前倾直挡板搅拌槽叶轮转速对矿浆浓度的影响

The Influence of Impeller Speed on the Pulp Concentration of the Straight Forward Baffle

某矿业公司年产百万吨的大型矿浆搅拌槽为研究对象,采用CFD中κ-ε湍流模型和多重参考坐标系法(MRF),对前倾直挡板搅拌槽内的多相流场进行了数值模拟分析,并研究了叶轮转速对搅拌效果的影响。研究结果表明,在搅拌过程中叶轮周围流体会形成两个旋转相反的涡流,促进矿浆整体循环,叶轮周围矿浆搅拌剧烈,叶轮边缘流速最大。在搅拌槽结构尺寸、矿浆浓度等相同的条件下,叶轮转速为(30~35)r/min时矿浆搅拌理想混合区(浓度58%~62%)比例较高,达到最优搅拌效果。

A multiphase flow field in a large slurry mixing tank was simulated by usingκ-εturbulence model and multiple reference coordinate system(MRF)method in an straight forward baffle stirring tank with an annual production capacity of 1 million tons in a mining company,and the effect of impeller speed on the stirring performance was studied.The results show that the fluid around the impeller will form two swirling opposite vortices during the stirring process to promote the overall circulation of the slurry.Impeller around the slurry mixing violent,impeller edge flow rate of the largest.Under the same conditions,such as structure size of agitating tank and slurry concentration,When the impeller rotational speed is(30~35)r/min,the proportion of the ideal mixing zone(58~62)%is high,which can achieve the best agitation effect.