Self-cleaning effect in spiral heat exchangers:
Shell-and-tube heat exchangers gradually lose efficiency in applications with heavy fouling. The result is lower energy transfer and high maintenance costs.
Spiral heat exchangers on the other hand have a self-cleaning design, making them much less prone to these problems and very suitable for handling highly fouling fluids. Examples of where spiral heat exchangers are used include oil refineries, pulp and paper mills, mineral processing plants, and petrochemical plants, typically in services most suffering from fouling.
This example is based on input from a European oil refinery, where spiral heat exchangers replaced shell-and-tubes in a visbreaker cooler service (interchanger) in an existing plant. There are usually multiple heat exchangers operating in parallel in this service, but this example shows a one-to-one comparison between the two technologies.
The increased heat recovery in this case originates from two factors; reduced downtime and better performance due to less fouling build up. Reduced fouling also means reduced cleaning frequency and lower cleaning costs.
The two alternatives in this example represent two different maintenance philosophies; making few or many stops for cleaning.