bluuebunny/crossref_metadata_2025 huggingface dataset:
Review of Professional Engineering in Petroleum Engineering
Authors: Kinney Lance , Norwood Catherine
Published: October 2018

Many individuals who practice in the field of oil and gas production, transportation, and refining perform engineering tasks and activities but do not become licensed as Professional Engineers for a variety of reasons, such as statutory exemptions, corporate policies, or lack of understanding of the value of professional practice in an area with a high potential impact on health and safety. This paper uses information from state boards of licensure, national organizations related to petroleum engineering, and case studies to address these misunderstandings related to licensure. The value of licensure as a Professional Engineer in the area of petroleum engineering is summarized, including statutory requirements and exemptions to practice in various U.S. states. The licensure process for Professional Engineers is explained, including education, experience, and examination requirements. Professional practice and ethical standards are discussed. While some jurisdictions do not specifically require licensure to practice in the area petroleum engineering, there are a number of advantages for individual practitioners to become licensed as a Professional Engineer. Examples are provided to explain how professional engineering licensure can protect the health, safety, and welfare of the public, as well as benefit the individual practitioner and industry as a whole.
Developing a New Technique for Calculating Accurate Water Saturations from Well Logs in Source Rocks
Authors: Hillier Ryan , Vosburgh Eric , Warrington Daniel , Ibrahim Mazher
Published: October 2018

Determining log-based water saturation using Archie's (1942) equation, or any derivative shaly sand method, requires correct inputs to produce valid results. In resource plays, the rock matrix is composed of water wet and oil wet constituents, therefore, correct values of Archie's cementation factor (m) and saturation exponent (n) are critical. In practice, it is pragmatic to use the Pickett plot (Pickett, 1973) to set connate water resistivity (Rw) and Archie's ‘m’. However, it is difficult, if not impossible, to derive Archie's ‘n’ parameter without additional information. Research combining core and log data shows evidence of a positive correlation between Archie's saturation exponent and the total organic content (TOC) in a given unit volume. Using this relationship, Archie's equation may be used to define a variable ‘n’. It is hypothesized that ‘n’ increases with increasing TOC volume as a result of an interruption of electrical pathways that resistivity tools exploit. This disruption results in an increase in the apparent value of ‘n’ required to compute correct water saturations. Due to the apparent excess resistivity in organic-rich rocks, an increase in ‘n’ values or kerogen corrected resistivity is needed to produce a fit to core-derived water saturations. This article will demonstrate the methodology used to derive a variable ‘n’ parameter and kerogen corrected resistivity in an organic-rich interval.
Who Are the Innovators in the Upstream Oil & Gas Industry? Insights From the 2017 SPE Global Innovation Survey
Authors: Perrons Robert K. , Burgers Henri , Newton Cameron
Published: October 2018

Technology and innovation are playing increasingly important roles in the success or failure of tomorrow's upstream oil & gas firms. Building upon the successful first SPE Innovation Survey in 2012 which looked at innovation at the business unit level, a second survey was carried out in 2017 to examine these processes again within the industry, but this time from the point of view individual people. This paper uses data from the 2017 survey to find out who the "explorers" are within the oil & gas sector that seem to be hardwired to deliver tomorrow's bolder technologies, and who the "exploiters" are that, for whatever reason, find it more difficult to bring about significant technological change within the industry. We found several potentially useful patterns in the data. First, people with graduate degrees are noticeably more likely to engage in exploration kinds of behaviors than people who do not. Second, respondents who spent their formative years before the age of 18 in Norway, Russia, or Indonesia report having more exploration kinds of activity than most others. Third, people currently working in Brazil, China, Malaysia, Nigeria, and Venezuala all reported lower levels of exploration-like behavior than their counterparts elsewhere. And expatriate employees seem not to be any more predisposed to exploration activities than non-expatriates. The paper concludes with a discussion about the 2017 survey's methodological shortcomings and, based on those, recommendations for future investigations in this area.
Integrated Well Integrity Cement Evaluation Technique for Shallow Gas Flow Cementing in Eagle Ford Field
Authors: Dooply Mohammed , DeBruijn Gunnar , Martinez James
Published: October 2018

Cement job design has historically been a static process largely independent of the other processes in the drilling and completion phases. The success or failure of achieving zonal isolation, which is the main objective of cementing, is usually attributed to the cement placement result without analyzing in details various factors such as drilling parameters, borehole shape, drilling fluid properties, casing designs, formation properties (temperature and pressure profiles), and even cement evaluation methods including post-cement placement activities that could contribute to the end result of achieving zonal isolation objectives for long-term well integrity on an oil and gas well.

A unique workflow is developed by incorporating data from different stages of the well construction process (drilling, cementing and cement evaluation) to optimize the cement job design and placement evaluation for critical and challenging wells. By integrating real-time or near real-time data from drilling and cementing phases, the unique workflow rapidly identifies critical information that can prevent poor cement placement, which allows operators to make timely decision to achieve well integrity and safe working environment.

