Day 3 Wed, March 23, 2022最新文献

{"title":"A Critical Review of Low Salinity Water Flooding for Offshore Applications and Potential Opportunities","authors":"Quan Chen, S. Ayirala, A. Yousef","doi":"10.2118/200237-ms","DOIUrl":"https://doi.org/10.2118/200237-ms","url":null,"abstract":"\u0000 Low salinity water flooding (LSWF) is an emerging enhanced oil recovery (EOR) technology with enormous potential for offshore applications. Numerous laboratory experiments and field trials of LSWF have been conducted to evaluate the EOR benefits and understand the underlying recovery mechanisms. The objective of this study is to provide a critical review on LSWF offshore field applications and summarize the key lessons learned. A review was also conducted on the capabilities of existing sulfate removal units for seawater injection in offshore fields. Furthermore, the potential of targeting offshore oil fields with de-sulfated seawater injection, either ongoing or planned, as primary candidates to switch over to LSWF EOR has been investigated.\u0000 For LSWF field trials, the chance of success can be significantly improved when it is based on key laboratory screening tests such as corefloods at reservoir conditions. The methodologies implemented for LSWF offshore field trials mainly involved Single Well Chemical Tracer Test (SWCTT) and inter-well field trials. However, the inter-well field trials implemented so far are restricted to unconfined pilots, which makes the production and injection allocation more difficult. Therefore, confined pilots are recommended for future consideration of LSWF field trials to provide better estimations on swept volume and improvements in the oil displacement efficiency.\u0000 Globally, there are more than 80 sulfate removal units currently in operation for offshore seawater flooding with approximately 10 million BWPD of cumulative de-sulfated seawater injection (DSSW) capacity for offshore water floods in the North Sea, the Gulf of Mexico, West Africa, and Brazil. All these fields with DSSW injection either ongoing or planned can become potential candidates to switch to LSWF EOR for the following two reasons: (1) The primary purpose for sulfate removal from sea water is to prevent scaling due to often high concentration of divalent cations in formation water and high sulfate concentration in seawater. The divalent cations can act as bridges between negatively charged rock surfaces and negatively charged polar oil components to increase the oil-wet tendency. These bridges become primary targets to be replaced by un-complexed cations in low salinity water for EOR. (2) The de-sulfated sea water injection process can easily be switched to LSWF by replacing the existing nanofiltration membranes in the sulfate removal facilities with reverse osmosis membranes and upgrading the facilities to increase the water treatment capacity and generate the desired low salinity water if these reservoirs fit the screening criteria and have a positive outcome of LSWF evaluation. Such retrofitting to the seawater treatment facilities on offshore platforms can bring significant gains to increase oil recovery with minimal additional investment.\u0000 The novelty of this study is that it provides some useful practical guidelines for reservoir screening","PeriodicalId":10912,"journal":{"name":"Day 3 Wed, March 23, 2022","volume":"82 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78597063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hazardous Events Prevention and Management Through an Integrated Machine Learning and Big Data Analytics Framework","authors":"Luca Cadei, Gianmarco Rossi, Lorenzo Lancia, D. Loffreno, A. Corneo, D. Milana, M. Montini, Elisabetta Purlalli, Piero Fier, Francesco Carducci, Riccardo Nizzolo","doi":"10.2118/200110-ms","DOIUrl":"https://doi.org/10.2118/200110-ms","url":null,"abstract":"\u0000 This paper reports the development and tests of an advance methodologies to predict Upstream plant risky events, such as flaring, applying an integrated framework. The core idea is to exploit Machine Learning and big data analytics techniques to tackle and manage both major upsets that would lead to significant inefficiency and loss. The tool is developed for complex upstream production system, where upset could be caused by a huge amount of heterogeneous factors, exploiting data driven monitoring systems to identify the weak signals of the upcoming events.