Ecological approach of macro-fouling prevention and control in cooling systems

Biofouling is a very frequent and serious problem in the cooling systems of electrical power stations. An investigation is being carried out at the Doel nuclear power station to discover ways of combating micro-fouling. Micro-fouling is combated preventively and curatively using a combination of chlorine, biofilm wetting agent and dispersing agent. This treatment removes the slime layer, which can act as a primary attachment point for macro-organisms.In the study of the macro-fouling in the cooling circuits, a monitoring method was developed which uses artificial substrates to provide direct data on the colonization and growth of these organisms. On the basis of the data obtained, the treatment frequency for the prevention or combating of biofouling was modified and optimized with respect to environmental considerations. As a result of this optimized treatment biofouling has been greatly reduced