An integration of drilling and openhole information, cement slurry design and placement/mud removal result, and cement evaluation log evaluation is required to better understand zonal isolation and well integrity, particularly for wells with shallow hazards. This case study explains an integrated workflow implemented during cement placement design and evaluation on surface casing cementing job after failure of a conventional cement barrier placement in the Eagle Ford field in south Texas.
Estimating Hydraulic Fracture Geometry by Analyzing the Pressure Interference Between Fractured Horizontal Wells
Authors: Seth Puneet , Manchanda Ripudaman , Kumar Ashish , Sharma Mukul
Published: October 2018

Pressure interference measurements in fractured horizontal wells have been used to characterize hydraulic fractures (Kampfer and Dawson, 2016; Roussel and Agrawal, 2017). Past work has modeled this interference using static reservoir gridblocks as a proxy for hydraulic fractures. In this paper, we show that to accurately interpret the pressure response observed in a fractured monitor well, one needs to explicitly model the fractures and their propagation as a compliant discontinuity in the reservoir.

A fully-coupled 3-D geomechanical reservoir model which models fractures explicitly as open and compliant channels has been developed to simulate pressure interference between hydraulic fractures in a multi-well pad. Using this model, we simulate dynamic fracture propagation at the treatment well while monitoring pressure at the monitor well. The pressure response inside the monitor well fracture is calculated accurately by explicitly modeling the monitor well fracture as a compliant discontinuity in the reservoir rock. We study the impact of mechanical stress interference between the fractures. The model is then used to simulate and analyze the treatment pressure response observed in a pair of wells in the Permian Basin.

Simulation results indicate that hydraulic fracture propagation towards the monitor well results in changes in stress on the monitor fracture. Closure and opening of the monitor fracture is manifested directly as an increase/decrease in pressure in the monitor well fracture. We show that this pressure change in the monitor well is observed primarily because of the elastic effect of mechanically squeezing the monitor fracture by the dynamically propagating hydraulic fracture (not by direct hydraulic communication). As such it is essential to model the compliance of the fractures as has been done in this study. This monitor well pressure response is systematically analyzed to estimate fracture geometry for field data obtained from a Permian Basin well pad.

Our representation of the propagating hydraulic fracture and the monitoring well fracture as compliant discontinuities in the reservoir is for the first time shown to be essential to capture the pressure response observed in the field. Previous models have simplified the problem by representing the fracture as static reservoir grid-blocks, and such models are clearly inadequate. Our model captures the impact of a propagating hydraulic fracture on the pressure response observed in a fractured monitor well much more accurately. Such pressure interference analysis can provide operators with a semi-quantitative estimate of hydraulic fracture geometry, relatively inexpensively.
Grid Cluster in the Office: High-Performance Computing for Reservoir Management
Authors: Yaubatyrov Ramil , Babin Vladimir , Liya Akmadieva
Published: October 2018

Optimal reservoir management usually requires evaluation of a large number of various development scenarios. This applies to a choice of well placement and settings configuration, waterflooding strategy and history matching process. Reservoir models are commonly used to obtain field production forecast depending on the development plan. Generally, a specialized external high-performance computational environment is used to accomplish the aforementioned multivariate calculations, while personal workstations stay idle most of the time. We propose an alternative way of organizing HPC environment using available computational resources. The method is based on integration of several personal workstations into a so-called grid cluster using local network, which allows managing the whole system from any connected node. Each computational node is provided with a flexible timetable to ensure that distributed calculations do not interfere with daily work. The solution does not require additional capital investments and is easy to implement in the office. Although initially designed for hydrodynamic simulations, the system can be used for any time-consuming multivariate task.

Proposed method has been applied to several optimization cases of real fields. Grid cluster consisting of fifty nodes with estimated peak performance of 60 TFLOPs was used to find optimal development plan for a field in Western Siberia, allowing to reduce computational time from several months to one weekend. The system prooved linear speedup depending on the number of involved workstations along with stability under conditions when each node may connect or disconnect at any time.
Proven Experience in Construction of Multilateral Wells Using TAML 1 Technology in Novoportovskoye Field
Authors: Pilnik Sergey , Dubrovin Andrey , Zimoglyad Mikhail , Bulatov Fuat , Burkov Fedor , Abaltusov Nikolay
Published: October 2018

The key opportunity of Novoportovskoye Field is hydrocarbon reserves, which remain undeveloped. In this field, significant oil reserves directly underlie massive gas caps. Economic efficiency in such geological conditions is based on the use of new technologies for the maximum extension of field infrastructure loading.

This paper reviews prerequisites and cases of multilateral well drilling technologies as an efficient EOR method at Novoportovskoye Field. The paper summarizes the results of drilling of nine multilateral wells.

