MODEL DEVELOPMENT OF A SUITABLE EQUATION OF STATE FOR MULTICOMPONENT MULTIPHASE SYSTEMS: APPLICATION TO CRUDE OIL PHASE STABILITY REQUIREMENTS

Year 2018, , 111 - 118, 30.05.2018

Faith Babalola , Alfred Susu

https://doi.org/10.5541/ijot.419923

Cited By: 3

Abstract

A suitable Equation of State (EOS) was developed
for multi component, multi phase systems from the Peng-Robinson Equation of
State using a newly developed variable parameter ‘a’ approach (VPAA) which
treats the attractive term parameter as a variable regressed by two straight
lines. This EOS was used to determine the stability limit curves for crude oils
from three different oil wells on the application of the Helmholtz free energy
criterion for intrinsic stability. This was used along with the T-isotherm for
the crude oils and the stability limit was found by locating the point of
intersection of the two curves. For Well-1, the vapor phase was unstable while
the liquid phase was stable at 47.4 atm. For Well-2, the vapor phase was stable
at 209 atm. while the liquid phase was stable at two pressure values of 191atm.
and 213 atm. For Well-3 however, the vapor phase was stable at 45.7 atm. while
two liquid phases were identified. The lighter one was unstable at the
temperature of interest, while the heavier one was stable at 115.9 atm.

Keywords

Equation of state, phase stability, reservoir fluids, model, EOS parameter

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