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Experimental And Mathematical Studies Of Cyclic Solvent Injection To Enhance Heavy Oil Recovery
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Book Synopsis Experimental and Mathematical Studies of Cyclic Solvent Injection To Enhance Heavy Oil Recovery by : Zhongwei Du
Download or read book Experimental and Mathematical Studies of Cyclic Solvent Injection To Enhance Heavy Oil Recovery written by Zhongwei Du and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: It has been suggested that Cyclic Solvent Injection (CSI) is a highly promising technique to recover heavy oil resources at which other recovery techniques are not economically or efficiently available. Therefore, it is necessary to conduct experimental and mathematical studies on the CSI for effective heavy oil recovery purposes. Experimental and data regression studies have been conducted to investigate the effects of the wormhole on the CSI. Nine tests were completed using three sand-pack physical models with different dimensions. Experimental results suggest that the oil production can be divided into two phases: solvent chamber rising phase and solvent chamber spreading phase. The average production rate in the solvent chamber rising phase is proportional to the wormhole length, while the average production rate in the solvent chamber spreading phase does not change much with the wormhole length. In addition, a relation of the oil production rate to the drainage height is obtained by regression analysis and verified with a different experiment. It is suggested that for a rectangular model, the oil production rate in the chamber rising phase is proportional to h1.1667. Experimental study of effects of pressure decline rate on the CSI has been performed. Twelve tests with ten decline rates through linear and non-linear pressure-drawdown methods were conducted. Results of optimizing the pressure decline rate indicated that the pressure decline rate plays a primary role in the CSI by affecting solvent chamber growth, foamy oil flow performance in Phase 1, and pressure drop force in Phase 2. Different driving mechanisms in different phases lead to different optimum pressure decline rates. Comparison of two pressure-drawdown methods suggests that the main difference between the non-linear pressure-drawdown method and linear pressuredrawdown method is that the former cannot provide a continuous driving force for diluted oil as well as the latter. The effect of the intermittent driving force is much more significant in Phase 2. Therefore, production performance of tests of pressure-drawdown linearly was generally better than that of tests of pressure-drawdown non-linearly. A linear material balance equation of CSI has been proposed to obtain the recovery factor of diluted oil. It is successfully used to obtain the recovery factor of diluted oil of each cycle for a well-designed CSI test in a rectangular physical model (80×40×20 cm3). The relation of the solution-gas oil ratio and the diluted oil formation volume factor with pressure under non-equilibrium state are obtained through linear regression based the material balance equation. They are successfully verified through experimental data of a CSI test in a cylindrical model. Results indicate that the efficiency of oil dilution increases from 4.75% to 10.70% before the Cycle 10. Then it slightly varies from 10% to 16.25% till the Cycle 25. It is dramatically decreased 10.11% in the last five cycles. For first three cycles, the diluted oil recovery factor is up to 40% due to extended production time. Then it almost keeps around 32% till the Cycle 25. Three mixture solvent with the decline rate of 12.5 kPa/min ,5 kPa/min and 1 kPa/min have been conducted. Knowledge of production performance of mixture solvent CSI tests is obtained through the comparison of mixture solvent tests with different decline rate and the comparison between mixture and pure solvent tests. Pure solvent tests had larger recovery factor and average oil production per cycle than mixture solvent tests. The asphaltene precipitation and production time significantly impacted the recovery factor of diluted oil in mixture solvent tests.
