Plate heat exchangers are the type of heat exchanger of choice whenever the temperature difference between the two fluid streams is low, in which case shell and tube heat exchangers are inefficient.
Plate heat exchangers achieve high efficiency due to the large exchange surface between the two fluid streams, but they easily suffer from fouling problems and relatively high pressure drop.
Types of Exchangers
Plate heat exchangers can be built as welded or demountable. Soldered ones are very economical, but cannot be disassembled for cleaning, which makes them unusable in applications where either fluid is not very clean. It should be noted that plate heat exchangers achieve high efficiency because the fluid streams flow through very narrow channels in which it is possible to achieve a large contact surface between the two fluids.
In industrial applications, it is most common to resort to dismountable models, which in large sizes already incorporate supports and other accessories that facilitate quick disassembly and allow cleaning operations to be carried out simply and in a short time.
Although plate heat exchangers are most commonly used for liquid-liquid exchanges, there are also models designed to use steam as the heating fluid.