bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rectifying the Inherent Compressor Control Issues Using Dynamic Simulation
Authors: Nalagatla Vijayakrishna , Al-Kalbani Haitham 
Published: November 2017

Abstract
A dynamic study was performed to evaluate the proposed compressor control scheme (migrating from the existing standalone compressor vendor control scheme) for the existing propane compressor system. Dynamic study was required as the system included complex compressor controls. It was intended that the inherent control design issues could be identified with the dynamic simulations before implementing the complex control designs in highly critical compressor.
The main objectives of the dynamic simulation were to: Confirm the control scheme and it's transient responsesConfirm the anti-surge / capacity control system designConfirm the control and trip set points
The study included building a dynamic model (using Unisim dynamics) of the relevant process equipment in the propane compressor loop, and subjecting it to transient conditions to evaluate the control scheme.
The main conclusions / recommendations of the study were: The proposed control scheme was able to maintain a constant desired suction pressure while keeping all other controllers in the compressor loop stable and ensured that the compressor operate with a safe margin from surge during normal operating conditions.During the turndown, frequent oscillations were observed due to the antisurge parameter oscillations. This was mainly due to the opening of the quench valve and atomization valve by the temperature controller during hot recycle and subsequent closing of atomization valve. This could have led to the damage of the compressor in the longterm. To avoid, it was recommended to change the control logic such that the atomization valve to close only (once opened) when operating point reaches to right side of the surge control line with sufficient margin.
Based on the above recommendations, the proposed logic was implemented in the plant successfully. Turndown operation is stable and no oscillations are observed. Hence it is recommended to carry out dynamic simulations to verify such complex and critical compressor control schemes to prevent any control issues and long term integrity issues with compressors.
Geomechanical and Thermal Dynamics of Distributed and Far-Field Dielectric Heating of Rocks Assisted by Nano-Enablers — A Numerical Exploration
Authors: San-Roman-Alerigi Damian P. , Han Yanhui , Othman Haitham , Batarseh Sameeh I. 
Published: November 2017

Abstract
Thermal methods based on dielectric heating are of interest in several stimulation and production applications; however, most downhole fluids and rocks have uneven electromagnetic absorption. A potential solution is to create particles that can act as centers of electromagnetic absorption. These are known as enablers. In this technique, the rocks and fluids are not directly heated by the electromagnetic radiation; rather the enablers absorb the electromagnetic radiation, transform it into heat, and warm up the formation and fluids. This paper presents the numerical characterization of the thermal and geomechanical dynamics in this process as a function of different rock types and varying enabler distributions.
The numerical analysis explored the dynamics of high-power electromagnetic radiation (HPEM) and revealed key optimization variables and interactions. The results provide new insights about the relations between the competing physics, and suggest how to control the coupling dynamics to enhance different applications. Ultimately, the techniques and results detailed in this work could prove essential to optimize the next generation of electromagnetic heating and recovery methods.
Thermal and geomechanical modeling showed that the sudden increase in temperature across multiple points, could be used to enhance fracturing and induce other mechanical changes in the formation that are valuable for stimulation of tight formations. A comprehensive statistical analysis was used to determine key variables and optimal heating dynamics, as a function of volume and spatial distribution of enablers. It was observed that the efficiency of the energy transferred to the formation, depends on the volume and spatial distribution of the enablers within the rock matrix. The latter suggests that micro- and nano-particle size enablers could potentially improve heating and energy transfer for oil and gas applications.
New Method of Improving Formation Evaluation in High-Angle or Horizontal Wells Using Image-Constrained Inversion
Authors: Syofyan S. , Hanif M. S. , Latief A. I. , El Gazar A. L. , Al-Shabibi T. A. , Boesing D. , Deng L. , Fernandes W. , Soliman A. M. , Smart C. 
Published: November 2017

