renewed interest in lateritic ores, yet Kazakhstan’s substantial resources remain underused due to the lack of effective extraction technologies. This study provides the first comprehensive mineralogical and processing evaluation of laterite ore from the Kempirsay deposit and demonstrates the applicability of the sulfation roasting-water leaching (SR-WL) method to Kazakh high-iron laterites. Physicochemical analysis showed that Ni and Co are mainly hosted in Fe-bearing phases goethite, hematite, and trevorite with minor incorporation in silicates; the ore contains, (in wt.%):1.08 Ni, 0.104 Co, and 20.2 Fe. Roasting at 500 °C with 30 wt.% H2SO4 generated readily leachable sulfates, and subsequent leaching at 85 °C (180 min, S: L = 1:6) extracted 93.3% Ni, 92.0% Co, and 84% Fe. Selective dissolution was achieved by roasting at 700 °C with 50 wt.% H2SO4, yielding 90.08% Ni and 90.01% Co while limiting Fe dissolution to 6.12%, producing a low-iron pregnant leach solution (PLS) containing, g·L−1: 2.11 Ni, 0.35 Co, 2.12 Fe. Overall, the results show that the SR-WL process is a viable and newly validated pathway for converting low-grade Kazakh laterites into Ni-Co intermediates suitable for modern metallurgical supply chains.

In open-pit mining, bulk material transportation largely determines productivity and energy costs. Air-cushion belt conveyors reduce friction and wear compared to traditional systems, yet their comprehensive evaluation under real mining and geometric conditions remains limited. Intelligent modeling and automated monitoring enable real-time assessment of key parameters and justify modernization aimed at improving energy efficiency and reliability of logistics systems. The objective of this study is to develop and validate a methodology for assessing the production and economic performance of air-cushion belt conveyors in open-pit mining operations using intelligent modeling and an automated monitoring system. The proposed approach takes into account complex mining and geometric conditions and is aimed at improving the energy efficiency, reliability, and sustainability of transport systems. The methodology combines real-time data collection, digital modeling using artificial intelligence algorithms, and industrial testing at an operating mining facility. Key performance parameters, such as energy consumption, stability, fault tolerance, and automation, are assessed. A comparative analysis of technical and economic indicators before and after the implementation of intelligent technologies is conducted. The results confirm the feasibility and benefits of upgrading air-cushion conveyor systems in combination with artificial intelligence-based tools. This methodology can be applied to optimize bulk material transportation in quarries and improve the overall efficiency of production logistics in the mining and construction industries.

When actual intensity of transport traffic considerably exceeds the planned values, it leads to accelerated wear of road surface and formation of rutting. This problem is actual on high- speed main streets of Almaty city. Rutting in asphalt concrete pavement, especially in the areas of expansion joints, causes impacts of motor vehicles' wheels on the ends of joints (metal trims). Such loads lead to rapid failure of all expansion joints that are fixed in the roadway. It is obvious that the increase in traffic volume contributes to the increase in damage, but it is worth noting that uniform loading with a certain frequency leads to the same result, whereas impact loads occurring after the appearance and progression of damage have a much more damaging effect. To date, most efforts to reduce potholes and rutting at joints with expansion joints have focused on reducing rutting, especially in the areas adjacent to expansion joints.

Research analysis reveals factors influencing third-phase crud formation and composition during metal extraction, including solution composition, solid suspensions, organic compounds, colloidal compounds (e.g., silicic acid), and extractant purity. Compositional analysis of copper-containing sulfuric acid solutions (1.25 g/dm3 copper) identifies principal sulfate-forming components. Copper extraction was studied using extractants LIX 984N, ACORGA M5774, and M5640 at different ratios of the organic phase to the aqueous O:A (from 1:2 to 1:10). Suppressive impact of 10 vol.% CR60 additive on third-phase crud formation during copper extraction with LIX 984N, ACORGA M5774, and M5640 is analyzed, with ACORGA M5774 being the most effective. Physicochemical analysis characterizes CR60’s active substance as poly(sodium 4-styrenesulfonate) with steel-suppression properties, and its structural formula is determined. Optimal copper extraction conditions establish ACORGA M5640’s 24% efficiency, followed by ACORGA M5774 at 15%. CR60 reduces crud formation, with 5 cm3 of ACORGA CR60 added to sulfuric acid solution reducing interfacial crud formation by 2–3 times. Optimal extraction parameters include 1:2 O:A ratio, 20 ± 5 °C temperature, 5 cm3 CR60 additive, 5 min process duration, and 1-day settling time. ACORGA M5774 (10 vol.% in kerosene) is recommended as an extractant, with 2–3 stages of countercurrent extraction.