The strategy of multilateral well completion at Novoportovskoye Field increased the level of complexity defined by technology advancement for multi-laterals (TAML). First, a multilateral well with an openhole lateral was drilled. This openhole section collapsed when the well was brought into production at the target drawdown. Therefore, the second stage was to construct a multilateral well with cased main bore and lateral using TAML-1 technology.

A version of TAML-1 technology developed by a Russian manufacturer was adapted and implemented at this stage.

Several sidetracking methods were tested to reduce the rig time and multilateral well construction costs. Application of rotary steerable systems (RSS) for sidetracking instead of conventional rotary assemblies and downhole motors enabled to reduce the average sidetracking time from 70 to 30 hours. The record time of sidetracking using RSS was 16 hours.

The history of Novoportovskoye Field development demonstrates a continuous trend towards increasing horizontal section lengths from 1,000 to 1,500 and 2,000 meters. The cumulative multilateral well drilling experience enabled construction of a well with four laterals with a total length of horizontal sections of 4,411 meters. It was the first well with four laterals in Russia built according to TAML-1 technology.

As compared to conventional horizontal wells, the highest initial incremental oil rates were registered in multilateral wells drilled in the Jurassic Yu2-6 interval and the Cretaceous NP2-3 interval of the Novoportovskaya Formation. Considering that the share of the Yu2-6 interval in the oil reserves of Novoportovskoye Field is 46% and the share of the NP2-3 interval is 17%, the operator decided to increase the share of multilateral wells to develop these intervals.

The project objective for 2018 - 2020 is to increase the number of cased holes, to separate laterals to the maximum possible distance, and to improve the completion level to TAML-4.
Improving the Understanding, Application and Reliability of the Perforate, Wash and Cement Technique through the Use of Cement Bond Logs, Tool Enhancements and Barrier Verification via Annular Pressure Monitoring
Authors: Lucas Alexander , Stokkeland Thore Andre , Jackson David , Ingram Scott
Published: October 2018

The Perforate, Wash and Cement technique has been widely applied to remediation of annular cement in recent years. Since 2012, extensive experience in the different technologies currently available on the market has been obtained across ten fields in the Danish and UK sectors of the North Sea and the data obtained has been used to attempt to better understand the effective operational window for the technique, and also further enhance reliability and tool robustness.

The run data obtained from several wells has been calibrated against cement bond logging (CBL) responses so that the degree of annular bonding as inferred from the logs may be expressed in terms of the degree to which hydraulic communication or circulation is permitted via perforations and along the annulus. This in turn helps clearer decision criteria to be defined prior to execution that aids in the selection of the most appropriate method for remediating the cement, since Perforate, Wash and Cement may not be the most suitable technique in every case.

Given the criticality of cement remediation to the long-term success of zonal isolation, it is important to demonstrate that effective hydraulic communication with the annulus has been established during the washing phase to ensure that the zonal isolation medium (cement) can be effectively placed and the hydraulic seal re-established, resulting in successful remediation.

Post-execution verification of the effectiveness of remediation is typically performed via Cement Bond Logging. However, this may not always be a definitive verification step since Cement Bond Logging interpretation does have its limitations (both physical and interpretative), and hence annuli have occasionally been known to develop Sustained Casing Pressure even shortly after positive log interpretations following well-executed cementations.

This paper therefore further demonstrates how Sustained Casing Pressure monitoring can be used as a further criterion to verify the integrity of the remediated annulus and hence conclusively demonstrate whether the washing and later cementing of the annulus has been effectively performed. This in turn is used as definitive confirmation that zonal isolation has been performed within the operating limits of the tool and hence qualify Perforate, Wash and Cement as a robust and viable remedial method.
An Equation of State to Model Microemulsion Phase Behavior in Presence of Co-Solvents Using Average Solubilization Theory
Authors: Ghosh Soumyadeep , Chawathe Adwait , Thach Sophany , Linnemeyer Harold C. , Tao Emily B. , Dwarakanath Varadarajan , Ambastha Anil , Arachchilage Gayani Pinnawala
Published: October 2018

Co-solvents are used with surfactants in modern chemical enhanced oil recovery (CEOR) formulations to avoid formation of viscous microemulsion phases (and reduce costs) in porous media. Modeling the effect of co-solvents on phase behavior is critical to CEOR reservoir simulations. The state-of-the-art is to use HLD (Hydrophilic Lipophilic Difference) with a modified form of NAC (Net Average Curvature) as an Equation of State (EoS) to model microemulsion phase behavior. In this paper, we use an alternative EoS flash algorithm and couple it with an alcohol partitioning model to predict physical phase behavior.

