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Date submitted2005-09-21
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Date accepted2005-10-01
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Date published2006-04-01
Commonwealth of metallurgists and chemists of Mining Institute over 230 years
- Authors:
- D. E. Chirkst
The history of the formation of the departments of the metallurgical faculty and chemical-metallurgical school of the Mining Institute is presented. A brief review of the main stages of development of metallurgical and chemical sciences is given. The main achievements in the field of metallurgy and chemistry, which served as a basis for the modern scientific schools of the metallurgical faculty, are shown.
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Date submitted2005-09-25
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Date accepted2005-10-29
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Date published2006-04-01
State, problems and prospects of development of the method of complex processing of nepheline
- Authors:
- V. M. Sizyakov
The main directions of improvement of complex processing of nepheline for alumina and passive products are considered. The estimation of promising "dry" method of alumina and portland cement production, problems of aluminum and silicon separation and obtaining coarse-grained alumina of higher qualities, the prospect of expanding the range of products is shown, the comparative analysis of cost characteristics of apatite and nepheline concentrates is given, indicating a higher potential of nepheline raw materials.
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Date submitted2005-09-29
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Date accepted2005-10-24
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Date published2006-04-01
Development of technology of coarse-grained alumina production in industrial conditions
Industrial tests on the improvement of coarse-grained alumina at the PAR-SUAL Branch are conducted during the period of stable operation of the enterprise. Hydrate hydro classification was included in the apparatus-technological scheme of aluminate solutions processing on special hydro classifiers (HC) of VAMI design. The unbalanced part of fine fractions was eliminated in production.
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Date submitted2005-09-12
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Date accepted2005-10-30
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Date published2006-04-01
Optimization of processes of preparation of nepheline-limestone charge on the basis of advance grinding of nepheline component
The issues of optimization of nepheline-limestone charge preparation processes based on the principle of independence of grindability of individual components are considered. Recommendations are given for improving the efficiency of grinding equipment at the PAR-SUAL Branch.
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Date submitted2005-09-01
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Date accepted2005-10-19
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Date published2006-04-01
Influence of dispersibility of nepheline and limestone on quality of aluminum sinter
- Authors:
- V. M. Sizyakov
The influence of nepheline and limestone dispersibility in nepheline-limestone charge on the quality of aluminate sinter is considered, the optimum ratio of the size of these components is revealed.
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Date submitted2005-09-27
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Date accepted2005-10-02
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Date published2006-04-01
Studies of Mining Institute in the field of titanium and refractory compounds production
- Authors:
- S. V. Aleksandrovskii
The staff of the Leningrad Mining Institute - St. Petersburg State Mining Institute (Technical University) together with the specialists of other research organizations (VAMI, Institute of Titanium, Giredmet), where LMI graduates worked, laid the foundations for successful development of modern production of sponge titanium at titanium-magnesium plants of the former Soviet Union. Simultaneously with the creation of industrial production of titanium sponge, the staff of the Mining Institute successfully worked on science-intensive technologies aimed at the development of original methods of production of refractory metals and their compounds: high-quality powders of titanium, zirconium, scandium, homogeneous ligatures, carbides, fullerenes, composite materials. The developed technologies of metal-thermal processes are based on the use of man-made products and industrial equipment of titanium-magnesium production.
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Date submitted2005-09-14
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Date accepted2005-10-14
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Date published2006-04-01
Preparation of zirconium-containing materials on the basis of eudialyte concentrate
The technology of obtaining zirconium oxide, zirconium halide compounds (chlorides, fluorides) from eudialyte concentrate with subsequent production of zirconium powders, titanium-zirconium and aluminum-zirconium ligatures by metal-thermal method has been investigated. It is shown that different zirconium materials can be obtained by applying different reducing agents: sodium, magnesium or aluminum-magnesium alloys.
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Date submitted2005-09-18
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Date accepted2005-10-03
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Date published2006-04-01
Nitric-acid leaching of copper-electrolyte sludge
The processes occurring at nitric acid leaching of copper-electrolyte slimes are described. The influence of firing temperature and concentration of nitric acid on the degree of transition of silver and related elements into solution is investigated. Optimal modes providing high extraction of silver into solution and concentration of gold in the insoluble residue have been established.
