bluuebunny/crossref_metadata_2025 huggingface dataset:
Green Screen Application Digitalized Approach for the Environmental Management System (EMS)
Authors: Abubakr Ahmed Abdulraheem , AlGhamdi Abdullah Omar
Published: October 2022

As part of a comprehensive investigation, this study has reviewed the companies adopting digital technologies to establish an ISO 14001 Environmental Management System (EMS). Organizations have implemented digital strategies for environmental management systems (EMS) to ensure that environmental elements are continually improved. Green Screen is a real-time Business Intelligence (BI) dashboard designed to digitalize the Environmental Management System (EMS) providing a holistic overview of the department's Environmental performance and coming to an alignment with the global trend to deploy IR 4.0 technologies to digitalize operations. The solution provides real-time information on the Environmental Management System (EMS) significant aspects that consists of Climate, Water, Land, and Decarbonization.

The dashboard is meant to aggregate data from multiple sources connected to the organization's Environmental Aspects, evaluate it according to the defined KPI formula, and then show the needed information in a user-friendly dashboard to provide insights into the organization's performance. The Green Screen dashboard uses many tools to collect, analyze, and present data relating to the department's environmental aspects. The system was carefully designed to boost the overall department Environmental Management System (EMS) by providing critical insights, such as KPI exceeding and emissions offsetting, to all stakeholders and customers. These insights are grouped based on the organization's EMS. The Green Screen will positively impact the overall environmental performance by the following: Achieving the full implantation in EMSEliminating around 24 working hours per month needed for monitoring.Providing the stakeholders and customers with an easy interactive monitoring toolDriving proper corrective actions and adjustment to under-performing areasServing as an online, easy, and fast access reference to all the department's EMS

The report also discusses the factors that influence the acceptance of environmental certifications by organizations, particularly in developing nations.
Digital Twin Application for Boosting Oil Production, Predictive Analytics of Asset Integrity and Mid-Term Forecasting of Field Performance
Authors: Vorobev Ilya , Koshkin Timur , Prokopev Mikhail , Rakhmangulov Yulay , Kombarov Semyon
Published: October 2022

There are often situations when readings of a large number of sensors installed at the field are used as needed, rather than on a systematic basis. The paper is devoted to the experience of building and using a Digital twin (DT) of the oilfield, history matched using instrument readings at the main nodal points from the well bottom to the tank farm. Digital twin is used to solve practical problems of selecting measures to increase production, specifying the maintenance program and chemical injections, overall allocating production by wells without direct measurements of production flow and forecasting in different time horizons the entire field production.
Enhanced Oil Recovery at Zero Cost. Will Cyclic Waterflooding Breath a New Life into Mature Oil Fields? A Case Study in South Kazakhstan
Authors: Mukanov Adil , Kudalsha Aimurat , Kassenov Duman
Published: October 2022

South Kazakhstan is one of the hydrocarbon rich provinces in Kazakhstan, which is among the top 20 oil producing nations. However, most of the big fields of the basin are entering the last stages of development. Consequently, operators look for opportunities to maintain economical production by applying IOR methods at lower costs. Hence, cyclic waterflooding was considered a good candidate because of no expenditures. The paper demonstrates the main stages, mechanisms, and results of the project.

The schematic of cyclic waterflooding is carried out by changing injection rates in phases. This leads to fluid flows redistribution in heterogeneous reservoirs due to capillary forces. So, the field trial was implemented on the KK field, which is represented by stratified sandstone mostly waterflooded. The injection pattern is irregular and eight patterns participated in the project. Rates varied from 50 t/d up to 300 t/d. Phases consisted of one group of injectors introducing water at lower and another group at higher rates with one-month duration. After that, the wells’ rates were adjusted.

Cyclic waterflooding has been in operation for almost a year. During that period, producers’ working modes haven't been changed. As the result of observations, some wells have moderate or even no impact, but some wells exhibited remarkable improvements, e.g. a producer which has three injection wells around experienced watercut decrease from 90% up to 40%, while oil rate increase from 1 t/d up to 5 t/d. Overall, oil production from a group of nearby producers whose oil rates were previously reducing with a 41% decline has a clear trend of full stabilization. The main aspect causing this phenomenon is watercut decrease. The parameter fell from 95% to nearly 86%. Thus, it became beneficial not only in terms of oil production but also surface infrastructure. Less water volume treatment is required and it is critical for gathering system under conditions of growing water production.

Summing up all the above-mentioned cyclic waterflooding has big success in our field case study. The initial modest forecast turned to significant oil increment and watercut decrease. Moreover, the company saved money which makes this IOR approach the most preferable to implement. Therefore, additional two projects recently started on other similar fields. It is obvious that if properly managed, improved oil recovery is possible at no cost breathing new life into old fields.
Predictive Analytics for Third Party Threat and Geohazard
Authors: Ahmad M Nazri , Ali Napiah M Nazmi M , Koi Swee Ling , Idris Naila Rusma
Published: October 2022

Third party encroachment and geotechnical hazard are two major threats for onshore pipeline system and managing them is a real challenge to pipeline operators including PETRONAS. If these threats are not properly managed, the consequences may lead to major catastrophe which impacts public safety, asset damage, financial loss and tarnish company's reputation.

