Page 146 - Reservoir Formation Damage

Chapter 7

Multi-Phase and

Multi-Species
Transport in

Porous Media*

Summary
The fundamental concepts, definitions, expression of species content,
and conservation laws in multi-phase and species environments in porous
media are presented in this chapter by expanding the overview and
developments given by Civan (1993, 1996).

Multi-Phase and Species Systems in Porous Media

The reservoir formation is considered in three parts: (1) the stationary
or deforming solid phase containing (a) porous matrix made from detrital
grains, minerals and clays, and (b) the immobile materials attached to the
pore surface including authigenic or diagenetic minerals and clays; various
deposits; scale forming precipitates such as wax, asphaltene, sulfur, and
gels; trapped gas, connate water and residual oil; (2) the flowing or
mobile fluid phases including (a) gas, (b) oil, (c) brine, and (d) chemicals
used for improved recovery; (3) various types of species that the solid
and fluid phases may contain.
Typical species are (1) ions including the anions such as Cl~, HCOj,
+2
+
+2
2
+2
+
CO; , SC>4 2 and the cations such as K , NA , Ca , Ba , Mg ; (2) mole-
cules such as CH 4 ,CO 2 ,H 2 S, N 2 , molasses, polymers, surfactants, paraffin,
asphaltene, and resins; (3) pseudocomponents such as gas, oil, and brine
with prescribed compositions; (4) particulates such as minerals, clays,
* After Civan, ©1996 SPE; parts reprinted by permission of the Society of Petroleum
Engineers from SPE 31101 paper.

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