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Date submitted2022-10-04
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Date accepted2024-03-05
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Date published2024-08-26
Localization and involvement in development of residual recoverable reserves of a multilayer oil field
During waterflooding of a multilayer oil field there is a constant deterioration of the structure and composition of residual reserves due to geological and technological reasons. The largest share of residual reserves is localized in pillars, which arise from uneven development of the production facility and are undrained or poorly drained zones. The results of a quantitative assessment of the distribution of residual oil reserves in the Middle and Upper Devonian deposits of the Romashkinskoe oil field of the Republic of Tatarstan are presented. A retrospective method is proposed to identify reserves by analyzing and summarizing historical exploration data and the long history of reservoir development, and a calculation algorithm is proposed to quantify them. It has been established that residual oil reserves are localized in rows of dividing and injection wells, as well as in the central rows of producing wells in a three-line drive, in abandoned and piezometric wells, in the areas adjacent to the zones of reservoir confluence, pinch-out, oil-bearing contours, distribution of reservoirs with deteriorated porosity and permeability properties. Depending on geological conditions, algorithms for selecting geological and technical measures to include localized reserves in development and forecasting production profiles were proposed. According to the proposed method, residual recoverable reserves were identified and a number of wells were recommended for experimental works on their additional recovery: in well 16 (hereinafter in the text, conventional well numbers are used) after isolation of overlying high-water-cut formations, the additional perforation was carried out and oil flow was obtained. Additional perforation in well 6 resulted in oil recovery during development as well. Thus, the developed approaches to identifying residual recoverable reserves and patterns of their spatial distribution can be recommended in other multilayer oil fields with a long history of development.
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Date submitted2024-04-08
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Date accepted2024-06-13
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Date published2024-12-25
Analysing the problems of reproducing the mineral resource base of scarce strategic minerals
The results of studying the scarcity of strategic minerals in the Russian Federation are presented, domestic consumption of which is largely provided by forced imports and/or stored reserves. Relevance of the work is due to aggravation of the geopolitical situation and a growing necessity to meet the demand of national economy for raw materials from own sources. Analysis of the state of mineral resource base of scarce minerals in the Russian Federation was accomplished, problems were identified and prospects for its development were outlined taking into account the domestic demand for scarce minerals, their application areas and the main consumers. Reducing the deficit through the import of foreign raw materials and the development of foreign deposits does not ensure the reproduction of the domestic mineral resource base, independence of the country from imported raw materials as well as additional competitive advantages, economic stability and security. It was ascertained that a major factor holding back the development of the mineral resource base is insufficient implementation of new technological solutions for the use of low-quality ore. Improving the technologies in the industry is relevant for all types of scarce minerals to solve the problem of reproducing their resource base. Taking into account the prospects for the development of the resource base for the minerals under consideration (manganese, uranium, chromium, fluorspar, zirconium, titanium, graphite) requires a set of legal and economic measures aimed at increasing the investment attractiveness of geological exploration for subsoil users at their own expense without attracting public funding. The proposed measures, taking into account the analysis of positive experience of foreign countries, include the development of junior businesses with expansion of the “declarative” principle, the venture capital market, various tax incentives, preferential loans as well as conditions for the development of infrastructure in remote regions. The proposed solution to the problem of scarcity of strategic minerals will make it possible in future to present measures to eliminate the scarcity of certain types of strategic minerals taking into account their specificity.
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Date submitted2023-11-27
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Date accepted2023-12-27
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Date published2024-02-29
Physico-chemical aspects and carbon footprint of hydrogen production from water and hydrocarbons
Physico-chemical aspects determine the efficiency and competitiveness of hydrogen production technologies. The indicator of water consumption is especially relevant, since water is one of the main sources of hydrogen in almost all methods of its production. The article analyzes comparative water consumption indicators for various technologies based on published research and actual data from production plants. The volume of water consumption depends on the quality of the source water, which should be taken into account when implementing hydrogen projects in order to minimize the negative impact on the environment. Based on the operating industrial plant, the material balance of hydrogen production by steam reforming was demonstrated, which made it possible to determine the proportion of hydrogen (48.88 %) obtained from water. Currently, the carbon footprint indicator is becoming more important, reflecting greenhouse gas emissions throughout the production chain. According to the results of the total greenhouse gas emissions assessment for hydrogen production by steam reforming (about 10.03 kg CO2-eq/kg H2), the carbon footprint of hydrogen from water (4.2-4.5 kg CO2-eq/kg H2) and hydrogen from methane (15.4-15.7 kg CO2-eq/kg H2) has been determined. Consequently, almost half of the hydrogen produced by steam reforming is produced from water, corresponds to the indicators of “low-carbon” hydrogen and can be considered as “renewable” hydrogen. To make management decisions, an objective assessment in terms of energy and water costs is necessary based on a system analysis by the development of hydrogen energy and the growth of global hydrogen production. The impact of these indicators on the water cycle and global water resources will increase.
