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Date submitted2024-03-29
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Date accepted2024-11-07
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Date published2025-02-26
Well killing with absorption control
The development of new fields with low-permeability reservoirs required the introduction of new production technologies, of which the most significant for well killing and underground repair were multi-ton hydraulic fracturing, the simultaneous operation of two or three development sites by one well grid, and an increase in the rate of fluid extraction. These global decisions in field development have led to the need to search for new effective materials and technologies for well killing. The article is devoted to the analysis of problems associated with the process of killing production wells in fields characterized by increased fracturing, both natural and artificial (due to hydraulic fracturing), with reduced reservoir pressure and a high gas factor. The relevance of the analysis is due to the increase in the number of development sites where complications arise when wells are killed. Particular attention is paid to technical solutions aimed at preserving the filtration and capacity properties of the bottomhole formation zone, preventing the absorption of process fluid, and blocking the manifestation of gas. The classification of block-packs used in killing is given, based on the nature of the process fluid. Suspension thickened water-salt solutions are considered, forming a waterproof crust on the surface of the rock, which prevents the penetration of water and aqueous solutions into the formation. This approach ensures the safety and efficiency of killing operations, especially when working with formations in which maintaining water saturation and preventing the ingress of the water phase are of critical importance. Modern trends in the development of technology are revealed, and promising areas for further improvement of well killing with absorption control are outlined.
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Date submitted2024-03-30
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Date accepted2024-06-13
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Date published2024-07-04
Organotin pollutants in emerging coastal-marine sediments of the Kaliningrad shelf, Baltic Sea
Based on two years of monitoring of modern bottom sediments of two sections of the Kaliningrad shelf of the Baltic Sea – “Curonian Spit” and “Northern Sambian” – an assessment of the sources of pollution with organotin compounds (OTs) and heavy metals was carried out. The content of individual organotin compounds and OTCs spectra obtained by gas chromatography with mass spectrometry of relatively coarse-grained bottom sediments indicate the presence of organotins in significant quantities – the total OTs content (ΣOTs) is from 0.6 to 8.3 ng/g. However, the content of tributyltin (TBT), the main component of anti-fouling systems for marine vessels and the most dangerous endocrine-disrupting compound among the hazardous substances for marine ecosystems, is at a low level (0-2.3 ng/g) in all studied samples and has not increased over the two-year observation period (biodegradation index 1.7-12.4). At the same time, the presence of abnormally high concentrations of mono-, triphenyl- and tricyclohexyltin in the sediments of the ”Northern Sambian” site (up to 30, 7 and 6.4 ng/g, respectively) indicates an additional source of pollution of coastal waters and shelf sediments (for example, plastic litter and agricultural runoff). The absence of significant shipping in the study areas ensures a consistently low level of pollution with tributyltin and its derivatives (less than 0.3 and 2.3 ng/g of TBT in 2017 and less than 0.1 and 1.3 ng/g in 2018 for the sites “Curonian Spit” and “Northern Sambian”, respectively), which indicates the activity of the processes of TBT transformation and self-cleaning of sandy sediments. However, the identified trends and their predictive accuracy require long-term observation and monitoring of the sediment environment using data on the deep-water part of the shelf, enriched in clay and humus components.
