Kompleksnoe Ispolzovanie Mineralnogo Syra = Complex use of mineral resources

Assessment of the physical and mechanical characteristics of sand for the production of foam concrete using the two-stage foam injection method

R.E. Lukpanov — 2024-02-05

The article presents the results of experimental studies of the properties of quarry sand to assess their suitability for use in the production of foam concrete. The sites of quarry sand extraction in the territory of the Akmola region are analyzed and their physical and mechanical characteristics are characterized. Evaluation of the physical and mechanical characteristics of sand was made for four types of sand. The main evaluation parameters were: particle size distribution, homogeneity, shrinkage, density and moisture content of sands. The results of the study showed that the physical characteristics of sands vary depending on their type, which indicates the differences in the natural composition and properties of these materials. Evaluation of the homogeneity of the different types of sands confirms the significant differences between the types. The highest homogeneity (x_max=77.45; x_max-1=14.98; Cc=73.5%) was observed in type 1 sand, while type 4 sand shows the minimum degree of homogeneity (x_max=47.30; x_max-1=42.28; Cc=8.7%). According to the test results, the maximum values of both densities in type 2 are: ρ_d=1.519 g/cm², ρ_w=1.951 g/cm², and the minimum values of both densities in type 4 are: ρ_d=1.438 g/cm², ρ_w=1.894 g/cm². The maximum natural moisture content in Type 1 samples is vn=9.5%, while the minimum values are 7.6% and 7.2% (Type 2 and 4). The obtained private density values have a high degree of convergence because the coefficients of variation have very low values: for Type 1 sands are 0.1-0.3%; for Type 2 sands are 0.7-0.8%; for Type 3 sands are 0.5-0.7%; for Type 4 sands are 0.4-0.6% (variation of private density values of dry and wet sands, respectively). Analysis of the results of tests on the shrinkage of samples showed that the maximum shrinkage is observed for sands of type 1 equal to 15.63%, while the minimum shrinkage is characteristic of samples of type 3 and 4 (11.25% and 11.88%). Taking into account the suitability of sand for the production of foam concrete, the most preferable is Type 1 sand mined in the Eltok building sand deposit.

Overview of biodegradable polymers: synthesis, modification and application

M. Samy — 2024-02-13

Biodegradable polymeric represents a growing field. Owing to their wide-ranging properties, both synthetic and natural polymeric materials perform a vital and ubiquitous role in everyday life. Amended natural polymeric materials such as starch, cellulose, lignin, chitosan, cottonseed shell (CTS), and cotton gin trash (CGT) have enhanced properties, while synthetic Biodegradable polymeric materials such as poly (vinyl alcohol) (PVA), biodegradable plastics, biodegradable foams. Bioplastics are a kind of polymers able to be degraded by different microorganisms to small molecules (e.g., H₂O, CO₂, and CH₄). Bioplastics are observed to solve waste materials and biodegradability is just a new material to be exploited at the end of its life in specific terms. They should be used for applications that require cheap methods to dispose of items after it has fulfilled their job (e.g., for food packaging, agriculture, or medical products).

Incorporation of neodymium, holmium, erbium, and samarium (oxides) in zinc-borotellurite glass: Physical and optical comparative analysis