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Date submitted2023-08-02
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Date accepted2023-12-27
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Date published2024-04-25
Justification of the approaches to improve management strategy of the mining system based on the analysis of data on the mining of complex structural rock blocks
Long-term activity of mining enterprises causes the necessity to substantiate the strategies of management of the mining and technical system functioning in terms of improvement of ore quality control, which is determined by its change in the course of field development due to the priority development of the main reserves and, as a consequence, forced transition to the mining of complex structural rock blocks with a decrease in the recovery percentage, which is typical in case the ore component meets the requirements of the feasibility study in terms of grade at substandard capacity. In this case, it is possible to identify the recovery percentage and the potential for its increase by analyzing the long-term activity of the mining and industrial enterprise, namely, by analyzing the data of mining complex structural rock blocks with the subsequent establishment of the relationship between the primary data on mining and geological conditions and information on the quality of the mineral obtained from the technological equipment. Therefore, the purpose of the research was to substantiate the necessity of improving the management strategy of the mining-technical system functioning, which consists in the fact that on the basis of analyzing the mining data of complex structural rock blocks it is possible to determine the ore mass losses and their quantity and to lay the basis for the development of decisions on its extraction. For this purpose, the collected data on the mining of complex structural rock blocks, accounting the geological and industrial type of extracted ores, were considered in modeling the conditions and studying the parameters of technological processes, the implementation of which provides additional products. It was revealed that the ore mass from substandard thickness layers is delivered to the dumps, and ore mass losses have been estimated at 25-40 % per year. It is proved that determination of ore mass losses based on the analysis of data on mining of complex structural rock blocks, as well as timely solution of this issue can significantly increase the production efficiency of mining and technical system. Taking into account for the results obtained, the options for optimizing the production of the mining and engineering system were proposed.
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Date submitted2021-02-09
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Date accepted2023-09-20
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Date published2024-02-29
Analysis of experience in the use of preformed particle polymer gels in the development of high-water-cut production facilities in low-temperature oil reservoirs
- Authors:
- Sergei V. Galkin
- Yuliya A. Rozhkova
Foreign practice of oil production in high-water-cut conditions suggests using the technology of injection of preformed particle gel (PPG) suspension into injection wells. After swelling, the polymer particles become elastic and are able to penetrate through highly permeable watered intervals into the remote reservoir zone, forming a polymer “plug”. Thus far, the domestic experience of application of this technology boiled down to testing foreign compounds. We have looked into the possibilities of PPG technology application in geological and technological conditions of high-water-cut fields of Perm Krai. The paper proposes PPG reagents effective in low-temperature reservoirs (20-35 °С) and at relatively high salinity of formation water (more than 200 g/l). The world experience of PPG technology application was analyzed to identify the principal scheme of reagent injection, to establish variants of sequence of injection of PPG particles of different sizes, as well as the possibility of regulating the morphological characteristics of polymer gel particles during synthesis depending on the porosity and permeability of the reservoir. A prerequisite for the technology is the ability to remove PPG particles after treatment from the bottom-hole zone of the formation; for this purpose, tests were carried out on a breaker compound based on sodium persulfate with synergizing additives. PPG technology is effective in reservoirs with high permeability heterogeneity. Two types of high-water-cut production facilities potentially promising for PPG realization have been identified for oil fields of Perm Krai. The first type includes carbonate Tournaisian-Famennian reservoirs with pronounced macrofracturing, in which the PPGs are used for colmatation of flushed large fractures. The second type is terrigenous Visean deposits with increased oil viscosity from 5 to 100 mPa∙s and high permeability of reservoirs (> 0.5 μm2). For both types of reservoirs, areas have been selected that are promising for the implementation of PPG technology.
