Sieving for Particle Size Analysis
Sieving represents one of the oldest and simplest techniques for particle size analysis, providing mass distributions over a wide range of sizes. The technique segregates a sample according to the size of the particles it contains by passing them through a series of fine mesh sieves stacked one on top of the other. The particle size distribution is then calculated by measuring the mass of particles retained on each sieve. In doing this it is assumed that, by shaking the sieve stack, particles are able to fall through the sieve stack until they are correctly distributed. This requires the stack to be shaken for significant length of time.
The time required to obtain accurate results, the poor resolution of the technique and the problems associated with particle agglomeration and sieve blockage, has led to sieving being replaced by techniques such as laser diffraction in most industries. Even so, it still represents a useful method of separating particles based on their size.