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Date submitted2021-05-19
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Date accepted2022-04-07
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Date published2022-04-29
On the possibility of reducing man-made burden on benthic biotic communities when mining solid minerals using technical means of various designs
The paper analyses features of the species composition and diversity of biotic communities living within the ferromanganese nodule fields (the Clarion-Clipperton field), cobalt-manganese crusts (the Magellan Seamounts) and deep-sea polymetallic sulphides (the Ashadze-1, Ashadze-2, Logatchev and Krasnov fields) in the Russian exploration areas of the Pacific and Atlantic Oceans. Prospects of mining solid minerals of the world’s oceans with the least possible damage to the marine ecosystems are considered that cover formation of the sediment plumes and roiling of significant volumes of water as a result of collecting the minerals as well as conservation of the hydrothermal fauna and microbiota, including in the impact zone of high temperature hydrothermal vents. Different concepts and layout options for deep-water mining complexes (the Indian and Japanese concepts as well as those of the Nautilus Minerals and Saint Petersburg Mining University) are examined with respect to their operational efficiency. The main types of mechanisms that are part of the complexes are identified and assessed based on the defined priorities that include the ecological aspect, i.e. the impact on the seabed environment; manufacturing and operating costs; and specific energy consumption, i.e. the technical and economic indicators. The presented morphological analysis gave grounds to justify the layout of a deep-sea minerals collecting unit, i.e. a device with suction chambers and a grip arm walking gear, selected based on the environmental key priority. Pilot experimental studies of physical and mechanical properties of cobalt-manganese crust samples were performed through application of bilateral axial force using spherical balls (indenters) and producing a rock strength passport to assess further results of the experimental studies. Experimental destructive tests of the cobalt-manganese crust by impact and cutting were carried out to determine the impact load and axial cutting force required for implementation of the collecting system that uses a clamshell-type effector with a built-in impactor.
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Date submitted2020-05-21
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Date accepted2020-10-05
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Date published2020-11-24
Method of calculating pneumatic compensators for plunger pumps with submersible drive
- Authors:
- Eduard O. Timashev
One of the most promising ways to improve the efficiency of mechanized oil production is a plunger pump with a submersible drive, which allows obtaining harmonic reciprocating movement of the plunger. In the pumping process of well products by plunger pumps, oscillations in the velocity and pressure of the liquid in the lifting pipes occur, which lead to an increase in cyclic variable loads on the plunger, a decrease in the drive life period and the efficiency of the pumping unit. To eliminate the pulsation characteristics of the plunger pump and increase the reliability indicators of the pumping unit (in particular, the overhaul period), pneumatic compensators can be used. A method for calculating the optimal technological parameters of a system of deep pneumatic compensators for plunger pumping units with a submersible drive, based on mathematical modeling of hydrodynamic processes in pipes, has been developed. Calculations of the forming flow velocity and pressure in the lifting pipes of submersible plunger units equipped with pneumatic compensators (PC) have been carried out. Influence of the PC technological parameters on the efficiency of smoothing the oscillations of velocity and pressure in the pipes has been analyzed. Non-linear influence of the charging pressure and PC total volume on the efficiency of their work has been established. Optimal pressure of PC charging, corresponding to the minimum pressure in the tubing during the pumping cycle for the considered section of the tubing, is substantiated. Two ultimate options of PC system placement along the lifting pipes are considered. In the first option, PC are placed sequentially directly at the outlet of the plunger pump, in the second - evenly along the lift. It is shown that the first option provides the minimum amplitude of pressure oscillations at the lower end of the tubing and, accordingly, variable loads on the pump plunger. Nature of the pressure and flow velocity oscillations in the tubing at the wellhead for both options of PC placement has similar values .
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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 submitted2019-04-30
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Date accepted2019-07-16
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Date published2019-10-23
Salt Rock Deformation under Bulk Multiple-Stage Loading
- Authors:
- I. L. Pankov
- I. A. Morozov
The paper presents experimental justification of the possibility to use bulk multiple-stage loading to study the process of salt rock deformation in the laboratory conditions. Results of comparative tests between bulk multiple- stage and single-stage loading of salt rock samples are demonstrated. The paper contains results of research on the rate of lateral pressure and its impact on strength limit and residual strength limit of sylvinite, estimated using single- stage and multiple-stage methods. Research results demonstrate how the rate of lateral pressure impacts dilatancy boundary of salt rocks. Analysis of how the loading method influences certificate parameters of Mohr-Coulomb strength of sylvinite has been carried out. The dynamics of elastic modulus in the process of salt rock deformation is analyzed depending on the rate of lateralpressure. It is demonstrated how the method of multiple-stage loading adequately reflects the processes of salt rock de- formation and decomposition, and facilitates not only lowering impact of sample’s inner structure heterogeneities on the experimental results, but also significant reduction in the required amount of rock material.
