bluuebunny/crossref_metadata_2025 huggingface dataset:
The Application of Recycled Auto-Tires Rubber as an Effective Drilling Fluid Additive: Towards a Sustainable Oil and Gas Industry
Authors: Elgaddafi R. M. , Al Saba M. , Almarshad A. , Amadi K.
Published: May 2023

In meeting the world's climate-change goals, the oil and gas industry will have to play a significant part, although the specific initiatives chosen to reduce the emissions may vary, re-engineering waste products that contribute to carbon emission into useful recyclable products for the oil and gas industry can significantly contribute to developing a circular economy and sustainable environment.

This study considered recycling finely ground auto-tire rubber as an effective drilling fluid additive. Waste tire, which is a major air pollutant when burned, was collected from a national recycling company. A laboratory study of using the finely ground auto-tire rubber waste as an effective fluid loss control and bridging additive was performed and compared with sized graphite, which is a commonly used bridging material in the industry.

A commonly used water-based drilling fluid formulation was employed as a base fluid for all the experiments. The performance of the drilling fluid containing the waste auto-tire finely ground rubber was assessed by conducting standard rheological measurements and API fluid loss, where concentrations ranging between (0.0 – 10 lb/bbl) were added to the base fluid. The effect of adding the waste auto-tire rubber on plastic viscosity, yield point, apparent viscosity, and fluid loss was assessed. In addition, the possibility of replacing the sized graphite with the proposed material was investigated.

The results showed a significant reduction in a fluid loss by up to 23% by the addition of (10 lb/bbl) of finely ground auto-tire rubber waste to the base fluid (containing 5% bentonite). Furthermore, analysis of the test measurements showed a minor to negligible effect on the rheological properties compared to the base fluid. Also, it revealed that waste auto-tire finely ground rubber can successfully functionalize as a fluid loss additive and completely replace sized graphite as a bridging material, where replacing the sized graphite with the proposed material resulted in a reduction in the fluid loss of up to 21%.

The promising results obtained in this study highlight the huge potential for this initiative in utilizing recycled auto-tire waste materials as a possible drilling fluid additive and demonstrate a sustainable technique with large-scale application in the oil and gas field whilst reducing solid waste disposal and consequent CO2 emissions resulting from burning waste tires.
Forecasting Reservoir Pressure for Vertical Oil Well Using Supervised Machine Learning Model
Authors: Said Laouedj
Published: May 2023

Static pressure is one of the very important parameters for reservoir engineering, it gives us precious information about our reservoir, such as drive mechanisms, quantities of hydrocarbon in place, patterns, communication between wells, fluid behavior in the reservoir, as consequence, the measurement of this parameter must be conducted on periodical basis, to appropriately know the field and build a good model of reservoir.

The advantage of this study can complete other studies that concentrate only on the oil production rate forecasting like Data Driven Production Forecasting Using Machine Learning [1], Production Forecasting in Conventional Oil Reservoirs Using Deep Learning [2], Machine Learning Prediction Versus Decline Curve Prediction: A Niger Delta Case Study [3], Decline Curve Analysis for Production Forecasting Based on Machine Learning [4] ……, in addition of static pressure evolution of wells.

For instance, we can optimize through this study a number of conducted tests to measure static pressure which will minimize operating costs and the probability of accidents occurring the operations, also reduce the shutdown time of wells for completion purpose of such measurement, in addition to the possibility of using this model for other analogue wells that do not have enough pressure measurement, without the need for time and extensive study. Besides, multivariate polynomial regression machine learning algorithm has been developed in this study to predict the evolution of static pressure for existing oil wells.
Remote Drilling Supervisor – Step Changing Approach Aided by RTOC and 5G Technology
Authors: Jalbout Mohammad Muhab , Al Hai Ahmed , Chammout Omar , Al-Rahma Rahma , Al Benali Khaleefa Mohamed , Al Blooshi Saif , El Bagoury Ahmed , Dubey Anurag , Siddique Ashique
Published: May 2023

Digital transformation has been proven to yield commercial success in the oil and gas industry with several reported advantages of value creation and business empowerment. The paper demonstrates the implementation of a breakthrough technology and ideology to steer rig operations in onshore locations in Abu Dhabi, by adopting unified Real Time Operations Center (RTOC) concept. The technology has enabled proactive evaluation of rig operations, integrated different stakeholders in one platform, and supported the decision-making process while providing additional opportunities for young engineers onsite.

