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The thermal treatment of gypsum in boiling 1M, 2M, 3M, 4M and 4,5M solutions of magnesium chloride, at atmospheric pressure, in order to obtain α-CaSO 4 -0,5H 2 O was performed. Three mechanism of α-hemihydrate formation were identified... more
The thermal treatment of gypsum in boiling 1M, 2M, 3M, 4M and 4,5M solutions of magnesium chloride, at atmospheric pressure, in order to obtain α-CaSO 4 -0,5H 2 O was performed. Three mechanism of α-hemihydrate formation were identified in solutions of different concentrations. Gypsum transformation into α-hemihydrate operated in solid phase, through an intermediate product, β-hemihydrate, in solutions of low concentrations (1M and 2M), direct in solutions of high concentrations (3 and 4M) and in solid phase in the solution of the highest concentration (4,5M). Specific surface areas of the obtained products indicated that slow transformation processes (regardless of the mechanism involved) gave products of small surface areas, or high usability
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Page 1. THE HYDROTHERMAL-METAMORPHIC FORMATION OF VEIN MAGNESITE DEPOSITS ASSOCIATED WITH ULTRAMAFIC COMPLEXES B. Vakanjac, B. Petrović, R. Tomanec and VI Starostin Translated from "Gidrotermal ...
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1) Prof.; University of Belgrade, Faculty of Mining and Geology, 7, Djusina str. 11000 Belgrade, Serbia; email: tomanec@rgf.bg.ac.rs 2) Doc. Ing., Ph.D.; VSB – Technical University of Ostrava, Faculty of Mining and Geology, Czech... more
1) Prof.; University of Belgrade, Faculty of Mining and Geology, 7, Djusina str. 11000 Belgrade, Serbia; email: tomanec@rgf.bg.ac.rs 2) Doc. Ing., Ph.D.; VSB – Technical University of Ostrava, Faculty of Mining and Geology, Czech Republic; email: vladimir.cablik@vsb.cz 3) Ing.; Mining Institute Zemun, Serbia 4) University of Belgrade, Faculty of Mining and Geology, 7, Djusina str. 11000 Belgrade, Serbia
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The methods are described of selective separation of thallium mineral lorandite from the Allchar hydrothermal-volcanogenic Sb-As-Tl deposit (FYR Macedonia) characterized by relatively complex mineralization. In addition to antimony and... more
The methods are described of selective separation of thallium mineral lorandite from the Allchar hydrothermal-volcanogenic Sb-As-Tl deposit (FYR Macedonia) characterized by relatively complex mineralization. In addition to antimony and arsenic, the Allchar Mine at the village of Majden works one of the richest thallium mineral lorandite deposits. The aim of the research was to separate lorandite as much and as free grain as possible mainly through physical concentration. Thallium is very important because of a possibility to apply its mineral lorandite (TlAsS2) in obtaining knowledge in fundamental investigations. The reaction between Tl and solar neutrinos, producing Pb, is on the purpose of studing the neutrino flux from the Sun. For this purpose, a thallium-rich mineral is required as the target. Geochemically natural, pure thallium mineral lorandite is used to test solar neutrino under the current, two decades long LOREX Project. The Allchar ore from Crveni Dol contains a compar...
