Quality of air is a pressing issue and there have been many instances where people have ordered filters not knowing what it is they actually need. As cars need different types of tires for different types of terrain, a car driving in snow will have a tire with more grip than the same car driving on a paved pathway, so do compressor systems require different filters for the different uses. The following is each type of filter and what it is used for:
Particulate filters are used to remove dust and particles out of the air. This will allow air to travel faster in the piping system and prevent clogs. The main element in this filtration is the membrane. The membrane acts like a gate which only lets air pass through while anything bigger gets blocked by the membrane material.
Coalescing filters are used to capture oil and tiny moisture droplets and prevent condensate from developing in the system. This will prolong the life of the piping system and other components by avoiding rust. The main component used is the flow of the air. The filter may contain a membrane element in it as well but altering the flow of the air in a tight space causes condensate or oil to gather at the bottom of the filter.
Activated Carbon Filters
Activated carbon filters are used to remove odors and vapors. These filter are mainly used for food processes and or where breathing air is produced. Carbon is used to absorb contaminates and due to a high surface area it is very effective at doing this task. As air passes the carbon all contaminates will be attracted to this surface area and rest there as opposed to remain mobile in the air stream.
Also keep in mind that a high quality air filter will have a lower pressure drop while filtering the air which goes through it. As time passes dust and other materials will accumulate in the filter and increase the pressure drop which results in more cost and less productivity. Remember to change the filter element as needed.