Green Mining Research Articles

Optimizing open-pit coal mining operations: Leveraging meteorological conditions for dust removal and diffusion

Dust pollution from Chinese open-pit coal mines (OPCMs) threatens the coexistence of resource development and environmental protection. This research introduces a new approach to designing OPCMs based on meteorological indicators for dust removal and diffusion. It analyzes the production, distribution, and dust emission features of large-scale OPCMs in China. The factors affecting dust dispersion and atmospheric pollution characteristics were also examined. The findings reveal a surge in the number and output of OPCMs, intensifying the conflict between resource development and environmental protection. Notably, over 80% of OPCMs are in arid and semi-arid regions, exacerbating the challenge. Microclimate effects, including circulation and inversion effects, further amplify dust pollution. Regional and seasonal dust pollution patterns were identified, with the southern region experiencing the highest pollution levels, followed by the northern and central regions. Seasonally, dust pollution exhibits the following pattern: winter > autumn > spring > summer. An alarming decline in atmospheric self-cleaning capacity over the past two decades underscores the pressing challenges ahead for dust control. The increase in air stagnation days/events highlights the urgency for effective dust prevention and control measures. This research suggests considering meteorological elements in OPCM design for dust control. Optimizing mining operations based on weather forecasts enables the utilization of natural conditions for effective dust prevention and control. The results provide insights for dust prevention and control in open-pit mines to foster green and climate-smart mining.

Analysis of Land Reclamation Policy and Green Mining Technology on Ecosystem Stability and Mine Productivity in Kalimantan, Indonesia

This study examines the effects of Green Mining Technology and Land Reclamation Policy on Ecosystem Stability and Mine Productivity in Kalimantan, Indonesia. Using structural equation modeling (SEM) with Partial Least Squares (PLS), data from a sample of mining operations were analyzed to test hypotheses regarding these relationships. Results indicate significant positive relationships between both Green Mining Technology and Land Reclamation Policy with Ecosystem Stability and Mine Productivity. The findings underscore the dual benefits of sustainable practices and policy interventions in enhancing environmental sustainability and economic productivity in mining operations.

Technology is key to green coal mining

Technology is key to green coal mining

Knowledge synthesis on the mine life cycle and the mining value chain to address climate change

The escalating demands for mineral commodities driven by population growth and energy transition are prompting the mining industry to intensify extraction efforts and respond to the imperatives of climate change. Concurrently, the pressure of climate change-related concerns necessitates mining operations to enhance their environmental, economic, and social sustainability. This review aims to synthesize the overlapping knowledge from the mine life cycle (MLC) and the mining value chain (MVC) to distill the practices and strategies for mining's climate action as an extended producer responsibility. The first focus of this study was to examine the concepts of MLC and MVC and their interconnections. Subsequently, an in-depth literature review was conducted to map each stage of the MLC to the value chain regarding mining's climate action and future requirements. Our work pinpointed specific climate-related challenges and opportunities at every juncture, underscoring the importance of strategic mine planning with climate objectives, design for closure, renewables deployment, green mining technologies, agile and lean operations, risk mitigation for premature mine closure, and climate information transparency.

Galvanic interaction between galena and pyrite with dithiothreitol and its effects on flotation performance

With the advancement of green mine construction and the increasing difficulty of lead–sulphur resources, the traditional lime high-alkalinity lead–sulphur separation technology has exposed many shortcomings. In this study, based on the galvanic interaction of galena and pyrite, an environmental-friendly depressant dithiothreitol (DTT) was used to separate pyrite and galena under low alkalinity. In addition, the mechanism of DTT was revealed by electrochemical, ion dissolution, contact angle, zeta potential and DFT calculation. The results indicated that the galvanic interaction between galena and pyrite promoted the oxidation of galena and the dissolution of Pb2+ from the surface of galena, and Pb2+ would be adsorbed on the pyrite surface and increase the floatability of pyrite. DTT could selectively depress pyrite at low alkalinity. The interaction mechanism of DTT was that DTT could weaken the galvanic interaction of galena and pyrite and complex lead ions. In addition, DTT was adsorbed on the pyrite surface through the Fe-S bond, and the pre-adsorbed DTT hindered the adsorption of DDTC on the pyrite surface, thus the pyrite flotation was depressed.

