POWDER MIX SEGREGATION

When you are moving, pouring, conveying or processing materials, each step can affect product quality. The product can become un-mixed so that there is no longer the same proportion of ingredients in each of the consumer consumption units (or ‘doses’ to put it another way).

In some market sectors this may not matter too much, for example you could sometimes tolerate occasionally getting a drink that is a bit too sugary or not flavored enough. But for some products that contain vitamins & minerals it is vital that the correct amount reaches the consumer – in this instance there is no doubt the importance of avoiding the breakdown of an homogeneous mixture.

In order to provide high quality, high functioning products, modern recipes often use a variety of different powder types, all of which have different particulate characteristics. Separation of a mixture is caused by the differences in size, shape or density of the powder particles. 

Particle size is probably the most significant source of segregation. When transferring product between processing steps, the in-flight material will travel at different velocities depending on particle size, this creates what is known as trajectory segregation. Larger particles will be projected further, leaving the smaller ones behind.

A further cause of segregation is percolation. The small particles move downwards through the mass falling into the spaces between the larger particles. It occurs during shaking, or vibration of the hopper when charging or discharging its contents. At the same time, the larger particles move upwards in the so called ‘Brazil Nut effect’ as voids are created then filled in with the smaller particles forcing the larger particles upwards. These changes in powder state often occur unknowingly through traditional handling methods.

Matcon IBCs are designed to create mass-flow of powders due to their 60° hopper angle, smooth interior surfaces and unique Cone Valve technology.  Mass-flow is defined as all the powder is in motion across the whole of the container whenever any is withdrawn.  It produces a first in-first out flow sequence, eliminating any stagnant areas, and providing a steady discharge with consistent bulk density, and a flow that is uniform and well-controlled.

This keeps the mix homogeneous during the discharge process and helps to maintain product quality.

Discover the Cone Valve with this helpful video.