Polymer Flooding Research Articles

A novel integrated methodology for screening, assessment and ranking of promising oilfields for polymer floods

A novel integrated methodology for screening, assessment and ranking of promising oilfields for polymer floods

Economical evaluation of oil recovery by applying polymer flooding

Chemical oil recovery methods are based on mainly three different products, polymers that increase the aqueous phase viscosity, surfactants that reduce interfacial tension between oil and aqueous phases, and alkalis that produce in-situ surfactants when combined with the oil phase acids. Chemical oil recovery methods are often used after waterflooding. Based on this context, this research aims to study the application and comparison of both waterflooding, and Polymer flooding based on a rough economic analysis, such as Net Pay Value (NPV) criteria. To do so, this study used a semisynthetic reservoir model, using characteristics and values like those found in a Brazilian northeast basin. Polymer flooding (PF) was studied at different concentrations, injection rates and sequences through numerical reservoir simulation and was compared to the most profitable scenarios of continuous water flooding (WF). The NPV analysis considered two different prices of barrel of oil, considering the oscillation of international prices. Results showed that polymer flooding improves the amounts of oil recovery at the three used concentrations when compared to WF and that the highest profit was obtained when the lowest PF concentration was injected continuously from the beginning of the reservoir´s productive life. Nevertheless, WF obtained a low difference in terms of NPV when compared to PF´s, but it achieved its highest value one year before PF, leading to a frequent decision regarding to choose between the higher delayed profit or a lower but faster income.

Assessment of World’s First Two Polymer Injectivity Tests Performed in Two Giant High-Temperature/High-Salinity Carbonate Reservoirs Using Single-Well Simulation Models and Pressure Falloff Tests Analysis

Summary Polymer flooding is a mature enhanced oil recovery (EOR) technology that has been widely implemented around the world for more than 60 years. Polymer flooding mostly targets medium- to high-permeability sandstone reservoirs with moderate salinity, hardness, and temperatures. However, in the last few years, the envelope of polymer flooding has been expanded to harsher reservoir conditions of high-temperature and high-salinity mixed-wet to oil-wet heterogeneous carbonate reservoirs. Development of novel polymers and innovative field application concepts has allowed for the reconsideration of polymer-based EOR as a promising technology to improve sweep efficiency for these challenging reservoirs. Polymer injectivity is one of the key challenges for polymer flooding projects and requires a rigorous derisking program that includes laboratory and field testing. A comprehensive laboratory program was designed to assess and investigate polymer thermal stability, polymer rheology in porous media, adsorption, and injectivity using reservoir core samples. In addition, two polymer injectivity tests (PITs) were performed in two giant light oil (0.3 cp) carbonate reservoirs in onshore Abu Dhabi under harsh conditions of high salinity (>200 g/L), high divalent ions (>20 g/L), high temperature (>250°F), and H2S concentration of up to 40 ppm. The polymer used during the two PITs (PIT 1 2019 and PIT 2 2021) is a new generation of EOR polymer (SAV 10) with high 2-acrylamido-tertiary-butyl sulfonic acid content that was specifically developed to tolerate such harsh conditions. This paper is focused on the interpretation of the PITs and lessons learned for future polymer-based EOR projects. The detailed data acquired in both tests were used to evaluate the polymer injectivity at representative field conditions and in-depth mobility reduction. The PITs together with the extensive laboratory studies are part of a thorough derisking program for the upcoming world’s first innovative hybrid EOR multiwell pilots—simultaneous injection of miscible gas and polymer (SIMGAP) and simultaneous injection of water and polymer (SIWAP). Both PITs are composed of three stages that include a multirate waterflood baseline, polymer injection using different rates, and polymer concentrations followed by extended chase waterflooding. In addition, a sequence of multiple pressure falloff (PFO) tests was acquired during the PIT executions and analyzed to obtain the required uncertainty parameters for the history-matching exercise. Polymer preshearing was considered as part of both PIT programs with the aim to homogenize the polymer molecular weight distribution and reduce possible shear-thickening effects near the wellbore as per laboratory measurements. Two single-well 3D simulation models were built to incorporate the information from polymer laboratory studies and to interpret the large field data sets acquired during the PITs. Lessons learned from PIT 1 allowed us to optimize the PIT 2 design program and achieve better understanding of polymer characteristics. The interpretation of the pressure transient analysis (PTA) of the PFO tests and the 3D simulation models of the two PITs confirmed the generation of polymer banks and demonstrated effective propagation of the polymer into the reservoirs at target concentrations and representative rates of the future SIWAP and SIMGAP interwell pilots.

