bluuebunny/crossref_metadata_2025_split huggingface dataset:
Robust Artificial Lift Solution for Ultra-Deepwater Heavy Oil Atlanta Field
Authors: Cavalcante Barbara Ferreira , Rocha Paulo Sergio , Santos Marcelo Paulino , Tavares Alexandre , Neto Salvador Jose Alves , Matos Joao Siqueira , Marsili Marcelo Danemberg 
Published: October 2019

Abstract
Most of the artificial lift strategies in deepwater environments require sophisticated and robust solutions, aiming to improve the system's run life and reliability. Due to that, oil companies choose only trustable technology and field-proven solutions for artificial lift design. This is the case of Atlanta Field's artificial lift project, with electrical submersible pumps (ESP) installed at more than 1,550 m water depth, to produce heavy oil.
For Atlanta Field, the ESP must handle high viscous oil and emulsions at high flow rates to be economically feasible. To achieve this goal, it was deployed one of the most powerful ESP in the world with 1,550 HP induction motor and more than one hundred pump stages into the well. This is the largest ESP in-well successfully installed in Brazil.
The artificial lift strategy adopted for Atlanta Field was an in-well ESP as primary method and an artificial lift skid (ALS) installed on the seabed for back-up. When the primary method fails, there is no in-well ESP replacement, because of high costs involved with workover and the back-up system becomes the main one. When the back-up system fails, the replacement of the pumping module is done by an AHTS equipped with active compensate crane for subsea installation. In this way, replacement costs are much lower than those needed to replace pumps inside the wells.
So far, this artificial lift strategy has proven to be reliable and project results will be discussed in this paper. Strategies to optimize production will be addressed and observations regarding free gas ESP pumping will be made.
After a period producing, the in-well ESP have failed, and the ALS became the main system to produce both wells, as planned. The project faced some challenges with ALS operation, since there was an expressive flow restriction in the in-well ESP. Experimental tests were permeformed to better determine the pressure drop caused by the flow through the pump stages and to propose a solution to the production restriction. By-pass valves were adopted in the project to avoid the mentioned issue.
The well ATL-4 was drilled in March 2019. As this operation requires a drill ship, it was decided to perform workovers in wells ATL-2 and ATL-3 to replace the in-well ESPs and install the by-pass valves in the well's production string.
New Strategies for Cost Reduction with Depth Correlation in Deepwater Wells
Authors: Pereira Yerecê Da Silva , Scudino Borges Raphael Pereira , Schnitzler Eduardo , Roman Roger Savoldi , Paraski Henrique Von , Destri Alice Claussen , Destri João Almeida , Gozzi Danilo Signorini , Baumann Carlos , Merino Carlos 
Published: October 2019

Abstract
Some completion operation steps, such as perforation and packer seating, require that the degree of uncertainty be limited. The main correlation methods used today are based on tally accuracy, tagging a known element in the well or using wireline gamma ray readings. This paper discusses the development of four alternative depth correlation techniques that aim at avoiding the use of wireline in completion and well testing scenarios. All these methods were implemented in field jobs and demonstrated their efficiency with lower operational cost, higher operational safety and acceptable margin of error for the target job. Two methods are based on gamma ray readings and to send data to surface they use logging while drilling (LWD) and wireless telemetry. Target applications for these two methods are tubing-conveyed perforation (TCP) and well testing operations. The other two methods use casing internal diameter (ID) changes at known depths to determine string depth. One uses a rigid hole-opener to tag a crossover or the top of a liner and the other uses the pressure drop produced by a packer entering into a well section with smaller ID. The main advantages of these new depth correlation techniques are rig time savings and greater operational safety by reducing personnel exposure to dangerous operations.
Dissolution Behavior of Carbonate Rocks from Brazilian Pre-Salt at Reservoir Conditions by LSWI
Authors: Borges Tálisson Carvalho , Vidal Vargas Janeth Alina , Koroishi Erika Tomie , Kim Nilo Ricardo , Trevisan Osvair Vidal , Bassani Gabriel Soares 
Published: October 2019

