The effects of wettability on gel performance in layered heterogeneous reservoirs

Abstract

Regarding the application of enhanced oil recovery (EOR), reservoir heterogeneity leads to early water breakthrough and significant water production, so that substantial costmay be needed to treat theproduced water. Gel treatmentshavebeen widely used to prevent early water breakthrough and great amount of water production by the modification of permeability. Reservoir wettability gives significant impact on gel treatment. This study is to assess the effect of wettabilityon the reservoir performance duringgel treatment in layered heterogeneous reservoirs. Performances were compared in terms of water-oil ratio and cumulative oil recovery for different wettability conditions.With respect to oil recovery, there is no striking improvement by gel treatment. However, the results indicate that gel process presents 77% decrement of water-oil ratio over waterfloodfor oil-wet system and 51% for water-wet system.Gel is distributed in reservoir more widely for oil-wet conditions than water-wet conditions, which means the effect of gels is more dominant in oil-wet conditions rather than water-wet conditions.