bluuebunny/crossref_metadata_2025 huggingface dataset:
An Innovative Partnership to Develop an Oman Based Pressure Pumping Company
Authors: Hogan M. R. , Willis R. B.
Published: September 2016

In 2011, a subsidiary of the Oman Oil Company embarked on an effort to develop an Oman-based pressure pumping capability. What developed was an innovative partnership between a US-based service company and the Omani company. Technology transfer and training for Omani management and personnel was carried out in a hands-on and interactive fashion in the United States.

Throughout the process, the goal was to utilize Omani personnel as fully as possible. A well-defined list of equipment, technologies, and required materials were procured along with the training of key personnel. The plan had to be efficient in training and transferring the necessary skill sets to all phases of the human complement necessary to design, operate and maintain the highly technical equipment required in today's pressure pumping industry. HSE concerns were a cornerstone of every facet of the project. The paper will walk through the project and demonstrate the cooperation and structure that resulted in a successful business introduction to the Sultanate of Oman.

The final result was a successful launch of a fully functioning Omani-owned pressure pumping company in the Sultanate of Oman during the summer of 2013. This paper will outline the many varied disciplines, technologies, and hurdles that were worked through during the process. The planning required the development of a variety of interrelated schedules so that the equipment design, procurement, and delivery schedule meshed with the necessary personnel development needs.

With the expanding need for unconventional resource development, many countries are excited about the prospect of developing their own indigenous pressure pumping capabilities. The paper describes in detail how proper in-depth scoping and planning can result in a viable and successful indigenous new business start-up where none had previously existed.
Current State and Future Trends in the Use of Downhole Fluid Analysis for Improved Reservoir Evaluation
Authors: Elshahawi H. , Dong C. L. , Ramaswami S. R. , Cornelisse P. W.
Published: September 2016

The introduction of downhole fluid analysis (DFA) two decades ago was a major addition to the wireline formation testing suite of measurements previously available in the industry, both in to optimize the sampling operations real-time and to provide additional fluid measurements as an integral component of integrated fluid property interpretations. The progression from basic measurements such as fluid resistivity to advanced optical analysis has paved the way for much improved definition of reservoir fluids, including the variation of fluids within reservoirs.

Downhole Fluid Analysis is a continuously evolving field, so we will begin this paper by looking back at the history and evolution of various types of sensors for operational real-time decision making as well as post-operational fluid evaluation. Our emphasis will be to catalogue the strengths and limitations of each method and highlight the importance of integration. We will then highlight current capability gaps, focusing on the need for improved real-time contamination monitoring in some environments of interest and our desire to measure additional fluid properties and specific species concentrations.
Oil Industry First Interwell Trial of Reservoir Nanoagent Tracers
Authors: Kosynkin Dmitry , Alaskar Mohammed
Published: September 2016

This manuscript reports the industry's first proven reservoir nanoagents' design and describes a successful multi-well field trial using these inexpensive and environmentally friendly nanoparticles that offer an important advantage of fast and cheap fluorometric detection. Our fundamental nanoparticle tracer template, A-Dots or Arab-D dots, is intentionally geared towards the harsh but prolific Arab-D carbonate reservoir environment of 100°C temperature, 150,000 ppm salinity, and an abundant presence of divalent ions in the connate water. The A-Dots were manufactured on a scale of one metric ton from affordable and easily available commodity chemicals. They were injected into a watered-out part of the field and monitored at four nearby producer wells for two years. Monitoring of four neighbouring producer wells over a period of 26 months confirmed nanoparticles' breakthrough at a single producer nearly 500 m from the injector at the reservoir level, thus, proving the nanoparticles' mobility and transport capability. The maximum concentration of the nanoagent in produced water was observed about 10 months after the injection matching the behavior of conventional small-molecule tracers used in the same pair of wells previously. The rate of A-Dots production correlated with the rate of water injection at the original injector well and followed it closely with a 10-month delay.

This test bolstered our previous observations of satisfactory recovery of A-Dots in a single-well test by confirming their reservoir stability on industry relevant time scales and demonstrating the feasibility of their industrial production. The importance of this accomplishment is not in how sophisticated the sensing functionality of the tracer design is but rather in the nanoparticle stability, mobility, scalability, and field application potentials. Our findings render the concept of having active, reactive, and even communicative, in-situ reservoir nanoagents for underground sensing and intervention a well anticipated near-future reality.
Successful Identification of Cold Oil Steamflood Development Projects
Authors: Popa Andrei , Woolford Jeff , Cassidy Steve
Published: September 2016

Although the hottest topic today is unlocking unconventional resources, the established heavy oil reservoirs continue to offer a great opportunity for growth given the relative low cost of development. The mature heavy oil reservoirs generate high returns given the existing infrastructure in terms of facilities, pipeline, generators, knowledge of the steam distribution, and the continuing technology advancements in subsurface understanding and modeling

In this study we introduce a novel approach for the successful identification of remaining cold oil steamflood opportunities in a mature field through the use of heat management knowledge, large data utilization, ArcGIS and mapping artificial intelligence technologies. The methodology exploits the log data and existing full-field earth model and automates the screening and ranking of development patterns of a large heavy oil field. The workflow proposed replaces the manual engineering approach which uses hard cut-offs applied on key petro-physical properties to find promising areas for development.

