bluuebunny/crossref_metadata_2025_split huggingface dataset:
38 Years of Experience with Seawater Cooling Cu/Ni Tube Bundles in LNG
Authors: Sabry Houssam 
Published: November 2015

Abstract
Many LNG and gas production facilities depend on sweater cooling as a cooling media in its processes. Seawater cooled heat exchangers represent the back bone to achieve the required operations performance. Copper based alloys are the classical material of construction for sweater cooling heat exchangers. Al-Brass, Cu/Ni 70/30 and 90/10 are all copper alloys famous for being used in seawater cooling heat exchanger tube bundles. However, copper based alloys are prone to numerous degradation mechanisms. This paper shares ADGAS’ long term experience with copper nickel heat exchangers in sweater.
The study includes the operations and inspection history of over 100 copper based alloy heat exchangers. It provides the gas and LNG industry with a wealth of information in terms of the observed damage mechanisms, failure history, performance in addition to the operating parameters affecting the integrity of copper based heat exchangers.
The paper would conclude the best performance parameters of these heat exchangers and would provide useful information to establish the optimum integrity operating window for the copper based heat exchangers. The paper would include the performance of all used copper based alloys in terms of Al-Brass, Cu/Ni 70/30 and Cu/Ni 90/10. It will also compare the economics of using copper based alloys versus the use of other materials of construction in the same application like titanium and 6 Moly super austenitic stainless steel alloys.
Little information is available on the long term performance of copper based heat exchangers in the Gulf region waters. Furthermore, it will be an opportunity based on this long service life of 38 years to confirm the published academic literature on the performance of these heat exchangers. The paper shall hence represent a very useful tool for the materials selection in Gulf water cooled heat exchangers.
State of the Art Special Core Analysis Program Design and Results for a Middle Eastern Carbonate Reservoir
Authors: Gao Bo , Kralik Jim , Vo Loan , Shebl Hesham , Al Shehhi Rashed , Al Jawhari Mohammad Omar , Fullmer Shawn 
Published: November 2015

Abstract
A state-of-the-art special core analysis (SCAL) program for a Middle Eastern carbonate reservoir was designed to provide critical and high quality SCAL data for use in field-wide reservoir studies. The workflow for the design and implementation of such a program is described with a specific focus on four key requirements: 1) measurements must be on representative rock samples (the right samples); 2) measurements must be made under conditions representative of displacement processes in the reservoir (the right conditions); 3) measurements must be made using precision equipment and techniques (the right equipment); and 4) trained and experienced technologists are needed to conduct the measurements and model the data (the right people). The scope of the study was unprecedented in size in order to provide sufficient SCAL data coverage for the major static reservoir rock types (SRRTs), wide range of saturation conditions, different fluid systems (water-oil and immiscible gas-oil), as well as recovery processes (drainage and imbibition) encountered in the reservoir. Early engagement between engineering and geoscience disciplines ensured optimized coring and plugging practices for obtaining representative SCAL samples. In particular, a unique twin sample plugging and companion plug rock typing strategy was employed prior to SCAL measurements and was proven to be essential in enforcing accurate and consistent rock type assignment throughout the multi-year program. Continuous alignment with business functions also encouraged program optimizations that better address business needs. Overburden centrifuge capillary pressure and steady-state relative permeability results on native state samples are presented to demonstrate the high consistency and quality of data obtained from a well designed and executed SCAL program. The general trends observed from this expansive dataset, combined with recent advances in carbonate pore system characterization research, have yielded valuable insights into displacement behavior in heterogeneous carbonate rocks. The significant impact of high quality SCAL data on effective reservoir management is also discussed.
Study on Permeability Anisotropy in Carbonate Reservoir Samples Using Digital Rock Physics
Authors: Sun Huafeng , Vega Sandra , Tao Guo 
Published: November 2015