Aerial surveillance i.e. drone or helicopter has been widely used by pipeline operators for inspection and monitoring of 3rd party threat and geotechnical hazard. However, the data produced from these inspections are in the forms of images and videos resulting to massive datasets. Manual interpretation of these data has caused lengthy processes, time consuming, costly, and prone to human error during data analysis. Motivated from the above pain points, a predictive analytics tool was developed in-house using various machine learning technologies to automate anomalies identification captured during aerial inspection as part of monitoring and risk management along pipeline right-of-way (ROW). The outcome from the predictive analytic tool has assisted pipeline operator to perform early intervention of possible pipeline failure due to third party and geohazards. Data automation has significanly reduced data processing time and human error for anomalies detection and verification, this subsequently improve workforce productivity while reducing safety risks, operations and maintenance costs.
Selective and Reversible Water Shut-Off Agent Based on Emulsion System with Nanoparticles Suitable for Carbonate Reservoirs at High Temperature and High Salinity Condition
Authors: Abe Masashi , Furuno Jumpei , Murakami Satoru , Sonoda Takashi , Sergeev Vitaly , Tange Masaaki , Hiraiwa Takeshi , Yonebayashi Hideharu
Published: October 2022

This paper presents the evaluation results of water shut-off (WSO) agent based on emulsion type chemical material with nanoparticles. The WSO agent called Emulsion System with Nanoparticles (ESN), it has several unique advantages to existing polymer and gel materials; high thermal stability, low sensitivity to mineralization, thixotropic characteristic, selectivity of blocking effects for oil and water, and reversibility of blocking effect. In WSO application, these properties of ESN could be a good match for the tasks of improved oil recovery. Also, the surface modified silica (SiO2) nanoparticles have an important role to drastically enhance stability of the emulsion system. The ESN can be prepared easily by mixing emulsifier and silica nanoparticles with the on-site oilfield materials such as crude oil and brine. The refined diesel oil can be used for ESN preparation instead of crude oil, so it will be an option depending on the situation of target oil field infrastructure and operator's policy. To evaluate the performance of ESN as WSO agent for UAE's carbonate reservoirs, core flooding tests using low permeability carbonate cores with different water saturation were performed at high temperature condition. The ESN, which is confirmed to be stable at 120 °C and 240,000 ppm TDS, achieved 85 % permeablity reductions for intermeaiete and high Swi cases of the core flood tests. The relative permeability analysis confirmed unblocking by oil inflow for intermediate and low Swi cases. Through comparative analysis and discussing these test results, the laboratory study investigated technological potentials of ESN to block water zones and control water cut of oil wells. This paper introduces the detailed evaluation results of ESN and possibility to successfully apply it for UAE's oil fields in the future.
Multilateral Fishbone Wells Utilization to Unlock the Production Potential and Analyze the Interference Phenomena of Marginal Field with Depletion Drive Mechanism
Authors: Magomadov Ismail , Balhasan Saad Abdallah , Elsayed Mohamed , Abbas Hafsat Abdullahi
Published: October 2022

Technical and economic optimization of marginal mature fields currently becomes a major industry concern: such fields contain considerable amounts of hydrocarbon reserves that could be produced using current technology simplifying lack of pressure support and interference phenomena issues. The total oil recovery factor of depletion drive reservoirs varies from 5 to 30%. This type of reservoir does not initially have a source to maintain pressure: energy is mainly supplied by the release of dissolved gas due to the rapid continuous decrease in pressure and the low compressibility of fluids. Multilateral wells technology accomplished with ESPs is used in our study to mitigate the interference phenomena and provide the strong pressure support to the system- a theoretical marginal reservoir. The major objectives of this work are to design various multilateral alternatives, analyze technical standards and specifications, observe production performance, and judge the designs technically, economically, and based on ethical and environmental codes compliance. Design alternatives of this study contain 2, 4 or 6 fishbone type laterals under 45 or 90 degrees inclination angles. The main horizontal bore is fully cased and cemented, and the branches are fully cased and perforated. All alternatives were accomplished with Electrical Submersible Pumps (ESP) technology. Based on technical performance (Recovery Factors and Cumulative oil production) one design alternative was selected as the best one (2 laterals from 45 degrees group): RF was enhanced from initial 2.6 to 22.6 %. Based on the results of economic evaluation and risk analysis, alternative with dual 2 laterals under 45 degrees inclination demonstrated the best performance. Production performance of marginal field was optimized increasing the RF from primary recovery 2.55 % to 22.63 % after utilization of multilateral well technology combined with ESP-s.
Digitalization of Corrosion Management – Use Cases for Oil and Gas 4.0
Authors: Sharma Prafull , Oskuie Aliakbar , Ennaceur Chiraz , Silatani Mehrdad
Published: October 2022

This paper describes the applications of digitalization technologies specifically Industrial Internet of Things (IIOT) to predictive Corrosion Management with an attractive use case of corrosion under insulation. The available technologies and case studies of field use cases will be presented.