The combination of the knowledge acquired during 30 plus years of operations, integrated with intelligent data driven technologies generate tremendous business value to smart operators who pursue these opportunities and continue to embrace these types of resources.
Analytical Study of Flowing and In-Situ Compositions in Unconventional Liquid-Rich Gas Plays
Authors: Zhang Miao , Ayala Luis F.
Published: September 2016

Liquid-rich gases in unconventional reservoir environments can exhibit complex phase and flow behavior due to gas condensation and re-vaporization and differences in phase mobilities that results in compositional variations inside the system. To date, the analysis of in situ and flowing composition variation in unconventional liquid-rich wells has been largely limited to numerical modeling. This work uses an analytical approach to study the in situ and flowing fluid composition of gas condensate wells producing under infinite-acting linear flow—a commonly observed flow regime in hydraulically-fractured horizontal wells in unconventional formations. We propose a semi-analytical solution to the governing partial differential equations (PDEs) written in terms a compositional fluid formulation. The proposed solution is developed using Boltzmann's transformation and is validated by both analytical development and numerical simulation data. Results corroborate that when hydraulically-fractured horizontal wells are producing against a constant bottomhole pressure (BHP) constraint, the producing wellbore fluid composition remains constant as long as the system remains infinite acting, leading to a constant producing gas-oil ratio (GOR). This constant wellstream composition is shown to be very different from in situ composition, which varies according to pressure and production condition inside the reservoir.
Development of a Reactive Transport Simulator for Carbonates Acid Stimulation
Authors: Maheshwari P. , Gharbi O. , Thirion A. , Ali N. S. , Peyrony V. , Aubry E. , Poitrenaud H. M. , Benquet J. C.
Published: September 2016

An accurate description of reactive transport phenomenon in porous media has major applications for many processes such as, contamination in groundwater resources, carbon capture and storage, enhanced oil recovery, and acid stimulation. These processes, involve surface reaction coupled with flow that result in dynamic alteration of the porous media structure. More particularly, in well acidizing, an accurate understanding and control of the stimulation operations outcomes still represents a major challenge in heterogeneous carbonates. The objective of this paper is to describe how an integrated experimental and numerical approach is adopted to develop a core-scale reactive transport simulator that could be used to investigate acidizing efficiency in carbonates.

A series of core flooding experiments were performed on Richemont carbonate blocks from queries at reservoir temperature. A back pressure valve system is used to eliminate the effect of free gaseous CO2 on the flow dynamics of acid. Moreover, mathematically, a continuum-scale model was used to describe the reactive transport phenomenon. This model consists of fluid transport, continuity, species balance, and porosity evolution equations at a continuum scale. The porous media characteristics such as permeability and pore radius are obtained as a function of local porosity using closure relations. The rock properties required as input to the model come from numerous experimental techniques such as computed tomography (CT), Mercury injection capillary pressure (MICP), and X-ray diffraction (XRD)

The numerical results obtained using the model, show a close match with the experimental observations, in terms of pore volume to breakthrough (PVBT). Additionally, the developed model was able to reproduce the different dissolution regimes along with the transient pressure response, as observed experimentally.
The Role of E-Well Books in Conducting Integrated Well Reviews and Identification of Production Optimization Opportunities, A Case Study from Iraq
Authors: AlSaad Radhwan , Subramanian Sundararaman , Al Jumah Ali , Kumar Randhir , Alharthy Said
Published: September 2016

Data integration helps in arriving at informed decisions and to manage assets efficiently. During the entire lifecycle of operations, starting from drilling to production operations, various disciplines that cover Subsurface (Geology, Reservoir Engineering and Geophysics), Well Engineering, Production Technology, and Asset Maintenance are involved. Each of these domains generates its own specialized sets of data which are maintained in various databases and applications. These disciplines wise fragmented data items can be linked under a hierarchy with either a Well/Reservoir at the top level. Managing key information across the entire lifecycle of a Well/Reservoir then requires combining data from diverse sources and bringing them in one unified view. Electronic Well Book is a key solution that translates this requirement, of having one view from diverse data elements covering various disciplines. Like a physical book, the Electronic Well Book is designed with each well as a chapter and the data elements that capture key events, data gathered, data analyzed and live data are represented as individual pages. The Electronic Well book is a tool that provides one source of data, faster data access, better defined quality checks, and integrates work flows, making collaboration easier. The well book method of information representation ultimately contributes significantly in identifying production enhancement opportunities, which when matured and executed leads to production gains. In addition, the live feed data facilitates monitoring rates/pressures and identifying deviations from the trends, reporting them accordingly in the same chapter, upon which actions to be taken.

