bluuebunny/crossref_metadata_2025_split huggingface dataset:
Overcoming Challenges in Managing Wellbore Stability Issues in Deviated 12-1/4" Hole Section while Drilling an Appraisal Well in a Sour Gas-Condensate Field: A Case Study
Authors: Richardson D. , Rosener A. , Louison W. , Al Ameri F. 
Published: November 2015

Abstract
In attempting to drill a deviated 12-1/4″ 37° tanget section with WBM through the Laffan and Nahr Umr shale intervals, very little margin for error was faced in a well where failure was not an option. While problems in the Nahr Umr were to be expected, the instability of the Fiqa and Laffan shale layers became the catalyst for excessive non-productive time. Two lost holes preceded the successful completion of the section after taking the last resort step of a re-drill with Synthetic Oil Based Mud (SOBM).
Various literature is available on wellbore stability problems in the Nahr Umr Formation on a regional and field specific scale. Behaviour of the shale and how best to control it is also known to vary on a field by field basis. Failure mechanisms are largely related to the mineralogical composition of the shale itself in combination with the localized geomechanical forces exerted on the specific wellbore. This paper captures the specific experience encountered in the operator's first well in the country and provides insight into the severity of the risk of wellbore instability.
Numerous operational issues were encountered due to shale instability induced through drilling and tripping related mechanical forces. Before committing to the changeover to SOBM, exhaustive attempts were made to find an acceptable and workable compromise to the challenges faced while drilling the section with WBM. This included implementation of alternative methods of well construction including the use of innovative tools and hole enlargement to increase annular clearances with the BHA. Often it was observed that mitigation of one problem led to the onset of another problem.
The experience is used to present an overview of the limitations of the contingency options available and the impact of unplanned changes implemented during the well construction phase.
In addition to the engineering conclusions presented, the case study provides insight into the complexities of a start-up drilling operation. Where an entire field appraisal campaign depends on the successful accomplishment of primary objectives, the necessity to perservere through adversity becomes of yet higher importance.
Investigation of Methods of Enhancing the Performance of Propane Pre-Cooling Refrigeration Cycles in Natural Gas Liquefaction Processes
Authors: Mazyan W. I. , Ahmadi A. , Ahmed H. , Hoorfar M. 
Published: November 2015

Abstract
This paper examines the viability of using low cost techniques to increase the performance (COP) of the overall natural gas liquefaction processes. Mixing propane with ammonia, sulfur dioxide or carbon dioxide and their effect on the compressor's required work is studied. The simulation results show that propane-ammonia and propane-sulfur dioxide mixtures enhance the COP by a maximum value of 7% and 9%, respectively. The COP enhancement in these blends is due to the closeness of their boiling temperatures with the operating temperature. However, the addition of carbon dioxide to the propane refrigerant reduces the COPof the cycle. This reduction is due to the poor energy absorption capabilities of carbon dioxide at the cycle operating temperature. The goal of this study is to investigate the feasibility of enhancing the COP using mixed refrigerants consisting of a hydrocarbon (propane) and natural fluids (ammonia, sulfur dioxide and carbon dioxide).
Using KCl to Mitigate Chemical Instability and Advanced Logging to Measure the Results in Well Top Hole Sections
Authors: Shaver Michael Alexander , Al Katheeri Yousif , Kvalvaag Edvin , Kustanto Sigit , Edwards Henry Ewart , Boyd Douglas Alexander , Shabaan Mohamed , Dasgupta Suvodip , Girinathan Sajith , Raina Ishan , Aziz Faiza 
Published: November 2015

