bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electric Submersible Pump Troubleshooting Guide, an Effective Way to Improve System Performance and Reduce Avoidable System Failures
Authors: Nunez Walter , Del Pino Jessica , Gomez Sebastian , Rosales Douglas , Puentes Juan , Rivera Hamilton 
Published: July 2020

Abstract
The Oil and Gas industry in recent years have been a great challenge for operators and aervice companies as well. This situation resulted in great opportunities to find efficiencies that can enhancement production, avoid down times and optimize operation in Electric Submersible Pump Systems (ESP). Keeping this on mind, one of the main drivers is implement procedures that can extent ESP run life, and one of the key challenges is to identify any trouble that can impact ESP performance timely so it can implement solutions to avoid failures.
The main objective was to develop a troubleshooting manual that could be used for any engineer to identify likely conditions that could be affecting negatively ESP performance and to implement solutions to minimize failure or damage beyond repair in ESP equipment.
A jointly team composed by the operator and the service company developed a troubleshooting manual to the proper identification of likely conditions that could be impacting the production and performance of ESP systems. This was achieved using monitoring information, tear down evidence, setting configuration and building a database with all the information in order to group similar cases to identify the best ways to respond to any anomaly in ESP behavior.
This procedure was implemented in the field that have an average of 450 active wells with 93% being ESP systems, by socializing it with all the parties that participate in ESP troubleshooting to guarantee a proper handling of any occurrence.
The main purpose of the creation of this procedure was to avoid failures associated with ESP operation conditions that could result in early failure; this is measured with the Failure Index (IF) that means the number of average interventions in an ESP field related to the average number of active wells in the same period.
The implementation resulted in awareness in all the personnel that when best practices are followed there are better chances of field KPI improvements and savings, in this case the Failure Index of the field was reduced from 0.4 to 0.18 attributed to technology and best practices implementation as well.
This paper aims to present the most relevant analyzed cases, the procedures implemented and the results in FI after implementation as well of recommendations to any party interested in implement similar projects in their operations.
Ensuring Zonal Isolation in Cementing Jobs of Gas Well
Authors: Jiménez Edgar , Vásquez Elvis , Velasquez Nelson , Vega Luis 
Published: July 2020

Abstract
One of the critical conditions in cementing operations of gas wells, is the underbalance that generates the entry of preflush in the annular space, especially with the use of in the fluid train, therefore, trying to ensure the pore Pressure control incorporating to the fluid system, only an extensive volume of Spacer.
In this way a possible gas inflow is avoided that would lead to enormous economic losses, however in terms of a good removal, just having a spacer in the preflush system would only be Fulfilling a single function that is the drag of suspended solids. in the annular space without being able to disperse and reduce its solid structures.
Our methodology has been proven in fields with high GOR and good petrophysical and reservoir conditions, which intend to add a volume of washes to the preflush system, thus Hydrostatic Balance with a low Rheological Spacer volume behind the mud.
The preflush system is by batch and pumped at 4.0 bpm continuous, considering a volume of 20 barrel máximum to generate a contact time greater than five minutes, thus improving the conditions of removal, diluting, dispersing and moisturizing the wellbore and casing external.
It evaluates Primary cement Using bond logs that was run three days after the cementing operation. The logging results indicate an average amplitude of around 5 mV, so the 5 ½" in. Casing cement job had 90% average bond index. Good zonal isolation was achieved.
In addition, Mechanical factors such as reciprocating the casing once carried to Depth, and casing centralization with Standoff greater than 80%, guarantee zonal Isolation in the área of productive.
The addition of a Surfactant to the formulation of the washes favors the water wettability of the wellbore in fron of cement.
The use of surfactants in preflushes entrain invading gas downhole and créate a stable foam. This foam then presents significant resistance to flow, thereby limiting upward migration (Marrast et al, 1975).
With regard to the properties of grouts dominate the rheologic behavior, with filtrations less than 50 cc /30 min, and compressive strength greater than 1,100 psi
Foam Cement Proven as Effective Solution for Zonal Isolation in Difficult Wellbores: A Success Field Case in Colombian Mature Fields
Authors: Vela Jose , Arias Henry , Sanchez Edwin , Garzon Juan Ramon 
Published: July 2020

