In-Line Particle Characterization

Abstract

The characterization of industrial slurries and emulsions has traditionally relied upon off-line measurements of particle size and shape. Recent advances in sensor technology have made it possible to implement in-line particle characterization on a number of industrial processes, including comminution, crystallization, and emulsification. This paper presents several recent applications of two in-line instruments developed in our laboratory: an ultrasonic instrument used to monitor particle size in slurries during milling operations and to determine droplet sizes in emulsions, and a new in-line video camera for observing the morphology of crystals produced in a commercial process.

Investigations on the Capability of the Statistical Extinction Method for the Determination of Mean Particle Sizes in Concentrated Particle Systems

“…Ultrasonic spectroscopy enables the determination of particle size distributions and concentrations in highly concentrated dispersion processes (up to 70% by volume) . The measurement method is utilized, among other things, for the process analysis and control of colloidal suspensions in milling, crystallization, and polymerization applications . A comprehensive overview of the state‐of‐the‐art and its application is given by Babick .…”

Ultrasonic wave propagation in concentrated slurries – The modelling problem

“…It is to be noted here that functions of attenuation versus frequency are relatively featureless and could be approximated by polynomials of order three or less. This implies that model convergence would be difficult to obtain if the candidate PSDs were specified by more than two parameters (see Scott et al [2,3]). Current practice is to specify a log-normal distribution in particle volume fraction or number density versus particle radius; this is parameterised by a median particle size and a distribution width expressed as a standard deviation in log-space, see [1].…”

Design considerations for Micro-Autonomous Underwater Vehicles (μAUVs)

“…The first approach is to avoid in-process measurement altogether, relying on laboratory data and information gleaned from pilot-plant [7]. The second method is to take limited 'spot' measurements at specific times and locations [8]. The final approach is to use some form of Industrial Process Tomography (IPT) for continuous measurements [9].…”