Advances in Science and Technology Vol. 172

Abstract: This paper substantiates a technological scheme for further development of the flank section of the Chkalovskyi No 1 openpit at the Pokrovskyi MPE to extract manganese ore classified by the EU as critical raw material. Geological and hydrogeological data of the area were analyzed: orebody thickness (avg. ~1.6 m), manganese content (26-30%), overburden layer depth (up to 76 m) and stripping ratio (~23 m³/t). Three mining schemes were evaluated “northtosouth”, “southtonorth”, and “westtoeast” with detailed assessment of preparatory work volumes, capital mining operations, transportation logistics, and equipment deployment (draglines, wheel bucket complexes). The proposed optimal solution leverages existing machinery freed after completion of the main pit operations, ensuring uninterrupted supply of highgrade manganese concentrate and sustaining enterprise production capacity. The suggested phased approach minimizes capital investment and enhances reclamation efficiency. The recommended mining direction balances technical feasibility, ore quality, stripping costs, and environmental rehabilitation, offering a robust strategy to support green transition needs and critical raw material supply security.

Abstract: The presented work is structurally divided into two parts. The first part, using finite element methods and potential theory, presents the results of theoretical research on the patterns of stress field formation in the roof of wide-span drawn stopes. The second part proposes a methodology for determining the strength reserve in flat drawn stopes roofs depending on the span size and depth of their placement, as well as recommendations and innovative technical solutions for drawn stopes support and improving their operational reliability under challenging mining conditions. During the construction of special-purpose chambers under complex mining and geological conditions, workings of elliptical, semi-circular, or circular cross-sections are commonly used. The optimal shape of the underground excavation cross-section is selected based on the stability and fracturing of the surrounding rock. In the development of ore deposits, it is necessary to assess the stress state of both extraction and special-purpose chambers under conditions of three-dimensional stress, where the dimensions of the chamber along the x, y, and z axes are approximately equal.

Abstract: For the first time, a mathematical model of the technological operation of washing away material that has fallen on the site after a landslide using water jets has been created. It describes the movement of part of the mass that has descended the slope along an inclined channel along a thin layer of highly concentrated hydro mixture formed between it and the bottom of the channel from the liquid supplied by hydromonitors, which acts as a grease with the rheological properties of the Bingham-Schvedov medium. The proposed mathematical model allows calculating the increase in the flow rate and density of the hydro mixture in the second stage of the slurry formation process, taking into account not only the redirection of the water monitor jets, but also the proposed methods for calculating the parameters of the slurry formation process, which can be used to reduce the energy intensity of the transportation process and increase its reliability by preventing dynamic phenomena and emergency stops by determining the acceptable parameters of the mode of destruction of the mound by the jets of the hydromonitor.

Abstract: The article presents a digital model for selecting the optimal transport type for hauling dimension stone blocks in quarry operations. The model integrates fuel consumption, transportation cost, block geometry, and pollutant emissions, providing a combined techno-economic and environmental assessment of transportation scenarios. Developed in Google Colab with Python, it ensures flexibility and is linked to Google Sheets for real-time data input without additional software. Key parameters include transport type, road gradient, traction coefficients, equipment productivity, seasonality, fuel use, and emissions of CO₂, NOₓ, SO₂, and PM.The model was tested on production data from the Southern section of the Mezhyrichchia quarry using a CAT 980H wheel loader and a KrAZ-65055 dump truck. Results show that optimized transportation scenarios can cut fuel consumption by up to 31% and reduce costs per 1 m³ by 26%. At the same time, emissions per 1 m³ of commercial stone blocks can be lowered by up to 30% through appropriate equipment selection and reduced idle trips. The model can serve as a decision-support tool in real-time quarry operations, helping minimize fuel overuse and ecological risks. Adapted for small-scale enterprises, it can also be implemented as a mobile application.

Abstract: In the context of varying ore quality indicators at mining open-pit mines, ongoing grade control is very important and affects the economic performance of the mining enterprise. The article analyses modern methods and ways of current grade control. A method for qualitative indicators assessment in an open pit mine and data processing using modern software is presented. An algorithm for grade control in the process of drilling and mining is analysed and presented. The main data is the geological database, which is updated during operational exploration and planning. Updates are carried out during the blast hole sampling and preparation of the massif for blasting. The dense network of blast holes allows to clarify the contours of high-grade and low-grade ores, which allows to control the order of ore material mining and form cargo flows in the open pit. As shown by the comparison of the parameters of waste rock, high-grade and low-grade ores in the mining block using the resource and operating models, the tonnage and quality of materials can be increased or decreased due to clarification. The article presents the grade control workflow in open pit mining as a generalised algorithm using advanced Micromine software.

