bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Value of Reservoir Surveillance - Applications to Fractured Carbonates Under Waterflooding
Authors: Shbair Alaa F. , Al Hammadi Hamdan , Martinez John , Adeoye Olanike , Abdou Medhat , Saputelli Luigi , Bahrini Fahmi 
Published: November 2017

Abstract
As reservoirs mature, subsurface flow complexity and surface production operation challenges increase. This brings the necessity of making capital-intensive decisions to sustain or increase reservoir potential in an optimum way. However, subsurface uncertainties affect decision success. Reservoir surveillance, a process that involves data acquisition, validation, analysis, integration opportunity generation and execution, can mitigate the outcome of such decisions in the presence of uncertainties.
Although Value of Information (VOI) is a well-known process for justifying data acquisition, engineers struggle to extract the relevant information from historical data to apply Bayesian approach.
The objective of this paper is to illustrate a methodology for identifying the value of information in reservoir management, in particular for deriving the conditional probabilities of success when new and imperfect data are acquired. A methodology to assess the value of reservoir surveillance is supported by two cases.
In the first case, the incremental value of Real-Time Reservoir Characterization (RTRC) in underbalanced drilling (UBD) was nearly 100 times the cost of the services; in the second case, the incremental value of permananet downhole gauges (PDHG) was near 230 times the cost of installation and services. Reliability of facquired data, among other uncertainties, resulted to be a key success factor for both cases; however, in worst-case conditions, the incremental value was always positive.
NGL Recovery - A New Concept for an Old Scrubber
Authors: Jariwala Ankur , Sanghani Pinkesh , Kvamsdal Dag 
Published: November 2017

Abstract
Gas scrubbers are designed to protect process equipment, such as compressors, dehydration towers, pipelines and molecular sieves from liquids. The efficiency of gas scrubbers for separating natural gas liquids (NGLs) is critical to the recovery of most of the entrained NGL before the gas is routed downstream to pipelines.
We present a specific case study in Southeast Asia where offshore production was delivering 300 MMscf/d of gas to an onshore gas processing facility. The gas was chilled in a mechanical refrigeration unit, and liquids were separated in a vertical scrubber equipped with a simple inlet device and mesh pad assembly. The scrubber was designed to handle 450 MMSCFD. Due to an inefficient scrubber design, the facility was experiencing NGL liquid carryover from the scrubber into the pipelines with the original design basis. The scrubber thereby showed significant amount of liquid carryover of 1,550 BPD of natural gas liquids into the gas pipelines.
Computational fluid dynamics modeling of the scenario clearly showed loss in separation efficiency and NGL carryover from the scrubber to the downstream pipeline, documenting that the existing scrubber was not suitable for such high gas loading and increased gas volume.
Customer approached Schlumberger to retrofit scrubber with a new design and resolve the existing liquid carryover issues which led to revenue loss. We have experience in desiging novel internals such as axial cyclonic inlet (ACI) in these kind of scrubber vessels. These have been tested and optimized in the laboratory using model fluids and further tested in a high-pressure real fluid testing loop. Test results show that ACI provides the required gas/liquid separation efficiency under the higher gas loading and thereby increases the overall separation efficiency to 99.9+%.
The retrofit scrubber was designed to process 450 -500 Mmscfd of gas and increase the NGL production by 8540 BPD showing high ROI for the customer. The scrubber with the ACI shows consistently higher separation efficiency even under turndown or lower inlet gas flow conditions.
We present details of the retrofit scrubber design, importance of using high efficiency separation internals, CFD anlaysis and present test results verifying the liquid carryover before and after implementation of the new inlet section.
Use of Surface Waves for Near-Surface Characterization and Drilling Hazard Reduction
Authors: Al Mesaabi S. , Mohammed M. , Tertrais B. , Bardainne T. , Garceran K. 
Published: November 2017

