Page 279 - Reservoir Formation Damage

Two-Phase Formation Damage by Fines Migration 259

Prediction of formation damage due to dynamic mud filtration in two-
phase flow was also carried out to demonstrate the capacity and appli-
cation of the model and to provide a comparison with single-phase flow
results. If the core studied by Jiao and Sharma (1992) was saturated by
oil prior to mud filtration, the invasion of the water-based mud would
lead to two-phase flow of oil and water in the rock. The same model
parameters determined above for mud filtration in single-phase flow were
used. Additional data necessary for simulation, including connate water
saturation, residual oil saturation and relative permeabilities, are adapted
from the case of fines migration in two-phase flow that was also simulated
above. The predicted mud filtration volume and permeability alteration
in two-phase flow are also plotted in Figures 11-9 and 11-10, as denoted
by the dashed lines. These results indicate that filtration volume and
formation damage are significantly less when a water-based mud invades
an oil-bearing formation. This is because the total mobility for simul-
taneous two-phase flow of water and oil is usually less than that of single
phase of water in formations, especially in Berea sandstones, which are
generally strongly water-wet and have a very low permeability for water
phase with the presence of oil in the formations.

References

Civan, F., "A Generalized Model for Formation Damage by Rock-Fluid
Interactions and Particulate Processes," SPE Paper 21183, Proceedings
of the SPE 1990 Latin American Petroleum Engineering Conference,
October 14-19, 1990, Rio de Janeiro, Brazil, 11 p.
Civan, F., Predictability of Formation Damage: An Assessment Study and
Generalized Models, Final Report, U.S. DOE Contract No. DE-AC22-
90-BC14658, April 1994.
Civan, F., "A Multi-Phase Mud Filtrate Invasion and Well Bore Filter
Cake Formation Model," SPE Paper No. 28709, Proceedings of the
SPE International Petroleum Conference & Exhibition of Mexico,
October 10-13, 1994, Veracruz, Mexico, pp. 399-412.
Civan, F., "A Multi-Purpose Formation Damage Model," SPE 31101
paper, Proceedings of the SPE Formation Damage Symposium, Lafayette,
Louisiana, February 14-15, 1996, pp. 311-326.
Civan, F., "Convenient Formulations for Immiscible Displacement in
Porous Media," SPE Paper 36701, Proceedings of the 71st SPE Annual
Tech. Conf. and Exhibition, Denver, Colorado, October 6-9, 1996,
pp. 223-236.
Collins, E. R., Flow of Fluids Through Porous Materials, Penn Well
Publishing Co., Tulsa, Oklahoma, 1961, 270 p.