Description of the basic classification of heat exchangers

Speaking of Heat Exchangers, this is an equipment facility suitable for realizing heat exchange. It is an indispensable and extremely important unit equipment in the process of production process. It is widely used in light industry, petrochemical industry, production and other industries. The heat exchanger has a heat transfer process in the operation project, the so-called heat transfer process. Thermal process refers to the analysis of various factors that affect heat transfer, and some technical measures are taken to increase the heat transfer area per unit volume of the heat exchanger, so that the equipment tends to be efficient and compact, save metal consumption and reduce power consumption.

In the application of heat exchangers, it is suitable for heat exchangers with different media, different working conditions, different temperatures and different pressures, and the structure types are also different. The specific classification of heat exchangers is as follows:

Classification by heat transfer principle

1. Partition-wall heat exchanger The partition-wall heat exchanger is that two fluids with different temperatures flow in the space separated by the wall surface, through the heat conduction of the wall surface and the convection of the fluid on the wall surface, and heat exchange between the two fluids. Dividing wall heat exchangers include shell and tube, casing and other types of heat exchangers. The partition heat exchanger is the most widely used heat exchanger at present.

2. Regenerative heat exchanger The regenerative heat exchanger transfers heat from a high temperature fluid to a low temperature fluid through a regenerator composed of solid materials. The heat medium first reaches a certain temperature by heating the solid material, and then the cold medium passes through the solid material. The substance is heated so that it achieves the purpose of heat transfer. Regenerative heat exchangers include rotary, valve switching, etc.

3. The fluid connection indirect heat exchanger is a heat exchanger that connects two surface heat exchangers by a heat carrier circulating in them. The heat carrier is in the high temperature fluid heat exchanger and the low temperature fluid heat exchanger. The fluids circulate between them, receiving heat in the high-temperature fluid, and releasing heat to the low-temperature fluid in the low-temperature fluid heat exchanger.

4. The direct contact heat exchanger is also called a hybrid heat exchanger. This heat exchanger is a device in which two fluids are in direct contact and mixed with each other for heat exchange, such as a cold water tower, a gas Condenser, and the like.

5. The compound heat exchanger has both steam-water surface indirect heat exchange and water-water direct mixed flow heat exchange equipment. Compared with steam-water surface indirect heat exchange, it has higher heat exchange efficiency; compared with steam-water direct mixing heat exchange, it has higher stability and lower unit noise.

Classification by use

1. Heater The heater is to heat the fluid to the necessary temperature, but the heating fluid does not change the phase.

2. Preheater The preheater preheats the fluid to provide standard process parameters for the process operation.

3. Superheater The superheater is used to heat the fluid (process gas or steam) to a superheated state.

4. Evaporator The evaporator is used to heat the fluid to a temperature above the boiling point, so that the fluid evaporates, generally with a phase change.

Also, if it is classified by structure, there are floating head heat exchangers, fixed tube sheet heat exchangers, U-shaped tube sheet heat exchangers, plate heat exchangers, and the like.