Search

Facing the complex coexistence of various metal ions in wastewater and mineral resources, metal–organic frameworks (MOFs) with diverse functionalities and tunable pores are poised to serve as distinctive solutions for efficiently recognizing and selectively separating radioactive thorium (Th(IV)). Herein, a fluorescent MOF (DBT‐DHTA‐Cd) with unique thorium nanocavity traps is rationally designed by using two rigid ligands, including azole and hydroxyl groups, respectively. Notably, the synergistic effect of the appropriate pore size and dense hydroxyl···N nanocavity traps in DBT‐DHTA‐Cd results in selective capture of Th(IV), arising from the high charge density of nano‐trap and extremely low binding energy (Eads = −602.7 KJ mol−1). The fast adsorption kinetics (30 min) and rapid fluorescence response (1 min) of DBT‐DHTA‐Cd toward Th(IV) are attributed to the stronger electron holding capacity of the d and f orbitals belonged to Th(IV), making it more prone to accepting electrons transferred from the N/O active sites in the nano‐trap. As a verification test, tailing breakthrough experiments confirm that DBT‐DHTA‐Cd can efficiently purify Th(IV) from monazite mining solid waste in one step. This work provides profound insights into relationship between structure and property of MOFs and has valuable guidance for designing materials in the radioactive purification field. [ABSTRACT FROM AUTHOR]

This article seeks to evaluate the scientific landscape of the phytoremediation of mine tailings through a series of bibliometric and scientometric techniques. Phytoremediation has emerged as a sustainable approach to remediate metal-contaminated mine waste areas. A scientometric analysis of 913 publications indexed in Web of Science from 1999 to 2023 was conducted using CiteSpace. The results reveal an expanding, interdisciplinary field with environmental sciences as the core category. Keyword analysis of 561 nodes and 2,825 links shows a focus on plant-metal interactions, microbial partnerships, bioavailability, and field validation. Co-citation analysis of 1,032 nodes and 2,944 links identifies seminal works on native species, plant-microbe interactions, and amendments. Temporal mapping of 15 co-citation clusters indicates a progression from early risk assessments and native plant inquiries to integrated biological systems, economic feasibility, and sustainability considerations. Recent trends emphasize multidimensional factors influencing adoption, such as plant-soil-microbe interactions, organic amendments, and field-scale performance evaluation. The findings demonstrate an intensifying translation of phytoremediation from scientific novelty to engineering practice. This quantitative and qualitative analysis of research trends aids in understanding the development of phytoremediation for mine tailings. The results provide valuable insights for researchers and practitioners in this evolving field. [ABSTRACT FROM AUTHOR]

This paper demonstrates the characteristics of soil-like material extracted from the landfill mining activity at the Ariyamangalam dump yard, located in Tiruchirappalli city of southern India. The landfill mining waste was collected and characterised for contaminant potential, thereby its suitability for reuse applications offsite. Soil-like materials of size fractions finer than 2 mm have been assessed for their physico-chemical characteristics and compared the acceptability criterion with the drinking standard IS 10500: 2012. Total soluble solids and closely associated parameters have been determined in the water extract from soil-like materials and local soils and compared with the international regulatory standards for reuse acceptability. From the total heavy metal concentration of soil-like material and local soil, three different pollution indices, namely contamination ratio, geo-accumulation index, and enrichment factor, have been identified and categorised soil-like material as low contaminated for lead; low to moderately contaminated for chromium, nickel, and iron; moderately contaminated for manganese; and moderately to strongly contaminated for copper and zinc. The organic and moisture content of soil-like material was reported as 22 and 19.6%, whereas the local soil showed 2.4 and 1.5%, respectively. Due to its enormous organic content, soil-like materials pose as less efficient in utilising offsite applications without primary treatment. [ABSTRACT FROM AUTHOR]

Rare earth elements (REEs) are essential for high-tech and low-carbon economies. Achieving global net-zero emissions by 2050 would require a significant increase in mineral input, including 3–7 times more REEs. At present, there are no direct high-grade ores of heavy REs like terbium. Bastnasite, monazite, and xenotime are the primary sources of terbium, while southern Chinese ion-adsorption clays are the richest commercial sources. To address the scarcity of rare earth resources, countries lacking RE deposits should focus on developing innovative and economically viable recycling techniques for the recovery of REs like terbium from different secondary resources. Spent fluorescent lamp phosphor powder represents a potential secondary resource for terbium recovery, although research efforts have been focused mostly on other REEs than Tb as value-added products. Hydrometallurgical processing is widely employed to extract terbium from different resources. The present review systematically summarizes in detail the major recovery/separation techniques used and critically evaluates the potential of terbium recovery from mineral resources and end-of-life fluorescent phosphor wastes. The advantages and limitations of each of these technologies have been provided. The objective is to foster valuable insights for researchers and the development of economical and promising extraction technologies for the recovery of terbium. [ABSTRACT FROM AUTHOR]

Open-pit mining generates significant amounts of waste material, leading to the formation of large waste dumps that pose environmental risks such as land degradation and potential slope failures. The paper presents a stability analysis of waste dump slopes in open-pit mining, focusing on the Motru coalfield in Romania. To assess the stability of these dumps, the study employs the Shear Strength Reduction Method (SSRM) implemented in the COMSOL Multiphysics version 6 software, considering both associative and non-associative plasticity models. (1) Various slope angles were analyzed, and the Factor of Safety (FoS) was calculated, showing that the FoS decreases as the slope angle increases. (2) The study also demonstrates that the use of non-associative plasticity leads to lower FoS values compared to associative plasticity. (3) The results are visualized through 2D and 3D models, highlighting failure surfaces and displacement patterns, which offer insight into the rock mass behavior prior to failure. (4) The research also emphasizes the effectiveness of numerical modeling in geotechnical assessments of stability. (5) The results suggest that a non-associative flow rule should be adopted for slope stability analysis. (7) Quantitative results are obtained, with small variations compared to those obtained by LEM. (6) Dilatation angle, soil moduli, or domain changes cause differences of just a few percent and are not critical for the use of the SSRM in engineering. [ABSTRACT FROM AUTHOR]

The mining activity is fundamental for human development, but it requires changes in the environment, negatively affecting soil organic carbon (SOC) stock. The only way to restore the original SOC stock is via rehabilitation practices. Considering adopting more efficient techniques and technologies for the rehabilitation process, this study aimed to assess SOC stock in rehabilitating iron minelands and to use remote sensing tools to predict it. The study was conducted in two waste piles (WP-W and WP-S4) each presenting a chronosequence (initial, intermediate, and advanced stages) in addition to the forest (reference), all located in the Carajás Mineral Province, southeastern Amazon, Brazil. Results showed a gradual increase in the SOC stock for the WP-S4 from the initial to the advanced stage (average of 26.5 Mg ha−1). There were no differences among the rehabilitation stages for the WP-W. The difference in SOC stocks between the two waste piles is mainly related to the soil fertility status, indicating a higher SOC accumulation potential for the WP-S4. Principal component analysis revealed that the attributes presenting major influence on the SOC stock are K, SOC, cation exchange capacity, B, and total N (positive); and soil bulk density, pH, and sand (negative). The regression model results showed that the remote sensing indices Normalized Difference Vegetation Index (NDVI) and Bare Soil Index (BSI) are useful to derive digital maps of SOC stock and assist in the monitoring of the rehabilitation in the waste piles of the iron mineland. [ABSTRACT FROM AUTHOR]

