Achieving food quality through high compressed air qualityDecember 10, 2014 REDWIRE is news you can use from leading suppliers. Powered by FRASERS.
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Great care must always be taken when compressed air comes into contact with food, because compressed air is not clean by nature. Extremely strict requirements are stipulated for compressed air quality in the food and beverage industry. Adherence to them is important in order to ensure food safety, and reduce risks to consumers.
Festo has published a white paper entitled “Food safety: food quality through high compressed air quality” that includes information on compressed air preparation and compressed air quality classes, as well as filter cascades for typical applications.
The white paper explains that different compressed air qualities are required at different points within the production system. Consequently, a carefully thought-out concept is necessary for efficient use of compressed air preparation, which should essentially take the special requirements for the production of each type of food into consideration. A combination of centralized, basic compressed air preparation and decentralized auxiliary preparation is advisable.
In most cases, compressed air is used as pilot air to control valves, cylinders and grippers, for example. For this type of application, contamination only needs to be removed from the compressed air in order to protect the pneumatic components against corrosion and excessive wear. Class 7:4:4 is recommended in this case, which can be achieved by means of a central refrigeration dryer with oil trap and particle filter (40 μm).
Significantly higher levels of purity are required when compressed air is used as process air, (e.g., for blowing out moulds, or when it comes directly into contact with food). However, this is usually limited to specific locations. Decentralized compressed air preparation, as close as possible to the consuming device, is advisable in this case. Consequently, only the required amount of air is prepared to the higher purity level, thus resulting in energy savings. Close proximity of compressed air preparation to the consuming device also minimizes the danger of recontamination of highly purified air in the piping network, for instance with rust particles.
The white paper goes into more detail on this topic, providing recommendations and examples. For more information, contact Festo.