In this paper, we show that the net curvature equation in NAC is not valid for overall compositions away from typical experimental conditions, specifically in Type I and II systems. Alternatively, we use experimental evidence to correlate the harmonic average of oil and brine solubilization ratios to HLD. We use the average solubilization ratio equation with boundary conditions that allow for microemulsion phase type regions to be well defined, thus making the flash calculations robust. To model the co-solvent effect, we couple the newly developed average solubilization theory (AST) based EoS with the Prouvost-Pope-Rouse model to capture co-solvent partitioning across oil, brine and microemulsion phases. The resulting AST theory allows for a HLD based EoS to predict physical two-phase regions with no discontinuity in phase behavior thereby making it a more robust alternative to HLD-NAC. We used 80 phase behavior experiments over a wide range of hydrocarbons and temperatures to validate our approach. The coefficient of determination between the actual experimental data and the predicted model output was found to be above 0.9.
Comprehensive Multi-Stage Analytical Treatment of Steam-Assisted Gravity Drainage SAGD
Authors: Zargar Zeinab , Ali S. M.
Published: October 2018

A comprehensive analytical model of the Steam-Assisted Gravity Drainage (SAGD) process is developed, encompassing steam chamber rise, sideways expansion, and the confinement phases. Results are validated using experimental and field data.

A new analytical model for predicting steam chamber rise velocity and oil production rate during this period is developed. In this theory, by combining volumetric oil displacement with Darcy oil rate considering the indirect frontal instability effect, the rise velocity, and the steam chamber height are calculated. The model is extended to predict oil production, heat or steam injection rate, heat consumption and Cumulative Steam-Oil Ratio (CSOR) during this phase. The model results show the CSOR decreases, with an increasing oil production rate. The rise velocity increases with an increase in permeability and temperature. Results are validated with experimental and field data.

The sideways steam chamber expansion is treated by a new analytical approach which is called Constant Volumetric Displacement (CVD) where injection rate must be increased continuously for a constant oil rate. At the final stage, adjacent chambers interfere, reducing the effective head for gravity drainage and the heat requirement in this system. For a small well spacing, confinement occurs earlier, heat loss starts decreasing sooner, resulting in a lower CSOR, than for a large spacing.

The above analytical SAGD models including rise, lateral spreading, and confinement phases are combined to obtain the Comprehensive Constant Volumetric Displacement (CCVD) model. The results are validated against experimental and field data. Excellent agreement was obtained with laboratory and field results.
ESP Energy Efficiency Analysis on Western Siberia Fields
Authors: Khabibullin Rinat , Sarapulov Nikolay
Published: October 2018

The paper is devoted to the estimation of energy efficiency of wells equipped with ESP at different operating conditions in Western Siberia. As a measure of energy efficiency, the overall efficiency of the wells equipped with ESPs was used. The ESP efficiency can be defined as the ratio of the useful hydraulic power developed by ESP to electric power consumed by the ESP on the surface. Corporate production monitoring systems have evolved significantly in recent years in Gaspromneft [1]. Large amount of production data has been gathered and processed, including well operation and energy consumption data. It allows to analyze ESP's energy efficiency for each well. This analysis has been focused on comparison of different ESP operating modes – continuously operating mode (COM) – standard ESP working mode and periodic short-term activation (PSA) mode [2]. ESP in PSA mode starts and stops frequently – an average start stop period less that one hour.

The analysis showed that at the current time the information gathered during the monitoring of wells is sufficient to conduct energy audit of the equipment at the level of ESP efficiency evaluation. It makes it possible to identify the dependencies between equipment operation parameters and evaluate the operation efficiency under various operating conditions. Energy efficiency estimation can be used to make decisions for the well stock efficiency improvement. For example, in the course of the analysis, a number of results were revealed: the efficiency in the operation of a well in a periodic short-term activation mode (PSA) in comparison with a continuously operating mode (COM) on a low rate wells is higher by an average of 20%; With the increase in water cut, the EPS's energy efficiency is increasing, both in terms of PSA and COM; The average EPS's energy efficiency decreases with increasing rotating frequency; with an increase in run life, the efficiency of the ESP system is smoothly reduced by an average of 5% in three years, after a gain of 1,300 days, the rate of decrease in efficiency is significantly increased; on COM wells with a motor load of less than 40% efficiency is dramatically reduced, so it is recommended to transfer this fund to the PSA; there is a potential for increasing efficiency and oil production at a low rate wells by using ESP with larger nominal rate in PSA mode and reduced the ratio of operation and accumulation periods. Finally, the efficiency analysis can be used to rank ESP manufacturer by energy efficiency in specific conditions.
SNL Application for Production Logging in Hard-to-Recover Gas Reserves Wells
Authors: Zhurilin Andrey , Dmitruk Vladimir , Mironova Eugenia , Minakhmetova Roza , Aslanyan Irina , Nagimov Vener , Shigapov Ilnur , Aslanyan Arthur
Published: October 2018

Determination of Unit T1-2 (Turonian) flow characteristics in Yuzhno-Russky oil and gas condensate field is a priority area in the development process monitoring. This paper is focused on the informative value of downhole logging surveys conducted for assessment of the reservoir and wellbore flow geometry in the well after hydraulic fracturing. A more detailed consideration of this matter has become possible due to the extensive use of integrated logging suite data during estimation of input parameters for interpretation of pressure transient analysis results.

