DOI: 10.24412/2076-6785-2023-1-76-80
Abstract
The article considers the peculiarities of well killing in the conditions of terrigenous high-permeability reservoirs, typical for Eastern Siberia in the example of formation VCh 1–2 of Verkhnechonskoye oil-gas-condensate field are described. Studies of the instantaneous filtration composition for the purpose of controlling absorptions during well killing and field tests of the technology were carried out. The results testify to promising application of compositions with spurt lossfor killing wells in complicated conditions, exploiting terrigenous reservoirs of Eastern Siberia.
Materials and methods
Analysis of the application of killing technologies with bottom-hole zone blocking in the Verkhnechonsk oil and gas condensate field. Substantiation of a choice of the new technology on the basis of the world experience. Physico-chemical and filtration studies of the new composition in the conditions of the considered object. Analysis of the results of field testing of the considered technology on the well.
Keywords
well killing, abnormally low reservoir pressure, low temperature, fluid loss, blocking compounds, composition with spurt loss, Eastern Siberia
DOI: 10.24412/2076-6785-2023-1-72-75
Abstract
The migration of residual oil is partial flow of reserves that was displaced into zones with no production wells or from unswept zones after well shutting. This process is facilitated by favorable geological conditions, such as high continuity, permeability and connectivity of the formation, and the presence of anticlinal dome. Based on the results of drilled transit wells, the oil migration effect was confirmed, recommendations
for further development of shallow marine sandstone of one of the fields in Western Siberia were given.
Materials and methods
This paper presents an algorithm for oil field secondary development at a late stage of development, is proposed, which includes
the integration of research: selection and analysis of a new core, revision of the reservoir properties of rocks, conducting gyroscopic studies on old wells, analyzing the saturation of transit wells, rebuilding a hydrodynamic model with new data.
Keywords
oil migration, the last stage of oil field development, the development
of residual oil reserves
DOI: 10.24412/2076-6785-2023-1-66-69
Abstract
The article presents the example of searching for an analogue, the adaptation of the hydrodynamic model of the target reservoir on the history of the selected analogue development and searching optimal development option by carrying out multivariate calculations.
Materials and methods
Characteristics of displacement of an analogue reservoir object.
Using an analogue object to verify the hydrodynamic model of a new reservoir object.
Keywords
hydrodynamic model, development system, multivariate calculations, geological-physical characteristics, analogue, oil and gas condensate reservoir
DOI: 10.24412/2076-6785-2023-1-61-65
Àbstract
The article presents the experience of calculating the potential for reducing water production, developed as part of a project to reduce the cost of lifting well products. The idea of the work is to calculate the probability and volume of water production exceeding the level of current production of oil reserves. It is assumed that the positive difference between the actual and theoretical water cut calculated from the production of oil reserves in the well determines the potential for reducing water production and is associated with extraction from an inappropriate interval, or with a violation of the integrity of the well structure, or with water breakthroughs through highly permeable layers, or cone formation. The probability of extraction of “foreign water” is estimated by the degree of compliance with the signs of abnormal flooding.
Materials and methods
The article describes a methodology for analytical search of candidate wells for repair and insulation works based on the developed criteria. Geological and field data of monthly operational reports, data of technological modes, data on perforation intervals and information of design. The results of the calculations allow us to assess the economic efficiency of potential measures to reduce water production.
Keywords
squeeze job, water shut-off operations, casing patch operations, “foreign water”, productivity coefficient, water cut, premature watering
DOI: 10.24412/2076-6785-2023-1-56-60
Abstract
This article is devoted to the study of geomechanic and porosity clays properties influence on the processes of pressure redistribution and fluid filtration in the well drainage area, and as a result, on well productivity. Comparison of the calculation results showed a significant effect of clay interlayers in the reservoir section on the performance and productivity of the well.
Materials and methods
The study was carried out by creating synthetic hydrodynamic models with a different number of clay interlayers in the section of the productive formation, while maintaining the volume ratio between sandstone and clay in the ratio of 50:50. The Arps and Fetkovich methods were used to analyze decline curve anaysis production and calculate predicted values of cumulative production in the area of well drainage, assess and compare the rate of change in fluid production in wells.
Keywords
clay rocks, pore space compressibility, reservoir properties, reservoir modeling, decline curve analysis, Arps method, Fetkovich method
DOI: 10.24412/2076-6785-2023-1-46-53
Annotation
The paper considers an approach to the development of deposits of tight oil, characterized by a complex geological structure, ultra-low permeability (less than 1 mD) and saturation differentiation. The use of standard approaches and development technologies for such complex reservoirs makes it difficult to obtain high efficiency of oil recovery. In order to choose the optimal development technology, the applicability of gas methods
for enhanced oil recovery was evaluated using analytical techniques and calculations based on a compositional flow model.
