Why must heat exchangers in condensing heat recovery systems be resistant to corrosion?

The need for heat exchangers in condensing heat recovery systems to be resistant to corrosion primarily stems from their exposure to high sulphur condensate. Condensate that contains high levels of sulphur can create a highly corrosive environment, especially when combined with moisture and other operational factors. Sulphur compounds can lead to the formation of acidic conditions, which significantly increases the risk of corrosion in metals if not appropriately accounted for.

Using corrosion-resistant materials in the construction of heat exchangers is essential to prolong their lifespan and maintain efficient operation. This resilience helps prevent leaks and failures, ensuring that the system remains effective for heat recovery and does not incur additional maintenance costs or operational downtimes.

In contrast, the other options can contribute to system performance concerns but do not address the specific corrosive challenges presented by sulphur-laden condensate. For example, while heat exchangers indeed handle fluids at various pressures and can be exposed to different temperatures, it is the interaction with high sulphur condensate that necessitates the emphasis on corrosion resistance. Similarly, being located outdoors may expose heat exchangers to environmental factors but is not the primary reason for requiring corrosion resistance when it comes to handling corrosive fluids.