Sedimentation in Particle Size Analysis

Abstract

Particle size analysis by sedimentation is one of the most important techniques of analysis. The principle is based on the fact that it is possible to draw conclusions about the geometrical dimensions (size) of the particles from the speed of their movement in a fluid. In the past many different apparatuses were developed. Nowadays, methods that allow quick, automatic measurement are most popular. This article consists of two general sections valid for all methods: the first concerns the undisturbed and disturbed movement of particles in a fluid at rest, and the second concerns the dispersion of solids in liquids. The methods described are divided in gravitational methods and methods used in a centrifugal field, respectively. Finally, the appendix gives a list of liquids and dispersing agents valid for measurement.