bluuebunny/crossref_metadata_2025 huggingface dataset:
Management of Change: A Journey towards Simplifying the MOC Process in ADNOC Onshore
Authors: Al Harbi Mosleh , Viswanathan Rajesh , Al Shamsi Marwan
Published: November 2018

Management of Change is a standardized process to manage change and ensure that risks to the integrity of assets are within an acceptable level. This is applicable for all temporary and permanent changes, technology, facilities, equipment, operations and organizational arrangements. This will ensure that risks are As Low As reasonably Practical (ALARP). During the Operation phase of the facilities, a robust management of change process could prevent Major industrial accidents. (Lessons learnt from incidents like Flixborough).

This paper will detail the journey over a decade in ADNOC Onshore where the MOC process has evolved from a paper based system to an auditable electronic application.

The MOC process in ADNOC Onshore has evolved as a mature electronic application meeting all the minimum requirements as per the standard and ensuring that the risks arising out of the changes are managed within ALARP.

Management of change is governed by corporate integrity standard (CIS-17) and the process was rolled out as an electronic application in 2012.Till 2015 the number of backlogs in the MOC application grew to 800+. The major reasons for the bottlenecks were identified as complex approval cycle, business process, deliverables were not clear, controls were not enforced by the system and performance monitoring was poor. The application had multiple modules and the records were getting stuck leading to delay in approvals. Some of the key stakeholders were missing in the workflow.(e.g. MOC Forum, Technical authority)

MOC Enhancement program was developed to focus on four main pillars. (Developing new business Process, Reducing Backlogs, Develop new application and Roll out of the new process). The new business process was approved by all stakeholders and issued for implementation by the CEO. Backlogs were reduced after screening workshops with all stakeholders from 800+ to 121 cases. New Application was developed as per the revised business process embedding controls and ensuring the deliverables at each stage are met. The new application was rolled out successfully in July 2017 and this was followed up with series of awareness workshops and training all facilities.
An Innovative Fluid Approach to Reservoir Drilling and Sand Screen Deployment: When Reality Meets Design and the Lessons Learned
Authors: Webber Claire , Langford Marc
Published: November 2018

An engineered dual-purpose drilling and screen-running fluid was required to achieve optimum oil production with increased operational efficiency in a tight pressure window environment. The fluid needed to pose minimal formation damage risk while drilling and avoid completion damage through plugging of the standalone sand screen. This required a balance between bridging material content and particle size distribution (PSD), and a low fluid rheology to minimize the equivalent circulating density (ECD). The wide temperature profile and predicted restrictive narrow pressure margin in the well favored the use of a low ECD Non-Aqueous-Fluid (NAF). An organoclay-free NAF solution was selected. To reduce solids loading and ECD further, the fluid was designed with a brine phase that was high-density calcium bromide. Sized ground marble was selected to bridge the largest pore throats (42-μm) in the reservoir sand and still be screened quickly to avoid plugging of the 150-μm 6 5/8-in. standalone sand control production screens. Fluid optimization was achieved through rheology, stability, and formation-damage testing. The return permeability on cores/matched sandstone of >97%, indicated minimal formation damage risk when drilling and after production flowback/solids removal. In the field, the reservoir was drilled without major issue (i.e. no differential sticking, no down-hole losses) and the fluid quickly reached production screen test (PST) specifications prior to running screens. The sand screens were installed without issues. Although the sand section was significantly shorter than planned, the production from ~160 ft of net pay when the well was initially flowed produced as expected. After subsequent tie-in to the host floating production storage and offloading (FPSO) unit and upon choke opening, a gradual drop in production was observed. An acid job was performed via a subsea vessel-based operation and the planned production target exceeded the original clean-up well productivity.
Advanced Real-Time Reservoir Characterization Utilizing Full Magnetic Resonance Data While Drilling: A Case Study from Abu Dhabi
Authors: Al-Zaabi Fatema , Amer Mohamed , Al-Jaberi Salem , Afzal Nusrat , Abdelbagi Mohamed , Deng Lichuan , Soliman Ahmed , Kieduppatum Piyanuch , Bhatt Pranjal , Fernandes Warren
Published: November 2018

Reservoir A is an Upper Jurassic reservoir in offshore Abu Dhabi, composing layers of dense anhydrite and porous mixed lithology of dolomite and limestone. Petrophysical study from multiple wells suggests that the rock quality within the reservoir has significant lateral and vertical variations that can result in different flow capacities. Consequently, it is crucial to identify the rock quality variations and the consequent flow capacity in horizontal wells to optimize development plan, ideally in real-time. However, these lateral and vertical variations are not visible from conventional porosity (density / neutron) logs, making identification of rock quality very challenging. This paper introduces an innovative magnetic resonance (NMR)-based real-time method of permeability prediction and rock typing.

