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Date submitted2022-09-30
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Date accepted2024-11-07
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Date published2025-02-25
Carbon dioxide corrosion inhibitors: current state of research and development
Among the methods of corrosion control in the oil and gas production industry the leading place belongs to inhibitor protection, since there is no need for technological and technical changes in the existing equipment. The combination of high variability of inhibitor composition with changing conditions of its application and low capital investments makes it an indispensable reagent at oil and gas fields. The main classes of compounds used as active bases of carbonic acid corrosion inhibitors for the protection of oil and gas equipment are described. Classical organic active bases containing heteroatoms (oxygen, sulfur, nitrogen) are examined. Special attention was paid to alkylimidazolines and other nitrogen-containing compounds as the most frequently used as active bases of carbonic acid corrosion inhibitors in Russia and abroad. A wide range of possibilities to achieve the desired properties of corrosion inhibitors by varying the substitutes has been demonstrated. Nowadays, in addition to the traditional requirements for corrosion inhibitors, their safety for the environment is equally important. The information on prospective research and development aimed at improving the environmental characteristics of the reagents used is given. Plant extracts, synthetic and biological polymers involved in traditional corrosion inhibitors or used as new independent compounds are considered. It is shown that the effectiveness of corrosion inhibitors significantly depends on the pH of the medium, temperature, partial pressure of СО2, flow rate, and other factors.
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Date submitted2023-04-11
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Date accepted2023-09-20
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Date published2023-10-27
Current state of above-ground and underground structures of the Alexander Column: an integral basis for its stability
- Authors:
- Regina E. Dashko
- Angelina G. Karpenko
The Alexander Column as a compositional center of the architectural ensemble of Palace Square in Saint Petersburg, Russia, has always been a matter of concern for both the public and specialists due to progressive deterioration of its granite shaft caused by crack formation. The article examines previous studies related to the inspection and restoration of the column's shaft and other parts above ground level, as well as reasons for crack initiation and propagation in the column. An analysis was performed on the anomalies in the Fennoscandian Shield and the structural-tectonic conditions at the Montferrand quarry site, revealing the presence of faults and circular features within the studied area. The research considers N.Hast's measurements of excess tectonic stresses in anomaly zones (southeastern Finland), which acted horizontally and resulted in the development of tensile cracks within the granite massif and later in the column’s shaft after its installation. The most dangerous type of deformation for the Alexander Column is its tilt in the northeast direction, recorded in 1937 and 2000. The article analyzes the construction features of the column's foundations and additional underground elements, as well as soil and groundwater characteristics based on archival data. The contamination history of the underground space is taken into account, and an analogy-based method is used to assess the engineering-geological and hydrogeological conditions of the underground load-bearing structures within the placement zone of the Alexander Column and the New Hermitage buildings. The results of visual observations on the nature of deterioration and deformation of the pavement around the monument, as well as its pedestal, indicating the development of uneven settlement of the foundation, are presented. The article concludes with general recommendations for organizing and implementing comprehensive monitoring to forecast the deformation dynamics of the Alexander Column.
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Date submitted2022-07-10
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Date accepted2023-06-20
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Date published2024-02-29
Mathematical modeling of the electric field of an in-line diagnostic probe of a cathode-polarized pipeline
A mathematical model of the in-line control of the insulation resistance state for cathodically polarized main pipelines according to electrometry data is considered. The relevance of the work is caused by the opportunity to create in-line internal isolation defects indicators of the main pipelines for transported liquids that are good conductors and expand the functionality of monitoring and controlling cathodic protection systems of the main pipelines. Features of the mathematical model are: consideration of the electric conductivity of transported liquid influence on electric field distribution; consideration of the influence of external and internal insulating coating resistance; use of the electric field of an in-line diagnostic probe for quality control of internal insulation. Practical significance consists in the development of modeling methods for control subsystems of main pipeline protection against corrosion and the development of special mathematical and algorithmic support systems for monitoring and controlling the operating modes of the cathodic protection station of main pipelines.
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Date submitted2022-03-25
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Date accepted2022-09-06
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Date published2022-12-29
Autoclave modeling of corrosion processes occurring in a gas pipeline during transportation of an unprepared multiphase medium containing CO2
The problem of selecting a method for ensuring the reliability of the unprepared fluid transport facilities of an unprepared fluid in the presence of carbon dioxide is considered. Carbon dioxide corrosion is one of the dangerous types of damage to field and main pipelines. It has been shown that dynamic autoclave tests should be carried out during staged laboratory tests in order to determine the intensity of carbon dioxide corrosion and to select the optimal method of protection. A hypothesis about the imperfection of the existing generally accepted approaches to dynamic corrosion testing has been put forward and confirmed. A test procedure based on the use of an autoclave with an overhead stirrer, developed using elements of mathematical modeling, is proposed. The flows created in the autoclave provide corrosive wear of the sample surface similar to the internal surfaces elements wear of the pipelines piping of gas condensate wells. The autoclave makes it possible to simulate the effect of the organic phase on the flow rate and the nature of corrosion damage to the metal surface, as well as the effect of the stirrer rotation speed and, accordingly, the shear stress of the cross section on the corrosion rate in the presence/absence of a corrosion inhibitor. The given results of staged tests make it possible to judge the high efficiency of the developed test procedure.
