Page 104 - PVT Property Correlations

82 PVT Property Correlations

TABLE 4.12 Results of Volumetric Calculations for the Two Example Fluids
Parameter Unit Reservoir 1 Reservoir 2
Total OGIP from gas composition scf 1.41427E 1 11 1.42396E 1 11
Total OGIP from CGR scf 1.40431E 1 11 1.40322E 1 11
Total OGIP from separator scf 1.46089E 1 11 1.40322E 1 11
conditions
Fraction of total OGIP produced as Fraction 0.958432621 0.98990883
gas (f g )
OOIP from gas composition STB 9462,335 2213,026
OOIP from CGR STB 9395,699 2180,797
OOIP from separator conditions STB 9774,280 2180,797

CGR, condensate gas ratio. OGIP, original gas in place. OOIP, original oil in place.

R t 14; 325
f g 5 5 5 0:958
ð
R t 1 132; 800γ =M o 14; 325 1 132; 800Þð0:81Þ=173:14
o
11
f g G T ð 0:958Þð1:4 3 10 Þ 6
N 5 5 5 9:36 3 10 STB
R t 14; 325
The calculations of total gas in place and oil in place for both reservoirs
and with the different assumptions for reservoir gas specific gravities are
summarized in Table 4.12.

Economic Considerations for Wet Gas Reservoirs

In dry gas reservoirs, condensate production may not be very important from
an economic point of view. However, for many wet gas reservoirs, conden-
sate production constitutes an important revenue stream in the project.
Failure to quantify the economic impact of the expected condensate produc-
tion may lead to overlooking some potentially promising wet gas develop-
ment projects. The condensate production from some wet gas reservoirs
(which are close to being considered gas condensate) may be as high as half
the value of the entire project.
For the above two reservoirs, and assuming recovery factor for both res-
ervoir of 85%, gas price of $3/Mscf, and condensate price of $50/STB, the
results are given in Table 4.13.
The average OGIP and OOIP are used in the calculations shown above.
In the first reservoir, the condensate value is even higher than the value of
the gas. The richness of the wet gas plays a significant role in development