Mining waste creates challenging soil conditions that hinder tree establishment for boreal forest restoration. This study investigated the effects of adding topsoil or ramial chipped wood (RCW) on the physicochemical properties of waste rock and the growth and survival of planted native tree species. A randomized-block setup with four replications of four treatments was established on a gold mine site in western Quebec, Canada in 2018, and planted with Pinus banksiana and Abies balsamea. Results demonstrated that topsoil addition significantly improved height and diameter growth, aerial and root biomasses, survival, and nutrient uptake (N, P, and S) in conifer seedlings. Concomitantly, water content increased, pH lowered and nutrient concentrations increased in the substrate with a topsoil layer. However, multivariate analysis revealed that these improved soil conditions alone did not determine the survival and growth of conifer seedlings. In contrast, the application of RCW-based treatments had no discernible impact on the growth and survival of the planted trees. Additionally, topsoil amendment effectively reduced the concentration of potentially phytotoxic elements in soil and needles, particularly arsenic. The total arsenic concentration in the mineral substrate (84.1 to 507 µg.g− 1) emerged as a growth-limiting factor for both conifer species. The total concentration of arsenic in the waste rock correlated positively with arsenic accumulation in the tree needles, indicating potential root uptake of this element. This study emphasizes the significance of addressing arsenic availability during reclamation efforts at mine sites. Nonetheless, further research is required to determine the phytotoxic thresholds of arsenic on conifers and its potential metabolic effects. [ABSTRACT FROM AUTHOR]

Combining mine exhaust waste heat with existing heat pump technology is a promising technical route to realise the efficient extraction and scientific use of low-grade waste heat resources in mines and to solve the problem of insufficient heat supply in remote mining areas. This study proposes a new type of mine-exhaust-air heat exchange coupled with heat-pump waste-heat-utilisation system based on deep enthalpy heat extraction. Using a mining area in Northwest China as a representative case, this study establishes a systematic exergy analytical model and a thermo-economic model. Through an in-depth analysis of the different evaporation temperatures and condensing temperatures, the system's energy efficiency ratio (COP) reaches its optimal performance, with the total exergy efficiency surpassing 90%. The minimum efficiency of the subsystem return air heat exchanger is 35%. The unit thermal costs of the mine exhaust air waste heat utilisation system and a conventional coal-fired boiler system are 0.1291 and 0.1573 million RMB/kW·h, respectively. This is a thermal economics cost saving of 21%. The studied system demonstrates great economic viability and the potential for energy saving throughout its life cycle. [ABSTRACT FROM AUTHOR]

The linear economy follows the "take-make-dispose" model and generates huge amounts of waste without consideration for recycling or reuse. This model which deals with raw materials puts pressure on natural resources and creates a serious environmental impact. In a circular economy, the "reduce-reuse-recycle" model is applied to recycle waste into resources and reduce the impact on the environment and society. This work aims to highlight the significance of implementing a circular economy approach in the construction sector by merging two different production lines, notably mining activity and agri-food industry. The investigation presents sustainable management of coal mine waste (CMW) and olive pomace (OP) in the production of eco-friendly fired materials and introduces an innovative approach for manufacturing lightweight fired bricks. Microstructural, physical, mechanical, and thermal properties were determined to evaluate the technological quality of fired materials at 900 °C. As a pore-forming agent, adding 10 wt% OP yielded specimens with a bulk density of 1552 kg/m3, water absorption of 19.80%, apparent porosity of 29.61%, loss on ignition of 26.98%, and compressive strength of 7.08 MPa, satisfying standards for clay masonry units. Simultaneously, it enhances the thermal insulation by reducing thermal conductivity by 18% compared to the control sample with CMW. In this regard, the transition to a greener construction sector necessitates the immediate implementation of a circular economy approach to developing eco-friendly building materials by recovering large amounts of industrial waste, limiting the overuse of natural resources (e.g., clays), and improving the engineering properties of the final product. [ABSTRACT FROM AUTHOR]

The insatiable demand for lithium in portable energy storage necessitates a sustainable and low-carbon approach to its recovery. Conventional hydrometallurgical and pyrometallurgical methods heavily involve hazardous chemicals and significant CO2 emissions. Herein, by integrating electrode oxidation with electrolyte oxidation, we establish a photovoltaic-driven “dual-oxidation” seawater electrolyzer system for low-carbon footprint and high lithium recovery. A 98.96% lithium leaching rate with 99.60% product purity was demonstrated for lithium recovery from spent LiFePO4 cathode materials. In-depth mechanism studies reveal that the electric field-driven electrode oxidation and in situ generated oxidative electrolyte synergetically contributes to lithium ions leaching via a structural framework elements oxidation and particle corrosion splitting synergy. This dual-oxidation mechanism facilitates rapid and efficient lithium extraction with broad universality, offering significant economic and environmental benefits. Our work showcases a promising strategy for integrating dual oxidation within a photovoltaic-driven seawater electrolyzer, paving the way for low-carbon lithium recovery from diverse solid wastes and minerals within a sustainable circular economy. [ABSTRACT FROM AUTHOR]

Copyright of Low-Carbon Materials & Green Construction is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This review examines recent technological developments for recovering critical metals from mining and metallurgical waste streams, focusing on Co, Ga, Ge, In, Li, Ni, Re, Te, Sn, W, and V. Novel approaches using electrochemical methods, membranes, solvent extraction, and biomining are critically evaluated for their effectiveness and potential for industrial adoption. Key competitive advantages of these technologies are discussed, along with aspects requiring further research, such as process control, fouling issues, and microbial stability. The exploration of integrated and hybrid solutions combining different technologies is a potential game-changer for technology transfer. Finally, while these novel approaches show promise, further research is needed to overcome challenges related to cost, process control, and scalability. Addressing these issues is crucial for successfully transitioning these technologies from laboratory-scale experiments to industrial applications. By overcoming these hurdles, the mining and metallurgy sector can play a vital role in supplying critical metals for the zero-carbon transition while reducing its environmental impact and advancing toward a circular economy. [ABSTRACT FROM AUTHOR]

One of the challenges facing our current and future generations is the effective management of energy and its acquisition through more sustainable means. One solution is using materials capable of generating energy from temperature differences. Construction materials could be the answer, as they are already integrated into structures and have good thermoelectric properties. Geopolymers, emerge as a promising candidate due to their enhanced sustainability compared to alternative materials. Our research explored the use of geopolymers for electricity generation from heat. To minimize the usage of kaolin, we incorporated 50 % of two mining residues obtained from old mines located in Portugal. This approach optimizes the utilization of mineral resources and mitigates the environmental impact. Various methods were used to characterize this material, such as X-ray diffraction, simple compressive strength tests and evaluation of thermoelectric properties, such as the Seebeck coefficient and figure of merit. The geopolymers tested exhibit semiconductor characteristics, demonstrating poor heat conduction due to their low thermal conductivity. Regarding thermoelectric properties, these materials display N-type behavior, with a Seebeck Coefficient between −643 μV/°C and −2760 μV/°C. These findings underscore the advantages of utilizing this sustainable material for the widespread implementation of energy management in buildings on a large scale. [ABSTRACT FROM AUTHOR]