Y. Azlina — 2024-02-22

Investigating the effect of different types of rare-earth oxides on zinc borotellurite glass is important to determine the potential application in optical devices. The addition of rare-earth oxides in zinc borotellurite glass is well-known to enhance the optical properties due to the effects of 4f-4f transitions. In this work, we aim to compare the effect of different rare-earth oxides on zinc borotellurite glass denoted as ZBTNd, ZBTHo, ZBTEr and ZBTSm. The glass samples were successfully fabricated via the melt-quenched technique. The physical investigation of the glasses has been done by measuring the density and molar volume. It was found that ZBTNd glass has the lowest density than the other glasses due to the small atomic radius in neodymium oxide. High-density value for ZBTHo glass shows potential to be used as radiation shielding properties. The high value of molar volume for ZBTNd glass is advantageous for fiber optics as ZBTNd glass has good performance in elasticity. It was found that ZBTEr has a lower refractive index than the other glasses due to low dispersion characteristics. However, ZBTEr glass has good performance to be used in optical communication applications. It was found that the optical absorption shifts to a longer wavelength beginning from ZBTEr > ZBTHo > ZBTNd > ZBTSm. The optical band gap energy for ZBTEr glass is higher than the other glasses due to the Coulomb repulsion energy for erbium which is greater than neodymium and samarium and slightly higher than holmium. The pattern of electronic polarizability for all glasses was found as follows ZBTSm>ZBTNd>ZBTEr>ZBTHo. The optical basicity for ZBTEr was found highest which indicates a higher acidity, meanwhile, the ZBTNd glass has the lowest value which corresponds to a higher basicity.

Nature of ree accumulation in clayey interlayers and coals in Karaganda coal basin

A.N. Kopobayeva — 2024-02-23

It is the first completed complex mineralogical and geological research of REE (Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) in the coals of Karaganda coal basin in Central Kazakhstan. This paper presents the results of the research of REE (from lanthanum to lutetium and Y) distribution in 85 samples of coal and clayey interlayers of stratum k7 of Karaganda coal basin in the faces of Saranskaya, T.Kuzembayev, Aktasskaya mines. The ultimate composition of clayey interlayer and coal samples was analyzed by the methods of inductively coupled plasma optical emission spectroscopy and inductively coupled plasma mass spectrometry (ICP-OES and ICP-MS). Research of the lateral and vertical discontinuity of the total REE concentration has indicated the presence of mixed types of REE distribution in coals, which supposes various forms of REE migration and different mobility of heavy and light lanthanides within the hypergenesis zone. The established lanthanum-ytterbium (La/Yb) ratio in the coal, which is normalized to UCC and equals La/Yb<1, relates to the coals with Н type of REE distribution, and the one that equals La/Yb>1 and normalized to chondrite belongs to the coals with L type of REE distribution, which allows making conclusions on the presence of independent sources and different mechanisms of REE accumulation in the sediments of Karaganda coal basin. It is also established that the La/Yb ratio grows from coals to clayey interlayers, which indicates a predominantly clastogenic mechanism of REE input to the coals. The prevailing mineral form of the REE in the coal and clayey interlayer samples from the Karaganda coal basin is light lanthanide phosphates. Sparry crystals with CeLaNdPO composition were found in the coal and clayey interlayer samples. It was established that xenotime is the main deportment for Y in many coals.

Review of the current state of knowledge in forecasting and searching for gold deposits in the North-Western Balkhash region

G.K. Umirova — 2024-02-28

The article provides an assessment of the degree of knowledge of the North-Western Balkhash region based on a priori information from the previously conducted complex of geological and geophysical studies. Today, much is known about the geological, tectonic structure of the North-Eastern Balkhash region, the metallogeny of the region, the main structural elements have been identified; there are characteristics of intrusive formations, the age of the main rock complexes has been determined, several mineralization points, ore occurrences and deposits have been discovered. Based on the results of the earlier work, the Dolinnoye, Pustynnoye, and Karyernoye deposits were discovered. They are characterized by promising gold reserves. The determining role when carrying out prospecting geophysical work is played by the degree of exploration of deposits, which makes it possible to formulate an optimal technology for detecting mineralization points and ore deposits and to reduce the risks of erroneous selection of production facilities to the minimum. The article analyzes the level and provides cartograms of the exploration of the North-Western Balkhash region territory by geological surveying, mining operations, sampling and geophysical methods. The geological and geophysical history of research in the territory of the Dolinnoye, Pustynnoye, and Karyernoye deposits was considered. Conclusions were drawn about the level of exploration of the research area and the need for further geophysical work in this territory, due to the high productivity of the area for copper mineralization.