The unified RTOC technology approach is distinguished by empowering collaboration across functional departments. It enables higher levels of coordination of daily rig operations by converging processed and unprocessed information sources such as Technological Systems, Drilling Data Management Systems, Analytics, and Geomatics. Specifically for this exercise, the approach benefits are maximized by adopting a new concept to supervise rig operations remotely. The young drilling supervisors are settled to work on rig site, while senior drilling supervisors supports them from the office. One senior drilling supervisor can support 3 rigs at a time, covering exactly all major roles and responsibilities as if he/she is available physically onsite. The wells are monitored thoroughly with RTOC's platforms, associated risks are categorized, and several analytics were performed based on real-time data. CCTV integration with 5G technology braced the concept of monitoring the risky areas at the rig site with seamless footage. The CCTV integration was a step transformation for the proof of concept.
Blockchain Supercharges Digital Well Program towards Cyber-Physical Drilling System
Authors: Samuel Robello , Lakhanpal Vikrant , Kumar Kiran
Published: May 2023

The oil and gas industry is transforming itself into a data-intensive industry with the addition of artificial engineering intelligence, cognitive computing, machine learning, internet of things and robotics. With the growth and expansion, various exponential technologies can carry the energy industry's transformation forward in the new era of cyber-automation and more so on the cyber-physical -automation. Blockchain technology can drastically streamline the current complex matrix of activities from seismic to production and abonnement. The existing integration and management of various disciplines is very expensive, requires several disciplines that are sometimes disjointed and siloed, and is exceedingly complex in the course of the digital well program and as we receive more and more data. With blockchain as a common technology, firms may more easily handle the many digital procedures, operational tasks, diverse vendors, production schedules, and supply chains that affect how the digital well program and schedules are made.

In this paper, the full lifecycle system—which can serve as the lifecycle's template—is discussed. It can be housed on a permissioned blockchain. Blockchain has been discovered to streamline and facilitate open collaboration because to its inherent qualities of trustworthiness and transparent execution of transactions involving numerous parties. By making asset transactions transparent and flexible, it facilitates data sharing among several businesses, providers, and partners, making it simple to connect the real world to the digital one through the use of edge devices and cloud computing. This approach has been discovered to offer crucial characteristics of privacy and auditability while limiting ledger size, in addition to transparency and efficiency. In order to balance the competing demands of privacy and openness, peer identities are concealed from one another while they agree on transaction outcomes. Additionally, data will never be exchanged among blockchain peers without the owners' express permission. Blockchain is a decentralized peer-to-peer digital ledger technology that has a lot of promise for the digital well program. A local peer communicates with an associated anchor peer inside the global network and a common database like Open Subsurface Data Universe in the system, which is built for both intra- and inter-organizational transactions like Open Subsurface Data Universe (OSDU).
Current Casing Running Technologies CRT: Drilling Mindset Versus Makeup Mindset What Missing for Reliable Makeup Operations
Authors: Al Bu Z. , Al-Moyaibed J. M. , Owoeye O. O.
Published: May 2023

Casing Running Tool (CRT) combines many functions of other tools, such as circulation heads, casing and tubing rotation, and connection makeup. The technology's initial design was for drilling with casing. However, it is currently used widely in running and makeup operations of conventional casing and tubulars. This paper aims to identify gaps and opportunities in the current service to reach the full potential of the benefit of the technology as a running and makeup tool; and ultimately achieve automation for makeup operations.

The paper reviews the current CRT types used to analyze pre-operations and during-operation features. Each step of the makeup operations was evaluated and compared to the conventional power tong. The comparison finding summarizes the advantages and disadvantages of CRT versus the power tong. In addition, the paper relates the CRT shortcomings to the mindset of the original designers of the system. The new usage context brought great value but did not fully address the additional requirements to deliver quality makeup operations.

CRT improved HSE by reducing the number of operators in the rig's red zone. In addition, it helped in deploying the casings in challenging well conditions by pushing the casing to target depth and combining drilling and running runs for less intermedial operations. However, the system lacks in makeup operations. The paper claims that CRT requires slight modifications to overcome shortcomings in inspection, communication to the multiple parts of the system, calibration, and control. Designing CRT focusing on quality makeup will result in innovations that will significantly improve the connection makeup reliability and ultimately prepare the system for full automation.
Kuwait's First Successful Implementation of Managed Pressure Cementing in Deep Jurassic Reservoirs of Kra Al-Maru Field
Authors: Ekpe J. , Al-Shehab A. , Al-Othman A. , Baijal S. , Marin G. , Benyounes H. , Aliyeva A. , Alqabandi R. , Selami B. , Al-Fakeh B.
Published: May 2023

The development of Najmah-Sargelu (NJ-SR) limestone fractured reservoir, has a significant role in Kuwait Oil Company (KOC) 2040 strategy. To achieve this objective, hydrocarbon potential across the NJ-SR reservoir will have to be evaluated in the West Kuwait of Kra Al-Maru (Figure 1). First and foremost, this section will have to be drilled to planned section TD, cased off and successfully cemented. This paper discusses KOC experiences and best practices implemented to ensure utilizing managed pressure drilling equipment to achieve a successful 7-5/8-in liner cement job at well depth of 16,945ft. MD (15,756ft. TVD), and reservoir pressure and temperature ranges of 12,000 - 15,000psi and 230 - 280 deg F respectively.

