Figure - available from: Polymer Bulletin
This content is subject to copyright. Terms and conditions apply.
![Injection profile of the micellar polymer flooding method (from [48])](publication/318187188/figure/fig2/AS:960061958533167@1605908016783/Injection-profile-of-the-micellar-polymer-flooding-method-from-48.gif)
Source publication
![Injection profile of the micellar polymer flooding method (from [48])](publication/318187188/figure/fig2/AS:960061958533167@1605908016783/Injection-profile-of-the-micellar-polymer-flooding-method-from-48_Q320.jpg)
In this paper, the current advances in chemical injection method of polymer flooding are reviewed. The ultimate goal of polymer flooding for EOR process is to improve tertiary oil recovery by increasing the overall oil driving efficiency as a result of the improvements in injected fluid’s viscosity and mobility ratio. However, it was found that the...
Similar publications
In this paper, physical and numerical simulations were applied to investigate the polymer degradation performance and its effect on polymer enhanced oil recovery (EOR) efficiency in homogeneous reservoirs. Physical experiments were conducted to determine basic physicochemical properties of the polymer, including viscosity, rheology, and degradation...
The oil and gas sector is one of the six core industries in India. These industries are of strategic importance and plays a vital role in influencing decisions across other important spheres of the economy. But the overall production has declined due to the increase in maturity of the oil reservoirs. In developing countries like India, the oil prod...
Since the introduction of viscous/capillary concepts by Moore and Slobod (1956), several modifications and advancements have been made to the capillary number (Nc) so that it could have a better correlation with residual oil saturation (Sor) during enhanced oil recovery (EOR). In subsequent years, laboratory-scale studies have indicated that the vi...
The hydrolyzed polyacrylamide (HPAM) is the most often used polymer in Enhanced Oil Recovery (EOR) activities. The molecular weight of HPAM has a direct relationship with the molecular size and the permeability of the porous media through the polymer will be injected. The polymer flooding has been documented in EOR process for different types of ge...
Polymer flooding is an enhanced oil recovery (EOR) method that reduces the mobility ratio between the displaced oil and the displacing injected water. The flow of polymer solutions through porous media is subject to some process-specific phenomena, such as the inaccessible pore volume (IAPV). Due to IAPV, polymer molecules move faster through the p...
Citations
... Almost half of the world's oil reservoirs are carbonates, which are naturally fractured-with low matrix permeabilityand mostly have high temperature and salinity [3]. The most popular water-soluble polymers for EOR-including synthetic (e.g., partially hydrolyzed polyacrylamide (HPAM), HPAM copolymers with other acrylic monomers such as N-vinyl pyrrolidone [4,5], copolymers based on polyether [6], hydrogels [7], and hyperbranched polymers [8]) and natural or biobased polymers (e.g., xanthan, guar gum, and Arabic gum [9])-are not usually applicable for carbonate oil reservoirs [10]. The essential characterizations for polymers to be applied in carbonate reservoirs are small molecular size (to provide enough injectivity), high resistance to shear, mechanical degradation, temperature, and salinity along with enough molecular weight and water solubility [11]. ...
... This morphology is because of phase separation between the hydrophilic core and hydrophobic shell polymer [29]. According to Tamsilian et al. [7] and Saboori et al. [28], the hydrophobic shell of CS nanoparticles is non-soluble in water. Hence, the injected aqueous phase to the reservoir has a viscosity nearly equal to pure water. ...
To improve the efficiency of hydrophilic polymers in oil reservoirs, a method encapsulates the polymer within a protective shell, safeguarding the core polymer and enabling controlled release in demanding, high-temperature conditions. Poly(N-isopropylacrylamide) nanoparticles are encapsulated with polystyrene shells through emulsion polymerization in this study. Varying the amounts of shell monmer and crosslinking agents resulted thick, sphere-shaped shells with homogeneous morphology, which protects the core polymer and enabling controlled release. Structural and morphological properties are characterized using Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (H¹NMR), dynamic light scattering (DLS), and scanning electron microscope (SEM) imaging. Increasing the styrene amounts lead to larger particles, while higher crosslinker amounts result in a narrower size distribution. Thermal testing indicates heat resistance up to 300 °C, suitable for enhanced oil recovery (EOR) applications. Rheological tests determine an optimal 30-day release for the PNIPAM core, with the CS polymer showing increased viscosity under harsh conditions. The colloidal stability model estblished by Derjaguin, Landau, Verwey, and Overbeek (DLVO theory) and experimental results demonstrate good stability and energy barriers at room temperature, but decreased stability and increased agglomeration at higher temperatures. Thickening the styrene shell leads to particle agglomeration and unsuitable stability. The study confirms the effectiveness of the model in analyzing CS colloidal latex systems.
