bluuebunny/crossref_metadata_2025_split huggingface dataset:
Introducing New 22" PDC Bit for Drilling Complex Shallow Sections in a Giant Field in the Middle East
Authors: Franco Nata Miranda , Javay Alexandre Jean Robert , Al Moselhy Mohamed Essam Abdelmoneim , ElAssy Mahmoud Mohamed Osama Mohamed Saeifeldin 
Published: December 2021

Abstract
Drilling a 22" section across interbedded, high-impact, and abrasive formations has historically been challenging in giant fields in the Middle East. The section typically ranges from 3,000 ft to 4,000 ft long and requires three to four runs to reach the casing point with conventional TCI bits. This paper covers the introduction of a new 22" PDC bit design run on rotary assembly, which has spectacularly improved the drilling performance over the conventional tricone bits.
The introduction of this new 22" PDC bit design followed a comprehensive engineering approach. Starting with the simulation of rock properties such as compressive strength, abrasiveness, and impact, a fit-for-purpose bit design was manufactured to address the needed cutting structure, number of blades, and depth of cut for the section. The downhole drilling dynamics were also thoroughly analyzed, and the bottom hole assembly configuration was revisited to match up with the new bit structure. Within the dedicated continuous improvement workflow set by the service company, the bit pattern was further optimized after the initial field trials.
After an in-depth analysis of the various formation properties and their impact on bit life, the 22" section was divided into two target runs. The upper part has high-impact and interbedded layers, and the lower part has high abrasiveness and formation compressive strength. In the upper part, the TCI bits had previously shown relatively good performance with acceptable ROP, while the PDC bits experienced damage to their cutting structure. As the impacts were lower in the bottom part, the PDC bit design was selected for the second run to the casing point, which resulted in significantly higher ROP and a longer lifetime than the TCI runs. The 2-bit strategy, spudding the section with the TCI bit and completing it with the PDC bit on rotary assembly, translated into a significant improvement of ROP by 32%. In addition to saving rig time, the overall number of bit runs was reduced by 29%, resulting in cost savings by using fewer bits. Drilling the section in two runs has now become the norm, and this winning strategy was adopted as the new standard for drilling the 22" hole section.
The introduction of the 22" PDC bit on rotary drive returned excellent results and record-breaking ROP performance. While the 22" PDC cost might seem prohibitive, the substantial rig time savings proved this solution to be very economical. Further development of this initiative to other basins in the Middle East or elsewhere will mutually benefit both the operator and service company.
Artificial Intelligence for Infill Well Placement and Design Optimization in Multi-layered/stacked Reservoirs Under Subsurface Uncertainty
Authors: Su Shi , Schulze-Riegert Ralf , Mustapha Hussein , Lang Philipp , Kada Kloucha Chakib 
Published: December 2021

Abstract
Effective well placement and design planning accounts for subsurface uncertainties to estimate production and economic outcomes. Reservoir modelling and simulation workflows build on ensemble approaches to manage uncertainties for production forecasting. Ensemble generation and interpretation requires a higher degree of automation analytics and artificial intelligence for fast value extraction and decision support. This work develops practical intelligent workflow steps for a robust infill well placement and design scenario in multi-layered/stacked reservoirs under uncertainty.
Potential well targets are classified by an opportunity index defined by a combination of rock and hydrocarbon flow properties as well as connected volumes above a minimum economic volume. Unsupervised learning techniques are applied to automate the search for alternative target areas, so-called hotspot regions. Supervised machine/learning models are used to predict infill well performance based on simulated and/or past production experience. A stochastic evaluation including all ensemble cases is used to capture uncertainty. Vertical, deviated, horizontal and multilateral wells are proposed to optimally target single or connect to multiple hotspot regions under technical and economic constraints.
A structured workflow design is applied to a multi-layered/stacked reservoir model. Subsurface uncertainties are described and captured by multiple model realizations, which are constrained in areas of historical wells. An infill well program for a multi-layered/stacked reservoir is defined for incremental production increase under economic constraints.
This work shows how robust well location and design builds on the full ensemble of cases with a high degree of automation using analytics and machine-learning techniques. Both production and economic targets are calculated and compared to a reference case for robust solution verification and probability of success.
In conclusion, an overall reservoir-driven field development strategy is required for efficient execution. However, automation is well applicable to repetitive workflow steps which includes hotspot search in an ensemble of validated reservoir models.
This work presents an integrated, intelligent solution for informed decision making on infill drilling locations and refined well design. Higher degree of automation with embedded intelligence are discussed from case generation to hotspot identification. Aspects of model calibration in a producing field environment are addressed.
Thinking Different Approach to Optimize Your Treaters
Authors: Singh Anand Kumar , Alobeidli Aysha , Bakthavachsalam Venugopal 
Published: December 2021