Book Synopsis Cyclic Hot Solvent Injection Method to Enhance Heavy Oil Recovery Based on Experimental Study by : Kewei Zhang
Download or read book Cyclic Hot Solvent Injection Method to Enhance Heavy Oil Recovery Based on Experimental Study written by Kewei Zhang and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the solvent-based heavy oil recovery methods, the cyclic solvent injection (CSI) method has been acknowledged as an effective method with high oil production rate. Oil recovery in pure solvent CSI study is as high as over 70%. However, injection pressure in the pure solvent CSI is limited by the low dew point pressure of hydrocarbon at laboratory ambient temperature condition. In the mixture gas CSI method, although the solvent dew point pressure can be raised at the ambient temperature condition, recovery factor of this method is much lower than that of pure solvent CSI method. Therefore, it is necessary to explore an alternative CSI method which takes advantage of both pure gas-based and mixture gas-based CSI methods. As raising the pure solvent injection temperature can increase the solvent dew point pressure, the idea of hot solvent CSI is experimentally tested in this study. This new type of CSI method is named the cyclic hot solvent injection method (CHSI). In the CHSI laboratory study, hot solvent can reach high initial reservoir pressure. The experimental system consists of a sand-pack model unit, injection unit, production unit and data acquisition unit. Three major topics have been studied concerning CHSI: the comparison between CHSI and the replaceable method of CHSI (the mixture gas CSI method), the comparison between CHSI and the "N-Solv" (hot vapor solvent extraction) method, and temperature sensitivity analysis in CHSI. Experimental results show that, for the first topic, oil recovery of CHSI method is much higher than it is in mixture gas CSI method; for the second topic, oil production performance of CHSI is compared with that II in N-Solv; for the third topic, three solvent injection temperature levels are compared with each other in order to study solvent temperature effect on the oil production performance. Experimental results show that the CHSI method is an effective heavy oil extraction method, because this method is superior to mixture gas CSI method and N-Solv method regarding oil recovery. Oil recovery of CHSI is hardly influenced by solvent injection temperature. However, solvent injection temperature positively affects oil production rate during early CSI production period.
Book Synopsis Experimental and Numerical Investigation of Cyclic Solvent Injection (CSI) Performance in Heavy Oil Systems In The Presence of Wormhole Networks by : Nathan Abraham David
Download or read book Experimental and Numerical Investigation of Cyclic Solvent Injection (CSI) Performance in Heavy Oil Systems In The Presence of Wormhole Networks written by Nathan Abraham David and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis An Improved Vapour Solvent Injection Technique for Enhanced Heavy Oil Recovery by : Tao Jiang
Download or read book An Improved Vapour Solvent Injection Technique for Enhanced Heavy Oil Recovery written by Tao Jiang and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Sustainable In-Situ Heavy Oil and Bitumen Recovery by : Mohammadali Ahmadi
Download or read book Sustainable In-Situ Heavy Oil and Bitumen Recovery written by Mohammadali Ahmadi and published by Elsevier. This book was released on 2023-03-24 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sustainable In-Situ Heavy Oil and Bitumen Recovery: Techniques, Case Studies, and Environmental Considerations delivers a critical reference for today’s energy engineers who want to gain an accurate understanding of anticipated GHG emissions in heavy oil recovery. Structured to break down every method with introductions, case studies, technical limitations and summaries, this reference gives engineers a look at the latest hybrid approaches needed to tackle heavy oil recoveries while calculating carbon footprints. Starting from basic definitions and rounding out with future challenges, this book will help energy engineers collectively evolve heavy oil recovery with sustainability applications in mind. Explains environmental footprint considerations within each recovery method Includes the latest hybrid methods such as Hybrid of Air-CO2N2 and Cyclic Steam Stimulation (CSS) Bridges practical knowledge through case studies, summaries and remaining technical challenges
Book Synopsis Experimental Testing of Solvent Assisted Cyclic Steam Injection in Heavy Oil Reservoirs by : Nirbendra KC
Download or read book Experimental Testing of Solvent Assisted Cyclic Steam Injection in Heavy Oil Reservoirs written by Nirbendra KC and published by . This book was released on 2017 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Hybrid Enhanced Oil Recovery Processes for Heavy Oil Reservoirs by : Xiaohu Dong
