bluuebunny/crossref_metadata_2025 huggingface dataset:
Estudio histológico de las prótesis biosintéticas de poli-4-hidroxibutirato (PhasixTM) en un ser humano y revisión de la literatura
Authors: Catalán Garza Vanesa , Peña Soria María Jesús , Sáez Carlin Patricia , García Diego Guillermo , Cabeza Gómez Juan Jesús , Anula Fernández Rocío , Torres García Antonio José
Published: March 2019

Introducción y objetivos: Intentando reducir los inconvenientes asociados a mallas biológicas y a no-reabsorbibles, se han desarrollado recientemente materiales biosintéticos. La experiencia con ellos es escasa y sus características histológicas solo han sido evaluadas en modelos animales.Nuestro objetivo es evaluar, por primera vez, la respuesta tisular al poli-4-hidroxibutirato mediante estudio anatomopatológico en un modelo humano y contrastarla con la animal disponible hasta la actualidad.Métodos: 20 mallas e poli-4-hidroxibutirato (PhasixTM, Bard) han sido implantadas por nuestro Servicio de Cirugía General. Presentamos una mujer de 52 años, quien requirió una colostomía de Harttmann y una laparostomía debido a una sigmoidectomía complicada. En la reconstrucción de la pared abdominal se empleó una malla biosintética (PhasixTM, Bard), por tratarse de una cirugía limpia-contaminada próxima a un estoma, el cual fue considerado posible foco infeccioso. 22 meses después, se realizó la restauración del tránsito intestinal, permitiendo tomar la muestra de pared abdominal que presentamos para estudio.Resultados: No se evidenciaron signos de recurrencia. Macroscópicamente, la malla podía observarse. El estudio anatomopatológico demostró una respuesta inflamatoria a cuerpo extraño. La tinción con hematoxilina-eosina reveló fibras de colágeno maduras y neoangiogénesis, determinando adecuada integración y remodelación tisular.Conclusiones: En nuestra paciente, la malla PhasixTM no se ha asociado a recidiva herniara y se ha integrado de forma similar a lo reportado previamente. El tiempo de reabsorción ha sido mayor, pudiendo favorecer un descenso de la tasa de recurrencia. Los resultados iniciales son prometedores, pero son necesarios más estudios para definir indicaciones clínicas y resultados.
Comparative Analysis of The Role of Gender in Climate Change Adaptation Between Kajiado And Kiambu County, Kenya
Authors: Nunow Abdimajid , Muthama Nzioka J. , Mwalichi Ininda J. , Josiah Kinama
Published: March 2019

Many studies on adaptation to a changing climate have been undertaken across the world Kenya included. However, comparative analysis of gender in relationship to climate adaptation is poorly documented. This study therefore investigated how gender impacts community based adaptation to climate change in Kajiado County, representing mainly pastoral/ASAL regions of Kenya characterized by dry conditions and falling between agro climatic zones IV-VII and Kiambu County, representing mainly farming/highland regions of Kenya characterized by wet conditions and falling under agro climatic zones of between I-III. The study applied systematic random sampling to identify 312 households for interviews. Purposive random sampling was applied where fourteen key informant interviews were done together with six Focus Group Discussions involving three groups of men only, women only and inclusive one to verify information from the individual interviews within the selected communities. The results are comparative analysis of how communities in two different agro-ecological zones (AEZs) adapted to climate change coupled with declining resource base while operating on unequal gender dynamics. The assumption of the study was change in climate in Kajiado and Kiambu County would lead to increased food insecurity and gender disparity. Respondents from both Counties experienced increased drought periods, reduced rainfall patterns thus negatively impacting their livelihood sources. However, there is more gender disparity in Kajiado than Kiambu and also climate change has execrated the situation thus undermining efforts toward food security.
Real-Time Drilling Operation Activity Analysis Data Modelling with Multidimensional Approach and Column-Oriented Storage
Authors: Djamaluddin Basirudin , Prabhakar Prajitha , James Baburaj , Muzakir Anas , AlMayad Hussain
Published: March 2019

Real-time data stream in the format of WITSML which can have frequency as low as 1 Hz is one of the best candidate to produce KPIs for the drilling operation activity. The KPIs generated from this calculation will have a relationship with other information from other data sources, known as metadata.

The question is how can this KPI information be utilized for further analysis, wider/more complex analysis process which needs to be combined with metadata? An OLTP model is not the recommended model for data analytics but OLAP is. Another question is how will this data be stored in terms of the physical storage? We argue to use column-oriented for the physical storage which can perform analytical queries 10x to 30x faster than the row-oriented storage.

