How do we measure particle size?
Dynalene uses several different techniques to measure particle size, depending on your sample properties. We can measure particles from a few nanometers to several microns. The types of samples we can analyze and the instrument we use to measure them are detailed below:
Particles suspended in solvent
Particle size range: 5 nm to 2 micron
For nano- and micron-sized particles suspended in a solvent, we use a Nicomp particle sizer. This instrument relies on the technique of dynamic light scattering (DLS) to provide a size distribution profile. Our Nicomp can measure particles ranging from a few nanometers to 2 micron.
Essentially how this works is a laser is positioned at a small vial containing the particles in suspension. As the laser travels through the vial, light is scattered in different directions by the particles, which is eventually picked up by a detector. The particles in the suspension are not stagnant though – they are constantly moving randomly in the liquid known as “Brownian motion”. Because of this, they will continuously scatter light in many different directions over time.
Think of the detector as a big screen that can collect dots of light. The particles will deflect light to different areas of the detector screen, so what we have as a result is a unique speckled pattern of light dots. If the Nicomp were to send many “bursts” of the laser through the vial over a short period of time, the detector would project a different speckled light pattern for each burst due to the Brownian motion of the particles. By projecting many patterns with different spots of intensity and determining the distances between the light spots, this information can be applied to a mathematical distribution, which eventually can be correlated to particle size.
Particles in a solid mixture
Particle size range: 38 micron to 1 millimeter
Dynalene can also perform particle sizing for solid mixtures containing several different sized particles. We can provide particle distributions (base on percent of solid mixture) for products like dirt, soils, and milled powders. Our sieve system can analyze particle sizes ranging from 38 micron to 1 millimeter over 20 stages, and corresponds to the ASTM E-11 standard.