Plate Heat Exchangers PHEs

Properties of liquid to be heated/cooled for example, density, specific heat, viscosity, thermal conductivity, pH, free acid/alkaU concentration, etc. Heating/cooling load in kcal/hour. 

Properties of the service liquid (e g., cooling water) available at site— TDS, pH, temperature, suspended solids, dissolved gasses if at r. 

Temperature at which cooling water will be available. 

If heat recovery is desired, then the temperature up to which it is desired to heat up the cooling water. 

MOC and method of fixing gaskets e.g. viton gaskets for Sulphtuic acid service. 

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TABLE 2 Micromixing Performance for Plate Heat Exchangers (PHE) and Offset Strip Fin (OSF) Heat Exchangers... 

The plate-and-frame or gasketed plate heat exchanger (PHE) consists of a number of thin rectangular corrugated or embossed metal plates sealed around the edges by gaskets and held... 

The heat of absorption being removed by Plate Heat Exchanger (PHEs) for anod-ically passivated sulfuric acid coolers... 

Plate heat exchangers (PHEs) are the most common form of compact heat exchanger, but their area densities are inferior to other types discussed in this chapter. There are several forms of construction, mainly associated with the methods used to seal the edges of the plates - gaskets, braze, welding or laser welding. The PHE is widely used in the liquid food processing industry, where the use of... 

Typical plate heat exchanger dimensions and performance parameters are given in Table 17.2 [1], Any metal that can be cold-worked is suitable for PHE applications. The most com-... 

Modem cooling systems use plate heat exchangers which need a much smaller area than the above (only about one quarter). It is possible to get hot water of up to 65-70 °C from the PHE and thus recover heat from the hot acid. This hot water can be used for process work or for heating offices during winter, etc. 

Liquid-to-Liquid Exchangers. Liquid-to-liquid and phase-change exchangers are plate-and-frame and welded PHE, spiral plate, and printed circuit exchangers. Some of these are described in some detail later in this section. Some compact heat exchangers and their applications are now summarized. 

Note that the PCHE is too expensive for such an application in current circumstances, but PHEs can replace shell and tube units to give a reasonable volume reduction. Much can also be done with plate-fin heat exchangers - see Chapter 4. 

Figure 10-157. Convection heat transfer comparison for shell and tube and plate and frame exchangers. (Used by permission Bui. PHE 96-1 6/96. Graham Manufacturing Company, Inc.)...

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