bluuebunny/crossref_metadata_2025_split huggingface dataset:
Salinity and Temperature Effects on Oily Produced Water Treatment Using Polyaluminium Chloride
Authors: Xu Limin , Han Ming , AlGhunaimi Fahd , Bataweel Mohammed 
Published: March 2023

Abstract
Polyaluminium chlorides (PAC) has replaced a large part of traditional aluminous coagulants for water treatment in recent years because of low dosage, high efficiency, low cost and convenient usage. This work studied the effects of salinity and temperature on the efficiency of PAC in removing oil and colloids from oily produced water (PW) and the potential of PAC for high salinity PW treatment.
Minghua produced water (Di-MHPW) with salinity of 2,815 mg/L and high salinity produced water (HSPW) with salinity of 102,290 mg/L were used in this work. The efficiency of PAC and the optimal dosage were investigated by stability analyzer which allows a step-by-step vertical scanning of the dispersions. The separation time, floc volume and water quality after treatment could be obtained by stability analyzer.
Transmission intensity was used to evaluate the oil-water separation in PW. High transmission intensity indicates low oil content. Without PAC, HSPW presented faster increase in transmission than low salinity PW indicating poorer stability. The zeta potential of oil drops and colloids in low salinity PW (2,815 mg/L) was −20.4mV. High salinity (102,290 mg/L) increased the zeta potential to −2.2mV, which makes the oil-in-water (O/W) emulsion unstable than low salinity PW. With the addition of PAC, HSPW results in slightly lower transmission with less floc volume. This could be explained by the floc size after the addition of PAC in two PWs. The size of formed floc in HSPW was much smaller than that in MHPW leading to slower separation of floc from aqueous phase and lower transmission intensity. Increasing the temperature enhanced the PAC efficiency in removing oil and suspended solids in both high and low salinity PWs. However, the floc volume also increased especially in Di-MHPW resulting in less water volume. In HSPW, the temperature effect on floc volume was not obvious. Though high salinity reduces the performance of PAC in water treatment, it is still an efficient flocculant for HSPW treatment with high flocculation efficiency, small floc volume and short separation time.
This work provides the insight of oily produced water treatment using PAC and the effect of salinity and temperature. The results are helpful to develop novel flocculants used for high salinity produced water treatment.
Review of Electrical Motor Technologies for ESP Applications
Authors: Wrighton Chris , Vlad Rusu Alexandru , Lacchetti Matteo , Smith Alexander 
Published: March 2023

Abstract
The electrical submersible pump (ESP) is a key artificial lift enabler within the oil industry. Since their launch in late 1920s, induction motors have been the main motor technology used in ESPs. Recent advancements in technology have opened opportunities for the development of higher performance and more efficient topologies for electrical machines. This paper aims to provide a review of different motor technologies in the well oil and water fluid lifting industry.
The analysis in this paper is constructed around a comparison between several electrical machine technologies when exposed to the harsh downhole environment. The dimensions of each machine are similar and provide a fair comparison. The advantages and drawbacks of each motor are presented in respect to key mechanical or electrical considerations. Solutions are recommended when there is evidence from previous work, and several questions are raised for the feasibility of certain topologies in respect to the new challenges.
Results show why the induction machine (IM) was selected by ESP providers in late 1920s and why it still has value nearly 100 years later. Permanent magnet machines (PMMs) offer higher power density levels in a smaller package. Synchronous reluctance motors (SyncR) offer a more robust and cheaper alternative, but the design is relatively new and further analysis is still required. Advancements in switched reluctance machines (SRMs) allows for the development of a motor with IM torque capabilities. Both SRM and BLDC (brushless DC) require pulse width modulation (PWM) square-pulse drives, which may prove to be a challenge when driven over a long cable. This paper emphasises the importance of a proper analysis of each motor technology in respect to a particular application. The design of electrical machines should be tailored around the specification of each environment to provide a more robust and efficient system.
Although some literature is available on the comparison of PMM and IM in the artificial lift (AL) industry, it seems to promote PMMs with little attempt to suggest improvements for traditional IM topologies, which still offer many benefits in terms of ease of manufacture, robustness and capability to operate in extreme environments such as with high temperatures. This paper discusses several other technologies that have not previously been considered. The aim of the paper is to provide a holistic view of the possible problems each technology will face in the downhole environment and inform future work on possible design improvements for the most promising technologies. In addition, the paper will provide a comparative assessment of the different motor technologies in terms of their strength and weaknesses, and also issues that should be addressed for ESP applications.
Starter Wellhead: Achieving Mechanical Barrier Isolation in Large Casings Annuli While Countering Wellhead Thermal Growth
Authors: Mukhlifi Mohammed Eid , Wirawan Pandu , Alamer Mansour Abdullah 
Published: March 2023

