A Quantitative Study of Drop Coalescence in Stirred Dispersion

搅拌分散中液滴聚结的定量研究

• 批准号: 9020320
• 负责人: Doraiswami Ramkrishna
• 金额: $ 15万
• 依托单位: Purdue Research Foundation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-06-01 至 1993-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9020320&HistoricalAwards=false
• 关键词: Quantitative; Study; Drop; Coalescence; Stirred

This project is an investigation of several effects on drop coalescence in stirred liquid-liquid dispersions which may be used effectively to control drop populations. Thus the effect of surface charge on droplets and its manipulation by various means on coalescence phenomena is investigated experimentally and theoretically. The manipulation of surface charge effects are accomplished by addition of electrolytes and surfactants, and by varying the pH of the medium. The effect of turbulence intensity on drop coalescence is investigated as a method to control drop sizes by energy input to the dispersion. Since most industrial liquid-liquid contacting operations involve high dispersed phase fractions, the project investigates dense dispersions by exploiting self-similar behavior and scaling properties. The approach presented in this work is unique in that information will be obtained at the individual droplet level so that coalescence rates are obtained as functions of drop sizes in addition to their dependence on other physical parameters. The effects proposed for study in this work are either completely unknown or are at best ambiguous as obtained from studies insensitive to drop size distributions. It is important to understand the foregoing effects in order to control dispersed phase systems so that contacting operations can be performed optimally with respect to conversion and selectivity.

该项目是对跌落的几种影响的调查 在搅拌的液-液分散体中的聚结， 有效地控制了水滴的数量。 因此， 液滴表面电荷及其操纵的各种 对聚结现象进行了实验研究 理论上也是 表面电荷效应的操纵 通过添加电解质和表面活性剂来实现， 并通过改变培养基的pH值。 湍流的影响 研究了液滴聚结强度作为一种方法， 通过输入分散体的能量控制液滴尺寸。 以来 大多数工业液-液接触操作涉及 高分散相分数，该项目研究致密 利用自相似行为和缩放的色散 特性. 这项工作中提出的方法是独特的，因为 将在单个液滴水平上获得信息 从而获得作为液滴函数的聚结速率 除了它们对其他物理特性依赖之外， 参数 在这项工作中提出的研究影响是 要么完全未知，要么最多是模糊的， 对液滴大小分布不敏感的研究。 是 重要的是要了解上述影响，以便 控制分散相系统， 可以在转化方面最佳地进行， 选择性