Particle size control using light-scattering technology
The increasing importance d particle size measurement in industrial processes, combined with escalating labor costs and the need for increased energy efficiency, has led to the development of faster, more precise analytical methods. Of these new methods, light scattering has grown the most rapidly. Light-scattering instruments use lasers to illuminate a flowing stream of particles. The resulting diffraction patterns are then processed optically and electronically to measure various parameters of the particle size distribution. This article discusses the importance of particle size control and measurement in industrial processes and explains the principles of light-scattering technology.
Measurement of particle size for its own sake is of little value. Size information must be obtained for a purpose to be useful. Process control is often the sole justification for measuring one or more particle size parameters. The mean particle size, the percent passing a given size, or the surface area can be related to good and bad product. In these cases, the ability to maintain the size parameter within a predetermined specification ensures good product output.