Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Article Types

Countries / Regions

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Search Results (1,917)

Search Parameters:
Keywords = mining site

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
27 pages, 19149 KB  
Article
Efficient Autonomy: Autonomous Driving of Retrofitted Electric Vehicles via Enhanced Transformer Modeling
by Kai Wang, Xi Zheng, Zi-Jie Peng, Cong-Chun Zhang, Jun-Jie Tang and Kuan-Min Mao
Energies 2025, 18(19), 5247; https://doi.org/10.3390/en18195247 - 2 Oct 2025
Abstract
In low-risk and open environments, such as farms and mining sites, efficient cargo transportation is essential. Despite the suitability of autonomous driving for these environments, its high deployment and maintenance costs limit large-scale adoption. To address this issue, a modular unmanned ground vehicle [...] Read more.
In low-risk and open environments, such as farms and mining sites, efficient cargo transportation is essential. Despite the suitability of autonomous driving for these environments, its high deployment and maintenance costs limit large-scale adoption. To address this issue, a modular unmanned ground vehicle (UGV) system is proposed, which is adapted from existing platforms and supports both autonomous and manual control modes. The autonomous mode uses environmental perception and trajectory planning algorithms for efficient transport in structured scenarios, while the manual mode allows human oversight and flexible task management. To mitigate the control latency and execution delays caused by platform modifications, an enhanced transformer-based general dynamics model is introduced. Specifically, the model is trained on a custom-built dataset and optimized within a bicycle kinematic framework to improve control accuracy and system stability. In road tests allowing a positional error of up to 0.5 m, the transformer-based trajectory estimation method achieved 94.8% accuracy, significantly outperforming non-transformer baselines (54.6%). Notably, the test vehicle successfully passed all functional validations in autonomous driving trials, demonstrating the system’s reliability and robustness. The above results demonstrate the system’s stability and cost-effectiveness, providing a potential solution for scalable deployment of autonomous transport in low-risk environments. Full article
(This article belongs to the Section E: Electric Vehicles)
Show Figures

Figure 1

21 pages, 6332 KB  
Article
Numerical Simulation and Empirical Validation of Casing Stability in Coalbed Methane Wells Under Mining-Induced Stress: A Case Study of Xiaobaodang Coal Mine in Yulin-Shenmu Mining Area
by Zeke Gao, Wenping Li, Dongding Li, Yangmin Ye and Yuchu Liu
Appl. Sci. 2025, 15(19), 10674; https://doi.org/10.3390/app151910674 - 2 Oct 2025
Abstract
This study addresses the issue of coordinated development of coal, oil, and gas resources in the Yulin-Shenmu Coalfield. Taking the 132,201 working face of the Xiaobaodang No. 1 Coal Mine as a case study, the study combines FLAC3D numerical simulation with on-site [...] Read more.
This study addresses the issue of coordinated development of coal, oil, and gas resources in the Yulin-Shenmu Coalfield. Taking the 132,201 working face of the Xiaobaodang No. 1 Coal Mine as a case study, the study combines FLAC3D numerical simulation with on-site monitoring to analyze the impact of mining activities on the stability of gas well casings. Simulation results indicate that mining activities cause stress redistribution in the surrounding rock, with a maximum shear stress of 5.8 MPa, which is far below the shear strength of the casing. The maximum horizontal displacement of the wellbore is only 23 mm, with uniform overall deformation and no shear failure. On-site monitoring showed that the airtightness was intact, and the wellbore diameter test did not detect any destructive damage such as deformation or cracks. Concurrently, fiber optic strain monitoring of the inner and outer casings aligns with simulation results, confirming no significant instability caused by mining activities. The conclusion is that mining activities have a negligible impact on the stability of the gas well casing-concrete composite structure. The dual casing-cement ring structure effectively coordinates deformation to ensure safety. This finding provides a reliable technical basis for the coordinated exploitation of coal, oil and gas resources at the Xiaobaodang No. 1 Coal Mine and similar mines. Full article
Show Figures