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Date submitted2023-03-20
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Date accepted2023-09-20
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Date published2023-10-27
Experimental simulation of a system of swamp biogeocenoses to improve the efficiency of quarry water treatment
Mining activities were producing large quantities of wastewater contaminated with nitrogen compounds and metals. With insufficient treatment, these pollutants are released into the environment and have a toxic effect on living organisms. Constructed wetlands are now widely adopted as wastewater treatment systems because of the combination of physical, chemical and biological processes for the removal of contaminants. In this study, an experimental system was modeled to improve the efficiency of the quarry wastewater treatment of a mining enterprise by sharing the higher aquatic vegetation: broad-leaved cattail (Typha latifolia L.), common water-plantain (Alisma plantago-aquatica L.), jointed rush (Juncus articulatus L.) and lower aquatic vegetation (Chlorella sp.). Concentrations of nitrogen compounds and metal were analyzed both in the model and in the treated solution of quarry wastewater for calculation of treatment efficiency. Concentrations of the pollutants in the tissues of the higher aquatic vegetation were analyzed to assess the accumulation capacity and efficiency of translocation of the pollutants. The results of the experimental study showed the practical applicability of the constructed integrated treatment system to reduce the concentration of pollutants in quarry wastewater, as well as increasing the efficiency of treatment by introducing lower aquatic vegetation into the system
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Date submitted2022-09-30
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Date accepted2023-02-13
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Date published2024-02-29
Improving the efficiency of oil vapor recovery units in the commodity transport operations at oil terminals
- Authors:
- Vladimir V. Pshenin
- Gulnur S. Zakirova
In this paper the problem of losses from evaporation of light fractions of hydrocarbons during loading operations of tanker fleets vessels is considered. It was found that there is no unified approach to modeling the system “tanker – gas phase pipeline – vapor recovery units” in open sources. The absence of a generally recognized model makes it impossible to scientifically justify the application of instruments to reducing losses and the development of corresponding measures. In work it is showed that the dynamics of growth of pressure in the inner tanker capacity is described by a differential equation, considering for non-stationary essence of the process. This equation is converted to a non-dimensional form and investigated in relation to the similarity criteria of this system. This research has allowed to establish unambiguously the general character of pressure changes in the inner tanker capacity, and to predict the peak values of its growth at the initial stage of the loading operation. The obtained equations were tested on real tanker loading data and showed satisfactory convergence with the experimental data. At different stages of the loading opera-tion the component composition of vapor changes, which is shown by chromatographic analysis of the gas mixture. With the availability of a model of hydrocarbon vapor displacement from the inner of tanker, it is possible to propose measures to minimize the negative impact on the environment and return valuable vapors of the product to the technological chain of transportation.
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Date submitted2022-04-12
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Date accepted2022-11-17
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Date published2022-12-29
Development of technological solutions for reliable killing of wells by temporarily blocking a productive formation under ALRP conditions (on the example of the Cenomanian gas deposits)
Modern field operation conditions are characterized by a decline in gas production due to the depletion of its reserves, a decrease in reservoir pressure, an increase in water cut, as well as due to the depreciation of the operating well stock. These problems are especially specific at the late stage of development of the Cenomanian deposits of Western Siberia fields, where the anomaly factor below 0.2 prevails, while gas-bearing formations are represented mainly by complex reservoirs with high-permeability areas. When killing such wells, the classical reduction of overbalance by reducing the density of the process fluid does not provide the necessary efficiency, which requires the search for new technical and technological solutions. In order to prevent the destruction of the reservoir and preserve its reservoir properties during repair work in wells with abnormally low reservoir pressure, AO “SevKavNIPIgaz” developed compositions of special process fluids. A quantitative description of the process of blocking the bottomhole formation zone is proposed by means of mathematical modeling of injection of a gel-forming solution into a productive horizon. The well killing technology includes three main stages of work: leveling the injectivity profile of the productive strata using three-phase foam, pumping the blocking composition and its displacement with the creation of a calculated repression. Solutions obtained on the basis of a mathematical model allow optimizing technological parameters to minimize negative consequences in the well killing process.