The implementation of an OLAP model for storing KPIs data is proven to improve the performance of the analytical query significantly and combined with the implementation of column-oriented in the OLAP model improves more performance. This concludes that the implementation of OLAP with column-oriented data model can be used as the solid foundation for storing KPI data.
Development of a Ceramic Proppant Alternative for Deep Conventional Gas Development in Saudi Arabia
Authors: Fraim Michael , Al-Awaji Saleh
Published: March 2019

The purpose of the paper is to present the results of using local sand resources in Saudi Arabia for the manufacture of resin coated proppant as a ceramic proppant alternative for deep conventional gas development. Crushed Miocene sandstone, old river sand and dune sand has been tested for a source to manufacture resin coated sand proppant. Compared to Northern White Sand in USA, each sand source has its own set of limitations such as angularity, low aspect ratio, clay, carbonate scale or iron oxide coating, and/or micro-fracture damage. Complete resin bonding to the particle surface required clean quartz surface free of sharp edges and no dust contamination. Conductivity testing of the resin coated sand at reservoir pressure and temperature reveals that over 95 wt% of the mesh sized sand particles should pass the room temperature crush test before coating.
Classification and Suppression of Blending Noise Using Convolutional Neural Networks
Authors: Baardman Rolf , Tsingas Constantine
Published: March 2019

Over the last few years, machine learning has become more and more a topic of interest in the seismic industry. In seismic interpretation like fault/salt dome detection (Amin et al. 2015, Guitton et al. 2017) and velocity picking (Smith 2017), there already have been successful implementations for some years now. Recently, machine learning was introduced in seismic processing algorithms like denoising, regularization and tomography (Araya-Polo et al. 2018) as well.

In this abstract a deblending algorithm is proposed that utilizes supervised machine learning algorithms. The method combines the two main functionalities of supervised learning, classification and regression to achieve maximum control on the deblending process. First, blended acquisition and conventional deblending methods are discussed, followed by an introduction to machine learning algorithms and how these machine learning methods can contribute to improve existing deblending algorithms. Finally, synthetic data examples are shown to illustrate the machine learning deblending approach.
A Coupled Viscosity Estimation and Reservoir Simulation for Ensemble Based Production Optimisation
Authors: Almaraghi Bashayer , Etienam Clement , Villegas Rossmary
Published: March 2019

In this paper we carry out a full field Reservoir calibration and optimisation scenario, coupling molecular interactions and ensemble based optimisation techniques. We use the friction theory model to estimate the viscosity, taking into account the molecular interactions and integrating the results in Reservoir simulation using the equation of state. Model calibration is achieved with the Ensemble Smoother with Multiple Data Assimilation (ES-MDA).

Further, we then optimise the calibrated model, focusing on Enhanced Oil recovery technique, with steam injection, utilising the Ensemble based Production Optimisation method (EnOPT). The Hydrocarbons viscosity was estimated using the friction theory, which utilises the attraction and repulsion parameters in a Van Der Waals type equation of state and the concept behind Amontons Coulomb friction laws. The molecular interactions are taken into account in understanding the fluid viscosity behaviour. The link is signified between the molecular interactions and their effect on the velocity between the hydrocarbon fluid layers that are responsible for the resistance to flow. The uncertainty in the estimated viscosity could be narrowed by using Bayesian statistic techniques to match the chosen reservoir parameters with the mean historical data using the Ensemble Smoother with Multiple Data Assimilation (ES-MDA).

The Enhanced Oil Recovery technique was chosen to be steam injection in order to reduce the oil viscosity by raising the reservoir temperature without maximising the overall cost. The Net Present Value (NPV) was maximised by using an ensemble based optimisation technique (EnOPT), where the controls of steam injection temperature and two producers bottom hole pressure were the adjusted parameters.

The viscosity of a heavy oil required additional recovery techniques to increase the driving force for the production. The heavy oil viscosity decreases with increasing temperature due to the increase in kinetic energy of the molecules that weakens the attraction force and the increases in repulsion between them. The initial mean NPV of the generated 100 realisations of the chosen adjusted parameters was found to be approximately $1,500,000.

The mean NPV of the realisations after optimisation was found to be $3,440,056. This increase in NPV was due to the increase in oil production rate, the main parameter influencing the increase in NPV was the cost and amount of oil produced, bearing in mind the water treatment and steam cost. The novelty in this study is a coupling of molecular scale simulation (friction theory) with Reservoir Simulation (by means of the Peng-Robinson Equation of state), which estimates the main physical parameters of reservoir systems and also adequately accounts for the intermolecular forces. We also calibrate the synthetic reservoir model with the ES-MDA infused with EnOPT for realistic model production optimisation.
Acoustic Properties of Carbonate: An Experimental and Modelling Study
Authors: Elhaj Murtada , Abdullatif Osman , Abdulraheem Abdulazeez , Hassan Amjed , Sultan Abdullah
Published: March 2019

The science of Acoustics deals with the propagation of mechanical waves in the three phases of materials, solids, liquids, and gases. In exploration and reservoir engineering, acoustic wave velocities play an essential role in reservoir description. The primary challenge in the initial evaluation and characterization of reservoirs is related to the understanding of its geology, petrophysics, and geomechanics. Therefore, an accurate estimation of acoustic wave velocities and rock porosity is essential for better reservoir description and performance as well as a better forecast of seismic properties. In this reseach, the primary objective is to analyze the texture, mineralogy, porosity and permeability data of outcrop carbonate rock samples to study the impact of confining pressure on wave velocities. Furthermore, an empirical correlation is proposed for relating porosity with acoustic properties.