Abstract
The low salinity water injection (LSWI) is one of the most studied techniques applied to enhanced oil recovery (EOR) from carbonates reservoirs. Wettability alteration and dissolution reaction are mechanisms that support the understanding of this technique. However, the dissolution behavior of Brazilian pre-salt carbonates rocks when treated by LSWI is not yet known. Therefore, the purpose of this work is to evaluate the dissolution effects provided by low salinity water injection in carbonate rocks from a Brazilian pre-salt reservoir using two different injection flow rates in core flooding tests at reservoir conditions. Porosity variation along the length was determined by Computerized Tomography scan analysis. Permeability was determined through pressure drop data. Ions identification and concentration were determined by ions chromatography. The experiments consisted in carrying out two core flooding tests assembled in series at 8100 psi of injection pressure and 65°C. It was performed two different injection flow rates (1 mL/min and 0.1 mL/min) of 16 times diluted synthetic seawater. It was possible to observe three different porosity behaviors along the sample length in both flow rates tested and for both core holder samples. However, the porosity behavior intensity is different from each case. There are regions of predictable behavior, regions of random behavior and inert regions. According to the porosity plots, the sample from the second core holder of the series presented more interaction with the injection fluid. Probably, the mineralogical heterogeneity has influenced in the dissolution phenomenon. The permeability profile remained almost constant for both samples. The ion chromatography analysis revealed a huge variation of magnesium and calcium ions concentration in the first injected porous volume and, subsequently, a constant trend towards the base-line values.
Forecasting Smart Well Production via Deep Learning and Data Driven Optimization
Authors: Calvette Taisa , Gurwicz Allan , Abreu Ana Carolina , Cavalcanti Pacheco Marco Aurélio 
Published: October 2019

Abstract
As smart well technology is increasingly being adopted in oilfield development projects, the need to optimize controls emerged in order to justify its higher initial investment by considerably increasing net present value. While there are numerous methodologies to achieve this goal, a common fact in all is the need for a great number of computationally expensive reservoir simulations, hindering extensive optimizations. This paper proposes the use of deep learning algorithms in proxy models, in order to accurately replicate the behavior of the simulator by forecasting production based on previous data. Thus, a smaller number of simulations are required for a training dataset, and the proxy can then be used in lieu of the simulator for optimization purposes. Other benefits in the use of the proposed methodology include the gathering of insights on production, as problems might be occurring if measured production noticeably deviates from the forecast. Two case studies were done, and the results indicate that a Long Short-Term Memory Network-based proxy is able to forecast production with a remarkably low error, validating the methodology and supporting its use.
On the Ultimate Limit State Strength Models and Its Application for Casing Design
Authors: Nogueira Araújo João Paulo , Pereira Gouveia Lucas , Toledo Lima Junior Eduardo , Barbosa Silva Thiago , Lopes Rodrigues Anjos Jorel , Lima Oliveira Felipe , Matos Lira William Wagner , Lima Santos João Paulo 
Published: October 2019

Abstract
It is proposed a new methodology for calculating safety factors in triaxial casing design, regarding Ultimate Limit State (ULS) models. The definition of an equivalent axial force allows an unified graphical approach, in which both ULS and Serviceability Limit State (SLS) envelopes are represented in the same space. A review of the ULS casing design proposed in the API TR 5C3 (2008) standard is presented, and some considerations are made on the usage of Klever-Stewart and Kever-Tamano models. Both are defined for combined load analysis but are not effective for triaxial casing design routine, for they only compare the applied internal/external pressures to the design limit. Thus, two additional limit states are verified: axial and triaxial. Furthermore, the ULS envelopes (Klever-Stewart and Klever-Tamano) are plotted in the same load space as the SLS envelopes, allowing for an analysis on both limit states in a single graphic. During studies of the Klever-Stewart and Klever-Tamano formulations it was verified that, despite both being combined models (the external/internal pressure and axial load influence the internal/external pressure resistance), the consideration of their uniaxial safety factors might not be enough to ensure if the tubular is about to fail. There are some special load cases where other failures might occur prior to burst/collapse. The ULS envelopes are revisited, using the very same equations proposed by the API TR 5C3 (2008), but in a different load space, which also allows the representation of SLS envelopes, providing a complete evaluation of the tubular strength against the load scenario. The studies also revealed some drawbacks inherent to the Klever-Stewart and Klever-Tamano models, as the existence of inadmissible pressure resistance beyond the axial ultimate tensile strength. The new paradigm of ULS is challenging and it is not well established in terms of design practice. In the light of this, it is presented a new methodology for computing safety factors in ULS analysis, effectively comparing them to the SLS approach, in order to support the decision-making process in casing design and the well integrity verification.
Optimization Methodology of Artificial Lift Rates for Brazilian Offshore Field
Authors: Bezerra Matheus De Freitas , Vigano Guilherme Cosme , Giuriatto Jean Luis 
Published: October 2019