Hidden corrosion such as corrosion under insulation (CUI) can be better managed with digital data harvesting and with predictive tools using data of the assets such as knowledge of moisture locations and temperature etc. This method involves use of this data set to manage the assets holistically, prioritizing the risky locations and scheduling their inspection and maintenance. A predictive method is described which can help the asset owners not only manage the assets in a cost-effective way but in a safer way too if the risks are pre-identified and acted upon.

In this article the predictive CUI monitoring technology is introduced. The technology includes sensing conditions under the insulation and predictive modeling to estimate risks in a very rapid manner. In this paper, use-cases and applications will be explained and shown.

The new method of using sensing and industrial IOT to detect and predict corrosion in the field will be a huge impact for the asset integrity struggling with the threat of hidden corrosion such as corrosion under insulation. The paper will reveal the latest case studies from the field usage of monitoring thereby building confidence in it and advancing the knowledge base in corrosion industry.
Dynamic Optimization of Demulsifier Injection and Water Separation Crude Oil Through Data Analytics
Authors: White Ramsey James , Lopez Andreu Miguel Angel , Alhamoud Abdullah Abdulrahman
Published: October 2022

This paper describes a sophisticated control method (known as "Smart Demulsifier Control") for automatic adjustment of optimum demulsifier chemical injection, which was adopted at several Gas Oil Separation Plants in Saudi Aramco. Demulsifier chemical is a key additive used for oil and water separation. Excessive dosing would lead to increased operational costs while demulsifier under-dosing will impact crude quality due to separation upsets such as desalter grid overload. The system utilizes models that were developed using data analytical tools to optimize demulsifier chemical injection in real time.

In a Gas Oil Separation Plant, formation water is first separated in a horizontal three phase separator. The rest of water is removed in electrostatic coalescers to achieve the required crude specification. The amount of demulsifier added can balance the separation within certain limits. There are several operational parameters that affect the separation. Most are not controlled (disturbances) such as crude type, emulsion tightness and temperature. The method uses basic instrumentation measurements to measure the online separation balance, compares the actual data to expected data based on a process model and adjusts demulsifier concentration within an adequate dynamic window using a combination of PID algorithm control loops.

The implementation of Smart Demulsifier Control scheme at several GOSPs was proven to be a reliable and robust method to fully automate the addition of this important chemical. The online separation measurement provides a clear visualization of the overall separation balance and it is used to adjust dosages accordingly with PID loops. PID algorithm can be easily adjusted at each plant to ensure the speed of response is adequate. Usual plant disturbances that can affect separation balance such as well alignment changes, feed rate and water cut variations are tackled by the control scheme through live separation monitoring. Operators can also influence the separation with some margin parameters provided in the scheme. The dynamic operating window ensures that the amount of demulsifier is within reasonable limits at all times. The design is parametrized to allow for easy modifications in case of new crude feeds, demulsifier effectiveness formula changes or seasonal changes (summer/winter). This novel scheme has been implemented at nine Gas Oil Separation plants processing Arab Light crude. Based on a complete year of evaluation, a very significant reduction in electrostatic coalescer upsets related to inadequate water separation in the three-phase separator has been achieved along with an average reduction of demulsifier consumption of 15%.

A patent for the control scheme has been granted by the United States Patent and Trademark Office. It is unique in its simple approach to optimizing demulsifier dosage while ensuring a smooth process of crude oil emulsion treatment and separation.
Detection and Monitoring of Corrosive Oilfield Microorganisms via Novel Biomarker Technologies
Authors: Lahme Sven , Mand Jaspreet , Oparaodu Kingsley , Enning Dennis
Published: October 2022

Petroleum-transporting infrastructure can experience severe corrosion in the presence of microbial biofilms, a process termed microbially-influenced corrosion (MIC). However, not all microorganisms are corrosive and distinguishing corrosive from benign biofilms remains challenging with current technologies. In recent laboratory tests we identified two biomarkers suitable to discriminate corrosive methanogenic archaea (micH) and sulfate-reducing bacteria (micC) from their noncorrosive counterparts. In this study, we demonstrate suitability of newly developed qPCR assays, that target the specific microbial enzymes micH and micC, for field application.

Water samples and pig debris were obtained from various oil-transporting pipelines that with high likelihood experienced MIC at the time of sampling as well as from pipelines without a perceived threat of MIC. Samples were analyzed with existing methods including 16S rRNA gene sequencing to identify the whole microbial community present in the samples and qPCR assays designed to enumerate total bacterial and archaeal populations. These results were compared to those obtained from the use of newly developed targeted qPCR assays for micH and micC.

