Grinding is an essential process in mineral processing. Hydrogen-based mineral phase transformation, used to efficiently process refractory iron ores, can alter the physical and chemical properties of the ore, affecting its grinding characteristics. This paper uses iron ore from Baoshan, Shanxi Province, as the raw material for laboratory-scale hydrogen-based mineral phase transformation (HMPT) experiments and grinding tests. It examines the impact of four cooling methods on the ore’s grinding characteristics. The results show that samples cooled in a reducing atmosphere to 200 °C and then water-quenched exhibit the best relative grindability. For the same grinding time, the content of coarse-sized particles (+0.074 mm) in the product is lowest, while the fine-sized particles (−0.030 mm) is highest. The grinding kinetic parameters of the samples with this cooling method are the highest. After 2 min of grinding, the value of n is 1.3363, and the particle size distribution of the product is the most uniform. The BET and SEM test results indicate that samples with this cooling method have more internal pores, the largest pore size, and the most surface cracks and pores. This paper clarifies the effects of the HMPT cooling methods on grinding characteristics, providing a theoretical foundation for the efficient separation of iron ores.

Sedimentary systems affected by high fluxes of reactive iron develop a so-called ‘cryptic’ sulfur cycle in which hydrogen sulfide is nearly fully reoxidized and its concentrations of hydrogen sulfide in the porewaters are in the submicromolar range. The sediments of the Gulf of Aqaba represent a classic example of such a system. The goal of this work was to provide quantitative constraints on hydrogen sulfide concentrations in the sediments of the Gulf of Aqaba. Sulfate reduction rates in the sediments of the Gulf of Aqaba were found to be lower than in marine sediments that had not been affected by high fluxes of the reactive iron, while the rate constants of hydrogen sulfide oxidation were found to be higher than in the highly reactive iron-rich sediments of the Svalbard fjord. A combination of slow rates of sulfate reduction and fast rates of hydrogen sulfide oxidation results in concentrations of hydrogen sulfide in the porewater, both measured and calculated, that are below 100 nmol l −1 . We suggest that a similar cycling of sulfur species may occur in organic-matter-poor marine systems situated in dry environments with highly reactive iron mineral delivery, such as the Red Sea and the Atlantic Ocean in the vicinity of the Sahara.

The currently available hot briquetted iron (HBI) typically contains approximately 1 wt.% carbon. In the CO-CO2 atmosphere of a blast furnace, carbon loss from iron is significant, accompanied by overoxidation. Based on the high metallicity of HBI, this study designed iron particles with varying carbon contents. These pellets were mixed with three typical blast furnace iron ores-sinter, pellet, and lump- and subjected to thermogravimetric analysis reduction experiments. The investigation explored the effects of substituting 15 wt.% sinter with HBI containing different carbon contents and assessed the resulting impact on the temperature difference between iron and slag melting, ultimately determining the optimal carbon content for blast furnace operations. The findings showed that the addition of iron particles with carbon contents exceeding 1.6 wt.% achieved reduction rates and iron-slag melting characteristics similar to those of typical blast furnace charges. When iron particles containing 3.6 wt.% carbon were added, the iron oxides of various valence states in the charge and pellets exhibited the highest availability of carbon for both direct and indirect reduction. Consequently, the slag melting temperature rose to 1398 °C. Due to the presence of unreacted carbon, the molten iron melted at approximately 1530 °C, while the iron-slag dripping temperature range narrowed to 132 °C, achieving the optimal temperature range for blast furnace application.

Open dumping and disposal of waste iron ore in freshwaterand landfillsare increasing environmental concerns. Therefore, following the environmentalsustainability and circular economy approach, this study recoverediron-based coagulants from waste laterite ore (WLO) and assessed theirperformance in water treatment. Chemical leaching of WLO was performedusing HCl with varying acid concentrations, temperatures, and treatmenttimes. The optimum iron solubilization efficiency of 86% was achievedat an optimized HCl concentration of 13 mol/L, a reaction temperatureof 90 °C, a mixing speed of 500 rpm, and a treatment time of240 min. The recovered WLO-based iron coagulant exhibited a greenishcolor and showed promising performance in treating water from theRiver Indus Canal, particularly in removing turbidity and heavy metals.This performance of the WLO-based iron coagulant was nearly identicalto that of conventional ferric chloride. Overall, recovering iron-basedcoagulants from WLO may reduce the cost of coagulating drinking wateror wastewater. Furthermore, the present study’s findings willbe useful in protecting the environment by either not dischargingthe WLO into freshwater bodies or by dry stacking.

