bluuebunny/crossref_metadata_2025_split huggingface dataset:
Successful Multistage, Hydraulically-Propped Stimulation through Gas Lift Completion Leads to Remarkable Capex Savings Offshore
Authors: Chiriac Antoanela Andreea , Saqib Latif , Sauter Jason Patrick , Albu Marius 
Published: November 2019

Abstract
The paper / presentation objective is to describe the achievement of the first gas lift well completed for multistage, hydraulically propped stimulation in a Romanian offshore field. The scope of the paper is to present the challenges and learnings associated with this well concept / design, engineering, modelling, equipment selection, yard testing, final design / program and offshore installation, operation, and results.
Reservoir depletion modelling indicated artificial lift would be required as early as 6 months within initial well start up. In order to effectively optimise production from the well for a longer range of well life cycle, a multi-stage stimulation sandface completion was selected and plans were made to install gas lift equipment during initial completion installation, prior to rig release. To meet the concept requirements, risks were assessed and case histories were investigated / incorporated during the planning phase to ensure reliability of performing high-pressure stimulations through gas lift (dummy) valves.
The material selection and specifications of the lower and upper completion equipment were defined considering:Artificial lift designReservoir characteristics, Casing size, High pressure stimulation, Life of well operations
Equipment suitability and compatibility considerations resulted in a few equipment selection changes, requiring yard trials to define optimum pulling / running tool string components and configurations, which were then applied offshore.
The final upper completion design consisted of gas lift mandrels (Gas lift dummies were replaced with gas lift valves following the HP stimulation), safety valve, permanent downhole pressure gauge and chemical injection mandrel. The lower completion consisted of hydraulic open hole packers, open hole anchor and open-close stimulation sleeves (all HP rated).
Collaboration within the multi-discipline and with multiple service providers was vital in developing the final, tested design and implementation in the offshore well. The current design in the well is showing great benefits in terms of production (a higher rate than expected) and cost (initial completion includes gas lift equipment already available for future potential use). The concept proof is considered to be of great success for upcoming projects and is increasing the confidence of the operator to develop and approach the upcoming wells with multistage stimulation gas lift completions.
This is the first well constructed in Romania that was hydraulically stimulated using proppant through an upper completion already having gas lift capability. A review of literature indicates this is an industry first. The success and communication of this well could provide benefit to the industry and could increase confidence when combining life-of-well requirements early in the well construction process.
Application of Advanced Seismic Processing to Old Seismic Data for Enhanced Fault Plane Imaging: A Case Study from Offshore Abu Dhabi
Authors: Paul Subhrankar , Khakimov Oleg , Barajas Carlos , Miyamoto Hiroki , Almheiri Afra , Mahgoub Mohamed 
Published: November 2019

Abstract
Low fold poorly sampled vintage seismic data often suffers from poor fault imaging. This can have a critical impact on reserve estimation and well planning. Acquiring high density seismic data over producing fields requires overcoming logistic challenges along with additional costs and increased acquisition time. However, advances in seismic processing technology could improve the fault resolution of vintage seismic data in a cost effective manner. This has been proven in a case study from offshore Abu Dhabi.
The presence of strong surface wave energy, resulting from the shallow water environment and near surface heterogeneity, masked events in the deeper part of the section. Poor and irregular spatial sampling caused aliasing of the surface wave. In the vintage processing, strong de-noising was applied to tackle the aliasing issue, which smeared the fault definitions. During the re-processing, a joint low-rank and sparse inversion was applied to regularize and densify the input data to obtain a de-aliased surface wave noise model. Subsequent adaptive subtraction of the noise from the input removed strong surface waves without damaging the body waves.
The stack quality was improved by application of cascaded surface wave attenuation algorithms. Additional five dimensional Fourier reconstructions of the data improved the signal quality. A carefully designed fault-preserving residual noise attenuation workflow further reduced the residual noise content. Automatic picking of key stratigraphic horizons was carried out in order to evaluate the spatial resolution of the re-processing outcome. Sharper discontinuities along fault planes observed compared to the interpretation of the vintage seismic data. Increased confidence in fault interpretation is of value for structural restoration study and further reservoir understanding. In addition, several new, previously not-visible, small fault features were highlighted as evident from volumetric curvature and semblance analysis. They have been effectively utilized in a forthcoming drilling campaign to de-risk well operation.
Multi-dimensional data densification to de-alias surface waves and five dimensional re-construction of the signal proved to be beneficial to enhance the fault features on the poorly sampled seismic data.
Sustaining Crude Quality Specifications by Leveraging IR 4.0 Solution
Authors: Ahmed Syed , Al-Zubail Ahmad , Al-Jeshi Majed , Yousef Khaled , Musabbeh Alya , Mousa Saad , Bukhari Adeeb , Seraihi Emad , Alamri Sultan H. 
Published: November 2019