E-wellbooks fulfill the objective of having only one source of truth, one integrated database, where every team member will find any piece of information with minimum effort, shorter period of time and more efficient manner. The case study presented herewith, demonstrates the pragmatic approach followed in well reviews and the value generated utilizing this novel methodology.
Ultra-high Temperature Rated Elastic Carbon Composite Packer for Reliable Downhole Zone Isolation
Authors: Xu Zhiyue , Zhao Lei , Prieto Carlos A.
Published: September 2016

This paper presents the oil industry’s first ultra-high temperature elastic seal element that is made from a novel elastic carbon composite (ECC). The discussion centers on the ECC composite design, superior material properties compared to elastomeric seal materials, and the reliable performance of an ECC packer element under extreme thermal conditions such as a steam injection well.

Exploration and production activity increasingly involves operations in extremely high temperature/ high pressure (HP/HT) and corrosive sour environments. These conditions create a great challenge to downhole sealing components that rely on elastomers or plastics as these materials are prone to degradation when temperatures reach 500°F (260°C) or even lower in fluids. Metal-to-metal seals may have the temperature tolerance, but lack enough elasticity and malleability to provide a reliable downhole seal. The novel alternative discussed in this paper is to fully utilize the high thermal and chemical stability and elasticity of a carbon material, and combine it with nano-reinforcements to enhance the interlayer strength of a carbon matrix. This combination results in an elastic carbon composite and thermal packer that is strong, elastic, and resistant to extrusion, downhole high temperature, thermal cycles and corrosion.

Tests show that the ECC composite has excellent thermal stability up to 1000°F and strong corrosion resistance to most downhole fluids, including hydrocarbons, brines, acids, etc. More importantly, ECC has displayed improved mechanical strength – up to 15,000 psi (1034 bar) – and elasticity (>6%). When compared to elastomers, ECC generates much higher sealing and anti-extrusion forces, and shows significantly less or no stress relaxation at high temperatures. In addition, the low density and self-lubricating property observed from the ECC materials (0.07 coefficient of friction) make it an attractive alternative for dynamic seal products. Seal failure of packer elements at high temperatures and under large well temperature fluctuations is a common and costly problem to the oil industry. The ECC seal elements delivered superior sealing performance in packer tests at high differential pressures above 600°F (315°C) and withstood repeated fluctuations in temperature of 525 Δ°F [273 ΔC].

The novel ECC composite and unique packer elements provide reliable solutions to HPHT sealing challenges in the oil and gas industry.
Rospo Mare Integrated Reservoir Study Italy, Adriatic Sea: An Innovative Approach of Karst System Modeling and History Match
Authors: Bellentani G. , Godi A. , Siliprandi F. , Terdich P. , Famy C. , Fournier F. , Jumeaucourt C. , Leandri P. , Le Maux T.
Published: September 2016

Rospo Mare is a heavy oil fractured karstic carbonate reservoir producing since the 80's. Reservoir pressure is constant due to a strong aquifer tilted toward north east. The producing wells are systematically operated at critical rate to prevent water production (no water treatment installation). The paper is focused on the modeling of the fractures and the karst system in conjunction with an innovative history match approach used to match the forced anhydrous oil production and to represent the complex water position and behavior through time.

As the main fracturing phase of Rospo Mare reservoir occurred before the karstification phase, the dissolution of the carbonates was guided by the existing fracture network. The karst system and the fracture network were modeled together thanks to a fracture model that includes several enlarged fracture sets and lineaments. The fracture modeling was also guided by the relative compactness of the matrix facies distribution. Because of limited data for fracture characterization, the dynamic characteristics of fractures, particularly the aperture of enlarged fractures, were fully considered as history match parameters. The history match approach consisted in using both the historical oil production and the prediction period to make sure that the wells were producing at their critical rate and ensure a realistic displacement of water at both field and well levels. This unusual strategy was necessary because of lack of data to constrain history match (no water and gas production, no pressure variation).

Therefore the history match was performed by taking into account the prediction period through a do nothing case scenario. Based on the assumption of critical rate, a decline of the oil production rate is expected during the prediction period. This allowed assessing the vicinity of water at wells: both the rise of the water table and the coning effect at wells. The matched model successfully honors the water displacement and position at key wells including the last two side tracks drilled in 2012. The model allows a good representation of the reservoir physical behavior and provides a useful tool for piloting the field and assisting future decisions.
Two-Dimensional Visualization of Heavy Oil Displacement Mechanism During Chemical Flooding
Authors: Voroniak A. , Bryan J. L. , Hejazi H. , Kantzas A.
Published: September 2016

There have been numerous laboratory tests conducted in recent years, studying the potential for heavy oil recovery through chemical addition (polymers and surfactants). In these tests, recovery is often understood in terms of pre-water breakthrough and post-water breakthrough improved oil recovery. Pre-breakthrough tests focus on viscous fingering and sweep efficiency from water vs. polymer additives. Post breakthrough tests study the potential for oil recovery after a waterflood has already been run: in these systems surfactants and polymers are added and there is conclusive evidence that chemical additives can be very effective at improving heavy oil recovery at the scale of these core flood systems.

