厚壁组合线圈在磁选设备中的应用与实践

Application and Practice of the Combined Thick Coils in Magnetic Separators

磁选柱是一种新型高效的磁选设备,通过磁聚合-分散及旋转上升水流作用,使磁铁矿颗粒受到磁力和流体力的联合作用,能有效破坏磁团聚,分离出单体脉石和夹杂的连生体,提高精矿品位和降低SiO2含量。磁选柱的电磁磁系是由几组均匀电流密度厚壁线圈组合而成,通过线圈的有效配置,产生特殊的磁场。本研究从分析磁选柱的厚壁线圈入手,首先介绍了三种常规线圈的结构、电流密度特征及其功率因子的大小,然后以均匀电流密度线圈为例对线圈的组合方式进行了简要分析,在此基础上研究了磁选柱励磁线圈的磁场特性及分选原理。磁选柱应用在本钢南芬选矿厂铁精矿提铁降硅技术改造中,改造后精矿品位由67.50%提高到69%以上,SiO2含量由6.5%降低到4.5%以下,证实了其在磁铁矿选矿厂工艺流程中的巨大作用。

Column magnetic separator is a new type high efficiency magnetic separator,by a combined effect of magnetic and hydraulic forces exerted on the magnetic particles through magnetic agglomeration – dispersion and swirling rising flow,,it can effectively separate the liberated gangue and intergrowth particles so as to raise the iron grade and reduce the content of SiO2 in the concentrate.The magnetic system of column magnetic separator is composed of several groups of thick coils.Through the reasonable combination of the thick coils,specific magnetic field are produced.From the analysis of the thick coil of the column magnetic separator,the structure,the current density property and the size of power factor of the three kinds of conventional coil structure were introduced firstly,then taking the uniform current density coil as an example,the combination of the coils was briefly analyzed.Based on this,the magnetic field characteristics and separating principle of the excitation coil were studied.When the column magnetic separator was applied to the iron increase and silicon reduction of the iron concentrate in Bengang Nanfen ore dressing plant,the grade of concentrate was improved from 67.50%to 69%and the content of SiO2 was decreased from 6.5%to 4.5%,confirming that it plays a great role in the technical flowsheet of the magnetite concentrator.