Natural mineral raw materials as granular filtering materials in industrial and waste water treatment

S.K. Myrzalieva — 2024-02-29

Analysis of currently existing methods of natural and waste water treatment from heavy metals has shown that one of the most promising is the sorption method using natural inorganic materials as sorbents: zeolite, diatomite, and vermiculite. The relevance of the topic is dictated by the need to develop an original technology of wastewater treatment and water treatment, which allows constant monitoring of the level of pollution of natural waters by industrial wastewater from metallurgical enterprises. The proposed methods of sorbent modification create a basis for studying the structure, porosity, and sorption capabilities of the mentioned natural materials. All three minerals: zeolite, diatomite, and vermiculite belong to highly porous, structured materials, promising for use as stable sorption systems in water treatment and water purification. The influence of physical and chemical characteristics of natural sorbents and the application of new promising environmentally safe materials and reagents for water treatment are considered. The sorption of copper ions on natural zeolite material before and after its modification by hydrothermal method was investigated. The activity of sorbents was estimated by the value of sorption capacity, i.e. the amount of heavy metal ions absorbed by a unit mass of sorbent based on zeolite and its modified form.

Features of obtaining composite material from hydrophobic clay with antimicrobic properties

D.M-K. Ibraimova — 2024-03-05

A method for obtaining a nanocomposite from hydrophobic clays with bactericidal properties is considered, which plays the role of a drug matrix intercalated agar-agar. Such nanocomposite materials are increasingly used in medicine as matrices for medicines and vitamins using their adsorption properties and long-term exposure. It was established using TEM analysis that halloysite particles from Beloye Glinische deposit are nanoscale and have a cylindrical shape with a length from 200 nm to 1000 nm and a diameter of nanoparticles from 50 nm to 80 nm. The first stage of the bionanocomposites manufacturing process was the treatment of halloysite nanoparticles with silver ions to impart antimicrobial properties, and hydrophobization with a cationic surfactant was carried out at the next stage. It was established by the X-ray diffraction method that the interlayer space of HNT has been expanded from 9.998 Å to 17.5 Å on the result of the cationic adsorption on the HNT. FTIR spectroscopy also proved the adsorption of surfactant molecules on halloysite by the presence of an appropriate absorption band. The adsorption of silver on a nanotube made of halloysite was revealed by the method of energy-dispersive X-ray spectroscopy. Antimicrobial properties of silver-treated and organophilic halloysite have been established and proved by in vitro analyses in microbiological laboratories about Escherichia coli. Hydrophobic samples of these organophilic clays had edge angles higher than 90° and this proves that all samples are hydrophobic. The resulting organophilic clays were intercalated into an agar-agar matrix and were thrown into a solution of calcium chloride, which gave them stability in a liquid medium. It has been practically established that the most optimal bionanocomposite microsphere is a 50% ratio of organohalloysite and agar-agar.

The influence of the hydrogenation process on the microstructure and properties of metallic materials

M. Rutkowska-Gorczyca — 2024-03-05

Hydrogen, which belongs to the group of the smallest elements, can freely penetrate the structure of metallic materials and cause enormous damage. This phenomenon may occur due to various conditions and may have different effects on the properties of materials. Understanding these mechanisms is important in the era of changing to alternative energy sources. This situation may occur in combustion engines powered by hydrogen-enriched fuel. The work analyzed the impact of various hydrogenation processes on the properties of aesthetic steel, which is allergic to the formation of carbides at the grain boundaries, such a microstructure is intended to simulate the least favorable working conditions. The work was aimed at evaluating the effects of different hydrogenation methods on changes in the properties of the AISI 310s steel membrane. In the work, electrolytic hydrogenation and heat treatment procedures in a hydrogen atmosphere were used. Investigations of changes in material properties included microhardness and in-situ strength tests in a scanning electron microscope chamber. Research has shown that both processes increase the hardness of materials and change the characteristics of stretching curves.