Modification of Welan gum with poly(2-oxazoline) to obtain thermoviscosifying polymer for enhanced oil recovery

Thermoviscosifying polymers refer to a category of smart materials that exhibit a responsive behavior to environmental stimuli, specifically demonstrating a natural rise in viscosity of solutions as the temperature increases. The temperature-dependent behavior exhibited by thermally viscous polymers renders them potentially advantageous in the context of Enhanced Oil Recovery (EOR). There exists a dearth of research pertaining to the application of thermoviscosifying polymer for better recovery in reservoirs characterized by high temperatures and high salt content. In order to tackle the mentioned concerns, this study examined the utilization of welan gum modified with poly(2-oxazoline) as thermally responsive chain segments to enhance viscosity. The objective was to evaluate the ability to enhance viscosity under thermal conditions and to assess their effectiveness in displacement of reservoir oil in high temperature and high salt environments. This study aimed to establish a theoretical framework for understanding the correlation between the molecular structure and performance of novel thermally viscous polymers. Additionally, it sought to offer practical insights into designing the molecular structure of thermally viscous polymers suitable for polymer flooding in high temperature and high salt environments. Furthermore, the study proposed the application of these new thermoviscosifying polymers for EOR.

Development of Novel Silicon Quantum Dots and Their Potential in Improving the Enhanced Oil Recovery of HPAM.

Hydrolyzed polyacrylamide (HPAM) is commonly used in polymer flooding, however, it is prone to viscosity reduction at high temperatures and high salinities, weakening its ability to improve oil recovery. In this work, sulfonated modified silicon quantum dots (S-SiQDs) were synthesized and then added to HPAM to study the improvement of rheological properties and enhanced oil recovery performance of HPAM at high temperatures and salinities. It is found that the S-SiQDs with a concentration of only 0.1 wt % can significantly increase the viscosity of HPAM from 28.5 to 39.6 mPa·s at 60 °C and 10,000 mg/L NaCl. Meanwhile, the HPAM/S-SiQDs hybrid solution always possessed higher viscosity and viscoelastic moduli than HPAM, attributed to the hydrogen bonding between HPAM and S-SiQDs. Notably, HPAM/S-SiQDs still maintained elastic behavior at harsh conditions, indicating that they formed a strong network structure. Through oil displacement experiments, it was found that the oil recovery of HPAM/S-SiQDs was higher (28.3%), while that of HPAM was only 17.2%. Thereafter, the utilization sequence of oil during the displacement process was studied with nuclear magnetic resonance experiments. Ultimately, the oil displacement mechanism of HPAM/S-SiQDs was deeply analyzed, including viscosity thickening and wetting reversal.

Preparation of sodium alginate encapsulated anionic polyacrylamide microcapsules with delayed thickening performance