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Date submitted2023-02-07
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Date accepted2023-06-20
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Date published2024-02-29
Origin of carbonate-silicate rocks of the Porya Guba (the Lapland-Kolvitsa Granulite Belt) revealed by stable isotope analysis (δ18O, δ13C)
- Authors:
- Dmitrii P. Krylov
- Ekaterina V. Klimova
Carbonate-silicate rocks of unclear origin have been observed in granulites of the Porya Guba of the Lapland-Kolvitsa Belt within the Fennoscandinavian Shield. The present work aims to reconstruct possible protoliths and conditions of metamorphic transformation of these rocks based on oxygen and carbon isotopic ratios combined with phase equilibria modeling. Isotope analysis and lithochemical reconstructions suggest that carbonate-silicate rocks of the Porya Guba represent metamorphosed sediments (possibly marls) with the isotopic composition corresponding to the Precambrian diagenetically transformed carbonates (δ18O ≈ 17.9 ‰, SMOW and δ13C ≈ –3.4 ‰, PDB). The chemical composition varies depending on the balance among the carbonate, clay, and clastic components. Significant changes of the isotopic composition during metamorphism are caused by decomposition reactions of primary carbonates (dolomite, siderite, and ankerite) producing CO2 followed by degassing. These reactions are accompanied by δ18O and δ13C decrease of calcite in isotopic equilibrium with CO2 down to 15 ‰ (SMOW) and –6 ‰ (PDB), respectively. The isotopic composition is buffered by local reactions within individual rock varieties, thus excluding any pronounced influence of magmatic and/or metasomatic processes.
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Date submitted2022-09-30
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Date accepted2023-04-03
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Date published2024-02-29
Optimization of the location of a multilateral well in a thin oil rim, complicated by the presence of an extensive gas cap
- Authors:
- Кirill О. Тomskii
- Mariya S. Ivanova
The specific share of the reserves of hard-to-recover hydrocarbon raw materials is steadily growing. The search for technologies to increase the hydrocarbon recovery factor is one of the most urgent tasks facing the oil and gas industry. One of the methods to expand the coverage of oil reserves and increase oil recovery is to use the technology of drilling multilateral wells with a fishbone trajectory. In the Russian Federation, the most branched well was drilled in the Republic of Sakha (Yakutia) at the Srednebotuobinskoye oil and gas condensate field. The main object of development is the Botuobinsky horizon (Bt reservoir). About 75 % of the geological reserves of the reservoir are concentrated in a thin oil rim with an average oil-saturated layer thickness of 10 m with an extensive gas cap. This circumstance is one of the main complicating factors in the development of the Srednebotuobinskoye oil and gas condensate field. For such complex wells, one of the most important design stages is to determine the optimal location of the fishbone well in an oil-saturated reservoir. The article shows the results of sector modeling in the conditions of the Srednebotuobinskoye field to determine the optimal location of multilateral wells using Tempest simulator.
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Date submitted2022-04-02
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Date accepted2022-11-28
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Date published2022-12-29
Improving the energy-efficiency of small-scale methanol production through the use of microturboexpander units
The issue of improving the energy-efficiency of container-based gas chemical plants for methanol production in field conditions is considered. The relevance of the direction is determined by the necessity for development of remote Arctic hydrocarbon fields. The object of research is energy-efficient conversion of waste gases energy and surplus thermal energy in small-scale system of methanol production using technology of synthesis gas generation by non-catalytic partial oxidation of natural gas. Approaches to the design and analysis of structural solutions for microturboexpander units are considered. A technique combining traditional approaches to the calculation of equipment and modeling by the finite element method in ANSYS is proposed. The developed methodology facilitates calculation of design parameters for microturboexpanders and allows taking into account peculiarities of working medium, thermobaric conditions and gas flow characteristics.
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Date submitted2022-05-03
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Date accepted2022-07-21
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Date published2022-11-03
Determination of rational steam consumption in steam-air mixture flotation of apatite-nepheline ores
Relevance of the study is determined by the decisions taken to increase the production volume of certain commercial products from mineral raw materials. The scale, impact and consequences of the projects on developing the resource-saving technologies for beneficiation of mineral raw materials are socially significant, and the economic growth of mining production complies with the sustainable development goals. The aim of the study is to develop the flotation circuit and mode that improve the technological performance of beneficiation of apatite-nepheline ores of the Khibiny Massif in the Kola Peninsula. The scientific idea of the work is to develop the flotation circuit, the movement of beneficiation products in which ensures a major increase in the content of the recovered component in the rougher flotation procedure with a simultaneous increase in dressability of the material. The above condition is met when mixing the feedstock with rough concentrate. Recovery of the valuable component from the resulting mixture is accomplished in a mode differing from the known ones in that the heat of steam condensation is used to increase water temperature in the interphase film between the particle and the bubble. For pulp aeration during flotation, a mixture of air and hot steam is used as the gas phase. A high recovery of the valuable component in ore flotation according to the developed circuit and mode is facilitated by increasing water temperature in wetting films due to the steam condensation heat. A high selectivity of flotation with a steam-air mixture can be explained using the concepts of a phonon component of disjoining pressure, the value and sign of which are associated with a difference in the dynamic structure of liquid in the wetting film and bulk liquid.