Ninety outcrops samples are collected from Dam Formation in Al-Lidam area in Eastern Province, Saudi Arabia to develop a correlation. The carbonate samples varies from mudstone to grainstone facies. The samples are collected, prepared, and tested for this experimental study based on API standards. Compressional and shear wave velocities of carbonate rocks are measured under dry and fully brine-saturated conditions for 5 to 25 MPa effective confining pressures at room temperature. Moreover, porosity and permeability are measured using three different techniques, viz., AP-608 Automated Porosimeter-Permeameter, Helium Porosimeter, and thin section technique. Finally, the results are compared with those from other studies related to the same area.

A state-of-the-art review is presented on seismic properties, relationship with porosity and acoustics in addition to the current trend and the future challenges in the area. The laboratory investigations for this study reveals that Al-Lidam area has different types of facies. The results also show that both compressional and shear wave velocities increase as the confining pressure on the dry samples increase. However, the compressional wave velocities increased and the shear wave velocities decreased with confining pressure under fully saturated conditions. A new correlation is presented for carbonate rocks to predict porosity from acoustic wave velocities.

This study will help in improving the exploration efforts as well as give a better explanation for reservoir characterization, facies recognition, geophysical interpretation, and engineering calculations. This attempt will open a new research area for engineers and scientists to study the effect of variation in different properties on wave velocities.
From Pore to Process: Novel Flow Assurance Approach to Suppress Severe Production Chemistry Issues by Flow Dynamic Characterization
Authors: Alwazzan Amir , Dashtebayaz Maryam , Fiaz Mohamed
Published: March 2019

Dragon Oil operates the Cheleken field in the Caspian Sea offshore Turkmenistan. The production system consists of multiple wellhead and manifold platforms, a complex network of infield carbon steel and flexible flowlines to handle production from HP and LP systems and a 30" × 40 km TL to transport the produced fluids to the CPSF (Central Processing and Storage Facility) located onshore. In addition to the complexities of the flowlines network, the development has a number of unique features that pose challenges to the daily production operation activities such as: -Relatively low reservoir temperatures;-Waxy oil with high WAT (Wax Appearance Temperature) and Pour Point;-Complicated bathymetry of the 30" TL (Trunkline);-Complex reservoirs leading to uncertainty in rates;-Increasing water production;-Increasing sand ingress;-Necessity to commingle water from different sources in the flowlines;-Corrosion, erosion and emulsion occurrence;

While management of any of the Flow Assurance issues is well understood on stand-alone basis; there is no definite guidelines to manage them simultaneously through understanding their impact on each other. Obtaining flawless understanding of the nature and extent of each of the impediments issues was a key element for Dragon Oil's team to innovate this approach to minimizing the overall negative impact on production operations. The approach has been developed based on balancing the hydrophobic, hydrophilic and molecular properties of the produced fluids in correlation with the physical criteria of each of the issues to minimize the impact on the others.

This paper presents the key elements of a novel approach developed to control the impact of some issues and maintain the deliverability and integrity of the 30" TL. The approach consisted of the following activities:Conducted thorough and rigorous fluids’ analyses;Generated comprehensive operating pressure-temperature envelop during different operational and ambient conditions in the 30" TL;Constructed the occurrence envelops of Flow Assurance issues focusing on wax deposition and severe slugging;Ensured adequacy of slug catching capability at the CPSF and proper procedures to operate;Controlled gas rates to generate severe slugging in the 30" TL;Monitored the performance of the 30" TL (and eventually the system) through close observations to the changes in the key controlling parameters e.g. pressure drop, outcomes of pigging operations and efficiency of separation.
Modelling Complex Fluid Production Behaviour in a Gas Condensate Field: A Case Study
Authors: Ali Hamza , Shah Abdur Rahman , Akram Agha Hassan , Khan Waqar Ali , Siddiqui Fareed Iqbal , Waheed Abdul , Ahmed Faizan
Published: March 2019

A recent study addressed the modelling challenges of Alpha* gas condensate field. Alpha gas condensate field has a gas in-place of about 1 TCF, and both condensate and black oil production in addition. The field has been producing from two reservoirs S-I and D-I, for the past 26 years. Alpha field is sub-divided into two segments called the Central Area and the Northern Area which are separated by a fault as shown in Figure 2.