Advancing toward sustainability: The emergence of green mining technologies and practices

This study comprehensively evaluates the integration and effectiveness of green mining technologies within the mining sector, specifically focusing on mitigating the environmental impact of traditional mining practices. The primary goal is to establish a sustainable mining model that significantly reduces energy consumption and minimizes ecological disturbances. To achieve this, the study employs a mixed-method approach, integrating quantitative data analysis from monitored mining sites and qualitative insights from industry experts. Key parameters include energy consumption, greenhouse gas emissions, and reductions in chemical use. The findings reveal that effective integration of green mining technologies leads to significant reductions in greenhouse gas emissions, lower energy consumption, and improved waste management compared to traditional methods. Specifically, the use of electric vehicles and renewable energy sources in mining operations has resulted in decreased carbon emissions and energy usage across studied sites. The research concludes that green mining practices, when supported by robust technological integration and regulatory frameworks, not only enhance environmental sustainability but also boost economic efficiency within the mining industry. This study recommends increased investment in the research and development of green technologies and calls for tighter regulatory oversight to ensure the widespread adoption and optimization of these practices.

Promoting Sustainable Coal Gas Development: Microscopic Seepage Mechanism of Natural Fractured Coal Based on 3D-CT Reconstruction

Green mining is an effective way to achieve sustainable development in the coal industry. Preventing coal and gas outburst dynamic disasters are essential for ensuring sustainable and safe mining. The numerous microscopic pores within the coal serve as the primary storage space for gas, making it critical to explore the structural distribution and seepage characteristics to reveal the disaster mechanism. Under mining stress, gas within the micropores of the coal migrates outward through cracks, with these cracks exerting a significant control effect on gas migration. Therefore, this study focuses on utilizing natural fractured coal bodies as research objects, employing a micro-CT imaging system to conduct scanning tests and digital core technology to reconstruct sample pore and fracture structures in three dimensions, and characterizing the pores, cracks, skeleton structure, and connectivity. A representative elementary volume (REV) containing macro cracks was selected to establish an equivalent model of the pore network, and a seepage simulation analysis was performed using the visualization software. Revealing the seepage characteristics of fractured coal mass from a microscopic perspective. The research results can provide guidance for gas drainage and dynamic disaster early warning in deep coal mines, thus facilitating the sustainable development of coal mining enterprises.

Research on the Dust Transport Law in Large Mining Height Fully Mechanized Mining Face

The fully mechanized mining face with high mining height has always been a high-risk area for coal mine dust pollution. In order to further understand the spatiotemporal transport law of dust in the zoning of the high mining height fully mechanized mining face, the 122109 high mining height fully mechanized mining face of Caojiatan Coal Mine was taken as the research object. Numerical simulation method was used to simulate and analyze the dust transport situation of the 122109 fully mechanized mining machine drum single dust source, the hydraulic support moving frame single dust source, and the superposition of all dust sources in forward and backward wind cutting coal. The research results can guide the ventilation layout design in the early stage of the mine and the dust control in the comprehensive mining process, which is of great significance for the construction of safe and green mines.

Experimental investigation on dynamic deformation characteristics of the overlying strata in backfilling strip mining at different time scales.

The dynamic subsidence disaster caused by underground mining of coal resources is a complex spatiotemporal process, which is a common disaster in mining areas. The backfilling strip mining technology is a green and sustainable coal mining method, which has been commonly used to reduce the subsidence disaster of the overlying strata and protect surface buildings. The transient deformation is the main reason of surface buildings damage; therefore, in this study, the similar material model was used to research dynamic deformation characteristics of the overlying strata in backfilling strip mining at different time scales, and the optical image method was employed to monitor and obtain the movement data of the overlying strata automatically. The data analysis shows that there is a time-scale effect in mining subsidence. The deformation of the overlying strata increases instantaneously at a certain time under the monitoring of small time scale, and this phenomenon gradually disappears as time scales increase. According to the subsidence velocity of small time scale, the subsidence state of the overlying strata can be further divided into the abrupt subsidence state and the gentle subsidence state. This is really significant for promoting the development of the backfilling strip mining technology and preventing the damage of surface buildings.