Materials and Methods
The paper gives the numerical estimations of the Minimum Miscibility Pressure (MMP) of oil and various gas agents (APG, CO2, methane) made via correlations and EOS matched to standard studies
of downhole samples. A preliminary feasibility study of various development options for the reservoir in question (water and gas injection) was performed on a sector composite flow simulation model.
Keywords
tight oil, low permeability, hydraulic fracturing, pilot works, technology testing, gas methods of enhanced oil recovery
DOI: 10.24412/2076-6785-2023-1-41-45
Abstract
The work is devoted to the study of the effect of the hysteresis of relative permeability on the numerical evaluation of the effectiveness of water-alternating-gas (WAG) effects on models of various scales: a one-dimensional model of the core column (evaluation of the effect of the hysteresis of the core column on the quality of model adaptation to the results of flow experiments on core columns in the absence of gravity), a two-dimensional synthetic model of two wells (evaluation of the effect of hysteresis relative permeability for the amount of additional oil production in the presence of gravity), three-dimensional full-scale model of the deposit (evaluation of the effect of the hysteresis relative permeability on the efficiency of the WAG).
Materials and methods
Materials: results of core experiments on oil displacement by gas and water fringes. Methods: numerical simulation using the Eclipse 300 hydrodynamic simulator.
Keywords
hysteresis relative permeability, oil and gas miscibility, efficiently of WAG
DOI: 10.24412/2076-6785-2023-1-36-40
Abstract
Currently, in the Eastern Siberia oil fields, in the conditions of infrastructural restrictions, the simultaneously produced gas utilization problem, as well as breakthrough of gas caps extracted during the oil rims development, is acute. One of the ways to limit gas production during the oil rims development is the autonomous monitoring devices (AICD) usage at the completion of the well. At the Srednebotuobinskoye field, located in Eastern Siberia, successful work was carried out on the autonomous inflow control devices usage and full-scale replication began as part of the thin oil rim development of the Botuobin horizon.
Materials and methods
As part of the pilot project, 4 wells with AICD were implemented. Based on the results, full-scale replication has begun. For the completion design, a tool has been developed for arranging the amount of AICD
in each segment of the well, depending on the geological and technological conditions.
Keywords
autonomous inflow control device, AICD, cone formation, gas breakthrough, gas factor, accumulated oil production, Eastern Siberia, Botuobinsky horizon
DOI: 10.24412/2076-6785-2022-3-48-52
Abstract
An integrated approach has been formed to justify the designs of planned gas wells, taking into account the accumulated experience in the formation of a strategy and technology for the development of the turonian stage. A decision matrix has been created for choosing the optimal well completion method depending on saturation (pure gas and water gas zones) and reservoir properties (in particular Kh). An express assessment has been developed for choosing a well completion method for poorly explored and undrilled zones.
Materials and methods
By forming and performing many calculations on sector hydrodynamic models depending on saturation (pure gas and water gas zones) and reservoir properties (in particular Kh), individual well designs, the number of stages of hydraulic fracturing and tonnage proppant are recommended for each of the typical zones of the productive formation
according to the created decision matrix.
Keywords
turonian stage, reservoir saturation zones, reservoir conduction zones, sector hydrodynamic models, well completion methods
DOI: 10.24412/2076-6785-2022-2-60-64
Abstract
The increase in the share of hard-to-recover reserves makes it relevant to introduce physico-chemical methods of increasing oil recovery. Polymer flooding is a promising method. One of the factors influencing the success of this technology is the retention (adsorption) of the polymer in a porous medium. At a high value of adsorption, there is an intense loss of viscosity of the injected composition, colmatation of the downhole region of the formation is possible. It is necessary to select compositions characterized by acceptable retention values in the reservoir of a particular deposit. The article provides an example of the assessment of adsorption, including the influence of various factors on its magnitude.
Materials and methods
Laboratory tests were carried out according to the guidelines of the Institute “Hyprovostokneft” [14] and of the American Petroleum Institute [15]. All stages of preparation of reservoir models and fluids for research are based on OST 39-195-86 “Oil. Method for determining the oil displacement coefficient by water in laboratory conditions”.
Keywords
adsorption, concentration, polymer, temperature
DOI: 10.24412/2076-6785-2021-5-46-51
Abstract
In this work, we studied the effect of bimetallic catalysts formed in situ from mixtures of oil-soluble iron and cobalt precursors in the process of aquathermolysis of heavy oil from the Ashalchinsky field. Based on the results of determining the group composition (SARA analysis) and viscosity-temperature characteristics, an improvement in the composition and an increase in the mobility of oil under the action of steam and a bimetallic catalyst is shown. It was found that the catalyst intensifies the destructive processes of resinous compounds, provokes the enrichment of the destruction products of the latter in the saturated and aromatic fractions with high molecular weight n-alkanes and polycyclic hydrocarbons, respectively. It was revealed that the proposed catalyst of the optimal composition is a mixture of individual and mixed oxides and sulfides of iron and cobalt (ferrospinels). Catalyst can be used at the Ashalchinsky field of heavy oil in conditions close to reservoir conditions (200 °C, 10 bar), as a reagent providing an increase in the degree of oil recovery.