Abstract
This paper describes integrated solution that leverages Industrial Revolution 4.0 to sustain crude quality specifications for Saudi Aramco supply chain covering more than 50 GOSPs (Gas Oil Separation Plants), Pipelines, and Terminals. Sustaining crude quality specifications such water content (BS&W), salt content, etc. for the Arabian Crudes (Arab light, Arab Extra Light etc.) requires big data analysis across the supply chain. To address this challenge, Saudi Aramco developed a customized solution called Crude Quality Monitoring Solution (CQMS) which leverages 800+ critical data streams every minute (PI values), classifies the data according to the risk level impacting crude quality specifications. Three developed risk levels are leading proactive, lagging proactive, and lagging reactive, each of which has a defined acceptable risk matrix. Each risk matrix initiates automated notifications for corrective actions proactively. Moreover, patterns and operational events can be easily recognized in the solution visually. The paper also describes several examples where the solution notifications have proactively remediated process disturbances by up to 20% at upstream and downstream facilities while ensuring asset integrity. The solution deployment has also substantially improved the operational efficiency across the network by benchmarking critical data streams. Saudi Aramco is continuing to enhance the solution capabilities to ensure maximization of the crude network.
In-situ Pore Plugging Using Nanosilica Based Fluid System for Gas Shutoff
Authors: Karadkar Prasad , Almohsin Ayman , Bataweel Mohammed , Huang Jin 
Published: November 2019

Abstract
A nanosilica based fluid system was evaluated for forming in-situ glass-like material inside matrix for permanent gas shutoff. This novel method involves two steps; firstly, pumping low viscosity aqueous nanosilica mixture into the formation and allowing it to gel up. Secondly, gas production dehydrates nanosilica to form glass-like material inside the matrix. For this paper, a nanosilica-based fluid system was assessed for pumping strategy and performance evaluation.
A nanosilica based fluid system consists of a mixture of colloidal silica and activators. It possesses low viscosity, which assists in deeper penetration during placement. With time and temperature, it can lead to in-situ gelation to form a rigid gel to block the pore space. Gas production can dehydrate nanosilica gel to form in-situ glass-like material inside formation porosity for permanent gas shutoff. The nanosilica based fluid system was optimized using gelation tests and core flooding tests to evaluate its performance under high-pressure, high-temperature conditions. Formation of in-situ glass-like material inside pores was analyzed using a scanning electron microscope (SEM).
The gelation time can be tailored by varying the activator type and concentration to match the field operation requirements. Kinetics of colloidal silica gelation at elevated temperatures showed faster viscosity buildup. Before gelation, the viscosity for the nanosilica based fluid system was recorded less than 5 cp at a 10 1/s shear rate, whereas the viscosity was increased more than 500 cp at a 10 1/s shear rate. Using core flow tests, N2 gas permeability of the Berea sandstone core was completely plugged after pumping the 5-pore volume nanosilica based fluid system at 200°F. During nanosilica based fluid system injection through the core, differential pressure was increased to only 10 psi showing better injectivity. The SEM images showed the presence of glass like material filling the porosity, which showed in-situ generation of glass-like material inside pores.
The nanosilica based fluid system has a low viscosity and can penetrate deeper into the formation matrix before transforming into a gel. Undesirable gas flow can dehydrate nanosilica gel to form in-situ glass-like material inside matrix for permanent sealing. This is environmentally friendly and can serve as an alternative to currently used conformance polymers for gas shutoff applications.
One Plot - Multiple Geotechnical Solutions
Authors: Perumal Kumaresan , Adel Khalid , Al Awadhi Ibrahim 
Published: November 2019

Abstract
Site soil conditions play a vital role in Oil & Gas projects and it has high influence on project viability and cost. Adopting appropriate strategies by evaluating & implementing ideal geotechnical schemes, the construction cost/time can be significantly optimized. This paper presents a case study of recently executed project with similar concerns and discusses the challenges encountered and fit-for-purpose solutions offered catering to various soil types, which resulted in cost optimization and early project completion.
Geotechnical investigation was carried out at site to establish soil strata/characteristics by drilling bore holes at strategic locations. Results revealed presence of varying subsoil conditions across the plot with high ground water table. At some locations, extremely loose soil was encountered at intermediate depths and at other locations soil was highly loose for top 5m depth.
Initially it was proposed to remove top soil for entire area and replace with compacted fill, however was not pursued due to huge cost. By ‘Thinking differently’, a unique approach was devised and ‘fit for purpose’ solutions offering optimum bearing capacity/settlement were provided based on anticipated loads in respective zones.
The plot was divided into distinct zones based on soil profile, type of structures, anticipated loads, allowable settlement, etc., and cost benefit analysis was performed for different geotechnical solutions. Subsoil in large storage tank areas was investigated for settlement concerns under heavy loads and liquefaction potential during seismic event. Due to weak soil, improvement using ‘vibro-replacement’ technique was finalized to preclude excessive settlement.
In areas supporting heavy structures such as tall vessels/rotary equipment/piperack, etc, special pile foundations with optimum depth were decided to limit differential settlement and safely transfer huge loads to firm strata.
State-of-the-art soil stabilization technique using geo-synthetics, which is proven to modestly increase the stiffness of weak soil was employed in areas intended to support moderately loaded facilities. Removal of loose top soil and replacement by ‘Engineering Fill’ supplemented with adequate compaction was deemed sufficient in certain areas bearing lightly loaded facilities.
By tailoring geotechnical solutions to befit diverse soil conditions, unwarranted/expensive soil improvements & large/raft foundations were eliminated. As a result, foundation footprint/quantities were optimized which resulted in substantial savings in construction cost. In addition, the project was completed ahead of schedule due to elimination of laborious activities.
Common Failure Modes in Oil Flooded Rotary Screw Sour Gas Compressors
Authors: Pallister David , Ong Pang Lin 
Published: November 2019