Figure 1

21 pages, 5676 KB  
Article
Surface Deformation Monitoring and Spatiotemporal Evolution Analysis of Open-Pit Mines Using Small-Baseline Subset and Distributed-Scatterer InSAR to Support Sustainable Mine Operations
by Zhouai Zhang, Yongfeng Li and Sihua Gao
Sustainability 2025, 17(19), 8834; https://doi.org/10.3390/su17198834 - 2 Oct 2025
Abstract
Open-pit mining often induces geological hazards such as slope instability, surface subsidence, and ground fissures. To support sustainable mine operations and safety, high-resolution monitoring and mechanism-based interpretation are essential tools for early warning, risk management, and compliant reclamation. This study focuses on the [...] Read more.
Open-pit mining often induces geological hazards such as slope instability, surface subsidence, and ground fissures. To support sustainable mine operations and safety, high-resolution monitoring and mechanism-based interpretation are essential tools for early warning, risk management, and compliant reclamation. This study focuses on the Baorixile open-pit coal mine in Inner Mongolia, China, where 48 Sentinel-1 images acquired between 3 March 2017 and 23 April 2021 were processed using the Small-Baseline Subset and Distributed-Scatterer Interferometric Synthetic Aperture Radar (SBAS-DS-InSAR) technique to obtain dense and reliable time-series deformation. Furthermore, a Trend–Periodic–Residual Subspace-Constrained Regression (TPRSCR) method was developed to decompose the deformation signals into long-term trends, seasonal and annual components, and residual anomalies. By introducing Distributed-Scatterer (DS) phase optimization, the monitoring density in low-coherence regions increased from 1055 to 338,555 points (approximately 321-fold increase). Deformation measurements at common points showed high consistency (R2 = 0.97, regression slope = 0.88; mean rate difference = −0.093 mm/yr, standard deviation = 3.28 mm/yr), confirming the reliability of the results. Two major deformation zones were identified: one linked to ground compaction caused by transportation activities, and the other associated with minor subsidence from pre-mining site preparation. In addition, the deformation field exhibits a superimposed pattern of persistent subsidence and pronounced seasonality. TPRSCR results indicate that long-term trend rates range from −14.03 to 14.22 mm/yr, with a maximum periodic amplitude of 40 mm. Compared with the Seasonal-Trend decomposition using LOESS (STL), TPRSCR effectively suppressed “periodic leakage into trend” and reduced RMSEs of total, trend, and periodic components by 48.96%, 93.33%, and 89.71%, respectively. Correlation analysis with meteorological data revealed that periodic deformation is strongly controlled by precipitation and temperature, with an approximately 34-day lag relative to the temperature cycle. The proposed “monitoring–decomposition–interpretation” framework turns InSAR-derived deformation into sustainability indicators that enhance deformation characterization and guide early warning, targeted upkeep, climate-aware drainage, and reclamation. These metrics reduce downtime and resource-intensive repairs and inform integrated risk management in open-pit mining. Full article
(This article belongs to the Special Issue Application of Remote Sensing and GIS in Environmental Monitoring)
Show Figures

