KWS High efficiency filter with partition

The High Efficiency Partition Filter (HEPA Filter) is a precision-designed air purification equipment, widely used in medical, industrial, household and other fields, which is specially designed for filtering tiny particles in the air. Its core structure consists of multi-layer fibre materials and partitions, which can efficiently capture particles with a diameter of 0.3 microns and above, and the filtration efficiency usually reaches over 99.97% or even higher.

Structural Design

The spacer of a spacer HEPA filter is its unique feature. Usually made of corrugated aluminium foil or cardboard, these partitions support the filter material like ‘ribs’ and separate the filter material into several uniform channels. This design not only increases the strength of the filter, but also ensures that the air is evenly distributed as it passes through, avoiding air ‘bypass’ and resulting in efficient filtration.

The filter material is usually made of ultra-fine glass fibres or synthetic fibres, which are layered on top of each other to form a dense “filter mesh”. When the air passes through, particles will be intercepted by the fibres, adsorption or inertial collision, and finally be firmly ‘locked’ in the filter material.

Principle of operation

The principle of operation of the HEPA filter is based on three main filtering mechanisms:

Interception effect: When particles flow with the air, they will be intercepted by the fibre material, especially larger diameter particles are easier to be captured directly.

Inertial collision: The air makes a sharp turn as it passes through the fibre layer, and larger particles are unable to change direction in time due to inertia, hitting the fibres directly and being captured.

Diffusion effect: For very small particles (e.g. below 0.1 micron), Brownian motion causes them to diffuse randomly and eventually be adsorbed by the fibres.