Continuously driven circulation systems like cooling systems or supply systems for water-based metalworking fluids always have an increased risk of microbiological contamination. As long as the contamination is within the main body of the system and in the bulk of the liquid, the detection of the microorganism e.g. by mikrocount® is quite easy and the system can successfully be treated at an early stage with grotan® or parmetol® biocides.
In reality the situation is unfortunately often more complex. This is mainly due to the fact that the supply system for cooling fluids often contains lengthy pipe systems with different diameters, changing fluid flow and very often with so called dead ends/dead spots, areas with nearly no fluid movement. These areas are prone for sedimentation of microorganisms. This is the starting point of biofilm formation.
Microorganisms in biofilms are well protected against the environment and biocides because they are covered by a slimy gel.
Biofilms cause repeated recontamination of circulation systems. They can only be destroyed by mechanical measures, often not applicable in piping systems, or by the use of efficient antimicrobial system cleaner e.g. grotanol® products. grotanol® products combine the properties of an excellent cleaner to break the slime and remove the film with those of a biocide to destroy the microorganisms released out of the biofilm.
Production equipment used in almost any production environment can have comparable issues. The main sources of contamination are often tubing and automatic dosing systems for the manufacturing of raw materials where biofilm formation is prevalent. Relatively long dwell periods of >3hours can lead to high germ counts and consequently to the formation of biofilms.
To ensure safe and sustainable removal of biofilms from the system, schülke recommends before cleaning circulation systems or production use of grotanol® system cleaner. Just as existing biofilms can be chemically broken down, flushed out and the surfaces of the pipes to disinfect the system sustainable.