First we tested the novel assays on pig debris samples obtained from a North American pipeline in which active corrosion was suspected from recent in-line inspection (ILI) date. The results showed 5.6·104 gene copies of micH and 7.9·104 gene copies of micC per g of pig debris. In comparison, the micH and micC biomarker were not detected in a pipeline from the same field that did not show active corrosion. Subsequently, we tested the novel biomarker assays on more readily available produced water collected from an African oilfield. On average, 2.4·102 gene copies of micH/ml were measured in MIC-affected pipelines. The MIC biomarker micC, on the other hand, was detected at about 1.2·102 gene copies/ml in only one of the tested pipelines that experienced MIC. Intriguingly, neither micH nor micC were detected in wellhead fluids or other areas where MIC was not suspected. The correlation of micH and micC with active corrosion in oil field settings demonstrated the merit of these novel biomarker to serve as indicators of active MIC. Detection of the MIC biomarkers in water samples from affected pipelines would also allow efficient microbial monitoring independent of biofilm samples. This would allow easier implementation of this new biomarker technologies in the field. Furthermore, the detection of both biomarkers in samples from geographically distinct oil field operations points to global significance of these assays.

MIC is notoriously difficult to detect and monitor with current technologies. The development of these novel MIC biomarker technologies enables, for the first time, the targeted detection of highly corrosive microbial communities to develop truly diagnostic and actionable data for MIC detection and mitigation.
A Study on Reliability-Based Assessment of Ageing Fixed Offshore Platforms Located in the Arabian Gulf
Authors: Thomas Abin Pulivelil , Nekstad Ole Jan
Published: October 2022

Offshore platforms and tubular structures are examples of lightweight supporting structures for oil and gas and wind energy production units. However, their reduced weight is obtained at the expense of increased susceptibility to fatigue failure because of their tubular welded joints or connections. Hence extra consideration must be given to the fatigue design of the hot spots. The objective of the proposed shell fatigue design methodology for critical jacket joints is to calibrate the fatigue reliability for inspection planning studies. This study summarises research on the development and use of reliability-based jacket joints inspection planning approaches for offshore structures. The main objective of the study is to reduce the uncertainty introduced by SCF calculations on crucial joints by modelling such joints as an FEM shell model. The study also provides an application process and workflow for a standard Arabian Gulf jacket for fatigue reliability assessment. First Order Reliability Method (FORM) is used to determine the reliability index. The study also provides insights into methods for planning in-service inspections of ageing offshore platforms.
Erosion Prediction in FCC Unit of Refinery Through Computational Fluid Dynamics Simulation
Authors: Abdul Quiyoom , Rakshit Pranab Kumar , Voolapalli Ravi Kumar , George Prince , VN Dileep Kumar , Thota Raviteja
Published: October 2022

In the Fluid Catalytic Cracking unit of refinery, erosion due to catalyst impact on wall refractories is a serious issue that affects the plant performance. In the present study, Computational Fluid Dynamics (CFD) coupled with Discrete Element Model (DEM) method is used to characterize gas-solid flow dynamics and erosion in regenerated catalyst slide pipe (RCSP). Catalyst particles size in the range of 1-180 µm were considered for the simulations. The predicted erosion profile was verified by comparing with thermography experiments and were found in a good agreement.

The predicted results revealed that due to partial opening and orientation of regenerated catalyst slide valve, the rapid alterations of flow direction of catalyst particles take place. Particles recirculate in the rear end of the pipe and continuously impinges at the 12 o'clock position upstream of the valve. This led to erosion in the pipe. The experimentally validated CFD model was used to characterize the erosion profile under different relative openings of regenerated catalyst slide valve (RSCV). It was observed that with increasing the valve opening the erosion profile was reduced due to decreases catalyst recirculation velocity and vice-versa. Further, effect of valve opening orientation was also studied and it was found that by changing the valve opening orientation from parallel to ground surface to down towards, erosion was not observed due to small recirculatory flow of catalyst with low velocity. The results presented in this work will help refiners to understand the catalyst flow dynamics inside the regenerated catalyst slide pipe, root cause of erosion in pipes, and to achieve further improvements in the performance of plant.
Impact of Diagenesis on the Reservoir Properties of the Cretaceous Kharaib Formation, Sajaa Field, Sharjah, United Arab Emirates
Authors: Phukan Madhujya L , Siddiqi Saad A , Almunaifi Asma , Robert Matthew J
Published: October 2022

The Early Cretaceous Kharaib Formation is one of the most prolific hydrocarbon bearing reservoirs in the Middle East. Based on sedimentary characteristics, the Kharaib Formation is divided into three main intervals/zones: the lower, middle and upper Kharaib. Interpretation of the depositional fabrics and prediction of reservoir parameters is often difficult due to the Kharaib Formation's diverse array of sedimentary characteristics. To address the considerable heterogeneity of the Kharaib Formation, this study investigates depositional characteristics and the diagenetic impact on reservoir quality within the Sajaa Field.