* Not its real name.
Application of All Reflectors Auto-Tracking Method to Characterize the Geometry and Distribution of Carbonate Shoals: An Example from the Lower Cambrian Longwangmiao Formation in the Moxi area, Sichuan Basin, Southwestern China
Authors: Chen Xiaoer , Fan Kun , Ren Chenghao , Li Le , Yan Zhenqian , Zou Guoliang , Cao Zhonglin , Zhao Yao
Published: March 2019

The Cambrian Longwangmiao Formation in the Sichuan Basin, southwest China, mainly comprising of dolomites, is one of the most ancient production layer in the world. Recently, Anyue gas field was discovered in the Leshan-longnvsi paleo-uplift in the central Sichuan Basin, and become the oldest gas field in the carbonate rocks in a single structural system in China. The reservoir is mainly distributed in the shoal grain dolomite, which is always controlled by the sedimentary environment. The conventional well correlation and sedimentary facies analysis might result in difficulty of carbonate shoals distribution and reservoir description in the gas field. Hence, how to characterize the geometry and distribution of carbonate shoals is critical for gas exploration and development. In our study, we completed an interpretation of 1172km2 3D seismic data in the field by means of all reflectors auto-tracking method. The method, combining density-based spatial clustering with waveform similarity clustering algorithm, can automatically track and interpret all reflectors within the 3D seismic cube. As a result, 18 local horizons, characterized by a shingled progradational configuration, were recognized within the Longwangmiao Formation. Synthetic seismograms suggest that these parallel oblique progradational sets were considered as carbonate shoals. The Longwangmiao Formation is consisted of stacked multistaged carbonate grainstones deposited on the shoals within the platform. These shoals, which grow towards northwest, are approximately distributed surrounding the Leshan-Longnvsi paleo-uplift. Stacked and widely distributed shoal grainstone reservoir is formed on the uplift. Our study suggests that the paleo-uplift mainly controls the shoal distribution in the study area, which provides important clues for gas exploration.
Gas Lift Optimization of a Mature Field of Upper Assam Basin-A Case Study
Authors: Maut Partha Protim , Changmi Titbo , Chutia Manash Jyoti , Goswami Dilip Kumar , Sharma Manas Kumar
Published: March 2019

Gas lift plays a major role in the oil production operations of mature depleted fields of various E&P companies worldwide. Likewise, in Oil India Limited, India about 48% of producing wells of Upper Assam Basin are on gas-lift assistance. In this project, we have started and completed a gas-lift optimization campaign in Hapjan field, one of the brown fields of Oil India Limited. This project includes complete problem troubleshooting and optimization study of all the 23 gas lifted wells of the mature field.

All gas lifted wells of the Hapjan field are intermittent lift by design and are operating with surface intermitters. As such, all available diagnostic tools developed and available for intermittent gas-lift well optimization are aggressively used during this campaign. The used tools are as mentioned below:Two-pen pressure recordings.Gas volume measurements.Acoustic surveys.Downhole pressure/temperature and long cycle surveys.Revamping of compressor station.

In the present optimization campaign, entire candidate wells of Hapjan field were included and the endeavor has resulted in crude oil production gain of 76 m3/day, which is 11.8% growth of the total production of the field. In addition, based on the results of the comprehensive study of vertical regime of the wells, 3 wells have been taken up for recompletion. Moreover, the gas volume in the injection gas network have been increased from 280000 Scmd to 340000 Scmd with the commissioning of a new compressor, and by revamping of the all other compressor units of the station. This has further supported to reallocate the required gas quantity in each individual well as per the design volume.

The technical experience and knowledge gathered from this gas lift optimization campaign certainly confirms that optimization of gas lifted wells is a vital tool to boost up production in mature depleted fields in Oil India Limited as well as in other exploration and production (E&P) operators worldwide.
A New Discovery in Complex Fault Block Oilfield Based on Dynamic Reserves Study and Fault Sealing Study: A Case Study of Bz29-4 Oilfield in Southern Bohai Bay
Authors: Gao Pengyu , Cao Long , Jiang Cong , Qin Runsen , Cui Longtao , Meng Zhonghua
Published: March 2019

It's difficult to fully discover all the geological reserves during exploration stage, because the fracture system of complex fault block oilfield is very complicated. As the reserve scale in single block is limited, the decline rate of the oilfield is usually very fast. As a result, finding new replacement reserves inside the oilfield is an important method to ensure stable production of complex fault block oilfields.

Base on the improvement of the Vogel method and material balance method to calculate the reservoir dynamic reserves under the degassing conditions of A14 well area. Using Allan profiling to construct lithologic docking relationship between A14 well area and adjacent fault block. Calculate SGR(Shale Gouge Ratio) for different docking areas. According to the statistics of shale content and porosity in the oilfield area, core experiment results with porosity and displacement pressure, the displacement pressure on both sides of the fault docking area can be used to predict the oil column height of adjacent block.