Wireline logs including NMR were acquired in a pilot well, providing porosity and extensive T2-based information (permeability index, irreducible and movable fluid volume and porosity partition). Routine core analysis was also available to calibrate the NMR data, achieving a suitable correlation for NMR permeability index calibration in this field. Several rock types could be identified with the Windland R35 technique using porosity and calibrated permeability from NMR. This identification was then validated by rock types from cores. The application of knowledge gained from the study led to advanced reservoir characterization solely based on the NMR log. The process was applied to high-angle and horizontal (HAHZ) wells where the NMR full-spectrum log while drilling was available.

Several slanted wells were drilled with a fit-for-purpose logging-while-drilling (LWD) suite including NMR for geo-steering and formation evaluation. The real-time LWD NMR data helped trace a remarkable change of irreducible water level through certain layers, suggesting that the subzones of Reservoir A changed pore geometry and rock type laterally, resulting in variations of flow capacity and reservoir performance.

In one example, this method indicated unexpected good rock quality in one of these subzones considering the experience from offset well. Subsequently, the LWD formation-testing tool confirmed the result with mobility measurements, proving the NMR-based methodology was valid.

This process normally applies to memory data after drilling, playing a key role in designing completion strategy in a timely manner. The process is also available in real-time while drilling if full NMR data is transmitted to surface, serving as a safer logging-tool for identification of sub-zones with additional valuable information compared to regular porosity tools with chemical radioactive source.
A Workflow to Integrate Core and Image Logs in Order to Enhance the Characterization of Subsurface Facies on Carbonate Reservoirs, Offshore Abu Dhabi
Authors: BinAbadat Ebtesam , Bu-Hindi Hani , Lehmann Christoph , Kumar Atul , AL-Harbi Haifa , AL-Ali Ahmed , Al Katheeri Adel
Published: November 2018

In this study, core and log data were integrated to identify intervals which are rich in stromatoporoids in an Upper Jurassic carbonate reservoir of an offshore green field Abu Dhabi. The main objective of this study was to recognize and stromatoporoids floatstones/rudstones in core, and develop criteria and workflow to identify them in uncored wells using borehole images.

The following workflow was used during this study: i) Identification of the stromatoporoid feature in pilot wells with core and borehole images, ii) Investigate the properties and architecture of stromatoporoid bodies, iii) Integrate the same scale of core observations with borehole images and conventional log data (gamma ray, neutron porosity and bulk density logs) to identify stromatoporoid-rich layers, iv) Performing a blind test on a well by using the criteria developed from previous steps to identify "stromatoporoid accumulations" on a borehole image, and validate it with core observations.

In the reservoir under investgation, stromatoporoid floatstones/rudstones intervals were identified and recognized both on core and borehole image in the pilot wells. These distinct reservoir bodies of stromatoporoids commonly occur in upper part of the reservoir and can reach to a thickness of around 20ft. The distribution and thickness of stromatoporoid bodies as well as growth forms (massive versus branching) were recognized on core and borehole images. The accumulations varied between massive beds of containing large pieces of stromatoporoids and grainstone beds rich in stromatoporoid debris. The massive beds of stromatoporoid accumulations are well developed in the northern part of the field. These layers can enhance the reservoir quality because of their distinct vuggy porosity and permeability that can reach up to several hundred of milidarcies (mD). Therefore, it is important to capture stromatoporoid layers both vertically and laterally in the static and dynamic model. Integrating borehole image data with core data and developing a workflow to identify stromatoporoid intervals in uncored wells is crucial to our subsurface understanding and will help to understand reservoir performance.

Integration of image log data which is calibrated to core and log data proved to be critical in generating reservoir facies maps and correlations, which were integrated into a sequence stratigraphic framework as well. The results were used in the static model in distribution of high permeability layers related to the distribution of stromatoporoids.
Failure Predictive Analytics Using Data Mining: How to Predict Unforeseen Casing Failures?
Authors: Noshi C. I. , Noynaert S. F. , Schubert J. J.
Published: November 2018

Despite numerous studies in the subject matter, industry has yet to resolve casing failure issues. A more interdisciplinary approach is taken in this study integrating seventy-eight land based wells using a data - driven approach to predict the reasons behind casing failure. This study uses a statistical software in collaboration with Python Scikit-learn implementation to apply different Data Mining and Machine Learning algorithms on twenty-four different features on the twenty failed casing data sets. Descriptive analytics manifested in visual 8representations included Normal Distribution Charts and Heat Map. Principal component Analysis (PCA) was used for dimensionality reduction. Supervised and unsupervised approaches were selected respectively based on the response. The algorithms used in this study included Support Vector Machine (SVM), Boot strap, Random Forest, Naïve Bayes, XG Boost, and K-Means Clustering. Nine models were then compared against each other to determine the winner. Features contributing to casing failure were identified based on best algorithm performance.
Jacket Design to Accommodate Offshore Levelling
Authors: N Nagaraju , Kumar Chaithanya , Shirsat Priyanka , Varghese Nitin
Published: November 2018

