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Date submitted2023-07-20
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Date accepted2023-10-25
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Date published2024-04-25
Directions in the technological development of aluminium pots
- Authors:
- Еvgenii S. Gorlanov
- Leopold I. Leontev
Directions for the technical and technological development of aluminium industry, existing and promising projects to reduce the energy consumption and the environmental impact are analyzed. The active participation of the state in the organization of financial instruments for the ecological reconstruction of obsolete production facilities is discussed. In spite of the fact that the technology of aluminium pots is developed towards the increase of a single capacity, but with limited potential of reducing energy consumption and greenhouse gases emission, the possibilities for the increase of specific output are practically non-existent. Therefore, such projects like pots, equipped with inert anodes and drained cathodes arise and are under development, the successful completion of which is unlikely after multi-year researches and pilot tests. To continue the works related to inert anodes the decisive answer about the industrial safety of local sources of the massive oxygen emissions to atmosphere is required from competent entities. The drained cathode project, after discussing the existing problems, seems unfeasible. As opposed to the existing technology the development of the pots with vertical electrodes offers great opportunities to the designs of inert anodes and drained cathodes. Positive results of using shaped electrodes, homogenizing their surface and developing the methods for the synthesis of composite cathodes directly during the electrolytic process were obtained in laboratory conditions. It is expected that the combination of these trends and the successive dimensional scaling shall allow using the vertical electrodes at the next level for the fold increase of specific pot capacity and for the decrease of energy consumption and greenhouse gas emissions.
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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 submitted2015-07-27
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Date accepted2015-09-17
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Date published2016-02-24
Electroextraction of cobalt from sulfate-chloride and sulfate solutions of cobalt and manganese in static conditions
- Authors:
- L. P. Khomenko
- L. A. Voropanova
The dependence of the results of electroextraction cobalt and manganese from aqueous solutions of their sulphate and chloride-sulfate solutions under static conditions was investigated. According to the results of current efficiency and specific energy consumption it has been found that the electrowinning of cobalt from aqueous solutions of cobalt and manganese in static conditions using a titanium cathode should be carried out at low concentration of manganese from sulphate-chloride solution without partitions and from sulphate solutions both without and with the perforated partitions separating the electrolytic cell into cathode and anode space.
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Date submitted2009-09-06
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Date accepted2009-11-10
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Date published2010-06-25
Diagnostic method for measurements of emission parameters of thermoemission cathodes
- Authors:
- A. S. Mustafaev
This article deals with the diagnostic method of emission parameters of thermo emission cathodes by the transverse magnetic field. The knudsen Cs-Ba-diode with the surface ionization are investigated.
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Date submitted2009-09-26
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Date accepted2009-11-21
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Date published2010-06-25
The measurements of emission parameters of tungsten thermo cathodes in plasma energetic equipments
Emission parameters and coefficients of reflection of heat electrons from tungsten thermo cathodes were investigated under nontraditional for emission electronic conditions, when the surface contacts with highly ionized plasma. For measurements plasma diode electron current-magnetic field strength relations were used. Parameter Dj, which characterizes cathode heterogeneity by work function, and coefficient of reflection for policrystallic tungsten and for face 110 tungsten single crystal were measured. Proportion entering in effective reflection coefficient of electrons, reflected immediately from the surface and from potential barrier of spots field was determinate.
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Date submitted2009-08-25
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Date accepted2009-10-25
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Date published2010-02-01
The phenomenon of spontaneous termination of the discharge current and the establishment of fully-managed key elements of the plasma
For the first time magnetic and probe technique for diagnostics of anisotropic plasma have been worked out. Contemporary digital measuring methods, plasma plants and new generation devices of plasma energetics as well as special mathematical programs for fundamental investigations of anisotropic plasma were created. The inventions of Saint Petersburg Mining Institute are used for solving of plasma energetic problems.