Simulation of deposit parameters in underground development mining

The article is aimed at improving development mining to prepare an ore body for stoping by access ramps to provide comfortable conditions and high technical and economic indices in underground mining. Efficient parameters of underground mining are chosen in the course of simulating data on the mining theory and practice considering ore losses and dilution on the basis of critical analysis of uranium mining enterprises’ activities. The research provides data on geological and engineering zoning of an ore deposit and physical-mechanical properties of ore bearing rocks. The advanced experience is systemized and there is provided system analysis of modern development mining schemes with access ramps (ring, spiral, one-way inclined, central inclined and across the strike). The research recommends schemes of development mining and substantiates their advantages. There are quantitative indices of physical simulation of development variants as to drawn ore quality according to criteria of soil location in ore draw points. The scientific novelty implies developing the criterion of optimality and ranking variants of development mining according to technical-economic and geomechanical indices considering some technological factors as well as the number of stopes operating simultaneously on the level. The study consists in increasing authenticity of development projects through applying complex schemes of access ramps according to the complex criterion of increasing mining depths, equipment application, ventilation and underground mine capacity

Дослідження процесів поширення хвиль Лемба по пластині, що контактує із випадково неоднорідним гетерогенним середовищєм

We present results of research into the influence of characteristics of a heterogeneous medium on the Lamb wave propagation process parameters along a plate in contact with a given medium. A mathematical description of the Lamb wave propagation process in a metallic plate was formed. Analytical expressions are derived for determining the displacement potentials that describe, respectively, the longitudinal and transverse waves in a plate with a thickness of 2d at frequency ω. The possibility is shown of the existence under given conditions of a certain finite number of symmetric and antisymmetric Lamb waves. The mentioned waves are different one from another in phase and group velocities, as well as the distribution of displacements and stresses along the plate's thickness.We have investigated dependence of the Lamb wave attenuation on the characteristics of fluid in contact with the propagation medium. In the case when the Lamb wave propagation medium borders the fluid and the speed of sound in liquid Cl is less than speed C of the wave in a plate, the Lamb wave will attenuate radiating energy into liquid. It was established that the attenuation is due to the density of the studied medium. Viscosity and motion speed of a gas-containing suspension, for example iron ore pulp, have almost no effect on the magnitude of attenuation of the Lamb waves.The significance of the obtained results is emphasized by the fact that they could be used to develop improved methods and tools to control parameters of gas-containing suspensions. The use of Lamb waves makes it possible to avoid measurement errors associated with the presence of microdefects at the surface of propagation and gas bubbles in the examined liquid.From a practical point of view, the results obtained could be used for the calculation of parameters for the sources of ultrasonic waves in the systems of ultrasonic testing. Thus, there is an opportunity to improve efficiency of technological processes in the mining and metallurgical industry, specifically, the enrichment of ore.Представлены результаты исследования влияния характеристик неоднородной гетерогенной среды на параметры процесса распространения волн Лэмба по контактирующей с данной средой пластине. Рассмотрено влияние параметров исследуемой среды на величину затухания волн Лэмба. Установлено, что вязкость жидкости и скорость потока не влияют на процесс распространения волн Лэмба. Полученные результаты могут быть использованы при разработке методов и средств контроля параметров газосодержащих суспензийПредставлені результати дослідження впливу характеристик неоднорідною гетерогенного середовища на параметри процесу поширення хвиль Лемба по пластині, що контактує з цим середовищем. Розглянуто вплив параметрів досліджуваного середовища на величину загасання хвиль Лемба. Встановлено, що в'язкість рідини і швидкість потоку не впливають на процес поширення хвиль Лемба. Отримані результати можуть бути використані при розробці методів і засобів контролю параметрів газовмісних суспензі

Використання високоенергетичного ультразвуку для підвищення якості очищення часток залізорудної сировини у процесі її збагачення