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Date submitted2021-12-16
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Date accepted2022-04-07
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Date published2022-07-13
The Upper Kotlin clays of the Saint Petersburg region as a foundation and medium for unique facilities: an engineering-geological and geotechnical analysis
- Authors:
- Regina E. Dashko
- Georgiy A. Lokhmatikov
The article reviews the issues concerned with correctness of the engineering-geological and hydrogeological assessment of the Upper Kotlin clays, which serve as the foundation or host medium for facilities of various applications. It is claimed that the Upper Kotlin clays should be regarded as a fissured-block medium and, consequently, their assessment as an absolutely impermeablestratum should be totally excluded. Presence of a high-pressure Vendian aquifer in the lower part of the geological profile of the Vendian sediments causes inflow of these saline waters through the fissured clay strata, which promotes upheaval of tunnels as well as corrosion of their lining. The nature of the corrosion processes is defined not only by the chemical composition and physical and chemical features of these waters, but also by the biochemical factor, i.e. the availability of a rich microbial community. For the first time ever, the effect of saline water inflow into the Vendian complex on negative transformation of the clay blocks was studied. Experimental results revealed a decrease in the clay shear resistance caused by transformation of the structural bonds and microbial activity with the clay’s physical state being unchanged. Typification of the Upper Kotlin clay section has been performed for the region of Saint Petersburg in terms of the complexity of surface and underground building conditions. Fissuring of the bedclays, the possibility of confined groundwater inflow through the fissured strata and the consequent reduction of the block strength as well as the active corrosion of underground load-bearing structures must be taken into account in designing unique and typical surface and underground facilities and have to be incorporated into the normative documents.
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Date submitted2021-04-30
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Date accepted2021-11-30
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Date published2021-12-27
Methodology for testing pipeline steels for resistance to grooving corrosion
- Authors:
- Viktor I. Bolobov
- Grigoriy G. Popov
The methodology for testing pipeline steels is suggested on the assumption that for the destruction of pipes in field oil pipelines by the mechanism of grooving corrosion the simultaneous fulfillment of such conditions as the occurrence of scratches on the lower generatrix of the pipe, eventually growing into a channel in the form of a groove, emulsion enrichment with oxygen, presence of pipe wall metal in a stressed state, presence of chlorine-ion in the oil-water emulsion is required. Tests are suggested to be carried out in 3 % aqueous solution of NaCl with continuous aeration by air on bent plates 150×15×3 mm, made of the analyzed steel, the middle part of which is under the action of residual stresses σ res , close to the level of maximum equivalent stresses σ eqv in the wall of the oil pipeline, with the presence of a cut on this part on the inner side of the plate as an initiator of additional mechanical stresses. Using the value of the modulus of normal elasticity of the analyzed steel, the degree of residual strain of the elastic-plastic body from this material, corresponding to the value σ res ≈ σ eqv is calculated, based on which the plates are bent to the required deflection angle, after which the cut is applied to them. After keeping the plates in the corrosive medium for each of them the increase in depth of the cut as a result of corrosion of the walls by the corrosive medium is analyzed, from which the rate of steel K by the mechanism of grooving corrosion is calculated taking into account the duration of tests. Corrosion rate values for two pipe steel grades determined by the suggested procedure are given. The comparison of K values obtained leads to the conclusion about the higher resistance to grooving corrosion of 09G2S steel.
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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 submitted2021-03-10
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Date accepted2021-05-21
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Date published2021-09-20
Influence of heat treatment on the microstructure of steel coils of a heating tube furnace
- Authors:
- Vladimir Yu. Bazhin
- Bashar Issa
Transportation and refining of heavy metal-bearing oil are associated with the problems of localized destruction of metal structures and elements due to corrosion. In the process of equipment operation, it was revealed that premature failure of steel coils of heating tube furnaces at oil refineries and petrochemical plants was associated with insufficient strength and corrosion resistance of the steelwork. The study of the effect that structure and phase composition of 15KH5M-alloy steel elements of heating furnaces at oil refineries have on the corrosion properties, associated with mass loss and localized destructions in the process of heat treatment, allows to develop protective measures and determine heating modes with a rate-limiting step of oxidation. The rate of various corrosion types of 15KH5M steel is used as an indicator to assess the effectiveness of the applied modes of coil heat treatment in order to increase their corrosion resistance and improve their operational characteristics. Conducted experiments on heat treatment of certain steel coil sections allowed to determine rational heating modes for the studied coils, which made it possible to reduce their mass loss and increase corrosion resistance of working surfaces in the process of operation. Proposed heat treatment of steel coils at specified intervals of their operation in the tube furnaces creates conditions for their stable performance and affects the degree of industrial and environmental safety, as well as reduces material costs associated with the repair and replacement of individual assemblies and parts of tube furnaces.