To ensure the initially high-speed production of A14 well area, it's necessary to reduce the times of shut-in static pressure measurement. The continuous reservoir pressure under the degassing conditions is calculated by the improvement of the Vogel method. Avoid the error of dynamic geological reserve calculation caused by too little reservoir pressure data. Result shows that the geological reserves of A14 well area is much smaller than its dynamic reserves. Study on the sealing property of faults around the A14 well area shows that the fault on the east side of the A14 well area is a non-closed fault, and the adjacent fault block is an oil-bearing fault block. Well A20 confirmed the oil-bearing properties for the fault block on the east side of the A14 well area. The result of pressure testing while drilling also shows that pressure drop in the east block of the A14 well area. All of that verify the reliability of previous research.

Aiming at the development of complex fault block oilfield, a method based on dynamic reserves research result to study the sealing property of peripheral faults to predict the height of oil columns in adjacent blocks is proposed. Achieved the purpose of finding new replacement reserves inside the oilfield. The reliability of the research is verified by the pressure testing while drilling. It provides a valuable experience for the development in similar oilfield.
Safaniya Lagoon Corporate Stewardship Biodiversity Sanctuary
Authors: Jumaan Moayad , Alsinan Ali
Published: March 2019

Among the many goals of environmental management in Saudi Aramco, protection of special environmental areas is recognized as high priority to both the company and the Kingdom of Saudi Arabia. In line with this objective, Safaniya Onshore Producing Department (SONPD) designated Safaniya area sea water lagoon as Corporate Stewardship Biodiversity Area. The area is estimated to be 6 km2 peninsula, which is located in the north east of the Safaniya Producing Plant, where undisturbed native flora combines with a pristine shallow sea water lagoon, and provide a safe place for land wildlife (foxes, rodents, reptiles), marine wildlife (turtles, shrimps, fish, mollusks) and birds (flamingos, seagulls, etc.). Establishment of the Safaniya Lagoon started with surveying Safaniya and Tanajib Area, in collaboration with Saudi Aramco Environmental Protection Department (EPD) to select the most suitable region for biodiversity development. An establishment procedure was followed to secure the area with fences to limit the accessibility and prevent improper usage. A signboard was installed to identify the area as a sanctuary, forbidding entrance or any type of land use. Site development included mangrove plantation, already existing trash clean-up, and observation any type of waste dumped in the area, to ensure no contamination or danger to the habitat in the lagoon. The department successfully cooperated with Saudi Aramco EPD to plant more than 9,000 mangrove seedlings at the first two years of development. SONPD in collaboration with Society of Advocates and Volunteers for the Environment (S.A.V.E) invited employees with their respected family members to participate in a biodiversity beach clean-up campaign. The campaign helped collect more than 300 kg of waste, consisting of plastic bottles, old ropes, wood, and other waste materials. SONPD, along with its partners and programs, has now established the Safaniya Lagoon ecological and biological diversity sanctuary as a permanent refuge, with in-place protection and future mangrove planting events planned, the area is expected to expand in biodiversity with native flora and fauna, and expand a natural breeding and hatchery. During the winter season, migratory birds — such as flamingos and Amur Falcons, with flyways that pass over Safaniya Lagoon — are seeking warm weather and abundant food supplies. Creation of biodiversity is just the beginning of further area development. The next phase of sanctuary enhancement will be reutilization of tertiary treated wastewater for trees, which will form a wind barrier for mangroves.
Real-Time Drilling Models Monitoring Using Artificial Intelligence
Authors: Alotaibi Bader , Aman Beshir , Nefai Mohammad
Published: March 2019

In recent years, the Drilling and Workover (D&WO) operations are growing significantly. The growth of active operations required and produced more data from D&WO operations. With very large number of rig activities daily transmitting more than 60,000 real-time data points every second, it became necessary to understand and utilize this Big Data in order to predict drilling troubles and discover hidden knowledge. The adaption of the industrial Revolution (IR) 4.0 contributed to the use of advanced and novel approaches such as Artificial intelligence (AI) and Machine learning (ML) models. However, those models require continues improvement as drilling data change. When using the industrial standard and adapted Wellsite Information Transfer Specification Markup Language (WITSML) based Big Data environment, the task to monitor the performance of a model at a large scale becomes challenging due to common reasons such as a large number of wells, different models being deployed and different data stored in different systems.

In this paper, a new approach is introduced using WITSML based Big Data environment. The methods employed utilize an advanced engine to monitor and evaluate active AI/ML models at a large scale. The engine utilizes anomaly detection methods to monitor abnormal behaviors of the models such as sudden high rate of alerts per day/well or a sudden drop in true event detection. The paper will also demonstrate how such technology can help in early detection of model's decay signs or sudden changes in real-time data quality.