The basic characteristics of paste backfill materials based on highly active mineral admixtures: Part I. Preliminary study on flow, mechanics, hydration and microscopic properties

The cost performance of backfill materials in coal mines has long limited the widespread use of backfill technology. Therefore, developing backfill materials that are both cost-effective and high-performing is a pressing scientific issue that requires immediate attention. This study proposes replacing ordinary Portland cement (OPC) with highly active mineral admixtures, such as mineral powder and limestone powder, to prepare a green, low-cost, and high-performance coal mine backfill material. The use of mineral admixtures can improve the performance of the backfill material while reducing its environmental impact. The proposed approach is cost-effective and environmentally friendly. The study employed experimental tests and microscopic characterization methods, such as the slump test, hydration heat test, uniaxial compressive strength test, and microstructure test, to clarify the synergistic reaction mechanism of highly active mineral admixture-based paste backfill material (HAM-PBM). This clarification is helpful in regulating the macroscopic properties of hardened paste. The results show that: (1) The rheological properties of fresh HAM-PBM slurry are consistent with the Herschel-Bulkley model, and its fluidity meets the technical requirements for coal mine backfilling. The slump of fresh HAM-PBM slurry ranges from 140 to 145 mm, and the yield stress ranges from 3.188 to 12.819 Pa. (2) Highly active mineral admixtures significantly affect the early hydration process of HAM-PBM. The parameters of the hydration characteristics during the initial dissolution stage, acceleration stage, deceleration stage, and stabilization stage gradually decrease, while the duration of the induction stage gradually increases. This confirms that the early hydration activity of mineral powder (MP) and limestone powder (LF) is lower than that of OPC. (3) The uniaxial compressive strength (UCS) of the MP series exhibits an "anti-hook" change pattern, while the UCS of the LF series shows a decreasing change pattern. The microstructure, including the number of hydration products, microscopic density, and other characteristics, follows the same change pattern as the UCS. (4) Based on the synergistic reaction mechanism of hardened slurry, it is recommended that MP replace a maximum of 10 % of OPC and LF replace a maximum of 5 % of OPC. The need for composite replacement of OPC with MP and LF is clarified, resulting in a cost-effective coal mine backfill material. This study has contributed to the national "double carbon" policy and the low-cost backfilling application of coal mines.

Study on physical and mechanical properties of oil shale ash–based green mining filling materials

Study on physical and mechanical properties of oil shale ash–based green mining filling materials

Research hotspots and development trends of green coal mining: Exploring the path to sustainable development of coal mines

Coal mining and utilization should not only ensure safety and efficiency, but also form the theory and technology of green coal as soon as possible to guide the sustainable development of coal mines. In order to grasp the overall research progress of the theme of green coal mining (GCM), with coal mining as the main line and ecological environment issues as the link, 730 articles in the Web of Science database from 2004 to 2023 were visually analyzed by VOSviewer. Draw a knowledge map of research areas, countries, affiliations, authors and hot keywords, and discuss the research hotspots and trends of the GCM. The results show that GCM has gone through three periods: initial period, slow period and rapid period. China and the China University of Mining and Technology have become the core research country and the core affiliate of the GCM, respectively. The clustering analysis of research keywords can be divided into 8 main clusters. During the past 20 years, keywords such as backfilling, fly ash, green mine construction, paste material, energy transition, green economy, coal gasification and biotechnology have been the representative research hotspots in each cluster. With the progress of the times, the related policies, academic ideas and research hotspots of the GCM theme have the evolutionary characteristics of branching expansion, from shallow to deep, subject integration, decline and prosperity. On this basis, 5 key research directions in the future under the GCM theme are put forward, namely, intelligent green coal mining technology, green coordinated mining technology of coal and associated resources, green resource transformation and comprehensive utilization of abandoned mines, life cycle ecological restoration technology and energy development concept and research and development of new green coal-based materials. This study provides an effective path for the sustainable development of coal mines in the future.

Green nickel, electric vehicles and mining governance challenges in the U.S.

New critical metals mines are being prospected throughout the U.S. to meet the needs for batteries for electric vehicles, as well as solar and wind technologies. Mineral prospecting is meeting growing opposition from coast to coast, including Arizona, Idaho, California and Alaska. This article draws attention to the northern state of Minnesota where a complex social movement is emerging to challenge the devastating local contamination that might result from new “green nickel” mining. Focusing on Talon Metal's Tamarack project as a case study, the article describes how tribal communities and their social movement allies are challenging this green energy paradox through cultural, legal and political strategies.