On the influence of iron and silicon content on the phase composition of the Al-Fe-Si system

V. Andreyachshenko — 2024-03-12

Increasing interest in intermetallic phases of the Al-Fe-Si system is associated with their high specific strength, corrosion and wear resistance, as well as the low cost of their production. To exhibit the most successful combination of properties, it is necessary to impart a specific compact morphology to the precipitated intermetallic phases. It is important to create an alloy with a composition capable of accepting plastic deformation. The purpose of the work is to develop the composition of an Al-Fe-Si system alloy capable of withstanding plastic deformation and determining the corresponding deformation interval. Based on computer modeling, an alloy composition capable of accepting plastic deformation was developed and the corresponding deformation interval was determined. The simulation was carried out in the ThermoCalc software package, TCAL8 database. It has been revealed that alloys with a high content of both silicon and iron are not characterized by the formation of a single-phase region, however, with a certain combination of alloy components, it is possible to achieve a quasi-single-phase structure, when the content of one phase is observed to be more than 90%. The solidus temperatures for different alloy compositions and the boundary conditions for the existence of phases have been determined. The α phase is present in the system from a temperature of 770°C up to a temperature of 446°C. In composition, it is found in the range from 5 to 35% iron with an amount of silicon of 10% and from 0 to 15% silicon with an iron content of 30%. The maximum amount of α phase was obtained for the Al60-65 alloy; Fe30-32; and Si5-10%, deformation temperature range is 600-450°C. Deformation in this region will ensure processing in a quasi-single-phase region without melting.

Sequential Transportation of Different Oil Batches through the Industrial Pipeline

G.I. Ramazanova — 2024-03-13

In sequential pumping, several liquids with different physical and chemical properties are pumped through one pipeline. The advantages of this method include: using one pipeline to transport different liquids; more complete pipeline loading; and reduced cost of pumping. The paper considers the sequential pumping of two batches of oil blends with different physicochemical properties through an industrial oil pipeline. This is because a batch of high-paraffin oil blend is simultaneously pumped to an oil refinery, and a batch of high-viscosity oil blend is transported further along a pipeline. The difference between the thermal-physical and rheological properties of oil batches imposes a condition on the thermal mode of operation of an industrial pipeline. A mathematical model and algorithm have been created for calculating the sequential transportation of high-paraffin and high-viscosity oil blends. Thermohydraulic calculations of the model show the distribution of hydraulic head, pressure, and temperature of the batches under the operating conditions of pumping units and heating furnaces. The verification and validation of the theoretical analysis was carried out with experimental data measured by the SCADA along the industrial pipeline length. By the thermal mode of sequential pumping, optimal heating temperatures of oil blends were found at the industrial pipeline stations.

Mechanism and technological results of sulfidation roasting of oxidized lead compounds

T.A. Chepushtanova — 2024-04-16

The paper presents the results of a critical analysis of existing technologies for processing lead-zinc ores and industrial products; the relevance of the research lies in the development of methods aimed at additional extraction of zinc and lead in conditions of a rapid decrease in the content of lead and zinc in ores. The paper presents research on the thermodynamic justification of sulfiding roasting, the results of the development of technology for intensifying the process of processing poor, difficult-to-process complex lead-zinc ores and middlings through preliminary thermal activation by sulfiding roasting in a fluidized bed furnace. The mechanism of sulfidation of oxylated lead compounds has been established according to the scheme: PbO → PbO·PbSO4 → PbSO4 → PbS. The results of the physicochemical study of roasting products, as well as the results of magnetic enrichment of cinders, are presented. The results of magnetic separation of cinders after heat treatment of industrial products show that it is possible to separate up to 70% of iron in the form of pyrrhotite into a magnetic product, while the pyrrhotite content in the magnetic product is up to 98.2%. The paper presents a new technological scheme for processing lead-zinc industrial products from enrichment to obtain pyrrhotites with predicted properties.