油包水型乳化液剪切破乳的实验

通过设计Couette双圆筒装置形成薄层纯剪切流场,其剪切强度可通过内筒转速调节,对油包水型乳化液剪切破乳的可行性进行研究。从流体动力学角度分析单个液滴受力,建立其仿射形变模型并经实验验证,与TaylorGI和CoxRG的理论模型基本一致。实验结果表明,将剪切作用引入流场中有利于液滴聚合,当内筒转速为50~150r/min(剪应力8.67~26.01Pa)时,液滴最大直径和平均直径比未引入剪切力场时高,说明只有在一定剪切范围内,剪切才能促进液滴聚合。因此,为了提高油水乳化液分离效率,可在油水分离设备中引入适当的剪切力场。

Experiment on Shearing Demulsification of W/O Emulsion

In order to study the feasibility of the shearing demulsification of W/O emulsion, a Couette double-cylinder device was designed to form a lamina flow, and its shear intensity was controlled by the rotate speed of the inner cylinder. The force of single droplet is analyzed according to hydrokinetics, and the affine deformation model is put forward and validated by experiment which basically agreed with Taylor G I and Cox R G theory. The results show that shear is propitious to droplets aggregation. Based on the relation curve of droplets diameter with the revolution of inner cylinder, it was found when the rotation velocity of inner cylinder is 50~150 r/min ( shearing strenghth of 8.67~26.01 Pa), the maximal diameter and average diameter are all larger than that of droplets which are not in shear flow. It was shown that shear can accelerate droplets aggregation only within a valid shear range. Therefore，a proper shear flow can be introduced into the separate device to improve the separate efficiency of W/O emulsion.