Research on chlorine salt antifreeze road dust suppressants for open-pit coal mines

In addressing the significant challenge of trucking road dust emanating from open-cast coal mines, the prevalent method of conventional water sprinkling for dust removal on transport roads has proven suboptimal. This inadequacy is attributed to the pronounced mobility of truck transport roads, substantial dust loads, and extensive open dust sources. Particularly in cold mining regions, the use of water in winter exacerbates the issue by causing icy road surfaces, thereby increasing the risk of truck skidding and overturning, posing a severe hazard to both mine safety and the well-being of truck drivers. A pragmatic imperative exists to devise a solution that effectively addresses both anti-freezing and dust suppression in open-pit coal mine roads, while minimizing corrosive impact. Against the backdrop of Hebei Open-pit Coal Mine in Huolin, Inner Mongolia, this study focuses on the development of a chloride salt antifreeze-type road dust inhibitor tailored for open-pit transportation roads. The proprietary anti-freezing dust suppressant achieves a freezing point as low as −36.4 °C, exhibiting corrosion efficiency merely at 56.5% of that of water. Notably, the effective dust suppression duration surpasses that of water by a factor of 150, resulting in a 53% reduction in dust suppression costs. This innovation is specifically applicable to high-cold and arid surface coal mines in northern regions and similar mining contexts. It offers technical support for the establishment of environmentally sustainable practices in surface coal mines, representing a pivotal step toward the realization of green mining initiatives.

Genealogy of Green Mining in Europe and Asia

The green mining concept is a consequence of the world’s commitment to realizing sustainable economic development. This aims to maintain the availability of natural resources in the future by minimizing environmental and social damage due to mining. This article aims to explain the genealogy of green mining in Europe and Asia, as well as conditions encourage the formation of green mining regulations. This is important, considering that Indonesia has abundant natural resources and is committed to accelerating green economybased downstream programs. It is hoped that this study can become a preference for natural resource management, especially mining, that prioritizes sustainability. Our research used literature studies starting from searching, collecting, evaluating and analyzing relevant sources according to the research topic. We found that there were differences in the background to the emergence of the concept of green mining in Europe and Asia. Green mining in Europe stems from public awareness of climate change due to environmentally unfriendly mining processes. So, this awareness gives birth to environmentally friendly policies in the mining process. Meanwhile, in Asia, the emergence of green mining is caused by international policies that pressure countries in Asia both politically and economically to implement green mining. This shows that green mining is related to the geopolitical and geoeconomic spectrum.

Gangue grouting filling in subsequent space of coal green mining: methodology and case study

Underground backfilling stands out as a crucial technological strategy for the eco-friendly and effective management of solid waste in mining operations. However, existing backfilling techniques have led to increased production processes at the working face, resulting in a reduction in coal extraction efficiency. Addressing the temporal and spatial interference between mine solid waste backfilling and coal mining is essential. To overcome this challenge, this study introduces a novel post-mining spatial gangue slurry backfilling method. Radar detection was employed to ascertain the typical characteristics of the subsequent space collapse roof shape. Stress monitoring and compaction experiments were conducted to establish the relationship between stress and the bulking coefficient of the overlying rock mass, identifying subsequent spatial void structure characteristics. The development of a CO2 mineralized coal-based solid waste filling material, utilizing conventional low-calcium fly ash under normal temperature and pressure conditions, was presented. This paper provides a comprehensive understanding of the post-mining spatial gangue slurry backfilling method, outlines the spatial layout approach for the corresponding system, and analyzes research challenges associated with gangue slurry backfilling materials and the technology of slurry injection borehole layout. The research aims to innovate an efficient underground disposal model for gangue, contributing to the refinement of the technical system for the comprehensive disposal and utilization of gangue.

Seasonal distributions and possible sources of low molecular weight organic acids in PM2.5 from a typical mining city after decade green mining developing in Southeastern Hubei, Central China

Low molecular weight (LMW) organic compounds are prevalent in the atmospheric aerosols. Human activities and natural sources could significantly influence aerosol compositions and concentrations, particularly in a typical mining and metallurgy city. In this study, we measured dicarboxylic acids, ω-oxocarboxylic acids, pyruvic acid, α-dicarbonyls, and fatty acids in PM2.5 from Huangshi, China throughout one year. The results indicated that oxalic acid and glyoxylic acid were the most abundant dicarboxylic acid and ω-oxocarboxylic acid, respectively, across all seasons. Following nearly a decade of environmentally conscious economic development in Huangshi, it is observed that organic compounds primarily accumulated in PM2.5 due to the combustion of fossil fuels for mining-related activities and biogenic emissions. Furthermore, anthropogenic activities, including emissions related to traffic, biomass burning, and plastic incineration, significantly influence the composition of organic aerosols. Natural processes, such as atmospheric oxidation during long-distance transport, predominantly from North China, Mongolia, Russia, and Kazakhstan, also play a substantial role. The findings underscore the transitioning energy structures, modes of transport, and oxidation processes during long-distance transport have already begun to influence the composition of LMW organic compounds. The insights gained from this study offer valuable information for researchers and governmental authorities to understand the molecular composition and potential sources of LMW organic acids in the context of green mining development. This knowledge can aid in the formulation of targeted policies for the prevention and control of carbonaceous pollution in similar mining regions globally.

