Mining, Volume 5, Issue 1 (March 2025) – 8 articles

This paper focuses on the solvometallurgical properties of choline chloride-based deep eutectic solvents for copper extraction from chalcopyrite concentrate. The study, conducted with scientific rigor, utilized the response surface methodology to optimize the extraction process and investigate the effects of the temperature and contact time on the copper recovery efficiency. The results showed that the ChCl-EG-Ox solvent at 80 °C and 48 h produced the highest copper recovery rate, exceeding 76%. This underscores the potential of deep eutectic solvents for sustainable metal extraction. Kinetic studies revealed the influence of temperature on dissolution kinetics, with higher temperatures leading to faster reaction rates. The mineralogical analysis demonstrated the changes in the chalcopyrite concentrate after dissolution, while spectroscopy and mass spectrometry highlighted the esterification reactions in the solvent. The study also examined the effects of adding water and heating on the solvent’s behavior, providing insights into the chemical interactions and structural changes. Ultimately, the research demonstrated that ChCl-based deep eutectic solvents present a promising avenue for environmentally friendly and efficient copper extraction processes in the metallurgical industry. Full article

Drilling and blasting is the conventional method used for rock fragmentation in open pit mining. Blast-induced damage can reduce the level of stability of benches and pit slopes. To develop an optimal blast design, an adequate knowledge of the rock properties and in situ fractures is needed. Fractures are generally the paths of least resistance for explosive energy and can affect the intensity of blast-induced damage. Discrete Fracture Networks (DFNs) are 3D representations of joint systems used for estimating the distribution of in situ fractures in a rock mass. The combined finite/discrete element method (FDEM) can be used to simulate the complex rock breakage process during a blast. The objective of this paper is to develop a methodology for assessing the influence of in situ joints on post-blast fracturing and the associated wall damage in 2D bench blast scenarios. First, a simple one-blasthole scenario is analyzed with the FDEM software Irazu 2D and calibrated based on a laboratory-scale blasting experiment available from previous literature. Secondly, more complex scenarios consisting of one-blasthole models at the bench scale were simulated. A bench blast without DFN (base case) and one with DFN were numerically simulated. The model with DFN demonstrated that the growth path and intensity of blast-induced fractures were governed by pre-existing fractures, which led to a smaller wall damage area. The damage intensity for the base case scenario is about 82% higher than for the blast model with DFN included, which highlights the significance of in situ fractures in the resulting blast damage intensity. The methodology for developing the DFN-included blasting simulation provides a more realistic modeling process for blast-induced wall damage assessment. This results in a better characterization of the blast damage zone and can lead to improved slope stability analyses. Full article

The selection of an appropriate mining method, along with the corresponding machinery, is a crucial and highly strategic decision in the field of mining engineering. This decision directly influences the efficiency, safety, and economic viability of a mining operation. An optimal combination of mining techniques and equipment is essential to ensure the effective exploitation of the ore deposit while minimizing costs and maximizing productivity. This paper briefly overviews existing mechanized mining machines for narrow reef mining. The NRE fleet is presented in more detail, together with the results of trial tests conducted using the NRE Drill Rig in narrow reef platinum mines situated in the Great Dyke of Zimbabwe and the Bushveld Igneous Complex in South Africa. The trials were carried out using two distinct mining layouts: the bord and pillar layout and the breast mining layout. The test results clearly demonstrated that the Drill Rig is more effective in breast mining layout compared to the bord and pillar layout in narrow reef mining. The breast mining layout showed superior performance in terms of the number of drilled boreholes and overall efficiency despite the lower availability and utilization of the Drill Rig. Full article

Automation is increasingly gaining attention as the global industry moves toward intelligent, unmanned approaches to perform hazardous tasks. Although the integration of autonomous technologies has revolutionized various industries for decades, the mining sector has only recently started to harness the potential of autonomous technology. Lately, the mining industry has been transforming by implementing automated systems to shape the future of mining and minimize human involvement in the process. Automated systems such as robotics, artificial intelligence (AI), the Industrial Internet of Things (IIOT), and data analytics have contributed immensely towards ensuring improved productivity and safety and promoting sustainable mineral industry. Despite the substantial benefits and promising potential of automation in the mining sector, its adoption faces challenges due to concerns about human–machine interaction. This paper extensively reviews the current trends, attempts, and trials in converting traditional mining machines to automated systems with no or less human involvement. It also delves into the application of AI in mining operations from the exploration phase to the processing stage. To advance the knowledge base in this domain, the study describes the method used to develop the human–machine interface (HMI) that controls and monitors the activity of a six-degrees-of-freedom robotic arm, a roof bolter machine, and the status of the automated machine. The notable findings in this study draw attention to the critical roles of humans in automated mining operations. This study shows that human operators are still relevant and must control, operate, and maintain these innovative technologies in mining operations. Thus, establishing an effective interaction between human operators and machines can promote the acceptability and implementation of autonomous technologies in mineral extraction processes. Full article