Figure 1

25 pages, 8488 KB  
Article
Limestone-Based Hybrid Passive Treatment for Copper-Rich Acid Mine Drainage: From Laboratory to Field
by Joshua Pascual Pocaan, Brian Gerald Bueno, Jaica Mae Pagaduan, Johara Capingian, Michelle Airah N. Pablo, Jacob Louies Rohi W. Paulo, Arnel B. Beltran, Aileen H. Orbecido, Renan Ma. Tanhueco, Carlito Baltazar Tabelin, Mylah Villacorte-Tabelin, Vannie Joy T. Resabal, Irish Mae Dalona, Dennis Alonzo, Pablo Brito-Parada, Yves Plancherel, Robin Armstrong, Anne D. Jungblut, Ana Santos, Paul F. Schofield, Richard Herrington and Michael Angelo B. Promentillaadd Show full author list remove Hide full author list
Minerals 2025, 15(10), 1043; https://doi.org/10.3390/min15101043 - 1 Oct 2025
Abstract
Acid mine drainage (AMD) is an environmental concern that needs to be addressed by some mining industries because of its high concentrations of metals and acidity that destroy affected ecosystems. Its formation typically persists beyond the operating life of a mine site. Its [...] Read more.
Acid mine drainage (AMD) is an environmental concern that needs to be addressed by some mining industries because of its high concentrations of metals and acidity that destroy affected ecosystems. Its formation typically persists beyond the operating life of a mine site. Its management is even more challenging for sites that are abandoned without rehabilitation. In this study, a legacy copper–gold mine located in Sto. Niño, Tublay, Benguet, Philippines, generating a copper- and manganese-rich AMD (Cu, maximum 17.2 mg/L; Mn, maximum 2.90 mg/L) at pH 4.59 (minimum) was investigated. With its remote location inhabited by the indigenous people local community (IPLC), a novel limestone-based hybrid passive treatment system that combines a limestone leach bed (LLB) and a controlled modular packed bed reactor (CMPB) has been developed from the laboratory and successfully deployed in the field while investigating the effective hydraulic retention time (HRT), particle size, and redox conditions (oxic and anoxic) in removing Cu and Mn and increasing pH. Laboratory-scale and pilot-scale systems using simulated and actual AMD, respectively, revealed that a 15 h HRT and both oxic and anoxic conditions were effective in treating the AMD. Considering these results and unsteady conditions of the stream in the legacy mine, a hybrid multi-stage limestone leach bed and packed bed were deployed having variable particle size (5 mm to 100 mm) and HRT. Regular monitoring of the system showed the effective removal of Cu (88.5%) and Mn (66.83%) as well as the increase of pH (6.26), addressing the threat of AMD in the area. Improvement of the lifespan of the system needs to be addressed, as issues of Cu-armoring were observed, resulting in reduced performance over time. Nonetheless, the study presents a novel technique in implementing passive treatment systems beyond the typical treatment trains reported in the literature. Full article
Show Figures

Graphical abstract

16 pages, 2193 KB  
Article
Microscopic Mechanism of Moisture Affecting Methane Adsorption and Desorption in Coal by Low-Field NMR Relaxation
by Qi Li, Lingyun Zhang, Jiaqing Cui, Guorui Feng, Zhiwei Zhai and Zhen Li
Processes 2025, 13(10), 3113; https://doi.org/10.3390/pr13103113 - 28 Sep 2025
Abstract
Moisture in coal seams significantly impacts methane adsorption/desorption, yet its microscopic mechanism in intact coal remains poorly characterized due to methodological limitations. This study introduces a novel approach that integrates low-field nuclear magnetic resonance (LF-NMR) with volumetric analysis to quantify, in real-time, the [...] Read more.
Moisture in coal seams significantly impacts methane adsorption/desorption, yet its microscopic mechanism in intact coal remains poorly characterized due to methodological limitations. This study introduces a novel approach that integrates low-field nuclear magnetic resonance (LF-NMR) with volumetric analysis to quantify, in real-time, the effect of moisture on methane dynamics in intact coal samples. The results quantitatively demonstrate that micropores (relative specific surface area > 700 m2/cm3) are the primary adsorption sites, accounting for over 95% of the stored gas. Moisture drastically reduces the adsorption capacity (by ~72% at 0.29 MPa and ~57% at 1.83 MPa) and inhibits the desorption process, evidenced by a strong linear decrease in desorption ratio (DR) (R2 = 0.906) and a sharp exponential drop in the initial desorption rate (R2 = 0.999) with increasing moisture content. The findings provide a mechanistic understanding that is crucial for optimizing coalbed methane (CBM) recovery and enhancing strategies for outburst prevention and methane emission mitigation. The results reveal distinct adsorption and desorption features of intact coal compared with coal powder, which can be useful in total methane utilization and mining safety enhancement. Full article
Show Figures