Materials and methods
Heavy oil of the Ashalchinsky field of the Republic of Tatarstan, SARAanalysis, viscometry, gas chromatography-mass spectrometry (GC-MS), catalyst active form, XRD.
Keywords
heavy oil, steam treatment, bimetallic catalyst, oil-soluble precursors, catalyst active form, in-situ upgrading, EOR
DOI: 10.24412/2076-6785-2021-5-42-44
Abstract
This article evaluates the study of the direction of spread of natural fracturing and predominant direction of propagation of cavernousness of the carbonate reservoir of the Podol-Kashiro-Vereiskian object of the Elnikovskoye oil field. The studies are based on the analysis of information on the sampled core, tracer studies, the FMI method and the mutual influence of production/injection wells. The study identified the main directions of natural fractures and vugginess. These parameters must be taken for well coverage, in particular, adjusting the location of production/injection wells in order to prevent anticipatory water invasion, as well as when selecting candidates for geological and technical measures to increase the
final oil recovery factor.
Materials and methods
Based on the analysis of practical material on optimizing the conditions of the fields being developed in the territory of the Udmurt Republic.
Keywords
natural fractures, natural vugginess, development, oil field, carbonate reservoir rock, geological and technical actions, interference of wells
DOI: 10.24412/2076-6785-2021-4-46-52
Abstract
Nonionic surfactants provide benefits of possibility of large-scale production for oil industry demands. However, the laboratory and field tests
show their inferiority to anionic surfactants due to propensity for salting out when the reservoir temperature is higher than the cloud point of
the repressuring solution containing the nonionic surfactant. This paper describes the results of a field test of water solutions of alkylphenol
ethoxylates from different manufacturers, both with and without polyacrylamide, compared to the previous field tests of these reagents.
The innovative technologies for use of nonionic surfactants are based on their thermal salting out from the water solution and on the polyacrylamide
complex formation possessing high selectivity when moving in the reservoir, i.e. poor filtration into the watered and good filtration into the oilsaturated
areas.
Materials and methods
Materials: data on the field test of nonionic surfactants as a reagent
for improving reservoir oil recovery in Western Siberia and Urals-Volga
regions.
Methods: analysis of the results obtained when testing variety of technologies based on using aqueous nonionic surfactant solutions in
the oil fields of Western Siberia and Urals-Volga regions.
Keywords
nonionic surfactant, improving reservoir recovery, field tests
DOI: 10.24412/2076-6785-2021-3-34-40
Abstract
The process of raising the gas-water contact (GWC) is inevitable during development of the reservoir. This leads to flodding of wells and reducing of daily gas production. Horizontal sidetracks and new horizontal drilling allows to maintain production at the required level. Mostly, the direction of the horizontal section of the well determines its efficiency. In difficult geological conditions, a detailed analysis of seismic data in the drilling area allows to reduce drilling risks and achieve planned starting rates. Accounting of seismic data in geological models is often limited by a low correlation coefficient between reservoir properties obtained from wells and seismic attributes. Simulation models use seismic data based on the assumptions made by the geological engineers.
Materials and methods
In this paper authors uses a iterative approach to geological modeling: implementations include in-depth analysis of seismic data and well performance dynamics. Modern software modules were used to automatically check the compliance of the geological implementation with the development history, as well as to assess the uncertainties. High correlation coefficients between well water cut and seismic attributes obtained. Authors developed a method for determining the presence of shale bodies and “confluence windows” of a massive gas reservoir with water-saturated volumes.
Keywords
geological modeling, simulation run, Pokurskaya suite, gas reservoir, cenomanian, horizontal wells, attribute analysis
DOI: 10.24412/2076-6785-2021-3-29-32
Abstract
The article describes the selection approach for the efficient development method of the vereiskian formation of the Chutyr field. To optimize the method, the filtration model of the vereiskian and bashkirian formations was prepared and historically matched. Based on multialternative calculations, the practical field development method was determined.
Materials and methods
Based on the analysis of practical material, the testing of the method of foam acid exposure in the conditions of developed fields in the territory of the Udmurt Republic.
