Page 55 - PVT Property Correlations

Dry Gases Chapter | 3 35

TABLE 3.2 Problem 1 Calculations
Component Mole % Mole Fraction Molecular Weight Y i 3 M i

N 2 2.92 0.0292 28.013 0.818
CO 2 1.07 0.0107 44.010 0.471
H 2 S 0.00 0.0000 34.080 0.000
C1 87.63 0.8763 16.043 14.058
C2 4.77 0.0477 30.070 1.434
C3 1.85 0.0185 44.097 0.816
i-C4 0.49 0.0049 58.123 0.285
n-C4 0.58 0.0058 58.123 0.337
i-C5 0.20 0.0020 72.150 0.144
n-C5 0.20 0.0020 72.150 0.144
C6 0.29 0.0029 86.177 0.250
Total 100 1 18.76

1 pM 6:93
ρ 5 5 5 0:048psi=ft
144 zRT 144
Apparent molecular weight of the gas:
nc
X
M g 5 y i 3 M i 5 18:76
i51
Specific gravity of the gas:
M g 18:76
γ 5 5 5 0:6469
g
29 29

Gas Viscosity
Viscosity is defined as the resistance to flow exerted by a fluid. The viscosity
is usually measured in centipoise (cp 5 g/100 s cm). The centipoise is a unit
for measuring dynamic viscosity. Dynamic viscosity is of particular interest
to reservoir and production engineers as it is a reflection of resistance of the
fluid to flow. Kinematic viscosity, or static viscosity, is calculated by divid-
ing the dynamic viscosity by density. Kinematic viscosity is measured in
3
centistokes [centistokes 5 cp/(g/cm )].