The study addresses the development of an envi ronmentally sustainable and economically efficient technol ogy for processing low-grade molybdenum ore. Methodol ogy: Particular attention was given to the effect of roasting temperature on the phase composition of intermediate prod ucts and the subsequent recovery of molybdenum. Experi ments were carried out in 2023 using ore from a Kazakh stan molybdenum deposit. Results: The results showed that roasting at 550 °C provided the most favorable conditions, yielding up to 88.28% molybdenum trioxide (MoO3) and ensuring a high extraction rate of molybdenum into solution (97.79%). From the purified solution, calcium molybdate (CaMoO4) was obtained that complied with MDK-2 grade requirements, with molybdenum content of 47.6%, phospho rus 0.0317%, and sulfur 0.253%. These findings demonstrate that even low-quality ores can be efficiently processed to produce a commercially valuable product, while minimizing both material losses and environmental impact.

In connection with recent economic events in the world, the problems of providing countries with energy resources have become particularly relevant. A special role in solving these problems belongs to the mining enterprises of Uzbekistan, which today are characterized by the further development of the openpit mining method, one of which is the Angren coal mine. The main task, its relevance, is to present one of the ways to model the optimal options for the operation of cyclic flow t echnology i n d ifficult con ditions of stripping operations. The methods used. In this work, finite e lement m ethods a nd mathematical modeling based on the computer program “Ansys” were used to model the structures of the Central Processing Plant in order to determine the optimal parameters of the unloading and loading bunkers of the central processing plant of the Angren site. The main hypotheses and conclusions. The work carried out, the main factors 183 ISSN 2224-5278 6.2024 affecting the integrity of the belt were identified: the tensile strength of the main belt when unloading rock by the unloading and loading hopper of the Central Processing Plant at various belt speed parameters. Originality. The purpose of this study is computer simulation of the CPU operation process based on the program “Ansys”. Practical significance. The calculation methods used in this study using the finite element method based on the Ansys program can be used to determine the causes of belt conveyor gusts during its operation in various production conditions, when choosing the optimal technical parameters of structures: the height of the production hopper, the speed of the conveyor belt, its angle of inclination and the material of the belt itself

В данной статье рассматривается проблема оптимизации пусковых режимов технологических машин с тяжелым ротором, актуальная для различных отраслей промышленности, включая горно-металлургический комплекс. Предложено использование пневматического пуско-вспомогательного устройства на базе сильфонных пневмобаллонов с храповым механизмом для облегчения пуска таких машин и снижения пусковых токов. Описана конструкция экспериментального стенда, имитирующего работу шаровой мельницы и приведена методика проведения исследований. Показано, что предварительная работа предложенного пневматического пуско-вспомогательного устройства в пошаговом режиме, без включения основного двигателя, существенно снижает пиковые значения пускового тока. Определено влияние давления в пневмосистеме на эффективность пуска, установлено, что увеличение давления приводит к дальнейшему снижению пускового тока. Определены оптимальные параметры работы предложенного устройства (положение конечного выключателя, давление сжатого воздуха), обеспечивающие минимальные пусковые нагрузки на штатный привод. Сделан вывод о перспективности использования предложенного устройства для повышения надежности, энергоэффективности и снижения эксплуатационных расходов на предприятиях, использующих технологические машины с тяжелым ротором.

This study proposes a novel computational method, employing the integral dynamics of multibody systems to simulate the transverse vibrations of the rotor in a cantilever-type centrifugal pump. This method was applied to the kinematic assembly of the rotor and its supports, with the latter modeled as springs possessing stiffness and damping properties equivalent to those of real bearings supporting the shaft in an actual design. To investigate transverse vibrations within the system, three key observation points were defined—at the locations of the left and right bearings, as well as at the rotor’s center of mass—to allow for a thorough dynamic analysis. Additionally, the influence of motor rotational speed and the impeller’s eccentricity on the transverse vibrations of the supports and the shaft was examined. The results have revealed that transverse vibrations significantly affect the system’s dynamics at lower rotational speeds, leading to the classification of the shaft as flexible. As the rotational speed increases, the system exhibits enhanced dynamic stability. Furthermore, it was found that for impellers with a diameter less than 300 mm, the unbalanced forces are negligible and can be disregarded in pump design. To reduce vibration levels, an elastic damping ring was selected and incorporated into the system. This novel method provides an effective tool for analyzing the transverse vibrations of centrifugal pump rotors and for optimizing vibration mitigation strategies.

