Hygienic design in practice
A few simple rules can improve the cleanability of a process line. But how does this translate into practice? Below some ideas for the main components of a process line, the tanks and pipes, but also the Cleaning-In-Place (CIP) system itself.
- Avoid sharp edges, crevices and openings to reduce the risk of accumulating dirt and no optimal circulation of the cleaning liquid
- Place components (valves, instruments, etc.) as close to the tank bottom or at the top bracket: the farther they are removed from the tank surface, the more difficult for the cleaning liquid to make contact with all the corners and edges. Conical connections are easier to clean than rectangular.
- Choose the correct spray ball(s) and position them so that the cleaning liquid reaches all the components, including connectors.
- Avoid sudden splits or large variations in the diameter of the pipes. In this way, speed traps are prevented and the circulation speed is maintained at the right level.
- Often process lines that are no longer in use, are not removed. Or lines are already installed for future extensions. In such dead zones a lot of dirt can accumulate. In addition, the cleaning fluid can not circulate in an optimal way.
- Choose the right valves and keep in mind that seals can fail. In a double-seat valve seals are perfectly cleanable. If one of the gaskets fails, the leakage is separated through the a seperate and specially designed discharge, without the mixage of different products. The drain acts as a visual leak detection.
The hygienic design is primarily to make the process line better cleanable. The level of hygiene of the CIP system itself, however, is thereby often overlooked. As a link in the whole cleaning process, the CIP itself also has an impact on the hygienic quality of your process line.
- Be critical for recovery of old CIP tanks: make sure to check whether they still meet the current requirements in terms of hygienic design. This is in particular important for the final rinse tank, where the final rinse water should be at least drink water quality.
- Avoid the alkaline or acidic solution to contaminate your rinse water: Use preferably double butterfly valves or double seat valves on the pipes of the rinse water.