If compressed air is contaminated and comes into contact with the final product, the quality of these products might be compromised. In this article we will explain how to easily remove these contaminants from your compressor system.
Modern fiber filters are very efficient at removing oil. However, it is difficult to precisely control the quantity of oil remaining in the air after filtration as temperature, among other factors, has a significant impact on the separation process. Filter efficiency is also impacted by the oil concentration in the compressed air as well as the amount of free water. Data stated in the filter specification always applies to a specific air temperature,usually 21°C.
The compressed air from the compressor is hot after compression, often at a temperature between 70–200°C. An aftercooler is used to lower this temperature, which in turn also reduces the water content. Today, this equipment is frequently included as standard equipment for a compressor installation. The aftercooler should always be placed directly after the compressor. The heat exchanger cools the hot air and then routes most of the condensation water, which would otherwise flow into the system, as quickly as possible. The aftercooler can be either water- or air-cooled and is generally fitted with a water separator featuring automatic drainage.
Most compressor installations are fitted with an aftercooler as well as a water separator, in order to separate as much condensation water as possible from the compressed air. With the right choice and sizing of the water separator, an efficiency of 80-90% can be achieved. The remaining water flows with the compressed air as water mist into the air receiver.
Oil in the form of droplets is separated partly in an aftercooler, condensation separator or a condensation tap and flows through the system with the condensation water. This oil/water emulsion is classed from an environmental point of view as waste oil and must not be drained off into the sewage system or directly into nature.