When handling difficult materials, such as sewage sludge or corrosive chemicals, heat exchangers can be particularly susceptible to fouling. Having previously looked at the general issue and different types of fouling which may be experienced, it is also useful to look at some of the specific fouling situations encountered by our engineering teams. Fouling can generally be divided into one of four categories: chemical fouling (including scaling), biological fouling, deposition (or sedimentation) fouling, and corrosion fouling. In all cases prevention is better than cure, but as each of these different types of fouling is caused by a different combination of chemical and physical reactions, prevention will take different forms. More >>