贵州某重晶石矿X射线预选—浮选试验研究

Experimental Study on X-ray Pre-concentration-Flotation of a Barite Ore in Guizhou

贵州某重晶石矿原矿BaSO4含量为70.82%,主要脉石矿物为白云石、长石等,重晶石粒度极不均匀,且与脉石矿物嵌布关系复杂。选矿试验结果表明:重选难以获得理想的选矿指标,对-30+15 mm粒级样品采用X射线智能分选机预选抛尾,抛废率为11.07%,预选精矿合并到-15 mm粒级样品,在磨矿细度为-0.075 mm含量90%的条件下,经一次粗选三次精选的浮选工艺流程,最终获得了BaSO4品位92.93%、综合回收率83.51%的选别指标,重晶石精矿密度为4.34 g/cm^(3),达到了钻井液用加重剂特级品标准。与采用常规“磨矿—浮选”工艺流程相比,采用X射线预选工艺在最终精矿回收率相当的情况下,精矿品位提高了1.11百分点,且减少了磨矿浮选作业处理量,具有良好的推广应用价值。

A barite ore in Guizhou contains 70.82%BaSO4 with dolomite and feldspar being the main gangue minerals.The grain size distribution of barite is extremely uneven,and the association between barite and gangue minerals is complex.Beneficiation tests revealed that the gravity separation was not effective.As a result,the process flow of"particle classification—X−ray pre−concentration—flotation"was adopted.The X−ray intelligent separator was applied in pre−concentration operation to remove gauge particles for−30+15 mm of the raw ore,resulting in a discarding rate of 11.07%.The pre−concentration concentrate combined with−15 mm particle size samples was treated by the flotation process of one roughing and three cleanings under the grinding fineness conditions of−0.075 mm 90%.The separation indexes of barite concentrate with a BaSO4 grade of 92.93%and a comprehensive recovery of 83.51%was finally obtained.The density of the concentrate was 4.34 g/cm^(3),meeting the standard for a special grade weighting agent for drilling fluid.Compared with the conventional process of"grinding—flotation",the X−ray pre−concentration process improved the concentrate grade by 1.11 percentage points and reduced the processing capacity of grinding and flotation operations without affecting the final concentrate recovery rate.Hence,the pre−concentration technology exhibits good promotion and application value.