Abstract
Natural gas coming from the well contains hydrocarbons, CO2, H2S, and water together with many other impurities. Molecular sieve treatment of the gas is required to make it suitable for the various applications. The several process and parameters considerations contribute to the reliable and optimized operation of molecular sieve natural gas treaters.
The journey of this molecular sieve treater optimization commenced by conducting a thorough systematic study of all existing treater performance by considering various operating critical parameter. The technical feasibility studies were completed covering all the aspects like evaluating current performance of treater, conducting simulation for future capacity, licensor endorsement, conducting breakthrough test. Finally, study outcomes were implemented through management change process.
The main benefits of optimization of molecular sieve treater process are to extend the service life of molecular sieve which enable us to increase the turnaround cycle of NGL trains. Significant reduction in CAPEX and OPEX cost were realized by reducing new fresh molecular sieve procurement, reducing disposal of molecular sieve waste material and expense of shutdown, achieving 100% HSE.
This paper presents the typical operation issues and challenges in molecular sieve treatment process, best practices adopted for maximizing of existing assets considering the current and design scenarios, and performance improvement, which result to extend molecular sieve life, increase of NGL shutdown cycle and flaring reduction in trains.
Effect of Nanocellulose in Cement Systems
Authors: Kumar Animesh , Bhaisora Devesh , Dange Mikhil 
Published: December 2021

Abstract
Cellulose, the one of the most abundant biomaterials available in nature, is a polymer with cellobiose as the smallest repeating unit, with a degree of polymerization that can go up to 1000 for wood cellulose. The strength-to-weight ratio of nanocellulose is eight times greater than steel (Patchiya Phanthong et al). Nanocellulose in suspension (NCS) at a varied concentration helps increase properties of cement without changing the density of the cement slurry. Being mindful of challenges in oil and gas wells, efforts were made to enhance cement properties using nanocellulose within conventional and water-extended cement systems.
Samples of 15.8-ppg conventional and 12 ppg water-extended cements were prepared by varying the proportion of nanocellulose within an aqueous suspension. Rheology, sedimentation, compressive strength and mechanical properties were analyzed for a conventional 15.8-ppg cement system with varying NCS proportions of 0, 2, 4, and 5% by weight of cement (BWOC). Similar work was performed for a 12 ppg water-extended cement system by varying NCS differently in proportions of 0, 5, 10, and 20% BWOC.
Two-inch cubes were set at 170°F for 24 hours for each sample. They were crushed using hydraulic crush compressive strength equipment, and the force used to break the sample was recorded. Compressive strength for this cement system was measured to be 2450, 3250, 3450, and 3875 psi, respectively, for samples with 0, 2, 4, and 5% BWOC concentrations of NCS. An increase in the strength of cement with an increase in NCS percentage was observed for the 15.8-ppg slurry design, which may be attributed to the size and shape of the NCS. However, similar study carried out with 12 ppg water extended slurries showed decrease in overall compressive strength. Nano-sized particles fill the pores within the sample, impacting structural network development. Additionally, cellulose, having a fiber-like structure, may provide inter-particulate reinforcement.
Based on the results of the 15.8-ppg cement system and the high tensile strength of nanocellulose, it can be determined that NCS has a positive effect for increasing mechanical properties. By applying nanocellulose, a tailored cement system (dependable barrier) can be designed to minimize risk and maximize production from oil and gas wells.
Nanocellulose is of increasing interest for a range of applications relevant to the fields of material science and biomedical engineering because of its renewable nature, anisotropic shape, excellent mechanical properties, good biocompatibility, tailorable surface chemistry, and interesting optical properties. Low-volume NCS additions can alter the structure of the cured cement system and increase its mechanical properties. This reinforcing mechanism may provide a new opportunity for achieving higher strength cementitious materials.
Integrated Geomechanical Operations for Successful Field Development: A Case Study from Western Offshore, India
Authors: Bagga Pawandeep , Kidambi Tapan , Sharma Ashish , Panchakarla Anjana , Kulkarni Aditee 
Published: December 2021