Abstract
This paper describes the method and apparatus of the Low-Pressure Starter Wellhead System used for 36" and 30" conductor casings to provide the required wellhead sealing integrity for surface formations that have the potential to release formation fluids to environment during the well life cycle without restricting the casing thermal growth. The current industry approach is to rely on cement as the only barrier for casings annuli larger than 24" to seal off shallow hydrocarbon formations without any consideration for thermal growth resulting from well production.
Cement, the current barrier for surface casings (greater than 24" size), is prone to failure due to cracks resulted from the wellhead thermal growth as well as cement placement challenges. Therefore, this necessitates mechanical means of preventing hydrocarbon or water release to atmosphere via proper and sustainable solutions. This will provide the required support to prevent any negative impact on the environment, risks to personnel and to assets. Risks will be higher if the well is close to residential/ populated area and/or located in offshore environment.
The Low-Pressure Starter Wellhead System is new design concept in oil and gas industry (Patent Number: US11396785B2) as currently there are no available technologies to provide mechanical sealing for big surface casings while encountering thermal growth. It will provide a complete solution to isolate surface zones, provide seal and load integrity and cater for the casing thermal growth during the well production lifecycle. The new design, also, will facilitate the drilling operations while maintaining the well control capability at all times.
The benefits of the new device are significant. Achieving mechanical isolation for big casing sizes greatly enhances well integrity, especially for wells with shallow hydrocarbon or water formations. Accommodating for wellhead thermal expansion due to high well temperature provides a redundancy and eliminates the associated challenges with cement failures and formation fluid release to the atmosphere. This results in substantial cost avoidance, safety improvement and better environmental protection.
Sealing potential problematic surface formations is paramount for any well integrity considering the current industry gap with these large conductor sizes. This system presents a unique design in the oil and gas industry to establish a mechanical barrier for larger casings while accommodating for wellhead thermal growth.
Well Integrity Challenges while Drilling in High Pressure and Narrow Window Environment: A Case Study of a Deep Gas Field in the Middle East
Authors: Ovwigho Efe Mulumba , Almomen Mohammed Sami , Corona Mauricio , Terrez Jose 
Published: March 2023

Abstract
While drilling the 12" section, a water bearing formation is encountered prior to reaching the target gas reservoir formation. This formation is sporadically-charged across the field requiring a KMW up to 21 ppg. This poses major well integrity challenges as it becomes critical to avoid losses in the resulting narrow mud window and ensuring proper cement placement. Inability to predict the mud window makes it impossible to define the drilling strategy to implement.
To understand the drilling challenges, in-depth offset wells analysis was performed. Based on mud weights required to drill across the reference formation, the heat-map for historical KMW was created based on confirmed well control events. It was difficult to predict formation-flow potential. Field geomechanics studies were then carried out to correlate the mapping done earlier. Once possibility of encountering abnormally pressured formation is flagged, in order prevent drilling risks such as loss circulation and poor cementing placement, proactive measures such as: Improved influx monitoring, drilling/cementing fluids optimization, liner-and-tieback system implementation, Managed Pressure Drilling/Cementing, optimized casing design were put in place.
The integrated approach led to quick influx detection, proper definition of mud window, i.e. Pore Pressure and Fracture Gradient together, helped to prevent the losses, design of fit-for-purpose bridging strategy to ensure full drilling fluid column at all time while avoiding the cost associated with fluid losses. Drilling the section with Managed Pressure Drilling system (MPD) and low mud weight led to achievement of high ROP leading to substantial time saving. The Liner string was run and Managed Pressure Cementing (MPC) was implemented to manage the equivalent circulating density (ECD), avoid losses and ensure good zonal isolation. Overall non-productive time was reduced by 40% as compared to the offset wells in the area.
Integrated drilling approach delivers great gains when there is good understanding of the well integrity challenges and solutions are tailored to solve identified problems.
Polymeric Water Based DIF (Drill-in Fluid) Improved Design to Stabilize Complex Wellbores
Authors: Chinea Gonzalo , Moroni Luigi , Shujath Ali Syed , Kaageson-Loe Nils 
Published: March 2023