The observation made in laboratory core floods is that chemical recovery of oil is achieved under very high pressure gradients. The mechanism proposed in these tests is that chemicals plug water pathways and lead to improved sweep within the core. In reservoir applications of this technology, these same conditions may not be met and it is unclear whether these chemicals will still be as effective in non-linear systems. This study shows tests run in a 2D Hele-Shaw cell, which displaces oil with no pore scale trapping and with many open flow pathways like what is expected in the field. The objective of running tests in this system is to understand the mechanisms of heavy oil recovery and to observe whether chemical additives can still be successful for producing heavy oil in non-linear core systems with no capillary trapping.
Environment-Friendly Colloidal Nanoparticles for Stabilizing Clays Within Subterranean Formations
Authors: Agrawal D. K. , Kuznetsov O. V. , Suresh R. , Welch J. , Khabashesku V. N.
Published: September 2016

Most producing formations contain clay minerals that can impair permeability due to clay migration and swelling because of their sensitivity to aqueous fluids. Unfortunately, conventional clay stabilizers are inadequate because of their inability in reaching smaller pores, difficulty in handling and disposal, effect on environment and high cost. We show that nanoparticles can stabilize clay particles and prevent clay-related flow impairment. Moreover, these nanoparticles are inexpensive and environmentally friendly, when compared to conventional clay stabilizers.

Sandstone core samples were treated by cationic and anionic colloidal nanoparticle dispersion inside the core holder. A core flooding test apparatus was used to inject nanoparticles in the cores. Differential pressures with and without the nanoparticles treatment were measured across the core samples and compared to determine the effectiveness of the treatment process. Effluents samples were collected at regular intervals and analyzed for the presence of migrated clay particles. In addition, other laboratory measurements such as particles size and zeta-potential were used to understand the interactions of the nanoparticles with the clay particles. Laboratory tests confirmed significant improvements in the stability of clay particles' with the addition of nanoparticles colloids to the aqueous fluid system. We believe this is due to nanoparticle adsorption on the clay particle active sites. On the core flood test apparatus, colloidal nanoparticles stabilized clays in the various sandstone core samples. Significant reduction in permeability impairment was observed after treating the sandstone core samples with negatively or positively charged nanoparticles. A possible mechanism for the reduction in permeability impairment is the attachment of positively charged nanoparticles to the negatively charged clay surfaces, thus pinning clay particles in the pore surfaces. Moreover, negatively charged nanoparticles attach to the positively charged edges of the clay particles, preventing water molecules and ions from intercalation into the clay laminated structures. The combined formulation of cationic and anionic nanoparticles is expected to provide the required durability and performance.

This paper provides a detailed study of nanoparticle and clay interactions in core samples and indicates the nanoparticle utility in mitigating permeability impairment due to clay migration and swelling. The proposed nanoparticles have possible use as formation damage control agents in drilling, acidizing, completion and hydraulic fracturing fluids and in scale inhibitors during squeeze treatment. Another very important application of clay stabilization is low-salinity water flooding.
Using a Problem-Based Learning Approach in Technical Professional Training
Authors: Nelson Jon S. , Musa Ismaeel E.
Published: September 2016

Problem-Based Learning (PBL) is an approach to training that has been used in various industries for more than 40 years though with limited application in the oil and gas industry. PBL has two fundamental goals: 1) to support participants as they learn the required domain skills and knowledge; 2) to support the participants through the process of learning to be self-directed, self-regulating problem-solvers. The first goal should be the minimum expectation of any technical training program. The second goal has more varied utility, since becoming self-directed learners and problem-solvers are not always learning outcomes required of technical training. But when these are required, PBL is the tool of choice.

In this paper we will identify the critical attributes that define PBL; we will briefly discuss when PBL is ideal and when it is not; we will also report on a problem-based, instructional development project conducted at the Upstream Professional Development Center (UPDC) at Saudi Aramco. We will describe the analysis, design, development, and delivery phases of the project with a focus on key processes and products that resulted because of the PBL approach. Lastly, evaluation data will be analyzed and conclusions will be drawn.
A Novel Method of Knowledge Transfer in Challenging Times
Authors: Nunno Nii , Kumar Aniket , Samuel Robello
Published: September 2016

In the current challenging downturn market scenario, many companies have turned their attention towards enhancing the existing training and knowledge transfer programs for their engineers to reduce costs and improve efficiencies. Keeping in mind the increased spending cuts that the industry is facing, the SPE Gulf Coast Section Continuing Education Committee collaborated with leading technical experts in the drilling domain, and came up with a novel development model to transfer knowledge at reduced costs, while simultaneously raising funds for student scholarships.

In order to provide exposure to advance technologies that focus on improving the drilling performance, a ‘Drilling Workshop' was planned for both the young professionals and the experienced engineers. With the objective of maximizing knowledge transfer and learning, the workshop was scheduled as a one-day event having two separate 3-hour sessions, and focused on current interest areas associated with emerging technologies in drilling. The registration fees for the workshop per attendee ranged from $150 to $250 depending on other organizational costs. Overall overheads were low as compared to some of the existing industry training sessions as no expenses were incurred on instructors' fees or venue costs. As an additional incentive for the companies to allow their employees to attend the workshop, free copies of a textbook related to this topic and valued equal to the registration fees, were provided to all the attendees for further enhancing their engineering fundamentals.