The solution improved and automated the process of monitoring and maintaining of AI/ML models in the Drilling domain. It also made the decay detection of models possible and showed how models improve when iterative enhancements are deployed.
Refrac Screening Processes in Unconventional Reservoirs, A Geomechanics Perspective
Authors: Wang Yarlong , Dusseault Maurice
Published: March 2019

Refracturing is often required in shale and tight gas formations because of inadequate initial HF design or unexpectedly rapid production decline. Water blocking because of fracturing liquid incompatibility, unexpected proppant embedment and crushing, shorter or curved primary fracture length because of premature screen off, general pressure depletion, primary fracture mis-orientation from stress shadowing, unfavourable poroelastic effects limiting the performance of the stimulated volume, and, in general, formation permeability reduction from stress sensitivity may all contribute to unsatisfactory or rapidly declining production. We emphasize the role of geomechanics in candidate screening and review the major factors leading to production decline in unconventional reservoirs. Although the fracture geometry may be altered in a staged fracturing process, the primary focus should be given to the formation permeability enhancement either due to shear dilation or induced fractured network elongation.
Enhanced Hydraulic Modeling and Event Detection Using Real-Time Fluid Properties and Fluid Position Tracking Software
Authors: Porter Aidan , Lie Vivek , Gollapalli Joshua
Published: March 2019

Replicating downhole conditions using real-time software helps reduce nonproductive time. Hydraulic outputs trend against sensor outputs, enabling event detection. Using real-time fluid properties with fluid tracking hydraulic software helps improve predictions for comparison, enabling faster and more reliable detection of downhole conditions.

Two instances of real-time hydraulics simulators capable of tracking property changes of fluid and the positions of discrete fluid volumes within the wellbore were used. One simulator was used with a real-time fluid properties apparatus that provided full six-speed rheology and fluid density in real time. The second simulator used fluid updates provided by the mud engineer on location. The calculated equivalent circulating density (ECD) and predicted standpipe pressure (SPP) from the hydraulics software was compared to actual pressure while drilling (PWD) and measured SPP sensor outputs.

The real-time fluid apparatus provided real-time rheology and density values consistently while drilling the section, and data was provided directly to the hydraulics simulator. Comparing ECD predictions with and without the real-time fluid properties made it possible to identify any improvements achieved using such equipment. Although both sets of data showed that the hydraulics simulator was highly accurate, using real-time fluid inputs enabled ECD predictions to trend considerably closer to the PWD measurements. The capability of tracking the predicted ECD against actual sensor outputs enables users to quickly determine deviations in sensor outputs associated with downhole conditions and to observe deviations occurring as a result of inconsistencies within the fluid system.

Data presented in this paper are taken from some of the first global deployments of real-time fluid properties measurement equipment used in conjunction with real-time hydraulics software.
Is Steamflooding a Form of Low Salinity Waterflooding?
Authors: Al-Saedi Hasan N. , Al-Bazzaz Waleed , Flori Ralph E.
Published: March 2019

Previously, Al-Saedi and Flori et al. 2018d proposed a novel steam-low salinity EOR technique called low salinity-alternating-steam flooding (LSASF) into a reservoir core with a high reservoir temperature. Naturally, if a reservoir's temperature is very low, then oil is heavy. Using thermal EOR techniques in such a low-temperature reservoir resulted in considerable heat loss. In this study, we investigate the steam lifespan from the injector to the producer in order to check if the injected steam is still active throughout the flooding process or if it will condense because of the heat loss. The Bartlesville Sandstone Reservoir, as with other heavy oil reservoirs, is a low temperature (23°C) shallow reservoir containing heavy oil (600 cP). We believe that steam injected into various cores from the Bartlesville Sandstone Reservoir will condense due to the low reservoir temperature. The question is whether or not this condensed steam behave similarly to low salinity (LS) waterflooding.

First, the steam was injected into the oil-free core to determice when the steam condensed and what temperature it condensed at by using a multi-port model to check if the injected steam turned into water.

Several Bartlesville Sandstone Reservoir cores were initially flooded with formation water (FW), and then were flooded with different scenarios of steam and LS water. The temperatures of the inlet, the core, and the outlet were recorded. The effluent was collected from different ports out of the cores and different producer positions in order to follow up the steam position inside the core.

Core contact angle measurements were conducted throughout the flooded cores to determine the wettability alteration between steam and condensed steam (LS water) with the rock.

This study shows that when steam turned into LS water, the sandstone core wettability was altered towards being more water-wet. The condensed steam is considered to be hot LS water, which can reduce oil viscosity and alter the wettability at the same time.