Abstract
The Archie equation is the most common approach for calculating water saturation. The true formation resistivity that is derived from resistivity logs is an important component. In high-angle or horizontal wells (Ha/Hz) the commonly employed induction style tools and multi-propagation resistivity (MPR) tools employed in logging-while-drilling (LWD) have challenges. In particular, at bed boundaries, the formation-to-wellbore geometry affects deep-reading logs and generates artifacts such as so-called polarization horns on the logs. These effects become more significant with increases in the relative dip and the resistivity contrast between the beds. These conditions impair the use of resistivity for water saturation determination. An innovative modeling workflow to generate a true formation resistivity (Rt) from LWD MPR logs is presented. In addition, a number of case examples from Abu Dhabi reservoirs are portrayed.
The workflow described in this study begins with the interpretation of borehole image data to build a structural earth model. For this, the picked boundaries are extended away from the trajectory within an investigative volume of the MPR responses and are used to constrain an inversion algorithm that solves for Rt. The inversion is conducted using eight short- and long-spaced apparent phase differences and attenuation data. Different starting models and inversion constraints are applied to evaluate the sensitivity of the inversion results. The inversion results are further qualified from the ‘misfit’ calculated by the inversion algorithm.
This methodology was used to process data from multiple wells in a development field near Abu Dhabi. These high-angle wells are from carbonate reservoirs with varying characteristics (such as tight, layered, high-permeability streaks, etc) and all employ LWD measurements. The integrated data of vertical wells formation evaluation, dean stark and dynamic data (well test) were used to validate results of the case study.
The processing results showed significant improvement in determining true resistivity that provided highly coherent saturation determination along the entire wellbore profile. It gave confidence in the effectiveness of the approach for an improved quantitative petrophysical evaluation in Ha/Hz wells.
This new processing method is able to solve the existing issue associated with LWD measurement in high angle wells thereby improving the saturation calculation significantly.
Feasibility and Influencing Factors of Oil Tolerant Nitrogen Foam on EOR Effect in the Fractured-Vuggy Carbonate Reservoir
Authors: Su Wei , Hou Jirui , Zhao Fenglan , Xi Yuan , Zhao Teng , Ding Baodong 
Published: November 2017

Abstract
The purpose of this paper is to research an oil tolerant foam agent as a displacing phase to improve oil recovery in the fractured-vuggy carbonate reservoir. The foamability and foam stability were tested to optimize the concentrations of the foam compositions, and its static performance was analyzed in the presence of crude oil. Meanwhile, a visualized fractured-vuggy physical model was designed and fabricated based on the geological condition of well S48 and well TK467 in Tahe oilfield, West China. The residual oil type and distribution after bottom water flooding in the visualized model were firstly summarized. Secondly, dynamic production performances of N2 flooding and oil-tolerant N2 foam flooding were comparatively studied. Finally, the two primary factors including positional relation between injection-production wells and injection methods were primarily studied.
Results indicate that the foamability and foam stability increase to a constant state when concentrations of surfactant and inorganic salt increase to 0.5 wt% and 0.35 wt%. And the polymer can significantly enhance the foam stability in the presence of oil. The displacing experiments in the model illustrate that the types of residual oil include oil trapped in the closed caves, "attic oil" on top of vugs, by-pass oil that can't be swept and oil film absorbed on the surface of fractures. The oil tolerant foam can stably accumulate in the vugs and expand swept volume due to gas mobility control. A better oil recovery can be achieved in foam injection by means of low positional flooding and high positional production. Besides, the oil recovery with slug foam injection is almost similar with continuous injection, but can significantly reduce the gas consumption.
In Situ Mercury Decontamination for Pipeline Decommissioning in the Gulf of Thailand
Authors: Chanvanichskul Chatawut , Punpruk Suchada , Silakorn Passaworn , Thammawong Chanya , Pornnimitthum Surapol , Kumseranee Sith 
Published: November 2017

Abstract
For offshore decommissioning in the Gulf of Thailand (GoT), Mercury (Hg) has been recognized as a serious contaminant in hydrocarbon streams. Consequently, for PTTEP, as the E&P operator in the Gulf of Thailand, one of the significant environmental and economical issues during decommissioning is the decontamination of Hg in the equipment and pipeline. PTTEP’s decommissioning plan focuses on leaving in situ of subsea pipelines which can be arranged only if Hg contaminated in the pipeline is almost fully cleaned and Hg content is below an acceptable level. Techniques to decontaminate Hg from pipeline and postmonitoring methods are required in the Final Decommissioning Program. Therefore, the research to identify the techniques to measure and remove Hg contents from metal is required. The three innovative steps have been studied including identifying depth of mercury penetration through the pipe surface, developing the technique for in-situ mercury decontamination from the pipeline and finally developing a tool for measuring contaminated Hg content in pipeline before leaving it in situ. According to the study result, the efficiency of the proposed decontamination technique is satisfactory which can remove the major content of Hg in a few hours. In addition, the prototype of tool to measure Hg inside the pipeline was developed and tested successfully. Cleaning process optimization in pilot facilities is currently in progress to finalize the methodology for field application.
The proposed methodology and tools are served as "the World First Methodology and Tools". It is considered as green decommissioning to reduce impact on seabed ecosystem and eliminate pipeline Hg contaminated wastes. Also, it is cost effective and potentially creates a new business opportunity for E&P worldwide.
Machines Performance Algorithmic Modeling for Anticipating Machines Health Using Real Time Condition Monitoring Data
Authors: Almadhoun Wael , Alashqar Ameed 
Published: November 2017