Abstract
Nowadays gas-lift is still a very expressive artificial lift method, for instance considering the whole Brazilian oil production profiles, gas lifted wells are responsible for 30% of monthly production. Due this huge importance, the injection efficiency should be ensured to avoid lid gas losses and maximize the production. Then, this study had as objective to develop a Gas Lift Optimization workflow and define the optimum lift rates to increase the reservoir recovery and improve gas usability due to platform constraints of a Brazilian deep-water field. That workflow comprises a reservoir and flow assurance simulators, achieving more accurate responses compared to regular workflows. Taking advantages of the proposed method, multidisciplinary teams could work together which increases the representativeness of such studies providing important outcomes for decision makers. At this study, due to a gas-lift optimization was observed an increase of 0.5% at cumulative production with a huge gas-lift reduction of around 40%, resulting in a better financial balance of the project, saving a considerable amount of lift-gas. The methodology adopted to optimize the injected gas lift rate and consequently increase/maintain cumulative oil production proved adequate for application in oil fields that are highly dependent on artificial lift methods. Therefore, exploration and production projects can be financial healthier.
Detailed CFD Simulations of Green Water Flow on FPSO Deck
Authors: Silva Daniel Fonseca de Carvalho e 
Published: October 2019

Abstract
Oil production in ultra-deep waters places some new challenges for floating units. As an FPSO is one of most common types of production units adopted by Petrobras, its behavior in extreme conditions has to be fully tested and verified. During extreme sea storms, ship type floating structures may be subjected to water on deck events (green water). In order to allow a detailed structural analysis, Computational Fluid Dynamics (CFD) techniques may be used to investigate detailed loads due to water on deck propagation, especially in beam sea conditions, which are not traditionally covered by maritime rules.
Based on model test results, water ingress and water on deck propagation are simulated through CFD analysis. The methodology adopted consists of two different approaches: (i) The influence of a riser balcony lateral extent is analyzed based on a 2D wave propagation model and; (ii) the complex flow behavior through topside equipment is discussed by using a 3D simulation of a restricted deck area, including some strategies for impact protection.
The results of the simulations allow investigation of the complex flow behavior depending on the riser balcony extent and topside configuration, as well as the resulting loads on critical structures. For a side hull balcony, its protective effect against wave run-up in beam waves is only effective with a lateral extent of 8m. By performing water on deck simulations, the benefits of "V" type protections are quantified leading to 20% loading reduction when compared to flat plates.
The simulations reveal CFD as a very powerful tool to assess detailed transient pressure distributions for optimized structural design.
P-67: Review of Dry Transportation of FLNG’s/FSRU’s/FPSO’s
Authors: Lira André de , Pinheiro Marcio , Leuwen John Van , Seij Michel , Goetheer Ronald 
Published: October 2019

Abstract
Boskalis Offshore executed the dry transportation of the P-67 FPSO in 2018 from Qingdao China to Rio de Janeiro in Brazil. One of the main challenges for this project is the sheer size and weight of the P-67 FPSO. In order to transport the P-67 FPSO in a safe and controlled manner, new loading concepts and support structures have been developed.
This paper addresses the challenges and lessons learned of the P67 FPSO transportation project. By means of several tangible examples and comparison with wet-tow the reader is explained how the dry-tow method benefits the transport of the P67 FPSO. The P67 FPSO is a critical asset for gas production, and as a result benefits deepwater FLNG in general.
High level these benefits can be found in: Design optimizations - Stationary structures can be designed lighter and equipment can be optimized for local environment.Schedule optimizations - Dry transport increases schedule reliability and reduces time to market.Risk reduction - Reduced duration of exposure to risks at sea and specifically in critical areas.
Hybrid Composite Flexible Risers in Free Hanging Catenary Configuration and Flowlines for UDW Projects
Authors: Loureiro Jr. Walter Carrara , Sobreira Rafael Guimarães de Mello , Buckley Adriana Loureiro da Silva 
Published: October 2019

Abstract
Large diameter UDW flexible pipes usually require lazy-wave configuration to withstand operational fatigue life. In a response to the current uncertain oil/gas price, the opportunity to design and deploy Free Hanging Catenary risers has been identified as the means to significantly lower CAPEX of flexible risers installed while securing the required life-cycle performance, including optimized offshore installation, 30-year fatigue duties.
The most promising concepts to deliver free hanging configuration are based on composite flexible pipe designs, but these solutions rely on new technology (or at least new application of technology) and will need to undergo all new technology development phases including "Field Qualification" stage before they are ready to be considered as a base case for any UDW Project.
Composite flexible pipe considers the adoption of new composite materials layers replacing one or multiple layers of a conventional flexible pipe for at least one pipe section. Several new hybrid pipe concepts can be developed considering this approach. Considering current Industry Standards and Brazil Regulations many challenges can be identified to deploy this type of new technology. These pipe concepts do not fit in the definition of existing Standards. In addition, the unknown behavior of these material and layers in a flexible pipe will increase the integrity assessment complexity.
During the development phase the integrity assessment challenges and potential gaps in industry standards will have to be addressed as well to avoid misalignment or conflicts with regulatory requirements.
Electrocoagulation Treatment for Reverse Electrodialysis Wastewater from Petroleum Refinery
Authors: Gonçalves Filipe Mattos , Galdino Duarte Tocafundo Dhayannie Hellen , Alvarenga Santos André Luiz , Nigri Elbert Muller , Ferreira Rocha Sônia Denise 
Published: October 2019