The Kharaib Formation sediments were characterized using a Dunham/Embry & Klovan (1971) defined classification scheme. Analytical techniques via thin section analysis, scanning electron microscopy (SEM) and capillary pressure data were used to qualitatively and semi-quantitatively assess porosity and the diagenetic processes involved in its evolution. Key reservoir quality parameters for Kharaib intervals were defined by combining petrographic analysis and conventional core methods.

The sedimentological characterization of the Kharaib sediments in the Sajaa Field showed a range of Orbitolina-bearing carbonate textures, which were interpreted as inner-ramp deposits. The stacking pattern of the depositional facies showed intermediate-order trends. The conventional core analysis measurements showed poor to good reservoir properties with porosity values of 0.7 – 23.2% and permeability values from negligible to 2 – 3 md. The pore system is dominated by grains and matrix-hosted micropores, which are primarily generated via diagenesis. Qualitative thin section analysis identified grain-hosted micropores as the most significant microporosity type, highlighting that grain-rich textures are relatively more porous compared to mud-rich textures.

Diagenesis transformed both the matrix and various grain types (e.g., micritized grains, foraminifera etc.), generating considerable micropore volume. High resolution SEM imaging, along with semi-quantitative assessment, highlighted that diagenetic modification of the micritic sediments led to an abundance of sub-rounded to polyhedral crystals exhibiting primarily sub-punctic to punctic intercrystalline contacts that generated a porous fabric. Mercury injected capillary pressure (MICP) data, confirmed the abundance of micropores within the pore size distributions of studied samples.

This study demonstrates the importance of considering textural variation within the Kharaib Formation when assessing the reservoir coupled with the fractured nature of the unit. The established microporosity-depositional relationships when combined with the updated core descriptions now allow for the integration of textural trend information in the field that can be applied to refine reservoir property and abundance distributions.
Proactive Management of H2S Levels in a Mildly Sour Gas Field Through Production System Optimization: Case Study From Central Luconia Province, Malaysia
Authors: Mohd Ali Haneff , Omar Siti Ili Fatimah , Langat Adrian , Mohamad Shah Samsul
Published: October 2022

High H2S issue was investigated in Field B shortly after production, with quite a variation on the measured H2S readings. The initial opinion was it might be related to the measuring methodology, as no evidence to suggest that the H2S level would increase over time from the reservoir point of view. To verify this, a full sampling program was conducted, consisting of onsite sampling and laboratory analysis. This includes stain tubes measurement, online gas chromatograph, H2S analyzer and UOP method. The H2S isotope analysis was also conducted to determine the H2S source and its future behavior in the reservoir. This paper serves as lesson learnt and best practices in H2S management from subsurface to facilities unified approach, highlighting the importance of proper data acquisition, with focus on contaminants. Indeed, H2S is a contaminant found widely in oil and gas industry and can be a limiting factor to development or hinder production if it is not appropriately characterized during exploration, appraisal and early stage of production.
Addressing the Challenges of Simulating EOR and CO2 Storage Projects at Reservoir Scale: Accurate Estimation of Trapped Gas Saturation
Authors: Aghabozorgi Shokoufeh , Sohrabi Mehran
Published: October 2022

One of the first and foremost steps in the feasibility analysis and site selection of geological CO2 storage projects is estimating the storage capacity of the appointed aquifer or depleted reservoir. It has been established that the volume of CO2 stored due to capillary trapping is significantly higher than other active mechanisms. Therefore, an accurate method is required to determine the trapped gas saturation in the system. This method is also of significant importance for simulating any other process involving cyclic injection of fluids in subsurface reservoirs as the hysteresis in relative permeability is a direct function of trapped gas saturation. Examples of the cyclic process in subsurface reservoir engineering are gas storage projects and reservoirs undergoing Enhanced Oil Recovery (EOR) injections. In this study, we present a detailed study of the reservoir scale simulation results using commercial software, and we discuss the challenges observed in calculating the trapped gas saturation.

The first challenge is that Land's formulation relates the initial and residual non-wetting saturations measured during an imbibition cycle. However, in many reservoir blocks, the volume and rate of displacing fluid are insufficient to ensure reaching the residual values. Accurate determination of saturation histories in various reservoir grid blocks is also challenging as small oscillations make it hard to identify the flow reversal points. A significant amount of error is introduced in compositional simulations when the composition of trapped gas saturation enters mass transfer calculations, and the trapped gas is dissolved again in the oil phase. Whereas physically, it should be isolated and shielded by the water phase. Finally, an inaccurate definition of saturation-dependent functions can increase the error associated with calculating relative permeability data using trapped gas saturation.