This new approach to cementing is based on Managed Pressure Drilling technology. It addresses running the 7-5/8- in liner and cementing it in MPD mode. A step-bystep procedure is provided that ensures a constant bottom pressure is maintained throughout the process. Risk assessment showing what can go wrong and mitigations are provided, and the method is described in detail to allow readers comprehend the unique case presented in this paper.

Managed Pressure Cementing (MPC) technique in case study well is compared to offset wells in West Kuwait Field where cementing was conducted conventionally. In most cases, the cement bond logs show cement dispersed throughout the annulus with no continuous bond - channels in the cement behind the casing. The most significant new findings from this paper are that, in a couple of wells where there were no losses while pumping cement conventionally- the cement bond logs showed moderate to poor cement behind casing and channels within the cement.

This technology offers opportunity to achieve good cement bonding with liner in fractured limestone which can be problematic due to the risk of losses and the presence of hydrocarbons with high pore pressure in West Kuwait NJ-SR intervals. This novelty approach using Managed Pressure Cementing technique to case and cement liners in West Kuwait fields and tight margin reservoir will ensure good cement bond logs behind casing and improve well testing and completions strategies.
An Additive Manufacturing Process Enables the 3D-Printed Application of Armors for Drill Bits
Authors: Zhang Y. , Sogn H. , Cai M. , Santana R.
Published: May 2023

Materials development, mechanical design, cutting structure modelling/simulation, advanced manufacturing process are the key necessities for producing high-quality, superior-performing drill bits. Among all, the bit body materials and manufacturing method are the key limiting factors for geometric design and bit life. Conventionally processed materials used for drill bit bodies, either a metal matrix body (Tungsten carbide particles infiltrated with copper alloy binder) or a steel body with hand-applied hardfacing material, have reached the limit of certain properties.

Recently, an Additive Manufacturing (AM) method has gained rapid expansion from prototyping to industrial scale production with the capability of building complicated shapes and competitive properties. This paper presents the innovative work that went into developing the AM powder containing extremely hard tungsten carbide particles and directly printing this matrix composite parts then to be used in manufacturing drill bits for challenging drilling applications.

Additionally, other benefits of adopting AM technology include minimized greenhouse gas emission (GHGE); thus, boosting sustainability.

Multiple field application cases with polycrystalline diamond compact (PDC) drill bits dressed with AM components are presented to show the performance improvement over conventional counterparts.
An Integrated Well Completion Technology for Low Permeability Reservoirs in the Middle East: Fracturing, Injection Control and Production Control
Authors: Chunpeng Wang , Yucai Wang , Weixiang Cui , Liangyu Rao , Xueqin Huang , Shuzhe Shi , Zhen Nie , Bohong Wu , Yanna Zhang
Published: May 2023

Horizontal wells in the Middle East are mainly completed with 6-inch open hole, and some wells are put into the screen in the horizontal section. This kind of wellbore structure can meet the production demand in the early stage. But it is not conducive to the later fracturing or acid fracturing, because the open hole section cannot be effectively segmented, and the targeted injection control or segmented production control cannot be carried out after stimulation.

In order to realize the segmented stimulation of the open hole, the secondary completion string is run in on the premise of keeping the existing string unchanged, which is used for segmented fracturing and segmented injection or production control after fracturing. The string consists of open hole packers, switchable sliding sleeves, toe anchor, etc. Each part is connected with 4-1/2 inches’ base pipe. All sliding sleeves are closed when they are lowered, and are opened through soluble rubber plugs. After fracturing operation, the sliding sleeve can be opened by coiled tubing with switch tools and the horizontal pipe string remained as the production pipe string.

Through the laboratory test, the switchable sliding sleeve and open hole packer can be used under the conditions of no more than 180 °C and pressure difference no more than 60MPa, and are resistant to hydrogen sulfide and carbon dioxide corrosion. From 2012 to 2020, the switchable sliding sleeve has been used in 187 wells in the eastern oilfield of China, including 36 vertical wells and 151 horizontal wells, with a total of 1449 sets of sliding sleeves. The maximum pumping rate of hydraulic fracturing is 12 m³/min with up to 21 fracture stages. The maximum temperature is 135°C with up to 12989 m³ of fracturing fluid and 1018 m³ of sand injected into a single well. The maximum well depth is 4995 m (MD) and the maximum vertical depth is 4200 m (TVD).

The technology realizes the segmented stimulation of low permeability reservoirs in the Middle East under the existing horizontal open hole completion conditions, realizes the segmented control of water injection wells and segmented production of production wells, saves the operation cost and prolongs the life cycle of old wells. However, in order to reduce fracturing investment, casing completion is still recommended for new wells with low permeability reservoirs.
Restoring the Well Integrity with Full Bore Access by Using Expandable Steel Technology
Authors: A. Ans Muhammad , Alzori Hussain , Demyanov Alexandr , Seiam Mahmoud
Published: May 2023

Expandable Steel patch has a wide application in oil and gas wells. The patch restores the casing integrity but it poses inside diameter (ID) restrictions leading to difficulties in running completion equipment. This paper focuses on mechanical seal of perforations with full bore access and shares an overview of the general idea, well design, operational plan, successful field installation, and testing of the patch that provided full bore accessibility with a reliable seal of the perforations.