Graphical abstract

22 pages, 2664 KB  
Article
The Potential and Usage of the Architectural Heritage of Mining Sites: Case Studies in the Locality of Rudňany, Slovakia
by Ján Ilkovič and Ľubica Ilkovičová
Buildings 2025, 15(19), 3468; https://doi.org/10.3390/buildings15193468 - 25 Sep 2025
Abstract
The aim of conversion is to reveal the potential of non-functioning buildings for transformation—i.e., to design a new life for them. A large number of original and presently non-functioning industrial production buildings are connected to mining activity. The subject of this study and [...] Read more.
The aim of conversion is to reveal the potential of non-functioning buildings for transformation—i.e., to design a new life for them. A large number of original and presently non-functioning industrial production buildings are connected to mining activity. The subject of this study and area of investigation are selected mining networks from the second half of the 20th century in the Rudňany settlement, which is located in the Spiš region. The aim of the research is to form a process algorithm for the reuse of areas and objects of mining activity and to highlight the cultural values, constructional substance, and preconditions for their further development. Part of the investigation comprises proposals for a new functional usage of the structures that will encompass the complex historical ground-points of the locality and include its historical roots and trends in the region’s social development and community. The quantitative and qualitative research is based on an analysis of the values of such structures based on traditional mining activity, accompanied by landscape research of the specific locality. The results are presented in the form of case studies oriented towards the identification and evaluation of the attributes of change for novel exploitation of the mining sites. The conclusion of the research is composed of an evaluation and interpretation feasibility study pointing out suitable solutions and preconditions for the sustainability of the converted mining structures as parts of open concepts for mining theme parks. Full article
(This article belongs to the Section Architectural Design, Urban Science, and Real Estate)
Show Figures

Figure 1

17 pages, 2233 KB  
Article
On-the-Ground Application of Cloud Evaluation: Big Data Reveals Experiential Effectiveness of Industrial Heritage Revitalization
by Xuesen Zheng, Timothy Heath and Sifan Guo
Appl. Sci. 2025, 15(19), 10388; https://doi.org/10.3390/app151910388 - 24 Sep 2025
Viewed by 14
Abstract
Post-occupancy evaluation is a critical mechanism for ensuring the sustained success and continuous improvement of industrial heritage revitalization initiatives. The quality of the visitor experience plays a key role in determining a project’s long-term vitality. This study focuses on assessing user satisfaction with [...] Read more.
Post-occupancy evaluation is a critical mechanism for ensuring the sustained success and continuous improvement of industrial heritage revitalization initiatives. The quality of the visitor experience plays a key role in determining a project’s long-term vitality. This study focuses on assessing user satisfaction with a revitalized industrial heritage site by employing web crawling and data mining techniques to systematically collect and analyze user-generated reviews from major online platforms. Using the 1933 Old Millfun in Shanghai, China, as an example, this research identifies six core evaluation dimensions derived from extensive user commentary: project accessibility, cultural legibility, aesthetic distinctiveness, commercial appeal, facility completeness, and sense of security. These dimensions are integrated into a comprehensive analytical framework, with the Fuzzy Comprehensive Evaluation (FCE) method applied to quantitatively assess the site’s performance across each category. By combining qualitative sentiment data with quantitative evaluation techniques, the data-driven presentation provides nuanced insights into the evolving user experience. The research results contribute to the development of a replicable and scalable paradigm for measuring user experience in industrial heritage revitalization and highlights the potential of digital platforms as valuable tools for heritage site management and continuous optimization. Full article
(This article belongs to the Special Issue Cultural Heritage: Restoration and Conservation)
Show Figures

