漂浮颗粒临界悬浮过程搅拌桨型优化研究

Optimization of impeller combinations in just drawdown of floating particles in a stirred tank

在中低黏度的牛顿流体中,通过机械搅拌将漂浮颗粒下拉进入液体中并实现固体溶解过程,在工业中有广泛应用。文中以黏度为60 m Pa·s的基础油为实验物系,对3种不同的固体胶块形式进行临界悬浮过程的研究,采用了5种不同桨型,2种不同操作方式,分别研究各种桨型的功率消耗、混合特性以及漂浮颗粒的临界下拉功率等参数。结果表明:为达到将漂浮颗粒下拉进入液相并进行高效混合的目的,推荐采用下压操作、功率准数较低的窄叶翼型轴流桨CBY,该组合桨相对于传统斜叶桨PBT、宽叶轴流桨WH及窄叶轴流桨MIG而言,临界悬浮条件下功率消耗低,功率消耗相同时混合时间短,即混合效率更高的优点,能够实现漂浮颗粒临界悬浮过程的高效搅拌目的。

Just drawdown of floating particles into the middle to low viscosity fluids using agitators were widely applied in the industrial processes. Foundation oil with low viscosity（ 60 mPa · s） and three different kinds of floating particles were used as the experimental materials. Power consumption,mixing time and just drawdown properties were measured with five impeller combinations in two operation conditions. The results show that the multi-stages CBY has obvious advantages over PBT,WH and MIG combinations because CBY combination can make drawdown the floating particles into fluid at lower power consumption and has shorter mixing time in given power consumption. CBY combination is recommended for the just drawdown of floating particles because of its high mixing efficiency.