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Date submitted2021-12-19
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Date accepted2022-05-13
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Date published2022-07-13
Development of a pump-ejector system for SWAG injection into reservoir using associated petroleum gas from the annulus space of production wells
Implementation of SWAG technology by means of water-gas mixtures is a promising method of enhanced oil recovery. The use of associated petroleum gas as a gas component in the water-gas mixture allows to significantly reduce the amount of irrationally consumed gas and carbon footprint. Relevant task is to choose a simple, reliable and convenient equipment that can operate under rapidly changing operating conditions. Such equipment are pump-ejector systems. In order to create water-gas mixture it is proposed to use associated gas from the annulus space. This solution will reduce the pressure in the annulus space of the production well, prevent supply disruption and failure of well equipment. The paper presents a principal technological scheme of the pump-ejector system, taking into account the withdrawal of gas from the annulus space of several production wells. The layout of the proposed system enables more efficient implementation of the proposed technology, which expands the area of its application. Experimental investigations of pressure and energy characteristics of the ejector have been carried out. Analysis of the obtained data showed that it was possible to increase the value of maximum efficiency. The possibility of adapting the system in a wide range of changes in operating parameters has been established. Recommendations on selection of a booster pump depending on the values of working pressure and gas content are given.
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Date submitted2021-02-09
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Date accepted2021-07-27
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Date published2021-10-21
Development of an algorithm for determining the technological parameters of acid composition injection during treatment of the near-bottomhole zone, taking into account economic efficiency
Relevance of the research is due to the low proportion of successful hydrochloric acid treatments of near-bottomhole zones of carbonate reservoirs in the Perm region caused by insufficiently careful design and implementation of measures to stimulate oil production. Within the framework of this article, the development of a program is presented, which is based on an algorithm that allows determining the volume and rate of injection for an acid composition into a productive formation corresponding to the maximum economic efficiency during hydrochloric acid treatment. Essence of the proposed algorithm is to find the greatest profit from measures to increase oil recovery, depending on the cost of its implementation and income from additionally produced oil. Operation of the algorithm is carried out on the principle of enumerating the values of the volume and rate of injection for the acid composition and their fixation when the maximum difference between income and costs, corresponding to the given technological parameters of injection, is reached. The methodology is based on Dupuis's investigations on the filtration of fluids in the formation and the results of the experiments by Duckord and Lenormand on the study of changes in the additional filtration resistance in the near-well zone of the formation when it is treated with an acid composition. When analyzing and including these investigations into the algorithm, it is noted that the developed technique takes into account a large number of factors, including the lithological and mineralogical composition of rocks, technological parameters of the injection of a working agent and its properties, well design, filtration properties of the formation, properties of well products. The article provides an algorithm that can be implemented without difficulty using any programming language, for example, Pascal. Selection of the optimal values for the volume and rate of injection is presented in this paper, using the example of a production well at the Chaikinskoye oil field, located within the Perm region. Introduction of the developed algorithm into the practice of petroleum engineering will allow competent and effective approach to the design of hydrochloric acid treatments in carbonate reservoirs without a significant investment of time and additional funds.
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Date submitted2021-04-15
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Date accepted2021-07-27
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Date published2021-10-21
Analysis of the application and impact of carbon dioxide media on the corrosion state of oil and gas facilities
Products of several currently operated production facilities (Bovanenkovskoye, Urengoyskoye oil and gas condensate fields, etc.) contain an increased amount of corrosive CO 2 . Effect of CO 2 on the corrosion of steel infrastructure facilities is determined by the conditions of its use. Carbon dioxide has a potentially wide range of applications at oil and gas facilities for solving technological problems (during production, transportation, storage, etc.). Each of the aggregate states of CO 2 (gas, liquid and supercritical) is used and affects the corrosion state of oil and gas facilities. Article analyzes the results of simulation tests and evaluates the corrosion effect of CO 2 on typical steels (carbon, low-alloy and alloyed) used at field facilities. The main factors influencing the intensity of carbonic acid corrosion processes in the main conditions of hydrocarbon production with CO 2 , storage and its use for various technological purposes are revealed. Development of carbon dioxide corrosion is accompanied and characterized by the localization of corrosion and the formation of defects (pitting, pits, etc.). Even alloyed steels are not always resistant in the presence of moisture and increased partial pressures of CO 2 , especially in the presence of additional factors of corrosive influence (temperature, aggressive impurities in gas, etc.).