Download or read book Hybrid Enhanced Oil Recovery Processes for Heavy Oil Reservoirs written by Xiaohu Dong and published by Elsevier. This book was released on 2021-10-27 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hybrid Enhanced Oil Recovery Processes for Heavy Oil Reservoirs, Volume 73 systematically introduces these technologies. As the development of heavy oil reservoirs is emphasized, the petroleum industry is faced with the challenges of selecting cost-effective and environmentally friendly recovery processes. This book tackles these challenges with the introduction and investigation of a variety of hybrid EOR processes. In addition, it addresses the application of these hybrid EOR processes in onshore and offshore heavy oil reservoirs, including theoretical, experimental and simulation approaches. This book will be very useful for petroleum engineers, technicians, academics and students who need to study the hybrid EOR processes, In addition, it will provide an excellent reference for field operations by the petroleum industry. Introduces emerging hybrid EOR processes and their technical details Includes case studies to help readers understand the application potential of hybrid EOR processes from different points-of-view Features theoretical, experimental and simulation studies to help readers understand the advantages and challenges of each process
Book Synopsis Advanced methods of mathematical modeling and experimental study in oil and gas reservoirs by : Fuyong Wang
Download or read book Advanced methods of mathematical modeling and experimental study in oil and gas reservoirs written by Fuyong Wang and published by Frontiers Media SA. This book was released on 2023-07-05 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Optimum Cyclic Solvent Injection (CSI) and Waterflooding/Gasflooding in the Post Cold Heavy Oil Production with Sand (Chops) Reservoirs by : Hongze Ma
Download or read book Optimum Cyclic Solvent Injection (CSI) and Waterflooding/Gasflooding in the Post Cold Heavy Oil Production with Sand (Chops) Reservoirs written by Hongze Ma and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, the technical synergy of combining cyclic solvent injection (CSI) and waterflooding (WF) or gasflooding (GF) in a two-well configuration for the post-cold heavy oil production with sand (CHOPS) reservoirs was explored. In the experiments, the original heavy oil samples were collected from the Colony and McLaren formations in Alberta, Canada. The PVT data and viscosities of CH4/CO2/C3H8-saturated Colony/McLaren heavy oil were measured at different equilibrium pressures and Tres = 21 °C. A total of 17 sandpacked laboratory tests were conducted to examine the technical and economical merits of the combined CSI and WF/GF. Both the CSI + WF and CSI + GF recovered more heavy oil than the CSI or WF alone due to the extended foamy-oil flow. The combined CSI and WF outperformed the combined CSI and GF in terms of the heavy oil recovery factor (RF), heavy oil production rate, and cumulative gas-oil ratio (GOR) because gas channeling was hindered by the subsequently injected water. In addition, C3H8 was found to be a more dissolving and extracting solvent than CO2 due to its more favourable PVT properties and larger heavy oil viscosity reduction. The intermediate pressure drawdown rate or CO2 injection rate resulted in a higher heavy oil RF during the CSI or GF. Theoretically, an analytical material balance model (MBM) was formulated to predict the cumulative heavy oil and gas productions and the average reservoir pressure during the primary production and subsequent CSI. The non-equilibrium phase behaviour and the foamy-oil properties were taken into account in this analytical MBM. Several unknown parameters were tuned and determined by best matching the theoretically predicted data and the experimentally measured data, such as the nucleation coefficient of dissolved CH4 in the heavy oil and the decay coefficient of dispersed CH4 bubbles from the heavy oil. The predicted cumulative heavy oil productions and average reservoir pressures during the primary production and subsequent CSI agreed well with the measured data. However, there were large discrepancies between the predicted and measured cumulative gas productions in the CSI because of its gas channeling, which is a major technical issue encountered in the CSI. In addition, it was found that dissolved CH4 in the heavy oil became the dispersed CH4 bubbles more quickly when the nucleation coefficient was larger at a higher pressure drawdown rate or in a less viscous heavy oil. The foamy heavy oil with the dispersed CH4 bubbles was more stable when the decay coefficient was smaller at an increased pressure drawdown rate or in a more viscous heavy oil. Numerical simulations were undertaken to optimize the CSI, CSI + WF, and CSI + GF after the primary production in a representative and synthetic field-scale heavy oil reservoir by choosing the net present value (NPV) as an objective function. The steepest ascent (SA) method and the particle swarm optimization (PSO) were utilized to find the optimum well controls and maximize the NPV. Both the SA method and PSO efficiently determined nearly optimum NPVs for the CSI, CSI + WF, and CSI + GF in the heavy oil reservoirs with/without the wormholes. It was found in this study that the NPV of the CSI + GF was the highest in the post-CHOPS reservoir. The oil producer should be operated at the minimum allowable bottom hole pressure (BHP) during the entire reservoir life. The gas injector should be used to inject at the maximum allowable injection rate during the early cycles but shut in during the late cycles to control the gas channeling.
