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Particle size analysis, particle size measurement, or simply particle sizing is the collective name of the technical procedures, or laboratory techniques which determines the size range, and/or the average, or mean size of the particles in a powder sample.
Particle size analysis is part of Particle Science, and its determination is carried out generally in particle technology laboratories.
The particle size can have considerable importance in a number of industries including the chemical, mining, forestry, agriculture, and aggregate industries.
* When one of the reactants is a powder, or when in a chemical reaction the catalyst is in a pulverised state, either in a fixed bed, or in a fluidised reactor.
The Particle Technology Forum, an international and interdisciplinary forum, but also a division of the American Institute of Chemical Engineers says: «…particle technology — that branch of science and engineering dealing with the production, handling, modification, and use of a wide variety of particulate materials, both wet or dry, in sizes ranging from nanometers to centimeters… spans a range of industries to include chemical, petrochemical, agricultural, food, pharmaceuticals, mineral processing, advanced materials, energy, and the environment»
There are a large number of methods for the determination of particle size, and it is important to state at the outset, that these different methods are not expected to give identical resülts: the size of a powder depends on the method used for its measurement, and it is important to choose that method for its determination which is relevant to its use.
The size of materials being processed in an operation is very important. Having oversize material being conveyed will cause damage to equipment and slow down production. Particle-size analysis also helps the effectiveness of SAG Mills when crushing material.
Particle-size analysis in the agriculture industry is paramount because unwanted materials will contaminate products if they are not detected. By having an automated particle size analyzer, companies can closely monitor their processes.
As mentioned in the post, mineral grinding facilities utilize sieves for the initial and intermediate processing stages and all finished products must pass quality control procedures using particle size analysis instrumentation. These quality control procedures are a must for a variety of end users (Paint, Plastics, Lubricants, Personal Care) that require particle size process control for their manufacturing/blending process.
In the paint manufacturing process, pigments, fillers, resins, and solvents are blended to make many different types of paints. Pigments and fillers, such as Titanium Dioxide, Calcium Carbonate, Clays, Talc, etc. are typically used. The paint manufacturing process begins with a grinding process to further reduce the particle size of the pigments and fillers to meet the desired specifications of the finished paint. The particle size is closely monitored to make sure the specifications for gloss, opacity and overall appearance is achieved.
Filtration and separation techniques are widely used in many manufacturing processes. Typically they are used to remove unwanted contaminates, but they are also used to capture recyclable materials, such as precious metal catalyst. Either way it is important to understand the particle size of the suspended solids, as well as the total suspended solids (mg/l) to choose the appropriate micron size filter and vessel. A properly engineered filtration system will keep your process running smoothly and minimize unnecessary downtime. Particle Analysis is crucial in the system design and filter selection.
When running samples which are heavily loaded with solids or when dispersing a powder/solid in water (or other carrier) it may be necessary to properly disperse the solids using a ultra sonic mixer prior to the particle size analyzer. A noise controlled room is usually best because they can be quite noisy.