3. Refrigeration processes in chemical engineering and gas liquefaction

3.1 The role of refrigeration

Refrigeration plays a vital role in chemical engineering, since lowering the temperature, especially below ambient temperature, can enable condensation of liquid phases, solidification of fluids, crystallization of products in solution, and control of chemical reactions...

On the other hand, a large number of processes require the use of low temperatures when the production and liquefaction of purified gases involve fluids whose critical temperature is well below ambient temperature, as is the case for air gases and certain light hydrocarbons (generally with molecules containing no more than three carbon atoms).

Unlike other industrial applications, it is necessary to distinguish between two ways of using...