Book Synopsis Enhanced Solvent Vapour Extraction Processes in Thin Heavy Oil Reservoirs by : Xinfeng Jia
Download or read book Enhanced Solvent Vapour Extraction Processes in Thin Heavy Oil Reservoirs written by Xinfeng Jia and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Application of Different Types of Solvents for Heavy Oil Recovery by : Kwang Hoon Baek
Download or read book Application of Different Types of Solvents for Heavy Oil Recovery written by Kwang Hoon Baek and published by . This book was released on 2020 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt: Various challenges in heavy oil recovery come from the low mobility of reservoir oil. For example, the heavy-oil displacement by water results in a large mobility ratio and therefore, inefficient volumetric sweep. Polymer flooding is the traditional method to improve the frontal stability of the oil displacement, but the polymer mobility is often optimized to be greater than the oil mobility because increasing the polymer viscosity adversely affects the oil production rate. The low mobility of reservoir oil also results in a large amount of steam required in steam-assisted gravity drainage (SAGD), one of the commercially successful methods of bitumen recovery. This research investigated the application of unconventional solvents for heavy oil recovery, such as dimethyl ether (DME), organic alkalis, and surface active solvents (SAS), as a potential additive to the injection fluid. These solvents are not conventionally used for enhanced oil recovery (EOR). The first part of the dissertation presents potential methods of improving the efficiency of SAGD by using water-soluble solvents. Phase-behavior data were obtained for mixtures of bitumen and water-soluble solvents. Experimental results indicated that use of organic alkalis at low concentrations (e.g., 0.5 wt% pyrrolidine) in low-salinity brine can yield efficient emulsification of bitumen in water. The affinity of the organic alkali for asphaltic bitumen was important for oil-in-water emulsification at a wide range of temperatures. The second part of the dissertation presents a potential method of improving polymer flooding by SAS that reduces the interfacial tension (IFT) between the oleic and aqueous phases. Results showed that the IFT reduction by three orders of magnitude (i.e., 15.8 to 0.025 dynes/cm) gave a reduced residual oil saturation and a delayed polymer breakthrough in polymer flooding experiments with no preceding water flood. When the straight polymer flooding resulted in an oil recovery factor of 47% at 1.0 pore-volume injected (PVI), the SAS-improved polymer flooding increased it to 63% with a SAS slug of 0.1 wt% for 0.5 PVI or 0.5 wt% for 0.1 PVI
Book Synopsis Optimal Solvent and Well Geometry for Production of Heavy Oil by Cyclic Solvent Injection by : Jin Xiu Qi
Download or read book Optimal Solvent and Well Geometry for Production of Heavy Oil by Cyclic Solvent Injection written by Jin Xiu Qi and published by . This book was released on 2005 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Characterization of Gas-Oil Flow in Cyclic Solvent Injection (CSI) for Heavy Oil Recovery by : Sam Yeol Hong
Download or read book Characterization of Gas-Oil Flow in Cyclic Solvent Injection (CSI) for Heavy Oil Recovery written by Sam Yeol Hong and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cyclic Solvent Injection (CSI) has emerged as an effective post-CHOPS recovery method. It has shown a great potential with the aid of the solvent injection under the huff-n-puff operation. The use of solvent that maintains a strong nature of gas results in the solvent chamber which under the huff-n-puff operation locates at an inner region towards the well. The CSI process is therefore governed by the gas-oil flow as the solvent chamber is dominated by the free gas-oil flow and the heavy oil zone by the dispersed gas-oil flow referred to as the foamy oil flow. The gas-oil flow in CSI eventually appears as the combined flow of free gas and foamy oil across the solvent chamber. The gas-oil flow in heavy oil systems has been widely investigated based on heavy oil solution gas drive. However, the combined flow of free gas and foamy oil in CSI considerably differs from that in heavy oil solution gas drive and therefore needs to be investigated separately. The differences mainly arise as in CSI the free gas originates from the solvent chamber whereas in heavy oil solution gas drive it evolves from solution gas. Consequently, the combined flow of free gas and foamy oil in CSI yields the characteristics that strongly depend on the pressure