The technique was a preplanned approach where placement of a short section with bigger ID casing joints across possible perforated or damaged zones was included in the well program and implemented when drilling the well. After the well objectives had been achieved, the perforated zone was "sealed off" with a casing patch. The setting procedure of the selected casing patch technology was very different from that used with other expandable systems.

When running the 7″ liner string, the selected compatible liner hanger system and outside diameter (OD) of the liner wiper plugs covered both the 7-5/8″ and 7″ casing IDs. Also, cleanout tools, such as casing brush, scrapper, magnets and junk baskets, should cover the ID range. The selected patch's setting mechanisms is different, in which the steel is not pushed out with a fixed diameter metal expansion tool (cone), but is expanded using a pressure activated inflating and deflating packer, which will ensure the patch is pushed out (expanded) to seal effectively against the inside of the existing casing, irrespective of the precise casing internal diameter. This expandable steel patch allowed achieving the full bore access below the patch along with seals above and below the patch to avoid any future flow into the wellbore. Since the application was installed without performing a cement squeeze job before the patch, a significant time saving was also achieved. The idea of using the 7-5/8″ casing joints as part of the 7″ liner and setting the patch inside the bigger ID was successfully implemented; and integrity as well as full-bore access were ensured in the application.

This method and knowledge can benefit the oil and gas industry. The paper shares the entire experience obtained during designing, planning, and successfully installing a fit-for-purpose casing patch that brought value in terms of bore access and possibility of future interventions.
Planning and Execution of First Underbalanced Coiled Tubing Drilling in Adnoc´s Fields Utilizing First Successful Closed Loop System Globally
Authors: Osama Mohamed , Sumaida Ali Sulaiman Bin , Shahat Ayman El , Mutawa Ahmed Al , Almazrouei Saeed , Saleh Abdalla , Yousfi Fawad Zain , Almteiri Nama Ali , Baslaib Mohamed , Mantilla Alfonso , Deshmukh Rohit V. , Solaiman Tarek , Abdulsallam Fouad , Ladmia Abdelhak , Rangel Pedro , Rennox John , Cui Shuai , Jumagaliyev Yerlan , Basha Maged
Published: May 2023

The Operator planned and conducted Underbalanced Coiled Tubing Drilling (UBCTD), operations on 3 wells in Operator Onshore fields targeting tight sour gas carbonate reservoirs. The objectives of these operations were to evaluate the applicability of the technology in these fields, to understand requirements and methods of the technology and to evaluate the benefits of drilling the target formations in an underbalanced mode.

As a preliminary step, the Operator conducted a feasibility study that flagged potential limitations to deploying UBCTD operations in existing wells, due to limitations on the completion design and other factors. All of this resulted in the plan to drill fit-for-purpose wells to the top of the reservoir to facilitate the deployment of the technique. These wells were completed with 5.5/4.5 in. Tubing and 7 in. Liner and left with a 100ft open hole interval from where CT drilling operations would later continue. The results of the feasibility study notwithstanding, additional detailed engineering work was performed in all aspects of the design by the operations team to ensure the success of the trial, including a review and validation of the available data and the feasibility to deliver the stated objectives (lateral length, underbalanced conditions, minimal flaring operations, drilling fluid re-circulation, etc.).

As a result of this approach, all three wells were successfully drilled in underbalanced conditions and to the target lateral length of 4,000 ft. Well placement was facilitated using Biosteering techniques and continuous monitoring of the well performance vs. drilled footage, allowing steering decisions to be made in real-time to maximize the production of each lateral, resulting in outstanding production results of 3x the productivity of similar wells drilled conventionally, (after stimulation).

This paper will detail the design process highlighting key engineering decisions and assumptions taken during the design process and comparing them to the actual behavior of the well and the impact of real-life constraints on the operational parameters. The base design and lessons learned from the project will serve as a launching pad for planning and efficiency gains for future UBCTD operations.
Selection of Tool Joint Material and Connection for Drilling Tubulars in Sour Service Environments
Authors: Awad A. , Aydin M. , Hehn L. , Jaber A. Q.
Published: May 2023

The torque requirement for sour service drill pipe connections has always been a drilling challenge. Operators and contractors face challenges when selecting the appropriate tool joints to use in a sour environment, especially when combined with deeper or longer wells.

Depending on the severity of the sour service environment, which is defined by the Association for Materials Protection and Performance (AMPP) [formerly National Association of Corrosion Engineers (NACE)] MR0175-2015 severity diagram, where environmental severity is defined in regions (0, 1, 2, and 3), several studies have been carried out to understand the actual limitations of the tool joints based on each connection design and tool joint material grade and not a "one-size-fits-all" approach (Plessis, 2022). A research and development (R&D) and industrialization test campaign was started to confirm the connection technology performances and limitations in each sour service environment.

