Materials in heat exchangers

Materials in heat exchangers

Heat exchangers are built of different materials for different purposes. It is important that the material has good conductivity, such as a metal, and that the heat transfer surfaces are corrosion-resistant. In fish farming, it is also important that the materials do not release substances that are toxic for the fish, e.g. copper. The more contami-nated the flowing media are, either by acids or bases, the more resistant to corrosion the heat transfer surface areas need to be; however, this will increase the price of the material.

If the media are water and it is uncontaminated, stainless steel could be used. If the water is conta-minated to some extent, for instance with humus substances, acid-proof steel at least should be used. If the water is salt or brackish, titanium covered plates ought to be used. For ground water titan-covered plates are also recommended; the price of these is, however, much higher than for stainless steel plates.