These results were for short length cores. If these results are upscaled up to the oil reservoir scale, then the steam will still be turned into LS cold water (LSCW) as will be illustrated in the analytical model (We are still working on the analytical model). The LSCW will work as a wettability modifier only without reducing the oil viscosity. LSCW is not favorable for use in heavy oil reservoirs because the sweep efficiency is very low due to density differences unless the LS water chemistry is manipulated; however, contact angle measurements showed that the LSCW altered the sandstone wettability towards the neutral wet condition.
Development of an Integrated Monitoring Tool for Oil Field Activities
Authors: Mackenzie G. , Oz O. , Bush E. , Rahimi H. , Janahi M. , Asadalla A.
Published: March 2019

One of the critical processes in managing oil field development is to effectively manage the Annual Work Program and Budget ("AWPB"), a program that contains a company's planned projects, costs, and oil recovery projections, and to execute this AWPB to meet company objectives and goals. Although creating an AWPB in an oil company is a challenge in and of itself, executing the plan with effective control represents a bigger challenge that is the key to achieving success in such a dynamic environment.

To address this challenge with an effective tool, "Tatweer Pulse" was developed as a strategic dashboard that brings the pulse of the field to the decision makers’ fingertips. Tatweer Pulse is a system that monitors the AWPB performance in terms of initiating and tracking field activities, communicating information between stakeholders for effective decision making at any given point, promoting consistency across the organization, improving employee efficiency, and enabling executive management to implement real time planning and change of strategy if needed.

We have successfully completed and tested the pilot phase of Tatweer Pulse, and are currently defining the scope and setting targets for the second phase.
Using Real-Time Data and Integrated Models to Diagnose Scale Problems and Improve Pump Performance
Authors: Al-shammari Baraa Sayyar , Rane Nitin , Ali Shareefa Mulla , Sultan Aala Ahmad , Al Sabea Salem Hamad , Al-naqi Meqdad , Pandey Mukul , Solaeche Fernando Ledesma
Published: March 2019

The Kuwait Integrated Digital Field project for Gathering-Center 01 (KwIDF GC-01) at Burgan Field acquires real-time data from wells and processing facilities as input for its production-surveillance program. Live data from the field is fed into an integrated production model for analyzing and optimizing pump performance. An automated workflow process generates alarms for critical well and facility parameters to identify wells with potential scaling issues. KwIDF workflows are integrated with updated well models to visualize the effect of scale build up on the wellhead performance and thereby assist in quantifying the associated production losses caused by scale deposition. A sensitivity analysis is also performed to identify current and optimal pump operating conditions and prioritize scale cleaning jobs.

The exception-based surveillance of key real-time parameters for wells utilizing electrical submersible pumps (ESPs) in Burgan field has significantly improved diagnostics of scale deposition at wellhead chokes and flowlines. Automated workflows calibrate an integrated production model in real-time, which enables engineers to run a quick analysis of current pump operating conditions and make a proactive plan of action. The application of real-time data and automated models has aided the operator's production team in making informed and timely decisions that enable them to run pumps at optimal operating conditions, with the result that they are able to sustain well production at target levels.

This paper describes an innovative approach to applying real-time data and integrated models in an automated workflow process for enhancing capabilities to diagnose scale deposition in the surface flow network. Examples are presented to demonstrate the application of integrated technology for identifying scaling at wellhead chokes and flowlines and prioritizing a scale removal program for optimizing pump performance.
Real-Time Pore Pressure Prediction in Depleted Reservoirs Using Regression Analysis and Artificial Neural Networks
Authors: Hadi Farqad , Eckert Andreas , Almahdawi Faleh
Published: March 2019

It is known that pore pressure (Pp) is an integral part for the well planning process. Pore pressure can be directly measured from the wireline pressure and well tests, or indirectly measured from seismic velocities, well logs, and shale densities. While the direct measurements are limited due to the cost and time-saving purposes, the indirect methods are often used, especially the techniques that based on the mechanical compaction of fine-grained sediments. However, the loss of porosity in carbonate reservoirs is not only controlled by the effective stresses, but also affected by a variety of depositional environments and diagenetic processes. Most of the previous models were developed to detect the overpressure zones rather than the subnormal (i.e., depleted) zones. There are also some limitations in the traditional methods, as they are based on empirical relations and constants that can differ from basins to others. This study presents a regression analysis (RA) and artificial neural networks (ANNs) capable of predicting the Pp using measurable well logs.

A field case, located in SE Iraq, has been investigated to determine the Pp from well log data. A database for five offset wells of Mishrif reservoir was subjected to the predictive methods. Two traditional methods, the Eaton and the Ratio methods, were also conducted to compare their performance with in-situ pore pressure data in carbonate reservoirs.

