Abstract
Measurement of high concentrations of solids in a suspension and measurement of large particle sizes (>1 mm) in suspensions often present large problems. In this paper a new measuring technique is described, based on light backscattering. This technique may be used for monitoring a process in which rapid and large changes in particle size occur, or for controlling processes with large concentrations of small particles. Theoretical backgrounds of the method are also presented. The measuring apparatus is described and some results are given to illustrate its possibilities.