Introduction. This study focuses on enhancing the energy efficiency, operational stability, and ecological sustainability of screw compressor systems widely used in industrial and mining enterprises. Despite significant progress in compressor modernization, challenges remain in adapting operating modes to variable loads, harsh climatic conditions, and high production demands. This work introduces an integrated approach combining experimental testing and mathematical modeling to develop optimized operating modes based on frequency and vector control of induction motor drives. Methods. The methodology combines laboratory experiments on an industrial screw compressor with numerical simulations of drive dynamics in d–q coordinates. Comparative tests were carried out under scalar and vector control modes using precision measurement equipment for electrical, mechanical, and thermal parameters. Statistical analysis, including averaging and confidence interval estimation, was applied to ensure the reliability of results. Additional simulations extended the analysis to scenarios difficult to reproduce experimentally, such as variable load cycles and fluctuating ambient conditions. Results. The findings demonstrate that vector control reduces starting currents by more than 50%, shortens acceleration time by 25%, and lowers bearing and winding temperatures by up to 9 °C compared to scalar control. Specific energy consumption decreased by 7–14% depending on the load profile, while overall system efficiency improved from 77.9 to 82.6%. Vibration levels during startup were nearly halved, and long-term stability under fluctuating load conditions was significantly enhanced. Calculations further showed that annual energy savings can reach up to 18 MWh per unit, resulting in notable cost reductions and extended equipment lifespan. Conclusions. The proposed approach demonstrates the effectiveness of integrating vector-controlled frequency drives into screw compressor systems, ensuring higher energy efficiency, reduced mechanical stress, and improved reliability. The results provide practical recommendations for industrial modernization projects, offering both economic and ecological benefits. The methodology is particularly relevant for mining enterprises with variable demand profiles and contributes to advancing sustainable industrial development in line with Industry 4.0 principles. © 2025, North Caucasian Institute of Mining and Metallurgy, State Technological University. All rights reserved.

As high-grade gold-bearing ore reserves rapidly become depleted, there is a growing shift towards processing lower-grade refractory ores. These ores contain gold that is finely dispersed, making it more challenging to extract. Gravity beneficiation is a common initial processing method used for these ores. However, due to the extremely small size of the gold particles, significant amounts of gold are lost during this process. This study explores methods to improve gravity beneficiation of refractory gold-bearing ores from the Vasilkovskoye deposit. Physicochemical and particle size distribution analyses have shown that gold particles in the ore samples are very small, ranging from 0.01 mm to 0.074 mm in size. Most of these particles are either dust-like or flaky and are smaller than 0.074 mm. In order to optimize the recovery of fine particles of heavy native gold and gold-bearing minerals, the design of the centrifugal hydroconcentrator was refined and a closed-cycle multi-stage concentration process was developed, which improved the recovery of gold from the Vasilkovskoye deposit ore to 56.7 %. Comparative concentration experiments for various gold-bearing ores, including tailings and waste from several processing plants, have demonstrated that the newly developed gravity beneficiation technology can improve gold concentration efficiency by a factor of 2.38. This advanced technology enables the almost complete recovery of gold particles up to 0.074 mm in size and improves the recovery of very fine, dust-like, plate-like, and flaky gold particles by approximately 15–20 %. The resulting concentrate grades meet the current requirements of gold plants.