Abstract
ZADCO's new field development program calls for drilling extended reach wells from artificial islands with the borehole kicking off at shallow depths and holding high inclination angles through the overburden. Previously, the development plan relied entirely on short reach, horizontal development wells drilled from jackup rigs with shallow overburden borehole sail angles rarely exceeding 30°. For both types of wells, bentonite weighted sea water is the preferred drilling fluid for the 16″ or 17.5″ diameter holes. Drilling problems that were managed in low-inclination wells became exacerbated at higher angles causing significant rig non-productive time (NPT). To improve our understanding of the shallow overburden formations, a comprehensive logging program was conducted in a key well drilled with a potassium chloride (KCl) mud system. Wireline borehole image, dipole shear sonic, spectroscopy and neutron-density-resistivity triple-combo logs were used to characterize the formations.
A successful logging program relies on maintaining the borehole in good condition. In this case, the KCl mud in conjunction with good drilling practices kept the hole near the 16″ bit gauge for 90% of the interval. Drilling mud losses were also minimized. The logging tools were successfully run to T.D. and the data acquired. The mineralogy of the penetrated formations was accurately quantified using spectroscopy tools. A high-resolution resistivity image log revealed that the entire interval was weakly fractured with a few zones of high secondary porosity and conductivity. These zones correlated well with zones of similar characteristics in offset wells. The key to drilling a high angle well lies is the geomechanical / geochemical characterization of the overburden formations to determine the wellbore failure mechanism(s).
This paper highlights the benefits of a KCl mud in the top hole and the results of advanced logging covering the predominately shallow carbonate formations that exist above a large carbonate reservoir. It emphasizes the need for characterizing not only the reservoir but the overburden formations. This advances drilling engineers’ understanding of formation characteristics so that increased drilling sail angles could be achieved through the shallow overburden and thus successfully reach the reservoir targets.
Internal Inspection - Can this be Achieved "Externally" for Pressure Equipment!
Authors: Shams Ahmed , Al Abri Ahmed , Coelho Jose' , Giridhar Y. V. 
Published: November 2015

Abstract
Legal Internal inspection requires pressure equipment shutdown, HSE clearance for safe man entry. These costs can be much higher than the cost of inspection itself. Furthermore, also mechanical damages can be caused during preparation for inspection and more importantly man entry in the equipment for examination is a health hazard.
Non-intrusive Inspection (NII) is an examination of a pressure vessel without any personnel entry, which can be applied whilst the equipment is in service. NII is a stringent engineering process in which inspection tasks are designed with the aim of replacement or deferment of a conventional internal visual inspection (IVI), where comprehensive planning and evaluation are carried out to ensure the inspection meets a specified criteria under an equivalent or higher level of confidence than IVI. NII technology has an extensive advantage if inspection is performed from the outside of the vessel without opening i.e. non-intrusively.
Advancements of Shell Cansolv in Post-Combustion CO2 Capture Technology
Authors: Abdollahi Farhang , Shaw Devin 
Published: November 2015

Abstract
An affordable and reliable Carbon Capture&Storage (CCS) technology is the key step to reduce CO2 emission from new and existing coal-fired and Gas power plant, as well as large industrial sources. With the milestone start-up of the Boundary Dam Carbon Capture and EOR project (Saskatchewan Canada, 2014), Shell Cansolv's technology became the world's first technology deployed in post-combustion carbon capture at commercial scale in the coal-fired power industry. This coupled with on-going operations in post-combustion CO2 capture for utilization in the industrial and chemical market, as well as an on-going front end engineering design (FEED) for CO2 capture from a combined cycle gas turbine (CCGT) power station. The Shell Cansolv CO2 capture technology has accumulated a spectrum of experience and learnings covering Enhanced Oil Recovery (EOR), CCU and CCS.
To open, this presentation will provide a project summary of Shell Cansolv in an on-going EOR, CCU and CCS application. Moreover, it will focus on the Shell Cansolv CO2 capture technology, providing a detailed technical description of how the line-up is adapted per application and provide rationale and relative performance indicators in each. A summary of the balance required to deliver the best Net Present Value (NPV) solution will be provided, such as the important considerations of optimization trade-offs on a per project basis, including: Increasing NPVOperations simplicityAcceptable Scale-up instead of multiple trainsEvolution in CANSOLV new solvents, their specifications and applicationsIntegration complexity vs. stand-alone robustnessA design for maximized availability, flexibility and cost-effective
In conclusion, a description of some of the key learnings accumulated in each application will be discussed, as well as an indication of where we think the next breakthrough changes can and will be made.
Well Performance Improvement Using Complex Nano Fluids
Authors: Kutty Shanof Mohamed , Kuliyev Myrat , Hussein Mohamed Abdelsalam , Chitre Sunil , Mustafa Hammad , Penny Glenn , Wehbeh Jamal , Germack David , Shedd Daniel , Lelenwa Chilezie 
Published: November 2015

