Powders in various industries

Powders are used in many industries. Think of pharmacy where an important part of the medicines exist or are made from powders. Numerous powders are also produced and used in chemistry. In addition, many powders are used in animal feeds for both pets and livestock. This includes not only additives such as vitamins and minerals that are added, but also products such as grains and soy that form the basis for animal feed.

Products that many people all over the world come into contact with on a daily basis are products that are in the supermarket. A large proportion of the products are there in powder form. Think of coffee, tea, soups, sauces, milk powder and spice mixes. In addition, there are many products where powders are used as a base, such as flour for bread, but also cocoa and sugar for chocolate bars. Many powders are also used as an auxiliary substance in other products, such as corn or potato starch in soups and sauces. But also fragrances, colors and flavors, preservatives and added vitamins are examples of powders that are used in countless products.

Not a day goes by without dealing directly or indirectly with powders. There are three reasons why products are converted to powders:

• Powder has a great ease of use,
• It is easy to process,
• The quality of the product is maintained in powder form.

All over the world the powder industry is growing thanks to the innovation of new powder mixes and the growth of world population and prosperity. But what exactly is powder? Powder is scientifically a solid made up of different particles with dimensions ranging from nanometers to millimeters. One gram of powder with an average particle size consists of as many as 100,000,000 particles.

In the practice of powder processing, the limitation of 1 mm does not apply. Granules and granulates are also processed in large quantities.

The different properties of powders

Different types of powder all provide different properties. The first distribution that we can make within the powder properties is the bulk powder properties in relation to the particle properties. In large quantities, other properties are relevant, unlike when a particle is viewed on its own. Think of it like this: bulk powder properties are the combined effect of particle properties.

Particles Properties: distribution, shape, particle density, abrasiveness, corrosivity, composition and internal structure,

Bulk Powder properties: flow properties, bulk density, mix quality, tendency to segregate, dust formation.

A second division that can be made within powder properties is based on three main classes:

Fundamental properties: moisture content, shape, surface composition, surface shape, size and distribution, molecule and microstructure, bulk density, and melting point,

Functional properties: flow property and compressibility,

Unwanted properties: dust formation, stickiness, caking and stains.

Fundamental properties depend on both the own material properties during and after processing, as well as the properties of the raw material. These properties therefore vary enormously, but they remain parameters for the functional properties of the powder. An example that everyone knows is the difference between sugar and powdered sugar.

Granulated sugar can be ground into a powder. Powdered sugar clearly has a different structure than granulated sugar and is used in chocolate, candy and ice cream, among other things. Because icing sugar melts faster in the mouth, sweetness is experienced more intensely. But the properties also change during processing. For example, granulated sugar has different flow properties, different bulk density, and a tendency to dust as powdered sugar.

To produce small particles from the liquid or solid bulk materials, the materials can be dried, grinded, crushed, sedimented, worn, pulverized or crystallized. The two most common methods of making powder from liquid are drying and crystallization. When the powder is obtained from the bulk substance, there are different terms for different sizes such as dust, powder, grains and granulates. Dust is the finest powder, so fine that it floats around during the process and cannot be processed. This is followed by powder, such as milk powder or dyes. Next come the grains and aggregates. Think of instant coffee, but also cats and dog food.