Synthesis and Evaluation of a Low Molecular Weight Amphiphilic Polymer for Enhanced Oil Recovery

Abstract

In this work, a novel, low molecular weight amphiphilic polymer (LAP) with high content of surface‐active functional groups was developed, and its effectiveness for emulsion‐based enhanced oil recovery (EOR) in relatively low permeability reservoirs was evaluated. The LAP polymer can potentially be synthesized on an industrial scale through a free radical polymerization reaction between acrylamide (AM), methyl acrylate (MAA), and the unsaturated surfactant monomer 2‐(acylamido)‐dodecane sulfonic acid (C12AMPS). The interfacial tension between 1000 mg L−1 LAP water solution and Bohai crude oil at 50 °C was reduced to a low value of around 0.2 mN m−1. Core flooding tests were also conducted to study the EOR potential and migration properties of LAP in porous media. The resistance and residual resistant factors of 1500 mg L−1 LAP solution were measured to be 51.0 ± 0.1 and 16.5 ± 0.1, respectively, suggesting LAP's great potential to be used for reservoir profile control. In addition, oil recovered from a three‐layer heterogeneous core by LAP solution was found to be comparable to that recovered using alkaline‐surfactant‐polymer (ASP) flooding. It is also worth mentioning that to accommodate different reservoir conditions, the molecular weight of LAP is adjustable by modifying the concentration of chain transfer agent, surfactant monomer, or initiator.

Effect of Interface Structure and Behavior on the Fluid Flow Characteristics and Phase Interaction in the Petroleum Industry: State of the Art Review and Outlook

“…The gas–liquid interface of foams is widely used in the petroleum industry because of its high viscosity and low density . Particularly, after using ASP technology, residual oil is present as a low-permeability layer above the formation. , Because macromolecular chemicals cannot enter the microporous space, residual oil trapped in the reservoir pores cannot be removed. While foam flooding can expand the wave volume, especially in nonhomogeneous reservoirs, its displacement efficiency is relatively low .…”

Synthesis and characterization of a novel active polymer for enhanced oil recovery

“…These features are due to the active groups introduced into the polymer molecular chain, which can improve sweep efficiency and oil‐washing efficiency simultaneously and overcome the problem of chromatographic separation in polymer–surfactant binary flooding. Chen 47 synthesized a novel low‐molecular‐weight surface‐active polymer by using AM, methyl acrylate, and 1‐acrylanmido‐2‐methyl propane sulfonic acid (AMPS) through free‐radical reaction. They confirmed that it has potent activity and great application prospect in profile control and oil displacement.…”

Development of Novel Star-Like Branched-Chain Acrylamide (AM)-Sodium Styrene Sulfonate (SSS) Copolymers for Heavy Oil Emulsion Viscosity Reduction and Its Potential Application in Enhanced Oil Recovery

“…The multipoint adsorption of surface active units of the amphiphilic polymer at the heavy oil/water interface is at less dosage (0.05− 0.15 wt %) for the stability of the emulsion than conventional surfactants. 2 Amphiphilic polymers with heavy oil viscosity reduction properties have been widely used in enhanced heavy oil recovery in Bohai Bay, China. 3 Li et al 4 prepared a series of water-soluble amphiphilic polymers with strong hydrogen bonds, polar functional groups, and acrylamide.…”

“…Previously, we reported that the amphiphilic polymer AM-MAA-C 12 AMPS could reduce the oil–water interfacial tension and improve the oil recovery efficiency. The multipoint adsorption of surface active units of the amphiphilic polymer at the heavy oil/water interface is at less dosage (0.05–0.15 wt %) for the stability of the emulsion than conventional surfactants …”

“…Amphiphilic polymers have an oil displacement character of in situ emulsion formation . Previously, we synthesized AM-MAA-C 12 AMPS amphiphilic polymer viscosity reducers with different molecular weights and the adaptability of the molecular weights of amphiphilic polymers to reservoir permeability was studied; the oil displacement efficiency of amphiphilic polymers was equivalent to the alkaline–surfactant–polymer (ASP) flooding system. The fluid produced was convenient for demulsification; the amphiphilic polymer viscosity reducer has the best result combined with cyclic steam injection .…”