Alkali/Surfactant/Polymer Flooding in the Daqing Oilfield Class II Reservoirs Using Associating Polymer

Abstract

Hydrophobically modified associating polyacrylamide (HAPAM) has good compatibility with the Daqing heavy alkylbenzene sulfonate surfactant. The HAPAM alkali/surfactant/polymer (ASP) system can generate ultralow interfacial tension in a wide range of alkali/surfactant concentrations and maintain stable viscosity and interfacial tension for 120 days. The HAPAM ASP system has good injectivity for the Daqing class II reservoirs (100–300 × 10−3 μm2) and can improve oil recovery by more than 25% on top of water flooding. In the presence of both the alkali and the surfactant, the surfactant interacts with the associating groups of the polymer to form more micelles, which can significantly enhance the viscosity of the ASP system. Compared with using HPAM (Mw = 2.5 MDa), using HAPAM can reduce the polymer use by more than 40%.

Review on Polymer Flooding: Rheology, Adsorption, Stability, and Field Applications of Various Polymer Systems

“…Feng et al 144 synthesized hydrophobic PAM containing 0.5% hydrophobic monomer cetyl dimethylallyl ammonium chloride. Thermal stability was measured for 120 days and the polymer was found to be stable, but the investigation was conducted at a temperature of 45 • C. High temperature data are not available and it is expected that the polymer is not stable at higher temperatures due to the absence of any other monomer which can protect AM.…”

Hydrophobically associating polymers for enhanced oil recovery – Part B: A review of modelling approach to flow in porous media

“…The use of HAPAM polymers for Alkaline Surfactant Polymer (ASP) flooding is not common compared to the use of HPAM polymers (Feng et al, 2013;Guo et al, 2017). aged for a period of 120 days, the viscosity of the associative polymer is improved however, the interfacial tension remained the same.…”

“…Therefore, the surfactants present in the ASP system interacts with the hydrophobic components of the associative polymer thereby resulting in more intermolecular association, which significantly increases the viscosity of the fluid as shown in Figure 7. However, it should be noted the rheological improvement of ASP system containing associative polymers depend on type and composition of the surfactant (Feng et al, 2013). In addition, the composition and type of hydrophobic monomer in the associative polymer is also important when considering the performance of HAPAM-ASP system.…”

“…Core flooding results for the ASP system containing associative polymer as studied by Feng et al (2013). Figure 6: The effect of alkali on the viscosity of the associating polymer solution (Feng et al, 2013) Figure 7: The effect of alkali mixed surfactant on the status of the associating polymer solution (Feng et al, 2013) Figure 8: Flow of a polymer with its Molecular Weight Distribution (MWD) at the inflow, in a porous media and outflow. The thick square box represents the porous media with the changing MWD of the polymer subject to changing flow conditions.…”

Optimization of Surfactant Sodium Lignosulfonate (SLS) Synthesis from Waste Biomass of Pulp and Paper Industry by Response Surface Methodology (RSM)

“…Lignin was the main component of wood, besides cellulose and hemicellulose. Lignin consists of three monomers namely p-coumaryl alcohol (H), coniferil alcohol (G) and sinapyl alcohol (S) 4 (Feng, 2014). Lignin was also formed by polymerization of monomers which differ in structure according to the type of plant 5 (Gao, 2014).…”