To achieve effective utilization of large-scale solid waste, this study prepared subgrade materials using mine waste, fly ash, and carbide slag as raw materials. The effects of the basic structure and composition ratio of the three raw materials on the performance of the subgrade materials were investigated. The mechanisms and strength enhancement effects of fly ash, carbide slag, and fly ash–carbide slag composite-stabilized mine solid waste were analyzed. The optimal mixing ratio of the subgrade materials was determined. When the mass ratio of carbide slag to fly ash was 1:4 and the total addition amount was 20%, the subgrade material had an optimal moisture content of 16.8%, maximum dry density of 1.70 g/cm3, and 90-day compressive strength of 8.51 MPa. This fully solid waste inorganic binder-stabilized subgrade material can effectively utilize large quantities of solid waste and meet the performance requirements of subgrade materials, thereby providing a good technical solution for large-scale solid waste disposal. [ABSTRACT FROM AUTHOR]

Mining in the Russian Far East has been developing for more than 100 years, resulting in the formation of mining technogenic systems that negatively affect all components of the environment. The purpose of this paper is to develop and present an ecological and geochemical model of supergene processes in tinsulfide and polymetallic ore mining systems. This paper presents, for the first time, the results of long-term field observations (more than 50 years): studies of numerous secondary minerals (more than 80) identified in mine workings and tailings, their natural associations, as well as the sequence, zonality, and stages of mineral formation as well as the characteristics of hydrochemical samples of river waters, contaminated by acid mine drainage (30 years of observations). Experimental modeling of sulfide oxidation was carried out under laboratory conditions (electrochemical method) and using Selektor software, which made it possible to study the process of acid mine drainage formation and to show the metal ions and ionic complexes composition, to establish Eh-pH parameters of crystallization for 52 secondary minerals, associations of primary and secondary minerals. The influence of water components on the formation of slurry and drainage in different time periods (dry, heavy rainfall, and snowmelt) is shown, and their mixing at the geochemical barrier "acid mine drainage—surface natural waters" is described. Experimental results are verified with numerous in-situ observations and mineralogical studies. The work allowed for the presentation of an environmental–geochemical model of ecosphere pollution, which describes not only the negative impact of sulfide-bearing systems of Russian Far East mining districts but locations all over the world. [ABSTRACT FROM AUTHOR]

The valorisation of sludges from aggregate production into construction materials is required for full circularity in mining waste management. This study explores valorisation pathways, relevant regulatory frameworks, and End-of-Waste (EoW) criteria for specific settings in Spain and Norway. The explored valorisation routes involved the production of filler, supplementary cementitious materials (SCMs), and lightweight aggregates (LWAs) for the production of cement-based products, and precursors for 3D printed construction material. The sludge from Norway revealed a non-polluted stream and a stream contaminated with organic phases and clays. Sludge-based filler proved suitable in concrete production with contents of up to 40% of total binder, providing adequate consistency and cohesion. However, clays in the sludge increased the demand for water and superplasticizer. Clay contents were still insufficient for the applications as SCMs, as the calcined sludge demonstrated limited reactivity. The application to produce LWAs was promising, but further microstructure optimization is still required. The clay content was also relevant for the sludge from the site in Spain, as it provided 3D printing mixes with good plasticity. The dosage optimization still required the addition of enzymes, limestone, and natural fibres to improve cohesion, workability, and resistance to the cracking of the 3D printing mix. [ABSTRACT FROM AUTHOR]

Plant growth on mine wastes is restricted by the lack of water, nutrients, phytotoxic responses and the absence of a seedbank. In a mesocosm study, we addressed the establishment of vegetation on metalliferous mine wastes from two seed mixtures. Besides the composition of the vegetation and the increase in plant cover and biomass over time, we studied concentrations of heavy metals in the shoot and analyzed the quantity of throughflow, its pH and EC to follow pollutant discharge. We hypothesized that the types of mine wastes and sown grasslands will affect species composition and the formation of a protective plant cover. Our platform was well-suited to study build-up and succession of a vegetation layer and its potential to stabilize mine wastes. However, the establishing community was less diverse than expected. The dilution of wastes increased species number and biomass, and we found a reduction of material discharge with increasing vegetation cover. Over time, drainage was reduced, while pH of the throughflow did not change. However, it was higher under the addition of greywater. Interestingly, the use of greywater led to a higher biomass in one mixture and slight changes in the chemistry of the throughflow and the plant matter. STATEMENT OF NOVELTY: Here, we present an integrative method to test the greening potentials of mine wastes. In the mesocosm approach different mine wastes, additives and seed mixtures can be screened and the potential of the establishing vegetation to reduce drainage and runoff may be addressed at the same time. Furthermore, analyses of pollutants in plants, soil substrates and drainage waters serve to study the phytoextraction and phytostabilization potentials of the established vegetation and their ecological services. [ABSTRACT FROM AUTHOR]

The production and consumption of coffee generates large amounts of waste which, if released into the environment, could cause unacceptable pollution. The search for alternatives for the use of these waste materials, namely coffee silver skin (CSS) and spent coffee grounds (SCG), is of great importance from an environmental and economic point of view. In this context, the present study was conducted to evaluate the use of CSS and SCG as mineral sources in order to strengthen their status as novel foods, which is currently not recognised. With the aim of validating the content of metals and metalloids in CSS and SCG, a comparative study of green and roasted coffee was also conducted. The results of the HR-ICP-MS analyses showed that coffee and coffee by-products contain high levels of macro essential elements: K (2387–35 993 mg/kg), Mg (1263–5298 mg/kg) and Na (82.6–170 mg/kg). Among the essential trace elements, Fe predominated with amounts between 41.8 and 728 mg/kg. The essential elements in the ultra-trace range (Mo, Cr, Co and Se) are found in amounts between 0.02 and 2.42 mg/kg. The content of toxic elements (Pb, As, Cd and Sn) is in the range of 0.01–0.25 mg/kg, which is below the maximum levels set by the EU Commission for these elements in foodstuff. However, the levels of Rb, Ba, Sr, Ti and Al are high, and range from 2.33 to 764 mg/kg. Considering the high content of essential elements in CSSs that are useful for daily human needs, the potential use of CSS should be encouraged. On the other hand, in order to meet the requirements for the use of novel foods, monitoring of potentially toxic elements must be carried out. [ABSTRACT FROM AUTHOR]

Currently, all the cement consumed in the Northwest Territories (NWT), Canada, is imported from other provinces (e.g. Alberta) by long-distance (∼1800 km) freight truck. Transporting cement over long distances not only raises its cost, but also results in a higher carbon footprint. Producing cement locally is therefore a potential low carbon and economic solution for the local industry. However, it is unknown if the local raw materials are suitable for cement manufacture, and there is a lack of a critical raw material – iron ore – for cement manufacturing. However, instead of iron ore, there are iron-rich tailings from a local rare earth element (REE) mine. Towards a low carbon and circular economy, the use of local raw materials (i.e. limestone, clay and gypsum) and mine waste (REE tailings) to manufacture cement in the NWT was explored and the first bag of cement in the history of the NWT was produced. Concrete samples made with the NWT cement achieved strength comparable to that of concrete based on commercial ordinary Portland cement. In addition, it was estimated that locally producing cement in the NWT has the potential to reduce carbon dioxide emissions by 3.0–61.7% as compared with importing cement from other provinces. [ABSTRACT FROM AUTHOR]