Original equipment manufacturers (OEM) provided various tool joint material grades and connections technology to address drilling engineers’ specific needs for sour service environments. For example, a drilling engineer may require an increase in the maximum torque in the connection. This led to some exotic developments in double shoulder connections (DSC) technology, with thread designs other than the API standard for rotary-shouldered connections. Depending on the sour service region for the drilling operation, newer DSCs allow additional torque without compromising the sour service resistance features. The limited availability of high strength and sour service resistance standards added pressure on OEMs to innovate new grades. The drilling engineers demanded that these grades be able to drill deeper and longer wells. In addition, they wanted to customize tool joint grades to fit into the needed drill pipe.

As the drillstem technology leader, we saw an opportunity to drive this initiative and offer a sour service resistance suitable for each region, depending on severity. This allows operators to reach the maximum limitation a tool joint can offer based on its tensile strength and connection design.
How to Comply Ai Generated Data with Wells Hse Performance Procedures and Requirement in Practice
Authors: Shirkhorshidi R. , Norazman N. , Rosli M. B. , Arriffin M. , Karbasian M.
Published: May 2023

In recent years, many companies have deployed AI-based monitoring systems to detect unsafe act and conditions on industrial setups in real time. Although such technology has proven its capability, the industry hasn't shown a rush toward its usage as what we experienced on (e.g., ChatGPT). This fact shows that using AI integration into closed circuit television (CCTV) cameras alone is not enough to maximize such technologies in industrial setups and processes despite their huge development.

An offshore drilling rig has an extremely harsh working environment, which involves people of a wide variety of professions and cultures. Therefore, any solutions that aim to mitigate risks there must engage all sectors and stockholders, be based on existing culture and comply with current procedures on rigs. This is neither an easy nor an impossible mission.

A key objective of this practice was to build an AI-based platform that would not only benefit end users in various levels and prove the technology capability, but also deliver values. Therefore, to create the most efficient AI-based platform for everyone, cutting-edge noise reduction technology, risk assessments, and technology capabilities were aligned with existing safety procedures, reporting systems, and management cultures.
Implementation of a Permanent Well Barrier Across Triple Casing 7-Inch × 9-5/8-Inch × 13-3/8-Inch Casing in Record Time for the Customer, Saving 4.4MMUSD and 17 Days of Rig Time
Authors: Khan Muhammad Zafar , Jofri Ali , Swadi Shantanu , Ali Hammry , Najmi Nik Fahusnaza
Nik
Published: May 2023

This paper discusses challenges in section milling operation for three strings of casing configuration across the cap rock, to enable a zonal isolation for a well that was drilled in year 1980. A high ratio section milling (HRSM) technology was successfully implemented to deal with this complex well that had all the casings cemented to the surface, together with centralizers for each joint to prevent a simple cut and recovery of casings. The conventional operation on the other hand would require the cutting and pulling of the inner casing, followed by casing milling of the long string of inner casing.

The new HRSM technology eliminated excessive casing milling operation which is conventionally required to access two or three strings of cemented casings prior to place a well barrier. The HRSM technology has a high expansion ratio to enter small restrictions coupled with 6-point active stabilization to counter dynamic loads and vibration when section milling. The operations challenges were optimized using the standard section mill assembly, a high ratio underreamer designed with casing scraper arms and the newly developed HRSM with new arms for the 3-string configuration.

As part of the planning phase, identifying the depths for inner and outer milling were considered along with the placement of couplings and centralizers which is crucial for milling operation. Once the window plan was completed, a thorough BHA vibrations analysis was carried out followed by a comprehensive hydraulic analysis to identify key parameters for milling and mud rheology for the entire operation.

One of the key challenges during the execution phase was the milling the centralizers on each joint of 7-inch and 9.625-inch casing. The operation was initiated by milling in the inner 7-inch casing in two stages. First the cut out of 7-inch casing was initiated followed by flush knives to mill the casing and creating a 34.7m window to access the 9.625-inch casing. A high ratio underreamer was used to clean the cement sheath in 9.625-inch casing before the new HRSM technology was run to section mill a window of 24.15 meters in 9.625-inch casing. The new HRSM was specifically designed with new cut out and flush knives to mill the 9.625-inch casing inside 13.3.75-inch casing. The final clean out of 13.375-inch casing was completed by newly designed scraper arms for the high ratio underreamer thus providing a solution of restoring the caprock across 3 strings of casing.

The unique design of HRSM technology led to the completion of first of its kind application by restoring caprock across 3 strings. This niche job has been able to save the client significant rig time for its plug land abandonment operations.
A New Mechanical Tool and Method to Accessing Casing-Casing-Annulus to Remove Compromised Cement and Injecting a New Sealant
Authors: Machocki K. , Alshaarawi A. , Alsheikh M.
Published: May 2023

This work presents experimental studies on a new tool concept to address casing-casing-annulus (CCA) pressure leak challenges in the drilling industry. The new method uses an intervention-type tool that allows for exiting the casing, cleaning cement behind, and injecting any required sealant to block fluid migration on the annular side. Addressing such CCA challenges is essential for increasing the production time and maintaining wellbore pressure integrity.