Keywords
efficient system, development method, gas and oil field, filtration model, fluid flow model, multialternative calculations, modelling
DOI: 10.24412/2076-6785-2021-2-57-60
Abstract
The paper is devoted to the accounting of nonlinear filtration in hydrodynamic modeling of the oil displacement process. The authors analyzed and identified the main factors that are the reasons for the deviation from the linear filtration law. The work considered a method of mathematical modeling of non-newtonian oil properties. In the process of filtration modeling, an algorithm for converting the geological-physical characteristics (GPC) of oil fields into coefficients used by a hydrodynamic simulator to take into account nonlinear filtration was created and tested. Thus, a hydrodynamic model (HDM) of an oil field has been built, capable of taking into account the deviation from the linear Darcy's law and quantify the impact of non-newtonian oil properties on the development process.
Materials and methods
To calculate the limit dynamic shear stress (LDSS) of degassed (1) and gas-saturated oil (2), a technique was used based on studies of the properties of oils from the Volga-Ural province [1].
Keywords
hydrodynamic modeling, nonlinear filtering, deviation from linear Darcy's low, non-newtonian properties of oil, gradient of the dynamic structure destruction, gradient of the limit structure destruction, nine point development system of oil, residuals reserves, geological and physical characteristics
DOI: 10.24412/2076-6785-2021-2-48-52
Abstract
The article is devoted to the comparison of the capabilities of two analytical models describing the operation of oil fields, namely CRM and stochastic-analytical model (SAM). These tools for controlling and regulating the technological mode of withdrawal and injection neutralize the disadvantages expressed in the uncertainty of the adaptation of hydrodynamic models (HDM) and the distribution of reservoir properties (PRP) in the zones between wells, and also act as "assistants" in setting up the hydrodynamic model, conducting analysis and monitoring RPM systems. The inverse problem of underground hydromechanics is solved in the form of CAM (“autohydro-self-monitoring”), while CRM is represented by an equation based on material balance.
Materials and methods
Analytical solution of the problems of analysis and optimization of the waterflooding system, the ability to assess the filtration properties of the reservoir in the vicinity of wells and between pairs of wells of candidates for geological and technical measures.
Keywords
Hydrodynamic modeling, stochastic-analytical models, analytical models, reservoir pressure maintenance system
DOI 10.24412/2076-6785-2021-2-41-46
Abstract
The risk assessment of sand production in the wells was carried out based on the results of a core study and hydro-geomechanical modeling of the formation. The paper presents and implements an algorithm for calculating the project indicators for the development of the Kharampurskoye oil and gas condensate field using combined hydro-geomechanical modeling, which makes it possible to take into account changes in reservoir properties and elastic-strength properties in deformed and bottomhole formation zones. Based on the results of the calculations, the risk of sand production and the collapse of the bottomhole formation zone was predicted throughout the development of the field. Recommendations were given to minimize the risks of sand production.
Materials and methods
Based on the results of laboratory studies, an assessment of the change in the elastic-strength properties of core samples when saturated with various fluids (natural saturation and water) was carried out. Based on the results of core testing on thick-walled cylinders, an estimate of the permissible depression was obtained. 3D/4D coupled hydrogeomechanical modeling was performed to assess the geomechanical effects associated with the change in the elastic-strength properties of rocks from saturation, which allows taking into account the effect of rock destruction on permeability.
Keywords
laboratory core studies, elastic-strength properties, different saturation,
depression assessment, associated hydro-geomechanical modelingñ
DOI: 10.24412/2076-6785-2021-2-33-36
Abstract
The main element of the well design, which determines the life of the wells, is the production strings (PS). Premature failure of the production strings requires significant expenses for its restoration, and the unprofitability of its restoration by repair methods leads to unjustified expenses for abandoning the well and drilling a duplicate well. The article briefly describes the impact of negative factors on the integrity of the PSs of the wells and outlines the possibilities to reduce their impact. Specific recommendations are offered.
Materials and methods
Actual data of well survey by geophysical, hydrodynamic methods, analytical methods of generalization of field data, engineering calculations of technological processes.
Keywords
production strings of a well, hermos-baric action, steam injection wells, corrosion effects, downhole protective composition, repair and insulation works, pressure testing
DOI: 10.24412/2076-6785-2021-1-45-48
Abstract
The issues of stimulating the inflow from carbonate reservoirs, as well as increasing the oil recovery factor are among the most relevant. With classical multiple acid treatments, hydrochloric acid penetrates into the same high-permeability intervals of the bottomhole formation zone (BHZ), and the coverage of the formation by impact decreases. Thus, one of the most important tasks of oil production is to increase the efficiency of acidizing wells. The problem becomes most urgent due to the fact that at present most of the large fields in Russia are at a late stage of development, the work of the deposit is carried out at reduced reservoir pressures, and the reservoir itself is heterogeneous. The article deals with the use of foam-acid treatment of the formation to increase oil production at the fields of the Volga-Ural region.
Materials and methods
Based on the analysis of practical material, the testing of the method of foam acid exposure in the conditions of developed fields in the territory of the Udmurt Republic.
Keywords
acid treatment, foam acid, acid deviation, increased efficiency of repeated BHT, carbonate reservoir