Graphical Abstract
... Thus, a further 5-35% of the total oil reserve is expected to be recovered in the tertiary stage. To further improve the recovery rate of oil, the chemical [2,3] , thermal [4] , polymer [5,6] , microorganism [7,8] , and particle gel [9,10] ooding methods are widely used in the tertiary stage, which is usually referred as the enhanced oil recovery (EOR) process. ...
More than 50% of the crude oil is trapped inside the pores of the rock after the primary and the secondary oil recovery stage, various methods have been currently used for enhanced oil recovery (EOR) to recover the trapped oil. Brine injection, as the most commonly used approach in EOR, was heavily influenced by the concentration of active ions like Ca ²⁺ , Mg ²⁺ , and SO 4 ²⁻ . In this study, two kinds of polydimethylsiloxane (PDMS)-based microfluidic devices were designed and fabricated to mimic the porous structure in order to study the active ion’s impact in the brine flooding process. Since the PDMS is transparent in the visible range, the fluid flow inside the fabricated porous structure can be observed directly during the brine flooding process. The effect of active ions including Ca ²⁺ , Mg ²⁺ , and SO 4 ²⁻ in the brine flooding process was studied in detail with the microfluidic devices. The proposed method could have wide application potential in the screening of flooding reagents in the oil industry.
... (iv) The ternary mixture within conventional chemical EOR is called alkali-surfactant-polymer (ASP) flooding which is made by injecting alkali, surfactant and polymer solutions for the purpose of enhanced oil recovery (EOR). Such compatibility of the mentioned fragments in the introduced slug ensured this method as the universally accepted most productive chemical EOR method [55]. The first step in this process is adding alkali and surfactant solution into formation that will help in cleaning up and getting rid of the residual oil trapped in pore spaces. ...
As we all know, numerous methods have been invented for better managing of the reservoirs to recover the trapped oil from them as much as possible. These techniques included primary techniques that were implemented primarily at the beginning of this industry. As these techniques were not effective enough, secondary techniques, like; water flooding and gas injection methods were created and the amount of recovered oil were increased, as well. On the contrary, the demand for more oil was raised up and it was felt that much more effective techniques are necessary. It resulted to creation of Enhanced Oil Recovery Techniques and these techniques are included; thermal methods (steam injection, steam assisted gravity drainage and in-situ combustion), Chemical methods (alkali flooding, surfactant flooding, polymer flooding, foam flooding, and combination of alkali-surfactant-polymer flooding), and microbial EOR. The most promising technique is microbial EOR because of being cost-effective and ecofriendly. GEMEOR (Genetically Engineered MEOR) and EEOR (Enzyme Enhanced Oil Recovery) are two new trends of MEOR that own potential hopes in petroleum industry.
... It can be seen that the steady injection pressure (2.48 MPa) is too high, while the initial viscosity retention rate (1.79%) of the effluent is too low, and the final stable viscosity retention rate is only 50%. In the test of conductivity, ISEPAM shows excellent properties, because ISEPAM has the self-crosslinking ability as a hydrophobic associative polymer [38,39]. ISEPAM solution flows slowly under low injection pressure conditions, and the effluent viscosity increases further with time. ...
