Modified Mathematical Model for Fines Migration in Oilfields

摘要

Permeability decline during corefloods with varying water composition, especially with low salinity water, has been widelyreported in the literature. It has often been explained by the lifting, migration and subsequent plugging of pores by fineparticles, which has been observed in numerous core flood tests with altered water composition. In the present paper, wederive a new system of governing equations describing fines mobilisation, migration and subsequent permeability decline for1-phase and 2-phase flows. In large scale approximation, the mathematical model for 2-phase flow with induced finesmigration is equivalent to polymer flooding model. It allows taking advantage of the polymer flooding option for the Eclipseblack oil simulator in order to model waterflood with low salinity water, where the induced fines migration and permeabilitydamage can be considered to provide a relatively simple method for mobility control during waterflooding. The modellingshowed that permeability decline in the water swept zone, caused by the alteration of the injected water composition andinduced fines migration, may be able to improve waterflood performance by delaying water breakthrough and reducing thewater cut.