Polymer retention in porous

Willhite, G.P. Dominguez, J.G. Mechanisms of Polymer Retention in Porous Media in Improved Oil Recovery by Surfactant and Polymer Flooding, Shah, D.O. Schechter, R.S. (Eds.), Academic Press New York, 1977, pp. 511-554. 

This section discusses polymer rheology, polymer retention in porous media, and rock permeability reduction. 

Szabo, M.T., 1975. Some aspects of polymer retention in porous media using a C-tagged hydrolyzed polyacrylamide. SPEJ (August), 323-337. 

SZABO, M.T. "Some Aspects of Polymer Retention in Porous Media Using a C -Tagged Hydrolyzed Polyacrylamide", SPEJ, 15, 1975, 323... 

In connection with the experimental findings the question should be raised of mechanical entrapment which can also contribute to polymer retention in porous media if high polymer concentration is used. In our experiment the polymer concentration was 0.5 gdm and that corresponds to an oversaturated state in case of partially... 

SOME ASPECTS OF POLYMER RETENTION IN POROUS MEDIA USING A C14 TAGGED POLYACRYLAMIDE... 

The term dynamic retention will be used throughout the paper to refer to the polymer retention in porous media during polymer solution flow. 

Cohen and Christ (unpublished) presented a new experimental technique for determining mobility reduction resulting from polymer retentions in porous media. Their method was designed to separate the contributions of adsorption and non-adsorptive retention to be measured in their flow experiments using HPAM. This was done by using a silane treatment of the silica in their sandpacks, which changed the surface such that it no longer adsorbs HPAM. 

Polymer adsorption at a liquid/solid interface is a very well-established phenomenon and has an enormous associated literature (Lipatov and Sergeeva, 1974 Parfitt and Rochester, 1983). On the evidence from porous medium flow experiments it appears that mechanical entrapment is also a reasonably well-established mechanism for polymer retention in flow through porous media. Hydrodynamic retention is a rate-dependent effect which is rather less well understood. However, this retention mechanism is not a very large contributor to the overall levels of polymer retention in porous media and, although interesting, is probably not a very important effect in field-scale polymer floods. The important point to note is that it must be understood sufficiently well in laboratory floods so that core flood results can be interpreted correctly concerning polymer adsorption and entrapment retention mechanisms. 

This section revisits adsorption as the main fundamental mechanism of polymer retention in porous media in most practical situations. That is, it is assumed that mechanical retention has been screened out and that hydro-dynamic retention is small. 

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