Polyacrylamide (PAM) is a polymer compound that is widely used in oil extraction, wastewater treatment, food processing and other fields. As a typical polymer flooding agent, PAM has received much attention in the field of oil extraction due to its unique of viscoelastic properties. However, polymer flooding faces several challenges in oil reservoirs, including high injection pressure, high shear loss and crossflow. In an effort to overcome this challenge, we designed a method of coating Ca2+ cross-linked sodium alginate onto the core structure of polyacrylamide, providing shear resistance and sustained release performance for the polymer. The important role of the shell material was indirectly demonstrated by measuring its apparent viscosity using digital rotary viscometer. Moreover, the swelling behavior of microcapsules in water was observed using an optical microscope. The protective shell made the slow release of anionic PAM into water under stirring at 500 rpm, maintaining the viscosity of the fluid below 10 mPa·s within 2 h, and the viscosity increased from 1.8 mPa·s to 30 mPa·s after 35 h. In addition, this work revealed the importance of effective encapsulation by emulsification/external gelation method and a facile shell modification by the layer-by-layer self-assembly method.

Study on Main Factors Controlling Development Performance of Heterogeneous Composite Flooding in Post-Polymer Flooding Reservoir

Heterogeneous composite flooding has performed well with regard to enhanced oil recovery after polymer flooding in recent years. In order to significantly increase oil recovery, the development parameters should be designed differently for each well. However, it is difficult to rapidly allocate development parameters through the lowering of computational costs. Therefore, the authors of this paper carried out research to clarify the main controlling factors of parameter allocation. Firstly, the numerical simulation domain was separated into several regions, with injection wells and production wells at the center of each region. The statistical parameters of each region were calculated. Then, the water injection rate, liquid production rate, and chemical agent concentration were allocated based on the proportion of statistical parameters in each region. A large number of development schemes were designed by combining different injection and production allocations that were calculated based on each statistical parameter. Finally, the development performance of each scheme was simulated and analyzed. The statistical parameters corresponding to the best performance scheme were regarded as the main controlling factors of heterogeneous composite flooding after polymer flooding. These results showed that the main controlling factors for the allocation of the water injection rate were pore volume and permeability variation coefficient. The main controlling factors for liquid production rate were the remaining oil saturation, formation coefficient, and reservoir pressure. The main controlling factors for chemical agent concentration were pressure and permeability variation coefficient. These findings concerning the main factors controlling development parameter allocation were validated by practical application in several well groups of an actual reservoir model. This study provides references for improving heterogeneous composite flooding performance for post-polymer flooding reservoirs in the future.

Combinational CO2 and Polymer Injections for EOR and CO2 Storage in Depleted Reservoirs: A Mini Review on Laboratory, Simulation and Field Studies

Water-alternating-gas is commonly used in most of the existing enhanced oil recovery (EOR) projects in the world to regulate gas mobility and reduce fingering problems. Unfortunately, the expected recovery factor from most of the fields could not be attained with such EOR method. Development strategies of mature oil fields during the energy transition period may therefore involve the combination of polymer and CO2 injections to achieve incremental oil recovery and at the same time provide longterm geological storage solution for carbon. This paper therefore presents overview of the processes of polymer and CO2 floodings, and then highlights the overall benefits to be derived from the combination of CO2 and polymer flooding techniques in depleted hydrocarbon reservoirs, especially oil reservoirs. Reviews on studies related to the combinational CO2 and polymer injections are then carried out. Highlights of areas of the combinational CO2 and polymer injections needing more attention are also mentioned.

On approaches to solving problems when modeling polymer flooding at the Kalamkas oil field

Background: Currently, polymer flooding is one of the most effective methods for increasing reservoir recovery, accordingly and modeling this process is of particular relevance.
 Aim: The purpose of hydrodynamic modeling is to predict the distribution of parameters, technological indicators, and simulate all possible development scenarios. Based on the simulation results, decisions are made on the profitability of projects.
 Materials and methods: There are a number of significant problems in the process of hydrodynamic modeling, one of which is adaptation. Difficulties with adaptation are mainly associated with the incorrect determination of filtration – capacitive properties, which is directly caused by the lack of core research data. The main physical parameters that determine the filtration-capacitive properties of reservoir rocks are porosity, permeability, relative phase permeabilities, and saturation. These properties are critical for accurate fluid flow modeling and production forecasting. However, the lack of core data limits our understanding of these properties and affects the quality of model fit.
 Due to the insufficient data on the oil field in this Vostok site of horizon Ю-1 of the Kalamkas field, the approved initial geological reserves differ from the reserves according to the model by approximately 20%. For a more accurate adaptation of the hydrodynamic model, the availability of current initial geological reserves is significantly insufficient.
 Results: In this article, a number of approaches were applied to solve the above-mentioned problem in the hydrodynamic modeling of polymer flooding in the Kalamkas oil field, and as a result, the results obtained were demonstrated.
 Conclusion: Hydrodynamic modeling allows us to conduct numerical experiments to optimize the parameters of polymer flooding, helps to study their influence and select the optimal ratio to improve the efficiency of the flooding process.

