Category: Heat Exchangers

Heaters Operating temperatures can be classified into three ranges: low (< 120C), medium (120-250C), and high (>250C). low temperature-range heaters generally tend to use condensate or steam, medium temperature-range heater tend to steam, and high temperature-range heaters tend to use fired heaters or hot oil loops (<400C) Temperature and required heat load are important factors…

Condensing heat transfer is important because many heat transfer applications will condense the steam used as the hot stream, and often gaseous products are needed in liquid form. There are two types of condenser: total condensers and partial condensers. Both total and partial condensers need to account for the accumulation of noncondensable vapor. This can…

Boiling Heat Transfer Coefficient Boiling liquids have different heat transfer regimes. I: Heat transfer with natural convection II: Heat transfer with bubbling agitation III: Heat transfer with nucleate boiling with unstable film IV: Heat transfer with stable film boiling V: Radiant Heat Transfer The heat transfer coefficient of a boiling liquid begins to decrease with…

Heat transfer involving boiling liquids or condensing vapor is different from heat transfer involving constant fluid phases. Heat transfer operations that involve phase changes are typically carried out in separate units in order to account for the different physical properties of the phases.

Double Pipe The double-pipe heat exchanger is one of the simplest heat exchangers utilized in industry. This exchanger’s name comes from how one fluid flows inside a pipe and the other fluid flows between that pipe and another pipe that surrounds the first, essentially a “tube within a tube.” One way to improve heat transfer…

The heat exchanger must meet certain physical requirements both to carry out the specified heat exchange and operate properly as part of a system. As such, it must provide the correct area for the specified heat exchange while maintaining a reasonable pressure drop, contain the pressure of the streams, prevent leaks between the tubes and…

Process equipment and streams will need to be heated or cooled. One way to reduce consumption of utilities is to exchange heat between these streams. For example, if a product stream requires cooling, the excess heat can be used to preheat a feed stream that requires heating by using an appropriate heat exchanger. Here the…

There are three mechanisms of heat transfer: conduction, convection, and radiation. In most heat exchangers, convection will be the dominant mechanism. Conduction and radiation will generally be negligible in large heat exchangers, but radiation will be important in fired heaters. Heat transfer across a surface by convection is given by the equation: �=���Δ�� Where: � = heat transferred…