This paper will present detailed features of this knowledge transfer model and will highlight ways in which this model can be effectively incorporated and used by other SPE sections to benefit young engineers and experienced professionals in this current downturn market. Over the course of the last 24 months, 10 such workshops were conducted in various SPE sections in the United States to successfully raise about $60,000 in student scholarships for SPE. In addition, a team of five students was financially supported to attend the SPE Annual Technical Conference & Exhibition in Amsterdam in 2014 using the funds raised from the workshop.

This training and development model has the potential of being a great means of knowledge dissemination across the board in the oil and gas industry. These workshops successfully provided a cost-effective means to revisit the technical fundamentals, along with an avenue for continuous learning for engineers, keeping them updated about the latest available technologies in the industry. This paper will be very useful for all the SPE sections globally, helping them adopt this model for knowledge transfer in challenging times.
Using an Innovative Tool System to Estimate In-Situ Permeability and Pressure at Multiple Targets in a Monitoring Well in Permian Basin
Authors: Zhan Lang , Fair Phil , Dombrowski Robert , Quint Edwin , Cao Richard , Cui Qi
Published: September 2016

Permeability in tight sands and shale formations is a critical property that determines well performance, completion methods and field development strategies. Obtaining reliable permeability values in these reservoirs is challenging. Ultra low permeability and very strong stratification or heterogeneity in the formations require conducting long duration tests at multiple locations in a well to obtain a complete reservoir characterization. Because of these characteristics, existing tools or methods that work well for conventional reservoirs may not deliver reliable results. The objective of this work is to develop a technique that can provide permeability and pressure estimations as well as long term reservoir monitoring in multi-layer, tight formations.

An innovative reservoir monitoring and testing tool system was developed and successfully applied to a dedicated reservoir observation well in Permian basin, Texas, USA. The tool system integrates the transient pressure tests for zonal formation property estimation and the long term reservoir performance monitoring in multi-layer, tight reservoirs. The tool string consists of 11 packers that isolated 10 major producing targets in tight sands and shale formations. Volume chambers and pressure sensors were installed in the string to create pressure pulses and record their corresponding responses from the isolated wellbore intervals for estimations of zonal in-situ permeability values and formation pressures. A fit-for-purpose transient pressure solution was also developed to analyze the data whenever the existing commercial software could not handle. Permeability and formation pressures in eight out of ten zones were obtained. The estimated permeability values have a range from tens of nano-Darcy in shale formations to hundreds of Micro-Darcy in tight sand layers, demonstrating the excellent flexibility and suitability of this technology to dynamic reservoir evaluation in tight and shale formations. After the impulse test, hydraulic fracturing operations in a near-by well induced a variety of pressure responses in different isolated intervals at the monitoring well. Strong correlations were obtained among the hydraulic fracturing induced pressure jumps, the zonal permeability values and depletions that were estimated from the earlier test. The results enable us to verify the estimated zonal permeability and formation pressures, pinpoint the height of fracture growth, calibrate fracture design models, improve well/fracture placement and construct a more representative reservoir model for field development optimization.
Thru Tubing Deployed Electrical Submersible Pump with Downhole Wet Connector
Authors: Malone David , Nutter Greg , Algeroy John
Published: September 2016

Electrical submersible pumps (ESPs) are frequently the optimal artificial lift option to cost-effectively maximize reservoir recovery and production. However, the full potential of ESPs in offshore and remote locations has historically been limited by two key challenges: rig deployment and the inability to access the reservoir without pulling the production tubing.

In order to reduce the burden operators face when utilizing ESPs, the company has developed a system that makes installation and retrieval of an ESP as simple as running a production logging tool; radically reducing the cost and downtime associated with ESP workovers by utilizing a lightweight slickline unit instead of a rig or workover unit to replace the ESP.
Completion Design Production Case Study in the Duvernay Shale Formation
Authors: Thomson Jim , Zaslavsky Greg , Leshchyshyn Tim
Published: September 2016

In the last five years the Duvernay formation has become one of the most sought after plays in Canada. This case study takes a closer look at the completion methods and corresponding production of the Duvernay wells near Fox Creek, Alberta, Canada. With the Duvernay being a highly over-pressured reservoir, the completion system is a major component in the success of conducting hydraulic fracturing. In the first two years, different completion tools were applied and after 2012 the vast majority of the completion methods became either the plug and perf cemented liner or the open-hole packer ball-drop systems.

Through the production case study that has been completed, it was found that the open-hole completion method had better cumulative production and rate compared to the plug and perf method by ~23% at 3.5 years, although early time production has similar results. A big component that affects the production and completion method is the lateral length, the total stages and as a combined result, the stage spacing. The lateral reach ranged from 900 m to 3000 m with stage spacing ranging from 25 m to 800 m and production results varying by 253%. The most common number of frac stages per well was 16 stages but the 20 stage wells had 78% more production after 1 year. Interestingly the higher number of stages, (up to 59 per well) had results that deviated substantially below the average, as well as above as expected.