depletion rate and the growing solvent chamber. This study is aimed at characterizing the gas-oil flow in CSI for heavy oil recovery at different pressure depletion rates under the effect of the growing solvent chamber. To fulfill the objective, the gas-liquid relative permeability curves are inferred with the use of numerical simulations by history-matching seven lab-scale CSI tests performed at varying pressure depletion rates. The foamy oil behavior is taken into account by applying the modified-fractional flow model. This study therefore not only demonstrates the distinct properties of the gas-oil relative permeability curves in CSI process but also the applicability of the modified-fractional flow model. The sensitivity analysis is performed to examine the phenomena responsible for the distinct behavior of the gas-oil flow in CSI.
Book Synopsis Petroleum Abstracts. Literature and Patents by :
Download or read book Petroleum Abstracts. Literature and Patents written by and published by . This book was released on 1990 with total page 1416 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Experimental Study of the Effect of Composite Solvent and Asphaltenes Contents on Efficiency of Heavy Oil Recovery Processes at Injection of Light Hydrocarbons by : Dmitry N. Borisov
Download or read book Experimental Study of the Effect of Composite Solvent and Asphaltenes Contents on Efficiency of Heavy Oil Recovery Processes at Injection of Light Hydrocarbons written by Dmitry N. Borisov and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The current state of research in the field of solvent injection techniques for increase of heavy oil production efficiency is discussed in the chapter. As a result of a series of experiments on the physical modeling of oil displacement processes in a porous medium in large-sized model, features of asphaltene precipitation and the formation of fixed residual oil upon injection of solvent based on light alkanes are revealed. The oil displacement by n-hexane was studied and the difference in the composition of residual oil in the zones of dispersion and diffusion has been shown. The influence of the composition of asphaltenes peculiarities on the dynamics of oil recovery and on the accumulated oil recovery during the injection of n-hexane, as well as the composition and quantity of asphaltenes precipitated in the porous medium, has been estimated. The effect of toluene and nonylphenol additives on the proportion of asphaltenes in the residual oil and cumulative oil recovery has been evaluated using the Ashalchinskoye field oil as an example of heavy oil in the physical modeling of injection of n-hexane as the base solvent.
Book Synopsis Study of Hydrocarbon Miscible Solvent Slug Injection Process for Improved Recovery of Heavy Oil from Schrader Bluff Pool, Milne Point Unit, Alaska. Final Report by :
Download or read book Study of Hydrocarbon Miscible Solvent Slug Injection Process for Improved Recovery of Heavy Oil from Schrader Bluff Pool, Milne Point Unit, Alaska. Final Report written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The National Energy Strategy Plan (NES) has called for 900,000 barrels/day production of heavy oil in the mid-1990s to meet our national needs. To achieve this goal, it is important that the Alaskan heavy oil fields be brought to production. Alaska has more than 25 billion barrels of heavy oil deposits. Conoco, and now BP Exploration have been producing from Schrader Bluff Pool, which is part of the super heavy oil field known as West Sak Field. Schrader Bluff reservoir, located in the Milne Point Unit, North Slope of Alaska, is estimated to contain up to 1.5 billion barrels of (14 to 21[degrees]API) oil in place. The field is currently under production by primary depletion; however, the primary recovery will be much smaller than expected. Hence, waterflooding will be implemented earlier than anticipated. The eventual use of enhanced oil recovery (EOR) techniques, such as hydrocarbon miscible solvent slug injection process, is vital for recovery of additional oil from this reservoir. The purpose of this research project was to determine the nature of miscible solvent slug which would be commercially feasible, to evaluate the performance of the hydrocarbon miscible solvent slug process, and to assess the feasibility of this process for improved recovery of heavy oil from Schrader Bluff reservoir. The laboratory experimental work includes: slim tube displacement experiments and coreflood experiments. The components of solvent slug includes only those which are available on the North Slope of Alaska.
