bluuebunny/crossref_metadata_2025_split huggingface dataset:
Managing Drilling Risks Associated with Wellbore Departure: Modeling Increases System Reliability while Reducing Operational Costs
Authors: Zhang Zhengxin , Chen Wei , Yun Geng , Liu Xinghan , Dong Yani , Shen Yuelin , Alsup Shelton 
Published: December 2014

Abstract
A typical method to sidetrack from a cased well is to use a milling assembly to traverse an anchored whipstock to create a window, and then continue to drill a rathole deviating from the original well. A sidetrack can also be conducted in an open, uncased wellbore. The operation usually utilizes a directional BHA to traverse anchored or cemented whipstock and drill ahead while steering away from the original wellbore.
To achieve a successful wellbore departure, it is critical to minimize shock/vibration to avoid failure of the milling assembly and drillstring components. The milled window should allow sufficient clearance for the subsequent BHA to pass through without issues. The rathole also needs to deviate away to avoid collision into the original wellbore. Modeling with the capability to evaluate wellbore departure is valuable to plan the operation and avoid unexpected malfunctioning.
The authors describe how a time-based modeling system was used to simulate drillstring dynamics and the cutting action of casing mills. Extensive laboratory tests were done to capture the interaction between the cutting elements/casing, whipstock, cement and formation. The data and the parameters from the specific application were then fed into the model for simulation. The results include milled window profile, rathole wellpath, BHA shock/vibration, and drillstring bending moment/stresses. By studying different scenarios, the milling assembly, BHA and drilling parameters were optimized to reduce the potential for vibration and chance of breakage, and to ensure appropriate window size and rathole length.
Gantry milling tests were conducted in the laboratory. Milling assemblies were used to cut windows in casings cemented in steel containers. Drilling dynamics data including applied weight, RPM and flow rate were collected and analyzed. The geometry of the windows and the profiles of the whipstock were measured after the tests. This information was used to validate the model and good agreement was observed between laboratory tests and modeling results. Validation was also conducted with results from actual field milling runs/operations. The authors will present actual field examples to show the effectiveness of the model to help diagnose and prevent component failure and provide operating parameters recommendations for optimal results.
Field Deployment of an Innovative Acoustic Monitoring System for Remote Real-time Pipeline Asset Integrity
Authors: Schiavon R. , Bernasconi G. , Giunta G. , Borghi G. P. , Okere N. 
Published: December 2014

Abstract
Real-time monitoring of pipeline integrity is a key factor for the environmental sustainability of oil & gas industry.
eni launched in 2009 an R&D project for developing a real-time technology based upon vibroacoustic sensing. In principle any interaction with a pipe filled with gas or liquid generates pressure waves that are guided within the fluid for long distances, carrying information on the source event. Among these events, leaks (due to corrosion, incidents, theft, etc.) are the ones where real-time monitoring has a paramount value.
Starting from 2010, acquisition campaigns in controlled scenarios were carried out and a validation of the mathematical models of pressure wave's propagation in fluid filled pipes was performed. More recently, background noise removal algorithms have been developed to further increase the sensitivity of the system in terms of decreased leak size and false alarm rate. In late 2013 the technology fulfilled the technology innovation qualification system of eni.
Since 2007, NAOC (eni's Nigerian affiliate) has registered a significant increase of oil spill events due to sabotage and oil theft activities. The situation that has arisen posed such risks for the safety of people and for the protection of the environment, that it has been decided to investigate new detection and monitoring systems. In fact, monitoring of the pipelines with other real-time systems which require the presence of sensors all along the pipes (for instance fiber optics technologies) are neither difficult nor economic to implement in the Nigerian existing pipelines. The innovative technology presented here overcomes this weakness, by allowing detecting and locating leaks taking place up to a distance of 35 km from the sensors.
Treatment of Contaminated Synthetic Based Muds (SBM) Drilling Waste in Block 47 Oman
Authors: Nahmad D. , Lepe A. , Rasheed R. , Sajid S. , Al Sabahi J. , Elder R. , Allen M. 
Published: December 2014