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Date submitted2020-05-13
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Date accepted2021-05-21
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Date published2021-09-20
Increasing the efficiency of technological preparation for the production of the manufacture components equipment for the mineral resource complex
An increase of components production for the equipment intended for oil and gas production is a key factor for analyzing existing technological processes and searching for new technological solutions to improve the efficiency of the production process and the quality of components. The article presents a simulation model designed to determine the rational technological processing parameters for the production of the “Centralizer shell” part. The basis for optimizing the working cycle of a production line is synchronization based on the principle of proportionality, which involves equalizing the duration of all technological operations with the rhythm of the production line. Synchronization of technological operations on the production line is carried out by choosing rational cutting parameters for each technological transition (cutting speed, feedrate, number of working passes). The “Centralizer shell” part is made of titanium alloy VT16, which has high strength, corrosion resistance and ductility. For the part under consideration, the permissible values of the cutting parameters were determined based on the calculation of the total processing error, as well as the frequency of replacement of the worn cutting tool. The simulation model described in the article made it possible to increase the efficiency of the production process due to the synchronization of technological operations and the search for rational technological parameters, as well as to improve the manufacturing quality of the “Centralizer shell” part by analyzing the processing error at various parameters of the technological process.
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Date submitted2020-06-16
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Date accepted2020-11-09
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Date published2020-12-29
Investigation of probabilistic models for forecasting the efficiency of proppant hydraulic fracturing technology
To solve the problems accompanying the development of forecasting methods, a probabilistic method of data analysis is proposed. Using a carbonate object as an example, the application of a probabilistic technique for predicting the effectiveness of proppant hydraulic fracturing (HF) technology is considered. Forecast of the increase in the oil production of wells was made using probabilistic analysis of geological and technological data in different periods of HF implementation. With the help of this method, the dimensional indicators were transferred into a single probabilistic space, which allowed performing a comparison and construct individual probabilistic models. An assessment of the influence degree for each indicator on the HF efficiency was carried out. Probabilistic analysis of indicators in different periods of HF implementation allowed identifying universal statistically significant dependencies. These dependencies do not change their parameters and can be used for forecasting in different periods of time. Criteria for the application of HF technology on a carbonate object have been determined. Using individual probabilistic models, integrated indicators were calculated, on the basis of which regression equations were constructed. Equations were used to predict the HF efficiency on forecast samples of wells. For each of the samples, correlation coefficients were calculated. Forecast results correlate well with the actual increase (values of the correlation coefficient r = 0.58-0.67 for the examined samples). Probabilistic method, unlike others, is simple and transparent. With its use and with careful selection of wells for the application of HF technology, the probability of obtaining high efficiency increases significantly.
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Date submitted2020-06-12
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Date accepted2020-06-15
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Date published2020-12-29
Analysis of project organization specifics in small-scale LNG production
- Authors:
- Pavel S. Tcvetkov
- S. V. Fedoseev
Gas industry plays an important role in the global energy sector, and in the coming decades amountsof natural gas production will only increase. One of the fastest growing trends in gas industry is the production of liquefiednatural gas (LNG), which is associated with the necessity to organize flexible systems of gas supply to the regions,remote from gas extraction sites. Industrial structure of LNG production includes projects, belonging to several different groups depending to their scale, in particular, small-scale production (SSLNG), cumulative production capacityof which is approximately 10 % from the industry-wide one. Economic aspects of implementing such projects remainunderexplored, which does not allow to draw objective conclusions regarding the prospects of their implementationin particular regions.This paper contains a review of publications, devoted to SSLNG project studies, aimed at identifying specifics oftheir organization compared to projects of greater scale. The results demonstrate that the majority of internationalcompanies classify projects as SSLNG, if their annual production capacity is below 0.5 million tonnes per annum.Specific capital costs, as well as implementation timelines of such projects, are several times lower than those of projects with greater production capacity, which reduces their risks and minimizes barriers to market entry. Furthermore,SSLNG is the most decentralized subsector in gas industry, aiming to cover the market due to a growing numberof projects, not their specific production capacity. These specific features define significant prospects of SSLNGdevelopment in Russia, both in the context of energy supply to remote regions and diversification of export deliveries.