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Date submitted2005-09-16
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Date accepted2005-10-05
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Date published2006-04-01
Ways to Improve the Quality of Technical Tellurium
Methods of refining of tellurium of technical purity have been developed and introduced. Due to application of oxidative smelting and distillation industrial batches of tellurium were obtained, in which the content of guest impurities meets semiconductor grades.
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Date submitted2005-09-26
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Date accepted2005-10-12
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Date published2006-04-01
Study of distribution of time of stay of firing products in fluidized bed furnace
Regularities of particle residence time distribution in the pilot fluidized bed furnace with return cyclones are investigated. The parameters of curve functions of particle residence time distribution at the furnace outlet for cinders and dust at the outlet from the return cyclone were determined: average residence time, dispersion and number of cells in the cell model. It is established that the flow structure in the studied fluidized bed furnace is close to the model of ideal mixing.
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Date submitted2005-09-24
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Date accepted2005-10-18
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Date published2006-04-01
Study of the material composition of copper-nickel sulphide raw materials
To establish the physicochemical nature of phases in matte and matte, it is necessary to consider binary systems Cu-S, Ni-S, Fe-S, because the structural components in these systems can serve as phases in matte and matte, as well as be the beginning of the formation of new phases in them.
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Date submitted2005-09-10
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Date accepted2005-10-21
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Date published2006-04-01
Application of interval-simplex method for description of chemical reactions kinetics
An interval-simplex method of transforming kinetic equations of various degrees of complexity into a form convenient for practical engineering calculations to determine the parameters included in these equations is considered. This method allows to transform kinetic equations into a dimensionless form using simplex similarity. Representations of the interval-simplex method for transformation of equations describing regularities of kinetics of heterogeneous and homogeneous chemical processes of dissolution, leaching, as well as complex autoclave processes are considered.
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Date submitted2005-09-06
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Date accepted2005-10-22
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Date published2006-04-01
Use of organic reducing agents in hydrometallurgical processing of oxide manganese-containing materials
The issues of chemical sulfuric-acid leaching of oxide manganese-containing raw materials in the presence of reducing agents for the purpose of further obtaining high-quality dephosphorus concentrates are considered. The efficiency of using organic acids and alcohols as reducing agents is shown.
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Date submitted2005-09-02
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Date accepted2005-10-16
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Date published2006-04-01
Model of technology of limestone roasting in a shaft kiln
The mathematical description of the technology of firing of lump limestone raw materials in a shaft kiln equipped with burner devices providing preliminary gas combustion is given. The model takes into account the peculiarities of the process of dissociation of carbonate component of raw materials, uses equations describing the kinetics of the drying process, conditions of counter-flow of gases and material, regularities of distribution of material and gas flows along the cross-section and height of the shaft. The developed model represents a stationary two-dimensional solution of the problem.
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Date submitted2005-09-22
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Date accepted2005-10-15
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Date published2006-04-01
Low-temperature desiliconization of aluminate solutions on activated inoculants
- Authors:
- V. N. Brichkin
- E. V. Sizyakova
- R. S. Gordeev
The paper describes the theory and practice of low-temperature decomposition of alumina solutions. Scientific substantiation of the use of activated nepheline solution as an inoculum for HASN crystallization is given. Materials of experimental study of chemical equilibrium and kinetics of the decomposition process in the system activated nepheline alcohol - aluminate solution are presented. The possibility of achieving technological low-temperature factors of the process sufficient for the subsequent complete deposition of silica is shown.
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Date submitted2005-09-13
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Date accepted2005-10-25
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Date published2006-04-01
Thermodynamic bases of recrystallization of alumina production precipitates with participation of gas phase
- Authors:
- V. N. Brichkin
- A. V. Tsybizov
- R. S. Gordeev
Materials explaining the mechanism of spatial differentiation of solution composition with the participation of the gas phase and its role in the creation of non-equilibrium conditions that ensure recrystallization of solid products are presented. Calculations of equilibrium in a number of systems of alumina production are presented. Indicators of non-equilibrium of solutions and their dependence on the leading technological parameters of the process are established.