Abstract
To overcome the lack of information on the most superficial part of the near surface obtained by the use of the First Arrivals (refracted waves), we have implemented an innovative combined workflow that use the information from the Surface Waves (Rayleigh waves) to complement the first-break measurements. As the Rayleigh waves propagates along the free surface interface, they carry significantly more detailed information of the near-surface characteristics which can be used to better constrain the first-break inversion.
The first step of the workflow starts with the surface wave dispersion curve picking. As reliability of the results directly depends on the quality of that picking, data regularization are used to improve picks accuracy on both low and high frequency of the phase velocity/frequency spectra. A surface wave tomography process is then applied to convert the spatially irregular frequency-dependent picks into a regularized (x, y, frequency) Rayleigh wave’s velocity volume. Lastly a laterally constrained depth inversion is performed, delivering a 3D shear wave’s near-surface depth velocity model.
The second step of this workflow uses this S-wave velocity model, which contains the near-surface details captured by the Surface-Waves, to constrain the refracted P-wave first-break tomography. A regional scaling, here a 1D VP/VS ratio estimated from knowledge over the area or from fast-track refraction first-break analysis, is required to convert the S-wave velocity into a P-wave model. The constrained tomography aims to scale the trend from the high-resolution S-waves velocity model by fitting it with the trend of the P-wave field derived from the first arrivals. This corresponds in a sense in inverting the VP/VS ratio in such a way to preserve the high-resolution feature scaptured by the surface waves while remaining consistent with P-wave information. The resulting near-surface velocity model looks more geologic, better respects P-wave travel times and can be used with more confidence to compute the primary statics solution than the conventional P-wave field only obtained from the first-arrivals tomography…
Furthermore, this accurate update of VP/VS ratio can be used to estimate the Poison’s ratio. It can be used to better plan geotechnical survey in order to reduce shallow drilling hazards.
An Innovative Approach of Nuclear Magnetic Resonance 2D-T1T2 to Identify Complex Reservoir Fluid Regime of Gas-Condensate in Newly Discovered & Fast Appraisal Carbonate Reservoir Field of Abu Dhabi, UAE.
Authors: Singh Maniesh , Bankole Ibukun , Aldahmani Asma , Alzeyoudi Mona , Hajri Zaher Al , Bahri Sami El , Ahmad Mula Nur , Balliet Ron , Vican Kresimir , Jambunathan Venkat 
Published: November 2017

Abstract
This paper covers a case study of successfully applying innovative NMR logging technology for fluid typing using continuous measurement from longitudinal and transverse relaxation two dimensional (2D) maps (2D T1T2app), helped in reducing fluid typing uncertainty in different clusters of one of the recent discovered gas-condensate Cretaceous stacked carbonate reservoirs of Abu Dhabi field.
Generally, the reservoir fluid type in gas-condensate reservoir is confirmed by observing a representative fluid sample in laboratory, but at times collecting representative sample becomes challenging especially in tighter formations or unstable wells or rugose holes.
The advanced logging techniques, such as Nuclear Magnetic Resonance (NMR) and Downhole Wireline Formation Testers (FT) with pump-out fluid sensors, can be extremely beneficial in resolving fluid types in downhole reservoir condition for such complex fluid regimes and is also applied in this recently discovered carbonate field. NMR continuous T1T2 (simultaneous longitudinal relaxation-T1 & transverse relaxation-T2) logging & 2D fluid characterization methods at closer interval have been very important and useful data to assist in differentiating condensate, gas, and water in each of the reservoir in the static condition. Free gas (methane) occupies a unique location in a 2D T1T2app map with a relatively long T1 and short T2 signature. Dead oils or low GOR oils typically have a low T1T2 ratio and condensates are identified by their fairly large T1T2 ratio. The fluid signatures from the 2D maps are then quantified to compute individual fluid volume for hydrocarbons and water. Reservoir fluid typing from NMR 2D T1T2app not only helped in optimizing formation tester PVT sample points, but was also found in agreement with fluid analysis results from formation tester sensors where reservoir fluids were sampled from a greater distance from wellbore after longer duration of pump-out period.
The NMR Fluid typing using 2D-T1T2 app has helped identifying gas-condensate-water fluid types in static condition before sampling or testing. This has helped to understand regional fluid distribution in tighter reservoirs especially where fluid gradient has not helped due to unreliable formation pressure data.
By applying NMR fluid typing in difficult gas-condensate fluid regime validated further by fluid sampling and testing, has provided confidence in placing perforation at correct depth for testing, improving regional fluid distribution and bringing timely value to optimize engineering techniques for fast track appraisal & development program.
Environmental Leadership through Flare Optimization and Operations Excellence
Authors: Mukhamedkali Shynggys 
Published: November 2017

Abstract
The objective of this paper is to describe innovative process and tool developed for gas flaring reduction through Plant Optimization in order to meet state regulations.
According to Republic of Kazakhstan Laws, flaring of any substances during oil & gas operational activities needs to be logged and reported. Kashagan Field facilities are extensive, using approximately 260 valves connected to 2 Onshore and 3 Offshore Flare stacks
Over a reporting period, a valve can be opened and closed multiple times. Based on characteristics of the valve (valve type, pressure differences, valve opening percentage), the volume can be estimated for each release of gas (i.e. Flaring Event).
The following are the challenges that NCOC faces during flaring: Reasons for a flaring event need to be captured and the flaring events need to be managed to properly report the Flaring data against license constraints.Estimated volumes should be reconciled with calibrated measurements of total (at Flare Stack) flare volume taken from calibrated meters, entered in Hydrocarbon Accounting System (Tieto EC System).Composition needs to be derived from flare gas sources (valves).
Temperature and Pressure data to calculate Flaring Volumes are taken from Real-time Historian (OSIsoft PI System). This calculated data is reconciled against actual Flare meter value from EC. In the end, we have reconciled actual data for each valve to report to the Government bodies.
Flare events reporting is very critical for oil & gas business due to high environmental impact that costs North Caspian Operating Company N.V. (NCOC) considerable amount of money. Precision and accuracy of flare compositions reporting improves cost effectiveness. In future, this kind of analytics approach can be implemented for surveillance and reporting of another Oil & Gas operations outcome, water usage and disposal.
First Successful Logging Jobs Worldwide with a High-Resolution Logging-While-Drilling Imaging Tool for 8.5-in. Boreholes
Authors: Al-Balooshi M. , Anurag A. K. , Mishra A. K. , Al-Ali A. E. , Hosany K. I. , Al-Jefri G. M. , Sinha R. , Maeso C. J. , Girinathan S. , Legendre F. , Gzara K. 
Published: November 2017