\u0000 The framework proposed is mainly composed by a strong pipeline divided in 3 modules operating before (predictive phase), during and after the event. The former aims to reduce the probability of an event, the second works on the severity and the third one has a dual function: reporting upsets and feedback gathering system to be used to further improve the analytics implemented. The Predictive component alerts operators when it recognizes a dangerous pattern among the parameters considered. The other two components can support this one and can be exploited to detect early signs of deviations from the proper operating envelope, while predictive performances are not satisfying. Moreover, during an event occurrence, operators can promptly identify the causes of the upset through the entire production system. This allows a faster reaction and consequently a significant reduction in magnitude. The solution proposed provides 2 complementary methodologies:\u0000 an agnostic anomaly detection system, helping to map plant functional unit anomalous behavior, as a dynamic operating envelope, and identifying the most affected ones;\u0000 A real time root-cause analysis, as a vertical solution, obtained learning from the monitoring of the different specific functional unit;\u0000 The tool is also able to provide an automatic event register using information provided by the root-cause system, including operator feedbacks that will improve the performances of each module of the framework.\u0000 The entire pipeline developed has been applied on-line, working with real time data coming from an operating oilfield, with special focus on blowdown and flaring system. The robust architecture generated is able to overcome some main issues related to the complexity of Upstream production assets such as lack of data, quick dynamic of physical phenomena analysed and randomness of upsets. The first test demonstrates that the tool accuracy allows to identify and suggest actions on 35% of the most dangerous flaring events occurring. Moreover, the effectiveness increase significantly proving a real time root-cause analysis considering both strong and weak signals that cause dangerous overpressures through the treatment plant.","PeriodicalId":10912,"journal":{"name":"Day 3 Wed, March 23, 2022","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87854084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Novel Robust Polymer Gels for Water Shutoff Application in Sandstone Reservoir","authors":"Ayman Almohsin, Jin-Chao Hung, M. Bataweel, A. Abadi","doi":"10.2118/200266-ms","DOIUrl":"https://doi.org/10.2118/200266-ms","url":null,"abstract":"\u0000 Polymer gels is an effective method for water shut-off (WSO) application in sandstone oil reservoirs having high water cuts. WSO application can extend the economic life of the field once the undesired water production is minimized. A novel polymer gel was developed for water shut-off applications that extend the limitations of the current available materials for sandstone formation.\u0000 The new developed system offers chemical bonding of an organically crosslinked polymer gel to the sandstone rock surface, enabling the water shutoff system having enhanced stability with superior performance. The fluid system is low toxic and environmentally acceptable. It is comprised of polymer gel and adsorption components for sandstone formation, In order to enhance the blocking efficiency of WSO polymer gel, specific adsorption component for sandstone formation was introduced into the organically crosslinked polymer (OCP) gel. The gelant can be placed as a single phase, low-viscosity solution into the targeted formation zones. The new Polymer gel\u0000 Lab rheology study of the new developed polymer gel reveals that both the gelation time and the formed gel strength were greatly affected by the addition of the sandstone adsorption component. By using the appropriate retarder, the gelation time can be controlled without compromising gel strength. The new polymer gel was placed in haigh permeability sandstone core plug, and chase water was subseqyently injected to measure bloking capasity. The core flow test indicates substantial drops in water prduction. The new polymer system was able to withstand 3500 psi differential pressures at 200°F and did not allow the flow of water inside the core sample.\u0000 The new polymer gel system is expected to control water production through high permeability streaks and large pore openings. The system can be injected in porous media without injectivity reduction due to their low initial viscosity. This work provides significant insight using polymer gel system as an effective chemical treatments intended for carbonate substrate as water shutoff material.","PeriodicalId":10912,"journal":{"name":"Day 3 Wed, March 23, 2022","volume":"50 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86992402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experience on Application of Non-Metallic Materials for Offshore Facilities","authors":"Salvatore Montalto, P. Cavassi, Luca Ponteggia, M. Romano","doi":"10.2118/200280-ms","DOIUrl":"https://doi.org/10.2118/200280-ms","url":null,"abstract":"\u0000 The scope of this paper is to share technical knowledge and experience gained on the use of non-metallic materials in off-shore environments. The proposed applications lead to the highest benefit level in terms of maintenance interventions as well as to weaknesses jeopardizing the productivity.