Page 66 - PVT Property Correlations

44 PVT Property Correlations

FIGURE 3.7 Sequence of calculations for computing dry gas PVT properties.

APPLICATIONS OF TECHNIQUES TO COMPUTE PVT
PROPERTIES FOR DRY GASES

Many gas reservoirs worldwide can be treated as dry gas for engineering pur-
poses. These reservoirs do not drop appreciable amounts of condensate when
the gas is produced at surface. Engineering these reservoirs requires the cal-
culation of their PVT properties. The following solved examples illustrate
use of the correlations to arrive at estimates of gas PVT properties.

Problem 2—Estimation of Critical Properties

For the gas composition given in Table 3.11, calculate critical pressure and
temperature from both gas-specific gravity and gas composition by the fol-
lowing methods:
Sutton (2007) using the gas-specific gravity.
Kay’s rules (Kay, 1936) and Elsharkawy (2000) using the gas
composition.