Research Interests: Geology and Geochemistry
Rudolf TOMANEC , Milica STEFANOVIC , Vladimír ČABLÍK 3) _________________________ 1) Prof. Dr.; Faculty of Mining and Geology, University of Belgrade; 7, Djusina str., 11000 Belgrade, Serbia; e-mail: tomanec@rgf.bg.ac.rs, tel.: (+381)... more
Rudolf TOMANEC , Milica STEFANOVIC , Vladimír ČABLÍK 3) _________________________ 1) Prof. Dr.; Faculty of Mining and Geology, University of Belgrade; 7, Djusina str., 11000 Belgrade, Serbia; e-mail: tomanec@rgf.bg.ac.rs, tel.: (+381) (11) 3237 322; 2) Faculty of Mining and Geology, University of Belgrade; 7, Djusina str., 11000 Belgrade, Serbia 3) doc. Ing., Ph.D.; Institute of Clean Technologies for Mining and Utilization of Raw Materials for Energy Use, Faculty of Mining and Geology, VŠB – Technical University of Ostrava; 17.listopadu 15, 708 00, Ostrava-Poruba, Czech Republic; e-mail: vladimir.cablik@vsb.cz, tel.: (+420) 597 324 040
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Tests presented in this work are conducted on samples of the Pb-Zn-Fe-Au poor mineralization from the Grabova Reka deposit, Ist Serbia. The methods are described of selective separation of auriferous minerals and accessory sulphides from... more
Tests presented in this work are conducted on samples of the Pb-Zn-Fe-Au poor mineralization from the Grabova Reka deposit, Ist Serbia. The methods are described of selective separation of auriferous minerals and accessory sulphides from complex quartz veins, small gold deposits, in Blagojev Kamen area (Grabova Reka deposit) characterized by nonunion and relatively poor gold mineralization (Au, Au+Ag, electrum, Au+Fe, Au+Pb, Au+scheelite). Gold prevailing occurs in small grains (5÷10 rarely 100 μm) contained in quartz, pyrite or in galena of pinkish shade from alloying with Bi and Cu. Electrum, a natural alloy of Au and Ag varies in grain size, but generally, electrum is found in large grains (0.5 mm on average) in the form of conglomerate where electrum is cementing cataclastic grains of pyrite (or as inclusions in pyrite and in galena) and other Pb-Zn sulphides. There are many deposits, in the mentioned region, with numerous outcrops of quartz veins with the gold rates from 10 g/t...
Research Interests: Chemistry and Gold mining
The lab tests have been carried out to examine the influence of different factors on selectivity of chalcopyrite flotation from copper sulfides with moderate content of pyrite. The authors use the factorial design of the experiments. It... more
The lab tests have been carried out to examine the influence of different factors on selectivity of chalcopyrite flotation from copper sulfides with moderate content of pyrite. The authors use the factorial design of the experiments. It is studied how grinding fineness and xanthate concentration influence flotation of chalcopyrite and pyrite at different lime-adjusted pH values of pulp. It is found that the highest influence on copper recovery is exerted by the size of the ground ore, pH value and collector consumption. In view of the high activity of pyrite and the intergrowth of chalcopyrite and pyrite with gangue, it is required to grind ore up to 75–80% content of size–74 μm, while pH of the pulp is to be maintained at the level of 11 in all flotation circuits.
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ABSTRACT
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INFLUENCE OF SOME PROCESS PARAMETERS ON THE QUANTITY OF HEMIHYDRATE PRODUCED IN AQUEOUS SALT SOLUTIONS. S Marinkovic, A Kostic-Pulek, R Tomanec Ceramics Today-Tomorrow's Ceramics. Proc. 7 th Int. ...
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Explorations of the ore bodies Prlovi 1, Prlovi 2 and Z of the mined ore deposit Prlovi have included ore microscopy of mineral samples from many boreholes. The orebody Prlovi 2 is prospective for the lead (4%) and zinc (3%)... more
Explorations of the ore bodies Prlovi 1, Prlovi 2 and Z of the mined ore deposit Prlovi have included ore microscopy of mineral samples from many boreholes. The orebody Prlovi 2 is prospective for the lead (4%) and zinc (3%) concentrations of which 1.89% Pb and 1.58% Zn occur in sulphides and 2.17% and 1.44% in oxides. The purpose of the ore microscopy was to recommend, based on mineral composition and texture, how to enrich the complex sulphideoxide mineral. The paper describes the composition of the intergrown minerals and suggests the method of the mineral product recovery. Illustrations in the paper are good representative microphotographs of the identified and characteristic structural features.
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As intensive exploitaton of mineral resources has had many undesirable impacts on environment, both in Europe and Serbia, environmental protection is becoming the priority task and occupation of 21st century. The research represented in... more
As intensive exploitaton of mineral resources has had many undesirable impacts on environment, both in Europe and Serbia, environmental protection is becoming the priority task and occupation of 21st century. The research represented in this paper has been carried out on a technogenic raw material waste, the quantities of which are undoubtedly the biggest ones and keep on increasing.Exploitation, separation, coal processing and utilization are certainly among the biggest environmental pollutants. The procedures of characterization and utilization of fly ash created by lignite combustion at the thermal plant Nikola Tesla in Obrenovac (Serbia) are presented in this paper. The tests on the fly ash are related to determining basic physico-chemical, morphological, magnetic and mechanical features. The knowledge of mineral composition and properties of particular components separated from fly ash enables their adequate commercial and safe utilization. The elements determining its usabilit...