Industry standard requires jacket to be levelled with in the installation tolerance without overstressing the piles and the jacket. It is noted that jacket levelling analysis is not normally performed at design stage and may not have an established acceptable design criteria as it is difficult to simulate the exact field conditions in an analysis model. In deeper waters where most of the jackets are battered, piles and jacket can get overstressed if an acceptable levelling tolerance across piles are not defined in the installation procedure. As the jacket and pile are not connected during installation phase, the restraint offered by the pile depends on the gap between the jacket leg and pile while pulling one corner of the jacket. Depending on the jacket level and the gaps at the mud level during piling, the self-weight of the jacket may not be completely supported by the mudmat as the piling progress. Soil strength mobilised at installation may be different from the full strength mobilized during operating conditions. This gives raise to many possible restraint scenarios to be simulated for analyses. Further these design simulations are complicated by the actual clearance at site and the stage of the levelling as the levelling can be done at any time during piling. Also, the actual force required to level the jacket are noted to be generally less than the one predicted by the analysis. This paper presents the methodology used to perform the jacket levelling analysis for a jacket with four legs, describes the procedure developed to monitor the levelling operation at site and documents the field measurements for a platform installed by McDermott.
Near Real Simulations with Wireline and Production Testing Surveys in the Oil and Gas Industry
Authors: Chinchayan Gustavo , Whabi Anoop , Mittal Tarsem
Published: November 2018

In this highly competitive industry, technology and perfection in service delivery makes an organization stand out from the rest. One of the key contributors to achieving the highest level of service delivery is equipping the workforce with the required procedures, knowledge, and skills. The blended learning approach must include sufficient classroom sessions. A well-designed hands-on training infrastructure emulates the field environment under the controlled conditions of a training center.

A training facility was designed with the objective to simulate as many challenges and scenarios encountered in field operations. The facility design enabled the field crew to understand and safely apply procedures to deliver services above customer’s expectations.

A project that included drilling four wells was incorporated in the near-real simulations. The facility was equipped with an overhead gantry to enable lifting operations and interventions as well as labs to survey the wells with e-line. An additional Testing and Production Services flow-loop facility equipped with conventional and recent-generation multiphase-measurement equipment can also interact with wells. Bringing several product lines together under one roof has the potential to optimize resources and to deliver packaged solutions to the customers. One such example is the collaboration of Wireline Services with Testing and Production Services.

The core objective of this facility was to design a downhole environment focused on the concepts of well integrity, well isolation, production logging, cased-hole and open hole evaluation. Initial simulations in the facility enabled understanding of cement evaluation with different cement slurry weights. These simulations also enabled evaluating casing integrity with different casing thicknesses and different internal and external casing anomalies, which led to appreciating the vertical resolution capabilities of downhole sensors. Furthermore, the simulations enabled cement evaluation through fiberglass pipe, or glass-reinforced plastic (GRP).

The created environment will facilitate witnessing the behavior of modern sensors to evaluate anomalies through adjacent casings. It will provide an environment to test pulse-neutron tools to evaluate and detect water fluid movement behind casing. It enables grasping the concept of electrical log correlation for perforating services with gamma ray, casing collar locator (CCL), or tubing-conveyed perforating (TCP) assemblies, and it instills confidence to place the assemblies at the correct depth in a well. It was also planned to provide visualization while running production logging sensors with different flow and volume rates of water, oil, and air in conjunction with the Testing and Production Services flow-loop capabilities.

Such a blended-learning approach that covers multiple product lines creates immense value.
Digital Twin Through the Life of a Field
Authors: Føllesdal Tjønn Are
Published: November 2018

The global energy industry is being radically transformed by increased access to data and digitalization of tools and processes. When data is harnessed effectively and then combined with engineering insight it has the ability to radically improve how energy assets are designed, operated and optimized from concept and front end design all the way through the life of the field to decommissioning.

Aker Solutions has developed a data platform and series of software applications which together form a digital twin capable of optimizing energy operations at a product, facility and field level integrating subsea and topside facilities.