Abstract
Machine Performance is evaluated and indicated by several factors such as vibration, bearing temperature, pressure and flow among other important factors used in machine maintenance and repair decision. The majority of the Gas Turbine condition monitoring system depends on single factor with fixed values to judge the condition of the machine. In this paper the Authors proposed using algorithmic approach to model multiple factors, by developing a model using machine conditions monitoring data to forecast and anticipate the Machin's performance. Following HBR the new Technology Stack for connected smart devices which has three core elements: the mechanical and electrical parts are the physical components; the sensors, control systems, data storage, OS and software are the smart components; and the connection between all parts as the connectivity components. The capability of the connected smart devices can go through 4 Stages (Monitoring -&gt; Control -&gt; Optimization -&gt; Autonomy). The scope of this paper will cover the optimization stage only, but also depends on the monitoring and control stages. The computer systems and artificial intelligence used to build a Machine Learning (ML) model that can predict the machine performance. The predicted results of this model can help operations to take the right decision in an advance proactive steps. The Support Victor Machine (SVM) learning algorithm has been used to training the model based on actual site data. The results of training and test data were accurate. The model which predicts the machine condition/status is promising and will provide the operators and the site engineers with a proactive support tool.
Low Resistivity Pay Identification in Lower Cretaceous Carbonates, Onshore UAE
Authors: Ruiz J. L. , Gohary M. E. , Beshr H. Al , Hosani M. A. , Hannon L. , Rajwade S. 
Published: November 2017

Abstract
The presence of Low Resistivity Pay (LRP) in reservoirs has been widely reported worldwide for both, clastic and calcareous formations. By definition, a LRP is not identified by the resistivity log, as its electrical beam is short circuited by the microporosity water bearing. This effect results in lower responses than expected for the conventional resistivity log, and hence, in higher estimations of water saturation that observed from production data. There are many factors that could create a LRP effect such as water invasion, conductive minerals, fracturing, thin bedding, fresh formation water or rock fabric (i.e. microporosity).
Regarding to rock fabric as driver for the LRP effect, the most common is the presence of the microporosity. This microporosity can be created by diagenetical processes (i.e. micritization) or whatever other component or process which preserves a microporous system inside the total porosity system of the rock. The presence of microporosity in the porous system, as a water bearing system, acts as an electrical shortcut for the electrical current, and it increases the general water content as calculated by the resistivity tool. The result is that SW due to microporosity contributes as Irreducible Water Saturation (SWirr) and not as Free Water Saturation (SW), with a direct effect on reserves assessment (Static Model), but with no significant effect to the field production (Dynamic Model).
The aim of this study is to identify the eventual presence of a LRP, and to determine its origin. By the above, a new fluid saturation assessment was performed based on both, available core and log data, together with a new set of core data focused on the available cored oil wells, in order to identify and recalculate the Gas, Oil and Water saturations for building a the new Static and Dynamic models. The new set of core analysis includes not only Conventional Core Analysis (CCAL), such as air porosity, grain density, Ka, Kk, Kg, CT Scanning or thin sections, but also Special Core Analysis (SCAL) as Mercury Injection Capillary Pressures (MICP) and Nuclear Magnetic Resonance (NMR).
Innovative Approach to Prolong ESP Run Life Using Algorithmic Models
Authors: Shuwaikhat Hisham Al , Ramos Marcelo , Aifan Abdul-Rahman , Al-Sadah Ali A. 
Published: November 2017

Abstract
Over the last few decades, numerous improvements have been made on Electrical Submersible Pumps (ESP) as an economical artificial lift method in the oil industry. However, the ESP reliability has just marginally increased considering the strategic alliances, maintenance fees, driven performances, and production deferrals. Also, the ESP was previously monitored by conventional ways and means (such as frequent and physical well site visits, obtaining ESP related parameters and evaluating the manual amperage (Amps) charts) for the required course of actions after the fact which hindered reaching optimum ESP performance and shortened its run life.
The ESP monitoring and surveillance program has been through several enhancements throughout the past years with an objective of timely maintaining the ESP parameters. Part of this process is the initiation of Artificial Lift Teams (ALT) who are tasked to enhance surveillance program, optimize ESP performance, and enhance the ESP best practices which led to prolong ESP run life.
The ALT has developed an era of optimized methodology and monitoring system that integrates all ESP parameters and variables in an assimilated platform. The system has a capability of a diagnostic process, production optimization, ESP track and trip prediction alert, ESP dashboard with production rates, and field overview in order to decide on the immediate remedial action. This approach acts as a quality assurance system using algorithmic models to proactively predict ESP trip or failure.
This paper will present the innovative methodology, which is being currently used, resulted in optimizing the monthly production, eliminating the deferred production, unifying the operational ESP data, integrating an ESP standalone platform, triggering flags, sending alerts, minimizing ESP downtime, and optimizing ESP maintenance costs. The system led to enhance the ESP daily operations and prolong its run life.
Surface Facilities for a Giant Thermal EOR Project - Cost and HSE Implications of Alternative Fuels for Steam Generation
Authors: Coll R. , Peña G. , Guitián J. , Mancera A. , Escobar E. 
Published: November 2017

