Compressed Air Filter: Filtration with Active Carbon & Depth Filtration

Estimated Reading Time: 2 minutes

November 18, 2020

In the next compressed air filter topic, we are discussing filtration with active carbon AND depth filtration. Find out how filtering through active carbons works and then read about depth filtration.

We believe the topics in this guide will give you the knowledge about compressed air and compressed air systems. Continue your journey to becoming a expert today!

Filtration with Active Carbon

Carbon filters graphic

When filtering through a bed of active carbon both oil vapors and certain gases are absorbed. The compressed air is thus odorless and tasteless.


Normally, the active carbon in a filter element soaks up oil to approximately 15% of the amount of carbon weight before it is saturated. When the carbon is saturated, the filter element is replaced.


This type of filter should always be preceded by a depth filter in which any oil drops are separated. The compressed air should also be dried by air-drying prior to filtration through active carbon.


Depth Filtration

Depth filtration graphic

Depth filtration separates oil and particulates from compressed air through a filter of glass fibers. Oil droplets become trapped on the fibers, the oil is pressed through them and eventually drained via a drainage valve at the bottom of the filter housing.


Solid particulates are caught between the fibers.


When the filter material has been saturated by pollution, the pressure across the filter falls and the filter element must be replaced. The filter separates the oil most efficiently when the air pressure has a low temperature (+20°C or less) and when the air velocity through the filter is correct.


Continue through our compressed air guide:
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