Abstract
Carbonate reservoirs can be extremely complex when estimating oil and gas production due to their texture heterogeneity, mainly from the structure of the pore space. Understanding the flow mechanism in carbonate reservoirs is essential for successful hydrocarbon development and production. Permeability is an important parameter and plays a key role in enhancing production and recovery. However, usually permeability anisotropy is observed due to the deposition, diagenesis, and/or tectonic movements of the rock formations, which complicates the reservoir characterization and description.
The digital rock physics (DRP) following the computed tomography (CT) scan techniques has progressed at a rapid speed since the three dimensional (3D) pore geometry structure of reservoir rocks can be captured and visualized and it is able to compute core sample parameters (such as porosity and absolute permeability) from the digital image (Kalam et al. 2013). To better understand permeability anisotropy in core samples from a carbonate reservoir, some accurate methods in DRP are followed.
In this study, five digital rock samples were selected to do the simulation. For each digital rock sample, in order to reduce the computational cost, three cubic subsamples were selected respectively from the upper, middle, and lower part of whole core plug as digital rock models. Then, the porosity and the absolute permeabilities in three perpendicular directions were computed (one in the axial direction, z, and two, x and y, perpendicular to the axis) in each of these cubic subsamples using the parallel lattice Boltzmann method (PLBM) in the high-performance-computing-cluster (HPCC). The results show that: (1) All the calculated porosities of the subsamples are close to the experimental porosities; (2) the calculated permeabilities in z direction of representative subsamples (Kz) are all close to the experimental permeabilities in the axial direction; (3) for four samples, Kz is much higher than the permeabilities in x and y directions (Kx and Ky, respectively). In other words, both Kz/Ky and Kz/Kx are higher than 1, and Kx/Ky ratios are closer to 1; (4) for only one sample, both Kz/Kx and Kz/Ky are less than 1, which may be caused by some geological structures present in this sample (stylolite); (5) permeability anisotropy in these carbonate samples is clearly confirmed and quantified.
Successful ESP Operation ADCO - SHAH FIELD
Authors: Kannan Jawahar 
Published: November 2015

Abstract
Artificial lift ESP's were installed in ADCO SHAH Field in the year 1994 to enhance recovery and sustain production. As of September, 2015 Shah Field has a total of 60 oil producers with ESP's, mostly characterized by applications with high water cut and low intake pressures. Additional wells are being drilled to enhance production.
High water cut and low intake pressures possessed a challenge, resulting in premature ESP failures thus impacting field performance indicators and cost of work over for ESP replacement.
To overcome these challenges ADCO has adopted optimization strategy to enhance oil production in a mature field by understanding the ESP system & reservoir conditions as an integral unit.
Shah Field has achieved one of the highest ESP run life of more than 15 years (Well no Sy-32 still running) and 6 more wells operating beyond the MTTF indicator. The objective of this paper is to share ADCO's successful optimization strategy to increase ESP life.
Seismic Reservoir Quality Prediction, Khazzan Field, Oman
Authors: Chris Stiteler T. , Sullivan Claire , Kumar Dhananjay , Matthews Samuel , Al Jahdhami Nafa Humaid 
Published: November 2015