The study aimed to examine the thermophysical properties of briquettes as an alternative to indurated iron ore pellets in the formation of an artificial bottom bed in horizontal-grate machines. The methodology included physical simulation of the drying process (circulation of a heat transfer agent at 150/300℃), dilatometric analysis, measurement of temperature profiles in briquettes, and mathematical modeling with the use of TOREX Sensible Indurating Machine software. The briquettes were made from oxidized ferruginous quartzite concentrate with organic and inorganic binders (cement; bentonite) under a load of 15 t (cylinders measuring Ø35×35 mm). It was established that excessive moisture during drying does not reduce the strength of briquettes (70.1 daN/briquette) due to their low porosity (10% as compared to 30% in pellets) that limits water absorption. The drying of briquettes was shown to proceed 30–40% slower due to their reduced specific surface area and permeability compared to iron ore pellets, thus requiring adjustments to the heating conditions. The thermal conductivity coefficient amounted to 0.12 W/(m·K). During firing, sintering occurs exclusively in the surface layers (depth of 2–3 mm) since the inner zones do not reach the sintering temperature threshold (>1000℃) due to the low thermal conductivity of the material. The integrity of the briquette is ensured by the strength of the indurated surface and the thermal stability of the binder at its core. The mathematical simulation performed for the horizontal-grate machine No. 3 at the Mikhailovsky Mining and Processing Plant showed that the replacement of a standard bed comprising indurated iron ore pellets having a temperature of 80℃ with briquettes having a temperature of 15℃ increases the capacity of this machine by 25% (up to 583 daN/pellet) and reduces the specific consumption of natural gas during iron ore pellet firing by 8.3% (up to 8.8 m3/t) while maintaining the quality of the main product – the strength index. The obtained results confirm the feasibility of using briquettes of all tested compositions as an artificial bottom bed in horizontal-grate machines, demonstrating their key thermophysical advantage – heat loss reduction in the grate zone.

Abstract Background Iron (Fe) oxides are vital for the stability of soil organic carbon (SOC) in wetlands, yet their impact on SOC stability in mangrove wetlands with varying salinity levels remains unclear. In this study, the effects of hematite treatment on soil Fe oxides, biological properties and SOC stability were investigated by adding 0%, 10%, 20% and 50% hematite to low- and high-salinity mangrove soils on the basis of initial total soil Fe content (50 mg g −1 ). Results The results showed that hematite treatments regulated SOC stability mainly by altering Fe-bound organic carbon (OC-Fe), rather than directly affecting SOC content. In high-salinity soils, the hematite treatment increased OC-Fe from 40.64 to 70.07% by promoting the formation of low-crystalline and short-range ordered Fe oxides, dissolved organic carbon preservation, and microbial biomass reduction. In contrast, the hematite treatment reduced the OC-Fe content by 16.06–35.58% by promoting microbial utilization of natural OC-Fe complexes in low-salinity soils. In addition, only the 20% hematite addition treatment increased carbon emissions from low-salinity soils by 22.96%, while all other treatments reduced soil carbon emissions by 4.77–24.48%. Conclusions This study highlights the effects of Fe minerals on SOC stability in mangrove wetlands under different salinities, and provides new insights into the study of carbon storage in different types of mangrove wetlands.

Spatial planning is commonly conceptualised as a regulatory mechanism for managing competing land uses; however, this perspective tends to obscure how planning actively shapes land use. Responding to calls for relational approaches to land, this article examines how spatial planning enacts mineral extraction through embedded socio-material relations. Drawing on assemblage thinking and a qualitative case study of the Pajala iron ore mine in northern Sweden, the analysis traces three interrelated planning practices: ‘filling and emptying' land, mobilising history and shaping interest and accelerating extraction, which configure land as a site of extraction. The article reveals that planning does not merely manage land but mobilises technical artefacts, historical narratives and urgency claims to enact mineral extraction as a matter of ‘public interest,' while constraining deliberative spaces and depoliticising value conflicts. The article advances a relational and practice-oriented perspective on spatial planning, which challenges essentialist notions of land and highlights planning’s role in reproducing extractive logics under the guise of sustainability. These insights underscore the need for planning scholarship to critically engage with the paradox of the green transition: achieving decarbonisation through intensified mineral extraction while ensuring that spatial planning contributes to more equitable and sustainable trajectories rather than reinforcing extractive imperatives.