Abstract
ADMA OPCO has started operations for a full field development plan in a green field located in offshore Abu Dhabi. All reservoirs are carbonates (dolomites and limestones) and thus acid stimulation is required post well completion in order to increase the well production/injection rate. During the planning stage, an extensive acid recipe study was carried out to formulate stimulation treatments to meet the challenging complexities of the reservoirs, high downhole temperatures and long corrosion protection time. Several lab tests were carried out to formulate all the acid recipes.
While in quest of new technology, an additive called ‘Complex Nano Fluid’ was introduced in the acid recipes based on proven case histories from around the world. This was also confirmed with the lab tests using ADMA reservoir crude and core samples. It is expected that by including nano fluids in matrix stimulation fluids, the overall productivity enhancement will be approximately 40% greater than conventional treatment approches. Most of the tests were performed in Abu Dhabi, however special wormholing tests with CT scan were done in a lab in Houston to evaluate the effectiveness of nano fluids on core samples.
This paper details the acid recipe work flow process, the different lab tests that were carried out to formulate the acid recipes, mechanism of complex nano fluid and its advantages.
SmartSulf™ Process in Direct Oxydation Mode for Very Lean Acid Gas Application
Authors: Heim Thibaut , Mares Benoit , Simonneau Vincent 
Published: November 2015

Abstract
Due to higher demand in desulfurization and new environmental regulations, Companies need to find robust and efficient technologies while considering the best approach to minimize CAPEX and OPEX. With more stringent regulations in terms of sulfur emissions to the atmosphere, some Companies have no choice but investing in new sulfur removal units. Some industries need to treat diluted acid gas with H2S concentrations below 15% vol. containing various impurities with, in some instances, huge hydraulic capacities. Some technologies can offer suitable solutions in terms of performance but investment and operating costs can be very high.
The SmartSulf™ technology used in a Direct Oxidation scheme can offer a proven solution for industries dealing with low H2S concentration (gasification, biogas, carbon black, natural gas…). The technology can be used in new facilities or, thanks to its low footprint, used in existing facilities for retrofitting. The core of the process is the implementation of a cooling system inside the catalytic reactor. Details and principle of operation of such cooling system are presented. The process configuration can also propose a sulfur subdewpoint mode where sulfur is directly adsorbed on the catalyst leading to higher recoveries. Based on a smart switching system, the process offers a simple and fully automatic operation allowing continuous adsorption and regeneration cycles.
Several configurations are available for the SmartSulf™ in direct oxidation mode based mainly on the acid gas H2S concentration and on the required performance.
This paper focus on the SmartSulf™ process used in direct oxidation mode and gives feedbacks from the existing facilities where the technology is already in operation for many years.
Corrosion Management Challenges of Non-Piggable Pipelines, Sections & Dead Legs
Authors: Dutta Rajdeep , Al Suwaidi Ibrahim Mohamed 
Published: November 2015