The difficulty of this task was due to the fact that the extent of the vertical fracture in the Turonian formation was several times larger than the perforation zone and, as a result, estimation of the actual net pay based on the conventional logging suite data was hardly practicable. Besides that, due to poor perforation quality the geometry of fracture flow from the reservoir was affected. In view of this, Spectral Noise Logging technique was applied to estimate the reservoir effective thickness contributing to the flow through the fracture created as a result of the hydraulic fracturing job.

The integrated logging suite supplemented with SNL-HD tool was run at several differential pressures. As a result of SNL-HD and HPT surveys and subsequent flow modelling, valuable information on fracture flow rates was successfully obtained.
The Role of Chemicals Loss in Sandstone Formation in ASP Flooding Enhanced Oil Recovery
Authors: Zhong Huiying , Yang Tingbao , Yin Hongjun , Fu Chunquan , Lu Jun
Published: October 2018

Chemical combination flooding technique especially alkali/surfactant/polymer (ASP) flooding has proven to be an indispensable way to enhance oil recovery (EOR). The progress of this flooding technique in Daqing Oilfield (China) shows that it is promising to keep production from falling and help oil companies make profit in a low-oil-price era. However, the ASP chemicals chromatographic separation and loss in sandstone formation are still the weaknesses in the promotion of ASP flooding.

Laboratory investigations for characterizing the behavior and distinction of chemicals loss in sandstone reservoir with strong base (NaOH) and weak base (Na2CO3) ASP flooding were recently carried out. The experiments were designed to pointedly study the chromatographic separation, and consumption loss behaviors of alkali and surfactant in sandstone reservoirs with ASP flooding. Furthermore, the incremental oil recovery factor in heterogeneous sandstone reservoirs with strong base (NaOH) and weak base (Na2CO3) ASP flooding process was evaluated and compared. The loss rates of chemicals and the permeability damage degree in various experiments were determined respectively, the consumption loss mechanism and influencing factors were discussed, and the formulation composition and slug combination patterns were also optimized. Then, the role of ASP chemicals loss in sandstone formation during ASP combination flooding EOR process was worked out.

The results indicated that the chemicals loss behaviors could be weakened and the chemicals chromatographic separation phenomenon could be alleviated in weak base (Na2CO3) ASP flooding, and the average loss rate of alkali and surfactant could drop 9.61% and 15.67% respectively in heterogeneous sandstone reservoirs comparing to strong base (NaOH) ASP flooding. The profitable EOR effect could also be obtained with weak base (Na2CO3) ASP flooding, and the enhanced oil recovery could still reach 20% or more. Moreover, an approximately 15% reduction in permeability damage rate could be realized in the weak base (Na2CO3) ASP flooding instead of strong base (NaOH) system, and the reservoir flow assurance issues related to chemicals loss behaviors could be addressed. The optimal design of ASP formulation and slug combination pattern could technically and economically achieve high oil recovery in sandstone reservoirs with weak base (Na2CO3) ASP flooding.

The results are beneficial to well understand the chemical combination flooding mechanism and can contribute to the existing knowledge in the chemicals super additive effects during EOR process, and it is also significant to further improve the oil displacement efficiency and reduce the injection cost in heterogeneous sandstone reservoirs with weak base (Na2CO3) ASP flooding process.
Using EPR Technique for Monitoring of ISC Processes and Reservoirs Temperature in Enhanced Oil Recovery
Authors: Mehrabi-Kalajahi Seyedsaeed , Varfolomeev Mikhail , Yuan Chengdong , Pu Wanfen , Rodionov Alexander , Orlinskii Sergei , Wang Ruyan , Gafurov Marat
Published: October 2018

The monitoring of the combustion front in in-situ combustion (ISC) processes is important for the precise control of the air injection to make sure that the combustion process occurred in the expected direction. Our previous study showed that the free-radical signal obtained by Electron Paramagnetic Spectroscopy (EPR) measurements might be applied to determine the direction of combustion front. Therefore, in this study, the feasibility of using EPR as a new and fast technique for monitoring combustion front was further investigated. For this purpose, the oxidation process of different types of crude oils was studied in the low-temperature range from 25 to 180 °C. Free radicals concentration was measured using EPR technique for each sample before and after the isothermal oxidation. The results showed that there is some dependence between the free radicals concentration and temperature. For all the tested crude oils, the concentration of free radicals produced in oxidation process increased with temperature. In a real air injection process, the combustion process inevitably leads to an increase of reservoir temperature. The zone in the moving direction of the combustion front will have a higher temperature than other zones. The increased free-radical concentration can be an indication of the increase of reservoir temperature. Therefore, it is possible to estimate combustion front by analyzing free radicals signals using EPR technique. However, there is no universal relationship being found in this study for different types of crude oils because the sensitivity of EPR technique to oxidation processes strongly depends on the composition of crude oil. That is to say, for each crude oil, we need to find its own dependence between reservoir temperature and free radicals signal for the estimation of the combustion front. Also, it was found that a higher content of asphaltenes resulted in a more significant change of the free radicals concentration with temperature as the asphaltenes can stabilize and increase the lifetime of free radicals due to the presence of π-systems. This implies that the monitoring of the combustion front using EPR technique will be easier and more precise for the oil with a high content of asphaltenes.
Effect of Natural Amphiphiles in Resins on Asphaltene Stability
Authors: Abilova Guzaliya , Milordov Dmitriy , Yakubova Svetlana , Tazeeva Elvira , Yakubov Makhmut
Published: October 2018

