Page 258 - Reservoir Formation Damage

Chapter 11

Two-Phase Formation

Damage by Fines
Migration

Summary

Most reservoirs contain multi-phase fluid systems. Formation damage
processes in such reservoirs are more complicated because of the effects
of the relative wettabilities of fine particles and formation, interface
transport, relative permeabilities, and capillary pressures. There are only
a few models available for multi-phase systems. These models have been
developed for and tested with two phase laboratory core flow data. This
chapter discusses the additional processes on top of those involving
single-phase formation damage that need to be considered for multi-phase
formation damage by fines migration. A systematic analysis and formu-
lation of the relevant processes involving fines migration and formation
damage during two-phase fluid flow through sedimentary formations
is presented, as well as applications to typical laboratory core damage
tests. The formulation can be readily extended for the multi-phase and
multi-dimensional systems and the actual fluid conditions existing in
reservoir formations.

Introduction

Several investigators including Muecke (1979), Sarkar (1988), and
Sarkar and Sharma (1990) have determined that fine particles behave
differently in a multi-phase fluid environment and formation damage
follows a different course than the single-phase systems. However, the
reported studies on the two-phase formation damage are very limited.
Sutton and Roberts (1974) and Sarkar and Sharma (1990) have experi-
mentally observed that formation damage in two-phase is less severe than
in single-phase. Liu and Civan (1993, 1995, 1996) have shown that two-phase

238