Abstract
The development and use of Non Aqueous Fluids (NAF) like Oil Based Muds (OBM) and Synthetic Based Muds (SBM) for drilling operations during exploration and production of Oil & Gas has made the process more efficient and has helped develop new techniques in high depth drilling, offshore drilling and directional and horizontal drilling. The use of OBM's and SBM's carries an additional environmental liability for the operator, as the generated drilling waste ("cuttings") is contaminated with traces of the hydrocarbon base material used to prepare the drilling muds as well as crude oil, that posse an environmental hazard for on-site disposal.
Typically 0.25 bbl of SBM are retained on cuttings per meter of hole drilled, the use of separation equipment and dryers can reduce the final percentage to &lt; 5 % retention on the cuttings. However, this concentration is still high for a safe environmental disposal of the cuttings in most countries thus requiring treatment for further disposal of these solids.
There are 3 main processes currently being used in the industry to deal with these wastes:
The first option is Thermal Desorption (TD) where the cuttings are heated up to 800 C and the cuttings reduced to minerals and ash. The vapors are processed through a condenser and scrubbing system to avoid air emissions. This is an expensive process and requires regular PMS (preventive maintenance)
Second option encapsulation where the cuttings are mixed with lime or silica and cement in varying ratios a concrete block is formed that can be buried in a land fill. Depending on the size of the block and percentage of cement, lime or silica the blocks can end up leaching and releasing the base fluid.
The third and industry accepted application is bioremediation where active enzymes are mixed with water and the oils are digested into cell material, CO2 and H2O, the process is usually applied using land farming techniques.
In this paper, we discuss the use of a technique that uses chemical, physical and biological processes to treat the solids under a land farming protocol that is more effective than straight bio-remediation.
Amine Unit Optimization with High Performance Solvent
Authors: Cadours R. , Turner A. , Suarez Yesika 
Published: December 2014

Abstract
Amine technology is widely used for natural gas sweetening because of its performance and its operability. The main drawback remains the significant energy requirement for the solvent regeneration. To minimize it, amine solvent compositions are today optimized to control the CO2 co-absorption. Mixtures of MethylDiEthanolAmine with proprietary additives are today the state of the art for H2S elimination with controlled CO2 co-absorption. These solvents allow energy saving, and optimized acid gas composition for the downstream processing steps. However, the optimization of the solvent composition may results in less flexibility of the unit. Deep review of the operating conditions may be considered to maintain the benefit of theses formulated solvents.

Results and conclusions
The GASCO industrial complex, one of the biggest in the United Arab Emirates, is composed of four plants: Asab, Bu Hasa, Habshan and Bab and Ruwais, for the extraction of Natural Gas Liquids (NGL) from associated and natural gas. In some units, the optimization of the NGL extraction process has resulted in an optimization of the CO2 co-absorption and GASCO has implemented formulated solvents. The sour gas feed to these units is affected by the upstream operation, including production wells management. The operating conditions of the amine units must be adjusted accordingly, to ensure that the CO2 co-absorption will not result in severe issues in the amine unit or in the downstream processing steps.

Technical contributions
This paper presents GASCO operational feedback with formulated solvents. In particular, it describes how GASCO has reviewed the operation of these units, to deal with the flexibility of the sour feed gas (composition or flowrate), with the constraint of a formulated solvent. Impact on the amine unit equipment's and on the downstream process steps is also commented upon.
Water Saturation in Transition Zone in Carbonate Reservoirs: Reconciling Open Hole Log and Capillary Pressure
Authors: Zahaf Kamel , Bourdarot Gilles , Low Steven 
Published: December 2014

Abstract
Modeling initial water saturation in transition zones in Carbonate has been a long lasting challenge particularly in heterogeneous reservoirs. The variation of water saturation has a considerable impact on initial volumes estimation, oil recovery prediction as well as the design of field development plans.
Log-derived saturation can suffer from interpretation uncertainties particularly in the transition zone associated with the lack of knowledge of Archie exponents and especially n variability related to wettability. Moreover in the transition zone True Formation Resistivity ("Rt") evaluation presents a wide range of uncertainties as Laterolog and Induction Log domains overlap. Therefore there is a strong need for an independent source of water saturation profile.
Mercury Injection Capillary Pressure (MICP), Porous Plate and Oil-Displacing-Brine Capillary Pressure measurements on core samples, at reservoir conditions, are used for building a reliable saturation profile for different rock types. In this paper the reconciliation process of water saturation from revised log analysis, laboratory measurements and Water Oil Contact takes into account the uncertainties on each source of data acquisition.
The proposed methodology has been applied to a giant carbonate reservoir in Abu Dhabi and has improved the robustness of the water saturation evaluation in the transition zone. Production data are in a good agreement which supports the consistency of the methodology.
Wastage Profile Study in Giant Offshore Oilfield, a Well Integrity approach to Optimize ICD Well Completion Design and Improve Corrosion Management for MRC wells.
Authors: Alvarez Adriana , Samad S. , Jackson A. , Bachar S. , Kofoed C. W. , Edmonstone G. , Abdouche G. , Shuchart C. , Troshko A. , Mayer C. 
Published: December 2014