Figure 1

28 pages, 3424 KB  
Article
Evaluation of Long-Term Environmental Impact and Radiological Risks at a Former Thorium and Rare Earth Site in North-Eastern Kazakhstan
by Zhanat Idrisheva, Iwona Ostolska, Ewa Skwarek, Gulzhan Daumova, Małgorzata Wiśniewska, Togzhan Toktaganov and Yernat Kozhakhmetov
Sustainability 2025, 17(19), 8569; https://doi.org/10.3390/su17198569 - 24 Sep 2025
Viewed by 52
Abstract
Kazakhstan holds the global leadership position in natural uranium mining. Nonetheless, the extraction and processing of radioactive ores has the potential to induce instances of radiological contamination. This study aimed to evaluate the radiological soil contamination at a former monazite, tin, and radioactive [...] Read more.
Kazakhstan holds the global leadership position in natural uranium mining. Nonetheless, the extraction and processing of radioactive ores has the potential to induce instances of radiological contamination. This study aimed to evaluate the radiological soil contamination at a former monazite, tin, and radioactive ore processing facility located in Ust-Kamenogorsk city. Pedestrian gamma–ray measurements revealed dose rates up to 1.00 µSv/h, significantly exceeding the natural background (0.16–0.18 µSv/h). The analysis of the 28 soil profiles demonstrated that deeper soil layers (below 60 cm) were significantly contaminated with radionuclides constituting production waste. Furthermore, the total activity in the superficial soil layer is in the range of 583–5275 Bq/kg (alpha emitters) and 641–1749 Bq/kg (beta radionuclides). The maximum of total radioactivity in the samples collected at the 80–100 cm layer was at the level of 22,482 Bq/kg (α-emitters) and 6845 Bq/kg for gross beta radiation. In consideration of the site’s proximity to public buildings, the calculated radiological hazard indices were calculated, revealing the potential danger for human health. The elevated excess lifetime cancer risk and annual gonadal dose equivalent obtained for the topsoil layer indicate a high level of radiological risk to the local population. The obtained results emphasise the necessity of developing rehabilitation strategies and long-term monitoring of the contaminated site, which is consistent with the global objectives of sustainable development in the field of environmental protection and public health. Full article
Show Figures

Figure 1

33 pages, 5199 KB  
Article
Sustainable Transformation of Post-Mining Areas: Discreet Alliance of Stakeholders in Influencing the Public Perception of Heavy Industry in Germany and Poland
by Anna Szewczyk-Świątek
Sustainability 2025, 17(19), 8567; https://doi.org/10.3390/su17198567 - 24 Sep 2025
Viewed by 120
Abstract
The sustainable transformation of areas associated with mining is an essential contemporary challenge. In the course of such transformations, economic benefits are confronted with community criticism of heavy industry. In this context, the study examines spatial solutions implemented in the revitalisation of areas [...] Read more.
The sustainable transformation of areas associated with mining is an essential contemporary challenge. In the course of such transformations, economic benefits are confronted with community criticism of heavy industry. In this context, the study examines spatial solutions implemented in the revitalisation of areas adjacent to active industrial sites. The article aims to characterise solutions applied in locations that elude a straightforward division into industrial and post-industrial. The motivations of the entities involved in the construction and the effects of implementing such projects are investigated. To achieve this aim, compositional and visual linkages in four locations (in Germany and Poland) were analysed, along with the intentions of designers and investors and the opinions of users. The study revealed the influence of political decisions on spatial solutions, an aspect not previously analysed, which has led to a limited understanding of the role they play in the transformation. It was indicated that drawing users’ attention to the aesthetic values of active industrial areas coincides with diverting attention from their nuisances. The discreet cooperation between local authorities, designers, and industry (as expressed in architectural solutions) was emphasised. The research opens a field for discussion on managing community perceptions through spatial solutions. Full article
(This article belongs to the Special Issue Sustainability and Innovation in Engineering Education and Management)
Show Figures