The mining industry is the most important industry in our country, given the abundance of minerals. Most of the most important minerals are found in rocks, often deeply located, which complicates the extraction process. Modern air compressors used in the mining industry must have a high margin of safety when operating in diffi cult conditions: these are uneven terrain, high temperature diff erences, and work underground. This study investigated the technological scheme of the gas pumping process, calculated the compressor, and created a model of the system using MATLAB. The dependence of the compressor outlet pressure on the rotor speed of the motor was identifi ed

Due to the sharp increase in demand and prices for nickel and cobalt, the search for new sources of raw materials has become a pressing issue. This study presents a comprehensive thermodynamic and kinetic analysis of the combined method of oxygen-deficient oxidative roasting and subsequent acid leaching to extract nickel and cobalt from pyrite waste sourced from Kazakhstani enterprises. The thermodynamic analysis showed that, under oxygen deficiency, thermal decomposition of higher sulfides forms non-stoichiometric, soluble lower sulfides of iron, nickel, and cobalt. The kinetic study revealed that the process is complex and multi-stage, and that it proceeds at a high rate in the 610–680 °C range, where kinetic factors control it. Activation energies were calculated for three stages: 105–115 kJ/mol for Stage I (450–479.3 °C), 310–320 kJ/mol for Stage II (661.8 °C), and 390–420 kJ/mol for Stage III (749.7–789 °C). Experimental studies confirmed the effectiveness of roasting at 700 °C for 60 minutes. Subsequent sulfuric acid leaching of the obtained sinders under optimal conditions (sulfuric acid excess coefficient R of 1.5 times the stoichiometric amount, temperature of 100 °C, and a duration of 2 hours) yielded high metal recoveries: 94.5% Fe, 93.4% Ni, and 91% Co. The developed technology, combining thermal activation and leaching, proved effective and is recommended for processing similar raw materials.

In this article, the analysis of safety, reliability and efficiency indicators of compressor units according to operating data was carried out. The disadvantages of a commercial nature are revealed, for example, the degree of compressor loading depending on the location of the CNG station, hindering business development. Then the analysis of technical characteristics is carried out, the task is formulated and the most acceptable way of its organizational and technical solution is found. Kazahstan buys compressors for natural gas compression abroad, so, among other things, we are talking about replacing imported products. Foreign CNG compressors with separate drive and protective seals are fundamentally heavy, and have a number of disadvantages that have been identified through long-term operation. The imperfection of compressors associated with safe operation conditions is the main deterrent to the widespread use of natural gas from CNG stations in the city. In our case, the wide commercial introduction of natural gas is hampered by the large areas required for CNG stations based on a compressor with a separate drive.

This article aims to assess the dynamic loads acting on railway track structures during the operation of open wagons in a degraded technical condition, particularly under increased axle load conditions. The study investigates the interaction characteristics between the open wagon and the superstructure of the railway track, focusing on how wear of components and assemblies in the bogie system influences the magnitude and nature of load transmission. A combined experimental and computational analysis of open wagon dynamics was conducted, considering both loaded and empty operating states, as well as varying levels of technical degradation. The findings allow for the identification of critical parameters that influence operational safety and track degradation. Additionally, the study offers recommendations concerning the permissible range of stability margin coefficients and the operating conditions for worn rolling stock under horizontal and vertical loading scenarios. Copyright

This article presents the results of the development and methodology for the selection of rational compositions of polymer and fiber concrete, providing physical and mechanical characteristics of new structural materials for the engineering industry. The novelty of these studies is the proof of the technical feasibility and economic feasibility of obtaining a new composite material that can be used in mechanical engineering in the manufacture of equipment for the mining and metallurgical complex. At the moment, composite materials such as polymer and fiber concrete are widely used in various industries. Studies have revealed that it is rational to use a filler with intermittent granulometry consisting of three fractions. At the same time, smaller fractions fill voids in larger fractions, which increases the density of polymer concrete and its strength. The influence of the main factors on the characteristics of polymer concretes is investigated: the rotation frequency of the mixer working body, the mixing time of the components and the temperature of the resin ED. The technology of mixing the components in two stages has been developed, which ensures the production of a homogeneous mixture and an isotropic material after curing. The conducted studies have confirmed that the use of these materials НАУКА И ТЕХНИКА КАЗАХСТАНА. ISSN 2788-8770. № 2, 2024 73 for body parts in mechanical engineering is not inferior in technical characteristics to traditional materials such as cast iron and aluminum alloys. The equipment used in mining enterprises and metallurgical plants is subjected to severe operating conditions, such as exposure to aggressive media, high dust content, sudden temperature changes, transportation of abrasive liquids, etc. In this regard, in the production of machine bodies and mechanisms, it is necessary to increase their thickness, which leads to excessive metal consumption, difficulties in maintenance and an increase in cost. Replacing traditional metals with composite materials with improved characteristics seems appropriate.

The scientific task of the nozzle scheme uses for formation of an air cushion by using the energy of a jet of air supplied under pressure, simultaneously to form an air cushion, as well as to create the driving force of a load-bearing web, was formulated and the main idea of the work was defined. The optimal option to significantly increase the productivity and length of special types of conveyors is to use the energy of a jet of air supplied under pressure simultaneously as an air cushion and as the driving force of the loadcarrying body, which makes it possible to sharply reduce the coefficient of resistance to movement of the load-carrying body and improve its operating conditions. Supporting the load-carrying body with an air cushion allows to increase the speed of movement to 8 to 9 m/s and more, increase the reliability and safety of conveyor operation, and protect the environment.