Abstract
The objective of this paper is to present the improvement in zonal isolation and cement sheath properties using foam cement in heavy oil Chichimene Field in Colombia.
Achieving complete zonal isolation in the pay zone have become a major challenge in these fields, recently, given the complexity of the reservoirs: high permeability, low pressure, highly fractured, depleted, low fracture gradient, and cement column for well integrity. Despite advances in drilling technologies, such as MPD, massive losses still represent a major risk both drilling and cementing. Using commonly known cementing methods, like stage tool cementing and conventional slurries, have led to fair results. Foam cement technology emerged as an appropriate cementing method given its great properties both being pumped down, and once set
Foam cement has several advantages over conventional methods: it prevents losses, enhances displacement efficiency in the annulus, provides a unique feature of density/strength ratio, and has improved resilience and elastic properties once set.
Production liners in Chichimene and Castilla field have been cemented successfully with foam cement, even under severe well conditions as partial to severe losses. Full returns have been observed in all jobs while cementing, and cement has been seen at surface after circulating fluids out of top of liner. Good isolation has been obtained as per cement log evaluation. Foam cement has proved to be effective cement method to achieve proper isolation in difficult wellbores and has been of great benefit for cementing production zones in the mentioned fields.
Novelty of the cementing process, described herein, delivers unique engineered features that have proven a major benefit to ensure well integrity in the fields. Cementing under critical wellbore conditions, still account for many costly remedial works, and this novel approach for cementing showed its benefits to achieve excellent results. Content of this paper could benefit many operators dealing with critical wellbores.
Application of the Fast Marching Method in Heterogeneous Dual Porosity Reservoirs
Authors: Nakajima Kenta , Datta-Gupta Akhil , King Michael J. 
Published: July 2020

Abstract
For unconventional reservoirs, the role of accurate reservoir characterization is becoming increasingly important for optimization of field development. The Fast Marching Method (FMM) has provided a novel approach for rapid flow simulation for unconventional fields, as it reduces the depletion in a 3D heterogeneous reservoir model to that of an equivalent 1D model. In this paper, a practical approach to handle highly heterogeneous matrix properties for dual porosity FMM simulation is established. Various averaging methods for the heterogeneous matrix properties are examined through integrated case studies.
Current implementation of FMM simulation can directly account for fracture heterogeneity but requires averaging of the matrix property variations. In this study, we examine the error in the fluid production rate between the 3D heterogeneous reservoir model and the equivalent 1D averaged reservoir model. For some amount of matrix heterogeneity given by the standard deviation of the natural logarithm of permeability, 100 different realizations are created with a commercial geostatistical simulator. This paper evaluates the averaging approach in terms of the mean error and the distribution of errors for each value of the standard deviation.
The error shows significant dependence on averaging methods especially for the reservoirs with high heterogeneity. Geometric based averaging shows the smallest error from the viewpoint of the mean error for high heterogeneity. Also, its distribution of the errors is narrowest, which indicates that the geometric based averaging method demonstrates the most stable performance. In contrast, the harmonic based averaging method represents the biggest error in terms of the mean value and has the least stable error from the viewpoint of its distribution.
The work establishes an approach to consider the matrix heterogeneity in unconventional reservoirs with FMM. Through the integrated case studies, the most appropriate method for the different heterogeneities is evaluated. This study makes a significant contribution on the development of Fast Marching based reservoir characterization for more robust application for unconventional reservoirs.
Field Results of a Real Time Drilling Fluid Monitoring System
Authors: Magalhães Sérgio , Calçada Luís Américo , Scheid Cláudia , Paraíso Eduardo , Moraes Gabrielle , Valim Elias , Almeida Heraldo , Waldmann Alex , Leibsohn André , Marques de Sá Carlos Henrique 
Published: July 2020

Abstract
An automated system was developed to determine some physical properties of the drilling fluid in real time during drilling operations. Rheology, density, electrical stability, total solids suspended and water in oil ratio were determined in real time during onshore drilling operation. This work presented the results obtained using the system, comparing it with data obtained by standard offline methods according to API. The first stage of the development was performed in laboratory where the monitoring container was connected to a fluid flow loop was built. Rheology was determined using an inline modified concentric cylinder viscometer. The device was capable of determining shear stress at different shear rates. Density was determined by a Coriolis device, electrical stability was calculated by a self-designed device built under API technical design, water in oil ratio was provided by electromagnetic means of a commercial device and total solids suspended was calculated using a developed material balance equation, which uses real time data of density and water in oil ratio as inputs. The entire system was assembled into a skid, fully automated and controlled by in house developed software, adequate to be transported and installed at rig sites. The second stage was to test the system in onshore rig sites in northeast of Brazil. With automatic control of flow rate and pressure, the system performed measurements in the rig site drilling fluid, pumping the fluid in and out of the system, operating as a bypass of the main pressurized drilling fluid flow line. The system reported data locally on a screen and transmitted to a remote operations center. Density, electrical conductivity, total solids suspended and water in oil ratio were provided at every second. Viscosity profile was provided every 30 min with calculation at 6 different shear rates, in accordance to API. Electrical stability tests were performed every 30 min with 1 min of duration. The developed system performed measurements properly in the onshore rig sites. All technical requirements for operational safety were met, as well as environmental and electrical hazard managed. Overall statistical deviations calculated between online and offline reference data reported were considered satisfactory. The system constitutes the most complete project for real time fluid monitoring properties in real time. Several fluid properties (electrical stability, water oil ratios) were measured online for the first time. These properties are a requirement for real time diagnosis software and an essential input for autonomous drilling projects.
Improving CSS Performance with Preformed Foam: Teca - Cocorna Field Case
Authors: Perez Romel , Rodriguez Hector , Barbosa Carolina , Manrique Eduardo , Garcia Luis , Rendon Gabriel 
Published: July 2020