The social acceptability (SA) of mining projects is a crucial issue for the sustainable development of territories and local communities. This article aims to identify the issues and examine the factors influencing the SA of exploration, exploitation and processing projects of critical and strategic minerals (CSMs) in Quebec. A systematic review guided by the PRISMA approach was conducted, selecting 57 relevant documents after excluding several others. The results reveal that between 2000 and 2024, the publication of studies on SA in the mining sector has increased significantly, particularly since 2013. Research is mainly concentrated in North America, with a predominance of case studies. Their critical analysis indicates that the SA of mining projects is based on various issues, including the need for greater consideration of the perspectives of local communities, as well as open and inclusive communication between all stakeholders. However, SA is affected by various factors, including demographic, economic, environmental and governance, which can have positive or negative effects depending on the context. Following this analysis, future research should explore the complex interactions between these factors, determining how some may act as mediators or moderators in various contexts through real case studies. Full article

This study presents a gravity survey conducted for mineral exploration in the Gerolekas overthrust area at a bauxite mining site in Central Greece. In the summer of 2018, a gravity survey, covering 28 km², was conducted, including confirmed and unexplored zones. By utilizing gravity data, we investigated the shallow subsurface geology and structural sequences, resulting in a high-resolution 3D density model. This model is generated through constrained gravity inversion by the exploitation of the boreholes available at mining sites, and the geological survey fills the areas with boreholes, which provides the stratigraphy to some depth. The suggested data-processing techniques provide information for the tectonism of the area, which is also important for mineral exploration, as well as mining design. The interface with density contrast between the flysch and the underlying limestone in the high-resolution 3D density model provides useful information on the geological status, but also, the slight density difference in limestone provides an interface where bauxite deposits can be. The inversion, conducted with EMIGMA software, incorporated high-resolution topography data and density constraints to produce a reliable 3D density model. The findings highlight the gravity method’s potential to enhance mineral exploration efficiency, offering a robust tool for further geological and mining considerations. Full article

To enhance the efficiency of mine planning, mining companies wish to understand the structure and extent of ore-bearing rocks as well as possible. Conventional seismic reflection surveys are not well suited for this purpose as they provide an image containing only the location of reflectors, and do not provide physical property information to discriminate between ore and gangue material. Full-waveform inversion (FWI) is a powerful inversion technique, which is able to recover the physical properties of the subsurface at a far greater spatial resolution and accuracy than conventional seismic methods. In this study, we synthetically examined the feasibility of using FWI to image quartz vein-hosted gold deposits. We utilised the Curraghinalt gold deposit in Northern Ireland to parameterise our models, where mineralisation is bound entirely to thin (1–3 m) and steeply dipping (>45°) quartz sulphide veins. Firstly, we demonstrated that a conventional surface seismic reflection survey geometry alongside FWI is infeasible for imaging quartz vein-hosted gold deposits. Secondly, we explored a cross-hole seismic survey geometry consisting of sources and receivers placed down vertical boreholes. This cross-hole survey geometry is capable of generating synthetic datasets such that FWI can recover the position of the veins in space accurate to within 0.5 m relative to their true positions, and recover their physical properties with an accuracy greater than $90\%$, beginning from an entirely homogeneous starting model. We conclude it is essential the source and receiver boreholes be positioned such that both transmitted and reflected arrivals are present in the datasets, otherwise FWI will fail to accurately recover the position and physical properties of the veins. This opens a new avenue for FWI to play a major role in the planning stages and development of gold mines around the world. Full article

The use of pumpable emulsion explosives in the stopes of narrow-reef gold mines is an emerging practice. This is due to recent developments in the delivery and placement mechanisms of emulsion and gassing agents through portable charging units into small-diameter blastholes. With these developments, this paper outlines the performance of pumpable emulsion explosives in a non-trial basis at two underground gold mines in South Africa, where a combined 33 underground drilling and blasting outcomes were observed in two shafts, where three key performance indicators—namely face advance, powder factor, and fragmentation size distribution—were evaluated. The results indicated that the use of emulsion explosives can enhance the probability of achieving the target face advance, whereas the results of the powder factor are mixed. In one shaft, the actual powder factor of the observed blasts mostly exceeded the planned powder factor, whereas in the other shaft, the latter was largely achieved. Lastly, the results of the fragmentation size distribution analyses are inconclusive; that is, it cannot be conclusively pointed out whether the use of pumpable emulsion explosives can achieve a mean particle fragmentation range of 11.5 cm to 13.5 cm at Shafts A and B. Full article