Heat exchanger classification
1. Classification by heat transfer principle
Surface heat exchanger: two kinds of fluids with different temperatures flow in a space separated by a wall surface, heat conduction through the wall surface and convection of the fluid on the wall surface, and heat exchange between the two fluids. Surface heat exchangers are available in shell, sleeve and other types of heat exchangers.
Regenerative heat exchanger: a heat storage body composed of solid matter transfers heat from a high temperature fluid to a low temperature fluid. After the heat medium reaches a certain temperature by heating the solid matter, the cold medium is heated by the solid matter to make it reach The purpose of heat transfer. The regenerative heat exchanger has a rotary type, a valve switching type, and the like.
Fluid-connected indirect heat exchanger: a heat exchanger that connects two surface heat exchangers by a heat carrier circulating therein. The heat carrier circulates between the high-temperature fluid heat exchanger and the low-temperature fluid, and is accepted at a high temperature fluid. Heat, in a cryogenic fluid heat exchanger, releases heat to the cryogenic fluid.
Direct contact heat exchanger: It is a device that directly contacts two fluids for heat exchange, for example, a cold water tower, a gas condenser, and the like.
2. Classified by purpose
Heater: The fluid is heated to the necessary temperature, but the heating fluid does not change in phase.
Preheater: Preheats the fluid to provide standard process parameters for process operation.
Superheater: Used to heat fluid (process gas or steam) to a superheated state.
Evaporator: used to heat the fluid to a temperature above the boiling point to evaporate the fluid, generally with a change in phase.
3. Classified by structure
Can be divided into floating head heat exchangers, fixed tube plate heat exchangers, U-shaped tube plate heat exchangers, plate heat exchangers and so on.