The resins of heavy sour crude oils with high vanadium and nickel contents have been investigated. Using original procedure, the concentrates of organonitrogen bases with various compositions and molecular masses have been recovered. The effect of the concentrates on the colloidal stability of the oil to asphaltene precipitation has been studied. Kinetic studies using UV spectroscopy have shown that organonitrogen bases, as well as natural amphiphiles in resins affect asphaltene aggregation and decrease the rate of their precipitation in the solvent/flocculant system.
Novel Well Monitoring Technology Implementation for Multi-Zonal Well in Carbonate Kharyaga Oil Field
Authors: Zoshchenko Oleg , Trushin Yury , Aleshchenko Anton , Mukhametshin Ilkam , Galimzyanov Artem , Nukhaev Marat
Published: October 2018

The Kharyaga oilfield is a large oilfield in terms of its geological resources and a very complex one in terms of its geological characteristics. It is located on the territory of the Nenets Autonomous District. The main production target is carbonate formation which is complex in structure and characterized by a high heterogeneity. Factors such as high-paraffin crude oil, aggressive components in associated petroleum gas (hydrogen sulfide), thick permafrost horizons and harsh weather conditions make the Kharyaga field development technically challenging. The development of the above-mentioned field is characterized by an uneven oil recovery of interlayers and by early water breakthroughs in the highly permeable reservoir sections. Various technologies can be used to monitor well performance.

The article presents the results of the pilot project for the new technology introduction of well performance monitoring. This technology proves successful in cases when traditional industrial geophysical methods of well survey can not be applied for various reasons.

Monitoring of the pilot directional well completed with a cemented casing was carried out using the inflow profiling technology based on chemical intelligent markers. These chemical markers were installed on the well completion elements. Polymer matrices, as well as markers, are placed on the outer side of the casing column in the reservoir intervals with a casing. After casing cementing and perforating through polymer matrices in the producing zone, a large-volume selective acid treatment with 15% hydrochloric acid, inhibitors and diverters was injected. The technology of intelligent inflow tracers is used to monitor the well performance for a long period of its productive time and allows solving the following range of tasks: the inflow distribution by intervals, the calculation of water breakthrough intervals, and the evaluation of the well intervention effectiveness [1].

For the first time in Russia, the directional well was studied using tracers installed behind the production casing. It was followed by cementing, perforation and acid treatment of the bottomhole area.
Multistage Hydrofracturing Efficiency Analysis and Horizontal Well Inflow Profiling Using Spectral Noise Logging Technique
Authors: Andreev Alexey , Kamalov Artur , Zaripov Ansar , Kanyukov Dmitriy , Vyhristyuk Sergei , Yuvashev Albert , Aslanyan Irina , Minakhmetova Roza , Trusov Alexander , Maslennikova Yulia
Published: October 2018

One of the most cost-effective technologies used during the development of hard-to-recover reserves is horizontal drilling with multistage hydraulic fracturing. This paper is dedicated to the assessment of multistage hydraulic fracturing effectiveness in formations with low-permeability and high clay content.

The paper demonstrates how the integrated logging suite supplemented with High-Definition Spectral Noise Logging tool can provide valuable information on the flowing reservoir zones behind the liner and therefore the multistage hydraulic fracturing effectiveness.

Based on the results of logging survey carried out in flowing regime with nitrogen being injected into the well, the hydraulic fracturing job performance was assessed and the inflow intervals were identified. As a result of the multistage hydraulic fracturing job, incremental oil production was achieved. On the basis of an integrated logging survey and field data analysis, the integrity of well completion elements was also checked.
Selection of Optimum Monitoring Technique for Wells with Multistage Hydraulic Fracturing on Priobskoe Oilfiel
Authors: Kolupaev Dmitry , Uchuev Ruslan , Bikkulov Marsel , Matevosov Mikhail , Sheremeev Alexander , Mukhametshin Ilkam , Galimzyanov Artem , Nukhaev Marat
Published: October 2018

With the development of well drilling and completion technologies multistage hydraulic fracturing in horizontal wells has proven to be the most effective method of production stimulation at the Priobskoye field with hard-to-recover oil reserves. At that, evaluation of the efficiency of the multistage hydraulic fracturing and of the inflow from each formation fracture currently remains a complex and vital problem for horizontal wells. Several monitoring methods were practiced at the Priobskoye field in order to select the optimum one from the viewpoint of easy application and the accuracy of the information obtained concerning the productivity of each hydraulic fracture.