Abstract
The design of a drill-in fluid (DIF) requires an in depth understanding of the reservoir formation characteristics in order to minimize production impairment through processes such as fines migration and clay swelling. This is a, relatively, well understood design process for simple homogenous reservoirs. More complex wells, where shales are exposed in the reservoir section or reservoirs are depleted, may require additional products to maintain wellbore stability and allow the well to be completed. This paper assesses the impact on formation damage from the addition of these wellbore strengthening products.
Polymeric water based DIFs contain calcium carbonate bridging particles which can be dissolved with acid, and biopolymers which can be degraded with enzymes. Products used for wellbore strengthening usually include graphitic materials, which are neither acid soluble nor degradable by enzymes. This study evaluated the effect of these addition materials in combination with calcium carbonate through a series of Return Permeability tests to determine their effect on sandstone formations. Return Permeability tests were performed to simulate well operations in a laboratory environment, during which the measure of relative permeability is used to quantify any change in permeability caused when a fluid is applied to a rock sample. For comparison purposes, baseline tests with standard polymeric water based DIFs were initially performed. Subsequently, different additives were incorporated in each system to evaluate their effect on the return permeability.
This paper presents the results of an extensive study investigating the effect on return permeability from the addition of graphitic and polymer materials used for wellbore strengthening, using two polymeric water based DIFs. The results show that, under the correct conditions, the addition of these products to the fluid formulation for the enhancement of wellbore stability does not significantly impair the permeability of the formation as had previously been believed.
Executing the Digital Well Plan - Enhancing Process Automation
Authors: Hummes Olof , Macpherson John D. , Bone Kimberley , Marwah Gaurav , Arévalo Pedro , Forshaw Matthew 
Published: March 2023

Abstract
Automation of well construction combines process and machine automation to deliver cost savings and efficiency gains, alongside safer operations and faster collaborative decision making. Integration of well planning and execution improves performance, minimizes risk, and creates the framework for batch control of well construction. Generating intuitive and standardized insights from historical and live data streams enables reducing uncertainty and driving technical limit performance at every stage, for the safest and most economical well delivery possible.
Remote operations have become standard practice in well construction and drilling automation is rapidly growing. Machine-learning based models can predict hazards and best operating parameters. The paper describes how these elements are combined to easily analyze offset well data from multiple sources for performance benchmarking, deep technical analysis, and risk management. Integration with physics-based models (the digital-twin) establishes a coherent execution roadmap, a real-time digital recipe that is directly used in rigsite automation. During execution, model assumptions are replaced by live sensor data. Those models are then re-calculated in real-time for automated process control and become available for future planning.
The viability of integrated well planning and automation systems is no longer disputed, and industry focus has shifted towards proving the potential of this approach. Pertinent case examples from drilling operations are examined in the paper, including optimizing performance through harnessing analytics of large data sets from offset wells, and on exploring the integration of AI techniques for risk prediction and mitigation. The insights gained, coupled with the digital well plan, are instrumental for optimization and automation of tripping equipment in and out of hole, and of drilling ahead operations.
Integrating the digital well plan with "lessons learned" from the analysis of all available data and using a digital-twin concept with physics-based and data driven models, provides the foundation for the next step in process automation: the creation of digital procedures for process automation of well construction. This capability extends the cost savings and efficiency gains realized in recent years through remote operations.
Prediction of Slug Length for High Pressure Gas/Liquid Two-Phase Flow in Horizontal and Slightly Inclined Pipes
Authors: Al-Safran Eissa , Aql Ahmed 
Published: March 2023

Abstract
Slug flow in pipelines is the most common flow pattern. Slug length is crucial characteristic for pipeline and downstream separation facility design and operation. In addition, mechanistic two- phase flow models require slug length as closure relationship to solve for pressure gradient and average liquid holdup in slug flow. However, the existing slug length closure relationships developed for low pressure are found to poorly perform in high-pressure conditions, i.e. high gas- to-liquid density ratio high, resulting in high uncertainty predictions of slug length, pressure gradient and liquid holdup. This work aims to propose a mechanistic slug length model and to identify the optimal closure relationship for high-pressure condition through error minimization technique using Genetic Algorithm. In addition, the identified set of closure relationships are found to match the physics of slug flow under the investigated conditions. As a result, the proposed model result in a coefficient of determination R2 = 0.85 and an Absolute Average Error (AAE) approximately equals 70% outperforming the best-performing exiting model in the literature.
Heavy Duty Robotic Fishing Allowed to Restore Injectivity in Critical Well – A Case Study
Authors: Nobile Blanco Juan Jose , Prabhakaran Sudesh , Shiwan Shiwanshu , Rout Amitav , Ting David 
Published: March 2023