A combination of 3D modeling and experimental studies is used to evaluate the feasibility of the new concept for addressing CCA fluid migration challenges. This study focuses on the development and evaluation of a tool that allows accessing and sufficiently cleaning cement in multiple CCAs. We have successfully tested a scaled tool. This tool can punch a small hole in a casing at a unique angle and clean cement behind it by drilling spirals on the annular side.

The new method for accessing the annular side of the casing and cleaning cement behind it has been developed and successfully tested using scaled model rigs. Studies have involved an early proof of the concept in plastic and steel. We have also simulated cement with fluid communication channels behind the casing with a successful attempt of removing it.

The experimental test results are being used to further develop a robust, downhole field-deployable tool and method that captures the essential features required to access and operate in CCA areas. The current study suggests that a significant section of cement can be removed by the proposed method: One small-diameter hole is drilled in the casing, and then a cement removing assembly is run in a spiral motion on the annular side of this casing. A suitable sealant can be injected in the created void in cement to stop potential fluid migration.

This experimental study suggests that the CCA can be accessed and resealed with a minimum time and equipment if required.

This CCA milling-injection system (patent pending) utilizes a novel, easily-deployable tool. This tool enables milling access into the annular side of designated casings, and enables cleaning the cement behind it. The new system only mills one hole in the casing limiting its damage and providing the ability to clean a significant section of the cement at the desired depth. This helps address potential CCA leaks, saves time and cost.
Disruptive Plug and Abandonment Technique Using Bismuth Alloy for Offshore Operations Enhancing Sustainability
Authors: Kuyken Chris , Carragher Paul , Talapatra Didhiti
Published: May 2023

The bismuth alloy technology is capable of permanently and eternally shutting-off gas migration in single or multiple casing annuli by forming a V0 rated Metal-to-Metal gas tight seal. For P&A operations the bismuth alloy barrier technology results in a significantly higher level of sustainability compared to the current conventional way of performing P&A operations in oil and gas wells. This requires to be acknowledged in the vision for the future of P&A which will be one of the most emission intense oil and gas activities.

This paper will explain results of recent P&A campaigns that support the above fact. Bismuth alloy barriers were deployed inside 12 section milled windows of less than 50 feet length in a recent campaign for an operator in the Middle East. The wells were successfully P&A- ed, building on a track record of a worldwide P&A campaign with the "Seal Through Casing" bismuth alloy technology with about 160 wells executed between 2015 and 2023.

The reason for the eternal barriers is related to the unique and unmatched physical barrier performance properties of bismuth. Bismuth, in its molten form, which is melted downhole using the energy generated by the thermite heater, has the viscosity like that of water (1 – 3 cps) and a specific gravity of around 10. Which means it is about 10 times heavier than water. This allows it to flow freely in all directions - into section milled windows or through perforations, crack, crevice, or micro annuli displacing any fluid in its path (Fig. 1). These bismuth alloys are eutectic in nature which means one of the properties that they exhibit is they change phase at a single sharp temperature without passing a two-phase equilibrium, i.e. liquid and solid state. Another unique property of elemental bismuth and bismuth-based alloys is that it expands on solidification, like water as it solidifies into ice. In case of pure bismuth and bismuth-based alloys this volumetric expansion ranges between 1% – 3% depending on the composition of the alloy. Bismuth based alloys once molten can thus flow into any volume or annuli and take its shape and once solidified it expands against the casing, cement or formation creating a V0 gas tight barrier.

These unique physical properties combined with high corrosion resistance nature make bismuth-based alloys the ideal candidate for long term "eternal" P&A material.
Study on Anti-Corrosion Performance and Applicability of Self-Healing Coating for Tubulars in CO2 /H2S Environment
Authors: Wu Bohong , Qiu Ping , Shi Shuzhe , Zhang Yanna , Huang Xueqin , Nie Zhen
Published: May 2023

In a Middle East oilfield, reservoirs are characterized by high temperature, high salinity, high CO2 / H2S content, and low pH, which leads to harsh corrosive environment. With development of the field, the increasing water cut and application of CO2-EOR technology have made tubulars face greater corrosion risk. Therefore, employing feasible anti-corrosion coating to corresponding part is one of the most effective technologies to mitigate downhole corrosion risk, reduce workover, and avoid potential HSE risk.

Corrosion environment characteristics was thoroughly studied by reviewing production history, water chemistry, gas composition, downhole temperature and pressure, logging data, etc. Downhole corrosion condition was classified based on NACE standard RP0775-2005. Based on this, the field simulated corrosion tests were carried out on the self-healing coating in high-temperature and pressure autoclave. The self-healing coating was fabricated by loading slow-released MBT-LDH nanocomposites to the phenolic epoxy resin. For comparison, the similar experiment was also conducted on commercial phenolic epoxy coating and heavy-duty coating. The anti-corrosion performance and applicability of the coatings were characterized by SEM/EDS, FT-IR and EIS.