Abstract
This paper deals with the field development study for an offshore field in the western part of India. The main points of focus are holistic execution of integrated workflows for the delivery of subsea oil and gas wells from a jack up platform in this region. Given that the encountered formations encountered in wells posed significant challenges during the drilling phase, a field level geomechanics study was commissioned to understand and mitigate any challenges and effect smooth drilling and logging operations. Understanding the geomechanical effects by analysing the offset wells drilled in the region provided significant insights into the potential challenges faced while exploring target formations.
The proposed well locations were drilled in a structurally complex geological setting. From the analysis of previously drilled wells in the region, it was evident that the variation in insitu properties of the lithologies and the extreme heterogeneity and vugular nature of the encountered carbonates caused significant drillability issues with subsequent losses, excessive cuttings, and several back reaming cycles impacting rig time and leading to generally poor borehole conditions. On the other hand, the shales encountered at shallower depths presented a different challenge, especially with a high swelling tendency, adding to progressively worsening hole conditions and significant fluid invasion. Finally, the basal clastics and the depleted zones with variable rock strengths added to the borehole instability issues, with particular zones projecting losses while others showed influxes.
In light of such a plethora of issues, an integrated approach including dynamic real time monitoring of operations, structured LWD and wireline logging programmes, a high level petrophysics, formation evaluation and borehole acoustics for shear radial profiling was carried out. A fit for purpose geomechanical model was built encompassing the results of these analyses and was continually updated in real time during the operations phase. Given the variability in the pressures, temperatures and operational mud weights in each section, execution for successful delivery of the wells was further aided by identification of the optimal mud systems, critical casing setting depths and real time drilling optimization, ensuring good borehole quality throughout for further logging and testing programmes.
The New Technological Frontiers of CO2 and Hydrogen Transportation Via Pipelines
Authors: Arcangeletti Giorgio , Scarsciafratte Daniele , Leporini Mariella , Orselli Benedetto , Santicchia Angelo , Torselletti Enrico , Aloigi Elvira 
Published: December 2021

Abstract
COVID-19 pandemic is accelerating the transition to decarbonized energy systems. In this context, major Operators and Contractors are bound to promote innovation and technological development. The paper describes how this is being applied to the design of offshore pipelines that are now required to transport not only Hydrocarbons but also anthropogenic CO2 and low-carbon Hydrogen. In order to evaluate all the new technical challenges presented in designing CO2 and H2 pipelines, a state of art has been carried out and is here presented focusing on all the new technical aspects associated to the main disciplines involved in the pipeline network design. Different technical aspects (such as performances evaluation of Equation of State in CCS, Design Standards application to both CO2 and hydrogen pipelines, energy capacity of hydrogen pipelines and others) have been also analytically or numerically addressed simulating credible pipeline operating scenarios. To achieve that, an intensive engineering effort is being dedicated to the development of knowledge, engineering tools, methods and procedures that will be the basis for the execution of future projects concerning H2 and CO2 transportation and storage. A particular focus has been dedicated to offshore pipeline design both for new installation and repurposing of existing ones. In parallel, the cooperation started between Operators, Contractors, Manufacturers, Institutions and Universities, as described in the present paper, acts as a "booster" for the consolidation of knowledge and for the advancing of technology to put in place to overcome those new challenges. Recommendations are made in relation to the gaps found in experimental evidence present in literature and gaps in Standards coverage for the proper pipeline design in those new scenarios.
Machine Learning as a Silent Observer of Advanced Geoscience Interpretation
Authors: Sajid Muhammad 
Published: December 2021

Abstract
Machine learning is proving its successes in all fields of life including medical, automotive, planning, engineering, etc. In the world of geoscience, ML showed impressive results in seismic fault interpretation, advance seismic attributes analysis, facies classification, and geobodies extraction such as channels, carbonates, and salt, etc. One of the challenges faced in geoscience is the availability of label data which is one of the most time-consuming requirements in supervised deep learning. In this paper, an advanced learning approach is proposed for geoscience where the machine observes the seismic interpretation activities and learns simultaneously as the interpretation progresses. Initial testing showed that through the proposed method along with transfer learning, machine learning performance is highly effective, and the machine accurately predicts features requiring minor post prediction filtering to be accepted as the optimal interpretation.
Industry First Subsea Reentry Multilateral Wells: Case Study
Authors: Ragaglia Simone , Carotenuto Antonio , Napoleone Luca , De Dominicis Guerino , Sakharov Sergey , Latypov Artur , Newman Robert , Guevara Carlos , Rachi Hakim , Revheim Kjell 
Published: December 2021

Abstract
To rapidly increase production from the Goliat Field without adding costly subsea equipment and infrastructure or mobilizing a high-end subsea construction vessel, an operator transformed two single-bore subsea wells into multilateral producers with independently controlled branches.
A multidisciplinary team was assigned to perform a feasibility study for the introduction of multilateral wells. Work started with a reservoir geomechanics/wellbore stability review, based on which well construction/completion basis of design was made. The design and operations sequence were analyzed by a well engineering team. As a result, the main risks, uncertainties, and assumptions were clarified. Two candidate wells were identified, and then a multidisciplinary team was assigned to manage the project, finalize design, initiate procurement, and write procedures. Workshop preparation was closely monitored and reported on a weekly basis. The onshore team closely followed up and supported operational execution.
The new laterals were added to the existing wells, and multilateral junctions were installed and tested. An intelligent completion was installed, and independent branch production started. In addition, the estimated reduction in generation of CO2 is estimated to be between 10 to 20 thousand metric tons per well as compared with drilling two new subsea wells and installing the associated infrastructure.
The technology enables an exploration and production (E&P) company to introduce subsea reentry multilateral technology to increase production while minimizing costs. The process includes well candidate identification, planning, and execution. This practical example can be used for future reference by drilling and production-focused petroleum industry professionals to better understand the benefits and limitations of existing technologies.
Quantitative Evaluation of Well Blowout Risk and Oil Spill Mitigation Measures
Authors: Zausa Fabrizio , Besenzoni Luigi , Caia Alessandro , Mizrak Seda 
Published: December 2021