Figure 1

18 pages, 1236 KB  
Review
The Current State of Knowledge About Changes in the Synthesis of the Secondary Metabolites Caused by Habitat Conditions and Microbial Activity
by Barbara Bacler-Żbikowska, Agnieszka Hutniczak, Barbara Pilawa, Ewa Chodurek, Magdalena Zdybel, Anna Piekarska-Stachowiak, Dewi Fatmawati, Leszek Malinowski and Gabriela Woźniak
Agronomy 2025, 15(10), 2251; https://doi.org/10.3390/agronomy15102251 - 23 Sep 2025
Viewed by 209
Abstract
This comprehensive review paper describes how stressful environmental conditions affect the amounts and types of secondary metabolites synthetized by plants, with particular emphasis on plants that spontaneously grow on post-mining sites. Secondary metabolites are compounds that are not directly necessary for the performance [...] Read more.
This comprehensive review paper describes how stressful environmental conditions affect the amounts and types of secondary metabolites synthetized by plants, with particular emphasis on plants that spontaneously grow on post-mining sites. Secondary metabolites are compounds that are not directly necessary for the performance of basic life functions by plants but play an important role in the protection against adverse biotic and abiotic factors. Stress conditions stimulate the synthesis of secondary metabolites. The challenging post-mining sites are spontaneously colonized by many plant species, including medical plants. This observation inspired us to conduct the present review study. Apart from the abiotic conditions, the synthesis of secondary metabolites is also influenced by symbionts such as mycorrhizal fungi. A common effect of abiotic stressors is oxidative damage caused by reactive oxygen species (ROS). Metabolites such as antioxidants maintain the level of ROS at a level safe for the organism. This article presents the current state of knowledge about the impact of habitat conditions on the synthesis of secondary metabolites, which could impact the plant species growing spontaneously in post-mining areas. It considers the possibility of using such post-mining, mineral habitats to enhance these physiological mechanisms for synthesizing secondary metabolites. Full article
Show Figures

Figure 1

39 pages, 11616 KB  
Article
Integrating Advanced Technologies for Environmental Valuation in Legacy Mining Sites: The Role of Digital Twins at Lavrion Technological and Cultural Park
by Miguel Ángel Maté-González, Cristina Sáez Blázquez, Sergio Alejandro Camargo Vargas, Fernando Peral Fernández, Daniel Herranz Herranz, Enrique González González, Vasileios Protonotarios and Diego González-Aguilera
Sensors 2025, 25(19), 5941; https://doi.org/10.3390/s25195941 - 23 Sep 2025
Viewed by 264
Abstract
The rehabilitation of mining environments poses significant challenges due to the contamination risks associated with hazardous materials, such as arsenic and other chemical products. This research study presents the development of a Digital Twin for the Lavrion Technological and Cultural Park (LTCP), a [...] Read more.
The rehabilitation of mining environments poses significant challenges due to the contamination risks associated with hazardous materials, such as arsenic and other chemical products. This research study presents the development of a Digital Twin for the Lavrion Technological and Cultural Park (LTCP), a former mining and metalworking site that is currently undergoing environmental restoration. The Digital Twin integrates advanced technologies, including real-time sensor monitoring, geophysical methods, and 3D modeling, to provide a comprehensive tool for assessing and managing the environmental conditions of the site. Key elements of the project include the monitoring of hazardous-waste storage, the evaluation of contaminated soils, and the assessment of the Park’s infrastructure, which includes both deteriorating buildings and successfully restored structures. Real-time sensor data are collected to track critical parameters such as conductivity, temperature, salinity, and levels of pollutants, enabling proactive environmental management and mitigation of potential risks. The integration of these technologies enables continuous monitoring, historical data analysis, and improved decision making in the ongoing efforts to preserve the site’s ecological integrity. This study demonstrates the potential of using Digital Twins as an innovative solution for the sustainable management and valorization of mining heritage sites, offering insights into both technological applications and environmental conservation practices. Full article
(This article belongs to the Section Environmental Sensing)
Show Figures