AbstractThe present study investigated an evaluation efficiency of electrocoagulation (EC) for the pretreatment of a saline concentrated effluent from the reverse electrodialysis (RED-C) stage from an oil refinery, aiming at water reuse in the industrial process. In this approach, an electrocoagulation system with 1 L capacity was set up for batch treatment using aluminum electrodes. Initially, experiments with a semi-synthetic RED-C effluent were assessed for contaminants removal using fixed current density of 8.30 mA/cm2 and 1 cm distance between electrodes. The influence of initial pH (5 and 7), controlled temperature (20, 30 and 40°C) and operation time (60 and 120 min) on removal efficiency was investigated and solid residue were measured. The results showed that the optimum conditions were at pH 7 and 20-30°C with removal rates around 70%, 57%, 10% and 44% for Ca, Sr, Na and COD, respectively. Thereafter, experiments were conducted with a real RED-C using the best condition founded in preliminary tests, this time applying a current density of 5 and 10 mA/cm2 and 0.5 cm distance at room temperature (approximately 23°C). Regarding the tests with real RED-C, for both current densities the removals were greater due to decrease in distance between electrodes and larger temperature range that improved electrocoagulation. In general, the use of current density of 10 mA/cm2 and reduction of inter-electrode distance increased EC efficiency which exhibited removal rates of 88%, 77%, 26% and 24% for Ca, Sr, Na and COD, respectively. Although, it was observed a decrease in COD removal from real RED-C due to the addition of inorganic ions in the semisynthetic effluent that precipitated as salts, removing more organic as a coadjuvant compound. The solid slugde production for this same condition were 5.65 g/L.
Estimation of Three-phase Oil Relative Permeability in WAG Experiments
Authors: Aghabozorgi Shokoufeh , Sohrabi Mehran , Facanha Juliana 
Published: October 2019

Abstract
Simulation of many enhanced oil recovery (EOR) methods such as water alternative gas (WAG) requires accurate determination of relative permeability (kr) data under different saturation histories. Relative permeability is a function of several factors such as wettability, spreading coefficient and fluid pore occupancy. Experimental measurements of three phase kr data are time consuming and difficult considering infinite possible flow paths in the three-phase flow regime. There are several models in the literature to estimate the oil relative permeability data in three phase systems (3P-Kr models). However, the available models can not accurately estimate the oil production in low oil saturation region observed in WAG experiments.
In this paper, Stone I model has been modified to improve the estimation of oil kr data. To this aim, the behaviors of three phase flow in immiscible and near miscible WAG experiments were considered. It was shown that the Stone model overestimates the oil relative permeability data in the low oil saturation regions. In addition, it was revealed that Stone's exponent model cannot simulate the gradual decreace in the oil kr data. To improve the results, a new coefficient is incorporated into the model to consider the impacts of the disconnected oil clusters during the cyclic injection. In addition, the end-of-cycle residual oil saturation (Som), which was required based on the Stone model, is no longer needed in this modified model.
Compact Hydrate Dissociation Plant: Combined Direct and Indirect Heating for Increased Efficiency
Authors: Margotto Romulo Mantovani Augusto , Franklin Gabriel , Cunha Jeferson 
Published: October 2019

Abstract
Hydrate formation in production and control lines has been a serious issue in the oil industry, especially in the deepwater offshore market. This article focuses on a compact temporary plant designed to be assembled on offshore rigs for heating and injecting high flow rate water to break hydrates.
Hydrates are formed under determined conditions (high pressure at low temperature) in which natural gas hydrocarbon molecules are trapped in ice molecules, forming crystal structures and plugging or choking lines, causing operational problems. When preventive solutions, such as chemical inhibitors or thermal insulation, do not work, the formed hydrate must be broken or dissociated to set the lines free. One option is active heating, in which hot fluid is circulated to increase the temperature and break the hydrate ice structures. Consequently, a compact plant, with combined direct and indirect heating, was designed to deliver a customized solution for an offshore rig.
Drill or salt water pumps were used to supply cold water at 12 bpm at 25 °C, and two steam generators were used to inject steam into the flow, mixing inline and delivering water at 49 °C at the mud tanks. This tank water was pumped through mud pumps at 12 bpm, passing through four steam heat exchangers (SHE) to deliver water at a final temperature of 90 °C. The total process used six steam generators and four SHE to heat water from 25 to 90 °C at 12 bpm.
The compact design for the high flow rate injection plant was only possible with combined and independent processes. Direct heating by steam injection was used inline downstream from the drill water pump to preheat the water to 49 °C while feeding the mud tank. Indirect heating used four SHE downstream of the mud pump to deliver water at 90 °C at the seabed.