Page 135 - Principles of Applied Reservoir Simulation 2E

Chapter 13

Fluid Properties

Properties of petroleum fluids must be quantified in a reservoir simulator.
The range of applicability of a reservoir simulator is defined, in part, by the
types of fluids that can be modeled using the mathematical algorithms coded
in the simulator. For these reasons, it is worth considering the general types of
fluids that may be encountered in a commercial reservoir environment [for
example, see Pedersen, et al., 1989; Koederitz, et al., 1989; McCain, 1973; and
Amyx, etal., I960].

13.1 Fluid Types

An estimate of the elemental composition (by mass) of petroleum is
given in the following chart:
Carbon 84% - 87%

Hydrogen 11%- 14%
Sulphur 0.6% - 8%
Nitrogen 0.02% - 1.7%

Oxygen 0.08% - 1.8%
Metals 0% - 0.14%
It can be seen from the table that petroleum fluids are predominantly hydro-
carbons. The most common hydrocarbon molecules are paraffins, napthenes,
and aromatics because of the relative stability of the molecules. A paraffin is

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