Applications Joule-Thomson effect

The origin of the nonvauishing Joule-Thomson effect is the effective repulsive (Fermions) and attractive (Bosons) potential exerted on the gas molecules, which arises from the different ways in which quantum states can be occupied in sy.stems obeying Fermi-Dirac and Boso-Einstein statistics, respectively [17]. In other words, the effective fields are a consequence of whether Pauli s antisymmetry principle, which is relativistic in nature [207], is applicable. Thus, a weakly degenerate Fermi gas will always heat up ((5 < 0), whereas a weakly degenerate Bose gas will cool down (5 > 0) during a Joule-Thomson expansion. These conclusions remain valid even if the ideal quantum gas is treated relativistically, which is required to understand... 

The expansion phenomena (generation of low temperature by expansion) of compressible media is well described by the Joule-Thomson effect, which may be used as basic information on the applicability of a certain gas in the PGSS-process. If heat-transfer, changes in kinetic energy, and work-transfer for the flow process through an expansion valve are neglected, then the process may be considered to be isenthalpic [33]. The effect of change in temperature... 

The enthalpy H of an ideal gas depends only on temperature and not on pressure because of the absence of intramolecular forces. In a real gas these forces cannot be neglected, and H depends on pressure. In most cases this leads to a decrease in temperature if a real gas is adiabatically expanded (Joule-Thomson effect, named after James Prescott Joule and William Thomson, see boxes). This property is relevant for many practical applications, for example, for refrigerators, heat pumps, and for the coohng and liquefaction of gases (Linde process). 

It has been demonstrated that the Joule-Thomson effect could lead to undesired consequences in CCS operations if not handled appropriately. Hydrate or dry ice may form under certain operating conditions and thus need to be taken care with extreme caution. Appropriate prevention guidelines have been developed and should be incorporated into applicable operating procedures. 

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