Abstract
There are many types of equipment failures encountered during the operation of oil-flooded twin screw natural gas compressors. Defining the failure modes of gas compressors mining sour gas is of primary importance for improving reliability. The failure modes for compressors operating with hydrodymanic journal bearings are different from compressors operating with rolling element bearings. Gas compressors operating in corrosive environments easily succumb to failures such as corrosion-pitting, hydrogen-assisted fatigue and chemical attack. Some common failure modes will be defined for each type of bearings used in rotary screw compressors. Identifying these failure modes assists in defining the problem so that new lubricants can be designed to extend the working life of the compressor.
The failure modes of roller bearing equipped compressors operating in sour and acid gases are primarily due to premature spall formation from hydrogen-assisted fatigue (i.e. hydrogen embrittlement) and sulfide stress corrosion. We have found that hydrodynamic journal bearings equipped compressors operating in sour gases will fail due to sulfide corrosion attack of the hydrodynamic bearings. A new additive system was developed to inhibit both types of failure modes. Laboratory corrosion tests were used to compare corrosion inhibition of new additive system to well-established compressor lubricants. When levels of corrosion inhibition were established, the experimental lubricants were field tested. Field tests of this experimental lubricant were carried out in compressors operating with both hydrodynamic bearings and rolling element bearings. The testing in this difficult natural gas field, demonstrated that CPI’s new experimental fluids have extended the operating time to failure, for compressors operating with both type of bearing systems, from about 2,000 hours to well over 10,000 hours. CPI has developed lubricant solutions that improve the reliability by extending the time to failure for oil-flooded twin screw compressors mining water-saturated natural gas streams with both acid gas and sour gas elements.
Using Depositional and Petrographical Rock-Types to Define Hydraulic Rock-Types - A Case Study from the Permian-Carboniferous Unayzah Formation, Offshore Abu Dhabi
Authors: Silva Gonzalez Patricio , Fernandes Melissa , Siddiqi Saad , Hannon Loay , Steiner Stefan , Chitrao Amogh 
Published: November 2019

Abstract
Rock typing represents an important tool for classifying clastic reservoir rocks, especially in reservoirs showing low permeability and low porosity values. For this study we first approach these challenges from a geological perspective and subsequently translate the results of traditional facies and RQ analysis into rock types by integrating previously obtained results with mercury injection capillary pressure (MICP) data. The rock typing workflow proposed by Rushing et al. (2008) is applied to the low porosity-low permeability Unayzah Formation penetrated in three offshore wells, UAE. The characterisation of this type of low reservoir quality (RQ) rock confronts the geologist with some challenges.
The Unayzah Formation is an important clastic reservoir unit in the Middle East, especially in the UAE. It is characterized by low porosity and low permeability values and therefore, according to Holditch (2006) can be classified as a tight gas reservoir where a tight gas reservoir is "a reservoir that cannot be produced at economic flow rates nor recover economic volumes of natural gas unless the well is stimulated by a large hydraulic fracture treatment or produced by use of a horizontal wellbore or multilateral wellbores". In order to characterize the Unayzah Formation we used newly acquired geological and laboratory data obtained from detailed core description, facies, petrographic- and reservoir quality analysis. In a second step we translated these geological laboratory related data into rock types by integrating these data with MICP data considering pore throat geometries for a more accurate reservoir quality characterisation of the Unayzah Formation.
A Systematic Approach to Design and Development of a New ICD to Minimize Erosion and Erosion-Corrosion
Authors: Woiceshyn Glenn , Dikshit Ashutosh , Hagel Liam 
Published: November 2019