The following conventional and contemporary methods of multi-fractured well monitoring have been considered for practising at the field in Western Siberia: conventional production logging tools using coil tubing and distributed temperature survey monitoring technology (DTS) using fiber optic cable, marked proppant and intelligent inflow tracers.
Mechanistic Modeling of Foam Flow Through Porous Media in the Presence of Oil: Review of Foam-Oil Interactions and an Improved Bubble Population-Balance Model
Authors: Ma Kun , Mateen Khalid , Ren Guangwei , Luo Haishan , Bourdarot Gilles , Morel Danielle
Published: October 2018

Modeling foam flow through porous media in the presence of oil is essential for various foam-assisted enhanced oil recovery (EOR) processes. We performed an in-depth literature review of foam-oil interactions and related foam modeling techniques, and demonstrated the feasibility of an improved bubble population-balance model in this paper.

We reviewed both theoretical and experimental aspects of foam-oil interactions and identified the key parameters that control the stability of foam lamellae with oil in porous media. Upon reviewing existing modeling methods for foam flow in the presence of oil, we proposed a unified population-balance model that can simulate foam flow both with and without oil in standard finite-difference reservoir simulators. Steady-state foam apparent viscosity as a function of foam quality was used to evaluate the model performance and sensitivity at various oil saturations and fluid velocities.

Our literature review suggests that, among various potential foam-oil interaction mechanisms, the pseudo-emulsion-film (gas/aqueous/oil asymmetric film) stability has a major impact on the foam-film stability when oil is present. Based on the pseudo-emulsion-film mechanism, we therefore developed a new foam-coalescence function in the population-balance model using the gas-water capillary pressure (Pcgw) in oil-free cases and the pseudo-emulsion capillary pressure (Pcpf) when oil was present. The respective critical values Pcgw * and Pcpf * can be estimated through disjoining pressure measurements. A smooth transition, from no foam destabilization at zero or substantially low oil saturations to no foam beyond a critical oil saturation, was considered for this purpose. The new model was able to handle the extent of the detrimental effect of oil on foam with one adjustable parameter k-2.

This work consolidated various findings of foam-oil interactions based on pseudo-emulsion films in the past through a comprehensive literature survey. We have developed a unified model to simulate foam flow in porous media with and without oil using the mechanistic population-balance approach for the first time. This model can therefore be used in foam EOR simulations both in the oil-bearing zones as well as zones with no oil or residual oil present.
Challenges in the Development of Saline Terrigenous Reservoirs of Eastern Siberia Field
Authors: Levanov Andrey , Ignatyev Nikita , Ostyakov Evgeniy , Vinogradov Igor , Busuek Elena , Cherepkova Anna , Yaschenko Sergey , Schetinina Natalya , Semenov Aleksey , Nesterov Pavel , Musin Roman , Dolgov Igor , Komarov Andrey , Chirgun Aleksandr
Published: October 2018

At present, Russia's oil production in a number of large Eastern Siberia fields (Verkhnechonskoye, Talakanskoye, Yaraktinskoye) has reached or approached its maximum designed levels, therefore, the fields have progressed to the second stage of development or to the beginning of the third stage experiencing production declines. Thus, these fields can be categorized as brownfields.

At the Verkhnechonskoye oil and gas condensate field, for the first time in the history of domestic oil and gas production the geologists came across a highly mineralized productive cross-section with the pore space partially or completely filled with salt. This determined the distinctive development features of the main target - the Verkhnechonsky horizon (Vch) (99.8% of the field's production).

A distinctive feature of this paper is the description of the approaches to the development of the Verkhnechonsky horizon associated scaling formation and control using a wide range of geological and geophysical tools.

The value of the work lies in the summary of lessons learned when managing reserves production and well operation processes at a large Eastern Siberia field, the development of which is complicated by the presence of salts in the pore space, which was the starting point of accumulating the knowledge on salt reservoir development. The experience based on a range of approaches and technical solutions can be applied to similar Eastern Siberia reservoirs with similar geological and physical characteristics.
Characterization of ADOTS Carbogenic Nanoparticle Tracers Before and After Reservoir Injection
Authors: Alqahtani Hassan , Hussain Mohammad Kamal , ALShateeb Hussain , Ellis Erika
Published: October 2018

The main challenge facing any nanoparticle-based reservoir agent stability and transport through hydrocarbon reservoirs under harsh conditions (typically up to 220 kPPM TDS, ~10% divalent cations, 100°C temperature and 3200 psi pressure) without loss or degradation. Therefore, appropriate understanding of the physical and chemical character of candidate systems, e.g. ADOTS fluorescent nano-tracers, is highly needed. Results reported here show that the pre-injected ADOTS diluted in DI water, HPLC water and seawater have exactly the same 450 nm peak under the fluorescence spectrophotometry. However, both pre-injected and filtered post-injected ADOTS samples have also exactly the same peak position. Raman measurements are identical confirming the presence of ADOTS in samples before and after the injection. This improved physical and chemical understanding supports future development of both coatings and novel cores on the ADots platform.
Big Problem-Small Solution: Nanotechnology-Based Sealing Fluid
Authors: Todd Larry , Cleveland Matthew , Docherty Kevin , Reid James , Cowan Kenneth , Yohe Christopher
Published: October 2018