Abstract
For the last 30 years, wells in the field have been suffering from medium to high corrosion rates in both near surface and downhole components. Remedial measures had been implemented in order to restore Well Integrity with different techniques. Corrective actions aside, a strong preventive approach is needed to better understand the root causes of such corrosion rates and scenarios where the integrity of specific wells has been seriously compromised due to corrosion problems.
Taking a step further and considering the big implications of new projects such as Artificial Islands project, where the company will be drilling & completing over 300 Extended Reach Drilling (ERD) wells, Well Integrity input as a discipline becomes critical in order to ensure previous problems will not be repeated and all lessons learned throughout the years will be wisely taken into consideration when designing a new well to remain integral during its whole expected life.
Understanding of the current corrosion mechanisms in the field was the key to find not only solutions, but also, to create an approach aimed to improve the future completion for Island wells in terms of design, materials and many other factors.
An extensive multidisciplinary approach was carried out in order to successfully complete a full study in one of the pilot wells completed with Inflow Control Devices (ICDs), which will be analyzed in detail in this paper, covering the following areas: Well design and configurationWell monitoring and performance reviewWell diagnosis and failure investigationPost-Failure modelling and well predictionPreventive/Corrective actions for future wells.
Corrosion management and prevention of scale deposits were the two main challenges encountered during this project, which was launched and completed with the main objective of evaluate and optimize the ICD completion design in one Maximum Reservoir Contact (MRC) pilot well in the field, the findings and lessons learnt were used to upgrade the current well design and improve the development plan for the field.
First Installation of Efficient and Accurate Multilaterals Stimulation Technology in Carbonate Reservoir
Authors: Rice Kevin , Jorgensen Thomas , Waters Jeremy 
Published: December 2014

Abstract
In many cases, carbonate oil wells are stimulated with open hole acid flush or acid fracturing treatments to increase productivity. Some of the challenges with fracturing stimulation are reservoir related, such as consistently stimulating all targeted intervals and intersecting the natural fracture network. The growth of hydraulic fractures in the vertical direction is difficult to predict, leading to the risk for entering unsought gas or water-bearing formation. Operations can be complex, costly and pose environmental challenges. A multilaterals stimulation technology (MST) has been developed and field tested to be a simple, efficient and more controllable method of stimulation with less environmental impact. The method uses less fluid, reduces the risk of groundwater contamination and eliminates stimulation fluid flowback disposal. This paper discusses the evolution of the technology, leading to the first pilot installation in a horizontal well in the Austin Chalk carbonate reservoir in Texas, during April of 2014. The pilot installation proved the stimulation technology's efficiency by creating 60 laterals, each 40 feet long, in a few hours pumping time. This installation is believed to be a world record for creating 60 laterals in less than 5 hours. The well's production response was significant, and productivity index was increased by 30 times compared to before the stimulation.
Microbial Corrosion. New Investigation Techniques
Authors: Hoxha G , Di Iorio C. , De Ferra F. 
Published: December 2014

Abstract
Microbiological corrosion (MIC) is a form of localized corrosion due to microorganisms activity. By-products of specific metabolic reaction modify locally the ambient in contact with metallic surface, thus triggering and accelerating corrosion attack.
Oil and gas plants, in particular those of mature fields, can be affected by this corrosion form. Despite that the influence of microbiological activity on corrosion phenomena has been for years overlooked. One of the reasons of this approach could be that traditional investigation techniques were unable to correctly evidence and estimate the entity and complexity of microbiological contamination. The application of methods of molecular biology has opened new possibilities for identification and evaluation of effect of microorganisms on corrosion phenomena.
The aim of this paper is to describe the approach of eni e&p for the monitoring and investigation of MIC.
Outstanding Production Performance Through the Extreme-Lean Profile Well Design: an Example of Drilling Operational Excellence that Allowed Reaching the Reservoir Target with a Bigger Hole Size in a Mature Field
Authors: Puliti Alessandro , Molaschi Claudio , Maliardi Alberto , De Grandis Giuseppe 
Published: December 2014

