Scientific and technical journal

«Proceedings of Gubkin University»

ISSN 2073-9028

Proceedings of Gubkin University

UDC: 66.011
DOI: -


Fedorova Elena B.1,
Mel'nikov Vyacheslav B.1

1 Gubkin Russian State University of Oil and Gas (National Research University)

Keywords: liquefied natural gas, LNG, phase equilibrium


Thermodynamic research on phase equilibrium of natural gas components mixtures plays an important role in the technological processes design for LNG plant. As liquid-vapor equilibrium issues of natural gas systems have been studied well, at present research is concentrated on multiphase systems, containing mixtures of hydrocarbons with inorganic substances, such as water, carbon dioxide, hydrogen sulfide, nitrogen, hydrogen. Issues of phase equilibrium of binary, ternary and 4-component mixtures containing methane, ethane, propane and nitrogen are considered. It is outlined that nitrogen-hydrocarbon mixtures could display properties of both mutually soluble substances and partially soluble ones, depending on thermodynamic conditions and components content ratio. Areas of existence of three-phase systems “liquid-liquid-vapor” were calculated. The results obtained are of great importance in LNG processes design and modernization, as well as in the development of processes of nitrogen extraction from natural gas.


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