Based on the five-year learning curve, some of the initial wells that were deemed underperformers were re-fractured with new perforation clusters throughout the well placed between the old perforation clusters. A particularly interesting example well re-stimulated with proppant and near wellbore diverter added 254% incremental recoverable gas reserves and 295% more condensate reserves. The results of this re-fracture will be examined as part of this study of current and past completions design.
Phase Behavior of Fluid Mixtures in a Partially Confined Space
Authors: Liu Yueliang , Li Huazhou Andy , Okuno Ryosuke
Published: September 2016

Phase behavior of reservoir fluids in nano-pores of shale can be quite different from that in a bulk space. Its accurate description can lead to more accurate estimation of hydrocarbons in place in shale, as well as better understanding of the mechanisms governing hydrocarbon recovery from shale. This paper presents both experimental and modeling studies of the coupled effects of competitive adsorption, capillary pressure and pore size distribution on the phase behavior of fluid mixtures in partially confined spaces.

Experimentally, we measured the pressure/volume (PV) relationships along isothermal temperatures for fluid mixtures (N2/n-C4H10 and CH4/n-C4H10 binaries) that were contained in bulk spaces (PVT cell) and in partially confined spaces, respectively. To make the so-called partially confined space, the PVT cell was connected to a container holding a shale core sample. The partially confined space consists of the pore space in the shale core and the bulk space in the PVT cell. Theoretically, we developed a phase-behavior model for partially confined fluids by considering competitive adsorption, capillary pressure and pore size distribution of the shale core. In this model, the bulk PVT space is considered to be a capillary tube with an infinite diameter, while the shale sample is deemed to comprise of a series of capillary tubes with various diameters.

Test results show that, at the same temperature, the bubble point pressure of N2/n-C4H10 mixture in the partially confined space is higher than that in the bulk space, while the bubble point pressure of CH4/n-C4H10 mixture in the partially confined space is smaller than that in the bulk space. When a fluid mixture comes into contact with a shale sample, the individual components in the mixture may be preferentially adsorbed onto the shale sample, leading to the competitive adsorption phenomenon. The competitive adsorption of gas mixture onto shale can change the initial mixture composition, and thus affect the phase behavior of the mixture. The theoretical model can be properly tuned to yield bubble point pressures that are well matching the measured ones.
Experimental Study and Modeling of Sand Erosion in the Gas-Liquid Cylindrical Cyclone GLCC Separators
Authors: Arabnejad H. , Sajeev S. , Guimmarra A. , Vieira R. , Shirazi S. A.
Published: September 2016

Gas-Liquid Cylindrical Cyclone (GLCC) separators have been widely accepted as an alternative to conventional vessel-type separator during recent years. The operators are using GLCCs at flow rates higher than the normal recommended operational envelope in applications where the increased liquid carry-over and gas carry-under can be tolerated. Experience gained from production of hydrocarbons with entrained sand has shown that severe degradation of production equipment may occur due to solid particle erosion at high productions rates. However, there are no data and no field feedback on erosion in the inlet region of a GLCC. Thus, the goal of this work is to evaluate the erosion condition in the Gas-Liquid Cylindrical Cyclone (GLCC) separator under gas production and low-liquid loading flow condition.

Erosion experiments are conducted with gas-sand and gas-liquid-sand flow conditions in a laboratory scale GLCC with two particle sizes and gas velocities. An ultrasonic thickness measurement system is employed to monitor the erosion rates at the inlet region of the GLCC. Several cases are simulated with commercially available Computational Fluid Dynamics (CFD) software. Based on the experimental data and CFD simulations, a mechanistic one-dimensional model is proposed to calculate maximum thickness loss inside the GLCC.

It is observed that the location of maximum erosion is not varying significantly with the flow condition with or without the presence of liquid and particle size, while the liquid entrainment can reduce the value of maximum erosion (in mm/kg) by one order of magnitude. The erosion increases with the flow velocity as expected but not with particle size for the particles used in current experiments. CFD simulation results that are obtained by utilizing the mechanistic erosion equations provided fair agreement with experimental measurements for gas-sand condition, and the simplified model showed consistency with the data in both gas-sand and gas-liquid-sand flow conditions.
Improved Optimization Through Procedures as Pseudo Objective Functions in Nonlinear Optimization of Oil Recovery With Next-Generation Reservoir Simulators
Authors: Temizel Cenk , Tiwari Aditya , Kirmaci Harun , Aktas Sinem , Ranjith Rahul , Zhu Ying , Tahir Sofiane , Aminzadeh Fred , Yegin Cengiz
Published: September 2016

Optimization has become a practical component in decision-making processes in field development and reservoir management. Although optimization simplifies decision-making, it harnesses complex equations and formulations that may be computationally expensive to solve. Numerical reservoir simulation adds another dimension to this phenomenon when combined with optimization software to find the optimum defined by an objective function. Considering the fact that current reservoir simulation models are constructed with vast amount of data and if it is coupled with optimization software, computational limits of regular computers can cause not being able to reach the aimed result although the recent technological development allows running huge reservoir models with parallel computing systems. Consequently, it is inevitable to achieve robust and faster results in optimization problems.

