The investigation of a new moderate water shutoff agent: Cationic polymer and anionic polymer

Abstract

Cationic polymers and anionic polymers were selected as a moderate water shutoff agent for water production control. Due to the adsorption of polymers on the sand surface, the adsorption capacity under static condition, in porous media, and adsorption morphology on mica were investigated through starch–cadmium iodide method, core flow test, and atomic force microscopy measurement. The adsorption quantity on the sand surface increased with the high polymer concentrations and long adsorption time. With the increase of temperature and shearing time, the adsorption capacity slightly decreased. In addition, the adsorption capacity under water wettability condition was significantly larger than that under oil wettability condition. Alternate injection of cationic polymer and anionic polymer caused larger adsorption capacity in the core test. An adsorption multilayer was formed through alternate adsorption of cationic polymer and anionic polymer confirmed by atomic force microscopy. The visual simulation experiment was also conducted to illustrate adsorption and enhanced oil recovery mechanism. The polymers preferentially entered the high permeability zone and adsorbed on the sand surface, thus enhanced oil recovery. Furthermore, alternate injection of cationic and anionic polymers as a moderate water shutoff agent was successfully applied for water production control in oilfield test. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39462.

High‐temperature‐resistant polymer gel system with metal–organic mixed cross‐linking agents

“…The cross‐linking mechanism involved in either metal or phenolic resin cross‐linker has been well documented . As reported previously, the carboxylate group (COO − ) in the polymer chain could be chelated with the metal Cr (III) species, resulting in the formation of a cross‐linked network structure . When WPF was used as a cross‐linker, either in a mixture of phenol and formaldehyde or a prereacted resin format, the amide groups of the polymer provide cross‐linking sites reacting with multiple hydroxymethyl groups on the phenolic ring, forming the gel system .…”

Gelation performance of poly(ethylene imine) crosslinking polymer–layered silicate nanocomposite gel system for potential water‐shutoff use in high‐temperature reservoirs

“…Generally, the effect of shearing on the gelation performance of a gel system is significant because shear degradation of the polymer takes place. Therefore, the gelation performance of a gel system will be obviously affected by the shearing . Nevertheless, gel sample 2A could also achieve the same high gel strength as the original gel sample, which may result from the reinforcing effect of the dispersed MMT layers in gel.…”

Effect of sodium dodecyl benzene sulfonate to the displacement performance of hyperbranched polymer

“…And then, the equilibrium concentration of each component was measured after centrifuging for 30 min at the speed of 3500 rpm. The polymer concentration was tested via the starch cadmium iodide method [26]. We chosen twophase titration method with mixed indicator to detect SDBS concentration after considering the effect of polymer on the SDBS concentration of binary system.…”