Hydraulic conductivity of conventional mock sodium bentonite (Na–B) and bentonite-polymer (B–P) geosynthetic clay liners (GCLs) were evaluated with three synthetic leachates that are chemically representative of aggressive leachates from coal combustion product (CCR) (I = 3179 mM), mining waste (MW) (I = 2127 mM, pH = 2.0), and municipal solid waste incineration ash landfill (MSWI) (I = 2590 mM). The mock B–P GCLs were created by dry mixing bentonite with branched, linear, or crosslinked polymer. The polymer loading of mock B–P GCLs ranged from 3 to 15%. Comparative tests were also conducted with Na–B GCLs. The mock Na–B GCLs cannot maintain low hydraulic conductivity to aggressive CCR, MW, and MSWI leachates. Mock B–P GCLs with 10% branched polymer had low hydraulic conductivity (< 1.0 × 10−10 m/s) to synthetic MW and MSWI leachates at 20 kPa effective confining stress, whereas the hydraulic conductivity of mock B–P GCLs with 10% linear or crosslinked polymer ranged from 1.5 × 10−9 to 1.4 × 10−7 m/s. As the effective stress increased, the B–P GCLs branched polymer showed a faster decreasing trend than that of Na–B and B–P GCLs with linear or crosslinked polymer. • Hydraulic conductivity tests were conducted up to 4 years to test long-term hydraulic conductivity of B-P GCLs. • The ratios of K L /K 6766 for B-P GCLs to synthetic CCP leachate were higher than that of Na-B GCLs (e.g., 3.5 to 14.7 vs. 1.7). • Polymer elution from B-P GCLs affects the long-term hydraulic conductivity of B-P GCLs. • The polymer elution should be measured and considered as an additional termination criterion in ASTM D6766. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: Gold mining wastes have long been a significant concern in Agusan del Sur, a gold mining district in the Philippines. The region is vulnerable to climate change effects such as typhoons and flooding, which may lead to contaminated runoff or overflow that could potentially harm the local agriculture and adjacent natural ecosystems. This study aims to analyze the properties of the gold mill tailings, investigate their potential for reutilization, and identify areas that need improvement in order to promote an inclusive approach towards the valorization of mine waste. METHODS: The samples were collected randomly from a small- scale gold mill tailings storage facility. The samples underwent analysis for elemental and oxide composition, particle dimensions, potential of hydrogen, lead, mercury, free cyanide and hexavalent chromium. A gap analysis was utilized to pinpoint the methods for enhancing a socially inclusive reuse strategy for the mill tailings. FINDINGS: The characterization of the tailings reveal that some heavy metals like zinc, titanium, copper, barium, and manganese, and hazardous substances like arsenic, mercury, and lead are present. Elevated levels of mercury, lead, and free cyanide were detected in the wastewater, with concentrations of 0.029 milligram per liter, 0.40 milligram per liter, and 1.9 milligram per liter, respectively, surpassing the allowable thresholds. There is a high risk of contaminating the neighboring ecosystem during flooding events and waste overflow. The tailings also contain fine particles of about 75 percent fine sand and 25 percent clay. Adequate maintenance of tailings storage facilities, community awareness of waste-related risks and hazards, legal frameworks and financial backing to encourage waste utilization, local community empowerment, and adherence to occupational health and safety guidelines in waste management are essential strategies to bridge existing disparities and foster a socially inclusive approach to mine waste valorization. CONCLUSION: The gold mill tailings contain hazardous substances and fine dust, potentially damaging the nearby ecosystem and community. It is essential to prioritize the maintenance of a well-managed tailings storage facility in order to avoid contamination. The reuse of gold mill waste tailings can bring about economic, social, and environmental advantages. However, there are gaps that must be addressed to achieve a socially inclusive gold mill waste circularization. The utmost importance should be placed on the health and safety aspect, and it is advisable to carry out a comprehensive investigation into the degree to which hazardous substances are polluting the surrounding ecosystem, including the local community. [ABSTRACT FROM AUTHOR]

Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Glass wool is an insulation material used in large quantities; despite its popularity, it is still surprising that around 2.5 million tons of mineral wool waste is generated every year in Europe. Waste management faces numerous challenges because, with current technologies, waste cannot be cleaned and melted again for repurposing, so even the recollected glass wool ends up in landfill. Herein, we present a hydrolysis technology that decomposes the binder applied to glass fibers using exclusively water. We succeeded in decomposing the resin from the surfaces of the end-of-life fibers, originating from different sources like industrial furnace insulation and two demolition-sourced building insulation wastes. The effects of temperature, pressure, the mass flow of the water, and the applied fluid ratio were investigated. The most important parameters are the temperature and the time for the decomposition, but to minimize glass loss through the solubility of glass, the fluid ratio plays an important role as well. The fibers were efficiently cleaned after only 20 min at 300 °C by the optimized parameters, with a mass recovery of 70 wt.%. [ABSTRACT FROM AUTHOR]

The SLS additive manufacturing industry enables the development of products for diverse applications with distinct properties due to its excellent surface finish and ability to create varied part geometries, but it consumes high-performance materials with high acquisition costs. An extensive quarrying of stone leads to the accumulation of mineral residues, posing environmental hazards by contaminating soil and water when disposed of in landfills. The primary objective of the study was to incorporate mineral waste into the SLS technique and investigate the influence of its addition, along with a silane-based chemical treatment, on the mechanical performance of polymer-mineral composites (PA12-slate). Additionally, the feasibility of producing a highly loaded printed prototype, employing 50 wt% of mineral waste, was examined. Samples of PA12, PA12 blended with 50 wt% slate waste, and slate waste treated with silane underwent fabrication via selective laser sintering (SLS) and subsequent mechanical characterization, including tensile, flexural, and compressive tests. Additionally, the samples underwent accelerated aging using a QUV weathering tester, followed by mechanical characterization. The geometric accuracy, stability, and processing feasibility of these formulations were evaluated through SLS-printed composite prototypes utilizing PA12_50Sla_Si. It was found that the addition of 50% of slate to the PA12 presented mechanical properties decreasing compared to the printed PA12 only. However, an increase was verified when using silane-induced mineral bonding. The incorporation of mineral agents and silane enhanced the resistance of PA12 to aging. However, after aging, both tensile and flexural strength decreased across all printed samples. Nonetheless, this study showcased the feasibility of producing complex PA12-slate waste specimens containing up to 50 wt% of mineral waste using the SLS printing technique. Therefore, SLS presents itself as a viable means of adding value to this mineral waste. [ABSTRACT FROM AUTHOR]

We developed a spatiotemporal mapping approach utilizing multiple techniques for distinguishing and mapping known reclaimed mine sites from "unreclaimed" mine sites in a historic uranium mining district along the South Texas Coastal Plains. Lidar laser scanning penetrates the vegetation canopy to expose anthropogenic modifications to the landscape. The Lidar analysis (bare earth elevation surface, slope, topographic contours, topographic textures, and overland-flow hydrography) revealed mine features. Visual interpretation of Landsat imagery and time-series analysis augmented the Lidar analysis revealing the temporal life cycle of mining. The combination of bare earth texture with time-lapse and time-series analyses revealed areas of disturbance for reclaimed mines. The spatiotemporal mapping approach proved to be most useful in identifying and characterizing the known mine pit and pile features, reclamation status, and areas of disturbance due to mining. Two mine waste volume estimation methods resulted in a 21% difference indicating that although the approach helps to map mine features and areas of mining disturbance for the purposes of mine land inventory, additional information is needed to improve the estimation of buried mine waste at reclaimed mine sites. [ABSTRACT FROM AUTHOR]