Predefined objective functions in optimization software when combined with numerical reservoir simulators attempt to maximize the net present value or cumulative oil recovery defined with an objective function, where the objective function can be defined to be multi-objective leading to Pareto sets consisting of trade-offs between objectives. Using an optimization algorithm with predefined objective functions does not provide the flexibility to the physical reservoir fluid flow phenomenon to "maneuver" throughout the iterations of an optimization process. It is necessary to use a more flexible objective function by introducing conditional statements through procedures.

In this study an optimization software is combined with a commercial reservoir simulator. Conditional statements implemented in the simulator as procedures help the software/simulator combination operate under pseudo-dynamic objective functions that lead to speed and robustness through trying sets of combinations of parameters, and thus achieving conditions that lead to highest recovery within the given time frame as defined by the conditional statement for the condition for which the simulation run is performed. The procedures feature enables implementation of codes by using conditional statements that act as piecewise objective functions, maximizing the recovery and taking into account the timeframe or condition they belong.

A commercial reservoir simulator is used in this study with conditional statements enhancing production in a given timeframe featuring certain conditions. The optimized recoveries with pseudodynamic objective functions provide an enhanced recovery, as compared to that of an optimization case with predefined constant objective function in the optimization software throughout the iterations of the optimization and simulation process.
Technology to Remove Asphaltene, Resin and Paraffin Deposits in Wells Using Organic Solvents
Authors: Khaibullina Karina
Published: September 2016

At the moment, most of the oil fields of the Russian Federation are in their late stage of development. This stage is accompanied by a number of complications for oil, including those associated with the formation of asphaltene, resin and paraffin deposits (ARPD) in downhole equipment. These deposits significantly affect the geological, physical and technological conditions of the oil fields development. They reduce the flow rate of the wells, increase water cut production and produce organic depositions, such as the ARPD

There are two methods to struggle with the ARPD in oil production: 1- remove the formed deposits and prophylaxis (prevention) by applying thermal and chemical methods. 2- prevent the formation of the ARPD – by using the inhibitors of these deposits (dispersants, depressant, wetting agents and modifiers).

One of the most effective and advanced methods for the removal of the ARPD in the wells is the use of hydrocarbon solvents, the selection of which is usually done experimentally.

For selecting an effective solvent in order to remove the paraffin, the composition and type of ARPD are needed to be known. The samples are selected from the oil field of the Orenburg region and ARPD analysis of the samples was conducted. The method of analysis is based on the different solubility of the components in the sediments of certain solvents. Determining the composition of the ARPD has done with the residual oil method by Marcusson.

In th result of our experiments we recognized that the type of deposites are the Paraffin.

To operate the process of the dissolution and removal of paraffin deposits, we find out that it is better to make a solvent with the composition of aromatic and aliphatic hydrocarbons, with the addition of surfactants. With adding a nonionic surfactant to the solvent can be improved the detergency and dispersancy of the solvent. The results of our experiments showed that with using the created solvent with the composition of aromatic, aliphatic hydrocarbons and surfactants, it is possible to remove the orgnic deposits specially paraffin effectively.
A utilização da Pista Direta de Planas no tratamento precoce da mordida cruzada posterior: relato de caso
Authors: Garbin Artênio José Isper , Wakayama Bruno , Rovida Tânia Adas Saliba , Garbin Cléa Adas Saliba
Published: September 2016

A mordida cruzada posterior é considerada a mais prevalente dentre as oclusopatias,  e, se não tratada precocemente pode acarretar em alterações craniofaciais significantes na fase adulta, comprometendo toda a estrutura estomatognática. Objetivou-se relatar dois casos clínicos de mordida cruzada posterior funcional, com a utilização das Pistas Diretas de Planas como tratamento, a fim de determinar sua eficácia e estabilidade oclusal. O 1º caso clínico refere-se a uma paciente de 6 anos, com mordida cruzada posterior funcional unilateral esquerda e desvio de linha média. Em vista ao protocolo da Reabilitação Neuroclusal e a utilização das Pistas Diretas de Planas como tratramento, foram realizadas as remoções dos contatos prematuros dos dentes 64 e 65. Em seguida foram confeccionadas as Pistas Diretas Planas nos respectivos dentes, em planos inclinado a fim de determinar a correta estimulação neuromuscular e promover o equilibrio funcional do sistema estomatognático.  Após 63 dias  houve a correção da mordida cruzada e o caso foi acompanhado por 2 anos. O 2º caso clínico  refere-se a uma paciente de 3 anos, com mordida cruzada posterior funcional unilateral direita e desvio de linha média. Seguiu-se o mesmo protocolo de tratamento com a Reabilitação Neuroclusal e confeção das Pistas Diretas de Planas descritos no caso 1, e após 95 dias houve a correção da mordida cruzada posterior e o acompanhamento foi de 2 anos. Conclui-se que as Pistas Diretas de Planas foram eficazes nas correções das mordidas cruzadas posteriores nos dois casos relatados, garantindo a harmonia oclusal e a sua estabilidade após o tratamento.Descritores: Má Oclusão; Ajuste Oclusal; Diagnóstico Precoce.
Dental changes in Class II patients treated with Pendex appliance: a prospective study
Authors: Silva Flávio Luis Goulart Ribeiro da , Barbosa Helga Adachi Medeiros , Oliveira Derly Tescaro Narciso de , Bertoz André Pinheiro de Magalhães , Faltin Júnior Kurt , Bigliazzi Renato
Published: September 2016

