Page 44 - Standard Handbook Petroleum Natural Gas Engineering VOLUME2

64 Reservoir Engineering

The dead oil viscosity can then be adjusted for dissolved gas with the correlation
by Chew and Connally [6] (Figure 5-10) for saturated oil:

where A and b are functions of solution gas-oil ratio.
Fit of A and b values given in Table 3 of Reference 6 are

A = antil0g{R,[2.2(10-~)R, -7.4(104)]}

0.68 0.25 0.062
b= + +
)
ioa6*( 10" ) R, 101.1 (1 o-~ R, ( 10" R,
The equation for compressibility factors of natural gases (Figure 5-13) is:

Z = A + (1 - A)/eB + C pD,, (5-22)

where A = 1.39(Tpr - 0.92)0.5 - 0.36Tpr - 0.101
0.066 1 0 32 6
B = (0.62 - 0.23Tpr)pp, + -0.037 pir +-
(Tpr -0.86) log(~;:) Ppr
C = (0.132 - 0.32 log Tpr)
D = antilog (0.3106 - 0.49Tpr + 0.1824Tir)
T, is the dimensionless pseudo-reduced temperature, and p, is the dimensionless
pseudo-reduced pressure. The relationship between formation volume factor of
bubble-point liquids and gas-oil ratio, dissolved gas gravity, API oil gravity, and
temperature (Figure 5-3) is [30]:

Bo, = 0.9759 + 12 (10-5)(CN)Bob 1.2 (5-23)

0.5
where (CN)Bob = Rs(2) +1.25T

where (CN)Bo, = bubble-point formation volume factor correlating number
R, = solution gas-oil ratio in ft3/bbl
y, = gas gravity (air = 1)
yo = oil specific gravity (water = 1)
T = temperature in OF
The correlation of bubble-point pressure with dissolved gas-oil ratio, dissolved
gas gravity, API oil gravity, and temperature (Figure 5-2) is [30]:
P, = 18.2[(CN)pb - 1.41 (5-24)