Abstract
Most operating oil and gas companies possess pipeline assets and In-line Inspections (ILI) are the most effective ways to assess the integrity of a pipeline. However to carry out ILI the pipeline should be piggable. Asset integrity audits have identified that while main pipelines are piggable most inter connectors, branches and by-passes are not in the pig’s path. Some sections while no longer in use, are still connected with the live system. These sections may be used rarely and therefore not an operational priority. However these ‘weak links’ pose a major threat to overall system integrity.
Many of these non-piggable pipelines do not have a corrosion control strategy and the technical integrity of most is unknown. This has been identified as a high integrity risk to operating companies with respect to loss of production, high cost of failure/degradation and high failure safety risk. As part of the technical integrity drive and risk management strategy, a need was identified to develop the strategy to assure the integrity of non-piggable pipelines / sections.
A thorough technical analysis made with advantages and limitations of available integrity assessment methods for non-piggable pipelines, such as: Hydrostatic Pressure Testing, External MFL Survey, Long Range Ultrasonic Thickness (LRUT) and Corrosion Direct Assessment (CDA). Based on the analysis, the most effective and techno-economic solutions were recommended and adopted by Dolphin Energy for its on-shore pipeline network in the UAE namely LRUT.
Dolphin Energy operates approximately 750 Km of gas transmission and successfully completed an LRUT inspection project - Phase-1 in 2012 comprising 9 locations and Phase-2 in 2014 - comprising 52 locations throughout the UAE. Post project assessment was made where LRUT inspection and corrosion direct assessment results were analyzed together. Post assessment specifically addressed the effectiveness of methods used, corrosion root cause analysis, a corrective action plan, remaining life calculations and determination of re-assessment interval of each non-piggable pipeline.
This paper addresses the new strategy developed and successfully implemented by Dolphin Energy to address the challenges associated with these non-piggable pipelines, sections and dead legs. Through this paper other operating companies who face similar challenges will benefit from the experiences of Dolphin Energy.
Design Approach to Overcome Brownfield and Shutdown Constraints
Authors: Subramanian T S , Adel Khalid , Al Awadhi Ibrahim 
Published: November 2015

Abstract
Performing major refurbishment works in brownfield, within limited shutdown window, pose challenges to the methodology adopted for the design and execution, especially if the structure involved is critical to Plant operations and requires significant modifications to ensure integrity / durability and minimise plant disruptions. This paper presents some such challenges and the methods deployed to overcome the same in one of the projects executed by GASCO.
Abu Dhabi Gas Industries Limited (GASCO) operates gas processing plants in the emirate of Abu Dhabi. At one of the plants, a burn pit is provided for emergency relief. The Burn pit was constructed in 1999-2000 and experienced frequent damages to refractory lining, leading to Plant outages for repair, thereby resulting in production losses. A technical study was carried out to evaluate different options for refurbishment and recommend a robust solution, considering the existing physical constraints and the challenging shutdown window requirements. The design phase involved exploring different configurations for the arrangements, discussions with refractory vendors to select the appropriate materials, and consultations with recognized contractors for the execution methodology and the duration.
The selected option involved complete demolition of the existing refractory and concrete structure, and replacement with a new concrete structure, covered with refractory lining. The concrete structure was designed and executed in pre-cast modules. The burner block, comprising of sleeve and castable refractory (for housing the burner tip) was also precast at contractor’s yard and dry-out during pre-shutdown phase was carried out. The pre-casting of modules allowed for pre-installation of anchors required to hold the refractory lining in position.
This option facilitated significant pre-shutdown works and ensured execution readiness during shutdown. As a result, all works involving demolition of existing structure, clearing the area of debris, construction of new structure using precast modules, application of refractory, etc. were completed and the burn pit was handed over to Plant operations three days ahead of schedule. This also contributed to cost savings, by maintaining long term integrity of the structure and reducing plant outages for maintenance.
A Novel Holistic Approach to Make Informed Business Decisions - Utilizing Formation Pressure Data from a Complex Giant Carbonate Field in Abu Dhabi
Authors: Ahmad Fazeel , Khan Muhammad Navaid , Sarsekov Arlen , Saif Omar Yousef , Al-Neaimi Ahmed Khalifa , Al-Alyak Abbas 
Published: November 2015