A nanotechnology-based sealing fluid was developed to solve compromised integrity in pathways too small, smaller than 120 μm, for conventional methods such as cement squeezes. Well integrity and environmental stewardship are at the forefront of our industry's relation with the public as oil and gas fields continue to encroach toward urban centers and the places we live and work. This push towards improved well integrity and a growing number of mature wells requires new and novel technologies and materials to achieve our goals.

The nanotechnology-based sealing fluid is capable of penetrating small gaps, as small as 20 μm, and seals through a reaction from either set cement or brine in the leak path. Candidate wells were selected based on very low injectivity rates that conventional remediation techniques could not tackle. Six candidate wells were selected, and of them, two were selected to cure a leaking gas microannulus causing sustained casing pressure and four were selected to cure a pinhole leak in the casing to pass the Texas Railroad Commission H-5 pressure test. For the pinhole leak, the nanosealant was placed across the leak point, and pressure was applied at surface continually until leakoff was minimized. The leaking gas microannulus was squeezed from surface until the leakoff was eliminated.

The nanotechnology-based sealing fluid was successful in each case. For the leaking microannulus wells, hesitation squeeze schedules were applied, and both leaks were sealed with a projected penetration greater than 500 ft. These wells were then tested with light detection and ranging (LIDAR) to ensure no gas leaks were occurring at surface after the treatment. For the candidates selected with casing leaks, all passed the regulatory Texas Railroad Commission H-5 pressure test and were put back into service. Three of the wells resulted in a final pressure drop of 0 psi/min based on the hesitation squeezes, and the other one well resulted in a pressure bleedoff reduction more than 25 times the original bleedoff rate.

The activation mechanism based on contact with annular materials is a significant breakthrough in squeeze operations because it removes all complexity from the fluid design, which historically required extensive laboratory testing. It also removes time-based boundaries on placement, and ultimately, it eliminates or reduces the drillout time compared to conventional or resin applications. Conventional remedial placement techniques can be used with the sealant, thus further simplifying the job execution. This combination of simplified execution techniques and the lack of necessary laboratory testing and well condition input allows for a quick fit-for-purpose implementation as problems arise, which saves both time and money.
Pore-Scale Imaging to Investigate Wettability and Recovery Mechanism for Surfactant/Polymer Flooding
Authors: Ahmed M. Elmuzafar , Sultan Abdullah S. , AlSofi Abdulkareem , Al-Hashim Hasan S. , Hussaini Syed R.
Published: October 2018

Surfactant-polymer (SP) flooding is a promising chemical enhanced oil recovery method in carbonates with high salinity brines especially where an existing waterflooding infrastructure is in place. SP flooding improves both the microscopic and macroscopic sweep efficiencies. The polymer viscosifies the injection water to control mobility, while the surfactant reduces the oil-water interfacial tension, and possibly alter wettability, to mobilize trapped oil. In this work, we investigate SP flooding recovery mechanisms in carbonates at the pore-scale.

Two polymers were used in this work: a Thermo-Viscosifying Polymer (TVP) and an Acrylamido tertiary butyl sulfonate (ATBS) with an acrylamide (AM) copolymer. Surfactants utilized were different grades of an amphoteric carboxybetaine. A set of four coreflooding experiments were performed at 90°C with a high-salinity injection brine (57,000 ppm). The first two corefloods investigated the independent performance of the chemicals (i.e. polymer flooding and surfactant flooding). The remaining two investigated the combined effects of SP flooding. The effects of different aging times were studied, too. Furthermore, micro-CT imaging were conducted at different steps both before and after flooding to evaluate saturation distributions and the chemicals effects on recovery. The images were also processed to segment the different phases which allows further evaluation of recovery mechanisms at the pore-scale.

Based on fluid occupancy maps, samples aged for one week exhibited strong water-wetness while samples aged for two weeks exhibited moderate water-wetness. In samples aged for one week, the final fluid occupancy was (i.e. remaining oil existed as) buckets of oil surrounded by water. While in samples aged for two weeks, the remaining oil was weekly attached to the surface of the pores. In terms of the recovery performance of the independent processes, the polymer flood showed better recovery than the surfactant flood. This supports the conclusion that in water-wet media the effect of surfactant alone is not significant if not coupled with mobility-control. In general, this work also demonstrates the utility of Micro-CT scanning in providing better understanding of recovery mechanisms at the pore-scale. With more accurate segmentation of the different phases, it can also provide a mean for in-situ contact angle measurements.