Page 102 - PVT Property Correlations

80 PVT Property Correlations

TABLE 4.10 Heating Value Calculations for Sample 2
Component Mole % L cj y j 3 L cj z j y j 3 (1 2 z) 0.5

N 2 2.30 0.0 0.000 0.994 0.001736
CO 2 7.82 0.0 0.000 1.000 0.001354
C1 77.60 101.0 78.376 0.998 0.034704
C2 7.41 1769.6 131.127 0.992 0.006669
C3 2.08 2516.0 52.335 0.983 0.002752
i-C4 0.44 3251.9 14.308 0.971 0.000748
n-C4 0.48 3262.3 15.659 0.967 0.000876
i-C5 0.18 4000.9 7.202 0.948 0.000410
n-C5 0.17 4008.9 6.815 0.942 0.000409
C6 0.16 4755.9 7.609 0.910 0.000480
C7 1 1.36 5502.5 74.834 0.852 0.005232
1093.65 0.055371
z 5 0.9969
L c 5 1097

Volumetric Calculations of Fluids in Place for Wet Gas
Reservoirs
The main difference between dry gases and wet gases is the production of
reasonable (sometimes significant) condensate amounts in the latter.
Therefore, the original gas in place (OGIP) and prediction of reservoir per-
formance calculations for wet gas reservoirs differ from those for dry gas
reservoirs. In volumetric calculations, it is necessary to consider the volume
of liquid (vaporized in the gas phase under reservoir conditions) that will
condense at surface. The gas under reservoir conditions is found as gas with
vaporized condensate. When it is brought to the surface, both gas and con-
densate will be produced. The following section details the required calcula-
tions to estimate the expected amounts of both gas and condensate that will
be produced from the reservoir gas.
The fraction of OGIP that will be produced in the gaseous phase is given
by Eq. 4.13.

G 5 f g G T ð4:13Þ
The amount of condensate present in the reservoir gas (as vaporized liq-
uid) when it is brought to the surface is calculated from Eq. 4.14.