Page 193 - Formation Damage during Improved Oil Recovery Fundamentals and Applications

Formation Damage by Fines Migration: Mathematical and Laboratory Modeling, Field Cases 167

2.2

1.8
High sal water
J Low sal water, β=200
1.4 Low sal water, β=100

1

0.6

0 0.4 0.8 1.2 1.6 2
T,PVI
Figure 3.29 Impedance plotted against the number of PVI for high-salinity water
injection, and two cases of low-salinity water injection with different formation dam-
age coefficients (J: impedance, PVI: number of pore volumes injected).

Table 3.15 Impedance calculation during low-salinity and high-salinity water
injection applying inverse mapping
Case s I k rwor s or k rwoi n w n o β
High-salinity water 0.2 0.5 0.3 1 3 4 0
Low-salinity water 0.2 0.5 0.3 1 3 4 100, 200

3.8 CONCLUSIONS
The mathematical formulations and exact solutions presented here
provide a means for petroleum engineers to quantify and predict forma-
tion damage due to fines migration. The main two causes of fines migra-
tion are high fluid velocities and low fluid salinities. Equations for both of
these cases, as well as descriptions of the mechanisms for damage, have
been presented in the prceeding sections. Finally, a brief extension of
these works into the two-phase environment has been presented alongside
a methodology for predicting injectivity decline.
All formulations presented here are still reliant on several limitations
and assumptions. Of the most relevance to application in the petroleum