\u0000 In particular, we evaluated the use of:Glass-reinforced composite material in offshore platform boat landing and stairs, instead of galvanized grating;Glass-reinforced epoxy pipe for offshore firefighting network;Plastic reinforcement sleeve on the protection of tube bundle heat exchanger welding.\u0000 Analysis was carried out on obtained results. The approach took into consideration the technical results after long period of installation in a boat landing and firefighting network offshore with averse environmental conditions, while for the plastic sleeve it was a proactive action against failure and the relevant study of consequences in case of removal. Present paper is not an innovative implementation but it is born from the daily offshore plant observation with the particular aim to improve the asset integrity trying to guarantee the best performance, reducing maintenance and restoration cost.\u0000 Positive and negative results on the above applications will be mentioned to permit as final conclusion a proper material selection and design accuracy for future application.","PeriodicalId":10912,"journal":{"name":"Day 3 Wed, March 23, 2022","volume":"95 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75081594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Practical Solution for Rigless Water Shut off Without Using Thru- Tubing Bridge Plug in offshore Gas Lift Well, GUPCO - Egypt","authors":"M. Abdulmageed, Aly Elkordy, M. Vazquez","doi":"10.2118/200043-ms","DOIUrl":"https://doi.org/10.2118/200043-ms","url":null,"abstract":"\u0000 The Gulf of Suez Petroleum Company (GUPCO) is one of the main production Companies in Egypt. Most of production rate in GUPCO is dependent on gas lift method for lifting reservoir fluid to the surface. Many reservoirs in Gulf of Suez are depletion (solution gas drive); so GUPCO injects about 150,000 BWPD to compensate reservoir pressure, and GUPCO has several active water drive reservoirs which water increasing comes from bottom intervals in some cases. As the water cut increases in the well, water shut off (WSO) is required; based on production logging tool (PLT) data, to avoid water loading (backpressure on formation), allow low quality sand/ intervals to share in production, avoid corrosion of wellbore tubing, and scale build up in the tubing which may cost a lot of money for cleaning.\u0000 In general, GUPCO uses thru-tubing bridge plug (TTBP) and capping it with sufficient length of cement column for rigless WSO. As all fields of GUPCO are offshore; so WSO and other jobs are costly in comparison to onshore fields. Based on this, any cost saving, innovation, or idea lead to maximize output in safe manner (e.g. increasing well production oil) is highly appreciated and recommended for execution. Water shutoff techniques are either mechanical methods or chemical methods. These methods can be used individually or together in one job. Mechanical methods are usually used in wellbore WSO, and chemical methods are used in near wellbore (NWB) for plugging perm zones or restricting water flow as relative permeability modifier (RPM) chemical. Water shut off selection depends on many factors as well deviation, well completion type, and others that should be taken in consideration.\u0000 This paper details some of the challenges associated with performing conventional WSO using electric-line and how to overcome these challenges. For our interested case, there is no common thru-tubing bridge plug (TTBP) in the market can be set in 9 5/8\" and pass through minimum tubing restriction (XN- nipple 2.63\" ID). Therefore, the well was planned to perform WSO using CTU with high cost, which is low priority for the time being. The practical WSO method provides solution for these challenges with low cost, and high percentage of success.","PeriodicalId":10912,"journal":{"name":"Day 3 Wed, March 23, 2022","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77889746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Petrophysical Basis of Gas Transportation in Coal Reservoirs-Implications on Sorption and Diffusion","authors":"P. Naveen, K. Ojha","doi":"10.2118/200116-ms","DOIUrl":"https://doi.org/10.2118/200116-ms","url":null,"abstract":"Comprehensive and systematic analysis of complex pore networks is vital in elucidating the transportation of gas in coal reservoirs. In this study, multiscale heterogeneity of high volatile bituminous (hvBb) coal was reconstructed to replicate the pore connectivity. Furthermore, LPA-N2 data provides information about pore characteristics. With the digital and physical data, reliable pore-scale modelling was developed for the prediction of pore filling, sorption and diffusion of gases, including the network of pores and flow paths. The results obtained from this systematic approach is informative and gives complete details about the internal structure of coal that is viable for transportation of gas. Pore-scale modelling