The digital twin, conceived during the early concept phase (or retrofit to existing assets), draws together diverse data sources into an integrated format which can be managed and enriched as the asset progresses through its lifecycle. Software applications built on this platform include: Using knowledge-based and adaptable building blocks, our early phase software application accelerates the development of concepts with the ability to rapidly explore different options and adjust and optimize to different customer driven variablesDuring detailed design phase, software applications are used to drive engineering automation and ensure that safety is built inherently into the designSimulation software applications are used to test and evaluate complex installation operations in a virtual environment before any offshore operations take placeDigital twin can add significant value during operations and maintenance activities with performance and integrity data collated and visualized helping to make informed decisions to ensure production optimization and continuityAt a product level, Aker Solutions’ connected subsea equipment uses software applications and analytics to perform condition monitoring and enable predictive maintenance, maximizing production uptime

This digital thread allows data to seamlessly transition across asset phases enabling engineers, operators and asset managers to make informed and confident data-driven decisions; increasing efficiency, reducing cost and reducing risk.
A Robust Production Engineering Strategy for Extended Reach Well for Sustained Performance
Authors: Othman Alaa Amin , Ali Yasser , Sau Rajes , Al Kiyoumi Ahmed
Published: November 2018

One of the most giant offshore multi-reservoir oil fields in the world has been developed using vertical, deviated and short horizontal wells drilled off-shore from wellhead platform towers. Towards the concept of cost optimization, further redevelopment of the oil field was planned using extended-reach long horizontal wells with throws greater than 18,000 ft and measured depths greater than 25,000 ft with some wells exceeding 35,000 ft, from artificial built islands by reducing the number of wells required to drain the reservoir with improving recovery. In order to enable transition to such concept, new well design strategic concepts were required to come up with the robust well completion design (both upper and lower completions) that is expected to be fit-for-purpose for 30+ years – well life time. Lots of uncertainties and challenges are faced in order to get to the goal of understanding different reservoirs behaviors such as, for better reservoirs development relying on dynamic reservoir models combined with actual geological, petrophysical, seismic and production data. Each piece of information yielded a certain potential that led to a certain completion design based on available data and expectations.

This paper will discuss the upper and lower completion designs, execution and performance from production engineering perspective to maximize productivity for the whole life cycle of this long horizontal wells. The extended lateral length in these wells warrants innovative designs in upper and lower completions as traditional completion designs no longer valid in addressing the challenges in these wells. The key well design and planning process involves designing the upper completion – tubing, gas lift system, downhole gauge and lower completion liner – Pre-perforated liner (PPL), Limited-entry Liner (LEL) or Inflow Control Devices (ICD) with annular isolation with packers, efficient initial start-up and clean up strategy, regular monitoring well performance and surveillance (e.g. downhole pressure monitoring, PLTs, fluid sample analysis etc.). The paper will also address the challenges in long horizontal wells such as accessibility, production/injection conformance and effective stimulation of the laterals.
Risk-Adjusted Underwater Inspection Intervals for Steel Piled Jackets
Authors: Foltz Raymond , Younan Adel
Published: November 2018

Inspection intervals have been long established in some jurisdictions around the world based on an assessment of acceptable risk from experience, judgment, and observations of past damage. In areas that do not have the benefit of decades of experience, the designated inspection intervals may be inheriting intervals from another region of the world, and in doing so, potentially subscribing to inspection interval frequencies that assume less or more risk than has been deemed acceptable in other areas of the world. This study investigates two prototype steel piled jacket platforms subjected to metocean conditions present in several areas of offshore development around the world, with the objective to investigate the relative fatigue performance of the prototype structures in these varied environments. The relative performance of these various locations may lend insight into the implementation of risk-consistent inspection intervals for structural integrity maintenance programs.
Nearbalanced Nitrified Foam Drilling: A New Frontier for the Drilling of Depleted & Fractured Carbonates - A Study on the Design, Execution, and Results on Multiple Wells
Authors: Khalid Ali , Ashraf Qasim , Luqman Khurram , Moussa Ayoub Hadji , Nabi Agha Ghulam , Baig Umair , Mahmood Amer
Published: November 2018

Carbonate platforms are one of the most common reservoirs on earth, and as such are one of the most frequently explored.

Sulaiman fold belt in Pakistan is known to contain multiple hydrocarbon bearing carbonate formations. One such formation is the Sui Main Limestone formation. The formation when first discovered was known to contain over 9.5 Tcf of gas in Sui field, and up to 5.0 Tcf of gas in the neighboring Zin field. Over the years due to extensive field development and production, the Sui Main Limestone reservoir has been driven to depletion. Operators are now looking to explore deeper horizons in the same fields.

The challenge in deeper exploration of the subject fields is now a depleted pressure of about 2.1 ppg EMW of the Sui Main Limestone formation. In addition to the low pressure, the SML formation is highly fractured in nature. These two factors resulted in massive circulation losses when an attempt to drill a well was made through the approximately 650 m width of the SML formation. To cure losses, operators resorted to heavy LCM pills, and numerous cement plugs. Losses in the hydrocarbon bearing SML formation also led to well control and stuck pipe events on multiple occasions. Successful drilling through the whole width of SML formation would sometimes take up to almost 3 months. Drilling time and lost circulation materials thus generated excessive well costs.