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Date submitted2021-01-21
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Date accepted2021-02-24
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Date published2021-04-26
Forecasting of mining and geological processes based on the analysis of the underground space of the Kupol deposit as a multicomponent system (Chukotka Autonomous Region, Anadyr district)
- Authors:
- Regina E. Dashko
- Ivan S. Romanov
The underground space of the Kupol deposit is analyzed as a multicomponent system – rocks, underground water, microbiota, gases (including the mine atmosphere) and supporting structures – metal support and shotcrete (as an additional type of barring) and also stowing materials. The complex of host rocks is highly disintegrated due to active tectonic and volcanic activity in the Cretaceous period. The thickness of sub-permafrost reaches 250-300 m. In 2014, they were found to contain cryopegs with abnormal mineralization and pH, which led to the destruction of metal supports and the caving formation. The underground waters of the sub-permafrost aquifer are chemically chloride-sulfate sodium-calcium with a mineralization of 3-5 g/dm 3 . According to microbiological analysis, they contain anaerobic and aerobic forms of microorganisms, including micromycetes, bacteria and actinomycetes. The activity of microorganisms is accompanied by the generation of hydrogen sulfide and carbon dioxide. The main types of corrosion – chemical (sulfate and carbon dioxide), electrochemical and biocorrosion are considered. The most hazardous is the biocorrosion associated with the active functioning of the microbiota. Forecasting and systematization of mining and geological processes are carried out taking into account the presence of two zones in depth – sub-permafrost and below the bottom of the sub-permafrost, where mining operations are currently underdone. The importance of assessing the underground space as a multicomponent environment in predicting mining and geological processes is shown, which can serve as the basis for creating and developing specialized monitoring complex in difficult engineering and geological conditions of the deposit under consideration.
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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 submitted2018-08-30
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Date accepted2018-10-26
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Date published2019-02-22
Study of bearing units wear resistance of engines career dump trucks, working in fretting corrosion conditions
- Authors:
- Ju. Olt
- V. V. Maksarov
- V. A. Krasnyy
The occurrence of fretting corrosion on nominally fixed surfaces of high-loaded parts of mining machines and mechanisms is considered. Examples of wear and damage of critical parts, bearing assemblies of engines of dump trucks in fretting conditions are given. The mechanisms of fretting corrosion when using wear-resistant coatings are considered. It is noted that when choosing protective thin-layer coatings that provide an increase in the fretting-resistance of surfaces of tightly contacting parts, it is necessary to take into account both their wear resistance and the ability to resist shear. At the same time, the thickness of such coatings allows preserving, during operation, those provided during the assembly of the tension, without disturbing the maintainability of the nodes. The results of research of fretting wear of a number of coatings on a special installation are given. The mechanisms of wear of a number of thin-layer coatings based on friction-mechanical brazing, polymer fluorocarbon composition, solid lubricant coating using scanning electron microscopy were studied. Recommendations on the use of the studied thin-layer coatings for high-loaded parts of mining machines operating in fretting corrosion conditions have been developed. The aim of the work was to study the effect of a number of thin-layer coatings on the wear of highly loaded connections of the mechanisms of mining machines, in particular bearing assemblies of quarry dump trucks operating under fretting corrosion conditions.
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Date submitted2018-01-23
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Date accepted2018-02-25
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Date published2018-06-22
Influence of post-welding processing on continuous corrosion rate and microstructure of welded joints of steel 20 and 30KHGSA
- Authors:
- A. M. Shchipachev
- S. V. Gorbachev
Welded joints of structure steels have lower corrosion resistance in comparison to base metal. To increase corrosion resistance of welded joints and heat-affected zone they use longtime and energy-consuming methods of thermal and mechanic processing. The article covers the possibility of using the superplasticity deformation (SD) effect for processing of welded joints. The effect of SD is that metals and alloys with a small grain size (of the order of 10 μm) under conditions of isothermal deformation at a certain temperature acquire the ability for unusually large plastic deformations while reducing the deformation resistance. Grain-boundary sliding during superplasticity provides a high degree of structural homogeneity. If the metal does not have the small grain size, then during isothermal deformation at appropriate temperature the SD effect will not be fully manifested but will cause relaxation of residual micro and macro strains, recrystallization, which can be used during processing of welded joints to ensure their full strength. There have been carried out the investigation of processing methods impact - SD, thermal cycling and influence of post-welding treatment on corrosion rate and microstructure of steels 20 and 30KhGSA. It is shown that after deformation in superplasticity mode there is low corrosion rate and more favorable microstructure in the studied samples of steel. Post-welding processing of welded joints in SD mode provides low tool loads and low energy costs.