Abstract
To prevent or minimize problems associated with water coning in horizontal oil producers, inflow control devices (ICDs) are installed along the wellbore to better equalize the toe-to-heel flux. Nozzle-based ICDs are popular because they are: 1) easy to model accurately, 2) virtually viscosity independent, and 3) easy to install at the wellsite with many unique settings. Nozzles can be installed either in the wall of the base pipe (radial orientation) or in the annulus between the base pipe and housing (axial orientation). The advantages of the former are: 1) smaller max running OD, and 2) no need for a leak-tight, pressure-rated housing. One disadvantage is the high exit velocity that raises concern of erosion or erosion-corrosion of the basepipe.
To overcome this disadvantage, a new nozzle had been developed with a novel geometry that reduces the exit velocity about ten-fold compared to a conventional nozzle for the same pressure drop and flow rate. Computational fluid dynamics (CFD) was used to first fine tune the design to meet strict erosion-corrosion prevention requirements on the wall shear stress downstream of the nozzle for both production and (acid) injection directions, and then to develop flow performance curves for four different nozzles "sizes" that vary in their choking ability, thereby allowing many unique settings per joint at the wellsite.
Full scale prototype manufacturing and flow loop testing were then performed to validate the CFD flow performance predictions and to demonstrate mechanical integrity and erosion resistance for high rate production and injection. The results, as presented herein, demonstrate a robust and commercially viable ICD design that: 1) has predictable flow performance using CFD, 2) minimizes erosion and erosion-corrosion in either direction, 3) minimizes running OD, 4) simplifies the housing design, and 5) allows easy installation at the wellsite with 34 unique settings per joint. Also discussed are two new advantages over other ICDs that were not anticipated in the original development.
Field Experience on the Design and Operation of Mid-Water Arch MWA in South China Sea
Authors: Mohd Zain Zanussi , Fontaine Emmanuel , Abdul Hamid Saifulbahari 
Published: November 2019

Abstract
This paper reviews the current industry practice for the design of Mid-Water-Arch (MWA) including the guidance from International Standards, requirements from Class, engineering (EPC) installation (OIC) practices. Best industry practice has been developed by MISC Berhad based on the past experiences and leasons learnt , to ensure the continuity of operations and prevent production loss through immediate mitigation actions, efficient repair strategy and minimum requirements for new design. The benefits of establishing of a minimum size of tether chain and the implementation of backup tether interventions are emphasized. The information provided in this paper may provenly useful for Class to amend mooring guidance to account for specific technical requirements for MWA long term requirement.
Assessment of Fishbone Well Design Performance in a Tight Carbonate Compared to Single Extra-Long MRC Lateral
Authors: Alyan Mohand , Al Sowaidi Alunood 
Published: November 2019

Abstract
A reservoir simulation study of different fishbone well designs performance compared to a base development well design of extra-long maximum reservoir contact (MRC) single lateral wells is presented. The objective is to compare different well design concepts in a waterflood recovery scheme to achieve production target rate and maximize resource value for economic development of an undeveloped tight carbonate reservoir. The studied reservoir is located in a giant offshore oil field in the Middle East and was used as a representation of the different tight reservoirs within the field. It is characterized by poor quality rocks with a permeability trending from 2 – 0.5 md in a SE – NW direction.
The study compromises an assessment of the achievable initial maximum oil rate, volumetric reservoir sweep and expected ultimate oil recovery factor for different well design concepts for a base short well spacing utilized for effective pressure support. In addition to that, the impact of fishbone well design on well count reduction potential utilizing twice the base short well spacing compared to single lateral wells development design utilizing the base short well spacing was evaluated.
A sector model with equal producer to injector ratio was used with refined gridding to wells and bulk area gridded with a cell size of 10 m by 10 m in a representative area of the reservoir. The modeled wells incorporated with vertical flow performance tables with gas lift capabilities. The analysis also incorporated generating streamlines for analyzing fishbone well designs areal reservoir sweep and an examination of remaining movable oil areal distribution. An assessment matrix was formulated for comparing extra-long MRC single laterals base development design versus different fishbone well designs. The assessment matrix incorporated in addition to reservoir related flow performance indicators: drilling complexity and well cost, well life cycle activities, etc. for a comprehensive assessment.
The main findings show that fishbone well designs have complicated areal sweep performance, especially with sealed motherbore, that result in a lower oil recovery factor with higher hydrocarbon pore volume injected and water oil ratio compared to extra-long MRC single laterals. Also, fishbone well designs have serious limitations during well life cycle activities compared to extra-long MRC single lateral design in terms of stimulation, well accessibility and well intervention options making the extra-long MRC single laterals the preferred field development concept within tight reservoirs especially with the base short well spacing. Finally, the analysis has shown that Fishbone well designs can't reduce the well count since base short well spacing is still needed for effective pressure support by water injection in addition to maximizing the oil recovery factor within the field life time and building and sustaining the target plateau.