Two main factors have been considered while evaluating the coating options, the first consideration is reliability and durability of the coating. If the coating is easily damaged during operation and transportation, its protective performance decreases after damage, which cannot be easily repaired again. The second consideration is the compatibility of the coating in a harsh downhole environment. Considering the above aspects, the self-healing coating, commercial phenolic epoxy coating and commercial heavy-duty were selected. After corrosion tests, a small amount of corrosion products can be observed on the commercial phenolic epoxy coating surface both in the simulated well head and bottom condition. There were no obvious morphology changes on the heavy-duty coating surface in both condition, however, chemical degradation of the coating was observed in well bottom condition. Notably, the self-healing coating appeared no peeling, bubbling and other defects in both conditions. There were corrosion products identified in the pre-destructed area of the coating, which attributed to the localized inhibition of the self-healing coating.

This paper investigated the corrosion resistance coating technology, including coating selection evaluation, typical tubing thread area protection technique, coating chemical and physical property analysis and evaluation. The study also recommended coating applicability for the target reservoir. The results suggested that phenolic epoxy based self-healing coating show robust anti-corrosion performance and can be used in the downhole containing CO2 and H2S.
The Development and Application of Ultra-Short Radius Lateral Drilling Technology in Low-Permeable Reservoir of Western South China Sea
Authors: Huang Yi , Liu Hexing , Liu Zhiqin
Published: May 2023

L2 formation of X Oilfield in western South China Sea is of characteristic of low porosity, low permeability and well controlled reserves, and long well interval, drainage area and controlled reserves can be significantly increased by adopting ultra-short radial radius drilling technology. Flexible drill pipe and drill bit was used in Well WZ-X1 to perform kick-off operation with only 2.4 m footage to increase inclination from 37 °to 87 °, and hold its inclination by drilling 60-62 m alongside reservoir with trajectory control margin of ±2°. This paper highlights the trajectory control technology with research of BHA, build-up and hold drill bit, and accurate calculation. During the field operation, drilling parameters were adjusted on the basis of formation variation and outstanding trajectory effect was accomplished and ultra-short radial radius trajectory control technology was achieved. This technology can solve the problem of trajectory control and extend horizontal section of reservoir. It can increase wellbore drainage area and well control reserves, providing technical reference for future operation.
Understanding Drilling Dynamics Thru Tandem Downhole Recording Tools Enabled Drilling Performance: Middle East Specific
Authors: AlHosni Fahad , Echevarria Edgar , Ruzhnikov Alexey , Rojas Luis
Published: May 2023

Drilling the 12.25-in. landing section in one of the Middle East fields had been a challenge in terms of drilling performance due to combined downhole severe drilling dynamic mechanics effects and borehole instabilities. These complications eventually lead to downhole tool failures and a low rate of penetration (ROP). This manuscript describes the solution to introduce tandem downhole dynamic recording tools in the Bottom Hole Assembly (BHA) which provides a better understanding of the downhole dynamics and mechanics effects guiding to optimum BHA design and leading to better performance.

Drilling the curve and landing section is challenging due to extreme stick & slip (S&S) and shocks & vibrations (S&V) phenomena resulting in low performance and difficulties in achieving the directional requirement. The 12.25-in. landing section is drilled with a full set of Rotary Steerable System (RSS) drive, Positive Displacement Mud Motor (PDM), Measurement While Drilling (MWD) and Logging While Drilling (LWD) tools, making the BHA very rigid. Nevertheless, many initiatives have been carried out to enhance the BHA and bit design with limited improvement. After performing a detailed risk analysis, tandem downhole dynamic recording tools were introduced to understand the downhole dynamics behavior and the interaction between the bit, the drilling BHA components, and the different formations drilled.

The downhole dynamic recording tool is powered by batteries and records the data in memory mode for post-run analysis. It measures downhole drilling mechanics with its three-axis accelerometers, gyro, and temperature electronics along with other measurements. The downhole recording tools was installed tandemly across the 12.25-in. motorized RSS BHA where one tool was positioned inside the bit and another one in a sub above the mud motor. After the run, all the data from the two downhole recording tools were downloaded and then analyzed. From the recording tool at the bit, it can be concluded that the PDC bit used in the analyzed run, generated low-to-medium stick & slip, hence, a new bit design with more aggressive features could be used safely to enhance the ROP. From the recording tool in the sub above the mud motor, it was concluded that the BHA components and mainly the LWD tool created high-to-severe stick & slip due to its stabilizers, and action should be taken to minimize this effect. In addition, the drilling fluid lubricity needs to be enhanced to reduce the stick & slip and shocks & vibrations effects on the tools. All the presented solutions and lessons learned of the downhole dynamic recording tools utilization can be used for future run enhancement and to be replicated worldwide as applicable.
Resolving Critical Build-Up Section Challenges in a Major Oilfield in the Middle East Using Enhanced Oil-Based Mud Solution
Authors: Elmohandes M. A. , Algaiar M. M. , Farahat M. Y.
Published: May 2023

Drilling mixed lithology formations of Shales, soft/hard Carbonates, and long Anhydrite intervals in a single section that comprises directional drilling from vertical to well landing with elevated mud weights and high overbalance represents numerous challenges including wellbore stability, tight hole, formation ledges, differential sticking, high torsional and lateral vibration levels, erratic drilling torque, poor rate of penetration, and failure to run the 7" liner to bottom. Controlling such formations with water-based mud system is difficult, even with large percentage of water-based lubricant, thus leading to multiple downhole tools failures and failing to drill this challenging section in one run.