In this study, we present a new workflow for calculating the trapped gas saturation, addressing all the abovementioned issues. The backbone of this workflow is an efficient algorithm which removes any oscillation misidentified as a flow reversal point. The results discussed in this paper indicate that the available formulation in the literature should be deployed carefully (considering the active mechanism in the system) to decrease the uncertainties. As a result, the feasibility of EOR methods, the site selection for CO2 storage projects and the decision-making process can be based on more reliable data.
The Accurate and Efficient Simulation of a Fractured Tight Gas Condensate Reservoir Using Embedded Discrete Fracture Model
Authors: Yuan Chengwu , Yu Wei , Ghanbarzadeh Soheil , Liu Chuxi , Miao Jijun
Published: October 2022

The hydraulic fracture modeling is critical for the well dynamic performance and development optimization in the fractured condensate reservoir. The conventional approach based on LGR (Local Grid Refinement) is widely used but with low computational efficiency, and sometimes with artificial fracture orientation and geometry. In this study, a new workflow to model the hydraulic fractures using EDFM (Embedded Discrete Fracture Model) is developed to couple with the Nexus reservoir simulator for the first time. Borrowed from the dual continuum concept, the main idea of EDFM is the non-intrusive embedding of the fracture medium physical properties (such as transmissibility, pore volumes, etc.) into the pre-existing matrix cell blocks. Using the EDFM, tedious work such as model re-gridding and refinements can be avoided, and realistic fracture geometry and geological structures can be honored with only a fraction of the total computational cost.

We validate the EDFM approach firstly with a simple mechanistic model and then a sector model with 18 hydraulic fractures in Cartesian grids. The results from the traditional LGR method are compared with those from EDFM to demonstrate its robustness. For the same fracture geometry and reservoir model configurations, the LGR-based and EDFM-based approach gives almost identical results for production simulations. We then applied this workflow to a more realistic sector model with 18 vertical wells in a tight gas condensate reservoir with corner points geometry. We demonstrated that the EDFM approach enables more realistic hydraulic fracture modeling, including the flexibility to incorporate geomechanics-consistent fracture orientation, gridding-independent fracture height, fracture half-length, and straight-forward modifications of fracture properties. Additionally, the speed of the EDFM is much superior to the LGR-based one. The speed-up factor reaches about 50 when appropriately decomposing the domain in this sector model, reducing the computational time from about 8 hours to about 9 minutes. This EDFM-Nexus workflow enables a much faster and more robust fracture modeling, model calibration, development optimization, and business decision-making in the tight gas condensate reservoirs.
Evaluation of Simultaneous Injection Concept and Other Water Based EOR Strategies for a Carbonate Reservoir in North of the Sultanate of Oman
Authors: Kathel Prateek , Rawahi Zainab , Wunnik Johannes van , Groenenboom Jeroen , Harris Rob , Al Sulaimani Hanaa , Al Mjeni Rifaat , Dhahli Adnan , Balushi Abdul Aziz , Shukri Ibrahim
Published: October 2022

In this study development options are evaluated for a low permeability carbonate field located in the North of the Sultanate of Oman which has been on production since 1969. The dominant recovery mechanism is bottom aquifer water injection with an estimated recovery factor of around 50% till date. This study is aimed at testing the simultaneous injection concept and other water based EOR strategies for the field to present a range of options for future development. During the work several concepts were also designed to understand the impact of major heterogeneities on proposed recovery mechanisms, and to understand the role of gravitational forces on remaining oil distribution.

Major findings of this work include the development of a range of recovery options for the field with incremental recovery ranging from 2% to 20% (Recovery Factor), improved understanding of the impact of heterogeneities and the role played by gravitational forces. The application of "Experimental Design" of simulation runs ensured capturing of the range of uncertainties in heterogeneities and provided a distribution of outcomes. Economics was evaluated for surfactant polymer flood and simultaneous injection concept to facilitate decision making.
Historical Polymer Flood Oil Gain through Outstanding Subsurface and Surface Integrated Operations
Authors: Sawafi Marwan , Kindi Osama , Hashimi Abdulaziz , Ghailani Taher , Maskari Azza , Abri Moh’d , Hinai Suleiman
Published: October 2022

The largest polymer flood field in the Middle East is operating since 2010 with more than 40 polymer patterns and around 300 wells. Following a very diligent and complex operational procedures is essential to deliver the polymer properly to the reservoir. Throughout the past 12 years, this project went through several challenges such as injection uptime sustainability, polymer viscosity stability & polymer pumps uptime which have a direct ramification of the field polymer oil gain recovery.

In 2022, the field realized the highest polymer oil gain since the project commenced, around 50% improvement in the oil daily rate compared to the past three years. These substantial results are consequences of several initiatives such as Polymer viscosity improvements due to better monitoring and improvements on troubleshooting reaction time, sustainable injection uptime with more than 85% though better maintenance & monitoring of the polymer pumps and PSUs and Polymer injection optimization: increasing polymer consumption in good performing patterns and reduce/stop in the lower ones. All these initiatives have led to significant improvements in the polymer utilization factor by around 40%. It is crucial to sustain a good performance and stable operation & injection uptime prior to the polymer phase 3 start-up where more than 400 infill wells are planned to be drilled to expedite the polymer recovery without polymer facility expansion.

