bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of Acid Fracturing with Unified Fracture Design
Authors: Ravikumar Arjun , Marongiu-Porcu Matteo , Morales Adrian 
Published: November 2015

Abstract
Acid fracturing is the most recognized and successful reservoir stimulation technique for conventional carbonate formations. Resulting fracture conductivity is the key parameter that controls final well productivity, while the competing diffusion and reaction phenomena control the "vital" acid coverage along the full areal extension of the fracture. However, not all reservoirs lend themselves to the same fracture geometry and conductivity, and this is where the "Unified Fracture Design" (UFD) approach is irreplaceable.
Classic fracture design optimization with the UFD approach involves the maximization of well productivity. For any mass of proppant to be injected as part of the treatment, the algorithm determines the unique fracture length and width (with height as a parasitic variable) that will provide the maximum productivity index.
In this paper we recast the UFD approach for specific acid fracturing applications, where the maximum productivity index is now determined as a function of the optimum fracture geometry determined for any volume of injected acid. The optimum fracture width profile is then obtained by solving the convection-diffusion equation for acid propagation, and subsequently used to study the required acid coverage through the fracture as a function of such optimum fracture width profile.
Acid reaction retardation plays a crucial role in ensuring proper acid coverage throughout the optimum fracture length, and this paper focuses on the two major reaction retardation fluid systems: Acid-Internal Emulsions (AIE) and gelled acids.
The workflow presented in this paper provides the basis for designing optimum acid fracturing treatments as a function of the volume of acid injected, the acid injection rate and the selected acid retardation method.
Forecasting the Reliability of a Wastewater Disposal System and Predicting Future Corrective Actions using Hydraulic Simulation
Authors: Al-Hajri Nasser M. , AlAjmi Mohammed D. , Al-Subaie Fehead M. , Al-Zaharani Rashad M. , Al-BenSaad Zakareya R. 
Published: November 2015

Abstract
Continuous monitoring of wastewater disposal (WWD) systems capacities is necessary given the increase in water production from mature fields. The grave and critical importance of such systems necessitates proactive diagnosing and forecasting of WWD system performances. The precise outcomes of hydraulic simulation have proven reliable in forecasting operational scenarios related to WWD systems. The accurate predictions of hydraulic simulation, coupled with identified time frames and monetary investments, pave the way for accountable and successful managerial decisions.
Plant-A injects wastewater into five disposal wells at a given capacity. Historical system performance showed an increase in the pump discharge pressure that has reached near its maximum operating limit. Future production demands entail the need to avail extra injection capacity to this WWD system.
A full system analysis of Plant-A disposal network, utilizing hydraulic simulation techniques, was performed to model the current injection performance. The inflow and outflow performance relationships for five disposal wells were generated and calibrated using actual injection data. Network flow analysis was performed to account for both frictional and gravitational pressure losses in pipelines and flow restrictions using sophisticated software. This comprehensive study of the disposal system was aimed at exploring all possible root causes of the discharge pressure increase. In addition, the hydraulic simulator forecasted several feasible and recommended scenarios to eliminate this high discharge pressure. The contemplated scenarios were tapping into a nearby disposal system (either from the pumps suction or through transfer lines to the close by disposal system) and installing horizontal pump systems at the injection wellheads.
This paper will present in depth the hydraulic simulation results of the above-mentioned scenarios and highlight their feasibility as viable short-term options. In addition, a detailed account of the associated time periods and respective costs of conceived short-term plans is shown. This high accuracy model improved the decision-making process, and an optimized solution was put into effect based on the simulation results.
Optimization of Surfactant Flooding for Carbonate Reservoirs
Authors: Dong Han , Al Yafei Arafat 
Published: November 2015

Abstract
Surfactant injection can be used as an EOR technique by either altering the wettability of reservoir and/or reducing IFT of water and oil. How to balance the functionality of wettability alteration and IFT reduction of a surfactant flooding process for oil wet carbonate reservoirs is still paradox for surfactant technology selection. In this study, the effects of IFT reduction and wettability alteration by surfactant on EOR for a carbonate reservoir were studied by using two kind surfactant systems individually. For IFT reduction surfactant, the surfactants which can reach IFT at different level and ultralow IFT were synthesized based on molecular design method by only changing the structure of surfactant and without any formulation process. Moreover, these surfactants are also has a little effect on wettability alteration proven by contact angle test. The surfactants for wettability alteration study are selected based on contact angle method and also on the principle of "less effect on IFT property". The static and dynamic imbibition tests are carried out to understand the contribution of wettability alteration and IFT reduction mechanism individually to enhance oil recovery, hence, the surfactant flooding technique for an oil wet carbonate reservoir could be optimized.
Optimisation of Shutdown Inspection Activities in the LNG Industry
Authors: Sabry Houssam 
Published: November 2015

