Microfibre Filter Elements Coalescing principle

Coalescing Principle

Our microfibre glass filter elements are designed to follow the coalescing principle. The goal is to remove aerosols and dust particles from the air stream. To achieve this, our filter elements have a number of glass fibre layers inside. These fibres are distributed randomly and oriented in all directions. Aerosols and dust particles are much smaller than the media pores which means that no sieving occurs. Three different mechanisms take place where each is responsible for capturing particles of a particular size. 

Filter Element with particles
Crosssection microfibre

a) Inertia impaction

The first mechanism is inertia impection. Large particles (light blue) do no follow the gas flow stream lines because of their large inertia. They flow straight and collide directly with the microfibres. Inertia impaction becomes more important with increasing particle size. 

b) Interception

Interception occures with aerosols and particles with smaller size. They are light enough to follow the stream line but will hit the fibre when the radius of the particle is larger than the distance between the stream line and the edge of the fibre. It gets stuck there and gets removed from the air. Interception gains more importance with increasing particle size.

c) Diffusion

Diffusion takes care of the smallest particles. These small particles do not strictly follow the stream lines. They follow the brownian motion and move randomnly due to collisions with gas molecules. Because of this movement they are likely to collide with the fibres. The smaller the particle is the higher its freedom of movement and therefore the higher their probability to encounter a fibre. Captured by diffusion becomes more important with decreasing particle size. 

The total filter efficiency is the result of the combination of these three filtration mechanisms.

total filter efficiency

Get in touch and let us discuss if we can help you with our solution for your specific application. We look forward to helping you. 

Don´t be afraid to tell us about your project´s timeline and budget.
We´re straightforward with our abilities and pricing, and knowing where you´re coming from helps us hit the target.