Study on the channeling limit of polymer flooding in the conglomerate reservoir

The conglomerate reservoirs are known for their high degree of heterogeneity, which poses a challenge during polymer injection. Fluids tend to channel along dominant paths leading to premature appearance of polymer in the oil well. This phenomenon results in a rapid increase in water cut, leading to wastage of the polymer. Currently, there is no reliable method for identifying polymer channeling in such conglomerate reservoirs. To address this issue, this paper conducts physical simulation experiments on parallel cores under varying heterogeneous conditions based on the geological characteristics of the reservoir. The study analyzed and statistically evaluated the distribution ratio, water cut, and polymer concentration in the output under varying heterogeneous conditions. This analysis identified the distribution ratio and polymer concentration as key indicators of polymer channeling. Based on these findings, a comprehensive discriminant diagram of polymer channeling was established. The study found that the coefficient of permeability variation (CV) was the primary factor contributing to channeling. This diagram can be used to understand the underlying principles of polymer channeling and provide technical guidance for developing effective profile control schemes and optimizing site construction strategies.

Evaluation of the development effect of polydynamic drive in Class IIB oil reservoir of Lamadian Oilfield

With the continuous deepening of oilfield development, the target of oilfield development is gradually shifting towards reservoirs with poor physical properties, and polymer flooding can better utilize such reservoirs.The heterogeneity of Class II B oil layer in Lamadian Oilfield is severe, and polymer flooding takes effect later, with a small decrease in watercut.A study was conducted on the evaluation of polymer flooding development effectiveness for Class II B oil layers through reservoir numerical simulation . Research has shown that when the initial watercut is constant, a lower injection pressure can increase the utilization degree of remaining oil in the middle and high permeability layers of Class II B oil layers. With the increase of injection pressure, the response time is shortened, and the decrease in watercut is reduced; As the watercut increases, the injection pressure should gradually increase in order to improve the recovery of low permeability reservoirs;As the watercut increases, the injection pressure should gradually increase in order to improve the recovery of low permeability oil layers;At a watercut of 95% and injection pressure of 7MPa, a field experiment was conducted with a molecular weight polymer of 12 million , and the response time was 6 months. The cumulative oil increase was 14675m3, achieving good polymer flooding effect.

ОЦЕНКА КРИТЕРИЕВ ПРИМЕНЕНИЯ ПОЛИМЕРНОГО ЗАВОДНЕНИЯ В ОСЛОЖНЕННЫХ ПЛАСТАХ. ОБЗОР

Selection of the enhanced oil recovery method is based on applicability criteria, which are referred to in foreign literature as screening. To select the technology, the geological and physical parameters of the field are compared with the existing limits of applicability of the technology. Polymer flooding is a physical and chemical method of enhanced oil recovery, which has been used on an industrial scale for more than 60 years. The paper compares the applicability criteria of classical polymer flooding, adopted in the literature from 1985 to 1997, with modern projects carried out in the world. The main criteria, in terms of stability of polymer solution in reservoir conditions, key criteria determining the possibility of injecting the solution and additional criteria are highlighted. The main emphasis is made on the expediency of polymer flooding in high-temperature reservoirs containing low-viscosity oil or water of high mineralisation. Realised projects of enhanced oil recovery using polymers over the last 10 years are presented. Due to the appearance of modified representatives of high molecular weight compounds a large number of polymer flooding projects have been carried out in a wide range of conditions, which are presented in this paper: at reservoir temperature up to 140˚C, oil viscosity from 0.07 to 10000 mPa*s, as well as with highly mineralised formation water up to 250 g/l. Considering the implemented projects, it was revealed that the impact on increasing waterflood coverage is achieved not only by equalising the mobility of oil and displacing agent, but also by redistributing filtration flows of injected fluid from highly permeable and, consequently, already flushed zones to less permeable zones containing a large amount of residual reserves.

