Product Details
I. Definition
Heat exchangers, also known as heat exchange units, are devices that transfer a portion of heat from a hot fluid to a cold fluid. They play a crucial role in various industrial processes, including chemical, oil, power, food, and many others. In chemical production, heat exchangers can serve as heaters, coolers, condensers, evaporators, and reboilers, with wide applications.
II. Classified by Heat Transfer Principle
1. Shell and Tube Heat Exchangers Shell and tube heat exchangers are designed to transfer heat between two fluids of different temperatures, flowing in separated spaces by the wall. Heat is transferred through the wall's conduction and convection of the fluids at the wall surface.
2. Regenerative Heat Exchangers - These utilize a solid material-made storage body to transfer heat from a high-temperature fluid to a low-temperature fluid. The heat medium first heats the solid material to a certain temperature, and then the cold medium passes through the solid material to be heated, achieving the goal of heat transfer.
3. Indirect Fluid-to-Fluid Heat Exchangers: These are heat exchangers that connect two surface-type heat exchangers through a circulating heat transfer medium. The medium circulates between the high-temperature fluid heat exchanger and the low-temperature fluid, absorbing heat from the high-temperature fluid and releasing it to the low-temperature fluid in the heat exchanger.
4. Direct-contact heat exchangers, also known as mixed-flow heat exchangers, are devices where two fluids come into direct contact and mix for heat exchange. Examples include cooling towers and gas condensers.
5. A double-effect heat exchanger that combines both surface-to-surface indirect heat exchange between steam and water, and direct water-to-water mixing heat exchange. Compared to the surface-to-surface indirect heat exchange with steam and water, it offers higher heat exchange efficiency; compared to direct steam-water mixing heat exchange, it has greater stability and lower equipment noise.
III. Categorized by Usage
1. Heater - A heater is used to heat fluids to the necessary temperature without causing a phase change in the heated fluid.
2. The preheater preheats the fluid, providing standardized process parameters for the operation.
3. Superheater - Used to superheat fluids (process gas or steam) to a superheated state.
4. Evaporator - Used to heat fluids to temperatures above their boiling point, causing the fluid to evaporate, usually involving a phase change.
IV. Categorized by Structure
Available in: Floating Head Heat Exchangers, Fixed Tube Sheet Heat Exchangers, U-Tube Sheet Heat Exchangers, Plate Heat Exchangers, etc.
