Many operators of open evaporative cooling systems, commonly referred to as cooling towers, have been asking—at the latest since the entry into force of the 42nd BImSchV—how recooling plants can be operated in the most hygienic manner possible. A key factor in this context is the colonization of surfaces by microorganisms within the cooling water system. In particular, the frequently used polypropylene fill packs in open evaporative cooling systems provide an enormous surface area that can serve as an ideal habitat for bacteria such as Legionella.
On the one hand, nutrients are continuously supplied via the ambient air; on the other hand, a humid environment with relatively low cooling water flow velocities prevails. For these reasons, such internals are very often covered with a biofilm, from which Legionella can detach and enter the remainder of the cooling water system. Since fill packs are essential for the functionality of open evaporative cooling systems, the question arises as to how the associated risk can be minimized without reducing system efficiency and thereby jeopardizing the processes to be cooled.
For some time now, so-called Sanipacking fill packs from ENEXIO have been available. These fill packs are equipped with an antimicrobial surface, without affecting the cooling of the process water. Laboratory tests have previously demonstrated that bacterial colonization on the surface of Sanipacking fill packs is strongly inhibited [1]. This applies not only to Legionella but also to overall biofilm formation. In light of these findings and the experience gained from daily industrial practice, Multi Kühlsysteme GmbH has decided to use these fill packs in the future.
For operators of open evaporative cooling systems, Sanipacking fill packs can be identified by their characteristic light-blue color, in contrast to standard black fill packs. Retrofitting existing open evaporative cooling systems is just as feasible as equipping new installations. Another advantage of using ENEXIO’s antimicrobial-coated fill packs is the certified proof that these components are not metabolizable—a question that has frequently arisen in the context of risk assessments for open evaporative cooling systems.
There are therefore numerous reasons in favor of using Sanipacking fill packs. Especially with regard to the 42nd BImSchV, their use significantly reduces the risk of Legionella contamination of process water. Should you have any questions on this topic, please feel free to contact us at any time. In combination with new water treatment options—such as cooling water catalysts or reactors—this enables and ensures the long-term hygienic operation of open evaporative cooling systems and industrial recooling plants.