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Date submitted2005-09-30
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Date accepted2005-10-18
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Date published2006-04-01
Elementary processes in precipitation of aluminum hydroxide
- Authors:
- V. N. Brichkin
- A. V. Tsybizov
- R. S. Gordeev
The mechanism of mass crystallization of synthetic gibbsite at decomposition of aluminate solutions is proposed. The leading role of nucleation and supersaturation in the formation of granulometry of aluminum hydroxide precipitate is shown. The methodology and experimental results of induction period determination during gibbsite precipitation from aluminate solution are presented. The surface energy of solid phase formation during carbonization of aluminate solution as a function of critical nucleation size is determined.
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Date submitted2005-09-18
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Date accepted2005-10-18
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Date published2006-04-01
The analysis of studying the phenomenon of segregation process
- Authors:
- A. M. Vasilev
The article gives a review of research on the segregation process. Specific examples of apparatuses on which segregation is manifested are given. The role of stratification on segregation processes in gravity enrichment methods is identified, traced and substantiated.
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Date submitted2005-09-01
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Date accepted2005-10-03
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Date published2006-04-01
Theoretical aspects of the phenomenon of intra-layer segregation
- Authors:
- A. M. Vasilev
The main theoretical approaches of the segregation process are considered. The necessity of further study of the segregation process is emphasized, which will allow to create a new highly efficient and productive separator.
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Date submitted2005-09-08
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Date accepted2005-10-22
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Date published2006-04-01
Research on the influence of water viscosity factors and segregation phenomenon on mineral beneficiation indicators
- Authors:
- A. M. Vasilev
The method of studying the segregation phenomenon and the quantitative data obtained with its help are considered. The influence of water viscosity on mineral processing performance from different points of view: theoretical and experimental. After analyzing the relevant literature, the choice of formula is made and the calculation is carried out according to it, which showed the differences in the average flow velocities of water movement along the helical surface. In the experimental part, experiments were carried out on the screw sluice VSH-350.
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Date submitted2005-09-08
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Date accepted2005-10-11
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Date published2006-04-01
Research of metallurgical limestone roasting process in a shaft kiln
- Authors:
- V. O. Golubev
The results of numerical studies of aerodynamics of the dense layer and hollow regions of the shaft kiln; mechanism of material movement; kinetics of lump limestone dissociation are presented. A mathematical model of a shaft kiln with distributed parameters is developed. A computer program allowing to carry out predictive calculations of firing and to optimize mode and determining geometrical parameters of the installation is made. Proposals for modernization of operating shaft furnaces are made.
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Date submitted2005-09-15
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Date accepted2005-10-16
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Date published2006-04-01
Mathematical model of dissociation of single granule of calcium carbonate
- Authors:
- V. O. Golubev
- I. N. Beloglazov
A numerical approach to solving the problem of dissociation of natural calcium carbonate represented by a piece of limestone or chalk having a spherical shape is considered. The modeling takes into account the mutual influence of thermal and mass transfer factors, as well as thermochemical kinetics of the dissociation process.
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Date submitted2005-09-21
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Date accepted2005-10-20
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Date published2006-04-01
Method of dissolution of copper-nickel anodes containing noble metals
The article reflects the main aspects of determining the dissolution potentials of copper- and nickel-based alloys containing precious metals in laboratory conditions and the choice of electrolyte for their dissolution. The composition of the investigated anode, graphs of dependence of the obtained potentials on time and voltage are given. The influence of some impurities on the process is explained. The conclusion about the rationality of using hydrochloric acid electrolyte is made.
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Date submitted2005-09-01
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Date accepted2005-10-18
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Date published2006-04-01
Application of center-run extractors in petrochemistry
One of the ways of recovery of metals from oil is considered. It is proposed to carry out the extraction of metals from oils using a separator with centrifugal phase separation. This type of separators can be used not only for extraction of valuable components such as metals from oils, but also for purification of water from oil products, as well as for hydrometallurgical production of non-ferrous metals.