Exploration of the Application of Green Mining Technology in Coal Mines under the New Situation

This paper discusses the application of green mining technology in coal mines under the new situation, considering the environmental pressures and requirements for sustainable development faced by coal mining. Firstly, it introduces the definition and principles of green mining, along with its development history, and analyzes the importance of relevant policies and regulations. Subsequently, it analyzes the demands faced by coal mining under the new situation, including the relationship between environmental issues and sustainable development, the impact of new energy development on coal mines, and social demands and public opinion pressure. Furthermore, through application cases, it showcases the specific practices of green mining technology in coal mines, involving environmental protection technology, energy efficiency improvement technology, and green mining technology. When discussing the challenges and issues of technology application, it focuses on technical difficulties, economic feasibility, and human resources and training needs. Finally, it looks ahead to the prospects of green mining technology in coal mines, emphasizing the importance of sustainable development and proposing suggestions regarding technological innovation, policy support, and corporate responsibilities.

Ecological-Based Mining: A Coal–Water–Thermal Collaborative Paradigm in Ecologically Fragile Areas in Western China

A substantial reduction in groundwater level, exacerbated by coal mining activities, is intensifying water scarcity in western China’s ecologically fragile coal mining areas. China’s national strategic goal of achieving a carbon peak and carbon neutrality has made eco-friendly mining that prioritizes the protection and efficient use of water resources essential. Based on the resource characteristics of mine water and heat hazards, an intensive coal–water–thermal collaborative co-mining paradigm for the duration of the mining process is proposed. An integrated system for the production, supply, and storage of mining companion resources is achieved through technologies such as roof water inrush prevention and control, hydrothermal quality improvement, and deep-injection geological storage. An active preventive and control system achieved by adjusting the mining technology and a passive system centered on multi-objective drainage and grouting treatment are suggested, in accordance with the original geological characteristics and dynamic process of water inrush. By implementing advanced multi-objective drainage, specifically designed to address the “skylight-type” water inrush mode in the Yulin mining area of Shaanxi Province, a substantial reduction of 50% in water drillings and inflow was achieved, leading to stabilized water conditions that effectively ensure subsequent safe coal mining. An integrated-energy complementary model that incorporates the clean production concept of heat utilization is also proposed. The findings indicate a potential saving of 8419 t of standard coal by using water and air heat as an alternative heating source for the Xiaojihan coalmine, resulting in an impressive energy conservation of 50.2% and a notable 24.2% reduction in carbon emissions. The ultra-deep sustained water injection of 100 m3·h−1 in a single well would not rupture the formation or cause water leakage, and 7.87 × 105 t of mine water could be effectively stored in the Liujiagou Formation, presenting a viable method for mine–water management in the Ordos Basin and providing insights for green and low-carbon mining.

Influence of Mining Sequence of Branch on Stope Pressure Behaviour on Continuous Mining and Continuous Backfilling

Instability in coal pillars and filling bodies is a common occurrence during the mining process of continuous mining and continuous backfilling (CMCB). In view of this, combining numerical simulation, similarity simulation, and on-site testing approaches, backfill mining models were established in Flac3d5.01 software, similarity model test bench, and “two-stage”, “three-stage”, and “four-stage” mining sequences were conducted; the stress characteristics of coal pillar-filling body and the displacement evolution law of surrounding rock have been compared under three typical mining sequences. The results show that compared to two-stage mining sequence, three-stage and four-stage mining sequences provide sufficient time for the solidification of the filling body. The coal pillar exhibits better stability in the early stage of mining, but the stress concentration phenomenon is more significant in the later stage of mining. The stress concentration coefficient is the highest when the width of the coal pillar is 10 m. The integrity of the overburden is intact in different mining sequences, with only a small amount of separation and longitudinal cracks. Increasing the number of mining stages significantly reduces the roof subsidence, with the maximum roof subsidence in the three- and four-stage mining sequences being only 62.0% and 33.9% of that in the two-stage mining sequence. “Two stages”, “three stages”, and “four stages” of mining sequences are implemented in response to the requirements of weak and thick coal seam mining in Haoyuan Coal Mine and gangue disposal in Chahasu Coal Mine. Good engineering applications are achieved, enabling the realisation of safe, green, and efficient coal mining.