Keeping Compressed Air Clean

05th June 2013

Compressed air is a common and popular resource in the food industry. It has many applications in the processing and handling phases of production. Compressed air can be highly efficient but it is prone to becoming contaminated. As well as reducing efficiency and resulting in higher maintenance for your machinery, contaminated air also risks spoiling food products, wasting resources and slowing production.

Here’s a look at how compressed air gets contaminated, and the effects this can have on your operations.

What contaminates compressed air?

There are usually about ten different contaminates that can be found in compressed air, including water vapour, vaporous and liquid oil, and atmospheric dirt. None of these are desirable in food production environments. These can get into the air in a variety of ways.

Air naturally contains moisture, so it is hardly surprising that compressed air does too. Oil often ends up in compressed air because of the machines that are used to compress it in the first place. It is not true, however, that machines which are oil free will produce compressed air without any oil in them whatsoever. Oil is present in the atmosphere thanks to machinery and vehicles.

Why are these contaminates a problem?

Compressed air is often used to drive machinery. When this air is fed into machines, the contaminates it contains can affect them. Water vapour or droplets could cling onto surfaces, causing corrosion or rust over time. Particles of dirt or rust, entering areas at high pressure, can damage pipes and other pieces of equipment. Contaminated equipment needs to be replaced more often, and can also jeopardise the product, making it undesirable or outside health regulations.

Having oil in compressed air can also damage products, and lead to unwanted colouration and odour.

Stopping compressed air from becoming contaminated

A compressed air solution is to use filters which enable the removal of contaminates from compressed air. The filters are precision engineered to be able to remove tiny particles, some of which are smaller than the width of a human hair. There are different types and levels of filter to allow the accurate removal of the many different contaminates in compressed air, including water and oil as well as dirt.

In a filter system, the air first passes through a larger filter, or a series of larger filters, which remove the biggest particles, before moving on to a series of smaller filters that strain out smaller particles. Finally, filters remove the oil and water from the compressed air. The pressure of the compressed air is often changed to suit the ideal operating conditions.

Caring for compressed air filters

As their job is to acquire dirt and other contaminates, compressed air filters will need to be changed. The manufacturer’s instructions and your own operating conditions will dictate how frequently this needs to happen. You can also tell when certain filters need replacing because the pressure of the system will drop below a certain level.

To find out more about compressed air filters please contact, AFS Ltd today.