Application of flow-diversion technologies to increase oil recovery at the Uzen field

Polymer flooding is a highly effective method of physical and chemical intervention in productive reservoirs. The primary characteristic of polymers is their ability to thicken water, which reduces the viscosity ratio between oil and water in the formation and diminishes water breakthrough conditions caused by viscosity differences or reservoir heterogeneity. Additionally, due to their increased viscosity, polymer solutions can more effectively displace both oil and bound reservoir water from the porous medium. They interact with the porous medium’s framework, including the rock and the cementing substance, leading to the adsorption of polymer molecules onto the surface of the porous medium. This adsorption blocks the channels or hinders water filtration within them. The extent of adsorption is significantly influenced by water mineralization and the rock’s mineral composition, necessitating the creation of a fringe from fresh water to reduce adsorption. Despite this, the positive aspect of adsorption in water-washed formations is evident, as it decreases permeability and aligns the pickup profile, which is particularly beneficial for conditions like those in the Uzen deposit. The article presents an analysis of the effectiveness of Flooding Displacement Technology (FDT) in this context.

Technology Focus: EOR Modeling (January 2024)

The oil and gas industry is at a critical juncture in addressing the pressing need to balance operational efficiency with environmental stewardship. With the world’s growing emphasis on climate change and sustainability, the industry is tasked with the dual objectives of refining operational efficiency and simultaneously diminishing its carbon footprint. This balancing act has become a strategic imperative crucial for the long-term viability of the industry. In light of the recent COP28 agreement, which emphasizes a “swift, just, and equitable energy transition,” the role of low-emission enhanced oil recovery (EOR) and operational optimization becomes increasingly significant. This period of transition, which may span several decades, demands a pragmatic approach where the existing hydrocarbon resources are used as efficiently and responsibly as possible. In the quest to optimize operations and reduce carbon footprint, three innovative technical papers present a cohesive story of advancement through modeling and machine learning. These papers underscore the industry’s shift toward more efficient practices, each contributing a crucial piece to the larger puzzle of EOR.The first paper introduces an advanced modeling approach for fractured reservoirs, a significant development in tight rock simulations that simplifies fracture heterogeneity characterization and enhances computational efficiency, crucial for optimizing asset development decisions in shale and tight oil resources. Building on the theme of efficiency, the second paper pivots to the realm of surfactants, exploring their role in wettability alteration within unconventional liquid-rich reservoirs. This research provides a systematic approach for screening thermally stable surfactants under reservoir conditions, crucial for improving hydrocarbon recovery without unnecessary field trials. The final piece of this narrative is a study using machine learning to predict gas-injection parameters in EOR processes. This approach addresses the lack of extensive gas-injection laboratory data, demonstrating the power of data-driven predictions in enhancing operational efficiency and decision-making. These papers weave a compelling narrative of technological innovation, highlighting the role of advanced modeling and machine learning. As the oil and gas industry progresses in its vital mission to supply the world’s energy needs, the pivotal role of technology innovation becomes increasingly evident. Advanced technologies focused on operational optimization and reducing carbon emissions are essential in reinforcing the industry’s adaptability and resilience in the context of this rapidly evolving energy landscape. Recommended additional reading at OnePetro: www.onepetro.org. SPE 215083 An Analytical Tool to Predict Fracture Extension and Elastic Desaturation for Polymer Field Projects by M.B. Abdullah, The University of Texas at Austin, et al. SPE 216822 First Pilot Design of Low-Tension-Gas (LTG) Flooding in Carbonate Field in North Oman by Mohammed Al-Abri, Petroleum Development Oman, et al. SPE 213037 Field-Scale Multistage and Multiobjective Optimization of Rate and Concentration for Polymer Flooding by Ruxin Zhang, Texas A&M University, et al.

