Plate heat exchangers have been used for heating process streams with steam or hot water and for cooling product streams with tower, city or seawater. However, most installations are for heat recovery - with good reason.
The plate heat exchanger provides an excellent means of achieving high efficiency in heat recovery. Full countercurrent flows, as well as its ability to produce high heat transfer coefficients, enable it to produce a close end temperature difference. For example, some plate heat exchangers can achieve 97 percent heat recovery even at temperatures approaches as low at 2°F. This is highly important to plants with sources of low grade or poor quality heat.