Abstract
ADGAS is the pioneer LNG producer in the Middle East. ADGAS owns and operates 3 LNG Trains. Trains 1 and 2 were commissioned in 1977 (38 years ago). Train 3 LNG was commissioned in 1994. Furthermore ADGAS commissioned its first sales gas processing and compression facility (the OAG) in 2010. This was followed by the mega IGD gas processing and compression facility. The ADGAS overall production now accounts for MMSCFD 2100 of processed gas. ADGAS over the years has developed a long term experience in LNG and gas operations, maintenance and integrity management protocols. ADGAS followed a strict Planned Shutdown/Turn Around (TA) at regular intervals for its LNG trains. This paper shares and highlights ADGAS initiatives for optimizing the integrity and inspection related works in its TAs.
TA's are an opportunity to carry out offline maintenance schemes, perform internal inspection for equipment. On the other hand TA's represents a production/ opportunity loss, hence, optimization of TA scope and duration is very important. ADGAS Integrity group has launched a TA optimization exercise. These initiatives included the introduction of Digital Remote Video Inspection, where no physical entry is required to inspect pressure vessels, thus saving time and preparations for physical entry. Another initiative included the introduction of a safe radiography technique. Generally, radiography is done to inspect welded joints. Conventional radiography requires suspension of all TA works and full evacuation from the area. Safe radiography can be done while all activities are ongoing. This introduced a major cost reduction in terms of reducing the TA duration. In Safe radiography the barricaded zone is only 1.5m in radius. Another initiative is by introducing flares online tip inspection using unmanned aerial vehicles. Full and effective RBI implementation has significantly optimized the TA scope of work. This paper and presentation will share ADGAS' LNG experience in TA inspection works optimization.
Lessons learnt, cost reduction and TA scope optimization will all be shared with the audience. The paper would share the lessons learnt from the TA inspection and integrity scope optimization innovative initiatives.
MWD /LWD Challenges and Solutions for Drilling the Longest Al Hosn Gas Well in an Aggressive Subsurface Environment
Authors: Bijjani Patrick , Coscia Marco , Hammon Kenneth , Hoffman Toby , Langson Sidney , Orr Robert , Shah Razza , Amer Reem , Ashraf Muhammad , Hassan Hassan Ali 
Published: November 2015

Abstract
This paper will detail the coordination between multiple teams and across technical discipline groups to successfully drill a +28000 feet (ft.) measured depth (MD) horizontal appraisal well in a high temperature, high hydrogen sulfide and carbon dioxide (H2S/CO2) environment and acquire high quality measurement and logging while drilling (MWD/LWD) data.
Strategic tripping practices were used to reduce the risk of temperature related MWD/LWD tool failures. Extensive fluid engineering work was conducted, to design a fit-for-purpose mud system to meet Al Hosn Gas's handling requirements. Effective surface gas removal techniques were used to preserve high quality drilling mud and insure communication with the MWD/LWD tools. Hole cleaning efficiency was determined and maintained by monitoring drilling trends against calibrated models. In addition, the bottom hole assembly (BHA) drive system was designed to maximize power at the bit.
Specific drilling parameters allowed for a high rate of penetration (ROP) that effectively reduced exposure time of the down-hole tools to very high temperatures minimizing tool failures. Carefully planned fluid engineering provided constant stable mud properties, which allowed the removal of H2S/CO2, and insured adequate borehole cleaning and lubricity to alleviate torque and drag. This resulted in high quality borehole images. Lubricants to reduce torque to manageable levels were selected after exhaustive in-house testing. Similar fluid engineering practices were used to select H2S scavenger. An extension of the horizontal section beyond the directional plan was accomplished within operational limits set by Al Hosn Gas after all drilling risks were fully assessed.
Acquisition of required high quality LWD data was successfully accomplished. LWD borehole images were available only in memory mode, however, azimuthal resistivity curves helped in making geosteering decisions in the absence of the real-time borehole image data. Despite the well being drilled in the pay zone for its entirety, a measurement after drilling (MAD) open-hole log was employed to acquire missing density data that was required after a tool failure. A full petrophysical analysis was completed using the recorded memory data. It was included in the reservoir geo-cellular model and helped to define reservoir properties with a high degree of confidence.
Close collaboration and trust between all partners to continually challenge and redefine perceived technical and operational boundaries led to the successful drilling of Al Hosn Gas's longest well. All teams and personnel were aware of the challenges and developed solutions to acquire excellent MWD/LWD data in one of Al Hosn Gas's most ambitious wells, to date.
Installing Temperature Sensing Fibers into Steel Tubes
Authors: Griffioen W. , Grobety S. , Gapany L. 
Published: November 2015

