The Kinetics of Polymer Adsorption in Transport Through Porous Media: Basic Theory

A polymer transport and kinetic adsorption model is developed and applied to assist in the understanding of some recent results in polymer flow through porous media. The coupled equations in dimensionless form show that the system is governed by 3 dimensionless numbers, 2 of which are important: the Adsorption number (N_Ad) and the adsorption Damköhler number (N_Da-A). This leads to a wide range of behaviours in terms of the polymer effluent profiles, which are in broad qualitative agreement with experimental observations. The hypothesis is that it is the kinetics of the system (principally N_Da-A) that is strongly controlling the experimental observations. The model also predicts that the way to establish if this is true is to conduct a polymer core flood including "shut-in" stages where flow is stopped, then resumed after some period of time, depending on the kinetic adsorption timescale. Preliminary experiments support this, and a following paper will present these experimental results directly simulated using our model.