[Display omitted] • High concentrations of pollutants were present in runoff flowing through tailings. • Metals have strong migration ability in TCLP environment. • The cumulative release of Mn, Zn, Co, and Ni was larger. • Seepage affects the chemical fraction of metals in tailings. • Mn has posed a serious threat to groundwater. The continued growth in demand for mineral resources has led to a large amount of mining wastes, which is a major challenge in the context of carbon neutrality and climate change. In this study, runoff migration, batch leaching, and column experiments were used to investigate the short-, medium-, and long-term leaching of heavy metals from legacy tailings, respectively; the cumulative metal release kinetic equations were established, and the long-term effects of tailings leaching were verified by HYDRUS-1D. In runoff migration experiments, surface dissolution of tailings and the co-migration of adsorbed soil particles by erosion were the main carriers in the early stages of leachate formation (Mn ∼ 65 mg/L and SO 4 2- up to 2697.2 mg/L). Batch leaching tests showed that the concentration of heavy metals in soil leached by acid rain were 0.1 ∼ 22.0 μg/L for Cr, 0.7 ∼ 26.0 μg/L for Cu, 4.8 ∼ 5646.0 μg/L for Mn, 0.3 ∼ 232.4 μg/L for Ni, and 1.3 ∼ 448.0 μg/L for Zn. The results of column experiments indicated that some soluble components and metals with high mobility showed a significant decreasing trend at cumulative L/S ≤ 2. Additionally, the metals have higher leaching rates under TCLP conditions, as shown by Mn > Co > Zn > Cd > Ni > Cu > Pb > Cr. The fitting results of Langmuir equation were closer to the cumulative release of metals in the real case, and the release amounts of Mn, Zn, Co, and Ni were higher with 55, 5.84, 2.66, and 2.51 mg/kg, respectively. The water flow within tailings affects the spatial distribution of metals, which mainly exist in relatively stable chemical fractions (F3 + F4 + F5 > 90 %) after leaching. Numerical simulation verified that Mn in leachate has reached 8 mg/L at a scale of up to 100 years. The research results are expected to provide technical basis for realizing the resource utilization of tailings in the future. [ABSTRACT FROM AUTHOR]

Metal sulfide oxidation in abandoned exposed stone coal mines leads to the generation of Acid Mine Drainage (AMD), characterized with high uranium concentration, which is a major concern for local public health. This work employed approaches of geochemical analysis and modeling to determined the mode of occurrence of uranium. Additionally, potential environmental risks were evaluated. The results revealed that the primary source of uranium pollutants in the surrounding environmental media was attributed to the weathering of mine wastes. The acidity and concentrations of harmful metals (e.g., U, Fe) and sulfate in water rapidly decreased to background level with increasing distance from the mine. The geochemical distribution characteristics of sediments and water exhibited notable similarities. The species of uranium underwent a transformation as uranium in mine waste rocks migrated to environmental media. In acidic pit water, uranium primarily existed as uranyl sulfate, gradually transitioning downstream to complexes dominated by hydrophosphate and carbonate. This transition was accompanied by the coprecipitation of significant amounts of uranium with phosphate and iron hydroxides. Results from the geoaccumulation index (Igeo) and risk assessment codes (RAC) indicated that uranium in unweathered waste rocks and newly formed pit sediments posed a high environmental risk, with a bioavailable fraction reaching up to 26.44% and 48.0%, respectively. This research holds significant importance in devising remediation and management strategies for abandoned coal mines to mitigate the impact of uranium release and mobility on the surrounding ecological environment. Highlights: The weathering of stone coal waste is the main source of uranium pollution. Newly formed pit poses strong acid generation capacity and high environmental risk. The mode of occurrence and environmental conditions determine the mobility of uranium. [ABSTRACT FROM AUTHOR]

Stockpiles containing sulfide minerals are subject to oxidation reactions when exposed to atmospheric conditions, which can result in the formation of acid mine drainage (AMD). Reactive waste rock has limited re-use potential due to the contamination risk associated with the generated drainage water. The re-use of reactive waste rock could lead to a significant reduction in the volume of waste rock as it mitigates the environmental impact of mine waste deposition. Acid mine drainage generation rate depends on sulfide weathering kinetics which are controlled by many parameters such as the mineralogy and the particle size. Fine fractions of waste rock have higher specific surface areas and degree of liberation of sulfides, resulting in greater reactivity than the coarse fractions. The objective of this research was therefore to evaluate the potential of re-use by controlling particle size using the sieving method. Two different potentially acid-generating waste rocks were divided into six fractions and subjected to both static and kinetic tests. Prediction of the geochemical behavior using static test did not consider the liberation of the minerals, and the long-term prediction was therefore overestimated. Results of the kinetic columns showed there was less oxidation of the sulfide minerals in the coarse fractions than in the fine fractions. Additionally, the distribution of sulfidic minerals and neutralizing minerals with particle size is influencing the potential of the re-use of the reactive waste rock. [ABSTRACT FROM AUTHOR]

There are about 3159 open dump sites in India, which cause severe environmental pollution and are a danger to public health. This study demonstrates that the embedded resources in these dumpsites can be recovered profitably. The paper surveys the excavation, segregation, re-cycling and re-use of an open dumpsite containing legacy waste, at a cost of 8 $/m3 of rubbish, recovered, incinerable and inert fractions. A land reclamation of 3.16 ha yielding 1048 tonnes of refuse-derived fuel was achieved. This study demonstrates that dumpsite mining can be profitable while preventing the environmental hazards caused by existing waste dump sites in most Indian cities. [ABSTRACT FROM AUTHOR]

Brazilian mining ventures aged 30 years or older were studied, revealing historical oversights in environmental planning that have caused substantial environmental liabilities during active mining and decommissioning. Electrical resistivity tomography surveys were conducted in a decommissioning uranium mine in southeast Brazil. The results provided valuable insights into local hydrogeological dynamics, revealing the flow of acid mine drainage in two distinct systems: the porous waste rock pile and the fractured underlying crystalline basement. Geo-electrical sections displayed conductive anomalies indicating hydraulic connectivity between the waste rock pile and the underlying fractured aquifer through crystalline basement fractures. This connection was substantiated by sub-vertical zones of low electrical resistivity interpreted as groundwater influx from the porous system to the fractured aquifer. Consequently, the waste rock pile acted as a localized recharge zone for the regional aquifer, facilitating chemical exchanges between the two systems. Furthermore, the study successfully differentiated less impacted saturated zones (resistivity ≈80 Ω·m) from those associated with acid mine drainage (< 40 Ω·m). Preliminary investigations identified a complex fracture network in the study area, comprising two main fault systems with preferential NE and NW orientations, nearly orthogonal to each other. This fracture network demonstrated continuity, playing a fundamental role in sustaining flow within the local and regional drainage network. [ABSTRACT FROM AUTHOR]