Research on the timing of polymer flooding oil and water well fracturing

Fracturing technology is the main measure to increase production and injection in oilfield production. With the gradual expansion of the scale of polymer flooding, the proportion of fractured Wells also increases year by year. How to maximize the benefits of fracturing measures has become the key technology, and the timing of fracturing is a major factor affecting the fracturing effect. By studying the fracturing time and effect of fracturing Wells in the industrial zone of polymer flooding, the optimal fracturing time of injection-production Wells is given. The fracturing time of injection Wells should be dominated by blank water drive stage and water-cut decline period. The producing Wells with low liquid production strength and low flow pressure are suitable for whole-well fracturing in water-cut decline period, and the thick-injection-thin production Wells dominated by river channels are suitable for fracturing in low-water cut period. Thin and differential Wells with differential production are suitable for fracturing during water-cut recovery period.

Enhanced Oil Recovery in the Field A123 by Using the Injection of Alkaline, Surfactant and Polymers

Abstract This paper is based on numerical simulations in order to improve the total oil production of field A123 by using an Alkaline-surfactant and polymer (ASP) injections method. The main objective of this paper is to carry out reservoir simulations job that will further permit to conclude if producing oil and gas in this field will be rentable or not. To achieve this objective, the computer Modelling Group software version 2015.10 (CMG 2015 software) is used to carry out the field numerical simulations. Based on the tests run, one injection well is selected and used as a main injector in order to execute the chemical injection schemes in the field. Four different scenarios are studied such as natural flow of oil as the base case (primary oil production), polymer flooding, alkaline-surfactant (AS) flooding and ASP flooding are considering in the injection process and important results from simulator are analyzed and interpreted. Sensitivity analyses are done especially focusing on chemical solution concentration, injection rate and duration of injection time. The results obtained shows an oil recovery factor (ORF) of 64.1554 for polymer flooding, 64.2026 for alkali-surfactant finally 64.8056 for the combined flooding (ASP flooding), respectively. Those results have a direct influence on reservoir pressure which changes after the injected fluids are introduced in the reservoir and therefore improve the production rate. By evaluating the feasibility of the project of polymer flooding combined to AS flooding considering oil prices fluctuations due to COVID 19, the net present value (NPV) is 873 484 102 USD which is the best for the field A123.

Enhanced Oil Recovery in the Field A123 by Using the Injection of Alkaline, Surfactant and Polymers

Abstract This paper is based on numerical simulations in order to improve the total oil production of field A123 by using an Alkaline-surfactant and polymer (ASP) injections method. Its main objective is to carry out reservoir simulations job, that will further permit to conclude if producing oil and gas in this field will be profitable or not. To achieve this objective, the Computer Modelling Group software version 2015.10 (CMG 2015 software) is used to carry out the field numerical simulations. Based on the tests run, one injection well is selected and used as a main injector in order to execute the chemical injection schemes in the field. Four different scenarios are studied such as natural flow of oil as the base case (primary oil production), polymer flooding, alkaline-surfactant (AS) flooding and ASP flooding are considering in the injection process and important results from simulator are analyzed and interpreted. Sensitivity analyses are done especially focusing on chemical solution concentration, injection rate and duration of injection time. The results obtained shows the base case simulations shows that, the reservoir produce oil naturally for 26 years for a quantity of 3,749,204.82 bbl and 864,412,318 SCF of gas. With the most significant case in the third scenario, the coupled effect of ASP optimize the quantities to 32,364,440.2 bbl for oil and 7,459,728,710 scf of gas produce. Also the oil recovery factor (ORF) is 64.1554% for polymer flooding, 64.2026% for alkali-surfactant and 64.8056% for the combined ASP flooding, respectively. These results have a direct impact on reservoir pressure which changes after the injected fluids are introduced in the reservoir and therefore improve the production rate. Thus, the feasibility of the project of polymer flooding combined to AS flooding, is up to 873,484,102 USD for the field A123.

