Novel self‐assembling polymeric system based on a hydrophobic modified copolymer: formulation, rheological characterization, and performance in enhanced heavy oil recovery

Abstract

This work presents the chemical formulation and rheological properties of a novel self-assembling polymer (SAP) system derived from a hydrophobically modified sulfonated polyacrylamide (HMSPAM). This polymeric association was established through complexation between the pendant hydrophobic groups contained in HMSPAM and β-cyclodextrin molecules. The new SAP system offers improved viscoelastic properties because of the "interlocking effect" of the hydrophobic groups into β-cyclodextrin cavities. It also provides suitable reformability upon mechanical shear when compared to the base HMSPAM. Furthermore, SAP exhibits superior tolerance to elevate brine salinity and hardness, as well as high reservoir temperature. Sandpack flooding tests conducted at simulated reservoir conditions (Pelican Lake reservoir, Alberta, Canada) indicate that this system shows superior mobility control (resistance factor) compared to HMSPAM. It also shows potential as in situ permeability modifier, which makes this polymeric system particularly suitable for heavy oil recovery applications. For instance, the newly developed SAP produced 20% more incremental heavy oil recovery if compared to the performance of the commonly used partially hydrolyzed polyacrylamide and 7% more incremental oil recovery than the baseline HMSPAM at the same experimental conditions. Overall, this new self-assembly system shows potential for applications in heavy oil recovery.

Nanostructured Particles for Controlled Polymer Release in Enhanced Oil Recovery

“…This viscosity increase at higher temperatures may also be the effect of copolymer structure. It has been observed previously that the presence of hydrophobic moieties in HPAM chains induced their self‐assembly at increased temperature, which likely enhances macroscopic viscosity.…”

Supramolecular linear polymer formed by host–guest interactions of β-cyclodextrin dimers and polyacrylamide end-capped with adamantane

“…Romero-Zerón et al [17] investigated the chemical formulation and rheological properties of a novel self-assembling system for enhanced heavy oil recovery comprised of HAPAM and β-CD.…”

Design of Tailor‐Made Water‐Soluble Copolymers for Enhanced Oil Recovery Polymer Flooding Applications

“…Enhanced oil recovery (EOR), which is also called tertiary oil recovery, encompasses the implementation of various techniques in order to increase the efficiency of oil extraction from oil fields. Among various EOR techniques, polymer flooding (which is also called polymer‐augmented flooding) is well recognized for its versatility and popularity and has been applied in many oil fields with a long commercial history and proven results …”

“…Acrylamide homopolymers (including partially hydrolyzed acrylamide) and copolymers of AAm (such as AAm/AAc) make the largest contribution in oil recovery processes because of their availability and low cost . AAm homopolymer is slightly positively charged in acidic pH medium and therefore it has a tendency to adsorb onto reservoir porous media, such as rocks and sands that are negatively charged .…”