Rouge in WFI-systems
(Mat. 1.4404/1.44305/316L)
Temperature sensor

Tube system

Pump wheel
After operation times of 6 – 12 months the internal surfaces of these systems often show reddish brown, rust coloured surface contaminations which can usually be verified when wiping with a white cloth.
It normally concerns heavy metal particles which result from a change of the stainless steel surface the so called rouging.
Connected production systems such as fermenters, batching tanks, mixing vessels and tube systems are then contaminated in undesired form by displacement of the rouge particles.
Even by regular CIP-cleaning of these systems the heavy metal particles cannot be removed.