Inline monitoring of liquid multiphase systems

Precise inline process analysis, as an instrument for securing product qualities and enhanced process efficiency, nowadays often requires not only a temporal but also a spatial investigation of relevant physical process parameters. From the variety of available methods that allow for a tempo-spatial medium analysis, a tomographic approach based on capacitive and ultrasonic sensor arrays to monitor multiphase liquid mixtures in-line is discussed in the present contribution. The approach aims for the localization of variable phase boundaries and the physical characterization of spatially distributed phases. Favoring a real time processing a reduced number of transducers in combination with a fast linear modeling is used. Theoretical and experimental results of a layered 3-phase-system illustrate the potential and limit in physical resolution.