Ozonation of water is the most effective method of purifying water and preventing its contamination with various harmful and dangerous components. This method is used in urban water supply. During the purification process, ozone is able to oxidize pollutants of any origin to insoluble compounds that are safe for human health. Ozone is a safe substance for chemical water purification. Ozone water purification is widely used today due to the need for deep purification of water for its reuse. This study examines the results of a comparative analysis of the use of ozone and chlorine reagents in water purification processes. The comparative analysis is presented in the following aspects: the laws of ozone solubility in water, the effectiveness of inactivation of microorganisms, corrosion activity, environmental impact assessment at the stages of the life cycle and life cycle cost assessment. In general, ozone technology is one of the modern methods aimed at effectively purifying water from harmful compounds. The use of ozone for water purification ensures the destruction of bacteria, viruses and other harmful microorganisms, as well as reducing the content of organic and inorganic pollutants. One of the main advantages of using ozone is its high oxidizing ability, which increases the purity of water and facilitates the removal of various pollutants. The work carried out a life cycle assessment, which helps to determine the environmental characteristics of various cleaning agents, including their production, preparation of reagents and the immediate stages of the cleaning process. Based on life cycle assessments, it was possible to predict the potential impact on ecosystems and the depletion of natural resources for various categories of impact, which made it possible to justify the choice of the best technology when comparing alternative technologies. Of all the options considered, sodium hypochlorite is the most effective chlorine-containing reagent. The results of the study, compared with chlorine-containing reagents, revealed the most effective method of water purification based on ozone.

Relevance. The stability of pit walls is a key factor determining the safety and efficiency of open-pit mining operations. Excessive groundwater inflow and the presence of water-saturated zones often lead to slope instability, landslides, and reduced productivity. Therefore, developing effective methods for dewatering pit wall massifs is of great practical significance for ensuring sustainable mining operations. Objective. The objective of this study was to develop and implement a comprehensive system for draining the pit wall massif using newly designed horizontal and slightly inclined boreholes with camouflet cavities to enhance slope stability. Methods. The research methodology involved advanced groundwater interception in formation zones beyond pit boundaries and interception of surface runoff along pit slopes using horizontal, slightly inclined boreholes with camouflet cavities. Experimental investigations were carried out using a polarization optical setup to analyze stress distribution within the rock mass. Field studies included drilling horizontal boreholes in areas of maximum groundwater accumulation, creating camouflet cavities by controlled blasting, and assessing stress redistribution in the dewatered rock mass. The results demonstrated that camouflet cavities formed beyond the rock mass displacement line act as stress concentrators that effectively unload the near-contour zone and enhance slope stability. The introduction of horizontal, slightly inclined boreholes with camouflet cavities ensures efficient drainage of the contour massif, reduces stress concentrations at the slope base, and stabilizes the overall pit wall structure. The proposed set of measures can be widely applied at mining enterprises under similar geological and hydrogeological conditions, contributing to improved safety and productivity in open-pit mining. © 2025, National Academy of Sciences of the Republic of Kazakhstan. All rights reserved.

В условиях цифровизации и растущей глобальной конкуренции крупные организации Республики Казахстан, такие как «Казатомпром» и «КазМунайГаз», активно внедряют современные подходы к управлению проектами. Использование международных стандартов и моделей таких как Stage-Gate и Project Management System, и интеграция собственных нормативных документов позволяют этим компаниям повышать эффективность реализации проектов, минимизировать риски и обеспечивать устойчивое развитие. В статье сопоставляются две ключевые модели проектного управления c анализом практик управления проектами двух ведущих компаний Казахстана.

В данной работе простым гидротермальным методом синтезированы три типа структур кобальтита цинка ZnCo2O4 на никелевой пене: наностержни, нанонити и пластины. Исследованы морфология и структурные характеристики синтезированных образцов. Выращенные структуры могут быть использованы в качестве основы для бесферментных электрохимических биосенсоров. Методом сканирующей электронной микроскопии (SEM) был проведен детальный анализ серии из шести образцов, синтезированных при различных соотношениях Zn:Co (1:1, 1:10 и 10:1). Результаты исследования элементного состава наноструктур ZnCo₂O₄, синтезированных гидротермальным методом на никелевой пене, показали, что состав полученных материалов коррелирует с составом исходного ростового раствора, подтверждая контролируемость процесса легирования. Отсутствие каких-либо примесей свидетельствует о высокой чистоте синтезированных образцов. Полученные данные подтверждают возможность точного управления стехиометрией кобальтита цинка. Показано, что морфология выращенных образцов зависит от стехиометрии прекурсоров, обеспечивая управляемый рост наноструктурированных материалов. Показано, что гидротермальный метод синтеза наноструктур ZnCo₂O₄ позволяет получать материалы с широким диапазоном стехиометрии от кобальт- до цинксодержащих фаз, что открывает возможности для тонкой настройки эффективных, функциональных свойств ZnCo₂O₄.