate Obtained from the Coarse-particle Dry-preconcentration of Asbestos Tailings

某石棉尾矿干式磁选预富集粗精矿类似于贫磁铁矿石,但具有矿石易吸水、矿浆黏滑、磨矿分级难度大等特点;TFe品位32.46%,主要铁矿物为磁铁矿,磁性铁含量30.85%、分布率为93.48%;脉石矿物主要是蛇纹石和石英,化学组成中二氧化硅和氧化镁含量较高,是要去除的主要杂质成分。为了确定试样的磨选工艺流程,采用湿式预选、阶段磨矿、单一磁选工艺流程进行了选矿试验,在一段磨矿细度为-0.074 mm60%~65%,二段磨矿细度在-0.043 mm85%情况下,一次湿式预磁选、1次脱水槽浓缩脱泥、1次弱磁粗选、2次弱磁精选,可获得精矿TFe品位为58.43%、回收率为89.84%的铁精矿。推荐的湿式预选、阶段磨矿、单一磁选工艺流程简单,具有对矿石性质变化的适应能力强,选矿成本较低的特点。

The preconcentration coarse concentrate obtained from the dry magnetic separation for as⁃bestos tailings is similar to low-grade magnetite ore.While it is with features such as easy to adsorb water,pulp stick-slip and hard to grind and classify.The TFe grade of the products was 32.46%and the main iron mineral was magnetite ore with magnetic iron content of 30.85%and distribution rate of 93.48%.The main gangue minerals are serpentine and quartz.The content of SiO_(2) and MgO in the ores was high,which were the main impurities need to be removed.In order to determine the grinding and beneficiation flowsheet,the beneficiation test were carried out with wet preconcentration,stage grinding and single magnetic separa⁃tion process.With grinding fineness of-0.074 mm accounting for 60%~65%and-0.043 mm accounting for 85%for the first stage and second stage separately,the iron concentrate with TFe grade of 58.43%and recovery rate of 89.84%was obtained by once wet preconcentration magnetic separation,once thickening and desliming using dewatering tank,once low-intensity magnetic roughing and twice low-intensity mag⁃netic cleaning.The recommended process including wet preconcentration,staged grinding and single mag⁃netic was simple,and has good adaptive capacity with the variational ore properties,appearing low benefici⁃ation cost.