This article presents a study of Tomtor rare earth ore decomposition. This material contains a lot of valuable components such as REE and niobium (mas., %: 12,8 ΣREO (rare earth oxides), 0.039 Sc, ...18.4 P2O5, 9.9 Fe, 9.0 Al, 0.24 ThO2, 8.2 Nb2O5). The study aims to find efficient ways of processing this deposit. Technologies using the sulfuric acid as the main reagent to leach are described in this article. Investigation has three trends. The first trend is agitation leaching at low sulfuric acid concentrations, temperatures up to 95 °C and atmospheric pressure. The second trend is pressure leaching at low sulfuric acid concentrations, high temperatures (up to 180 °C) and high pressure. The third trend is high temperature sulfatization with concentrated sulfuric acid at elevated temperature (up to 180 °C) and atmospheric pressure followed by aqueous leaching. The dependence of target components (rare earth elements, scandium, phosphorus) and the impurity (iron, aluminum, thorium) extractions into solution from major factors was studied.
Unique magmatogenic putoranite ores are developed within deep horizons (more than 1750 m) of the northeastern flank of the Oktyabr’skoe deposit in the Norilsk ore field. These are coarse-grained ...putoranite aggregates with lamellae of moihoekite and isolated pentlandite disproportionation. The composition of putoranite is (Fe
17.6–17.9
Ni
0.4–1.1
Co
0–01
)
18–19
Cu
15.8–17.0
35
S
32
; the composition of moihoekite is (Fe
17.8–18.0
Ni
0.2–0.3
Co
0–01
)
18.2–18.3
Cu
17.7–17.8
36
S
32
; petlandite contains 1.75 wt % of Co, its composition is (Ni
4.41
Fe
4.36
Co
0.23
)
9
S
8
. The ores hold pneumatolytic stannopalladinite Pd
5
CuSn
2
, polyarite Pd(Bi,Pb), plumbopolyarite Pd(Pb,Bi), tetraferroplatinum Pt
2
Fe(Fe,Cu,Ni), tulameenite Pt
2
Fe(Cu,Fe,Ni), and küstelite (Ag,Au). Bornite is widespread in tectonized ores, as well as later aggregates of hibbingite and Mn-hibbingite (Fe
2+
, Mn
2+
)
2
(OH)
3
Cl, siderite, and Mn-siderite (Fe
2+
, Mn
2+
)CO
3
that replaced magnetite and Cu-Fe-Ni sulfides. Pure zvyagintsevite Pd
3
Pb and native silver compose syngenetic inclusions in hibbingite and siderite aggregates. Pure zvyagintsevite also replaces pneumatolytic polyarite and plumbopolyarite, the material of which was the probable source of generation of metamorphic-hydrothermal zvyagintsevite. This zvyagintsevite is sharply different from pneumatolytic zvyagintsevite in not having Pt, Sn, Bi, Sb, and Hg. Hypogene phosgenite Pb
2
Cl
2
/CO
3
detected for the first time composes pseudomorphs after galena, sometimes intergrown with hibbingite. Being new among the Norilsk ores, the described mineral low-temperature metamorphic-hydrothermal association originated in the presence of carbon dioxide-chloride solutions under reducing conditions. The later hisingerite, bornite, and barite that replaced hibbingite and siderite were formed at increased fugacity of oxygen.
The problem of copper leaching from copper-electrolyte slimes is discussed. To intensify the long and costly process, it is proposed to use a leaching system containing sulfuric acid and hydrogen ...peroxide as an oxidizing agent. The chemical transformations possible variants at the treatment of slime under the specified conditions and the thermodynamic parameters of the predicted reactions are considered. Solution composition effect on the copper dissolution rate at room temperature was studied in the presence of hydrogen peroxide using the rotating disc technique. It is found that dissolution rate constant at using hydrogen peroxide slightly inferior to dissolution rate constant under autoclaved conditions in an oxygen atmosphere.
