Mechanochemical Activation Ofthe Processing of Gold-Bearing Sulfide Raw Materials

Purpose. The research purpose is to study the physical-chemical properties of ash and slag waste generated during the coal combustion at the Ekibastuz field in Kazakhstan, to determine the possibility of using waste as a secondary resource to reduce the negative human impact on the environment. Methods. The research uses the methods of X-ray phase and differential thermal analysis, as well as chemical analysis. The X-ray phase analysis makes it possible to determine the phase composition and structure of ash and slag wastes, while differential thermal analysis is used to study their behavior with temperature changes. A chemical analysis is performed to determine the composition of ash and slag. Findings. The chemical and granulometric composition of ash and slag waste from the Ekibastuz field coal combustion has been determined. Analysis of the ash chemical composition showed that its main components are silicon and aluminum oxides, as well as a significant amount of iron oxide. The results obtained confirm the possibility of using ash and slag waste as a secondary raw material to reduce the negative impact on the environment. Originality. It has been revealed that the thermal conductivity, ultimate strength and water-absorption of ceramic brick samples depend on the amount of ash added and the firing temperature. The possibility of obtaining building materials with minimum cement content has also been substantiated, which is a new and promising approach, given the high cost of cement as the main building material. Practical implications. The practical value of the research is in solving environmental problems associated with the use of ash and slag waste. Using these wastes as a secondary raw material, it is possible to reduce the anthropogenic burden on the environment, as well as the volume of ash dumps. In addition, vacant land previously occupied by ash and slag mixtures can be used for economic purposes.

Section: Figure 1 Ash and Slag Waste Generation In The Regions Of The...mentioning

confidence: 99%

Studying the properties of ash and slag waste for use in the manufacture of construction products

Nurpeisova,

Estemesov,

Gabbasov

et al. 2023

“…Issues of increasing the geological exploration work efficiency are solved through special research in this area [3]. In a number of gold-bearing provinces of the world, there are known ore and placer deposits, where the predominant part of the native gold grains belongs to fine or submicroscopic grain-size classes [4]. Deposits of this type are found in the United States, Canada and other countries.…”

Section: Introductionmentioning

confidence: 99%

Polygenic gold mineralization in quartz-pebble formations on the Takyr-Kaljir site of the Southern Altai, East Kazakhstan Region

Begalinov,

Peregudov,

Tretyakov

et al. 2023

Purpose. The research purpose is to study the forms of gold occurrence in the Takyr graben alluvial-proluvial deposits in order to develop a low-waste resource-saving processing technology. Methods. At the first stage, in the course of field studies, the geological structure of the site is specified, samples are taken for mineralogical-technological analysis, which includes the following procedures: studying granulometric and mineral composition of detrital material; fractional gravitational beneficiation of the source material; fractional beneficiation of material pre-processed in the autogenous mill (AG mill); studying free (native) and bound gold in beneficiation products, their quantitative assessment. The samples are processed under the three-stage scheme using an autogenous mill for sample preparation. Findings. For the first time, the geological structure of the site has been specified with the identification of the deposits in the Turangi and Tuzkabak suites within its boundaries, as well as granulometric and petrographic composition of gold-bearing deposits, and the specifics of gold bearing. The detrital material, represented by quartz with a sharply subordinate amount of quartzite, quartz diorites and jasperoids, is practically identical in all fractions. Originality. For the first time, various types of gold mineralization have been identified in placer sands: clastogenic, newly-formed hypergene, newly-formed hydrothermal and residual. Fractional beneficiation makes it possible to estimate the gold content in each fraction and gravitational beneficiation products, as well as the ratio of free and bound native gold in different fractions. The largest amount of free native gold has been revealed in fractions of -0.25 + 0.1 mm (60%) and -0.074 + 0.044 mm (~40%). Gold is high-grade (96.5%) with an admixture of silver and iron. Together with gold, ilmenite, zircon, scheelite, native bismuth, as well as barite, galena, sphalerite, and dolomite have been identified. Practical implications. The research results make it possible to reassess the prospects of similar objects, to adjust the scheme and methodology for processing stream-sediment samples, to solve the issues of productive sand processing technology, as well as to improve the efficiency of geological exploration and eliminate the “underestimation” of gold deposits. The results obtained can be recommended for implementation by both domestic and foreign organizations specializing in the exploration and mining of gold deposits.

“…They are based on the transformation of minerals in their place of occurrence through thermal, mass transfer, chemical and hydrodynamic processes into a liquid or gaseous state suitable for transportation and further processing. Geotechnological methods of mining are implemented, as a rule, through wells drilled from the surface to the deposit [4], [5].…”

Section: Introductionmentioning

confidence: 99%

Investigation of the solid oxidizer effect on the metal geotechnology efficiency

Yussupov,

Aben,

Akhmetkanov

et al. 2023

Purpose. The research is aimed at increasing the useful component content in a pregnant solution during in-situ leaching (ISL) using a solid oxidizer and increasing the ferric iron concentration in the leaching solution based on laboratory research. Methods. Laboratory research is performed on a specially developed model electrolyzer for obtaining comparative data on divalent iron oxidation to trivalent iron and the change in the useful component content in a pregnant solution. Firstly, tests are conducted with a basic leaching solution, then on the oxidation of the leaching solution with a solid oxidizer in the form of a lead dioxide plate. Tests are conducted by changing sulphuric acid concentration within 5-50 g/l, amount of divalent iron ions in the solution from 0.5 up to 4.0 g, lead dioxide plate surface area from 19 to 76 cm2. The leaching time is up to 10 hours. Findings. The results of laboratory research on determining the oxidation degree of divalent iron ions and change in the oxidation-reduction potential (ORP) depending on the sulphuric acid concentration and on the initial concentration of divalent iron ions in the initial solution are presented. With a change in the sulphuric acid concentration from 5 to 50 g/l, the oxidation value of divalent iron ions increases from 26.5 to 96.5%, and with an increase in the initial solution concentration of divalent iron, the oxidation degree of divalent iron naturally decreases from 95.2 to 58.8%. In the initial leaching solution, the divalent solution concentration is 312 mg/l, and that of the trivalent solution is 288 mg/l. After oxidation with a solid oxidizer, the divalent and trivalent iron concentrations are 56 and 392 mg/l, respectively. In the course of further laboratory research using core materials from a uranium deposit, it has been revealed that when leaching with a basic solution, the uranium content in the pregnant solution is 19.36 mg/l, and when leaching with a solution after oxidation with a solid oxidizer, it is 27.9 mg/l, which is by 8.54 mg/l more. Originality. New dependences have been determined of the oxidation degree of divalent iron ions to trivalent one on the sulphuric acid concentration and on the initial concentration of divalent iron ions, as well as the useful component content in the pregnant solution on the leaching time when using a solid oxidizer. Practical implications. Using of a solid oxidizer, it is possible to increase the trivalent iron concentration in the leaching solution and the useful component content in the pregnant solution compared with the basic technology, thereby reducing the time of mining uranium reserves. Proposed technology is environmentally friendly, with low capital costs.