The operator sought a solution which would eliminate circulation losses in the SML formation, and cut down drilling time substantially. An underbalanced system was first considered for achieving these objectives but as the SML formation bore sour gas and excessive equipment would be required for a safe underbalanced operation, the option was ruled out. A nearbalanced nitrified foam system was thus designed to be able to drill the SML formation delivering the same benefits of an underbalanced operation without its perils.

By applying a nearbalanced nitrified drilling technique, operators in the subject fields were able to cut down the drilling time to about 3-5 days, achieve a substantial increase in drilling performance, and practically reduce the NPT to 0.

This paper studies the planning & design of a nearbalanced nitrified foam system for two different wells with hole sections of size 17", and 8-1/2". The paper also discusses the equipment selection, the wellsite execution, and the results achieved by applying nearbalanced nitrified foam drilling in the subject fields.
Impact of Drilling Practices on Well Integrity and Production: An Analysis and Assessment
Authors: Saumya Sachit , Sarkar Sujit Kumar , Singh Juli , Kumar Ajit , Agarwal Gaurav , Khambra Isha , Vij Jitesh , Das Bhaswati , Shedde Preetika , Majumdar Chandan , Pabla S
Published: November 2018

Drilling is carried out in the very early stage of the well and it is critical for ensuring smooth execution of every aspect of well construction such as faster drilling, better hole cleaning, superior logging, running casing efficiently, maintaining wellbore integrity and achieving economic production. This paper will demonstrate the significance of best drilling practices to achieve good wellbore geometry, which has a profound effect on total well construction and production time and cost and sometimes even determine the success of the well.

Poor wellbore geometry, because of improper choice of drilling system i.e. mud motor or rotatory steerable, is generally related to the washed out and/or spiraled wellbore. Washed out hole is recognized by using calipers, however, the hole spiraling is difficult to detect at the early stage of the well. In spiraled holes, it becomes virtually impossible to get a good cementing job done. The poor cementing conditions behind the casing are identified using ultra-sonic images or high amplitudes values of CBL/VDL. These channels behind casing are, a clear threat to production and life cycle of the well. It is widely assumed that the squeeze jobs are an option to improve cement behind casing, however, it does not hold true in case of a spiral borehole. This paper compares the wells, drilled with different drilling system and their impact on the wellbore geometry. It also exhibits the aftermath effects on wellbore construction, well integrity and production.
Best Practice - 2oo4 Voting Logic for Centrifugal Compressors Radial Vibration Trip
Authors: Surange Vivek , Kokku Anil Kumar
Published: November 2018

It is important to carefully consider safety, reliability, maintainability, environmental impact and financial losses that can result from unplanned equipment outages due to faulty instrumentation (spurious trips) of Centrifugal Gas Compressors during its operation. It is all the more significant to consider the above aspects specifically during the design phase of compressor systems. Spurious tripping of equipment contribute to the production loss, risk to operations and also impacts the carbon footprint due to unwanted flaring. Optimizing the trip voting logic can reduce such spurious trips and increases the availability/integrity of equipment.

This paper provides guidance to rotating equipment/instrumentation engineers to review the existing trip voting logic for radial bearings vibrations of Centrifugal Gas Compressors and explores the possibility of implementing the 2004 voting logic considering both ends of the shaft.

The study highlights the benefit of adopting 2004 voting logic over other voting logics such as 1002 and 2002 for Centrifugal Compressor radial bearing vibrations to minimize the unwanted trips.

2004 voting logic is defined as follows:

If either end of the machine experiences high radial vibration and one of the X or Y probe reaches the trip level, and at the same time, if any other end also recognizes this increase in vibration level and crosses alarm limit of the machine, then it is a vote to trip. If only one of the four probes on the machine shows a high level or high-high level, it can be attributed typically to probe malfunction, and should not actuate a machine trip.

