Abstract: Considering size distribution of dispersed droplets, the motion of dispersed droplets in W/O emulsion was simulated in a demulsification process under high electrostatic voltage.The results from simulation and experiment showed that under the effect of electrostatic electrical field, the droplet group moved from one electrode to the other electrode, so that the local droplet concentration increased gradually along the motion direction and the concentration reached a maximum value in the vicinity of the other electrode.The droplet concentration in the vicinity of electrode approximately linearly increased with the time of electrostatic action.The rate of increase of droplet concentration in the vicinity of electrode under a higher applied voltage was larger than that under a lower applied voltage in same time interval.To improve demulsification efficiency by increasing voltage was therefore superior to that by extending time.In addition, since the large droplet had a relatively larger velocity, the demulsification efficiency for the emulsion with large dispersed droplets would be higher.

Key words: W/O emulsion, electrostatic coalescence, dispersed droplet, motion characteristics

摘要： 考虑乳化液离散液滴的直径分布,对高压直流静电破乳过程中离散液滴的运动进行了理论模拟。模拟及实验结果表明,在高压静电作用下,离散滴液从一侧电极向另一侧电极运动。沿液滴运动方向,液滴浓度逐渐增大,并在电极附近达到最大。随着静电作用时间的延长,电极附近液滴浓度近似呈线性规律增大。在相同的作用时间内,高电压液滴浓度的增长幅度要更大。因此,尽可能提高施加电压要比单纯延长静电作用时间的破乳效果更好。此外,大的液滴运动速度更快,故对于离散相滴径较大的乳化液,破乳效率会更高。

关键词: 油包水乳化液, 静电破乳, 离散液滴, 运动特性