The objective of this paper is to shed light on the road map followed to restore value to this great project but also to provide insights to the newly introduced best practices that were developed by Marmul team and can be translated universally to any future polymer/cEOR project.
Thermal Aspects for Chemical EOR Projects Implementation
Authors: Osipov Andrey Valerievich , Bondar Mikhail Yurievich , Groman Andrey Andreevich , Chebysheva Olga Vadimovna , Milchakov Sergei Vasilievich , Kosikhin Anatoliy Sergeevich
Published: October 2022

Chemical methods of enhanced oil recovery in general and SP flooding, in particular, are considered as a promising tertiary method of developing mature oil fields in Western Siberia, with the potential to increase oil recovery to 60-70% of the initial geological reserves [1–3]. The selection of an effective mixture of surfactants and polymer for SP flooding is a complex and multi-stage process. Usually, the choice of chemical composition and modeling on the hydrodynamic model is carried out under isothermal condition at reservoir temperature [4,5,6]. However, recently some authors have been paying attention to the temperature aspects of SP flooding [7]. According to these studies, the change in reservoir temperature as a result of long-term injection of unheated water can play a decisive role in the choice of chemical composition and hydrodynamic simulate of SP flooding. This happens, firstly, due to the fact that the temperature significantly affects the IFT, on which the oil displacement coefficient of the SP composition depends. Secondly, the viscosity of the polymer solution and, consequently, the sweeping efficiency during SP flooding depends on the temperature.

In this paper, the temperature profile was evaluated in the area of the SP flooding pilot site, where flooding with unheated water was carried out for 12 years. Initially, the downhole temperature in the injection well was calculated based on analytical functions, which was then confirmed by field studies. As it turned out, the downhole temperature in the injection well is 42 °C, which is 45 °C less than the initial reservoir temperature.

At the second stage, with the help of analytical functions and hydrodynamic simulation, the temperature profile in the area of the SP flooding pilot site was estimated. Calculations have shown that the injection of unheated water over a 12-year period significantly cooled the reservoir in the pilot area. The temperature in the area of the well designed for injection of the SP composition is 70 °C, which is 17 °C less than the initial reservoir temperature and with further injection of the unheated SP composition, the temperature in the area of this well will fall. This circumstance must be taken into account when choosing surfactants and polymers that must have effective oil-displacing properties over a wide temperature range.
Advanced Technologies Application - A Full Subsurface to Surface Integrated Approach to Meet the Challenges of a Complex Multi Reservoir Carbonate Field CO2 EOR Development
Authors: Xu Siqing , Baslaib Mohamed , BinAmro Ahmed
Published: October 2022

Miscible CO2 flood - similar to miscible hydrocarbon gas injection - is a well-established proven EOR development scheme. There have been a large number of CO2 EOR developments worldwide, with deployment in both carbonate and clastic reservoirs. Potential controlling factors on CO2 EOR incremental production and recovery are well understood and widely published. This paper presents an integrated CO2 EOR development study, with emphasis on advanced technologies application - a full subsurface to surface integrated approach to meet the challenges of a complex multi reservoir carbonate field CO2 EOR development. This paper is a follow up companion paper, presenting additional results, to a previous paper by Xu S. et al (2021). Holistic detailed studies were performed expediting advanced technologies deployment under a CCUS Hub decarbonisation approach. Based on field pilot testing results, multi advanced technologies from subsurface to surface were assessed in a fully integrated manner. These include Maximum Reservoir Contact (MRC) wells, Limited Entry Liner (LEL) and fishbone drilling advanced completion technologies, fishbone surface networking, CO2 recovery unit etc. Significant improvements in incremental oil recovery and project economics were obtained.
Pilot Tests of Enhanced Oil Recovery by Integrating Conformance Control Treatment and Surfactant Flooding for Low Permeability Reservoirs
Authors: Zhou Nancy Chun , Lu Meng , Liu Yajun , Li Jianshen , Liu Fuchen , Li Wenhong , Wu Xinwei , Rao Tianli , Zhao Kun , Yang Lu , Wang Yajun , Gu Renchao
Published: October 2022

For fractured low permeability reservoirs, there are challenges to enhance oil recovery after water flooding with high water cut contents. Because of unsatisfied surfactant polymer flooding, we explored the integrated EOR techniques of conformance control treatment and surfactant flooding. This paper analyzes the results of pilot tests with four injectors and 16 producers and concludes the effectiveness of integrated EOR techniques.

Based on lab results of conformance control core flooding tests and surfactant based chemical EOR reservoir core flooding experiments, we did pilot simulation studies to develop pilot design parameters. Then through history match and detailed compositional simulation, we made EOR integrated technology design and compared several injection scenarios by predicting the potential performance. Finally, an integrated EOR technique with two conformance control treatments and surfactant flooding was selected and executed for three injectors in the interested pilot block. For the fourth injector, only surfactant flooding was used to compare.

