Permeability Damage Induced by Low and High Molecular Weight Polymer Gels in Porous Media

Nurbol Tileuberdi1,Email

Bauyrzhan Nassibullin2

Ardak Yskak2

Iskander Gussenov3

1Institute of Geological sciences named after K.I.Satpaev, Satbayev University, Almaty 050013, Kazakhstan. 
2Department of Petroleum Engineering, Satbayev University, Satbayev St. 22a, Almaty 050013, Kazakhstan.
3Laboratory of Engineering Profile, Satbayev University, Satbayev St. 22a, Almaty 050013, Kazakhstan.

Abstract

The current challenge in oil fields is high water cuts and low oil production due to high permeability layers causing water breakthrough. Polymer gels are commonly used to treat wells and reduce water permeability. However, polymers infiltrating oil-saturated zones may reduce oil permeability. Thus, a comprehensive study on polymer behaviour in porous media is imperative. 0.3% low molecular weight gelant caused inlet plugging in 0.258 mD core, while 0.5% in 3.4 mD core did not. Acceptable permeability reduction to hydrocarbon fluid was observed only when the medium-high permeability short core was treated with low molecular weight gelant. However, the reduction of resistance and residual resistance factors along the length of the cores indicates polymer retention, suggesting the need for experimenting with longer cores. Residual resistance factors to 3.15 cp oil provided by the low and high molecular weight gels were not significantly different and equalled to 70-79. Polymer gels can cause severe oil production loss in a radial flow pattern. Additionally, the relatively low difference between residual resistance factors for water and oil disqualifies the tested gels for the treatment of linear flow problems in production wells. The tested gels may find a better application for the treatment of injection wells.

Permeability Damage Induced by Low and High Molecular Weight Polymer Gels in Porous Media