Abstract
The biopolymers and synthetic polymers are available as concentrated solutions, gels, crushed powders, beads and partially pre-crosslinked solid microgels. All of them are notorious of their poor solubility and jointly with their incompatibility in porous systems often causes serious formation damage hard to cure. Therefore, searching such formulations, which eliminate the mentioned drawbacks, may contribute significantly to improvement of polymer technologies. One of the possible options is the application of "liquid" polymer.
The "liquid" polymer is a stabilized suspension of bead-like polymers in organic solvent with active content of 40–45%. The polymer beads are monodispersed and have narrow size distribution (2–4 μm). Usually anionic and nonionic tenside mixtures are used to stabilize the dispersion. The laboratory studies focused on dissolution phenomena, colloid chemical, rheological, and flow properties in porous media (sandstone) of polymer solutions prepared by different "liquid" polymers. Based on the experimental findings, it was found that using "liquid" polymers readily and rapidly dissolve in water, the solutions are free of microgels and mechanical entrapment was minimal in low permeable sandstone cores. In addition, they decrease the surface tension to 30–35 mN/m, the interfacial tension lowering was min. one order of magnitude, and they proved to be compatible with other chemicals (e.g. silicates). In additions, the rheological and flow properties were identical or very similar to those data obtained by conventional solid polymers.
The extra beneficial properties of "liquid" polymers may significantly contribute to improvement of polymer-based technologies; meanwhile the surface facilities can be simplified and the chemical cost remains the same. The "liquid" polymer was successfully applied in water shutoff and conformance treatments in oilfields (Oman), but its use is also recommended in smart water flooding and chemical EOR methods.