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Date submitted2021-03-16
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Date accepted2021-07-27
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Date published2021-10-21
Allocation of a deep-lying brine aquifer in the rocks of a chemogenic section based on the data of geophysical well logging and 2D seismic exploration
Advancement in the production of potassium fertilizers is an important strategic task of Russian agricultural industry. Given annually growing production rates, the reserves of discovered potassium-magnesium salt deposits are noticeably decreasing, which creates the need to ensure stable replenishment of the resource base through both the discovery of new deposits and the exploitation of deep-lying production horizons of the deposits that are already under development. In most cases, deposits of potassium-magnesium salts are developed by underground mining. The main problem for any salt deposit is water. Dry salt workings do not require any additional reinforcement and can easily withstand rock pressure, but with an inflow of water they begin to collapse intensively – hence, special attention is paid to mine waterproofing. Determination of spatial location, physical and mechanical properties of the aquifer and water-blocking stratum in the geological section represent an important stage in the exploration of a salt deposit. The results of these studies allow to validate an optimal system of deposit development that will minimize environmental and economic risks. On the territory of Russia, there is a deposit of potassium-magnesium salts with a unique geological structure – its production horizon lies at a considerable depth and is capped by a regional aquifer, which imposes significant limitations on the development process. To estimate parameters of the studied object, we analyzed the data from CDP seismic reflection survey and a suite of methods of radioactive and acoustic well logging, supplemented with high-frequency induction logging isoparametric sounding (VIKIZ) data. As a result of performed analysis, we identified location of the water-bearing stratum, estimated average thickness of the aquifers and possible water-blocking strata. Based on research results, we proposed methods for increasing operational reliability of the main shaft in the designed mine that will minimize the risks of water breakthrough into the mine shaft.
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Date submitted2020-07-02
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Date accepted2021-02-16
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Date published2021-04-26
Development of viscoelastic systems and technologies for isolating water-bearing horizons with abnormal formation pressures during oil and gas wells drilling
Article provides a brief overview of the complications arising during the construction of oil and gas wells in conditions of abnormally high and abnormally low formation pressures. Technological properties of the solutions used to eliminate emergency situations when drilling wells in the intervals of catastrophic absorption and influx of formation fluid have been investigated. A technology for isolating water influx in intervals of excess formation pressure has been developed. The technology is based on the use of a special device that provides control of the hydrodynamic pressure in the annular space of the well. An experiment was carried out to determine the injection time of a viscoelastic system depending on its rheology, rock properties and technological parameters of the isolation process. A mathematical model based on the use of a special device is presented. The model allows determining the penetration depth of a viscoelastic system to block water-bearing horizons to prevent interformation crossflows and water breakthrough into production wells.
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Date submitted2019-07-17
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Date accepted2019-09-04
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Date published2019-12-24
On flood protection measures for potash mines
- Authors:
- A. A. Baryakh
- E. A. Gubanova
Development of water-soluble ore deposits is associated with the necessity to preserve water blocking strata (WBS), which separate aquifers from the mine gob. One indicator of the rate of man-induced load on WBS layers is subsidence of the earth surface, which defines the character of shift trough formation of the earth surface. The greatest threat of WBS discontinuity is posed by the areas located at the edges of a shift trough. From the perspective of Upper Kama deposit of potassium and magnesium salts, by means of mathematical modelling methods authors demonstrated that in the capacity of threat indicators of WBS hole destruction it is possible to use the following parameters of a shift trough: edge length scaled to the depth of mining operations and maximum subsidence of the earth surface. Critical combination of these factors is responsible for the discontinuity at the edges of water blocking strata. These parameters of a shift trough can easily be controlled by instrumental procedures and can be included in the basics of a general monitoring system of WBS state at potash mines. In order to protect the mine from the inrush of fresh water, it is necessary to form softening zones at the edges of mined-out areas near permanent or temporary borders of mining operations. Authors review different options of softening zone formation. Numerical tests have demonstrated that the most efficient way to protect water blocking strata is the formation of softening zones by means of backfilling the stopes of the workable seam or its exclusion from mining operations.
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Date submitted2018-09-10
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Date accepted2018-11-06
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Date published2019-02-22
Comparative analysis of zincand tin oxidation with acids at room temperatures
- Authors:
- S. D. Pozhidaeva
- L. S. Ageeva
- A. M. Ivanov
The paper analyses the parameters of deep oxidation of zinc and tin by copper (II) compounds and molecular iodine in the presence of molecular oxygen and hydrogen peroxide, as second oxidizers working synchronously with them in various media (aqueous, aqueous-organic and organic) with the participation of mineral and carboxylic acids close to room temperature. The contribution of the reactivity of the metal to its rate of consumption, especially the average, is often much less than the contribution associated with the release characteristics of the working surface, determined by the rates of accumulation of surface deposits of metal oxidation products, their strength and adhesion characteristics their destruction and shifting into the bulk phase.