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Date submitted2005-09-30
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Date accepted2005-10-30
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Date published2006-04-01
Investigation of possibility of processing of phosphorus-containing ferromanganese nodules of the Gulf of Finland
- Authors:
- A. A. Darin
- N. M. Telyakov
Thermodynamic and experimental substantiation of the possibility of selective separation of manganese and phosphorus by neutral leaching after preliminary sulfuring burning for iron-manganese concretions (IMC) of different compositions is provided.
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Date submitted2005-09-28
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Date accepted2005-10-07
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Date published2006-04-01
Energy-saving technology of deep-rocked alumina production
- Authors:
- O. A. Dubovikov
A new energy-saving technology for the production of dead-burnt alumina has been studied, which differs from the existing ones in that the introduction of boric acid mineralizer simultaneously neutralizes the residual content of alkali. This makes it possible to carry out roasting in one stage. A method of chemical control over the content of α-modification of aluminum oxide during calcination of alumina has been proposed and tested. The method allows to monitor not only the quality of the obtained product, but also to quantify the content of corundum in alumina. The experimental results were confirmed by crystal-optical and X-ray diffraction studies.
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Date submitted2005-09-21
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Date accepted2005-10-04
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Date published2006-04-01
Investigation of copper behavior during tellurium precipitation from sulfide-alkaline solutions
- Authors:
- Yu. A. Zaitsev
- V. A. Ivanov
The research is devoted to the possibility of copper transition into sulfide-alkaline tellurium solutions using radioactive isotopes of copper and tellurium. The authors studied the possibilities of purification of such solutions from copper, proposed a method of copper splitting as a product of processing. Application of this method to industrial solutions makes it possible to obtain tellurium containing millionths of copper, which ensures compliance with T-1 grade.
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Date submitted2005-09-17
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Date accepted2005-10-30
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Date published2006-04-01
Application of press filters at the stage of copper-nickel concentrates dehydration
The paper describes the operation and control system of modern press filters on the example of LaroxPF filters installed in the roasting shop of Pechenganickel Combine. The main problems of improving and optimizing the operation of press filters are identified and a method of their solution is proposed by drawing up regression dependencies for the main characteristics of filter operation based on experimental data.
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Date submitted2005-09-24
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Date accepted2005-10-17
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Date published2006-04-01
Improvement of designs of devices for combustion of natural gases of different composition
- Authors:
- P. V. Ivanov
- Yu. V. Sharikov
The article focuses on research aimed at improving fuel combustion devices, processing of gaseous energy carrier to ensure volumetric combustion by preliminary mixing of energy carrier with air and giving the burning fractions buoyancy by mineral additives due to adhesion and increasing their efficiency and reducing environmental pollution.
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Date submitted2005-09-08
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Date accepted2005-10-24
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Date published2006-04-01
Logometric method of analyzing the composition of suspensions
- Authors:
- D. S. Kireev
- I. N. Beloglazov
- S.Z. El-Salim
This report considers the problem of analyzing the concentration of suspended particles in dispersed media and the concentration of components in regular solutions. The logometric method recommended by the Metallurgical Faculty of the St. Petersburg Mining Institute allows to solve this problem and increase the efficiency of process control in the mining and metallurgical industry without complicating the analytical system.
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Date submitted2005-09-25
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Date accepted2005-10-10
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Date published2006-04-01
Intensification of sorption purification by alternating electric field
- Authors:
- D. S. Kireev
- A. A. Chistyakov
- S.Z. El-Salim
The article describes the theoretical basis of the high-frequency effect of increasing the mobility of ions in aqueous solutions under the action of an electric field and the possibilities of adapting this effect to the sorption treatment of wastewater and technical solutions.
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Date submitted2005-09-14
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Date accepted2005-10-05
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Date published2006-04-01
Estimation of error of information channels of control systems
The article describes the signal paths of modern control systems. The method of error accumulation to the signal is shown, an example of calculation of such an error is given. Some variants of solving the problem of reducing this error are offered.
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Date submitted2005-09-22
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Date accepted2005-10-27
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Date published2006-04-01
Neural network technologies in control system of melting process in Vanyukov furnace
The article describes the possibilities of application of neural network technologies in the control system of the melting process in the furnace. The variants of using neural networks both in local control loops and in the control system of the whole process are shown. Advantages and disadvantages of such systems are considered. The example of creation of the simplest neural network regulator for stabilization of parameters is given.