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Date submitted2015-10-11
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Date accepted2015-12-13
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Date published2016-08-22
The specifics of operating minor deposits (as given by the examples of gas condensate deposits of the Northern Caucasus)
- Authors:
- R. A. Gasumov
One of the most important directions in upgrading well productivity in the process of mining hydrocarbons consists in fighting with salt formation and salt deposition. Solving that problem becomes especially actual when operating deposits that are in their final stage of exploitation in complex mining and geological conditions accompanied by deposition of salts in the well foot area of oil bed and their sedimentation on the sub-surface and surface equipment. It provokes a drop in well productivity and results in off-schedule repair works. Specifics are considered of exploiting minor gas condensate deposits of the Northern Caucasus that are operated under complicated mining and geological conditions of anomalously high bed pressures, high temperatures, strong depressions on the beds and inflow of mineralized water from water saturated seams. Processes are studied of salt deposition from heavy hydrocarbons in the well foot and the bed area surrounding it. Water sample analyses data from different wells have demonstrated that the main salts carrier is the associated water, and the principal sedimenting agents are corrosion products, as confirmed by the results of microscopic studies. The dynamics is presented of salt deposition in the “well foot – wellhead – separator” system retrieved from the results of studies of reaction products in the well foot zone of oil bed. It is demonstrated that the efficiency of struggling with salt deposition in the course of mining hydrocarbons depends on comprehensive approach to the problem, the principal thrust lying with prevention of such deposition. Possible ways are considered to prevent precipitation of ferric compounds in the course of operating gas condensate wells, a way is suggested to intensify gas inflow.
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Date submitted2015-08-25
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Date accepted2015-10-24
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Date published2016-04-22
The modern technology of drilling and casing of well during the exploration of gas hydrates
- Authors:
- N. I. Nikolaev
- Lyu Tyanle
In the paper, the perspectives of exploration and completion of gas hydrate fields and the drilling problems in the gas hydrates of the northwest china are studied. It has been established, that the main reasons of complications in the Muli field are the secondary hydrate formation on the walls of the well and drilling assembly and ice formation inside the set cement during the well drilling and completion in permafrost. It has been shown, that in the areas with permafrost during the drilling of the layers containing gas hydrates, temperature and pressure changes can lead to the dissociation of hydrates. At the same time, pressure increase in the annular space due to the gas release, can lead to the secondary formation of gas hydrates, drill string stuck, ceasing of drilling fluid circulation, which is the reason of serious trouble in the wellbore. The results of the research on the development of drilling fluids compositions, which lower the drilling troubles of permafrost, are presented. Comparative experiments have been conducted to evaluate the effectiveness of thermodynamic and kinetic inhibitors, which prevent the repeated hydrate formation. It has been established, that the kinetic inhibitors have the clear advantage: they have good inhibiting effects even with low amounts of additives. In the laboratory conditions, the researches have been conducted to evaluate the phase equilibrium of gas hydrates during their reaction with the water solutions, containing kinetic inhibitor PVP. A thin clay drilling mud has been developed on the water base, providing the holding of the temperature in the level of –2 °С and its effectiveness for the gas hydrate fields in the PRC has been shown. Casing effectiveness of unstable rocks during the drilling in the conditions of negative temperatures inside the well largely depends on their physical-mechanical properties, composition and the technical indicators of cement materials. The authors suggest the composition of quick-setting cements based on aluminum binding materials. It has been established, that the analyzed compositions have the ability to considerably improve the results of cementing.
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Date submitted2009-08-19
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Date accepted2009-10-02
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Date published2010-02-01
The estimation features of vulnerability and desintegration оf subway construction materials in Saint Petersburg
- Authors:
- P. V. Kotyukov
In this paper the features of subway construction materials degradation depending on engineering-geological, hydro-geological and geoecological conditions of Saint Petersburg underground space are considered. The basic types of subway construction placing and their destruction specificity depending on influence of water-bearing horizons hydrodynamic and hydro chemical conditions, natural and natural-technogenic gas bio-production and microbial activity are analyzed. The examples of the disintegrated materials and new growths (salt efflorescence, stalactites and others) chemical compound features depending on the content of ground waters basic components affecting on tunnels lining are resulted.