Abstract
In pipes for oil and gas there is a need to accurately control and monitor temperatures or other parameters. Distributed Temperature or Acoustic Sensing (DTS or DAS) with optical fibers is a technique used for this. In many applications the optical fibres (or small cables) are inserted into small (few mm) steel tubes, pre-installed in or around the pipes. In this paper a technique is decribed where the fibers are floated in with water (or other liquid) under pressure. Optical fibres upcoated to 485 μm have been installed over 3 km with 90 bar water pressure. Higher pressures (and installation lengths) are possible because the fiber pay-off is placed inside a pressure tank connected to the installation equipment. By adjusting the mechanical pushing force exerted on the fiber, it can be installed with extremely low stress.
Excellence in Projects: Path Breaking Approach to Project Management
Authors: Pushkarna A. , Mathew R. , Al-Suwaidi A. S. , Malhotra U. N. , Mukhtar A. , Belbissi F. 
Published: November 2015

Abstract
Organizations are always looking to approach production in innovative ways that will boost the results, increase productivity, cut down slack time and increase revenue while keeping the risks of HSE failures and asset integrity incidents down to a minimum. The challenges are greater when time pressure comes into play. Consequently when an operational rig is shutdown for maintenance it becomes important to execute the project in a shortest time while ensuring uncompromising HSE, Quality and Asset Integrity standards.
NDC examined its practices and put in place an innovative process and named this initiative Excellence in Projects (EiP). Simply put the Excellence in Projects follows the typical path of planning, execution, reviewing, and then once again planning. It follows the classic Deming cycle of PDCA and translates this in project terms.
Starting with an assumption of a "perfect world" with unlimited resources in terms of funds, material and manpower, the EiP allows teams to plan a Perfect Project on paper. The requirement is to come up with a perfect time and quality output – best quality with the shortest time. The output of this ideal project is then transferred into real-life actions taking account of the actual projects constraints. The final result is the happy medium of truly achievable goals against challenging odds. The project is allowed to run and the lessons learnt are captured on completion and feed into the next project thus ensuring a continuous improvement cycle at all times.
This paper is a case study on the successful implementation of this EiP project, using set KPIs and scoring systems, yielding excellent benefits not just in time and cost saving but also Team Building, Quality, Reliability and above all HSE and Asset Integrity.
A Case Study - Achieving Substantive Reduction In Production Downtime During Major Brownfield Interventions On Oil WHTs
Authors: Thallapalli B. , Mukunda V. , El-Sawah M. , Meligy E. , Morakhia Y. C. , Madhi S. A. , Al-Balooshi M. M. 
Published: November 2015

Abstract
ADMA OPCO is burdened with ageing assets and maintaining their integrity is a major challenge. Replacement of subsea pipelines and WHT top side facilities is an ongoing activity, which needs to be carried out without impacting production and compromising safety. The "Portable hydraulic safety shutdown system (HSSS) " is a key enabler in implementing strategies to achieve the desired end results. This is in line with ADMA OPCO's MISSION STATEMENT – To develop oil and gas production to maximize sustainability while maintaining the highest HSE standards". The Portable hydraulic safety shutdown system (HSSS) functionally works as a Wellhead Safety shutdown system in managing temporary modifications to mitigate production losses during Brown field projects. This is of specific importance in a Junction tower, when the concept of "jumper lines" is utilized to continue with the Terminal tower/s production. The jumper line is protected by the Portable HSSS maintaining the availability & reliability of the "Jumper line" Shutdown valves.
Comparing Effectiveness Between Cemented Plug and Perf and Open Hole Ball Drop Completion Assemblies to Ensure Optimal Multistage Fracturing Treatment and Well Performance — Field Examples
Authors: Rahim Zillur , Al-Kanaan Adnan , Al-Anazi Hamoud , Kayumov Rifat , Al-Jalal Ziad 
Published: November 2015