The current results showed that the true vertical depth, bulk density, neutron porosity, gamma ray, compressional travel time, and unconfined compressive strength are the key parameters for the Pp prediction. An empirical model with a good performance using ANNs has been developed to estimate the Pp using petrophysical well logs. Although both RA and ANNs are conservative in predicting Pp, the higher value of determination coefficient (0.96) of ANNs demonstrated that the ANN can predict the subnormal pore pressures in carbonate reservoirs. While the Eaton and the Ratio methods which are based on the drilling derived dc values showed a closer alignment with the in-situ Pp direct measurements, they are not applicable in depleted carbonate reservoirs. Other indicators of the prediction Pp should be used in conjunction with penetration rate. The validity of the proposed models was successfully checked with the data from another field study in SE Iraq. This study presents efficient and cost-effective models to estimate the formation pore pressure in depleted carbonate environments utilizing petrophysical well logs.
Coreflood Model Optimization Workflow for ASP Pilot Design Risk Analysis
Authors: Borozdina Olga , Mamaghani Magnolia , Barsalou Romain , Lantoine Martin , Pain Agnes
Published: March 2019

This work presents a new workflow to obtain a better-constrained reservoir-scale model for an Alkaline-Surfactant-Polymer (ASP) injection pilot design. It is explained how the impact of uncertain parameters related to ASP flooding can be quantified, using calibrated core-scale simulation based on experimental results, and how the influential parameters range for future reservoir-scale simulation can be determined. Computational costs of core-scale model are therefore much lower, and the final reservoir model is better constrained.

ASP flooding feasibility implies core scale studies, where chemical formulations are validated in the laboratory under field conditions. In the objective of the pilot designing, a numerical model is constructed and calibrated to history-match the core flood sequences: Remaining Oil Saturation (ROS), surfactant-polymer (SP) and polymer-alkaline (PA) injection and eventually the chase water slug. In order to quantify the impact of ASP chemical parameters on the history match, the Global Sensitivity Analysis (GSA) was performed using Response Surface Modeling (RSM). To obtain the acceptable range of influential parameters for future reservoir-scale simulation, the Bayesian optimization is used.

Applying this methodology on a real reservoir core, the laboratory measurements are accurately reproduced. Nevertheless, once the core-scale model was matched, the transition to reservoir-scale model must be done. Due to a large number of parameters and their associated uncertainties, this transition is not straight-forward. Thus, an additional step in our workflow is included. A new methodology is applied to firstly quantify the impact of uncertain parameters related to ASP flooding (adsorption of surfactant on the rock, critical micellar concentration, water mobility reduction by polymer etc.). To do so, the RSM is used and influential parameters are identified. In this study, the surfactant adsorption coefficients are the most influential parameters while others related to SPA have a poor impact on experiment results matching. Secondly, the acceptable range of influential parameters for future reservoir-scale simulation and feasibility study is obtained during Bayesian optimization. Thus, instead of using a wide (prior) range of uncertain parameters values, refined (posterior) distribution laws can be used for future reservoir model.

While the classical approach consists in matching experimental results to obtain calibrated values of certain properties (that are then entered in the reservoir model) and finally determine the influential parameters at the reservoir scale, here the choice was made to determine influential parameters and characterize their impacts at the core scale. This step helps to better constrain the reservoir model. Ongoing work is using the results of this workflow for pilot design and risk analysis.
Experimental Investigation of Boundary Conditions Effects on Spontaneous Imbibition in Oil-Water and Gas-Water Systems for Tight Sandstones
Authors: Cheng Zhilin , Ning Zhengfu , Wang Qing , Li Mingqi , Sui Weibo
Published: March 2019

As potential alternative resources, tight oil and gas reservoirs are generally exploited with multistage hydraulic fracturing technology to meet the rising demand for energy in the world. Considerable production recovered by the infiltration of fracturing fluids into the rock matrix shows that spontaneous imbibition (SI) is an effective oil recovery method. Through the use of Nuclear Magnetic Resonance (NMR) detection technique, the features of SI in oil-water and gas-water systems for tight sandstones were studied. The T2 spectra of these samples were used to reflect the migration patterns of fluids in various pores under different imbibition systems. In addition, the impacts of the boundary conditions on imbibition outcomes were also determined via the variations in T2 spectra under imbibition stages. The results indicate that tight sandstone samples display the feature of complex pore structure with a wide range of pore size distribution, and the dominant types are micropores and small mesopores. With the progression of imbibition experiments, oil in micropores will be more easily displaced by wetting fluid and flow out through interconnected smaller pores due to greater capillary pressure. The majority of the production through imbibition can be attributed to the contribution made by the micropores. However, water could not enter the mesopores readily under the gas-water system if it is only driven by capillary pressure owing to the snap-off effect of gas. The boundary conditions have notable effects on the imbibition rate and ultimate recovery for the oil-water system and increasing the areas available for water imbibition helps to maintain higher imbibition rate and recovery. However, regarding the gas-water system, boundary conditions have little influence on the imbibition recovery but have a remarkable influence on the imbibition rate. The traditional scaling equations used to scale the imbibition data for both the oil-water and gas-water systems and predict imbibition recovery is acceptable if the wettability of the tight medium remains unchanged. This research aims to uncover the imbibition characteristics of fluids and the nontrivial effect of boundary conditions in tight sandstone samples, which would contribute to the successful development of tight formations.