replicates familiar lab results. Consequently, geoscientists and reservoir engineers will be able to shorten traditional cycle times dramatically, better understand increasingly complex heterogeneous coal reservoirs, and evaluate exploratory wells, asses field development potential, and investigate early production strategies, as well improved recovery scenarios.","PeriodicalId":10912,"journal":{"name":"Day 3 Wed, March 23, 2022","volume":"26 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78230785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Designing an Optimum Recipe for SP Flooding in Harsh Carbonate Reservoir Conditions High Temperature High Salinity","authors":"M. Ahmed, A. Sultan, A. AlSofi, H. Al-Hashim","doi":"10.2118/200246-ms","DOIUrl":"https://doi.org/10.2118/200246-ms","url":null,"abstract":"\u0000 Chemical-Enhanced-Oil-Recovery (CEOR) processes have been used for increasing oil recoveries from oil reservoirs following the primary recovery phase. At harsh reservoir conditions (high salinity and high temperature), many CEOR methods fail to achieve their objectives. This raises the challenge to design optimum recipes that tolerate these harsh conditions and hence attain maximum hydrocarbon recovery at the minimum possible cost.\u0000 This paper evaluates the effectiveness of a Thermo-Viscosifying Polymer (TVP) and an Acrylamido Tertiary Butyl Sulfonate (ATBS)/acrylamide (AM) copolymer in mobilizing residual oil from carbonate. The surfactants are carboxybetaine based amphoteric surfactants SS-880 and SS-885. These candidates were selected based on an intensive evaluation process carried out in previous works at KFUPM, which includes fluid rheology, long-term thermal stability, interfacial tension (IFT), adsorption and microfluidic studies. Furthermore, contact angles were measured at high pressure and high temperature using a captive drop analyzer. Slug size and injection sequence optimization were also investigated through core-flooding experiments. Different injection scenarios including SW-SP-SW, SW-P-S-SW, SW-S-SW-P-SW and SW-P-SW-S-SW were also investigated to identify the best injection scenario. The coreflooding experiments were conducted at 90°C. The seawater (SW) used in this study is Arabian Gulf seawater having salinity of 57,000 ppm.\u0000 The results showed that surfactant-polymer combination and SW-SP-SW injection scenario were the best in terms of oil recovery. The optimum chemical combination was found to be carboxybetaine (0.05% wt.) and ATBS/AM (0.25% wt.). It was also observed that the recoveries were increasing proportionally to the slug-size. This indicates that the chemical injection sequence and slug-size have a significant impact on ultimate oil recovery. This is believed to be due to the advantageous synergies between the chemicals. The core-flooding experiments confirmed the importance of optimizing the design of CEOR processes taking into consideration the type of chemicals, concentrations, slug sizes, and flooding sequence of the different combination of seawater (SW), surfactant (5) and polymer (P).","PeriodicalId":10912,"journal":{"name":"Day 3 Wed, March 23, 2022","volume":"68 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82389680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Successful Implementation of FAL in PDO Gas Wells","authors":"Faisal AlYhayaai, C. Veeken, Mohammed Razvi, Kusela Ardia, Thabit AlDaraai, AlMuntaser AlKindi","doi":"10.2118/200064-ms","DOIUrl":"https://doi.org/10.2118/200064-ms","url":null,"abstract":"\u0000 Saih Nihayda (SN) cluster is one of Petroleum Development Oman (PDO) gas assets that contributes by ∼25% out of the overall PDO gas asset's production. SN Deep is one of the biggest SN cluster fields, which was brought on stream since 2006 and started seeing water breakthrough and liquid loading as some of the late field life challenges. This paper provides an overview of successful application of foam-assisted lift (FAL) for deliquification in some wells in SN Deep field that suffered from water production where their production & uptime were heavily impacted. This paper sheds light on the challenges associated with the successful implementation of FAL in SN Deep.","PeriodicalId":10912,"journal":{"name":"Day 3 Wed, March 23, 2022","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88478143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First Application in Oman of New Single Stage Retarded Sandstone Matrix Acidizing","authors":"Hajir Qassabi, A. Rafliansyah, Johnny Falla, Ahmed Al-Yaaribi","doi":"10.2118/200297-ms","DOIUrl":"https://doi.org/10.2118/200297-ms","url":null,"abstract":"\u0000 The objective of matrix acidizing in sandstone reservoirs using acid systems that contains Hydrofluoric acid (HF) is to widen the pore throats and spaces in order to increase the permeability around the wellbore and also to remove formation damage. One of the major disadvantages of this acid system is the secondary and tertiary reactions, which may end up with precipitations that damage the formation. Because of this, pumping sufficient pre- flush and post-flush volumes of Hydrochloric acid (HCl) is critical to prevent such damaging reactions. However, the placement of such fluids still are a concern in multiple opened layers or long open intervals zones.