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Date submitted2020-05-13
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Date accepted2020-11-12
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Date published2020-12-29
Improving the efficiency of terrigenous oil-saturated reservoir development by the system of oriented selective slotted channels
A comparative assessment of variation in the flow rate of oil production wells was performed taking into account increasing of perforated area of the productive part of the rocks, as well as recover of reservoir rocks permeability due to their unloading by creating slotted channels with the method of oriented slotted hydro-sandblast perforation. Different orientation directions and slotting intervals were analyzed, taking into account water encroachment of individual interlayers and azimuth direction of the majority of remaining reserves in separate blocks of the examined formation. In order to estimate development efficiency of terrigenous oil-saturated porous-type reservoirs by means of oriented slotted hydro-sandblast perforation, calculations were performed on a full-scale geological and hydrodynamic model of an oil field in the Perm Region. The object of modeling was a Visean terrigenous productive forma tion. The modeling of implementing oriented slotted hydro-sandblast perforation was carried out on a 3D filtration model for fourteen marginal wells, located in the zone with excessive density of remaining recoverable reserves and he terogeneous reserve recovery along the section. An optimal layout of slotted channels along the depth of the productive part of the well section was developed. Selective formation of 24 slotted channels was carried out con sidering the intervals of increased oil saturation. Comparative analysis of estimated flow rate of the wells was per formed for cumulative perforation of the examined productive formation and the developed method of slotted perforation. As a result of modeling, an increase in the oil average flow rate of 2.25 t/day was obtained. With oriented slotted hydro-sandblast perforation, incremental cumulative production for two years of prediction calculations per one well reached 0.5 thousand t.
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Date submitted2019-11-20
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Date accepted2020-01-20
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Date published2020-10-08
Effect of shear stress on the wall of technological pipelines at a gas condensate field on the intensity of carbon dioxide corrosion
The object of the study is a section of the gas and gas condensate collection system, consisting of an angle throttle installed on a xmas tree and a well piping located after the angle throttle. The aim of the study is to assess the impact of the flow velocity and wall shear stress (WSS) on the carbon dioxide corrosion rate in the area of interest and to come up with substantiated recommendations for the rational operation of the angle throttle in order to reduce the corrosion intensity. In the course of solving this problem, a technique was developed and subsequently applied to assess the influence of various factors on the rate of carbon dioxide corrosion. The technique is based on a sequence of different modeling methods: modeling the phase states of the extracted product, three-dimensional (solid) modeling of the investigated section, hydrodynamic flow modeling of the extracted product using the finite volume method, etc. The developed technique has broad possibilities for visualization of the obtained results, which allow identifying the sections most susceptible to the effects of carbon dioxide corrosion. The article shows that the average flow velocity and its local values are not the factors by which it is possible to predict the occurrence of carbon dioxide corrosion in the pipeline section after the angle throttle. The paper proves that WSS has prevailing effect on the corrosion intensity in the section after the angle choke. The zones of corrosion localization predicted according to the technique are compared with the real picture of corrosion propagation on the inner surface of the pipe, as a result of which recommendations for the rational operation of the angle throttle are formed.
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Date submitted2019-07-09
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Date accepted2019-09-26
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Date published2020-04-24
Development of mathematical models to control the technological properties of cement slurries
Oil and gas producing enterprises are making increasingly high demands on well casing quality, including the actual process of injection and displacement of cement slurry, taking into account requirements for the annular cement level, eliminating possible hydraulic fracturing, with developing a hydraulic cementing program. It is necessary to prevent deep invasion of cement slurry filtrate into the formation to exclude bridging of productive layers. It is impossible to fulfill all these requirements at the same time without application of modifying additives; complex cement compositions are being developed and applied more often. Furthermore, need to adjust cement slurries recipes appears for almost every particular well. In order to select and justify cement slurries recipes and their prompt adjustment, taking into account requirements of well construction project, as well as geological and technical conditions for cementing casing strings, mathematical models of the main technological properties of cement slurries for cementing production casing strings in the Perm Region were developed. Analysis of the effect of polycarboxylic plasticizer (Pl) and a filtration reducer (fluid loss additive) based on hydroxyethyl cellulose (FR) on plastic viscosity (V), spreadability (S) and filtration (F) of cement slurries is conducted. Development of mathematical models is performed according to more than 90 measurements.
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Date submitted2020-01-10
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Date accepted2020-01-14
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Date published2020-02-25
Biogeochemical assessment of soils and plants in industrial, residential and recreational areas of Saint Petersburg
Soils and plants of Saint Petersburg are under the constant technogenic stress caused by human activity in industrial, residential, and recreational landscapes of the city. To assess the transformed landscapes of various functional zones, we studied utility, housing, and park districts with a total area of over 7,000 hectares in the southern part of the city during the summer seasons of 2016-2018. Throughout the fieldwork period, 796 individual pairs of soil and plant samples were collected.A complex of consequent laboratory studies performed in an accredited laboratory allowed the characterization of key biogeochemical patterns of urban regolith specimens and herbage samples of various grasses. Chemical analyses provided information on the concentrations of polluting metals in soils and plants of different land use zones.Data interpretation and calculation of element accumulation factors revealed areas with the most unfavorable environmental conditions. We believe that a high pollution level in southern city districts has led to a significant degree of physical, chemical, and biological degradation of the soil and vegetation cover. As of today, approximately 10 % of the Technosols in the study area have completely lost the ability to biological self-revitalization, which results in ecosystem malfunction and the urgent need for land remediation.