Comprehensive Utilization of Iron Ore Tailings: a Review of Sustainable Practices and Technologies

Continuous control of smuggling in trains carrying iron ore with a neutron scanner based on T(d,n) neutron source: Monte Carlo simulations and experimental verification

Generally composite materials are made up of the two or more constituent materials. Now a day’s used various applications in society. Synthetic fibers have best properties compared to the materials. Composites materials are very stronger, lighter and less expensive compared to the traditional materials. Mostly synthetic fibers have good elasticity properties and present days FRP composites are used in almost all type of advanced engineering Applications structure like aircraft, boats, missile etc.., better mechanical properties like tensile strength, flexural strength, hardness and impact strength. The aim of the project is fabrication and testing of Aramid, Boron, Carbon fiber Reinforcement of iron ore powder combination of Aramid, Boron, Carbon fiber, Aramid + Boron, Boron + Carbon fiber, Aramid +Carbon fiber and Aramid +Boron+ Carbon fiber commonly used every composition iron ore powder using hand layup technique finally find out the tensile strength, flexural strength, impact strength and hardness compared to the 7 combinations finally find out the best composition of material among all compositions for real world applications. After all the tests has performed on the specimens the Boron+Carbon+Aramid+ iron ore powder shows a best result in the tensile strength (0.36 N/mm2), impact strength (78.5 J), hardness test (40) and as well as flexural strength (84.94 N/mm2). For the above investigations we are proposed the Boron+Carbon+Aramid+iron ore powder having good mechanical properties when comparing with other results

Hyperspectral imaging has been widely used in geoscience from space satellites to laboratory equipment due to its huge potential in qualifying and quantifying minerals. However, hyperspectral imaging has also experienced difficulties in detailed ore grade estimations due to its spectral complexity. To address this complexity, this paper presents an iron ore grade prediction method that combines hyperspectral imaging and a deep learning-based Convolutional Neural Network (CNN) prediction model. Hyperspectral images of different grades of iron ore were acquired, followed by training the prediction model using these hyperspectral images. The CNN model was trained using 100,000 spectra. Post-training prediction results show that the CNN model outperformed conventional models in all evaluation metrics which were 0.974, 2.714, and 11.226 in R<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>, validation RMSE, and test RMSE respectively. The analysis results of the trained CNN model furthermore suggested that the model successfully extract spectral features. Lastly, the results demonstrate an outstanding prediction capability for the iron ore grade by utilizing a CNN and Visible Near-Infrared (VNIR) hyperspectral imaging for the artificially prepared iron ore samples in the laboratory. Hence, the CNN-based model offers the potential in hyperspectral imaging to efficiently predict ore grade in geological remote sensing applications.

Phosphorus-goethite interactions: A review of mechanisms, environmental implications, and industrial relevance.

For nearly three decades, Russia’s industrial regions, especially the far-flung and remote Arctic areas surrounding Norilsk and the vast industrialized Ural region, have been subject to significant and continuing environmental damage; this is true even though there have been periodic national and regional efforts to clean-up pollution and enforce pollution controls. These are areas of significant resource extraction and heavy industry, where the level of airborne toxic chemicals such as sulfur dioxide, the presence of heavy metals in soils and waterways, the effect of acid rain causing forest kill off, and the general destruction of the landscape due to mining and smelting activity all exist in varying degrees. This paper will provide a synthesis of some of the major geographical, historical and technological reasons why pollution continues to persist in these areas. In particular, it will examine how the enduring location-based advantage of having large mineral resource deposits (including large amounts of nickel, copper, palladium and iron ore) in combination with aging Soviet-era infrastructure, long-established patterns of industrial production and harsh climatic conditions have resulted in an almost insurmountable level of environmental harm. For example, the Arctic's low temperature and stable air layers trap pollutants close to their point of origin resulting in limited opportunity for natural dispersal; geographic remoteness also complicates the transportation of remedial materials and the removal of hazardous waste. In addition, the extreme winter weather in the Arctic makes the process of recovering contaminated soils and promoting plant growth and development difficult if not impossible, thus creating continuous cycles of contamination. The study highlights the combined effects of these elements, which explains why previous attempts at mitigating the environmental impacts of these areas through modernization and enforcement mechanisms have generally failed. Finally, the study identifies several important implications for environmental policy, including the need for multi-faceted approaches to addressing the economic reliance on these types of industries and developing adaptive strategies suitable to remote environments. Additionally, the study identifies potential avenues of research into sustainable industrial transition processes and climate-resilient remediation technologies.