The development of oil and gas resources in low-permeability reservoirs is being paid more and more attention. Moreover, oil and gas resources in low-permeability reservoirs are affluent, and the water cut of the medium permeability layer is so high that the injection capacity has decreased significantly. Therefore, it is of great importance to address the issues of injectability and enhance oil recovery in low-permeability reservoirs. Given the existing conditions of low permeability and high water cut in Daqing Oilfield, the synthesis of an in situ emulsified associative polymer (ISEPAM) is the focus of the research. The polymer was prepared by micellar polymerization, ensuring a molecular weight of 5 × 10⁶ Dalton. A series of experiments were conducted to investigate its dissolution filtration property, viscosifying, emulsification, anti-adsorption, conductivity, and oil displacement capacity. The experimental results show that ISEPAM has more significant properties than the polymeric surfactant (HB) used in Daqing Oilfield. The ISEPAM solution has significant filterability (filter factor is 1.1), viscosifying (38.66 mPa·s), emulsification (the water evolution rate of ISEPAM was only 4.4% for 60 min at 90% water cut), and good anti-adsorption property (after five adsorptions, still has a viscosity retention rate of 65%) in a specific concentration (1000 mg/L) and the field water in Daqing Oilfield (salinity is 4996.3 mg/L). The reason for this is due to the presence of dynamic reversible networks in the ISEPAM solution, and there are no cationic functional groups on the polymer chain. The conductivity of ISEPAM was tested using a homogeneous square core with 48.1 mD permeability, and the results show that the viscosity retention rate of the effluent can reach 90% and excellent injection property can be achieved. In the oil displacement test, ISEPAM presents excellent sweep efficiency and enhanced oil recovery by about 25% under 50 mD permeability. Under low permeability conditions, the ISEPAM exhibits better injectability and excellent oil displacement capacity. The related findings can provide an important idea and reference for the design and development of EOR polymers in the reservoirs with low permeability or high water cut.
... However, the conventional chemical EOR methods have their limitations [10][11][12]. Polymers whose main recovery mechanism is to increase the viscosity of injectants and consequently mobility, suffer viscosity loose in the presence of reservoir brines and elevated temperature conditions [13,14]. Surfactant and alkali lose their efficiency during their flow in porous media due to adsorption phenomena [15][16][17][18]. ...
... Polymers have become an essential part of human life due to their high-quality properties 1 and are widely used in various industrial fields and play a very important role. [2][3][4][5][6][7][8][9] There is no doubt that polymers are also used in major oil fields around the world. [10][11][12][13][14] Polymer flooding is mainly used to increase the viscosity of the replacement phase by injecting polymer solution into the formation, [15][16][17][18][19] which decreases the viscosity ratio of oil and water phases and then achieves the effect of controlling the rate of increase of water content in the extraction fluid. ...
In this work, indoor physical simulation experiments were used to examine the effects of shear, thermal, chemical, and microbial degradation on the properties of the hydrophobic associative polymer AP‐P4. It was discovered that the viscosity of the polymer solution generally decreased as the shear time was extended. The larger the shear strength, the lower the solution viscosity. Fitting of the nonlinear equation of solution viscosity with shear time, η = 12,988 t−1.08. When thermal degradation started, the solution viscosity first started to rise, however, this phase was just a short one. The viscosity of the solution gradually started to decrease as the thermal degradation period grew. In addition, the trends of properties like hydrokinetic radius, hydrophobic connectivity, and hydrolysis essentially followed the same patterns as those of solution viscosity. At the beginning of the degradation process, the viscosity retention of the polymer solution without oxygen is significantly higher than that of the aerobic environment. However, the difference between the two becomes smaller as the degradation time increases. In addition, the AP‐P4 had good temperature resistance and aging resistance capabilities when iron ions were present. Finally, it was discovered that AP‐P4 had a strong antibacterial effect, which decreased the viscosity brought on by microbial action.
... Mechanical degradation is one of the kinds of polymer degradation to which the solution is exposed during the injection process [28,29]. This occurs because the polymer presents a plastic deformation generated by internal friction in an area of high flow associated with abrupt pressure drops [30,31]. In the fluid path in the tubing from the surface to bottom, mechanical degradation occurs by the different accessories like valves and completion components [32,33] since at these points there is an increasing shear rate, Energies 2023, 16, 7565 3 of 19 ...
This work presents the proposal design for the completion of a polymer flooding injector well with waterflood flow regulator valves (FRV) in a Colombian field, based on experimental evaluations at the laboratory, intending to reduce the mechanical degradation suffered by the polymer solution at the time of injection, which allows to maintain the design parameters of the improved recovery project and reach the expected recovery factor. An analysis of the parameters and variables that influence the mechanical degradation of the polymer solution during the injection process (polymer solution concentration and the diameters of the FRV) was carried out using one laboratory methodology based on the recommended practices for the evaluation of polymers used in enhanced oil recovery operations API RP63. This work focuses on the following highlights: Evaluation of a waterflood flow regulator valve through experimental tests for polymer flooding and the designing of an initial well completion strategy to minimize mechanical degradation. The proposed valve and diameter resulted in a reduction of only 15 percentage points in the mechanical degradation of the polymeric solution when compared to a commercial water valve.