Abstract
The disaster of Macondo of 2010 changed the rules in reliability and safety standards during drilling operations. New regulations were developed in order to improve the control level on blowout risk, and all upstream operators adopted innovative technologies capable to reduce the potential risk of uncontrolled release, either by decreasing its frequency of occurrence or the expected impacts. The objective of this paper is to present a Quantitative Risk Analysis (QRA) of well blowout and measure the beneficial contribution of intervention technologies in terms of expected reduction of spill volume and associated costs.
The QRA is applied to any kind of well operation (drilling, completion, workover, light intervention) and well type. The methodology relies upon different risk analysis techniques able to quantify the residual blowout risk, as well as the mitigation provided by each technology. Through Fault Tree Analysis (FTA), a value of blowout probability is calculated for each well operation. The initial blowout condition is associated with a blowout flow rate, calculated with fluid dynamic computational models depending on well flow path and release point into the environment. The evolution of each release scenario is then studied with the use of Event Tree Analysis (ETA), where a set of events, able to reduce or stop the flow, are considered with their probability of success and occurrence time (well bridging, water coning, surface intervention through killing/capping techniques, relief well operations). The value of each intervention is estimated through Decision Tree Analysis (DTA), calculating the amount of spill volume reduction and avoided spill costs.
Results of spill volume and cost reduction are calculated for a set of specific wells, considering the application of killing/capping systems as well as Eni innovative technologies. The benefit of these interventions is measured in terms of Expected Monetary Value (EMV) in relation to a potential release extinguished by a relief well, which is the decisive intervention to stop the blowout, considered as the worst case scenario. Surface interventions with killing/capping techniques are the major contributors to the reduction of blowout impacts, and all additional measures which can be adopted should act in the fastest way possible before the arrival of heavy capping stack system.
The main innovative contribution of the proposed QRA methodology is the association of an expected economic value to post-blowout mitigation techniques, which takes into account all possible uncertainties related to their success and intervention time. Moreover, by evaluating an economic impact of the residual spill cost, it is possible to prioritize and increase the overall efficiency of the oil spill response plan for each operational and geographical context, and improve the control on blowout risk mitigation process.
First Permanent Inflow Monitoring Experience in a Smart-Liner, Intelligent-Completion, Multi-Lateral Adnoc Offshore Well
Authors: El Maimouni Fadwa , Mirza Omar , Aissaoui Abdelkader , Almstrong Shawn , Bigno Yann , Keshtta Osama , Almazrouei Gaya , Gharbawi Shihabeldin , Rashed Rasha , Elder Craig , Leung Edmund 
Published: December 2021

Abstract
The scope of this paper is to share a field experience with permanent inflow tracer deployment and monitoring of an intelligent multi-lateral well, completed with Smart-Liner (Limited Entry Liner). It will describe what ADNOC Offshore has learnt through inflow tracing clean up surveillance from several restarts and steady state production through inflow modelling interpretation techniques.
This passive method of permanent monitoring technology utilizes chemistry and materials expertise to design tracers that release signature responses when they come into contact with either in-situ oil or formation water. The chemical tracer technology enables wireless monitoring capabilities for up to five years. Unique chemical tracers are embedded in porous polymer matrix inside tracer carriers along select locations in the lower completion to correlate where the oil and water is flowing in a production well. Interpreting tracer signals can provide zonal rate information by inducing transients to create tracer signals that are transported by flow to surface and captured in sample bottles for analysis. The measured signals are matched with models through history matching to yield zonal rate estimates.
ADNOC Offshore has installed inflow tracers in an intelligent multi-lateral well to monitor laterals’ contributions, to verify new completion technology, and to estimate the flow profile from individual sections of Smart-Liner, run for the first time in the field. The interpretation results have been able to characterize inflow performance without any intervention in the well. Several restart and steady state surveys are planned to understand some key characteristics of the well completion and reveal how the well has changed since it was put on production. This technology will help allocate commingled production to the three laterals. The use of inflow tracers will provide multiple inflow surveys that will reduce operational risk, well site personnel, costs and will improve reservoir management practices. Permanent inflow tracing is expected to change the way production monitoring can be performed, especially in advanced wells where PLTs or Fiber Optic technology cannot access multi-laterals.