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Date submitted2005-09-27
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Date accepted2005-10-26
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Date published2006-04-01
Briquetting of dusts containing non-ferrous metals
- Authors:
- L. A. Lenev
The article describes a method of briquetting dusts containing non-ferrous metals. The proposed method is aimed at solving the environmental problem of mining and metallurgical enterprises and allows to take valuable components additionally. In experiments the influence of additive, humidity and pressing pressure on the strength of briquettes is investigated.
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Date submitted2005-09-26
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Date accepted2005-10-18
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Date published2006-04-01
Influence of technology of coal briquettes manufacturing on their properties
- Authors:
- L. A. Lenev
- V. B. Kuskov
Environmental tension in coal-mining regions of the country is largely determined by the high level of coal production waste. And a significant part of waste is represented by fine fraction 0-3mm of coals, formed in the process of mining, during preparation, transportation, storage, etc. It is difficult to reduce the level of coal losses in the form of slimes and fines by direct combustion due to the complexity of loading and transportation, as well as the combustion process itself. Therefore, this product must be pelletized. The most accessible, studied and technically prepared method of coal fines pelletizing is the briquetting method. Experiments on briquetting of coal fines with the use of clay and starch as binding materials have been carried out.
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Date submitted2005-09-18
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Date accepted2005-10-11
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Date published2006-04-01
Study of regularities of briquetting of rich iron ore without binder additives
- Authors:
- L. A. Lenev
- V. B. Kuskov
The results of briquetting of rich iron ore without binder additives are presented. The dependencies that can be used in briquetting with binder additives are established. The influence of ore particle size distribution, moisture content, pressing pressure, and additives of different size classes on the strength properties of briquettes is studied.
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Date submitted2005-09-12
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Date accepted2005-10-01
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Date published2006-04-01
About possibility of iron oxide pigments production for paint and varnish industry
- Authors:
- L. A. Lenev
- V. B. Kuskov
- O. N. Tikhonov
Currently, almost all iron oxide pigments production is located in the neighboring countries. Besides, the used technologies of pigments production are environmentally harmful. Development of ecologically safe technology for obtaining pigment grade ore is a priority and quite actual task for the paint and varnish industry of Russia.
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Date submitted2005-09-04
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Date accepted2005-10-02
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Date published2006-04-01
Flotation extraction of nickel ions from dilute aqueous solutions
- Authors:
- O. L. Lobacheva
The possibilities of adsorption-bubble method - flotation extraction to reduce the concentration of nickel ions to the maximum permissible concentration have been determined experimentally. The obtained data testify to the efficiency of nickel ions extraction with the help of sodium dodecyl sulfate.
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Date submitted2005-09-16
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Date accepted2005-10-04
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Date published2006-04-01
Kinetics of iron (II)oxidation to iron (III)in sulfate solution by manganese ore
- Authors:
- A. K. Orlov
The study of kinetics of Fe(II) oxidation to Fe(III) by manganese ore at the content in the initial sulfate solution of 2g/dm 3 Fe(II), 14g/dm 3 H 2 SO 4 and temperature 17-18°C, oxidant consumption 100-250% of the theoretical one and different mode of its loading was established, that in the total reaction 2FeSO 4 +MnO 2 +2H 2 SO 4 =Fe 2 (SO 4 ) 3 +MnSO 4 +2H 2 O the first stage limiting the speed of the whole process is the interaction of MnO2 with sulfuric acid with the formation of MnSO4 passing into solution and active (atomic) oxygen, oxidizing then vigorously FeSO4 to Fe 2 (SO 4 ) 3 .
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Date submitted2005-09-07
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Date accepted2005-10-16
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Date published2006-04-01
Stage of sulfide oxidation during oxidative roasting of poly-mineral sulfide concentrates
- Authors:
- A. K. Orlov
The study of the kinetics of oxidative roasting of zinc concentrate and copper-zinc intermediate product at 400-900°C on a laboratory unit in a fluidized bed reactor showed that at temperatures up to 550-600°C there is practically oxidation of iron sulfides only, and at temperatures above 600°C there is a joint oxidation of all metal sulfides present in these concentrates.
