Investigation on the Adaptability of the Polymer Microspheres for Fluid Flow Diversion in Porous Media

Abstract

Large amounts of water producing from producers have been a great concern for petroleum engineers.In an attempt to inhibit water production and promote oil productivity, various water control agents and techniques have been devised for enhanced oil recovery purpose for decades with some good successes reported commercially. Mainly field-targeted specifically, however, these chemicals are limited in expansive reservoir applications for failing to tolerate harsh formation conditions of high temperature (HT) and high salinity (HS). Besides, their low injectivity is also another proper impediment. In this presentation, we synthesized a new agent of polymer microspheres using inverse emulsion polymerization technique to divert fluid patterns in deep porous media for reservoirs encountered recovery enhancement problems. These microspheres are made to tolerate HT and HS conditions, and can be pumped into deep pore space with relative ease. With the help of nuclear magnetic resonance (NMR) and nuclear pore membrane filtration techniques, a series of experimental procedures were conducted to test the adaptability of newly produced polymer microspheres to targeted pore structure in enhancing the sweeping efficiency of injection fluids. Both laboratory core tests and NMR data show good characteristics of polymer microspheres in modifying injection profile, demonstrating a good capability to divert fluid flow patterns in deep porous media and enhance oil productivity.

The Reservoir Adaptability and Oil Displacement Mechanism of Polymer Microspheres

“…Polymer microspheres are well-known for their heat resistance, salt resistance, shear resistance, and strong deep migration ability [19,20]. The polymer microspheres adopted in profile control are mainly nano-sized and micro-sized.…”

Investigation on Plugging and Profile Control of Polymer Microspheres as a Displacement Fluid in Enhanced Oil Recovery

“…When the particle size of the PMs is too small, it is difficult to block the high permeability layer. Therefore, many researchers have conducted studies on optimizing the particle size of the polymer microspheres to increase the efficiency of PMs flooding [27][28][29][30][31].…”

“…As seen in Figure 1, previous studies have taken the pore throat size of the core and the particle size of PMs as fixed values [28,32]. In fact, the pore structure of the core is very complex, with different pore throat sizes [33][34][35].…”

Degradable cross-linked polymeric microsphere for enhanced oil recovery applications

“…5 Presently, the cross-linked polymer microspheres served to provide in-depth conformance control have attracted more attentions because of many merits such as size-controlled, highly swelling, tolerant to temperature and salinity and environmentally friendly. 6,7 However, N-methylene bisacrylamide (NMBA) was used as crosslinkers in conventional polymer microspheres, which led to microspheres just swell but do not dissolve in contact with water, resulting in poor mobility control within deep formation. 8,9 In 1999, the Bright Water microspheres in which the conformation was constrained by two types of crosslinkers, was introduced.…”