Sieving is an industrial process applied throughout main manufacturing sectors in order to:
– Clean a powder or granular product from undesired particles with bigger dimensions (i.e. lumps, insects, metal parts etc.) or with smaller dimensions (i.e. fine powder) than main valuable product;
– Separate a powder or granular product into groups according to particle dimensions, in order to identify and create different products;
– Dewater a liquid product by separating its solid content from water.
Why is sieving introduced in manufacturing processes?
There can be many reasons, like:
- Safety: sieving is required in order to make sure that undesired particles are not entering together with main product into production cycle. In specific industries like food, this application follows law requirements concerning food production safety. In other industries, like 3D printing, this application is necessary in order to guarantee final component quality.
- Quality: sieving can be an interesting option in order to identify and create different valuable products starting from a bulk ingredient. Particle dimensions can play a role in food, metal powder, construction and many other industries, where each product extracted from bulk can correspond to a different market opportunity.
- Recovery: the circular economy concept is triggering industries to rethink their production process and find ways to make it more sustainable; within this context, sieving can be a good opportunity to extract valuable product from waste and transform it into a new opportunity as a new product to be used or sold.
If we want to explain this more technically, we can refer to below chart, which shows a sample product volume by particle size (i.e. PSD = particle size distribution) and indicates according to required cut point(s) which sieving applications are identified: dedusting (main product is cleaned out from finer particles); safety screening (main product is cleaned out from bigger particles); classification (middle fractions of a product are extracted from bulk according to their particle size).