Thermodynamics Process Control in Fluid-phase Equilibria

Thermodynamics Process Control in Fluid-phase Equilibria 

Depth of the energy well of SW and Kihara s potential, and relative translational energy in the center line direction 

Infinite temperature Average Hard sphere Square well Repulsion Reduced property 

The accurate prediction of thermodynamic properties of natural gas systems is of interest for gas industry. Compressibility factors are used in energy and flow metering. It is also used in calculations of gas pressure gradient in tubing and pipelines. When large volumes of gas are traded between produeers, distributors, and consumers, error in the estimation of the amount of involved are of real economic significance. In gas condensate reservoirs, well-productivity often declines rapidly when pressure drops below the dew point pressure near-wellbore. Therefore, it is very important to accurately determine the dew point pressure. The pressure and temperature of most natural gas mixtures can be found up to 150 MPa and 500 K, respectively (Nasrifar and Boland, 2006). At these eonditions, methane, ethane, and nitrogen are almost always supercritical while other hydroearbons are subcritical. Thus, the equation of state of natural gas mixture must be aeeurate at supercritical and subcritical behavior of methane and heavy hydrocarbons, respectively. 

Cubic equations of state are eommonly used in the gas industry to predict phase behavior and volumetric properties of hydroearbon reservoir fluids. In general, these 

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Molecular Thermodynamics Process Control in Fluid-phase Equilibria... 

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