Abstract
Borehole images constitute a rich source of high-resolution geological data about various formations penetrated by oil and gas wells. Interpretation techniques of these images have progressively improved over the years and provide detailed information about formation dips, structure, rock fabric, fractures, and drilling-induced borehole damage. Wireline tools have the flexibility to be used in a wide variety of borehole sizes. In contrast, logging-while-drilling(LWD) tools are designed for particular borehole sizes. A new high-resolution LWD imaging tool has been built for 8.5-in. boreholes. This paper presents the results from two logging runs located in offshore United Arab Emiratescarbonate fields, including the first worldwide logging run of the tool.
Measurements made by this new high-resolution imaging tool are based on laterolog principles for the measurement of resistivity. The tool performs two main types of measurements, including an array of focused resistivity measurements with an axial resolution near 1 in., and an ultrahigh-resolution resistivity imaging pad consisting of an array of eight buttons. This paper focuses on the LWD tool’s imaging section, designed to provide the same volume ofinvestigation as one of the focused resistivity measurements. This design featureresults in measurement calibration confidence with respect to the formation resistivity, allowing for quantifiable analysis of the formation properties using the image data. The data for this first run were acquired during a washdown through a carbonate-evaporite sequence. Borehole deviation was approximately 60° and the mud was a typical high-salinity water-base mud. A suite of wireline data, acquired after the LWD washdown run, includes a pad-based resistivity imaging tool, which allows comparison of thetwo sets of acquired data.
Data from both the wireline and new high-resolution imaging LWD tools were processed and interpreted. Structural and cross-bedded layers were clearly visible on both imaging-type tools. Borehole crossing and layer-bound fractures were also observed and could be quantified from both tools.
Examples show how identifying some featuresis made easier on the full borehole coverage of the LWD images; however, the higher resolution of the wireline tool is beneficial for identifying some textural features. Results from both types of logging tools are presented and the similarities and differences are summarized. Advances in borehole image visualization are also presented as 3D views in addition to cross-sectional views across the borehole, which make visualization of features more user friendly for those not familiar with borehole image interpretation.
Common Pitfalls in Selection of Restriction Orifice for Depressurization of Oil and Gas Facilities
Authors: Wasnik Rakesh , Singh Bhupinder , Singh Harendra , Kamal Faris , Takieddine Ousssama 
Published: November 2017

Abstract
Multi-stage restriction orifices are being increasingly used for Oil & Gas facilities depressurization instead of single stage orifices in order to overcome noise and vibration constraints. These are typically in the range of 0.5 to 3.0 m long considering 6-10 stages used particularly for high pressure depressurization system. However, in reality Multistage Orifices impose layout constraints in offshore installations and especially for congested brownfield modifications.
Multi-stage orifices are used in Gas and liquid service where large pressure drop is required to avoid choke flow condition and cavitation respectively. Multistage orifices help to eliminate noise, vibration in piping due to cavitation and choked flow. During depressurization of hydrocarbon inventory, the flow through the restriction orifice is inherently in choked condition, thus restrict the relieving rate allowing optimized vent/flare system design. Noise and vibration resulting from choked flow conditions can be addressed by piping design or selecting single stage multibore restriction orifice and thereby eliminating the use of a multistage restriction Orifice for depressurization.
Multi-stage restriction orifices are recommended by suppliers wherever pressure drop is exceeding the choked pressure ratio, which is usually the case in facilities depressurization. The number of orifice stages is selected for limiting pressure drop at each stage below the choked pressure ratio. However, multistage restriction orifices application in depressurization service imposes various challenges such as potential blockage in any of the stages due to hydrate formation and draining of residual fluid from the assembly considering its complex geometry. These challenges get aggravated especially for brownfield modifications wherein single stage orifices are replaced with relatively long multistage orifices in existing congested facilities. Single stage orifices fulfill the requirement of depressurization provided piping design addresses the noise and vibration. Even these requirements can be relaxed by considering intermittent nature of the operation and actual operating experience.
NPCC’s experience in many onshore/offshore oil and gas projects suggests that complex designs can be simplified based on better understanding of functional requirements of depressurization in consultation with suppliers. This paper discusses the constraints of installing multi-stage orifices in offshore installations based on examples from recent EPC projects and proposes to adopt simplified, safe and cost effective design. The paper also highlights benefits of conventional single stage orifices for depressurization service.
Main Automation Contractor Concept and Its Future Challenges
Authors: Gazi Islam , Al-Ali Hassan Ahmed , Al-Falahi Ahmed , Al-Shamsi Mohammad Hassan , Khanbooli Mohamed 
Published: November 2017

