Page 22 - Reservoir Formation Damage

6 Reservoir Formation Damage

2. Rock-fluid incompatibilities, for example contact of potentially
swelling smectite clay or deflocculatable kaolinite clay by non-
equilibrium water based fluids with the potential to severely re-
duce near wellbore permeability.
3. Solids invasion, for example the invasion of weighting agents or
drilled solids.
4. Phase trapping/blocking, for example the invasion and entrapment
of water based fluids in the near wellbore region of a gas well.
5. Chemical adsorption/wettability alteration, for example emulsifier
adsorption changing the wettability and fluid flow characteristics
of a formation.
6. Fines migration, for example the internal movement of fine par-
ticulates within a rock's pore structure resulting in the bridging
and plugging of pore throats.
7. Biological activity, for example the introduction of bacterial agents
into the formation during drilling and the subsequent generation
of polysacharide polymer slimes which reduce permeability.

Team for Understanding and Mitigation
of Formation Damage
Amaefule et al. (1987, 1988) stated that formation damage studies re-
quire a cooperative effort between various professionals. These and their
responsibilities are described in the following: (1) Geologist and geochem-
ist on mineralogy and diagenesis and reservoir formation characterization
and evaluation; (2) Chemist on inorganic/organic chemistry, physical
chemistry, colloidal and interfacial sciences, and chemical kinetics; and
(3) Chemical and petroleum engineers on transport phenomena in porous
media, simulator development, interpretation of laboratory core tests,
scaling from laboratory to field, interpretation of field tests, and devel-
opment and implementation of strategies for formation damage control.

Objectives of the Book

The focus of this book is to provide sufficient knowledge for the fol-
lowing purposes: (1) Understand relevant processes by laboratory and
field testing; (2) Develop theories and mathematical expressions for
description of the fundamental mechanisms and processes, and phenom-
enological mathematical modeling and obtain numerical solutions for
simulator development and computer implementation; (3) Predict and
simulate the consequences and scenarios of the various types of forma-
tion damage processes encountered in petroleum reservoirs; (4) Optimize
for prevention and/or reduction of the damage potential of the reservoir