Graphical abstract

17 pages, 3940 KB  
Article
Research on the Prediction of Liquid Injection Volume and Leaching Rate for In Situ Leaching Uranium Mining Using the CNN–LSTM–LightGBM Model
by Zhifeng Liu, Zirong Jin, Yipeng Zhou, Zhenhua Wei and Huanyu Zhang
Processes 2025, 13(9), 3013; https://doi.org/10.3390/pr13093013 - 21 Sep 2025
Viewed by 177
Abstract
In traditional in situ leaching (ISL) uranium mining, the injection volume depends on technicians’ on-site experience. Therefore, applying artificial intelligence technologies such as machine learning to analyze the relationship between injection volume and leaching rate in ISL uranium mining, thereby reducing human factor [...] Read more.
In traditional in situ leaching (ISL) uranium mining, the injection volume depends on technicians’ on-site experience. Therefore, applying artificial intelligence technologies such as machine learning to analyze the relationship between injection volume and leaching rate in ISL uranium mining, thereby reducing human factor interference, holds significant guiding importance for production process control. This study proposes a novel uranium leaching rate prediction method based on a CNN–LSTM–LightGBM fusion model integrated with an attention mechanism. Ablation experiments demonstrate that the proposed fusion model outperforms its component models across three key metrics: Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), and Root Mean Square Error (RMSE). Furthermore, comparative experiments reveal that this fusion model achieves superior performance on MAE, MAPE, and RMSE metrics compared to six extensively utilized machine learning methods, including Multi-Layer Perceptron, Support Vector Regression, and K-Nearest Neighbors. Specifically, the model achieves an MAE of 0.085%, an MAPE of 0.833%, and an RMSE of 0.201%. This attention-enhanced fusion model provides technical support for production control in ISL uranium mining and offers valuable references for informatization and intelligentization research in uranium mining operations. Full article
(This article belongs to the Section AI-Enabled Process Engineering)
Show Figures

Figure 1

13 pages, 3522 KB  
Article
High-Purity Tungsten Oxide Production from Low-Grade Scheelite Concentrates at Pilot Plant Scale
by Javier Nieto, Lourdes Yurramendi, Javier Antoñanzas and Jose Luis Aldana
Metals 2025, 15(9), 1051; https://doi.org/10.3390/met15091051 - 20 Sep 2025
Viewed by 208
Abstract
Tungsten is a critical raw material with increasingly important industrial applications. It is primarily found in minerals such as scheelite and wolframite (0.5% W), which are extracted and processed at the mine site to produce a high-grade scheelite concentrate (60% W). This process [...] Read more.
Tungsten is a critical raw material with increasingly important industrial applications. It is primarily found in minerals such as scheelite and wolframite (0.5% W), which are extracted and processed at the mine site to produce a high-grade scheelite concentrate (60% W). This process results in significant tungsten losses in the form of tailings, currently not utilized at the EU level. Deep eutectic solvents and imidazolium-based ionic liquids have been shown to possess excellent utility for recovering tungsten from low-grade concentrates, achieving tungsten oxide (96% purity) at high global yields (80%). In this study, an optimized ionic liquid-based process (involving leaching, solvent extraction, crystallization, and calcination) was developed at the laboratory scale. Important issues such as solvent flammability or the commercial availability of ionic liquids were addressed to ensure the safety and industrial feasibility of the process. Furthermore, a pilot plant was designed, constructed, and operated for a significant period (3 days). Tungsten oxide was produced with improved purity (>99%) and global yield (91.6%) in continuous operation. Full article
Show Figures