Lanthanum (La(III)) is one of the high-demand rare earth elements with applications in various products. However, La(III) in mining waste streams and electronic waste also poses environmental and health concerns. Therefore, the recovery of La(III) in the waste is needed. In the present study, the adsorption of La(III) with Dowex 50W-X8, Amberchrom50WX4, Amberlyst 15, and Amberchrom 50WX2 was evaluated using a shaker water bath. Dowex 50W-X8 was found to be the best adsorbent and was used to investigate the effect of the shaker speed (RPM = 50–150), adsorbent dosage (1.0–4.0 g), pH (2.0–7.0), and temperature (20–40 °C) on adsorption. La(III) adsorption was found to increase with the shaker speed, as expected. On the other hand, the adsorption capacity decreased with the adsorbent amount. Also, the highest La(III) adsorption was observed at pH = 6.0. La(III) percentage removal did not vary significantly with a temperature from 20 °C to 40 °C. However, the first-order kinetic rate constant decreased moderately with increases in temperature. The adsorption of La(III) by Dowex 50-X8 followed the Freundlich isotherm model better than the Langmuir model. In addition, the adsorption kinetics were represented well by the pseudo-first-order kinetic model. Moreover, enthalpy and Gibbs free energy changes were found to be negative, indicating an exothermic and thermodynamically favorable adsorption process. [ABSTRACT FROM AUTHOR]

The increased exploitation of ores leads to the generation of mining waste, which has a negative impact on the environment and human health. For this reason, it is necessary to take care of it in an adequate way by applying some of the possible treatments. In addition to protecting the environment by applying appropriate treatment, there is also the possibility of making a profit by valorizing useful elements from mining waste. In order to choose the most adequate treatment, it is necessary to perform the characterization of mining waste. This paper contains a detailed characterization of the flotation tailings deposited at the Old Flotation Tailings in eastern Serbia, originating from copper ore processing. Characterization includes physico-chemical analysis, polarizing microscope analysis, X-ray Diffraction analysis (XRD) and Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) analysis analysis. The obtained results indicate that the investigated flotation tailings can be used as a secondary raw material for metal recovery, in this case primarily copper (whose content is about 0.24%), gold (with a content of about 0.43 ppm) and silver (with a content of about 1.7 ppm). Considering that the content of valuable elements is quite low, it is suggested to apply hydrometallurgical treatment for their recovery. [ABSTRACT FROM AUTHOR]

The strength of rockfills and waste materials is significantly influenced by their particle size distribution (PSD). For large waste rockfills, PSD is fundamental to determine the shear behavior. Traditionally, PSD for rockfill, used in materials like coarse-grained aggregates, has been obtained through physical sieving. However, the particle sizes in hard rockfills can vary significantly from small particles (< 20 cm diameter) to large blocks or boulders over 100 cm, with the maximum size limited by the in situ ground conditions and blasting performance. Essentially, the sieving process is impractical, considering the scale of the mine waste dumps and the time required. Therefore, in this study, a workflow using digital detection to estimate the PSD is presented, aiming to quantify the waste dump shear strength using Barton–Kjaernsli empirical criterion. PSD from UAV is validated using manual field measurements of individual boulders. The error for coarse characteristic size prediction ranges within ± 4 mm, and the increase in the data collection frequency, area covered, and resolution of fragmentation measurement for rockfills and waste dumps using UAV allows to improve the statistical reliability of the PSD and fragmentation measurement. [ABSTRACT FROM AUTHOR]

There is a general consensus that bio-waste is a suitable material for valorization by means of the fermentation process with the production of biogas. The success of a bio-waste closed-loop economy will ultimately be determined by the demand for the products made from it. Poor-quality composts and fermentation products will not be allowed on the market in the long term. This means that not only final products but also bio-waste from separate collections must also meet the quality requirements. The aim of this 12-month study was a monthly analysis determining the level of contaminants in bio-waste collected from rural communities, single-family neighborhoods in urban areas, and multi-family neighborhoods in urban areas. The share of contaminants in bio-waste from rural areas and single-family urban housing averaged 8.2% and 7.2%, respectively, while multi-family urban housing had a significantly higher average of 16.6%. The primary contaminants identified were treated wood, plastics, mineral wastes, paper, and glass in rural areas and plastics, paper, treated wood, glass, and textiles in urban areas. The close positive correlation found between the total content of pollutants and, in particular, with plastics and kitchen waste in bio-waste collected in rural communities and from multi-family housing in cities indicates that they are likely the main source of the origin of these pollutants. [ABSTRACT FROM AUTHOR]

The construction sector is presently among the most resource-intensive industries, driving a substantial body of research dedicated to the development of more sustainable materials to address these demands. A particularly promising approach within the framework of the circular economy is the repurposing of waste as a principal raw material for the creation of new construction products. Within this context, the primary aim of this study is to engineer ceramic materials for brick production using 100% waste-derived inputs, specifically aggregate washing sludge and manganese mining by-products. To evaluate the potential of these sustainable ceramic materials, an extensive investigation was conducted, encompassing both physical and mechanical testing, as well as a thorough characterisation of the waste inputs. For this purpose, a series of ceramic specimens were fabricated with varying proportions of mining residues and aggregate washing sludge, adhering to the conventional protocols employed in the manufacture of ceramic bricks. The results demonstrate that these sustainable ceramics exhibit a linear shrinkage reduction of up to 5% compared to traditional clay-based ceramics. Furthermore, they show water absorption levels—whether via capillarity, cold water, or hot water absorption—that are up to twice those observed in conventional clay ceramics, while maintaining comparable density values. This increased absorption, however, correlates with a reduction in mechanical strength at higher concentrations of manganese waste, yet the material continues to meet the minimum strength requirements as specified by industry standards for such products. In conclusion, this research introduces a novel, sustainable ceramic material that not only reduces economic and environmental costs but also adheres to the required performance criteria for construction applications. [ABSTRACT FROM AUTHOR]

This account presents information on all aspects of the biology of Silene uniflora Roth (S. maritima With., S. vulgaris Garcke subsp. maritima (With.) Á. & D. Löve), Sea Campion, that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of Britain and Ireland: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history and conservation.Silene uniflora is a mat‐like perennial herb that in Britain and Ireland is primarily distributed in coastal habitats, notably on sea cliffs and shingle banks but also at the drift line and rarely on sand; it also has populations on mountains and heavy metal mine waste tips. All of these substrates tend to be oligotrophic, loose‐textured and freely draining, and often with adverse ion concentrations. It is found in suitable habitats around much of the Atlantic and Baltic coasts of Europe.Its breeding system is gynodioecious and gynomonoecious (some individuals bearing female flowers only, some bearing hermaphrodite flowers only and others with both types of flower). The proportions of the three types of individual vary considerably between populations, but hermaphrodite flowers tend to predominate. The showy, white, nectar‐producing flowers are produced continuously over the entire summer and are pollinated mainly by long‐tongued Hymenoptera and night‐flying moths but autogamous selfing is also frequent.Silene uniflora and its close relative S. vulgaris were the subject of a classic, decadal study involving genetical and transplant experiments that was seminal in the development of 'experimental taxonomy'. More recently, attention has focused on the rapid evolution of Zn‐tolerant populations of S. uniflora growing on mine spoil and contaminated river gravels. It has also become a model organism for the study of sexually transmitted, castrating fungal diseases in plants (notably of the genus Microbotryum). [ABSTRACT FROM AUTHOR]