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Date submitted2019-05-20
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Date accepted2019-07-12
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Date published2019-10-23
Development of Manufacturing Technology for High-Strength Hull Steel Reducing Production Cycle and Providing High-Quality Sheets
The article presents the results of scientific research and industrial experiments aimed at the development of technology to reduce the production cycle of high-strength hull steel. The technology includes an improved reduced heat treatment of ingots made using rare-earth metals and uphill teeming of large sheet ingots. The proposed technology for the preliminary heat treatment of ingots eliminates the high-temperature phase re- crystallization operation, which is unnecessary, according to the authors, since it does not allow partial crushing (grinding) of the metal dendritic structure and homogenization. When using the proposed technology of reduced pre- treatment, phase and structural stresses are sharply reduced. Experiments have shown that the modification of steel with rare-earth metals has a positive effect on the crystallization of ingots, changing the macro- and microstructure of alloy steel. The developed manufacturing technology of high-strength hull steel provides a high level of sheet quality and a reduction in the production cycle time by 10-12 %.
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Date submitted2019-04-28
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Date accepted2019-06-28
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Date published2019-10-23
Determination of Optimal Fluorine Leaching Parameters from the Coal Part of the Waste Lining of Dismantled Electrolytic Cells for Aluminum Production
- Authors:
- N. V. Nemchinova
- A. A. Tyutrin
- V. V. Somov
When aluminum is obtained by electrolysis of cryolite-alumina melts when the baths are sent for capital repairs, a solid technogenic product is formed – waste lining of electrolytic cells (WLEC). The volume of formation of WLEC is 30-50 kg per 1 ton of aluminum. Currently, it is mainly stored at landfills near industrial enterprises, causing harm to the environment. However, this technogenic raw material contains valuable components (fluorine, aluminum, sodium) that can be extracted to produce fluoride salts, which are in demand during the electrolytic production of aluminum. The objects of research were samples of the coal part of the waste lining of dismantled S-8BM (E) type electrolytic cells of «RUSAL Krasnoyarsk» JSC (Krasnoyarsk) of RUSAL company. According to the X-ray experiment diffraction analysis (using a Bruker D8 ADVANCE diffractometer) of the phase composition of the samples, it was found that the main fluorine-containing compounds are cryolite, chiolite, sodium and calcium fluorides. The total fluorine content in the studied samples averaged 13.1 %. We conducted studies on the leaching of fluorine from WLEC with a solution of caustic alkali (NaOH concentration – 17.5 g/dm 3 ). The process was carried out in a mechanically agitated reactor using a BIOSAN MM-1000 top drive laboratory stirrer with a two-blade nozzle. By the method of mathematical planning of a three-factor experiment, the mutual influence of three leaching conditions on the optimization parameter was established – the extraction of fluorine in solution (in percent). The maximum recovery of fluorine from WLEC to the leach solution averaged 86.4 % and was achieved with the following indicators:processtemperature–95 ° C, the ratio ofliquidtosolidphase–9:1,duration– 210 min.
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Date submitted2019-03-24
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Date accepted2019-05-13
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Date published2019-08-23
Calculation of Oil-saturated Sand Soils’ Heat Conductivity
- Authors:
- J. Sobota
- V. I. Malarev
- A. V. Kopteva
Nowadays, there are significant heavy high-viscosity oil reserves in the Russian Federation with oil recovery coefficient not higher than 0.25-0.29 even with applying modern and efficient methods of oil fields development. Thermal methods are the most promising out of the existing ways of development, main disadvantage of which is large material costs, leading to the significant rise in the cost of extracted oil. Thus, creating more efficient thermal methods and improving the existing ones, is the task of great importance in oil production. One of the promising trends in enhancing thermal methods of oil recovery is the development of bottomhole electric steam generators. Compared to the traditional methods of thermal-steam formation treatment, which involve steam injection from surface, well electrothermal devices can reduce energy losses and improve the quality of steam injected into the formation. For successful and efficient organization of oil production and rational development of high-viscosity oil fields using well electrothermal equipment, it is necessary to take into account the pattern of heat propagation, both in the reservoir and in the surrounding space, including the top and bottom. One of the main values characterizing this process is the heat conductivity λ of oil-bearing rocks. The article describes composition of typical oil-saturated sand soils, presents studies of heat and mass transfer in oil-saturated soils, reveals the effect of various parameters on the heat conductivity of a heterogeneous system, proposes a method for calculating the heat conductivity of oil-bearing soils by sequential reduction of a multicomponent system to a two-component system and proves the validity of the proposed approach by comparing acquired calculated dependencies and experimental data.