... [1][2][3] After secondary water flooding, a number of chemical enhanced oil recovery (EOR) flooding techniques are being examined due to their high cost and lack of resources, including surfactant flooding, polymer flooding, alkali-surfactant polymer (ASP) flooding, and micro-emulsion flooding. [4][5][6] Among them, polymer flooding technology has emerged as one of the most realistic and dependable methods for increasing recoverable reserves and stabilizing existing crude oil production. It involves injecting a small amount of watersoluble polymer, primarily by increasing the viscosity of the water phase and decreasing the permeability of the water phase to improve sweep efficiency and thus oil recovery. ...
Polymer flooding technology has become the most widely utilized chemical flooding technology in the world. The polymer structure gradually grows from linear to branched and hyperbranched as reservoir variability increases and polymer flooding technology advances. In this study, the nano-SiO2 was first controllably modified, and subsequently, a series of nano-SiO2 grafted modified polymers (MNSP) were synthesized using homogeneous aqueous solution polymerization with modified nano-SiO2 and another functional monomer. The rheological properties of MNSP were analyzed by using the MCR 301 rheometer; then, the mechanism of the influence of the concentration and the modification degree of nano-SiO2 on the rheological properties of MNSP was explored from the microscopic standpoint. The results demonstrate that at a salinity of 3 × 104 mg/L and temperature of 85 °C, the viscosity of the MNSP polymer is superior to that of the standard amphiphilic polymer APC16 whose synthesized monomers do not include nano-SiO2. When the concentration and the modification degree of nano-SiO2 were increased, the solution viscosity first increased and then decreased, and this is mostly due to the addition of inorganic nanoparticles, which stimulates the creation of a three-dimensional network structure and improves the solution characteristics of MNSP. However, too much modified SiO2 addition will interfere with polymerization between various monomers. The modification degree of the nano-SiO2 mostly influences the density of the polymer-formed network structure, the active sites on the modified nano-SiO2 surface rise as the degree of modification increases, as does spatial site resistance, resulting in inferior polymer characteristics. The findings of the experiments reveal fresh ideas for inorganic particles compounding organic polymers and expand the use area of polymers in the oilfield.
... On the other side, enhanced oil recovery (EOR) is the name given to the tertiary phase. 1 In actuality, a sizable amount of crude oil is still unrecovered following the primary and secondary phases of oil recovery. In order to increase the recovery from oil reservoirs, a tertiary recovery phase has been implemented. ...
... Consequently, chemical flooding as a secondary oil recovery technology has gradually become the primary enhanced oil recovery method and has been applied to old oilfields after water flooding. For instance, polymer flooding technology has been widely utilized in Daqing Oilfield since 1996, resulting in remarkable economic effects and confirming the feasibility of the technique in enhancing oil recovery in reservoirs after water flooding [1][2][3]. However, the oil reservoirs exhibit pronounced heterogeneity in both the horizontal and vertical directions after polymer flooding, leading to a significant challenge in profile control [4,5]. ...
After polymer flooding in Daqing Oilfield, the heterogeneity of the reservoir is enhanced, leading to the development of the dominant percolation channels, a significant issue with inefficient circulation, a substantial amount of displacement agents, and elevated cost. In order to further improve oil recovery, an adaptive oil displacement system (ASP-PPG) was proposed by combining preformed particle gel (PPG) with an alkali-surfactant-polymer system (ASP). This comprehensive study aims to assess the effectiveness of the adaptive oil displacement system (ASP-PPG) in improving the recovery efficiency of heterogeneous reservoirs after polymer flooding. The evaluation encompasses various critical aspects, including static performance tests, flow experiments, microscopic experiments, profile control experiments, and flooding experiments conducted on a four-layer heterogeneous physical model. The experimental results show that the adaptive system has robust stability, enhanced mobility, effective plugging capability, and profile improvement capability. Notably, the system demonstrates the remarkable ability to successfully pass through the core and effectively block the large pores, resulting in an 18.4% recovery incremental after polymer flooding. This improvement is reflected in the reduced oil saturation values in the ultra-high permeability, high permeability, medium, and low permeability layers, which are 5.09%, 7.01%, 13.81%, and 15.45%, respectively. The adaptive system effectively recovered the remaining oil in the low and medium permeability layers, providing a promising approach for improving the recovery factors under challenging reservoir conditions.