Abstract: The article discusses environmentally friendly technologies based on the use of renewable energy sources, in particular wind energy, as one of the most promising areas of sustainable development. The authors review the state and dynamics of the development of the renewable energy sector in Ukraine in the pre-war period, as well as analyse its transformation and current challenges under martial law. Particular attention is paid to the key factors that determine the urgent need for the development of renewable energy: energy security, reducing dependence on imported energy resources, environmental requirements and the need to restore disturbed areas. The paper emphasises the advantages of decentralised energy in times of war, including increased resilience of the power system, flexibility in load distribution and reduction of the risk of large-scale outages. The article also highlights the environmental and economic benefits of wind energy, and proves the efficiency of using wind turbines with a vertical axis of rotation, which are characterised by less sensitivity to wind direction, ease of maintenance and adaptability to the difficult conditions of mining regions. Thus, the article highlights the importance of integrating renewable energy into Ukraine's post-war recovery strategy.

Abstract: This study presents a novel approach to optimizing energy consumption in rock destruction by integrating advanced design parameters of cutting elements. A hybrid experimental-computational model was developed to evaluate the specific energy of destruction () across granite, limestone, and sandstone. Key findings include energy savings of 15% in granite, 12.5% in limestone, and 13.7% in sandstone, achieved by optimizing the angle of attack – 30º, edge curvature – 0.5 mm, and applying wear-resistant DLC coatings 2500 HV. Laboratory tests, field experiments, and finite element simulations validated the model's accuracy within ±6%. The study identifies critical parameter interactions, such as angle of attack and coating hardness, reducing shear stresses and wear losses. These advancements lower operational costs by approximately $50,000 annually per excavator and extend tool life. Limitations include the limited range of rock types tested and slight simulation overestimations in abrasive sandstone. Future research should explore adaptive cutting element designs with real-time parameter adjustments using sensor-based systems and machine learning. The findings offer practical recommendations for implementing optimized tools in mining and construction, enhancing efficiency and cost-effectiveness. This work bridges theoretical insights and industrial applications, providing a scalable framework for energy-efficient rock destruction.

Abstract: This research evaluates analytical, semi-empirical, and numerical models for predicting contact stresses in the interaction between rock-destroying elements and rock formations, a critical factor influencing wear, cutting efficiency, and energy consumption in drilling operations. The Hertzian analytical model, semi-empirical model with experimental calibration, and a Finite Element Method model incorporating plastic deformation via the Drucker-Prager criterion are compared for accuracy and applicability. Mock experimental data, based on rock mechanics literature, validates the models, revealing average prediction errors of 28%, 12%, and 4% for the Hertzian, semi-empirical, and Finite Element Method models, respectively. The Hertzian model is computationally efficient but inaccurate in nonlinear conditions, the semi-empirical model balances accuracy and practicality in calibrated scenarios, and the Finite Element Method model excels in complex formations despite high computational demands. Graphical comparisons within the contact radius highlight the Finite Element Method model’s ability to capture plastic effects, making it ideal for optimizing rock-destroying elements design in challenging geological environments. The findings underscore the importance of selecting models based on operational requirements, with the Finite Element Method model recommended for high-precision applications in deep or unconventional drilling.

Abstract: This study presents the development of an advanced 215.9 mm drill bit with an optimized material distribution to enhance wear resistance, durability, and operational efficiency in highly abrasive formations. A comprehensive scanning electron microscopy (SEM) analysis of the powders used in the drill bit's construction was conducted using the TESCAN Mira 3 LMU system. The analysis included tungsten carbide–cobalt (WC–Co) and diamond-containing composite powders. The results revealed that WC–Co powders exhibit high density and uniform particle distribution, making them suitable for load-bearing components, while diamond-containing powders ensure superior cutting performance and wear resistance. Based on these findings, a rational material allocation was implemented: WC–Co-based materials were used for structural elements, and diamond-containing powders were applied in cutting and undercutting inserts. Process was optimized to prevent thermal degradation of the polycrystalline diamond compact (PDC) inserts. The developed drill bit was designed for rotary drilling with an axial load range of 20–80 kN, rotation speeds of 80–250 rpm, and a drilling fluid flow rate of up to 40 L/s. The proposed design is particularly suited for the geological and technical conditions of Kazakhstan’s oil and gas fields, contributing to reduced drilling costs and increased efficiency.