Abstract
Cyclic Steam Stimulation (CSS), is the most applied thermal enhanced oil recovery (EOR) method worldwide. However, despite the vast experience gained over the last few decades CSS still has its challenges including but not limited to energy efficiency and operational costs. CSS has been evaluated for several years in Colombian heavy oil reservoirs. As CCS approaches its maturity, new alternatives and injection strategies are required to potentially extend the technical-economic limit of this recovery process.
This work is focused on the procedure implemented during the design, execution and monitoring of the hybrid technology of steam plus foam as a strategy to improve the performance of a mature CSS process. The strategy developed for experimental tests, numerical simulations and pilot test is described. The evaluation of well head configuration, injection facilities and schedules to assure a good quality and stability of the preformed foam is also discussed.
The CSS-foam injection pilot was performed in Teca - Cocorna field. The cumulative surfactant injection was between 3 to 5 tons distributed between two mature wells under CSS at a concentration of approximately 2500 ppm. The facilities used for the foam generation with nitrogen at surface conditions and well injectivity performance will be discussed.
Early incremental production due to foam injection has been positive. The first CSS-foam pilot tests allowed the assimilation of lessons learned to incorporate best practices for the continuous improvement in the operation of CSS processes. The performance of CSS-Foam will be updated based on the pilot results due to the level of uncertainties associated with the scaling of laboratory results. According to the performance of the pilot, Ecopetrol will continue evaluating this hybrid CSS technology to improve oil recovery and energy efficiency in fields with steam injection.
Downhole Steam Quality and Flow Rate Estimation in Selective Steam Well Injection Completions
Authors: Rodriguez-Prada Hector A , Delgado-Delgado Patricia 
Published: July 2020

Abstract
Objectives/Scope: To determine quality, mass and volumetric flows in each sands where steam has been injected using well completions with selectivity elements under critical regime. From pressuretemperature logs and ILT run in wells, were used to estimate density, volumetric and mass flow of steam, and heat injected at each distributor element which wells are completed.
Methods, Procedures, Process: When steam is injected into a well, the quality and mass flow at the well head is usually known. With the logs of pressure and temperature, together with the ILT and flow control devices in critical regime, it is possible to know the conditions of the steam (saturated, sub-saturated and over-saturated), and speed of flow, it is possible to determine in function of the completion of the well, diameter of tubing for injection and diameter of the throat, the following variables or properties, like volumetric flow, mass flow, quality and density of the steam, in each point or element for distribution of the well.
Results, Observations, Conclusions: The methodology developed has allowed to determine the steam mass flow and injected energy that flows in each distributing element and how much is injected in each selected sand, obtaining that the highest mass flows are obtained where the lower qualities of the steam exist and vice versa, as well as the total energy injected in each sand looks almost independent of the steam quality in a range of 15% to 90%. This is due to the behavior of the mass flow and the latent heat of vaporization and their relation to the quality of the steam in throat under critical regime. As the steam quality increases, the mass flow through the throat decreases, and by the contrary the latent heat of vaporization increases. So the combination of both generates a total heat injection is almost independent of the quality of the steam, and the total amount of heat injected being a direct function of the diameter of the throat and the number of devices used for steam distribution.
Novel/Additive Information: The novel combination of flow equations in pipes, critical flow in throat and flow through the spinner used in the ILT, allowed to estimate the mass flow and the energy injected into the reservoir with wells using selective completions in critical flow conditions. It was determined the existing differences in the conditions used during the design of the well completion and those existing during the steam injection. With this new methodology, the steam injector well completion is optimally designed, as well as obtaining the efficiency of the steam injection by sand, through a better estimation of the SOR and the oil incremental recovery during the continuous steam injection process.
A Systematic Volcanic Intrusive Characterization Model for Exploration and Production of Vaca Muerta Formation
Authors: Utge Silvana , D’Angiola Marta , Dominguez Fabián , García Daniel , Ruiz Ronyl , Rodríguez Jesús , Pérez Gustavo 
Published: July 2020

