Particle size analysis is an important process in many industries, ranging from construction to cosmetics. Learn more about the process of particle size analysis, and its importance in a person's life.
Particle size analysis
Particle size analysis has a wide range of applications. It is commonly used to establish various properties of rocks and soils, ranging from their physical qualities to their potential for chemical reactions.
Particle size distribution Particles in a powder (or even particles dispersed in a fluid) can be analysed to generate as a particle size distribution. This can take the form of a list of values, but is more commonly incorporated into a “best fit” mathematical function. The particle size distribution not only defines the range of particles' sizes present, but also the relative population of every size. Experts will often analyse the particle sizes within soils before beginning construction projects. Particle size can have a major impact on building foundations, influencing long-term stability and maintenance costs. Equally, smaller particle sizes have an overall larger surface area, meaning that they are more susceptible to chemical reactions. This must be taken into account when selecting structural materials.
Toner manufacturers Particle size is an important factor in other industries too. Toner manufacturers must be confident that the particles in their products are constant, and that there's no risk that will cause damage to printers and photocopiers. Similarly, widely varied particle sizes within cosmetics can generate uneven results when applied to the skin.
Methods of separation
Sieving process The instruments used to measure particle size vary enormously depending on the industry. For large amounts of materials, a basic sieving process is often employed. This involves continuous shaking through a sieve, until the amount retained becomes more or less constant. The equipment is cheap, and the results are easy for amateurs to interpret. The major issue is not being able to distinguish between particles too small for separation. Elutriation method A more accurate method of analysing particle size is to use an elutriation method. This involves a fluid (commonly air) moving cyclically at a precise speed. The particles are then introduced and will separate depending on their mass. Lighter particles will be carried by the current, whilst heaver particles will settle at the base of the container. Sophisticated machinery will allow the user to vary the fluid speed to separate particles to any chosen degree of accuracy.