Metals and metalloids are persistent contaminants that are associated with many anthropogenic activities and mining in particular. On August 6, 2014, approximately 40,000 m3 of toxic acid mining waste was spilled from the Buena Vista del Cobre Copper Mine. The spill affected 220 km of the Sonora River Basin (SRB) over a surface area of ~ 30,000 km2. This study evaluated the total and bioaccessible concentrations of six metals and their enrichment in surficial sediments in spill and no-spill sites in the SRB. All metal concentrations showed significant seasonal and spatial variation (p <.05) in surficial sediments, with a general distribution of Al > Fe > Mn > Zn > Cu > Pb. The total and bioaccessible concentrations of the elements in this study were similar between spill and no-spill sites. Variations in element levels were associated with re-suspension and advection related with rain run-off, and the element concentrations were associated with the high natural concentrations in surficial sediments found throughout the SRB (considering the predominant soil types). The enrichment factor (EF) indicated minor to moderate-severe enrichment of Fe and Mn, minor to severe enrichment of Pb and Zn, and moderate-severe to very severe enrichment of Cu. The bioaccessible percentages of metals with respect to the total concentrations varied from 0.23 to 69.9%. The Sediment Quality Guidelines criteria indicated that adverse effects on biota that are mainly due to Cu levels are potentially present. Chronic exposure to metals may produce intermediate and long-term effects on the metabolic responses of biota. [ABSTRACT FROM AUTHOR]

The growing mining industry has led to environmental pollution, primarily from mining waste known as acid mine drainage (AMD). To effectively address AMD, a combination of constructed wetland and biochar treatment is necessary. This study aims to assess the ability of biochar in combination with wetland sediment to reduce sulfate and cadmium (Cd) heavy metals in AMD. The research method involved a laboratory-scale constructed wetland in a microcosmos and a treatment of: T1, biochar mixed with wetland sediment; T2, sediment; T3, biochar; and T4, control with no treatment. Observations included sulfate content, pH determination, heavy metal concentration, and scanning electron microscope (SEM) analysis of the biochar. Results after 30 days of observation showed that T1 reduced sulfate concentration by 72.03%, compared to 63.33% for T2, 63.33% for T3, and 2.50% for T4. The reduction in sulfate was accompanied by a consecutive increase in pH, with T1 at pH 6.9, T2 at pH 6.6, T3 at pH 6.4, and T4 at pH 3.6 after 30 days. T1 treatment reduced heavy metal Cd by 80.16% after 30 days, while T2 of 55.46%. T3 of 65.83% and T4 of 2.31%. This indicates that the constructed wetland method, combined with biochar, is more effective in reducing sulfate and the heavy metal Cd in AMD, compared to using only biochar or wetland sediment treatment. [ABSTRACT FROM AUTHOR]

This paper presents the construction of a numerical three-dimensional model of the area of the Żelazny Most Mining Waste Storage Facility (MWSF). In the study area, the difficult geological conditions associated with glaciotectonics are accompanied by a complex hydrotechnical system of sediment deposition and sedimentary water drainage. In order to effectively reflect the water flow paths, a detailed schematization was carried out, using 700,000 boreholes and more than 300 hydrogeological cross-sections. In addition, numerous drainage sections, streams, and ditches were included to reliably assess the amount of saline water entering the underlying aquifers. This research was supported by magnetic resonance sounding (MRS) studies of the reservoir's sediments. The MWSF is currently being expanded, so the work primarily focuses on illustrating changes in the hydrodynamic field resulting from the inclusion of the new southern section. Models of similar facilities have been implemented before, but in the current one, the combination of meticulous analysis of the hydro-structural system, the water balance, a significant amount of data, the size of the facility, and the use of an unstructured discretization grid in the calculations is undoubtedly innovative and will be an important contribution to the development of analogous solutions around the world. [ABSTRACT FROM AUTHOR]

Copyright of China Mining Magazine is the property of China Mining Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mineral wool is commonly used in construction as thermal insulation material. After the product's lifetime, it is classified as hazardous waste if no trademark of the European Certification Board for Mineral Wool Products (EUCEB) or the German Institute for Quality Assurance and Labelling (RAL) exists. Mineral Wool Waste (MWW) is typically landfilled in Europe, which is challenging due to its low bulk density and dimensional stability. This circumstance highlights the need for alternative recycling methods that increase the recycling rate of construction and demolition (C&D) waste. This article outlines the recycling opportunities of MWW and focuses on the use of thermochemical treatment of different mixtures of input materials to produce a supplementary cementitious material (SCM). The material characterisation results and investigations on the binder suitability demonstrate that the slag fractions after the thermochemical treatment are well-qualified to be used as reactive binder components. Additionally, a material flow analysis was conducted to estimate the substitution potential of MWW as SCM in the Austrian cement industry. [ABSTRACT FROM AUTHOR]

Both the mineralogy and geochemistry of coal mine waste presents environmental and social challenges while simultaneously offering the potential source for recovery of metals, including critical raw materials (CRMs). Assessing these challenges and opportunities requires effective waste management strategies and comprehensive material characterization. This study deals with the integration of analytical data obtained from various portable sensor technologies. Infrared reflection spectroscopy (covering a wide wavelength range of 0.4 to 15 µm), and geochemical x-ray fluorescence (XRF) were utilized to differentiate between samples belonging to various geological lithologies and quantify elements of interest. Therefore, we developed a methodological framework that encompasses data integration and machine learning techniques. The model developed using the infrared data predicts the Sr concentration with a model accuracy of R2 = 0.77 for the testing dataset; however, the model performances decreased for predicting other elements such as Pb, Zn, Y, and Th. Despite these limitations, the approach demonstrates better performance in discriminating materials based on both mineralogical and geochemical compositions. Overall, the developed methodology, enables rapid and in-situ determination of coal mine waste composition, providing insights into waste composition that are directly linked to potential environmental impact, and the possible recovery of economically valuable metals. [ABSTRACT FROM AUTHOR]

Groundwater quality can be impacted by the backfilling of coal pits with waste rock containing new mineral surfaces and nanomaterials. This study was implemented to identify newly available arsenic and selenium sources in waste rock from the Cordero Rojo Mine in the Powder River Basin, Wyoming, to highlight the alteration of contaminant sources with the transition from an overburden geologic state to the mined waste rock. Basic kinetic models were constructed to replicate the possible weathering modeling scenario derived from published sources of arsenic and selenium in the Powder River Basin overburden—pyrite and gypsum, respectively. These basic prediction models were unable to capture the arsenic and selenium trends recorded for a saturated column loaded with waste rock from the Cordero Rojo Mine. Enhanced kinetic models were tested through trial and error to capture newly available sources created by the mining of the waste rock. The incorporation of new source contributions produced modeled arsenic and selenium trends similar to the observed trends in water extracted from the column. The identification of newly available contaminant sources in backfill waste rock is necessary to evaluate the potential release of contaminants and the exceedance of water quality criteria for overburden formations that have not previously shown the potential for water quality contamination. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the toxic potential of mining residues by 1) evaluating the concentrations of heavy metals and arsenic in soil and earthworm's samples from impacted and reference sites in Charcas and Villa de la Paz, San Luis Potosí, México; and 2) evaluating effects by laboratory bioassays and the comet assay in the earthworm Eisenia andrei. Methods: The quantification of metals in soils was carried out by the Thermo Scientific Niton XL3t Gold Serie 500 environmental analyzer for X-ray fluorescence (XRF), and in the earthworm tissue through ICP-MS. The evaluation of the genotoxic potential of soils was assessed through movility and exposure bioassays with earthworms, determining DNA damage using the comet assay at the end of the bioassays. Results: In Charcas, the concentrations in soils of heavy metals from highest to lowest were: Pb > Cu > Mn > Cd (Impacted); and Mn > Pb (Reference). In Villa de la Paz, the concentrations were: As > Mn > Cu > Pb (Impacted) and Mn > Pb > As (Reference). The exposure pattern to heavy metals in earthworms in Charcas was: Pb > As (Impacted and Reference); and in Villa de la Paz it was: As > Mn > Pb > Cu > Cd (Impacted), y Pb > As (Reference). In both mining districts, the magnitude of DNA damage in earthworms was: Impacted > Reference > Control. Conclusion: The results indicate that the impacted soils of both sites represent a significant source of exposure to edaphic organisms, with a notable genotoxic potential. [ABSTRACT FROM AUTHOR]