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Date submitted2019-03-11
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Date accepted2019-05-11
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Date published2019-08-23
Estimate of Radial Drilling Technology Efficiency for the Bashkir Operational Oilfields Objects of Perm Krai
- Authors:
- S. V. Galkin
- A. A. Kochnev
- V. I. Zotikov
The radial drilling technology efficiency for carbonate bashkir deposits of Perm Krai is considered. The geological structure of a productive part of bashkir layer is characterized by high degree of heterogeneity that promotes while drilling radial channels involvement in development additional interlayers that earlier was not drained. During the analysis the main geological process parameters affecting drilling technology efficiency were revealed. According to the dynamics of average daily oil production growth, palettes were built to forecast additional oil production as a result of radial drilling activities. Using the pallets, it is possible to predict the total additional oil production, well operating time with the effect of radial drilling and average daily oil production growth for each year. It was found that hydrochloric acid treatments performed on wells prior to radial drilling significantly reduce the effectiveness of radial drilling technology. For such wells, the value of the correction is statistically substantiated, which reduces the predictive estimate of the increase in oil production. A model was built to assess the increase in oil production in the first year after the event and an algorithm for calculating the total additional oil production was developed using linear discriminant analysis. For the resulting model, errors are calculated that are compared with the forecast efficiency of standard methods for oil-producing enterprises. This model shows a much more accurate correspondence of forecast results to actual technology application results. The probability of the event high efficiency increases significantly with a more detailed approach to the selection of wells for radial drilling. According to the forecast methodology, the technology’s efficiency was calculated and recommendations for its implementation for the wells of the Bashkir production objects were made in the interests of an oil-producing enterprise.
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Date submitted2018-01-01
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Date accepted2018-03-24
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Date published2018-06-22
Complex petrophysical correction in the adaptation of geological hydrodynamic models (on the example of Visean pool of Gondyrev oil field)
- Authors:
- V. A. Repina
- V. I. Galkin
- S. V. Galkin
The authors review a method of combined porosity and volume density correction in the process of modeling the distribution of reservoir permeability. Basing on petrophysical investigations of core samples from Bashkir fold deposits, an association between rock porosity, density and permeability has been analyzed. Significant correlation has been observed for the above mentioned parameters in porous collectors in contrast to reduced correlation for dense rocks and intervals of anomalously high poroperm characteristics. For terrigene porous collectors the authors propose a model of permeability assessment based on combined porosity and density correction. A modified model was developed for Visean pool of Gondyrev oil field, where collector permeability had been calculated as a function of rock porosity and density. The modified model has been compared to the conventional one; significant differences have been detected. In the modified version maximum permeability is associated with the southern part of the pool, whereas the conventional method points out the central part and predicts lowering permeability closer to the periphery. Geological model in the modified version is more homogenous than the conventional one and has no sharp peaks and valleys. The calculations have been made that reproduce the history of field development for both permeability volumes. Authors demonstrate that total oil production obtained using the modified model has a much better correlation with the actual data. The best results from using suggested method apply to the initial stage of development due to better convergence of high-rate wells. On the whole, comparison of two methods shows that for the purposes of production history adaptation the modified model is significantly better than the conventional one. Hence, the method of density correction allows for better justification of differences in the lithology of Visean collectors, which ultimately results in higher accuracy of data on residual oil reserves in the deposit.
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Date submitted2016-10-27
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Date accepted2017-01-02
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Date published2017-04-14
Chemistry as a basis for solving environmental issues
- Authors:
- V. E. Kogan
- T. S. Shakhparonova
The article summarizes over 40 years of authors’ experience in the field of physical chemistry and chemical technology of glassy state of materials. It is shown that environmental issues are caused not by Chemistry as a science but by actions of ecologically illiterate humans using its advances. It is noted that without chemistry humankind cannot live comfortably and solve existing environmental problems. In support these facts we describe several developments made by authors of this article in energy industry, high temperature machinery, glass production technology, glassy phosphate fertilizers, production of non-waste systems and complex research of physical-chemical principles of glassy oil sorbents production of organic and non-organic nature.