FOR MANY decades, the massecuite brix in vacuum pans has been controlled using
simple and cost effective conductivity probes. Despite their widespread use, they suffer
from a variety of problems, including temperature sensitivity and changes in impurity
loads. Arguably, conductivity probes are not highly process relevant, since they deliver
at best only an indirect measure of fundamentally important process variables. This
paper presents results from a series of industrial trials using a microwave-based
instrument. It presents an overview of the installation and use of this class of device for
effective batch vacuum pan control. Experimental results from a series of trials run on a
100 tonne batch vacuum pan are presented.