The open-source scientific software packages OpenGeoSys and IPhreeqc have been coupled to set up and simulate thermo-hydro-mechanical-chemical coupled processes with simultaneous consideration of ...aqueous geochemical reactions faster and easier on high-performance computers. In combination with the elaborated and extendable chemical database of IPhreeqc, it will be possible to set up a wide range of multiphysics problems with numerous chemical reactions that are known to influence water quality in porous and fractured media. A flexible parallelization scheme using MPI (Message Passing Interface) grouping techniques has been implemented, which allows an optimized allocation of computer resources for the node-wise calculation of chemical reactions on the one hand and the underlying processes such as for groundwater flow or solute transport on the other. This technical paper presents the implementation, verification, and parallelization scheme of the coupling interface, and discusses its performance and precision.
Plasmadynamic processes and rapid shock-wave processes accompanying the generation of plasma formation in a supersonic jet flow are analyzed on the basis of high-speed digital recording of images. We ...analyze (with a high time resolution) the dynamics of spherical plasmoid formation, discontinuities generated by it, and their action on the bow shock wave in front of the model. It is shown that during the plasmoid lifetime (about 100–120 μs), the regime of the supersonic flow past the model is modified: the shock layer is rearranged, and the departure of the bow wave from the symmetry axis substantially increases due to a change in the structure and parameters of the incoming flow.
In the present work, gold electroextraction technological features on three-dimensional cathode are studied. Zinc powders are used as cathode. Similar ones are used to gold cementation from cyanide ...solutions. The studies object was production of cyanide solution of following composition, mg/dm3: 7 Au. 123.65 Zn, 670 CN-; pH 10.3. Electroextraction laboratory studies were carried out in cylindrical electrolyzer with a horizontal arrangement of current-carrying electrode. It has been found that zinc powders polarization contributes to more complete gold deposition from cyanide solutions. Moreover, it allows to reduce zinc transition into spent solution, as a consequence, zinc consumption reduces. At the same time, under investigated conditions, significant cyanide oxidation does not occur.
The present work relates to hydrometallurgy, in particular, to gold-bearing clay ores leaching processes. The initial and agglomerated material filterability was studied. Filterability varies in ...different agglomeration conditions. Influence of cement, lignosulfonate, plastizer (Cemmix CemPlast), lime consumption was investigated. The negative effect of organic reagents additives, such as plasticizer (Cemmix CemPlast) and lignosulfonate, on the filtration process was established. Colmatation of agglomerated ore minimizes at CaO and Ca (OH)2 using as a modifier of the system, also phase separation in the percolation regime and under pressure proceeds without difficulty. Lime and cement joint use in the optimum proportion at clay ore agglomeration under the studied conditions reduces the filtration duration from a few hours to 2-5 minutes.
The paper proposes an approach to the building of logical triggers in event-driven systems using relational interactive logic. In general, a trigger is viewed as a system of logical equations and ...inequalities. The solution of the system, carried out by the execution of a SQL query, is the main one for the formation of alert or targeted notifications or for changing the parameters of the control action within a specific system. To automate the described approach, an example of a modular scalable architecture of an information system is proposed. It provides the creation of triggers based on systems of logical equations and inequalities, as well as their verification of their implementation within one or more data domains
Future detection of extensive air showers (EAS) produced by ultra high energy cosmic particles by means of space-based fluorescence telescopes will open a new window on the universe and allow cosmic ...ray and neutrino astronomy at a level that is virtually impossible for ground based detectors. In the context of the extreme universe space observatory (EUSO) project, an end-to-end simulation of EAS observation with a spatial detector has been designed (EUSO simulation and analysis framework, ESAF). This paper describes the detailed Monte-Carlo developed to simulate all the physical processes involved in the fluorescence detection technique, from the EAS development to the instrument response. Particular emphasis is given to modeling the light propagation in the atmosphere and the effect of clouds. The simulation is used to assess the performances of EAS spatial detection. Main results on energy threshold and resolution, direction resolution and
X
max determination are reported. Results are based on EUSO telescope design, but are also extended to larger and more sensitive detectors.
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