O objetivo deste estudo foi avaliar as alterações dentárias na maxila e as possíveis alterações verticais decorrentes da utilização do Pendex como método de tratamento ortodôntico para distalização dos molares superiores. Uma amostra por conveniência de 10 pacientes de ambos os sexos (9,3 - 28,8 anos; média: 15,3 anos), com necessidade de tratamento ortodôntico, foi selecionada para participação desse estudo na Faculdade de Odontologia da Universidade Paulista – FOUNIP. Duas radiografias em norma lateral foram obtidas de cada paciente, uma ao início do tratamento (T1) e outra após a distalização dos molares dos primeiros molares superiores (T2). Os cefalogramas foram traçados e mensurados pelo mesmo operador e os dados de T2 e T1 foram comparados entre si, para cada paciente. As seguintes medidas cefalométricas foram avaliadas: distância de PTV ao 1o molar superior (A6-PTV), ao 1o pré molar superior (A4-PTV) e ao incisivo central superior (A1-PTV), inclinação do 1o molar superior (A6.PP), inclinação do 1opré molar superior (A4.PP) e a inclinação do incisivo central superior (A1.PP) em relação ao plano palatino (PP), ângulo interincisivo (A1.B1); altura facial inferior (AFI); eixo facial (EF); altura facial total (AFT). Os dados obtidos foram submetidos ao teste “t” para amostras pareadas (5%). Os valores médios e desvios-padrão obtidos para cada medida (T2-T1) foram: A6-PTV= - 4,9±6,5; A4-PTV=1,2±4,1; A1-PTV= -1,4±7,3; A6.PP=9,4±7,7; A4.PP=-3,6±6,7; A1.PP=9,4±7,7; A1.B1=-4,9±13,7; AFI=1,7±2,1; EF=-1,0±2,4; AFT=1,0±2,7. Os resultados mostraram significância estatística para: A6-PTV (p=0,041); A6.PP (p=0,004) e AFI (p=0,031) (p>0,05). Pôde-se concluir que Pendex mostrou-se eficiente na correção da Classe II e que seus efeitos foram limitados às estruturas dentoalveolares.Descritores: Má Oclusão de Angle Classe II; Ortodontia; Cefalometria Craniana.
Antropometria e aptidão física: comparação entre praticantes e não praticantes de escolinhas esportivas
Authors: Miodutzki Anderson , Souza William Cordeiro de , Grzelczak Marcos Tadeu , Mascarenhas Luis Paulo Gomes
Published: September 2016

A prática regular da atividade física contribui para o desenvolvimento da aptidão física e previne a obesidade. Sendo assim, no presente estudo objetivou-se comparar as características antropométricas e de aptidão física relacionada à saúde entre crianças praticantes e não praticantes de escolinhas esportivas. A amostra foi constituída por 60 alunos de ambos os gêneros, com idade entre 7 e 12 anos da cidade de São Bento do Sul - SC, os quais foram divididos em dois grupos: 30 praticantes e 30 não praticantes regulares de exercícios físicos. Na avaliação antropométrica coletou-se a massa corporal e estatura para calculo do índice de massa corporal (IMC). Para obtenção das aptidões físicas foi avaliada a flexibilidade, o testes de força (resistência abdominal) e por fim, o teste de resistência cardiorrespiratória (6 minutos). Os tes­tes foram realizados atendendo as recomendações sugeridas pelo PROESP-BR. Os dados foram analisados através de estatística descritiva de média e desvio padrão. Foi aplicado o Teste t de Student no comparativo entre praticantes e não praticantes e o teste de qui-quadrado para determinação de diferenciação no percentual de classificação, com nível de significância es­tabelecido em (p<0,05). Os resultados apresentados demonstram que o grupo praticante apresentou diferença significativa apenas na variável antropométrica de estatura e na aptidão física de força (resistência abdominal) quando comparado ao grupo não praticante. Desta forma, pode-se concluir que apenas a estatura e a força (resistência abdominal) dos praticantes diferem estatisticamente do grupo não praticante. As demais variáveis apresentaram valores estatisticamente semelhantes.Descritores: Antropometria; Aptidão Física; Exercício.