Experience in Norsk Hydro with Cubic Equations of State
نویسنده
چکیده
The paper presents some specific applications of cubic equations of state (EOS) in Norak Hydro and points out some aspects of such equations that one should be aware of when using them or when developing new equations. Is is emphasized that the use of EOS to calculate vapor-liquid equilibrium is inherently empirical. Activity coefficients predicted’ for some systems by the Soave-Redlich-Kwong (SRK) equation of state are presented. The limitations of the van Laer equation for activity coefficients which may be derived from SRK at infinite pressures does not necessarily apply at finite pressures. The shortcomings of the SRK equations of state are pointed out and suggestions are given on how to develop an extended SRK-equation.
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