Lab results of conformance control core flooding tests showed the efficiency of plugging and a good fluid diversion performance of conformance polymer agents. Surfactant based chemical EOR reservoir core flooding experiments resulted from 70% to 98% residual crude oil recovery. The experimental data obtained was implemented in a numerical simulator model to find the potential incremental recovery associated with conformance control treatments and chemical flooding. A refined sector model used to further evaluate the effect of them. Positive simulation results boost pilot tests. Five fluid injection slugs including the cleaning slug, pre-flooding slug, near wellbore plugging slug, in deep conformance control slug, and surfactant flooding slug were run for three injectors in the range of eight to ten months of treatment. In the interested pilot block, the monthly decreasing rate of oil production dropped from 3.58% before treatment to −1.04% during treatment. Comparing the oil production data from the fourth injector with those from other three injectors, we observed monthly oil production rate increases from 4.25% to 7%. These results highlighted the importance of conducting a conformance control treatment before surfactant flooding, especially in fractured low permeability reservoirs.

The results of pilot tests in this work shed light on designing integrated EOR techniques. These positive results of controlled high water cut and improving oil production are promising enough to go towards a larger field project.
SmartWater Synergy with Chemical EOR: Studying the Potential Synergy with Surfactants
Authors: AlSofi Abdulkareem M. , Wang Jinxun , Salaun Mathieu , Rousseau David , Morvan Mikel , Ayirala Subhash
Published: October 2022

The potential synergy between SmartWater and various EOR processes has recently attracted significant attention. In previous work, we demonstrated such favorable synergy for polymer floods not only from a viscosity standpoint but also in terms of wettability. Recent studies suggest that such synergy might extend to even surfactant floods. In this work, we investigate the potential synergy between SmartWater and surfactant flooding. Opposed to previous work, the potential synergy is investigated from ground zero. We concurrently developed two surfactant formulations for conventional high salinity injection water and low salinity SmartWater. The formulations were designed for an actual carbonate case exhibiting harsh reservoir conditions. To design the two surfactant-polymer (SP) formulations, we followed a systematic all-inclusive laboratory workflow. Oil displacement studies were performed in preserved core samples using the two developed formulations with conventional injection water and SmartWater. The results demonstrated the potential of binary surfactant mixtures of Olefin Sulfonate (OS) and Alkyl Glyceryl Ether Sulfonate (AGES) for both waters. The designed binary formulations were able to form to Winsor type III emulsions besides achieving ultralow interfacial tensions. Most importantly, in terms of oil displacement, the developed SP formulations in both injection water and low salinity SmartWater were capable of recovering more than 60% of the remaining oil in core post waterflooding (ROIC). A key novelty of this work is that it investigates the potential synergy between SmartWater and surfactant-based processes from the initial step of surfactant formulation design. Through such from-scratch evaluation, we demonstrate that surfactant-based processes exhibit limited synergies with SmartWater. Comparable processes in terms of performance can be designed with both high-salinity and low-salinity waters. It is also quite possible that the synergistic benefits of SmartWater on oil recovery cannot be effective in SP flooding processes especially under optimal salinity conditions.
Innovative Process to Set Record Length of Cement Plug in an Offshore ERD Well
Authors: Latinovic Mile , Verhozin Andrey Konstantinovich , Klementyeva Natalia Andreevna
Published: October 2022

From an operator’s standpoint, well abandonment is viewed as a costly, but necessary, process that does not typically add value. The service company is tasked with performing the abandonment operations safely, efficiently, and economically without issues. This paper presents a technique for the placement of an extremely long, single cement plug using sacrificial pipe and a special release tool under conditions that significantly exceeded the limits attempted by the industry previously.

The plug and abandonment (P&A) process with conventional balanced-plug methods presents many challenges, particularly in the case of multiple cement plugs in a long, extended-reach drilling (ERD) section covering several permeable intervals. The most common issue is cement contamination, which results in poor zonal isolation caused by insufficient slurry strength. A special downhole tool was used for this operation, which provided a reliable solution for placing one long cement plug instead of placing up to 10 balanced plugs, thereby decreasing operational risks and saving rig time.

This fit-for-purpose tool is torque-capable, which enabled running sacrificial pipe in a wellbore with high inclination, where right-hand torque up to 30,000 lbf-ft was necessary to reach TD. Equipment could be drillable or nondrillable; in this case, a nondrillable solution consisting of 7-in., 26-ppf steel casing used as the sacrificial pipe. A dart was used for the displacement of cement through the pipes and activation of the releasing mechanism to place the sacrificial pipe in the hole. The P&A operation was performed on a 9750-m MD ERD well with an inclination of 78 to 84° in the abandonment interval of an offshore drilling rig in Russia. One cement plug covered 2550 m of sacrificial pipe, isolated several zones, and saved two days of rig time.

This procedure did not require pulling pipe out of cement. The risk of cement contamination was significantly diminished, and further operations could be performed immediately after the release. An added benefit was the reduction in contaminated mud that would require treatment and disposal compared to the multiple conventional balanced-cement plug techniques. Tool manufacturers are challenged to continue developing higher torque capacity tools to meet the demands of future ERD P&A activity.