Abstract
An offshore injection well was out of operation after unsuccessful wellhead maintenance operation, when a slickline Bottom Hole Assembly (BHA) was stuck inside Subsurface Safety Valve (SSSV). Several fishing attempts with variety of technologies were unsuccessful. Heavy Duty robotic fishing tools were used to retrieve the fish (acid syringe and soak sleeve along with slickline assembly) from SSSV, restore injection, and provide well integrity.
Analysis of unsuccessful fishing attempts suggested that the main reason for failures to achieve the goal was inability to provide sufficient force in controlled manner (without jarring), while there were no issues to latch the top of fish. Robotic fishing tool consisting of stroker tool with 100,000-lbf force available, reinforced with precise force and piston position control, in tandem with heavy duty overshot was proposed for operation. An onshore test, replicating the downhole scenario, was performed during the preparation phase to prove the concept and evaluate the functionality of the tools.
Fishing operation proven itself complicated - after successful latch and applied overpull, the fish started to move up for limited distance as long as stable upward force was applied. Series of strokes within same run were not able to completely free the tool, so the fishing tool was disconnected from the fish and pulled to surface to be replaced with fresh one. The real-time readout and achieved progress suggested that fishing strategy was adequate, and more runs were required in same configuration. Total four runs with numerous strokes were required to unstuck fish completely so it could be pulled to surface by strength of e-line cable. After retrieving the complete fish, it was possible to perform a successful inflow test to confirm SSSV being operational and put the well back on injection in a reasonable amount of time.
First Time Ever Rigless Securement of Offshore Gas Well with Deep Plug Prior Workover
Authors: Mata Gilberto , Aghazada Kamal , Alghrairy Mohammad 
Published: March 2023

Abstract
A proper deep isolation of high-pressure sour gas reservoirs through Corrosion Resistance Alloy (CRA) tubing had been a real challenge for offshore gas operations owing to the inherent limitations present in all rigless operations needed to accomplish this task. Moreover, the presence of high shut-in gas pressures is a major challenge to perform wireline operations needed to run and set the desired flow-barrier plug. Finding a suitable operational procedure, sourcing the adequate tools, performing a well-coordinated operation in a short period of time were the key factors identified to deliver a recently field-proven solution to properly secure and isolate an offshore gas well affected by gas passage through control line due to leaking piston seal of Tubing Retrievable Sub-Surface Safety Valve (TRSSSV).
This paper systematically describes the first ever successful operational approach implemented rigless to set a deep flow-barrier plug on wireline across CRA tubing to safely bleed-off all gas recorded passing through the TRSSSV's control line. This marked a milestone for rigless operations for the operator in their effort to secure problematic gas wells for workover in offshore operations.
Managing Wellbore Stability Challenges for an Optimum Well Delivery; Case Study, Balsam Field, Nile Delta, Egypt
Authors: El Sherbeny Wael , Baghdady Ashraf , Farag Ali , Vossen Johannes 
Published: March 2023

Abstract
This paper presents the integration of Geosciences data for three wells which encountered drilling challenges such as differential and mechanical sticking due to geological complexities. It demonstrates the benefits of integrating all available geoscience data in detecting the drilling hazards, delineating the troublesome zones, and offering a complete solution, including drilling best practices and drilling fluids design based on Geological, Sedimentological, Geomechanical and Petrophysical data analysis.
A drilling risk assessment was conducted through an analysis of daily drilling reports for the three wells in the field, meanwhile a Post-drill Geomechanical model was constructed for the same wells using all available data.
A Petrophysical analysis of the same wells was completed using wireline data to define the major parameters related to drilling risks such as porosity, permeability, facies changes, formation water salinity and shale volume.
A Sedimentological analysis utilized the available information from mud logs, image logs, and core data and cuttings descriptions, to correlate drilling risks with certain lithofacies.
This case study considers with the geomechanical model of three wells, including their drilling history, stress/pore pressure models, and rock properties. Additional highlights from the image logs are featured, showing anisotropic bedding plane failure, as well as a comparison of the images to the geomechanical model.
This case study concludes the risk and a proposed mitigation strategies that could be implemented to limit the risks posed by high overbalance, clay mineralogy, weak bedding planes and permeable sand layers and to minimize instability when drilling vertical and laterals holes in in this area or similarly complex areas.
The pressure surveys revealed the presence of both hydrocarbon and water bearing zones. The pressure gradient was 0.14 psi/ft within the hydrocarbon pay zones, whereas a 0.44 psi/ft pressure gradient confirmed the water bearing zones. The same formation pressure data was utilized to calibrate the pore pressure calculations used for the geomechanical model.
All Sedimentological and Petrophysical analyses, along with the post-drill Geomechanical analysis, were utilized to define final solutions for optimum well delivery during drilling, completion, and stimulation Phases.
Utilizing the analytics of integrated geoscience data such as sedimentology and petrophysics information, along with geomechanical modeling, can help in understanding the subsurface challenges and propose optimal solutions for optimum well delivery avoiding severe tight spots, differential sticking and pack off, in additions of minimizing the formation damages.