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Version: 20221219
A typical CIP routine for processes with organic material could consist of:
1.
Drain for product
2.
Flush the system with 55 °C water
3.
Caustic wash, 55 °C at pH 11-11.5 for 20-25 min
4.
Flush with water for 5 min
5.
Between each step the system can be drained.
Sometimes an acidic step may be required, this could consist of:
6.
Acidic cleaning solution at pH 1.5 for 15-20 min
7.
Flush with water for 5 min
Note that membranes have different pH tolerances and the CIP cleaning regime should be
selected accordingly. For some applications enzymes, oxidizing agents or detergents may help
the cleaning process.
H.
Clean water flux
After cleaning the membrane, the clean water flux should be measured. By comparing the
clean water flux after each cleaning cycle with the original membrane performance it is
possible to determine if the cleaning regime is sufficient to ensure a good recovery of the
membrane.
The clean water flux should be compared by using at the same reference parameters (same
transmembrane pressure and a standard water temperature, typically 25 °C). If the water
temperature deviates the measured water flux can be normalized to the standard
temperature using a temperature correction table.
A recovery of 80% or more of the initial water flux should be expected from a good cleaning
regime. However, it is equally important to monitor the trend of the clean water flux in order
to evaluate if the cleaning regime is efficient and sufficient.