\u0000 Stimulating sandstone reservoirs in the Southern fields of the Sultanate of Oman is very challenging, especially in those that exhibit relatively low permeability. These formations, based on petrology work, contains significant amount of clays and feldspars, which make it difficult in the designing process of the acid formulation. A new version of HF acid system was recently developed. It is specially formulated, so it does not require the addition of Hydrochloric acid (HCl) pre-flush. Because of this, it can be pumped as a single stage system. In addition, its higher reactivity allows deeper penetration and it has the ability to minimize secondary reactions and damaging precipitates.\u0000 Lab testing work was conducted to ensure the effectiveness of this single stage acid system. The results were promising as they show a good improvement in the rock permeability. These results were encouraging to carry field trials in the sandstone reservoirs in Oman Southern fields. Up to now, it has been pumped in these type of sandstones for oil producer wells and for water injector wells. The actual treatment using this system showed increased oil productivity by higher than 60% and higher than 80% in water injectivity.\u0000 This paper presents the testing, designing and pumping of the single stage acid system, as well as the comparison with the conventional HF acid system in Southern fields of Oman. It outlines the laboratory work and analysis done as well as the field trials.","PeriodicalId":10912,"journal":{"name":"Day 3 Wed, March 23, 2022","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81265459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feasibility of Ion-Modified Water for Low Salinity Water Flooding: A Case Study for Ultra-High-Salinity Carbonate Reservoir in Akanskoe Oilfield Tatarstan, Russia","authors":"M. Varfolomeev, Mojtaba Rezaei Koochi, C. Yuan, R. Khayrtdinov, A. Mustafin, M. Glukhov, R. Kadyrov, V. Sudakov, S. Usmanov","doi":"10.2118/200046-ms","DOIUrl":"https://doi.org/10.2118/200046-ms","url":null,"abstract":"\u0000 This paper presents the feasibility of the application of ion-modified water for enhanced oil recovery (EOR) in low permeable carbonate reservoir with ultra-high salinity of more than 220000 mg/L. Influence of different ions on wettability alteration, interfacial tension (IFT), scale tendency, recovery factor, and water injectivity was investigated. For choosing the optimized injection-water sequence, different types of water (formation water, distilled water, fresh water, and ion-modified water) were used. First, their effects on wettability alteration by measuring contact angle (oil-water-rock) and IFT were evaluated. Then, core flooding experiments were carried out to investigate how different injection sequence affects the oil recovery and injectivity. Furthermore, the scale tendency of different salts was simulated. The results showed that Mg2+ is the most effective ion. The addition of Mg2+ can fast change the oil-wet (130°) carbonate rock to water-wet (29°). The presence of mono-valent ions has negative effects on the effectiveness of Mg2+ on wettability alteration. Also, the presence of Mg2+ in fresh water and distilled water can reduce oil-water IFT two times lower. Core flooding experiments showed that after fresh water or formation water flooding (until 100% water cut), the sequent diluted formation water (diluted 10 times) yielded incremental oil recovery of about 3-5%, while the Mg2+ modified water obtained incremental oil recovery of about 8-18%. This indicates that Mg2+ modified water has a promising prospect in EOR in carbonate reservoirs.\u0000 A comprehensive analysis combining contact angle measurements, IFT testing, and core flooding experiments indicates that the high efficiency of Mg2+ modified fresh water for EOR mainly benefits from its strong wettability alteration ability. In addition, it was found that the existence of Mg2+ and SO42− can reduce the tendency of precipitation of salts compared with using only fresh water or diluted formation water. This work proves that ion-modified water by adding Mg2+ to fresh water can be an effective, low cost and environment-friendly EOR method for low-permeability carbonate reservoirs with ultra-high salinity. Simultaneously, this research provides some basic data that can help to enrich the theory for developing low salinity water flooding for EOR.","PeriodicalId":10912,"journal":{"name":"Day 3 Wed, March 23, 2022","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84667881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}