Flow structure of the dispersed gasphase in real multiphase chemical reactors investigated by a new ultrasound–doppler technique

Abstract

Abstract The flow structure of the dispersed gas phase within an aerated stirred tank reactor of pilot scale (600L) has been investigated by means of a new ultrasound reflection technique. A compact implementation of the new measuring technique is described in this article. It allows the investigation the flow structure of the dispersed gas phase in real multiphase flows within arbitrary large reaction vessels. Measurements have successfuly been performed even in complex biotechnological and chemical production systems. The measuring device exploits the Doppler–shift of ultrasound pulses upon reflections at the surfaces of moving bubbles. Only a single measuring probe needs to be introduced into the dispersion. Bubble velocity distributions can be obtained within a few minutes, even during production processes in highly viscous media. The device is simple to use, since it is fully automized by means of integrated microprocessors.