Book Synopsis Role of C3H8 and CH4 in Enhancing the Foamy Oil Phenomena and Performance of CO2-Based Cyclic Solvent Injection in Heavy Oil Systems by : Arash Ahadi
Download or read book Role of C3H8 and CH4 in Enhancing the Foamy Oil Phenomena and Performance of CO2-Based Cyclic Solvent Injection in Heavy Oil Systems written by Arash Ahadi and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: As light oil resources are continuously depleted, heavy oil exploitation is nowadays being put on agenda to meet the ever-increasing energy demand. Cyclic Solvent Injection (CSI) technique holds great promise as a viable approach to produce heavy oil from thin reservoirs where thermal and gravity-dominated recovery methods fail to sufficiency (and economically) recover oil. CSI, with CO2 being used as the solvent, has become a subject of several investigations and considerable speculation in light oil systems. Nevertheless, not too many studies ventured into realm of application of CO2 in heavy oil systems. In addition, importance of C3H8 and CH4 in the injected CO2 stream has been addressed in the literature; however, the details of the optimum mixing ratio of these two hydrocarbon solvents are the main knowledge gap that needs to be addressed. In this study, series of cyclic injection tests of pure CO2, CH4-CO2, C3H8-CO2, C3H8-CH4, and C3H8-CH4-CO2 were conducted at various operating pressures and mixture compositions to different (in terms of viscosity) heavy oil samples. Sand pack models with absolute permeability of kabs = 6-10 D and porosity of ø = 27-32% were used as representatives of a typical heavy oil reservoir. It was attempted to measure the CO2/solvent apparent solubility, solvent-produced oil asphaltene content, duration of produced-oil foamy shape stability, and oil recovery in each cycle to probe into the trend of responsible mechanisms during each cycle of CSI. Results showed that there is an optimum pressure in cyclic CO2 injection process in heavy oil systems; the pressure beyond which the ultimate oil recovery factor (RF) did not notably improve (near 4.82 MPa in this study). Higher concentration of C3H8 in the CO2 stream improved the oil recovery during cyclic injection. However, ultimate RF was not noticeably increased when C3H8 concentration in the mixture exceeded a certain value (near 50 mole% in this study). Although C3H8 showed effective role on the performance of CSI, it was found that the recovery factor reduces with increased CH4 concentration in the CO2 stream. The highest recovery factor of 73.8% was obtained by injecting mixture of 50% C3H8 - 50% CO2 into 1850 mPa.s viscous oil sample under the operating pressure of Pinj = 1.72 MPa. The results of CSI tests on the heavy oil with viscosity of 6430 mPa.s were lower by almost 20% since the solvent solubility was noticeably lower. Performing C3H8-CH4 tests to 6430 mPa.s viscous oil revealed that there is an optimum fraction of C3H8 in CH4 stream (near 50 mole% in this study). Moreover, partially replacement of C3H8 with CO2 (50% C3H8 - 50% CH4 with 30% C3H8 - 40% CH4 - 30% CO2) was effective (and profitable) as the achieved ultimate RF were more or less the same. No oil production was observed after conducting the first cycle injection of optimum quantified solvents on oil with the viscosity of 22 000 mPa.s. Small values of Solvent Utilization Factor (SUF), relatively high values of Solvent Oil Ratio (SOR), and low quality of the produced oil in the last cycles suggest that higher cycle numbers of CSI in heavy oil reservoirs is depending on the economic limits and might be conducted cautiously.