ABSTRACTCave microbiomes represent a rich yet understudied source of chemical diversity with biotechnological properties. Microorganisms in these environments thrive under extreme conditions such as darkness, oligotrophy, and high concentrations of inorganic matter like iron ore. In this study, sediment samples were collected from the aphotic zone of a ferruginous cave in the National Forest of Carajás (Brazilian Amazon). Eight bacterial strains were isolated and taxonomically classified using 16S rRNA gene sequencing, revealing five genera: Serratia, Bacillus, Enterococcus, Aneurinibacillus, and Comamonas. Crude extracts from liquid cultures were analyzed using untargeted LC–MS/MS and processed through feature‐based molecular networking on the GNPS platform. The resulting network highlighted the production of structurally similar compound classes across different genera, including cyclopeptides, cholic acid derivatives, and indole alkaloids. Crude extracts were tested for cytotoxicity against HCT‐116 and 501mel tumor cell lines, with significant inhibition observed for extracts from Aneurinibacillus, Comamonas, and Enterococcus. Multivariate analysis linked cyclopeptide derivatives to cytotoxic activity. This study offers one of the first insights into the chemical potential of cave‐dwelling bacteria in Brazil and underscores their promise for future biotechnological exploration.

Steel production using direct‐reduced iron (DRI) in an electric arc furnace with natural gas has a lower carbon footprint compared to the blast furnace route (Bhaskar et al., 2019). When iron ore is reduced using hydrogen, the resulting product—H‐DRI—represents a key pathway to green steel and is increasingly used as a feedstock in industrial steelmaking processes. However, depending on the initial ore type and the reduction conditions, hydrogen direct‐reduced iron poses significant explosion hazards, particularly in a dust form. Therefore, understanding the parameters governing the explosibility of H‐DRI dust is essential for ensuring safe handling and processing. This study investigates the influence of particle size distribution on the explosion behavior of H‐DRI dust. Precise size classification revealed an explosibility threshold of 71 μm. Mixture experiments demonstrated that the explosibility of polydisperse H‐DRI dusts is determined by the mass fraction of fine, reactive particles, whereas the inerting effect of coarse particles depends on their mass fraction rather than their specific size range. During the investigations, the influence of the igniters on the explosion development was also identified as a critical factor, as the ignition source contributes substantially to the measured rate of pressure rise. It was found that the second pressure peak correlates more reliably with the actual combustion dynamics of H‐DRI dust and therefore provides a more representative evaluation parameter for low‐reactivity materials, such as H‐DRI dust. These findings suggest that the current European test standard, EN 14034‐2, should be revised to account for igniter‐induced effects when characterizing dust explosion severity. Incorporating such improvements would enhance the assessment of low‐reactivity dusts and support the development of safer operational guidelines and risk mitigation strategies in H‐DRI‐related industries.

The progressive decarbonization of the steel industry is being undertaken through the transformation of blast furnace operations, notably through the reduction of coke consumption. Lower coke rates may affect gas permeability in the cohesive zone, a viscous and impermeable layer formed by the softening and melting of iron-bearing materials. Controlling the cohesive zone, its shape, thickness, and permeability, is essential for efficient blast furnace performance. The choice of adapted raw materials, i.e. their softening and melting properties, is a straightforward way to control the cohesive zone and to increase permeability. This study investigates the melting behavior of iron ore pellets with varying chemical compositions (acidic vs. fluxed) under conditions representative of the cohesive zone. Pellets were pre-reduced using the BORIS® counter-current pilot up to 1000 °C under representative conditions of the blast furnace. Reduced pellets were then subjected to melting tests via differential thermal analysis (DTA) and quenching furnace experiments. These analyses make it possible to better understand the softening and melting behavior of pellets in a blast furnace and results show that basic pellets generate less liquid phase at high temperatures, improving mechanical properties and improved reductive gas distribution. This result also implies a deeper and thinner cohesive zone inside the blast furnace. Attention was paid to the microstructure of the iron ores as the deformation of reduced materials is triggered by the partial melting of pellets and the formation of primary slag. Results also indicate that thermodynamic modelling could be a suitable and rapid tool to anticipate the behavior of different pellets at the cohesive zone level of blast furnaces, though existing databases must be refined to better reflect real phase equilibria in commercial iron ores.