Abstract
Currently, Abu Dhabi Marine Operating Company (ADMA-OPCO) is developing three new fields. The respective projects or fields are named as A, B, C in subsequent sections of this paper. All three new fields have Main Automation Contractor (MAC) concept which means plant process control and safety systems are supplied by single manufacturer. This paper presents the difference in MAC concept between these projects and proposes an extended MAC Scheme which covers the electrical control system also in MAC scope. The authors predict that merger of process and electrical control system along with most of the subsystems (Packages) into a unified network will be the trend for future green field projects. The paper describes the technical and commercial advantages the proposed scheme can have over conventional MAC philosophy. A section of the paper also highlights the challenges associated for implementation of the proposed architecture.
Underground Storage of Hydrocarbons: Advantages, Lessons Learnt and Way Forward
Authors: Londe L. 
Published: November 2017

Abstract
Underground hydrocarbon storage is a mature technology, born in the early 20th century and very widespread today. The success of this technology lies in its economic efficiency, its safety and, ultimately, its excellent environmental track record.
The market is divided among three techniques: (1) storage in porous media, by far the most widespread technique for storing natural gas; (2) storage in salt caverns, a technique that is suitable for all hydrocarbons; and (3) storage in mined caverns, a technique that is used for liquid or liquefied products.
The market is currently changing. Underground storage facilities are under increasing stress from operators that are seeking to obtain the most from them. Although some storage facilities still have few movements, since they are used for strategic reserves, many storage facilities today have to provide an optimised working volume and higher cycling and deliverability rates than those for which they were created. Monitoring and modelling are helping designers of storage facilities to improve their efficiency. Safety enhancements are the second mechanism by which underground storage facilities are currently being upgraded. This involves design improvements, with the addition of new safety equipment such as fail-safe valves. It also includes the implementation of best practices. Therefore, tools are available that comply with regulatory requirements and meet the economic efficiency needs of storage facilities. The storage facility integrity management system is one of these tools. Diagnosis and tracking of induced seismicity is another example.
Processing and Recycling Drill Cuttings at Source - Technology and Services Adhering to Zero Discharge Legislation
Authors: Pond Robbie , Hinden Pierre-Marie 
Published: November 2017

Abstract
This SPE paper describes ZADCO's reasoning foropting to utilisethe TCC RotoMill® as the proprietary technology at the core of ESNAAD-TWMA's integrated drilling waste management services on the four UZ750k artificial islands in Abu Dhabi. It outlinesthe basis for this conclusion after examining the drilling programme, well profiles and volume of material that would be generated across the long-term drilling campaign. It also outlineshow they could optimizetheir drilling programmes whilst complying with and exceeding regulations outlined by ADNOCthrough the use of this technology.
The paper explains the TCC RotoMill® technology, its fundamental operating parameters and capabilities which areillustrated in the final presentation of data fromthis case study and the field results from this project. The background and evolution of the TCC RotoMill® is detailed from its origins of being created in conjunction with an International Oil Major ahead of regulatory change in the UK (OSPAR convention). The paper will illustrate the evolution of the technology to modern day units offeringthroughput of up to 10Mt per hour of NAF drill cuttings in onshore / offshore locations and latterly, being adopted as a mobile technology servicing the land rig market.
Lastly, the paper outlines the application of this technology on the UZ750k four artificial islands as an integral part of the larger scope of drilling waste management which collects, transfers and contains all of the drilling returns prior to treatment and/or disposal. The solution was developed whereby drill cuttings are contained and treated at source, enabling ZADCO tomeet and exceed legislative parameters. This eliminated the requirement for ZADCO to transport a significant amount of drilling returns offsite, thereby significantly reducing logistics costs and likelihood of environmental or safety incidents.
The success of the project is summarized in the case study data and key facts which outlines the value added benefits of collecting, transferring, storing and processing 1,443,029 bbl. (volumes to date) of drilling returns with no material having to be transferred offsite and sailed via a supply vessel onshore saving approx. 532,896 km of shipping.
By returning base oil to the Company, TWMA has saved ZADCO approximately $12.7m in recovered base oil across the four islands (which is extracted from the drill cuttings using the TCC RotoMill®and transferred back to ZADCO.)