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Date submitted2018-09-08
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Date accepted2018-10-27
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Date published2019-02-22
Special strategy of treatment of difficulty-profile conical screw surfaces of single-screw compressors working bodies
- Authors:
- A. S. Vasilev
- A. A. Goncharov
The article deals with the problems arising during the shaping of complex profile tapered helical surfaces. These surfaces form the geometry of the working bodies of single-screw miniature compressors, which have great prospects for use in mobile miniature compressor plants, which is especially important for medical and space technology, robotics, oil and gas and mining industries. Due to the fact that the capabilities of existing CAD systems do not allow obtaining three-dimensional models of these surfaces, the problem of preparing a control program for a CNC machine arises, since the calculation of the tool path in CAM systems when processing complex surfaces is impossible without a three-dimensional surface model. To solve the problem, an automated programming system was developed that implements a formalized toolpath calculation in accordance with the proposed special processing strategy for conical helical surfaces. As the initial data for calculating the toolpath, the system needs information about the tool geometry and the helical surface in a parametric form, which makes it possible to abandon the construction of a three-dimensional surface model. The results of processing prototypes for the proposed strategy are given.
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Date submitted2017-10-31
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Date accepted2018-01-01
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Date published2018-04-24
Peculiarities of formation and growth of nanodispersed intermetallic strengthening inclusions in rapidly-solidified alloys of Al–Mg–Zr–X-system
- Authors:
- D. I. Budelovskii
- S. Yu. Petrovich
- V. A. Lipin
The paper is devoted to the influence of the fourth element on the microstructure of the rapidly-solidified alloys of the Al–Mg–Zr-system. Alloys were additionally doped with high-melting-point metals Ti, Hf, W, and Nb. In the structure of all samples in the immediate area of the cooled surface, uniformly distributed intermetallic inclusions of several nanometers in size were detected. Such a structure can be represented as a dispersion-strengthened composite. A quantitative metallographic analysis was carried out to quantitatively describe the structure of the obtained particles of the cooled melt. The obtained rapidly-solidified alloys can be described as dispersion-strengthened composite materials with the aluminum-magnesium alloy matrix and the intermetallic particles strengthener. Depending on the alloying component, these particles differ in shape (spheres, plates, agglomerates) and in size (from 200 nm when alloying with Hf and W up to 1.2-1.5 μm with Ti and Nb alloying). The X-ray phase analysis (XPA) showed that in the studied alloys of the Al–5Mg–1.2Zr–(0.5÷2.0)X-system, high cooling rates of melts lead to the formation of new intermetallic compounds that are absent in equilibrium systems. The example of an alloy with hafnium additive shows that an increase in the content of the alloying component (from 0.5 to 2 % by mass) leads to an increase in the volume ratio of intermetallic inclusions (from 5 to 12.8 %). At the same time, their shape and average size remain unchanged. The additional alloying component will improve the mechanical characteristics of aluminum alloys by increasing the recrystallization threshold of a rapidly-solidified alloy.
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Date submitted2010-07-21
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Date accepted2010-09-08
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Date published2011-03-21
Calculation methodology of physical parameters of the artificial pillar barrier
- Authors:
- M. N. Adreev
The article is devoted to the calculation methodology of physical parameters of the artificial barrier pillar needed when developing underquarry deposits of kimberlitic pipes in difficult hydrogeological conditions.
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Date submitted2010-07-15
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Date accepted2010-09-26
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Date published2011-03-21
Development of the stowing material and testing of its mechanical properties
- Authors:
- M. N. Andreev
- E. I. Boguslavskiy
Article is in touch with analysis of backfill materials applied on diamond mines, description of research of its mechanical properties to create the optimal compound in conditions of Yakutian kimberlitic tubes.
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Date submitted2009-08-13
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Date accepted2009-10-29
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Date published2010-02-01
Analysis of statistical data of lecture of the alloyed steels
- Authors:
- R. V. Kurtenkov
Influence of a chemical compound on the carbon contents in a steel is analysed, in the course of processing of month basic data the mathematical model is received, it is offered optimum significances of source parametres at the carbon contents in a steel.