This work deals with process monitoring. In particular, the process of used-sand regeneration is monitored with the aid of impedance spectroscopy and can be controlled in the future with the measurement data obtained in this way. This results in the following aspects: a consistently high quality of the process material is realized by a controlled process. At the same time, energy consumption is minimized. The result is a process that is both more resource-efficient and more economical.

This paper presents an explosion-proof two-channel Raman photometer designed for chemical process monitoring in hazardous explosive atmospheres. Due to its design, alignment of components is simplified and economic in comparison to spectrometer systems. The described embedded sensor is ideally suited as a process analytical technology (PAT) tool for applications in environments with limitations on power input.

The paper shows how the precise knowledge of the sound field of an ultrasonic annular array can contribute to the development of novel measurement techniques. It demonstrates the locally resolved measurement of sound velocity in fluids, simultaneous measurement of thickness, sound velocity of layers and curvature. To demonstrate the methods, the principles as well as results of simulations and measurements are discussed.

A concept to measure in situ sulfidation of silica pellet catalysts loaded with nickel is evaluated. During sulfidation between 100 and 400°C nickel sulfides form. The electrical impedance of the pellets was recorded in situ. At first, the particles are highly insulating but during sulfidation their conductivity increases by decades. Since nickel sulfides are less conductive than nickel, the strong conductivity increase may be due to conducting percolation paths that form during sulfidation.