Prospects for the effective use of fly ash in the technological processes of oil and gas production

The problem of efficient use of coal fly ash (CFA) is a global environmental problem that requires urgent attention and immediate action to address it. Research shows that huge amounts of CFA are generated every year, but only 25% of the waste is recycled. To overcome this alarming situation, there is a need to focus on increasing the use of coal ash in various industries. The promising uses of coal ash in construction, electronics, resource recycling, wastewater treatment, agriculture and other industries require further research. Of particular interest is the use of coal ash in industrial processes for the extraction of hydrocarbons. The physical, chemical and mineralogical properties of ash, such as its morphology, surface area, porosity and chemical composition, make it an ideal material for various field processes. Increasing the use of coal ash in various industries and its use in industrial processes for the extraction of hydrocarbon raw materials will significantly increase the level of utilization and reduce the negative impact on the environment. Keywords: coal fly ash; CFA; waste; hydrocarbon production; polymer gels; polymer flooding; enhanced oil recovery; nanoparticles; foam compositions; cementing compositions.

Analysis of the results of field tests of viscoelastic compositions under the conditions of a complex terrigenous reservoir in the Caspian sea

The publication analyzes the use of viscoelastic systems in order to increase the efficiency of oil production in the Caspian fields. The conducted studies of the results of pilot field work on the introduction of polymer flooding technologies in complexly constructed terrigenous reservoirs have shown a number of disadvantages of the systems used at the pilot site. In particular, the premature destruction of the polymer compositions used and the subsequent sharp watering of the extracted products were revealed. The research covers technology tests from November 2014 to October 2021, the results of which established the presence of deteriorating dynamics in the removal of polymer material, in addition, the study revealed a high influence of thermobaric and reservoir conditions on the polymer formation process and its subsequent properties. The classic solution to the described problem is the use of compositions with higher viscosity indices, however, laboratory experiments with the use of reservoir fluid have shown a decrease in the characteristics of the compositions used while maintaining conditions close to reservoir conditions. Based on the results of the research, an approach based on a systematic solution of the problem was proposed, the existing line of agents was modernized taking into account experimental data with the reaction of compositions to reservoir fluids, including elements of control and regulation of the oil recovery process during exposure, changes in the volumes of injected polymer solutions. Keywords: water intrusion; systemic approach; viscoelastic systems; oil recovery.

Evaluating Factors Impacting Polymer Flooding in Hydrocarbon Reservoirs: Laboratory and Field-Scale Applications.

Polymer flooding is an enhanced oil recovery (EOR) method used to increase oil recovery from oil reservoirs beyond primary and secondary recovery. Although it is one of the most well-established methods of EOR, there are still continuous new developments and evaluations for this method. This is mainly attributed to the diverse polymers used, expansion of this method in terms of application, and the increase in knowledge pertaining to the topic due to the increase in laboratory testing and field applications. In this research, we perform a review of the factors impacting polymer flooding in both laboratory studies and field-based applications in order to create guidelines with respect to the parameters that should be included when designing a polymer flooding study or application. The main mechanism of polymer flooding is initially discussed, along with the types of polymers that can be used in polymer flooding. We then discuss the most prominent parameters that should be included when designing a polymer flooding project and, based on previous laboratory studies and field projects, discuss how these parameters impact the polymer itself and the flooding process. This research can provide guidelines for researchers and engineers for future polymer flooding research or field applications.