Abstract
This paper presents a new approach based on a systematic workflow that diminish the uncertainties regarding heterogeneities and other geological factors that dramatically impact the unconventional reservoir performance in Vaca Muerta. In addition to the natural heterogeneities caused by marine depositional sub-environments that formed rock configuration variability, both vertically and horizontally, some areas of Vaca Muerta are affected by subsequent volcanic activity that creates complex characteristics for drilling and completions.
A detailed geological, mineralogical and petrophysical characterization from the pilot well is performed to precisely determine landing points as well as the identification of traversed volcanic intrusive bodies. Pilot hole characterization added comprehensive knowledge to the horizontal drilling operations using Geosteering by decreasing geological uncertainty and allowing full control of drilling through the LWD azimuthal information in real time, and therefore making decisions to obtain optimal well placement. Critical information about elemental gamma ray spectroscopy (U / Th/ K, e.g.), that revealed specific reservoir characteristics of the depositional environment, supported the hypothesis of the heterogeneity of Vaca Muerta Formation and helped to identify the intrusive bodies.
The workflow is completed with a complete structural evaluation, identification of natural fractures and textures from electrical borehole images logged in Oil-based mud environment. This analysis defined precisely the intrusive (dikes and sills) configurations. Textural and mineralogical characteristics, as well as information about their location, spatial and relative geometric development are included in the evaluation. The analysis provided critical inputs for completion decisions as well. Operational and evaluation results are used as the platform for future developments of new exploratory non-conventional areas.
Building A Production Analysis Tool for Analog Field Analysis Brazil and Mexico
Authors: Pederson John M. , Eburi Simeon , Boyarko Devin C. 
Published: July 2020

Abstract
This paper showcases how public data was integrated using data visualization software to develop appropriate analog information for new prospects and field evaluations in Brazilian Campos and Santos and Mexican Gulf of Mexico deepwater plays. The data visualization software was selected for its ability to integrate geologic map files (.shp files) and digital production data. This work was extended to evaluate Mexican opportunities since similar production data is available from the government.
In the exploration workflow, analog field data is used to develop potential prospect estimated ultimate recovery ("EUR"), recovery factors, the appropriate EUR per well and initial production rates. This information is then used in a conceptual development plan that allows potential economic scenarios to be assessed. Both in Brazil and Mexico, substantial well data is available from the respective governments. The team successfully used this information to develop appropriate low, mid, and high oil production forecasts.
Machine Learning Models To Automatically Validate Petroleum Production Tests
Authors: Machado de Almeida Duque Maria Clara , Souza Chaves Gabriela , de Oliveira Monteiro Danielle , Velasco Medani Luciana , Martins Ferreira Filho Virgílio José 
Published: July 2020

Abstract
Well production in oil fields is a dynamic and complex activity. The patterns and characteristics inherent to the well, such as pressures and flow rates, are changing based on production time and the fluid composition – a complex multiphase mixture composed of oil, water, and gas. Thus, it is necessary to evaluate well behavior with periodic production tests. This paper proposes an automatic tool based on machine learning models to assist the production tests validation process in a quick manner. The developed methodology was applied to 13 representative wells of a Brazilian offshore oil field. For each examined well, a dataset is created with operation variables obtained from valid and invalid production tests. Six classification algorithms are analyzed, Logistic Regression, Naïve Bayes classifier, K-Nearest Neighbor, Decision Tree, Random Forest and Support Vector Machine (SVM) in reason to automatically label a new production test as valid or invalid, according to production historical data for the well. The dataset was divided into training and validation sets. The training set was used to perform feature selection, to calibrate and choose the proper model. The validation set was then used at the end of the procedure to evaluate obtained results, by comparing the model’s output with real test labels. From the results obtained in the case study, it was possible to identify that IGLR (Injection Gas/Liquid Ratio), oil flow rate and the pressure loss between wellhead and platform were representatives for most of the wells, which implies that these variables have a huge influence at the production well test validation. Furthermore, the validation set indicates that SVM and logistic regression were the models with the best performance. Besides that, accurate results were achieved, since the model correctly classified at least 5 of the 6 tests in 70% of wells analyzed, and for the remaining wells, 4 of 6 production tests.