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Date submitted2005-09-14
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Date accepted2005-10-08
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Date published2006-04-01
Improvement of melting technology of nickel and copper sludge cakes in metallurgical shop of copper plant of MMC Norilsk Nickel
- Authors:
- D. A. Pavlyuk
MMC Norilsk Nickel uses the process of drying coke cuprum-pyrite sludge and nickel sludge on secondary anodes to produce platinum metal concentrates. The process is characterized by high temperature, low stability of lining (furnace working cycle-7 days) and significant emission of powder and gas mixture. In laboratory conditions a structural loading has been developed, which allows to reduce the process confusion temperature by 200-250°C. To achieve this result, it is proposed to carry out technological mixing with the formation of slags, which are between silicate and bisilicate by acidity. The slags are characterized by low mixing temperature and viscosity, which provides reduction of losses with them of platinum metals.
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Date submitted2005-09-22
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Date accepted2005-10-18
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Date published2006-04-01
Investigation of silver selenide behavior in aqueous solutions
- Authors:
- G. V. Petrov
- A. M. Belenkii
- A. Ya. Boduen
The behavior of silver selenide in the whole range of pH values has been studied using thermodynamic calculations and polarization measurements. Pourbae diagrams at temperatures of 25 and 80°C have been constructed. The forms of selenium in acidic and alkaline solutions were determined.
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Date submitted2005-09-06
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Date accepted2005-10-09
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Date published2006-04-01
Study of chromite platinum-metal massifs of Russia
This type of deposits is the main exploration target for Pt, Ir, Os, Ru. Inferred resources of platinum group elements (PGM) from Ray-Iz are estimated at several tons. Methods of separation of rich concentrates of platinum metals by mechanical enrichment have been studied. Hydrometallurgical technology of PGM concentrates extraction from chromite ores is recommended. The expediency of PGM precipitation during processing of chromite materials at chemical plants even at low PGM content is shown. The prospectivity of chromite ores of the Polar Urals as a source of PGMs is substantiated.
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Date submitted2005-09-24
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Date accepted2005-10-21
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Date published2006-04-01
About the role of calcium hydrocarbon aluminates in improvement of technology of alumina production from nepheline
- Authors:
- E. V. Sizyakova
The data allowing to reveal the most effective solutions for the production of new by-products in the complex processing of nepheline have been obtained. It is shown that calcium hydrocarbon aluminates synthesized under conditions of alumina production play the main role in the technology of new materials: carbon sulfoaluminate-type mineralizers, rapid hardening cements of the "Rapid" type, high alumina cements, foundry cements. The main technical characteristics of new pro-ducts are given.
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Date submitted2005-09-13
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Date accepted2005-10-16
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Date published2006-04-01
Expansion of assortment of output products at complex processing of nepheline on the basis of use of calcium hydrocarbon aluminates
- Authors:
- E. V. Sizyakova
The study was carried out in order to find technological conditions that allow anodic dissolution of metal concentrate of radio-electronic scrap without difficulties caused by anode passivation. The thermodynamic probability of sufficiently complete oxidation of impurities included in the metal concentrate was established. The composition of refining slag allowing to bind oxidized impurities in slag is selected. Time dependence of oxidation of impurities by air due to application of radial-axial tuyere is shown. It is indicated that for 15min of blowing it is possible to prepare the metal-concentrate alloy for successful anodic dissolution in sulfuric acid electrolyte.
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Date submitted2005-09-22
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Date accepted2005-10-16
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Date published2006-04-01
Processes of oxidation of impurities of metal concentrate of radio-electronic scrap
- Authors:
- A. N. Telyakov
The study was carried out in order to find technological conditions that allow anodic dissolution of metal concentrate of radio-electronic scrap without difficulties caused by anode passivation. The thermodynamic probability of sufficiently complete oxidation of impurities included in the metal concentrate was established. The composition of refining slag allowing to bind oxidized impurities in slag is selected. Time dependence of oxidation of impurities by air due to application of radial-axial tuyere is shown. It is indicated that for 15min of blowing it is possible to prepare the metal-concentrate alloy for successful anodic dissolution in sulfuric acid electrolyte.
