Associative Polymers for EOR - Towards a Better Understanding and Control of Their Adsorption in Porous Media

Adsorption properties of associative polymers (AP) were investigated in porous media to evaluate the performances of these chemicals as EOR mobility control agents. Two different AP were studied. For AP Type 1, results indicated a strong adsorption as compared to equivalent non associative polymers and a poor in-depth propagation. AP Type 2 were easily injected, and their adsorption was found to depend on the ionic strength of the dilution brine. It is thus shown that: i) AP adsorption is a significant parameter for the success of polymer flooding operations since it can impair injectivity and reduce the effective viscosity of the polymer solution, and ii) a control of AP adsorption can be achieved through an adjustment of the injection conditions.