Abstract
We present a seismic analysis workflow to evaluate tight gas sandstone reservoirs from a case study of the Khazzan field Barik formation, which is currently under development. The work from this field is particularly important because seismic attributes are playing a critical role in optimization of the field plan, mainly by distinguishing areas of good productivity from poor productivity.
Our evaluation starts with conditioning the migrated seismic data for AVO (Amplitude Variation with Offset) by reducing noise, flattening gathers, balancing amplitude and spectral frequency, and creating intercept, gradient and angle stacks. At the same time, a seismic rock property study is conducted, integrating acoustic well logs, petrophysical analyses and core data to model possible outcomes, and design the offset porosity and lithology volumes from conditioned data.
Then numerous attribute maps are extracted from offset and stack data, including Extended Elastic Impedance maps from offset data and amplitude maps of various types from stacked data. Key attribute maps from stacked data include average amplitude from colored inversion and spectral decomposition over the reservoir time window. After these products are created, statistical comparisons are made between attribute extractions at well locations and porosity-height from petrophysical analyses of logs and core studies. Graphs, statistics and bubble maps of actual and predicted porosity-height are analyzed together to develop preferred predictions showing distribution of uncertainty over the area of interest.
As development of the field progresses, seismic predictions of reservoir quality evolve with new wells being drilled, seismic data being improved and seismic attributes being tested. Initial efforts have already led to the optimization of the drilling schedule by re-scheduling wells from poorer to better areas, and planning for pilot wells to test areas of uncertainty. This seismic analysis workflow aligns with our goal to determine the degree to which seismic can be used to predict reservoir quality and guide field development, when integrated with geology, petrophysics and production data.
Well Completion Challenges in an Extreme Environment: A Case Study of the Design, Material and Completion Equipment Selection Process for Extreme Environments
Authors: Singh Basant Kumar 
Published: November 2015

Abstract
Well completion design is critical for the life cycle of a well. This includes expected loads during drilling, production, and work overs as well as metallurgical compatibility with production fluids. Any failure in the completion has the potential to jeopardize well integrity, delay production and can potentially impact the economics of the field development plan. There are long term studies on reliability of specific type well completion equipment which includes over 30 years of operational experience for well systems. This has provided a comprehensive database on well completion equipment with thousands of well-years of production experience and downhole failures. However, no such data base is available for well completions with high Ni CRA metallurgy for high sour gas field development.
Al Hosn gas commenced development drilling in one of the Southwest sour gas field, located 180 km southwest of Abu Dhabi in 2011. Phase-1 gas wells were drilled and completed in December 2014. The well design is a single lateral, open hole reservoir completion, with the laterals being approximately up to 15,000ft long. The well test data and logs were used to establish some of the completion equipment design parameters including H2S 20–30%, CO2 8–12%, salinity 160,000–220,000 ppm, BHT 275 -325 deg F, FTHT 225–250 deg F.
This paper highlights the work that went into completion design as well as choosing the metallurgy, connections type, elastomers, and the completion components. In some cases, this was the first application of the equipment in such an extreme environment. The process for designing a completion with high Ni CRA Metallurgy included: 1) literature survey; 2) identifying the required standards & procedures; 3) selection of required CRA metallurgies for required grades based on standards; 4) CRA vendor prequalification; 5) validation of all CRA metallurgies by lab tests for required conditions; 6) selection of connections; 7) validation test for CRA connections; 8) input from other operators & equipment providers; 9) strict management of change process for any deviation from specifications; 10) third party QAQC during manufacturing and make up of sub-assemblies. The completion design integrity has been proven under flowing condition during the well cleanups and flow testing on Phase 1 wells.
Land Data FWI: Methods and Strategies
Authors: Zhang Wei , Dai Nanxun 
Published: November 2015