Abstract
This paper highlights how the implementation of an extreme lean casing profile for the well construction, can really make the difference to achieve operational excellence.
This is the case of the successful application in a mature field, where, for the first time, the reservoir target has been reached with a horizontal 8½″ hole section within naturally fractured carbonate formations.
In such occasion, the extreme lean profile has made it possible to reach the reservoir with a bigger production hole diameter, compared to the previous wells drilled in the same area; this has allowed the accomplishment of an outstanding production performance, also thanks to the lower pressure losses inside the 8 ½″ open hole section.
The reduced clearance between casing and borehole represents a distinctive characteristic of the extreme lean profile; this enables using two additional casing strings, as a contingency for well construction or as extra casings to reach deeper targets with the same production hole diameter or, as in this case, start with a smaller surface hole while simultaneously reaching the reservoir with a production hole diameter larger than those of conventional wells.
Furthermore, the specific well design has allowed to reduce the drilling time, improve borehole stability thanks to the smaller hole sections, and decrease the environmental impact as a result of the reduced volume of cuttings produced.
This paper provides a comprehensive description of the well requirements, the associated operational issues, the chosen solutions and the actual challenges encountered during drilling operations. The achieved results are also described.
Production Performance in Marcellus Shale: Multidisciplinary Study of Hydraulic Fracturing
Authors: Izadi Ghazal , Junca Jean-Philippe , Cade Randall , Rowan Tom 
Published: December 2014

Abstract
The Marcellus Shale is one of the main U.S. shale plays with more than 140 trillion cubic feet (Tcf) of recoverable gas/condensate (E.I.A) in Pennsylvania and West Virginia. Using the appropriate completion and stimulation designs for reservoirs in a given location is crucial to increase the productivity of the play. Understanding rock properties and reservoir characteristics in gas condensate area and their behaviors during the well stimulation is necessary in order to optimize treatment design. This case study aims at optimizing well and completion design parameters such as well spacing, lateral length, azimuth or hydraulic fracturing properties and improving well productivity. An integrated reservoir study involving geomechanics, fracture design and production analysis was carried out, coupled to a multivariable statistical analysis. The purpose of this paper is to apply multivariable statistical analysis in conjunction with production analysis to understand the relationships between rock properties and hydraulic fracturing efficiency within the reservoir. Fifty percent of the Marcellus Shale is composed of clay in the area of interest and typically, clay shales are anisotropic in strength and deformability. The brittle failure characteristics vary from east to west of the play which can affect the proppant transport and ultimately the well productivity. The investigation is based on both proprietary and public information data for the Marcellus formation (around the area of interest in Marshal County, West Virginia). Production proxies, such as maximum gas and condensate rate in the first 12 producing months were selected and merged with well completion and stimulation data. Final data sets were then subjected to a multivariable statistical analysis and a commercial Geographic Information Systems (GIS) application was used to understand geographical performance variation within the play. Fracture modeling and Rate Transient Analysis (RTA) were applied to this study to identify flow regimes and obtain determine some hydraulic fracture and reservoir properties. At last, the relationships between well performances, completion design and reservoir behavior were better understood.
Case History - The First S4 Survey in Abu Dhabi
Authors: Marmash Samer , Al Jenaibi Mahfoud Salah , Al Jeelani Omar Sultan , Haggag Ismail B. , Morrison David , Glushchenko Anna 
Published: December 2014

Abstract
Abu Dhabi Company for Onshore Oil Operations (ADCO) had a need for an exploration survey to delineate a low relief structure in onshore Abu Dhabi. The terrain is characterized by sand dunes of variable heights with some oilfield infrastructure, farms and conservation areas. ADCO tendered for a conventional survey but the successful bidder offered an economically attractive Single Sensor / Single Source (S4) option with the MD low frequency enhanced sweep. ADCO has tested some of the processing technology associated with S4 recording on vintage datasets and were keen to try them on a true S4 dataset.
In particular it was very important that a good near surface model was obtained because of the low relief target. The use of the low frequency MD sweep, Shear Wave Inversion (SWI) and Simultaneous Joint Inversion (SJI) was an ideal approach to resolving the near surface model. There was an uphole program planned to calibrate the derived near surface model. The SWI volume was generated before the upholes were drilled so that any anomalies could be investigated.
The crew with 50,000 channels mobilized and commenced operations on October 26th 2013 and completed the 604 Sq.km survey by December 25th. The survey consisted of 241,860 VP's and generated 3.5 billion traces. Despite this volume of data a field QC volume was generated on the crew utilizing a pre-defined velocity field developed in collaboration with ADCO and was delivered two days after the last shot. This volume was interpretable to guide the main processing team.
Whilst the full processing and evaluation of the data is still ongoing, the early results have clearly shown that the S4 technique is ideally suited to acquisition in sand dune areas with infrastructure. This presentation outlines the details of this survey and the lessons learned.