A study to optimize the voting logic was conducted to improve the machine reliability and availability by reducing unwanted trips due to malfunctioning of instruments. The study methodology includes: Evaluation of various industry options and generally proposed Centrifugal Compressor OEMs recommendations and guidelines in API-670.Historical data analysis of operating equipment.Comparison of advantages and disadvantages of the proposed logic (2oo4) over other voting logics i.e. 1oo2, 2oo2.Risk assessement and risk reduction performed by SIL evaluation for these Safety Integrity Functions (SIFs).
Eye in the Sky: How the Rise of Drones will Transfrom the Oil & Gas Industry
Authors: Al Amir Noora , Al Marar Mohamed Saeed
Published: November 2018

Commercial use of drones – inspection drones to be specific – in Oil & Gas sector has been on the rise since around 2010. Leading Multinationals and some North American companies managing petroleum assets are among the first to tailor their inspection procedures incorporating the use of inspection drones. This inevitable switch is based on a rationale – safety of inspection personnel including ease of access to hazardous locations. Other factors that incentivize the use of inspection drones include time savings, lower costs, early warnings, improved data collection and sometimes the only viable option to get first hand information about an emergency event.

Petroleum industry assets are high-value-long-life assets which are built to process / handle hazardous fluids. Operation & maintenance of these assets is a carefully regulated activity under the dictates of regulatory guidance, codes & standards. These compliance obligations burden the operators of these assets to optimize operations based on reliability centered maintenance philosophy. Consequently, inspection drones have in a very short span of time (5 – 10 years), have succeeded in proving their utility to support the operators and asset managers in meeting responsibilities related to the following: A-1. Operational ResponsibilityA-2. Corporate & Social Responsibility (CSR)A-3. Environmental ResponsibilityA-4. Security Responsibility

This paper is an effort to collect and present data signifying the utility of inspection drones for asset management as well as optimized operations – onshore operations related to exploration and production as well as oil transportation.
Full Field Scale Hydrocarbon Gas Enhanced Oil Recovery Project in Offshore Vietnam -Response Analysis and Optimization Practice in Early Stage
Authors: Kawahara Yohei , Sako Yukiya , Chai Zhenjie , Nguyen Chu Chuyen , Murakami Takahiro , Nishizaki Aiko , Dao Cong Thien
Published: November 2018

Rang Dong field in offshore Vietnam has been producing oil since 1998 from a Lower Miocene sandstone reservoir. Upon the achievement of peak oil production in 2002, gaslift and water injection have been applied to maintain oil production. With primary and secondary oil recovery applications underway, a tertiary recovery technique by immiscible hydrocarbon gas enhanced oil recovery ("HCG-EOR") had been studied since 2009. Subsequent to a successful Pilot Test in 2011, a full field scale HCG-EOR with water-alternating-gas ("WAG") scheme has been implemented since 2014. This HCG-EOR application was the first commercial EOR project in offshore Vietnam and attracted attentions in the region. The project has been successfully executed to effectively minimize the decline and contribute approximately 30 percent of oil production rate as of the date of this paper. Numerous efforts for WAG pattern optimization and accurate incremental oil evaluation were attempted.

This paper introduces coupled approach of well performance analysis and reservoir simulation study applied to the WAG optimization and incremental oil evaluation. In line with the theoretical reservoir responses of immiscible gas flooding, all the producers were classified into 3 groups by different types of performances following the WAG injection. By coloring the different groups on the well location map, reservoir engineers were able to understand the regional characteristics of response and managed to optimize WAG by allocating more gas to the regions where incremental production were dominated by tertiary recovery mechanism. For incremental oil evaluation, either decline curve analysis ("DCA") or compositional reservoir simulation is common practice, however, both techniques have its strengths and weaknesses. In this study, reservoir simulations for "past" incremental oil evaluation are always double-checked by DCA, and then prediction runs are performed. Such exercise could deliver the incremental oil evaluation of high confidence.

In addition to discussion related to such subsurface evaluations, this paper also introduces lessons leant and mitigations on actual field operation with focus on intensified sand production, injectivity deterioration and back pressure surge after gas breakthrough.
Emissions Management and Ambient Air Quality Monitoring in Upstream Oil and Gas Sector - Highlights of KOC's Air Compliance Management Program ACMP as an International Best Practice
Authors: Hussain Zainab , Haider Mohammad , Asker Ali
Published: November 2018

The Air Compliance Management Program (ACMP) is a unique project undertaken by the Kuwait Oil Company to identify and address the impact of air pollutants originating from upstream exploration and production operations on the environment in general and on human health in particular. It was the first-ever joint venture of its type between the industry (Kuwait Oil Company) and regulators (Kuwait Environment Public Authority) in this region. The objectives of the project was to utilize various advanced technologies to provide an exemplary way of managing emissions from KOC's operations and reducing their impact on human health.