Abstract
There have long been attempts to apply Full Waveform Inversion (FWI) to land data sets because it has the potential to build higher-resolution velocity models compared to traditional ray-based model building techniches. However, several difficulties hinder the successful application of FWI to land data: cycle skipping, unreliable amplitudes, as well as source and receiver signature estimation. To address these issues, we have developed three new FWI methods: the Dual Frequency Phase Difference (DFPD) Laplace Fourier domain FWI, Surface Offset Gather Flattening (SOGF) Wave Equation Migration Velocity Analysis (WEMVA), and Seismic Reflection Slope FWI. The Dual Frequency Phase Difference (DFPD) Laplace-Fourier domain FWI greatly simplifies the input data and promises the global minimum, and thus, is ideal for initial velocity model building. The Surface Offset Gather Flattening (SOGF) WEMVA method aims at maximizing the flatness of surface offset gather, which is a better objective than maximizing the focus of subsurface time/spatial lagged gather in terms of handling models with large lateral change. The Seismic Reflection Slope FWI method is capable of identifying small velocity anomalies such as gas clouds and faults, thereby producing a higher-resolution velocity model. Three model data examples are used demonstrate the capability of our methods: first we use a simple two-layer model to demonstrate that the Dual-Frequency Phase Difference (DFPD) Laplace-Fourier domain FWI is indeed immune to cycle skipping; second we use a steep boundary model to demonstrate that our Surface Offset Gather Flattening WEMVA is efficient at handling models with large lateral velocity change; finally we use the BP 2004 benchmark model to demonstrate the Seismic Reflection Slope FWI method is capable of identifying small velocity anomalies. We also note that these three methods can be combined together to form a FWI based model building strategy that produces high-resolution velocity model for land data set. Two field data examples are used to illustrate the effectiveness of this model building strategy. First, we applied the strategy to a 2D field data set acquired in Inner Mongolia. Two starting models were used, one is a simple model converted from time domain RMS velocity, and the other is from the traditional ray based model building approach. For both cases, our strategy was able to greatly improve the velocity model and the migration image. The migration image starting from the traditional ray based model had a superior focus and better followed the geological setting, indicating that our FWI strategy is compatible with traditional method and that, in order to get the best possible result, one would use our strategy subsequent to utilizing the traditional method. We then demonstrated this by applying our refined workflow to a 3D field data set acquired in the Pre-Caspian Basin, Kazakhstan, producing a velocity model with an improved migration image, containing fine details such as faults and channels.
Development of a Sweep Pattern Map for a Giant Carbonate Reservoir
Authors: Igogo Arit , Nzimako Uzoamaka Audrey , Khan Sara Hasrat , Al Blooshi Mariam Yousif , Al Shabibi Tariq Ali 
Published: November 2015

Abstract
For giant fields where potentials exist for further oil development, producing companies often step up developmental activities by drilling infill wells and carrying out reservoir monitoring activities to maximize the economic ultimate recovery. This would entail identification of bypassed oil, thief zones, and EOR opportunities. To ensure success of any drilling program or EOR scheme, a good understanding of the sweep pattern of the reservoir is imperative.
This paper highlights the utilization and integration of static and dynamic data for the development of a sweep pattern map for a hydrocarbon reservoir.
To develop the sweep pattern map, the reservoir was discretized based on the development regions and characterized based on results from cased hole logs (RST, PLT), open hole logs well production and injection data. The sweep pattern map was then developed by integrating all the available data and using cross section analysis of wells in each region to define the drainage pattern in that region.
This sweep pattern map gave a clearer picture of the current fluid distribution in the reservoir and this was used in locating zones of bypassed oil, identifying and evaluating potential EOR pilot schemes. Finally, the sweep map was compared with the fluid distribution from the dynamic model and it was found to be consistent.
New Possibilities in Gas Explosion Blast Wave Risk Mitigation in Critical Infrastructure Buildings
Authors: Paappa J. , Ronkainen J. 
Published: November 2015

Abstract
One of the main safety issues incorporates the risk of gas explosion. Active safety measures have been developed to prevent the incidents from leading into gas explosions. Though progress has been made, high overpressures associated with the gas explosion have still remained challenging. Lack of feasible solutions to protect the building ventilation openings from overpressures higher than 0.3 bar (4.4 psi) have resulted in designers trying to cope with the risk with plant layout design and forcing safety specialists to accept the risk to a certain degree.
Advances in gas explosion simulation have made it notable that blast wave will enter the reinforced building even from a small opening in a wall, typically an air vent. Even placing the air vent outside the line of sight of the blast wave will not solve the problem due to complex propagation and reflection pattern of the blast wave. Also manifestation of high overpressures has become more evident.
This paper discusses the various new possibilities offered by blast protection products for higher than 0.3 bar overpressure and multiple consecutive explosions protection. Attention has been given to the protection of ventilation openings in buildings as sufficient mitigation of explosion risks is required in order to sustain the operability of critical functions in emergency.
Design and Implementation of Low Salinity Waterflood in a North African Brown Field
Authors: Callegaro Chiara , Bartosek Martin , Nobili Marianna , Masserano Franco , Pollero Marco , Baz Doaa Mousa , Kortam Mostafa Mahmoud 
Published: November 2015