The iron-magnetite raw material extracted in Ukraine is characterized by a complex texture, structure, and a high content of harmful impurities such as silicon dioxide, potassium oxides, sodium, magnesium, and sulfur. At the same time, the requirements for the quality of iron ore concentrates entering the further metallurgical processing are increasing, as the high quality of magnetite concentrates can significantly reduce the cost of metallurgical production.Meanwhile, the quality of concentrates decreases mainly due to the formation of technogenic micron splices in the iron ore pulp. The main reason for the formation of gaps is the presence of ion-electric and molecular fields on the surface of the ore particles. The formation of technogenic gaps reduces the difference in the properties of the surface of the ore and nonmetallic grains; it changes their magnetic susceptibility and, consequently, the efficiency of separation methods.Analysis of the results of studying the influence of the dynamic effects of high-energy ultrasound on the ore pulp showed the promising use of this approach.To improve the efficiency of cleaning the surfaces of minerals, it is proposed to pre-treat the iron ore slurry with the help of high-energy ultrasound. The optimum values of the intensity and the duration of ultrasonic treatment in the purification of mineral particles have been determined. When cleaning mineral particles, the intensity should be 1.2 W/cm2, and the processing time should not exceed 60 seconds. In this case, the yield of the purified product is increased by 0.8 %, and its quality grows by 0.9 %. It has been proven that the efficiency of ultrasonic treatment is associated with the renewal of particles surfaces, which leads to an increase in the contrast of magnetic and flotation properties of minerals.The study has shown that ultrasonic treatment of the iron ore pulp in the Kremenchuk iron ore region of Ukraine allows reducing the content of harmful impurities: potassium oxide – from 0.19 to 0.035–0.04 %; sodium oxide – from 0.14 to 0.027 %.Ухудшение качества концентратов в основном происходит в результате образования микронных техногенных сростков. Предложено использование высокоэнергетического ультразвука в кавитационном режиме для очистки поверхностей минералов. Доказано, что эффективность ультразвуковой обработки связана с обновлением поверхностей частиц, что приводит к увеличению контрастности магнитных и флотационных свойств минералов. Выполнен расчет устройства формирования высокоэнергетического ультразвукаПогіршення якості концентратів в основному відбувається внаслідок утворення мікронних техногенних зростків. Запропоновано використання високоенергетичного ультразвуку в кавітаційному режимі для очищення поверхонь мінералів. Доведено, що ефективність ультразвукової обробки пов'язана з оновленням поверхонь часток, що призводить до збільшення контрастності магнітних і флотаційних властивостей мінералів. Виконано розрахунок пристрою формування високоенергетичного ультразвук

Requirements for the content and training of PhD in the specialty of automation and computer-integrated technologies

Метою статтi є розкриття вимог до змiсту та пiдготовки докторiв фiлософiї зi спецiальностi 151 Автоматизацiя та комп’ютерно-iнтегрованi технологiї, виконання яких сприятиме успiшнiй акредитацiї освiтньо-наукових програм iнших спецiальностей закладiв вищої освiти України. Методи дослiдження. Пiд час проведення дослiдження здiйснено аналiз нормативної бази документiв для пiдготовки докторiв фiлософiї, стандартiв вищої освiти, науково-методичної лiтератури, освiтньо-наукових програм закладiв вищої освiти. Результати дослiдження полягають у висвiтленнi основних аспектiв, на якi слiд звернути увагу задля успiшної акредитацiї освiтньо-наукових програм.The aim of the article is to disclose the requirements for the content and training of PhDs in the specialty 151 Automation and computer-integrated technologies, the implementation of which will contribute to the successful accreditation of educational and scientific programs of other specialties of higher educational institutions in Ukraine. Research Methods. The study involved the analysis of the regulatory framework of documents for the training of doctors of philosophy, standards of higher education, scientific and methodological literature, educational and scientific programs of higher educational institutions. The results of the study consist in highlighting the main aspects that should be taken into account for the successful accreditation of educational and scientific programs