Natural resource depletion and increased mining waste pose significant challenges to global sustainability efforts. This study investigates the processability of mining waste during the metal recovery stage to evaluate its potential contribution to anthropogenic circularity. The mining industry, abundant in valuable metals that are crucial for a carbon-neutral economy, plays a pivotal role in this context. We determine the grades of metals by looking at their chemical makeup, and then we use statistical entropy to model how easy it is to process certain waste materials. This provides us with processability measures that range from 0.19 bit to 1.18 bit. Our findings highlight that while some waste contains "abundant" metals, its complexity may diminish its economic value, raising concerns about its environmental impacts and resource availability at the end-of-life stages. Estimating potential revenue involves multiplying processed amounts by commodity prices, revealing a maximum value of 8.73 USD/metric ton for processed waste. This assessment underscores the importance of integrating circular economy principles, aiming to mitigate environmental damage and promote industrial ecology. By advancing our understanding of mining waste management through rigorous scientific inquiry, this study contributes to sustainable resource utilization strategies that are essential for future industrial practices and environmental stewardship. [ABSTRACT FROM AUTHOR]

Phosphate mining generates substantial quantities of waste rock during the extraction of sedimentary ores, leading to significant environmental concerns as these wastes accumulate around mining sites. The industry is under increasing pressure to adopt more sustainable practices, necessitating considerable financial investments in remediation and technological advancements. Addressing these challenges requires a holistic strategy that balances social responsibility, environmental preservation, and economic viability. This study proposes an innovative, cost-effective, and environmentally friendly method to manufacture compressed stabilized earth bricks by combining the valorization of phosphate waste rock (PWR) and phosphate washing sludge (PWS). These bricks offer numerous advantages, including low embodied energy, robust mechanical performance, and excellent insulation and thermal properties. Initially, a Toxicity Characteristic Leaching Procedure (TCLP) test and radiometric surface contamination measurement, carried out on raw materials (PWR and PWS), showed that the results were below the permissible limits. Then, the chemical, mineralogical, and geotechnical properties of the raw materials were characterized. Subsequently, various mixtures were formulated in the laboratory using PWR and PWS, with and without cement as a stabilizer. Optimal formulations were identified and scaled up for pilot production of solid bricks with dimensions of 250 × 125 × 75 mm3. The resulting bricks exhibited thermal conductivity and water absorption coefficients that satisfied standard requirements. This method not only addresses the environmental issues associated with phosphate mining waste but also provides a sustainable solution for building materials production. [ABSTRACT FROM AUTHOR]

The snow/pink crab (Chionoecetes opilio) and Northern shrimp (Pandalus borealis) are widely distributed in the North Atlantic Ocean. During processing/consumption, about 80% of the harvest is discarded as processing waste, which is a rich source of protein, chitin, minerals, and carotenoids. This study, for the first time, investigated the proximate composition and individual amino acids, minerals, and carotenoids from different body parts (carapace, shoulder, claw, tip, and leg) of snow crabs and shrimp shells. Shrimp proteins were found to be abundant and well-balanced in their amino acid composition. Compared to shrimp shells, a lower content of amino acids was found in the snow crab, depending on the part of the shell used. Moreover, crab shells, mainly crab claws, contained a higher (p < 0.05) level of chitin compared to shrimp shells. Seven micro-elements (Mn, Fe, Cu, Zn, As, Ba, and Ce) and six macro-elements (Ca, Na, K, Mg, P, and Sr) were identified using inductively coupled plasma-mass spectrometry (ICP-MS). Among them, calcium and iron were higher in crab carapaces (p < 0.05), followed by shrimp shells and other crab shell segments. Additionally, shrimp and crab carapaces contained a significant level of carotenoids, and these were mainly composed of astaxanthin and its mono- and diesters, along with zeaxanthin, astacene, canthaxanthin, and lutein. Thus, this investigation provides detailed information to allow upcycling of shellfish waste and addresses the knowledge gap concerning the availability of various nutrients in different crab sections and shrimp shells. [ABSTRACT FROM AUTHOR]

Purpose:In order to reduce the storage of mine solid waste, reduce the disposal cost and improve the recovery rate of underground ore, aiming at the problems of low concentration, difficult flocculation and sedimentation, overflow and mixing in the filling of mine fine filter mud, taking a lead-silver mine in Henan as an example,a precise preparation and filling system process for the co-disposal of filter mud and rice stone was proposed. Method;The basic physical properties,fluidity and strength tests of filter mud and rice stone were carried out. Through theoretical analysis and research, combined with the actual situation on site, the multi-material collaborative cementing filling process of the lead-silver mine was proposed,and the construction and industrial test of the filling system as carried out. Result;l)The particle size of filter mud less than 74 im accounted for 94%. When the ratio of filter mud to rice stone was 5 : 5, the content of filling aggregate below --20 pjn accounted for more than 20%, which could meet the long-distance transportation of filling slurry. 2) The static metering cycle preparation process was adopted. The filter mud was measured by the viscous batching machine,and the rice stone was measured by the conventional batching machine, which could realize the homogeneous dispersion and precise feeding of the viscous filter mud,and ensure the stable and continuous operation of the filling system. 3)In the field industrial test, the filling concentration was 64%, the homogenization degree of the filling slurry was high, the filling system ran [ABSTRACT FROM AUTHOR]

Superfine tailings-blast furnace slag backfill (SBB) has been designed for recycling solid waste in mines and decreasing the cost of the overall process. During the mining process, the decrease of adjacent ore rock causes backfills water loss and its exposure to air. The mechanical behavior of SBB was investigated by uniaxial compressive strength (UCS), acoustic emission (AE) characteristics, and numerical simulations. Wavelet transform and fast Fourier transform were used to obtain the frequency components of AE events during the whole loading. The results indicated that the main frequency components of AE signals in SBB were close to 100 kHz, while medium and high-frequency components could be also distinguished for specific specimens with certain water loss. Particle flow code (PFC), a typical discrete element method (DEM), could reproduce the stress–strain curves of SBB specimens with varied water loss and simulate AE events of SBB during the loading. For the whole loading process, both indoor experiments and numerical simulation showed that AE events and simulated AE clusters began in the early stage of loading, which indicated that the crack initiated from a low stress level. [ABSTRACT FROM AUTHOR]