The project included establishing an air quality-monitoring network, developing emissions inventories with dispersion modelling techniques to determine human health risk, developing visual based emission information, using hyperspectral remote imagery for surrogate estimation and remote sensing information for tracking pollutant masses during the project. Subsequently, an innovative source apportionment study was undertaken, utilizing satellite based techniques to define pollutant source contributions from various sources and develop abatement strategies. The study utilized emission data from all sources within Kuwait as well as emissions from marine vessels, road traffic and included regional emissions from other countries as well to estimate KOC's contribution to emissions based on monitored air quality data.
Improving Transport of Nanoparticles in Carbonate Media by pH Alteration
Authors: Felix Servin Jesus Manuel , AlSadeg Hala A.
Published: November 2018

Improving long-term stability and reducing retention are active areas of research for nanoparticle-based technologies for the oil and gas industry. A common strategy to improve nanoparticle stability and reduce retention is the use of polymer and/or surfactant coatings. This manuscript describes a method to improve the transport properties of FITC-dextran through carbonate media. The proposed method is based on the observation that during Alkaline-Polymer-Surfactant flooding, polymer retention reduces as pH increases, likely as a consequence of transitioning through the point of zero (PZO) charge for the porous media. Multiple alkali agents have been identified in the past, but most of them are incompatible with brines containing a high concentration of divalent cations, such as Ca2+ and Mg2+, and are therefore incompatible with carbonate reservoirs. Sodium metaborate, however, has been reported as being compatible with hard brines and carbonate reservoirs. This study evaluates the effectiveness of sodium metaborate as an alkali agent to reduce FITC-dextran retention through carbonate matrices as a proxy for dextran-coated nanoparticles.

A series of transport experiments were conducted using chromatography columns packed with fine marble powder to evaluate the impact of pH on FITC-dextran retention. The columns were initially saturated with treated saline water and let rest for three weeks followed by the injection of three pore volumes (PVs) of treated saline water for washing purposes. Next, five PVs of a solution of FITC-dextran dissolved in treated saline water (with or without sodium metaborate tetrahydrate) was injected through the columns. Finally, 5 PVs or treated saline water (with or without sodium metaborate tetrahydrate) were used to displace the injectant. Effluent samples were collected during each phase of the experiment and analyzed using a fluorescent spectrometer. Fluorescence intensity data was converted to concentration and plotted as a function of injected volume to create a breakthrough curve and to estimate FITC-dextran recovery.

The results show a slight decrease in retention when using sodium metaborate to increase the solution pH. FITC-dextran recovery was estimated to be 47% for the injectant without sodium metaborate tetrahydrate, and 49% for the injectant with it. This trend is in agreement with previous studies looking at polymer retention and FITC-dextran retention. The experiments suggest that pH plays a significant role during the flushing phase.

The ability to transport nanoparticles through oil reservoirs can lead to a whole new range of applications including smart tracers, contrast agents and improved EOR agents and other technologies for reservoir characterization.
Novel Perforating Design Delivers Production Targets Safely and Efficiently in Gas Producing Wells
Authors: Awad Nasr , Abd El Sattar Ashraf , Sheha Mohamed , Moustafa Abdallah , Vazquez Maria Leticia , Farid Ahmed , Mohamedien Alaa , Manaa Mohamed
Published: November 2018

Perforating a gas well efficiently requires applying technological advances to carry out a safe operation without compromising well productivity.

In this paper, is discussed the application of a pre- job plan methodology called perforating well on paper to the perforation operation of SITRA 3-4.

This methodology involved tension simulation, perforating gun and charge selection, conveyance hardware optimization, best underbalance value selection, as well as modeling of gun shock, gun movement and reservoir behavior when shooting multiple zones with different pressure regimes. Simulation methodology was performed as well real time during the perforating job to optimize static and flowing underbalance without compromising the safety of the operation and maximizing production gains.
Applications of Machine Learning and Data Mining in SpeedWise® Drilling Analytics: A Case Study
Authors: Ma Zheren , Karimi Vajargah Ali , Lee Hanna , Kansao Rami , Darabi Hamed , Castineira David
Published: November 2018

The daily drilling report (DDR) contains the daily activities and parameters during drilling and completion (D&C) operations that can be used to identify the bottlenecks and improve efficiency. However, the datasets are large, unstructured, text heavy, not correlated to other datasets, and contain numerous gaps and errors. Thus, conducting any meaningful drilling analytics becomes cumbersome. In this paper, an innovative method is introduced to automatically clean the data and extract intelligent analytics and opportunities from these reports.

Natural language processing (NLP) and deep neural network (DNN) models are developed to extract information from unstructured DDRs. Numbers of interest (such as depths, hole sizes, casing sizes, setting depths, etc.) are extracted from text. Drilling phase, non-productive time (NPT) and the associated types are predicted with DNN models. With 30% of the dataset for training, accuracies achieved on the remaining data include 87.5% for drilling phase, 90.7% for time classifications (productive or non-productive), and 89% for associated NPT types. Then, the D&C datasets are integrated with other data sources such as production, geology, reservoir, etc. to generate a set of crucial drilling and reservoir management metrics.

