Page 161 - Reservoir Formation Damage

Paniculate Processes in Porous Media 143

The external processes occur over the formation face and are discussed
in Chapter 12. The internal processes occur in the porous media and can
be classified in three groups as (Civan, 1990, 1994, 1996):

1. Pore Surface Processes
a. Deposition
b. Removal
2. Pore Throat Processes
a. Plugging (screening, bridging, sealing, Figure 8-2)
b. Unplugging
3. Pore Volume Processes
a. In-Situ Cake Formation
b. In-Situ Cake Depletion
c. Migration
d. Generation and Consumption (chemical reactions, rock defor-
mation and crushing, liberation of fine particles by chemical
dissolution of cement, coagulation/disintegration)
e. Interphase Transport or Exchange

(c)

Figure 8-2. Mechanism of pore throat blocking: a) plugging and sealing,
b) flow restriction, c) bridging (after Civan, 1994; reprinted by permission of
the U.S. Department of Energy).