Abstract
Developing gas reserves from relatively tight formations are conducted by the use of a multistage fracturing (MSF) technique that enables maximizing reservoir contact by creating multiple fractures along the wellbore. The key to successful MSF treatment is to generate independent fracture propagation and ensuring the bottom-hole treating pressure (BHTP) is maintained above the fracture closure stress (FCS) also sometimes referred to as the fracture gradient or minimal horizontal stress (σmin), for the fracture to propagate.
Both the open hole (OH) multistage (OHMS) assembly and the cased hole plug and perforation completion (PPC) methods are applied for fracturing horizontal wells. Cement behind the liner in PPC provides excellent seal and isolation between stages that cannot be achieved using either mechanical or swellable OH packers used in OHMS. Failure to maintain complete isolation between stages will not allow stand-alone fracture propagation, thereby reducing the number of originally designed fracture stages. This will reduce contact area and well performance. PPC, on the other hand, depends on manually perforating reservoir intervals and missing the sweet spot due to any misinterpretation of the OH logs will misalign the perforation gun with the reservoir section, thereby reducing reservoir contact significantly, and consequently, gas production.
The OHMS fracturing has proven very effective in the carbonate reservoirs when wells are drilled parallel to σmin and completed with swellable packers. The chances of generating individual fractures are high and the open lateral allows gas flow into the wellbore directly in addition to the production through the induced fractures. The amount of gas flow through the OH section depends on the vertical permeability and how efficiently the near wellbore section is etched and cleaned by the acid pumped.
One type of PPC, where a single interval is perforated in multiple predetermined spots in clusters has proven promising. This will be addressed as cluster PPC (CPPC) in this paper. The short perforated intervals create an orifice pressure drop at the entrance of the fracture during the treatment, keeping the BHTP above σmin, thereby keeping the fracture open. With proper geomechanical modeling, a few perforation clusters can be optimally placed in one interval so that all can be treated by a single pumping stage, with individual fractures growing from each cluster and maximizing reservoir contact. A reservoir simulation performed to prove the benefits of CPPC completions showed that it outperforms the OHMS for a wide range of permeability values. Additional cumulative production varied from just 2% for a good quality reservoir with permeability of 1 millidarcy (md) up to 26% for a tight formation with 0.01 md permeability.
Seismic Imaging in Western Zagros and Impact on Hydrocarbon Exploration: A Case Study from Kurdistan Region of Iraq
Authors: Allouche Hassan , Sapin Francois , Chevallier Bertrand , Cheriyan Thomas , Brosille Eddy 
Published: November 2015

Abstract
This paper presents a case study from Kurdistan Region of Iraq where the integration of a priori geological knowledge (regional understanding based on surface geology, wells) played a crucial role in improving, step-by-step, the quality of the seismic image.
A first well was drilled on the studied structure based on the interpretation of the available seismic. It failed to reach the deep targets. Indeed, the wellbore structural data showed that it was located off structure on its SW flank. These data proved how misleading the seismic image was, and provided new information to the seismic image building process. In the mean time, an infill seismic program whose parameters were designed to better capture the structural complexity was acquired.
The quality of the reprocessed images improved substantially compared to the original data, moreover the newly acquired lines lay one step ahead in terms of seismic quality: Better imaging of shallow reflectors (key for Interpretation in structurally complex environments) and better imaging of steep dips.
Reliable seismic information is key for effective exploration in foothills domains. A reliable image cannot be obtained if the process is not fed with the relevant structural information, and this is equally important at all stages, from acquisition design to imaging parameters. In new exploration domains, such an image cannot be obtained from the first attempt and is not the result of a magic box, but comes as the fruit of perseverance and patient build-up of knowledge. And this requires a closer than ever interaction between the image processor and the interpreter.
The Design and Implementation of a Full Field Inter-Well Tracer Program on a Giant UAE Carbonate Oil Field
Authors: Wang D. , Al-katheeri A. B. , Al-Nuimi S. M. , Dey A. 
Published: November 2015

Abstract
This paper reviews the design and implementation of a full field inter well tracer program of a giant onshore oil field in Abu Dhabi. The field is under peripheral waterflooding in order to maintain reservoir pressure and provide a mechanism to sweep the oil. However, the existence of the strike-slip fault planes juxtaposed across the reservoirs added a variable to the complexity of the waterflood management. In order to improve the understanding towards the reservoir heterogeneity and reduce the uncertainties associated with major faults, a full field water tracer program which is possibly the largest in the Middle East has been designed.
Based on streamline model, unique chemical tracers have been injected in twenty three water injectors covering all the peripheral areas and dozens of associated offset producers across the field were selected to monitor the tracer movement. The program have been designed carefully in terms of tracer selection & compatibility test, chemical volume calculation, injection well and monitoring well selection, as well as the devise of the comprehensive monitoring plan. Ultimately the results of this tracer program will be used in combination with other reservoir surveillance tools to facilitate a better management of the reservoir.
Interwell tracers technology is a valuable tool for reservoir management, however, reliable tracer data can only be obtained through judicious design, implementation and monitoring. The preliminary results from designing the tracer program include: 1) Twenty three water injectors were identified based on streamline modeling for tracer injection and dozens of producers for monitoring. 2) Injected tracers were selected based on the uniqueness, stability, detection limit and environmental friendliness, and compatibility tests were done in advance between tracers and reservoir fluids. 3) Total dilution method was used to calculate the quantity of tracers injected in each of the well. 4) A comprehensive monitoring program was scheduled to capture the arriving of the tracer as well as to depict the entire tracer wave.
The presented full field water tracer program of a giant onshore oil field is possibly the largest in Middle East, and the described designing of the program, encountered problems and best practice could be of some use to those intended planning a tracer project.