The proposed method was successfully applied to several major oil fields (with total of more than 2,000 wells) in the Middle East, North America, and South America. Here, a case study is presented in which the developed method was applied to more than 200 wells drilled from 2012 to 2016 in a major oil field. By using the proposed method, the data processing and aggregation time that used to take months to accomplish was reduced to only a few days. As a result, major types of NPT were rapidly identified, which include rig-related issues such as repair and maintenance (30%), followed by stuck pipe (23%), hole/mud related issues (such as wellbore stability, mud loss, shale swelling, etc.) (20%), and downhole equipment failures and maintenance (14%).

Drilling solutions such as contractual advices, improving the mud formulations, and drilling with a rotary steerable system (RSS) were proposed to possibly mitigate the NPT and improve drilling efficiency. Implementation of the proposed solutions eventually resulted in reducing the drilling time and improving capital efficiency.

Novel technologies such as NLP, data mining, and machine learning are applied to rapidly QC, mine, integrate and analyze large volumes of D&C data. In addition, this novel approach assists D&C obstacles identification and future plan optimization with evident benefits for improving performance and capital efficiency from a reservoir management perspective.
The Temperature Effect on Selecting a Precise Multiphase Flow Correlation to Find Bottlenecks in Production Surface Network Model in Kuwaiti Fields
Authors: Almohammad Humoud
Published: November 2018

The increasing demand for hydrocarbon made it a challenge to maintain the oil production and maximize recoverable reserves in mature fields. Interconnected flowline surface network, of oil producing wells, varying in reservoir pressure, connected to a single processing facility, resulted in network bottlenecks and other flow assurance issues. This study objective is to predict the temperature changing effect on hydraulic flow behavior and optimize the most precise multiphase flow correlation for the selected fields.

The severity of bottlenecks can be profoundly affected by seasonal temperature changes, which require studying and pre-planning to reduce or avoid production losses. A flowline network model had been built and analyzed in-house using a commercial steady-state multiphase flow simulator for one of company's Gathering Centres (GC). GC-XY problematic, high pressure, headers were considered, which are receiving production from several fields in Kuwait. For representative results; comparisons were done for the prediction of multiphase flow correlations in horizontal and inclined pipelines.

The predictions of the Beggs & Brill (1975), the Baker & Gabb (1988), the Dukler et al. (1969), the Mukherjee and Brill (1983), and the Oliemans (1976) correlations and the Xiao (1990) mechanistic model were evaluated in this study. The comparison was limited to a temperature range from −5 to 55 Celsius degrees, light oil with API above or equal 30 degrees, and 6 inches flowline inner diameter. The study displays statistical error comparison between the predictions of each multiphase flow model used and suggests a correlation for the applied conditions in the selected field. Bottlenecks had been found in the network model, and a variety of solutions were proposed and simulated to overcome the bottleneck severity due to temperature changes. The results findings show a significate potential is reducing the bottlenecks severity up to 40 percent in the designed network and production enhancement of 18,000 barrels daily.

Detailed criteria and calculations were stated to compare and select the most accurate multiphase flow correlations for the chosen fields. Also, the project explains a procedure to model the suggested solutions and find the expected enhancement of production. Temperature overestimation can lead to severe bottlenecks, which require dedicated and reliable studies to minimize the losses due to heat transfer effect on oil viscosity and flow behavior.
Initializing High H2S Fluid in a Large Carbonate Gas Reservoir, Onshore Abu Dhabi, UAE into a Dynamic Model
Authors: AlSulaity Maitha , Ghassan Majed , Ali Onood Al , Kaczorowski Norman
Published: November 2018

The western area of Abu Dhabi's Late Jurassic Arab Formation is a huge ultra-sour gas reservoir with an areal gradient in composition. Early on, the data suggested a trend in H2S concentrations along the axis of the field with a sour gas entering from the southwest and migrating to the northeast. This sour gas contaminated the existing reservoir fluid and created the current areal gradient. Gas properties also varied, and in particular, dew point pressure.

This paper describes the innovative methodology used by ADNOC Sour Gas to input the varying compositions into the simulation model. The methodology consists of two major steps. In the first, PVT data was analyzed and correlations between H2S and other components were established. The second step involved using PETREL to create compositional maps.

Ultimately each grid block was assigned a unique composition based on the H2S concentration at that location resulting in a continuously varying compositional gradient. Concentrations of other components were assigned based on the H2S concentration.

The result was a dynamic model which duplicates the areal distribution in composition and accurately predicts the varying dew point pressures using a single Equation of State. Simulation predictions of condensate and sulfur production has been verified by actual plant yields. Four years of production has shown the veracity of the initialization of the composition in the model as no modifications to the original compositional distribution was required.