The transition to green steel production faces a critical challenge: the raw material gap caused by the limited availability of high-grade iron ores required for direct reduction (DR) and electric arc furnace (EAF) steelmaking routes. Most globally available iron ores are lower grade, which, when processed in an EAF, leads to excessive slag formation, reduced yield and productivity, and increased energy consumption. Moreover, valorization of EAF slag for high value applications remains an unresolved issue. To address these limitations, a two-step process combining a Smelter and a basic oxygen furnace (BOF) is proposed. The Smelter enables efficient melting and final reduction of low-grade DRI under reducing conditions, achieving high iron yield and producing slag suitable for cement applications. The BOF refines the hot metal without altering existing plant logistics, avoiding costly re-certification. This configuration accommodates various DRI forms and metallization degrees, offering flexibility in DRI feedstock and energy optimization between DR and Smelter operations. Process validation tests in a 600 kg Smelter demonstrated successful processing of different DRI types and carbon carriers, achieving carbon contents above 3.5% in the hot metal and FeO levels below 1.5% in slag. Modeling indicates that the Smelter–BOF route can reduce CO 2 emissions by up to 78% compared to the conventional BF–BOF route when powered by renewable electricity. Furthermore, the Smelter provides a pathway for steelmaking slag valorization, enabling recovery of metallic fractions and modification of mineral phases for cement use. In conclusion, the Smelter–BOF route offers a promising solution to close the raw material gap in green steelmaking, supporting decarbonization, resource efficiency, and circular economy principles. Ongoing industrial projects, including Hy4Smelt and HYREX, confirm the feasibility of upscaling this technology for commercial deployment.

Role of humic acid in regulating reductive dechlorination: Modulating Fe(II) electronic-structure through antibonding eg* orbital occupancy.

Unveiling the unrecognized role of phytic acid in promoting hydroxyl radical generation during FeS colloids oxygenation: implications for organic matter mineralization.

The mining industry has a crucial role in a country’s development, contributing significantly to both economic and technological progress. However, mining activities often leave a negative impact on ecosystems. A promising approach to mitigate these effects and enhance the sustainability of building materials is to utilize these tailings in conjunction with sustainable binders such as geopolymers. Geopolymers are alkali-activated materials that exhibit properties comparable to Ordinary Portland Cement but offer superior sustainability benefits. This study explored the incorporation of four different tailings, derived from distinct areas of the same copper and iron sulfide mine, into geopolymer. The formulations were prepared by adding 0, 10, 20, and 30 wt% of each type of tailing. The investigation included compressive strength tests, mercury intrusion porosimetry, BET surface area analysis, microstructural characterization via scanning electron microscopy, and leaching tests. The results indicated that incorporating up to 20 % by weight of mine tailings had a negligible impact on compressive strength, maintaining values between 33 and 37 MPa after 90 days of curing. Generally, the addition of tailings led to an increase in mesopores and a reduction in micropores. Furthermore, after six months of curing, the geopolymeric matrix was found to immobilize harmful elements present in the tailings, such as sulfur, copper, iron, and others. These findings suggest that utilizing mining tailings in geopolymers offer advantages in physical properties and enhancing the sustainability of building materials. Moreover, this approach provides economic value to a mining by-product that would otherwise be discarded, thereby reducing environmental contamination. • Tailings with iron sulphate are more altered by alkaline activation than iron oxide. • Geopolymers with 20 % tailings exhibited a compressive strength between 33 and 37 MPa. • Tailings led to an increase in mesopores (96 %) and specific surface area (53 m 2 /g). • Geopolymers can capture harmful elements through the exchange of sodium cations.