Due to the fact that drilling this section falls under a lumpsum turnkey project and the section performance and cost are crucial to the well delivery, the drilling engineering and drilling fluids teams worked together to address the section challenges by replacing the water-based mud system with a customized oil-based mud system. All associated risks for this replacement including the spill control measures and environmental hazards were discussed and presented in a risk assessment form.

Wireline and logging-while-drilling formation characteristics logs in different field locations, offsets drilling performance, stuck pipe incidents, and tripability data were gathered and a rigorous lab testing was performed to formulate an efficient oil-based mud formulation with optimum bridging design to control the formation challenges whilst maintaining a competitive system cost compared to the previous water-based mud system.

The optimized bridging materials design in accordance with the very low lubricity coefficient of the oil-based mud system helped strengthening the weak formations, reduced the stuck pipe risks and intensely minimized the drilling vibrations thus helped in applying full drilling parameters, improved the rate of penetration well after well, and delivered the section in one run without downhole tools failure. In addition, the controlled filtration showed exceptional tripability compared to the old mud system and saved more than 8 hours to pull the directional assembly back to surface. The 7" liner was run smoothly to the planned depth with an improved section delivery time and operational costs.
Using Game Theory Algorithm to Identify Critical Watersheds based on Environmental Flow Components and Hydrological Indicators
Authors: Khiavi Ali Nasiri , Mostafazadeh Raoof , Talouki Fatemeh Ghanbari
Published: May 2023

Improper use of water resources has caused significant changes in Natural River Flow (NRF), which indicates the need to assess changes in Hydrological Indicators (HI) and Environmental Flow Components (EFC). Therefore, the present study was conducted to identify critical watersheds using HI and EFC under the influence of the dam and without the impact of the dam using the Borda Scoring Algorithm (BSA) based on Game Theory (GT) in Nir-Chay, Balkhlou-Chay and Qareh-Sou Rivers as consequent stations in northern Iran. Indicators of Hydrological Alteration (IHA) software was used to quantify river flow indices. 26 HI and 21 EFC have been quantified and were used to identify critical watersheds. Principal Component Analysis (PCA) was used to determine the most significant indicators. After the data reduction, the initial matrix and comparative preferences of Game Theory (GT) were used, and the scores were assigned to watersheds based on Borda Scoring Algorithm (BSA). Based on the results, it can be said that in the Doost-Beiglou watershed, the small flood peak in the pre-dam period was 14.08, which was reduced to 3.5 in the post-dam period. The scoring of the studied watersheds based on HI and EFC GT theory showed that the watersheds affected by the dam with the scores of 216 and 174 were ranked first and were selected as the most critical watersheds in the study area. As a concluding remark, in the watersheds of Pol-e-Almas and Doost-Beiglou, which were affected by Yamchi and Sabalan dams, significant changes were observed in HI and EFCs. Therefore, in terms of NRF, Balkhlou-Chay and Qareh-Sou Rivers were categorized as critical conditions, which highlights the importance of these watersheds for managers and decision-makers in making optimal decisions.
Development of TTGO Wireless Microcontroller Based Smart SpO2 Band for the In-Time Diagnosis of the COVID’19 Infected Patients
Authors: Chowdhry Bhawani Shankar , Mouzam Salman Ul , Shah Ali Akbar , Mirza Ghulam Fiza , Uqaili Mohammad Aslam
Published: May 2023

Due to rapid rise in COVID’19 the death toll exceeded 30,000. The majority of these fatalities were brought on by the disease’s tardy diagnosis. Mostly, people who live in poverty today are still unaware of all of its signs. In order to help them, a Smart SpO2 sensor based wrist band has been developed in collaboration with UNICEF, the School of Leadership Foundation, and the National Center of Robotics and Automation - Human Haptics Robotics Condition Monitoring Lab - MUET. It uses a TTGO Wireless Microcontroller Unit and an Sp02 sensor to help determine a person’s oxygen saturation and heart rate. The wristband is made in such a way that it is integrated with the COVID-Sahara App, an app that notifies the patient’s neighboring hospital or monitoring person if his oxygen saturation limit drops below the prescribed level. With the assistance of 21 afflicted patients and health professionals at a private hospital in Hyderabad, the band has undergone testing. With an accuracy of 95.238 percent, the band has demonstrated its remarkable versatility by correctly diagnosing 20 out of 21 patients.