Abstract
The whole industry seeks to extend the economic life of existing brown fields, due to the difficulty of discovering new giant assets. The efficiency of mature waterfloods may be drastically improved by means of new technologies in order to recover a significant amount of unswept oil. IOR and EOR processes were investigated to increase oil production in a giant brown field in North Africa, developed by means of peripheral sea water injection. Current water injection scheme shows not optimal sweep efficiency and moderate recovery factor due to geological heterogeneity and unfavorable mobility ratio. This work describes the efforts to maximize water injection efficiency by means of the combination of different IOR and EOR techniques with focus on low salinity water.
A dedicated plan to enhance water injection was implemented considering the following pilots: a) water conformance by Thermally Activated Particles (TAP) tested in 2009 and extension planned 2015; b) polymer flooding started in the second half of 2015; c) Low Salinity (LS) water flood planned for 2016. In addition, the combination of the above technologies is under study and will be further evaluated based on the results of pilots.
LS water benefits were investigated within a comprehensive EOR study. First, tertiary corefloods on porous media were performed, showing an evident EOR effect compared with sea water, in increasing the oil recovery up to 7%. Modeling and uncertainty quantification studies showed that LS water may have a significant potential and can be synergically combined with polymer injection to maximize production. A sequence of Single Well Chemical Tracer Tests (SWCTTs) was performed in the second half of 2014 to quickly evaluate LS performance at the well scale resolution. Cycles of injection, shut-in and production periods were performed on a selected well to measure the residual oil saturation (Sor) after sea water and LS water. Promising results were achieved for LS, showing a considerable reduction in residual oil, of about 5-11 saturation units (s.u.) compared to sea water. The SWCTTs were used as a powerful tool to achieve a quick EOR response and confirmed low salinity potential.
The next phase foresees an interwell pilot to test the technology at a larger scale, whose design is currently ongoing. Moreover, the opportunity to optimize the existing polymer injection in a Low Salinity Polymer (LSP) treatment is under study to increase production and reduce project costs.
Acid Systems and ICD Design Considerations For Stimulation
Authors: Edmonstone Graham , Jackson Alfred , Kofoed Curtis , Shuchart Chris , Troshko Andrey 
Published: November 2015

Abstract
The recent industry development of drilling ERD wells with horizontal laterals in the reservoir of 10,000 ft. or more has led to a greater use of passive flow control devices and swell packers to achieve the desired inflow or outflow profiles. Another desire is to perform stimulation treatments of the lateral especially in tight carbonate formations. However, such treatments can create high velocities through the Inflow Control Devices (ICDs) that inevitably leads to high turbulence and wall shear stress in the ICD which can cause severe erosion and corrosion of commonly used materials. There appears to be little experience and associated knowledge on corrosion mitigation to ensure ICD integrity after well stimulation.
This paper will attempt to address such concerns through:
Discussing and analysing ICD design considerations to avoid high corrosion areas and selection of high alloy materials to resist corrosion. Selection of appropriate acid system and method to prevent corrosion. Laboratory testing of acid formulations under high wall shear conditions as predicted from Computational Fluid Dynamics (CFD) of the ICD design at reservoir conditions. Laboratory measurements of the performance of corrosion protection additives in acid formulations under wall shear conditions. Other possible mitigation efforts to reduce the need for stimulation treatments.
Each of these factors presents limitations which either restricts the use of aggressive acid systems or requires alternative acid systems that can lead to increased treatment cost and/or sub-optimal stimulation of the reservoir through the ICDs.
This paper discusses one producing company's effort to systematically improve the overall performance of stimulation through ICDs while maintaining the integrity of the lower completion liner.