摘要
针对当前弱磁性矿物干式磁选存在微细颗粒间黏附、团聚现象严重、分离选择性差的缺点,研制了一种新型空气动力场强磁选机。以TFe品位为17.5%的赤铁矿-石英混合矿为研究对象,探究了空气动力场强磁选机对不同粒级赤铁矿分选的影响。试验结果表明,该新型磁选机显著强化了颗粒间的分散,大幅度提高了微细颗粒干式磁选的选择性。对于-0.038+0.015 mm粒级赤铁矿,与常规设备相比,在回收率相近的情况下精矿品位提高了20百分点;同时有效消除了-0.038+0.015 mm粒级石英在-0.15+0.074 mm赤铁矿表面的黏附现象,避免了细粒石英因黏附在赤铁矿表面而进入到精矿中,降低精矿品位。颗粒受力计算表明,空气动力场可以克服微细粒颗粒间相互作用力,改善磁选过程的选择性,但是同时需要耦合高磁场感应强度和磁场梯度,才能进一步提高精矿回收率。
A novel pneumatic magnetic separator was developed to address the adhesion and aggregation of fine weakly magnetic materials and improve the captured selectivity in dry conditions.A mixture sample of hematite and quartz with a TFe content of 17.5%was used as the feed to investigate the separation performance of the novel magnetic separator for the mixture with different particle sizes.The experimental results showed that the novel magnetic separator significantly strengthened the dispersion between particles and greatly improved the selectivity of dry magnetic separation of fine particles.For the−0.038+0.015 mm hematite particles,the TFe grade increased by 20%compared with the conventional system under similar recovery.In addition,the aerodynamic field can eliminate the adhesion of−0.038+0.015 mm quartz particles to the surface of the−0.15+0.074 mm hematite particles,thus preventing fine quartz particles from entering the concentrate and reducing its grade.Finally,force analysis showed that the aerodynamic field can overcome the interparticle interaction and improve selective separation,but a high gradient magnetic field was required to enhance the recovery of magnetic particles.
作者
胡志成
谢顺平
卢东方
HU Zhicheng;XIE Shunping;LU Dongfang(School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,Hunan,China)
出处
《矿产保护与利用》
2023年第5期71-80,共10页
Conservation and Utilization of Mineral Resources
基金
国家自然科学基金面上项目(52174270)。
关键词
干式分选
强磁选机
空气动力场
赤铁矿
石英
dry separation
high−intensity magnetic separator
aerodynamic field
hematite
quartz