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Date submitted2018-11-03
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Date accepted2019-01-16
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Date published2019-04-23
Interpretation of the tracer investigation results considering convective mass transfer
- Authors:
- V. A. Korotenko
- S. I. Grachev
- A. B. Kryakvin
The paper discusses the results of interpreting well tracer studies. It is shown that from the law of mass conservation it follows that when filtering a volume of an indicator, part of the injected tracer flows into the matrix. With the flow of fluid containing the indicator from the low-filtration resistance channel (LFR) into the surrounding matrix, the linear dimensions of the flow area depend on the permeability and porosity properties of the high-permeability channel and the matrix. While another part of the tracer moves toward the production well, its mass is lost due to diffusion processes. From the solution of the diffusion equation, it follows that the initial concentration of the tracer decreases in the course of filtration along the LFR channel. To interpret the results of the tracer studies, different cases of the LFR channels' location in the volume of the productive formation are considered. The varied parameter w allows characterizing the presence of several peaks in the concentration of the indicator and calculation the filtration parameters of the LFR channels. Depending on the known technological indices, several methods for determining pore volumes in the LFR channels have been proposed. To reduce the water cut in producing wells and to apply the technology of changing or aligning the injectivity profiles, calculations of the pore channels' radii in the mass of highly permeable seams are presented. It is shown that the volume of the chemical reagent pumped into the injection well to isolate the LFR channel is affected by the linear dimensions of the drainage area for the aqueous solution of indicator. Examples of the calculation for the permeability and porosity parameters of the LFR, the volume of pore channels necessary to isolate water inflow, and the radii of pore filtration channels, which influence the selection of the size of chemical reagent molecules, are given.
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Date submitted2010-07-14
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Date accepted2010-09-07
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Date published2011-03-21
Substantiation of pumped volumes of flow angularity compositions in injection wells
- Authors:
- A. R. Mavliev
- M. K. Rogachev
- D. V. Mardashov
The method of calculation pumped volumes of flow angularity compositions in injection wells, which based on combination of the seepage theory, laboratory investigation and field experience is developed.
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Date submitted2009-10-26
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Date accepted2009-12-27
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Date published2010-09-22
Support of geodynamic safety in mining of the Khibini deposits
The paper deals with the problems of geodynamics in mining of the Khibini deposits. Description is given to the complex of organizational-technical arrangements for provision of geodynamic safety at the Apatit Co and to principal trends of its development.
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Date submitted2009-10-21
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Date accepted2009-12-26
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Date published2010-09-22
Modeling of geomechanical processes in mining the steeply pitching ore bodies of rockburst-hazardous deposits
The article contains the results of numerical modeling of stress-strain state in constructive elements of mining systems, applied at hazardous and prone to rook bursts deposits of the Far-East. Consideration is given to some stated regularities of forming of teсhnogenic stress field and geomechanical processes proceeding in rock mass of minable deposits which allow to substantiate a сomplex of measures for prevention of dynamic rock pressure manifestations.
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Date submitted2009-07-25
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Date accepted2009-09-13
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Date published2010-04-22
Specific behaviour of prefabricated tunnel linings
- Authors:
- E. A. Karasev
Analysis of different methods to model prefabricated tunnel lining is done. The description of main advantages and disadvantages of existing method is given. Method of detailing stress state prediction of prefabricated lining based on 3d finite elements method with complicated interaction between lining segment and soil is proposed.
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Date submitted2009-07-29
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Date accepted2009-09-29
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Date published2010-04-22
State examination of mineral reserves in the system of wise utilization of the earth’s interior
- Authors:
- Yu. A. Podturkin
The major problem of bodies of the government in sphere of regulation of attitudes protection of reserves creation of conditions for rational use of resources. The basic role in its decision is played with examination protection of reserves. Maintenance of effective carrying out of examination demands its constant perfection with reference to market conditions with use of the international criteria regarding both calculation and an estimation of stocks, and drawing up design and the engineering specifications on development of mineral deposits.
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Date submitted2009-07-12
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Date accepted2009-09-08
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Date published2010-04-22
Account and movement of reserves in the information system of Silvinit co.
- Authors:
- A. V. Kataev
- S. N. Kutovoi
- E. M. Efimov
- M. V. Gilev
At ore mines of the Silvinit Co. for accounting and movement of reserves are developed and used special tools, using GIS within the information system. Their use allows to automate accounting and monitoring of status and movement of stocks, including the formation of the reporting tables.
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Date submitted2008-10-07
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Date accepted2008-12-05
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Date published2009-12-11
The application of areal technology and 3d data interpretation tem sounding when constructing the volume geoelectrical model of compound medium
Analysis of possibilities of different electrical technologies is carried out. Problems of applications of one-dimension and multidimensional inversions in the process of interpretation are discussed. Example of practical application of two- and three-dimension interpretation of electrical data in the process of ore prospecting in complicated geological media is presented. The example illustrates possibilities of electrical method as original research method, which enables to develop three-dimensional models of the medium under investigation.