Ultrasonic Monitoring of Creaming

The practical measurement of creaming is hindered by the opacity of most emulsions. If there is any variation of the speed of the droplets during creaming, due to polydispersity or density variation, the slower-moving fraction obscures the movement of the faster droplets. Analysis of creaming rates thus needs a knowledge 

The emulsion, held in a rectangular perspex cell, is installed in a thermostated water bath. A carousel holds up to five such cells and rotates, under the control of a 

Measurements of time-of-flight are made at many heights in a sample to define a profile of ultrasonic velocity with respect to height in the emulsion. A scan defines 

Below we describe the use of the ultrasonic monitor to detect creaming in a polydisperse concentrated emulsion, and to characterise flocculation from the creaming behaviour. The effects of added polymers on the flocculation and creaming processes are also described. 

3 Creaming of Polydisperse Emulsions iivithout Added Polymer 

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