Abstract
This paper describes three different surface facility configurations for an Enhanced Oil Recovery (EOR) project in the Orinoco Oil Belt (OOB), where steam-based, thermal EOR processes are planned to be used at a very large scale.
After an initial EOR screening process, four steam-based, thermal EOR technologies werepre-selected as potentially suitable options for the field: Cyclic Steam Stimulation (CSS), Steam Flooding (SF), Steam-Assisted Gravity Drainage (SAGD), and Horizontal Alternating Steam Drive (HASD). In the conceptualization phase, several alternative cases were consideredfor each technology, including variations in injection rates, deployment schedule, and well spacing. All these subsurface cases could be condensed into two design cases for the surface facilities: a low steam generation rate case, and a high steam generation case. However, due to the very large project size and the potential competition with other developments, uncertainty existed about the amount of natural gas that could be available as fuel for the steam generation, as well as about the environmental implications of the EOR operations.
To handle these uncertainties, two alternative fuels were considered in addition to natural gas: coke and extra-heavy oil (XHO); a fourth option consisting in a combination of gas and coke was also included in the study. Surface facilities for the two steam generation rates and for the four different fuel alternatives were conceptualized obtaining class V cost estimates. Environmental impact in terms of CO2 emissions and fresh water demand was also evaluated for all the design cases.
As expected, natural gas is the fuel that leads to lower cost facilities, as well as to a smaller environmental footprint. On the other hand, in the probable case that not enough gas is available, the decision to use coke or XHO as an alternative fuel will depend on the relative weight given to the economic and environmental factors, which are very related to the EOR technology selected for the field. Thus, this work demonstrates how the integration of the surface facility designs with the reservoir studies allows obtaining very useful insights on the advantages, risks and drawbacks of each EOR technology. This innovative subsurface-surface integrated approach sets the basis for high quality project decisions.
Replacement of Critical LP Booster Compressor High-Voltage Motor With Non-Similar Motor for Blower Application
Authors: Rege Atul , Bhat Satish , Al Kazeeri Ahmed , Badawy Ahmed , Surange Vivek , Ramasamy Babu 
Published: November 2017

Abstract
The objective of this paper is to share the successful experience of replacement of failed High-Voltage LP Booster Compressor Motor at Company Operating plant with non-similar blower Motor of different frame size, rating and torque speed characteristics available at different plant in order to minimize the production loss during the anticipated failed motor repair time of 6-8 weeks, and resume the production in less than 3 weeks.
Production loss to the upstream Operating Company (OPCO) due to un-availability of the failed motor was anticipated to the tune of 1.0 MMUSD per day, as LP Booster Compressor does not have stand-by unit.
Based on the criticality and urgent requirements, arduous efforts were exerted by Maintenance, Operation & Engineering teams to select new motor and modify the same to suit the required application.
In-spite of the fact that the short-listed motor to be retrofitted is being dissimilar in many aspects, various options to fit the motor to the existing compressor base frame, machine the motor shaft to couple with the existing gear-box, control the compressor load during starting, increase the prestart voltage to enable motor acceleration and necessary change to the protection settings have been studied and the optimum option from equipment integrity point of view have been selected in-house.
Mitigative pre-start measures were also studied through in-house motor starting studies and recommendations were further implemented at site in co-ordination between End User, Technical team, Compressor OEM and upstream electricity supplier to put back Compressor in service within short span of three weeks.
DigiCoal: A Numerical Toolbox for Fractured Coal Characterisation
Authors: Jing Yu , Armstrong Ryan , Mostaghimi Peyman 
Published: November 2017

Abstract
We present the DigiCoal toolbox that is an integrated set of numerical functions written in Matlab, dedicated to analyse 3D computed tomography (CT) images of coal and reconstructing representative digital models. The design is based on a comprehensive framework: CT image pre-processing, statistics extraction, digital coal modelling and structural analysis. This paper offers an overview of the structure and techniques used in the creation of the toolbox, together with code snippets and examples.