Abstract
The formation pressure testing data is widely used in the oil & gas industry to understand the reservoir vertical heterogeneity and the fluid movement within the reservoir. With the recent advances in formation testing technology, now the subsurface engineers are able to visualize the rock and fluid characteristics beyond the conventional few centimeters into the formation without putting the well on production.
A study for integrating all available formation pressure data was carried out in a field scale level. The holistic analysis of the data enabled the reservoir engineers to deduce critical information, such as, reservoir compartmentalization, reservoir depletion trend and the injectors’ efficiency.
The aim of this paper is to demonstrate a novel approach of analyzing formation testing data on a field scale from a complex reservoir that enabled ADMA-OPCO subsurface team to make informed decisions for better reservoir management. Certainly, the replication of this analysis approach could benefit the petroleum community in the similar field development scenarios.
Geological Mapping of Early Diagenetic Bodies as a Tool to Distribute Permeability in a Mature Giant Carbonate Field
Authors: Koppen J. van , Al-Menhali H. , Alblooshi A. , Caline B. , Guy L. , Kheidri H. , Hu T. , Kwasniewski A. , Dubois L. , San Miguel G. , Duval C. , Deviese E. , Thomas E. , Vanhalst M. , Dreno C. , Mel R. , Elhami M. 
Published: November 2015

Abstract
Revealing the coherency between geology and petrophysics in a mature carbonate field in order to provide 3D distribution of permeability is challenging.
This paper shows how integration of early diagenetic processes is a prerequisite in understanding the behaviour of a heterogeneous carbonate field. However, mapping of early diagenetic overprint requires the preliminary mapping of the main depositional belts per stratigraphic sequence as the relevant diagenetic processes occurred during or shortly after deposition. For instance, diagenetic processes associated with vadose dissolution or reflux dolomitisation significantly enhance matrix permeability of the reservoir. Mapping of diagenesis has therefore been used as a tool to constrain permeability distribution within depositional sequences in combination with the interpretation of available dynamic reservoir data. The resulting geomodel better honours the heterogeneities and the dynamic behaviour of the field.
Mud Weight Optimization to Reduce Non-Productive-Time While Drilling Through Shale/Carbonate Sequence of UAE: A Case Study
Authors: Xi GuiFen , labbassen Nabila , Al Badi Bader Saif , Lecoq Thierry Francis , Afifi Hassan Al-Husseiny , Al-Marzooqi Abdul Mohsen , Mais Nassim El , Mavromatidis Angelos , Ofield William , Rodriguez Jose 
Published: November 2015

Abstract
Maintaining wellbore stable is one of the key tasks in the oil and gas industry, in order to reduce nonproductive time during drilling, because wellbore instability problems would lead to higher than necessary drilling costs and have a severe impact on drilling schedule. Wellbore stability is controlled by two type of factors, one type is the factors which are completely out of our control, such as in-situ stresses, pore pressure, and rock strength, the other type is the factors which we can optimize and design to minimize geomechanical related stability problems, such as well trajectory, casing seats, mud system, mud weight, and proper drilling practice including minimizing swab and surge while running pipe and reducing the stationary time during connection.
In this paper, only the mud weight optimization and casing seats design will be focused on, in order to avoid geomechanical related instability issues for drilling a recently planned appraisal well in an offshore field.
Mechanical properties including Young's modulus, Poisson's ratio, USC, friction angle, tensile strength, bulk density and pore pressure gradient obtained from two offset wells A1 and A2 were projected to the planned appraisal well A3 with tops were used as guidance. The same parameters optimized from those two offset wells were used to estimate horizontal stresses for the planned well, and the same failure criterion was used to carry out wellbore stability for the planned well. Meanwhile the mud weight corresponding to kick, breakout, loses and breakdown were obtained. Based on those results, the safe mud weight window was established and the casing seats were placed to prevent and reduce the geomechanics related instability problems.
This methodology allows us to predict and prevent the geomechanics related instability issues in advance before drilling starts, thereby to reduce the non-productive time and drilling costs. Continuous updating of the geomechanical model is necessary during drilling if the geological environment is complicated.