Research Interests: Engineering and Fly Ash
Part of large-scale industrial test results of milling fineness influence on lead, copper and zinc minerals flotation results in the Rudnik flotation plant are shown in this paper. Based on industrial research it has been concluded that... more
Part of large-scale industrial test results of milling fineness influence on lead, copper and zinc minerals flotation results in the Rudnik flotation plant are shown in this paper. Based on industrial research it has been concluded that one-stage milling and two-stage classification of complex Pb-Zn-Cu ore leads to so-called “differential milling”. Namely, galena has much faster comminution than other minerals present in ore due to galena softness. This occurrence leads to galena converting into small particles size fractions which have low flotation rate and, at the same time, copper and zinc minerals stay “unliberated” in coarse particle size fractions (minerals are not free of mutual bonds). In this paper, recorded copper minerals flotation products results are shown, including lead underflow (copper flotation input), copper concentrate and copper underflow, in function of particle size; particle size distribution, minerals and metals distribution in function of particle size were determined; obtained research results confirmed “differential milling” assumption, as well as severe floatability difference between chalcopyrite of a different particle size.
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The characterization of textural properties of minerals is closely related to the process of their respective liberation. Measurements ofmineral liberation, related to grinded ore, can be performed using optical ore microscope, by... more
The characterization of textural properties of minerals is closely related to the process of their respective liberation. Measurements ofmineral liberation, related to grinded ore, can be performed using optical ore microscope, by conventional, classical methods – pointcounting, linear intercepts method or planimetric measurements method (2D). Modern automatic devices and sophisticated measurement techniques (QEMSCAN/MLA) imply recording free surfaces area of mineral grains on polished sections samples in orderto determine mineral degree of liberation. Value of mineral liberation obtained over free surfaces area can be of interest to flotationconcentration, although not for gravity separation or, for example, magnetic separation. The prediction accuracy for behavior of onefeed ore during the concentration process depends on the method of measuring/recording mineral liberation. Considering raw materials with complex textural characteristics it is crucial which method will be applied ...
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This paper presents some investigation results about connection between degree of minerals liberation and flotation, responding to flotation plant “Veliki Krivelj”. There are two main degrees of liberation among the sulphide minerals and... more
This paper presents some investigation results about connection between degree of minerals liberation and flotation, responding to flotation plant “Veliki Krivelj”. There are two main degrees of liberation among the sulphide minerals and gangue, and copper minerals and pyrite. Both of two liberation degrees strongly affect on flotation recovery of copper minerals as well as on copper concentrate grade. This paper deals with figures which give some dependence among the degree of liberation, copper recovery and concentrate grade.
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High Sb and As contents in zink and lead concentrations, have always been obtained by conducting experiments with flotation concentration of complex poly-mineral Pb-Zn-Sb-As-(Ag, Au) ore ground to varied grinding finenesses. Chemical... more
High Sb and As contents in zink and lead concentrations, have always been obtained by conducting experiments with flotation concentration of complex poly-mineral Pb-Zn-Sb-As-(Ag, Au) ore ground to varied grinding finenesses. Chemical analyses were not sufficient to explain this phenomenon. With the help of detailed mineralogical analyses of the run-of-mine ore, and, the obtained concentrates that followed, the problem has been solved. All ore minerals were identified, the degree of liberation of galena and marmatite measured, and the frequency of occurrences of certain types of binary, ternary and higher locked grains determined. The measurements of the liberation degree of galena and marmatite (at the fineness of grinding of 83% -0.074 mm), in the obtained concentrates have shown that the increase in a grinding fineness can only partially result in the increase in recovery and provide better concentration results. In addition, the use of new selective low-cost flotation reagents is...
ABSTRACT
The effect of lead ions on the galena and sphalerite surface properties, ethylxanthate adsorption and kinetics of ethylxanthate adsorption in alkaline medium were studied for the possible use of recycled flotation water. The flotation... more
The effect of lead ions on the galena and sphalerite surface properties, ethylxanthate adsorption and kinetics of ethylxanthate adsorption in alkaline medium were studied for the possible use of recycled flotation water. The flotation tests and the zeta-potential measurements were ...
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ABSTRACT