Measurement of Cake Thickness on Membrane for Microfiltration of Yeast Using Ultrasonic Polymer Concave Transducer

Abstract

An ultrasonic measurement method was applied to obtain information about the properties of cake formed on the membrane in microfiltration of suspensions of yeast. The microfiltration was carried out at low applied pressure in order to assess that the cake formed was incompressible. A spherically concave transducer made of piezoelectric films of a vinylidene fluoride-trifluoroethylene copolymer was adopted. The surface shape of the cake was found not to be flat by the reflection technique. An on-line method of measuring cake thickness was developed by using the transmission technique, and the results showed good agreement with data reported elsewhere.