Figure 1

22 pages, 2891 KB  
Article
Distribution and Temporal Variations in Negative Pressure Along the Length of the Borehole During Directional Long Drilling
by Jun Liu, Qinghua Zhang and Jianwei Wang
Processes 2025, 13(9), 3001; https://doi.org/10.3390/pr13093001 - 20 Sep 2025
Viewed by 229
Abstract
Pre-extraction gas technology is commonly used in coal mines to extract gas from single coal seams, initial protective layers, and both unprotected and protected coal seams. With the development of drilling equipment, directional long drilling, pre-extraction, coal seam gas technology has been widely [...] Read more.
Pre-extraction gas technology is commonly used in coal mines to extract gas from single coal seams, initial protective layers, and both unprotected and protected coal seams. With the development of drilling equipment, directional long drilling, pre-extraction, coal seam gas technology has been widely applied, and negative pressure extraction is one of the key factors affecting the effectiveness of directional long drilling gas extraction. In order to determine the reasonable length of directional long boreholes, studying the negative pressure distribution and time-varying rules within such boreholes is of great significance for guiding later borehole layout and gas extraction. The COMSOL Multiphysics software v.5.3. was used to couple and solve the dynamic model of temperature, stress, and seepage in coal-containing gas, as well as the mathematical model of negative pressure attenuation in directional long boreholes. The gas pressure distribution in the coal surrounding the directional long borehole and the distribution and time-varying law of negative pressure in the borehole were studied. Then, the distribution and time-varying law of negative pressure in directional long borehole extraction were tested on site. Research has shown that the negative pressure attenuation during directional long drilling has a relatively small impact on the effectiveness of coal gas extraction, while the negative pressure at the hole opening is the key factor affecting the effectiveness of gas extraction. In the early stage of extraction, as the drilling depth increases, the pressure loss inside the hole increases and the negative pressure inside the hole decreases. As the extraction time becomes longer, the pressure loss inside the borehole decreases and the negative pressure inside the borehole gradually returns to the negative pressure value at the orifice. The gas flow velocity inside the extraction borehole gradually increases from the bottom of the hole to the hole opening, and the flow velocity at the bottom of the hole remains basically constant. The gas flow velocity inside the hole gradually decreases with the extension of extraction time, and the smaller the distance from the extraction hole opening, the greater the flow attenuation. The collapse of drilling holes during extraction affects the attenuation of negative pressure inside the hole in the short term. As the extraction time increases, the impact of the collapse on the negative pressure inside the hole is limited. The temperature of coal can significantly affect the negative pressure and gas flow distribution inside the pores. Considering the temperature effect, the gas flow velocity inside the pores is higher and the pressure loss is lower in the short term. On-site tests have determined that the depth of ultra-long directional drilling holes is shallower than 327 m, and the negative pressure changes inside the borehole are not significantly different from the negative pressure at the hole opening. The negative pressure stabilization speed near the hole opening and bottom is fast, usually reaching its peak within 3–10 min. The negative pressure stabilization process from the borehole opening to the hole bottom shows a “fast slow fast” trend. When using double-sided extraction, the time for negative pressure to reach stability is significantly shortened compared to single-sided extraction, and double-sided extraction is beneficial for improving the effectiveness of coalbed methane extraction. Full article
(This article belongs to the Special Issue Circular Economy on Production Processes and Systems Engineering)
Show Figures

Figure 1

16 pages, 1471 KB  
Article
Fish Alone Are Not Enough: Zoobenthos Improves Water Quality Assessment in Impacted Rivers
by Ionuț Stoica, Karina P. Battes, Anca-Mihaela Șuteu Ciorca and Mirela Cîmpean
Fishes 2025, 10(9), 467; https://doi.org/10.3390/fishes10090467 - 19 Sep 2025
Viewed by 366
Abstract
This study examines fish communities in the heavily impacted Bistrița River, located in the Eastern Carpathians of Romania, where diffuse pollution from mining, domestic wastewater, agricultural and forestry activities emerged as the most severe pressures. Fish sampling was conducted at twenty sites across [...] Read more.
This study examines fish communities in the heavily impacted Bistrița River, located in the Eastern Carpathians of Romania, where diffuse pollution from mining, domestic wastewater, agricultural and forestry activities emerged as the most severe pressures. Fish sampling was conducted at twenty sites across two Natura 2000 protected areas. Results showed that species richness and diversity were higher downstream (Z1–Z5), indicating improved ecological conditions compared to the upstream section (B1–B15). The fish-based Index of Biological Integrity (IBI) suggested overall good biological integrity, with excellent conditions (class I) recorded in 70% of sites. Redundancy analysis (RDA) further revealed that elevation and conductivity significantly shaped community structure, while the site-specific impact score had only marginal effects. To assess water quality and biotic integrity based on different communities, as required by the Water Framework Directive (WFD), five sites were selected for parallel sampling of diatoms and benthic invertebrates. Among these, zoobenthos proved the most sensitive to water quality degradation, with biotic indices indicating classes I to III. These findings demonstrate that assessments based solely on fish may underestimate ecological impacts, underscoring the need for complementary approaches that account for multiple biotic communities when monitoring riverine ecosystem health. Full article
(This article belongs to the Special Issue Toxicology of Anthropogenic Pollutants on Fish)
Show Figures

Graphical abstract

Back to TopTop