Predictive control of the iron ore beneficiation process based on the hammerstein hybrid model

Non-linear, dynamic, non-stationary properties characterize objects of the iron ore beneficiation line. Therefore, for their approximation, it is advisable to use models of the Hammerstein class. As a result of comparing the three models of Hammerstein: simple, parallel and recursive-parallel, it was shown that the best result for identifying the considered processes of magnetic beneficiation of iron ore by the minimum error criterion was obtained using the Hammerstein recursive-parallel model. Hence, it is recommended for the identification of beneficiation production objects

Sustainable development of mining processes based on mechanochemical leaching of ore

Intensive development of the mining and metallurgical complex results in considerable volumes of waste materials, more than half of which are produced by mining enterprises. Modern mining and processing can provide non-waste production only if mineral extraction and grade recovery from natural and technogenic mineral materials are regarded as a single technological process and the Earth surface preservation becomes a priority in determining parameters of process integration. The research is aimed at improving of the technology of metal leaching in a disintegrator through complex application of metallic ore concentration tailings. A radical step of reducing mining waste hazards is their utilization through introducing technogenic reserves of metallic ore concentration tailings into production, thus creating a new raw material base for the mining industry. Substantiation of the concept of non-waste utilization of off-grade mineral materials depends on the amount of integration of chemical leaching and mechanochemical activation in the disintegrator and is achieved by means of modern information technologies

Investigation of Mechanochemical Leaching of Non-Ferrous Metals

The research deals with metal extraction from off-grade ores and concentration tailings. There are provided results of simulating parameters of reagent leaching of metals in the disintegrator according to the metal recovery ratio. The research substantiates the method of waste-free processing of chemically recovered ores. Recovery of metals into solution is the same both under multiple leaching of tailings or ore in the disintegrator and agitation leaching of tailings or ore previously activated in the disintegrator with leaching solutions. The time of agitation leaching is more by two orders of magnitude than that of the disintegrator processing. Recovery of metals into solution is most affected by the content of sodium chloride in the solution. Then, in decreasing order, go the content of sulfuric acid in the solution, the disintegrator rotor rpm and L:S ratio

Study of rock structure properties during combined stopping and development headings

The purpose of this study is to establish the mechanism of interaction between stresses and strains and their quantitative values at the intersection of stopping and development headings to optimize methods for controlling the behaviour of the rock massif. The research complex includes priority methods with experimental confirmation of the calculated parameters by geophysical studies, including stress calculation by a sensor system and surveying levelling to measure deformations using support frames. The properties of the massif and the role of faults and macro-cracks in the development of a field of a complex structure are systematized. A method for studying the stresses and deformations of rocks at the intersection of stopping and development headings is given. The patterns of the rock massif behaviour at the point of intersection are established. The article provides quantitative values of changes in the physical and mechanical properties and stability of rocks at the point of intersection. Massif was differentiated according to the magnitude of the effective stresses in different phases of the intersection. Stresses for specific conditions were calculated with the determination of the reliability of the mining site. The patterns of change in stresses and strains in time are noted

Increasing efficiency of iron ore magnetic separation by using ultrasonic technologies

The research is aimed at solving the topical problem of enhancing efficiency of iron ore magnetic separation by applying ultrasonic technologies to identify optimal technological parameters of magnetic separation, improving controlled structural parameters of a magnetic separator and pretreating slurry by highenergy ultrasound to clean the ore material surface from fine-dispersed particles of minerals and slime, as well as disintegrate ore aggregates fed to the magnetic separator. The main tasks involve identifying regularities of influence of slurry pretreatment by high-energy ultrasound on properties of iron ore magnetic separation, determining regulations of improving technological and controlled structural parameters of the magnetic separator using ultrasonic methods, developing and substantiating methods to enhance efficiency of iron ore magnetic separation by applying ultrasonic technologies