搅拌流场对微细粒赤铁矿絮凝体特性的影响

Effect of Micro-fine Hematite Floc in Stir Flow Field

微细粒矿物因为粒度较细使用常规的选别方法很难达到预期的分选效果,尤其是赤铁矿,赤铁矿由于其堪布粒度细,成分复杂成为世界公认的难选矿物之一。絮凝是解决矿物选别粒度的最直接的方法。本文以河北某铁选矿厂重选精矿为原矿样制取超纯赤铁矿,并对超纯赤铁矿样进行化学多元素分析,由结果可知赤铁矿纯矿物的的全铁品位为68.94%,纯度可达98.49%。以制取的超纯赤铁矿为研究对象,研究了不同搅拌槽形状、搅拌速度、作用时间以及轴向距离对絮凝体粒径和分形维数的影响,并通过计算絮凝体的强度和孔隙率说明絮凝体的特性。结果表明:搅拌槽形状为方形时,在搅拌转速为900 r/min,作用时间为3.5 min,轴向距离为2 cm的条件下能够得到絮凝体的粒径为35.44μm,分形维数为1.6589,絮凝体强度为1118.84 Pa/mm^2,孔隙率为51.70%。所得絮凝体密实程度较高,强度较好,为以后絮凝工艺的更深入研究提供了有力的依据。

Because of the fine-grained, using conventional sorting methods could not achieve the desired separation efficiency, in particular hematite, due to the Khenpo fine grain size and complex components, hematite becomes one of refractory minerals around the world. Flocculation is the most direct way to solve the mineral sorting granularity. In this paper, a Hebei iron ore concentrator gravity concentrate sample preparation for the ultrapure hematite, through the analysis of ultrapure hematite chemical element, it shows that the pure mineral hematite iron grade is 68.94%, purity is 98.49%.In order to understand the effect in size and fractal dimension of micro-fine hematite floc in differentsquare of stirring tank, stirring speed, action time and axial distance. Also through calculate strength and porosity of floc to describe properties of flocs this research put ultrapure hematite as the subject. The result shows when the stirring tank is square, it under the conditions of stirring speed is 900 r/min, action time is 3.5 min, the axial distance is 2 cm could get the floc whose particle size is 35.44 μm, fractal dimension is 1.6589, floc strength 1118.84 Pa/mm^2, porosity is 51.70%. The floc has a high strength and good compaction rate, providing a strong basis for depth study.