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Date submitted2005-09-09
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Date accepted2005-10-02
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Date published2006-04-01
Results of testing of technology of processing of radio-electronic scrap
- Authors:
- A. N. Telyakov
- L. V. Ikonin
The results of industrial processing of waste containing precious metals at the stages of disassembly, sorting and enrichment of radio-electronic scrap, melting and electrolysis carried out in industrial conditions of the operating enterprise are presented.
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Date submitted2005-09-10
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Date accepted2005-10-23
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Date published2006-04-01
Extraction of cerium(III) and yttrium(III) by carboxylic acids from nitrate media
Experimental data on the solvate extraction of cerium(III) and yttrium(III) by solutions of oleic and naphthenic acids in o-dimethylbenzene were obtained. After mathematical analysis of the dependences of the distribution coefficient on pH and the composition of the organic and aqueous phases, the structure and composition of the solvate complexes were determined, as well as the values of Gibbs free energies and equilibrium constants of the reaction.
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Date submitted2005-09-24
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Date accepted2005-10-18
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Date published2006-04-01
Extraction of cerium(III) and yttrium(III) by naphthenic acid from chloride media
Data on the extraction of cerium(III) and yttrium(III) by naphthenic acid solution in o-xylene from chloride media were obtained. The experiment showed W-shaped dependence of the distribution coefficient of cerium(III) and yttrium(III) on the Cl content in the equilibrium aqueous phase. The minima of the dependence are explained by the formation of non-extractable complexes MeCl 2 +and MeOH 2 +, the maxima - by the increase in the degree of dissociation of naphthenic acid and the increase in the ionic strength of the solution.
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Date submitted2005-09-27
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Date accepted2005-10-21
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Date published2006-04-01
Kinetics of iron(II) sorption by inorganic sorbent-iron-manganese nodules
Kinetic characteristics of the process of iron(II) sorption by ferromanganese nodules have been found: reaction rate constants at different temperatures, apparent activation energy of the process. The limiting stage of the process, which is a redox reaction of the first order, was determined.
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Date submitted2005-09-04
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Date accepted2005-10-20
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Date published2006-04-01
Investigation of kinetics of sorption of nickel cations by pyrolusite-containing sorbent
Kinetic characteristics of the process of nickel cations sorption by ferromanganese nodules were determined: reaction rate constants at different temperatures, apparent activation energy of the process.
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Date submitted2005-09-27
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Date accepted2005-10-08
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Date published2006-04-01
Thermodynamic calculation of solubility of rare earth metal phosphates at different temperatures and concentrations of ortho-phosphoric acid
- Authors:
- D. E. Chirkst
- O. V. Cheremisina
The thermodynamic calculation of oxygen solubility and ionic standing in solutions of cerium(III) phosphate acids allowed us to estimate the ionic composition of solutions and describe the course of crystallization and dilution processes of SePO 4 -0.5H 2 O, as well as to determine the dependence of oxygen solubility on temperature and concentration of solutions.
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Date submitted2005-09-04
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Date accepted2005-10-07
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Date published2006-04-01
Solubility of cerium(III) phosphate at different temperatures and concentrations of ortho-phosphoric acid
- Authors:
- D. E. Chirkst
- O. V. Cheremisina
The thermodynamic calculation of solubility and ionic equilibria in phosphoric acid solutions of cerium(III) allowed us to estimate the ionic composition of solutions, describe the mechanism of crystallization and dissolution processes СеРО 4 ·0.5H 2 O, determine the dependence of solubility on temperature and concentration of solutions.
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Date submitted2005-09-27
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Date accepted2005-10-10
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Date published2006-04-01
Conditions of blast feeding into melts and development of means of intensification of blast mode
The solubility of cerium (III) phosphate in the system CePО40,5H2O - solutions of ex-traction phosphoric acids (EPC) and in the system СеРО 4 ·0.5H 2 O - model solutions of H3PO4 depending on temperature and concentration of orthophosphoric acid has been studied. The values of solubility index pS from the pH value of the solution were found.