{"title":"Review on High Phosphorous in Iron Ore: Problem and Way Out","authors":"Akhil Singh, Veerendra Singh, Sudipta Patra, Prashant Dixit, Asim Kumar Mukherjee","doi":"10.1007/s42461-024-01001-6","DOIUrl":"https://doi.org/10.1007/s42461-024-01001-6","url":null,"abstract":"<p>Phosphorous is an undesired element present in iron ore used in the steel making process. It leads to an increase in overall production cost as well as deteriorated steel quality. The desired phosphorus content in iron ores used in steel making is < 0.1%. Numerous beneficiation studies are mentioned in the literature; however, there is no commercial scale technology established to beneficiate high phosphorous iron. The major phosphorous bearing minerals are apatite (Ca<sub>5</sub>(PO<sub>4</sub>)(Cl/F/OH), wavellite (Al<sub>3</sub>(PO<sub>4</sub>)<sub>2</sub>(OH)<sub>3</sub>·5(H<sub>2</sub>O)), senegalite (Al<sub>2</sub>(PO<sub>4</sub>)(OH)<sub>3</sub>(H<sub>2</sub>O), barrandite ((Fe,Al)PO<sub>4</sub>·2H<sub>2</sub>O), etc. Ultrafine grinding is required to liberate phosphorous minerals from iron ore minerals and subsequently subject it to flotation, acid leaching, and bioprocessing. The selective flotation of iron ore could successfully reduce the phosphorous content from 0.82% to < 0.20% with the combination of grinding, magnetic separation, and carbothermic reduction. Acid leaching processes are also able to remove ~80% (0.85%→0.16%) of phosphorus; however, these are relatively costly and complex processes. The mechanism of bio-extraction for phosphorous removal is reported as one of the most successful processes. This process is capable of removing more than 80% of the total phosphorous and significantly reducing the phosphorous content from 1.06% to 0.16%. The main disadvantage of this process is that it occurs at a much slower pace. In today’s scenario, ultrafine grinding followed by froth flotation seems to be the most feasible solution for the beneficiation of high phosphorous iron ore in which the concentrate obtained can be utilized for pellet making and ultimately used for steel making processes. Development of additives for leaching, roasting, and bioprocessing can be explored further to make these processes more effective and economically viable.</p>","PeriodicalId":18588,"journal":{"name":"Mining, Metallurgy & Exploration","volume":"66 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141171459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
August Greth, Setareh Ghaychi Afrouz, Cigdem Keles, Emily Sarver
{"title":"Characterization of Respirable Coal Mine Dust Recovered from Fibrous Polyvinyl Chloride Filters by Scanning Electron Microscopy","authors":"August Greth, Setareh Ghaychi Afrouz, Cigdem Keles, Emily Sarver","doi":"10.1007/s42461-024-00999-z","DOIUrl":"https://doi.org/10.1007/s42461-024-00999-z","url":null,"abstract":"<p>The characterization of respirable dust on the basis of constituent fractions and particle sizes is increasingly of concern for evaluating exposure hazards. For high-resolution particle analysis, scanning electron microscopy with energy dispersive X-ray (SEM-EDX) can be an effective tool. However, it requires particles to be deposited on a smooth, uniform substrate such as a polycarbonate (PC) filter for optimal results. While direct sampling onto PC is possible, this is not the standard approach in many situations. For example, in coal mines, respirable dust samples have typically been collected onto polyvinyl chloride (PVC) filters because they are intended for gravimetric and/or infrared spectroscopy analysis. Such fibrous substrates are not ideal for SEM-EDX (or other microscopy), but an effective method to recover and redeposit the dust particles could render such samples suitable for the additional analysis. Here, we present a simple method and compare SEM-EDX results for paired samples analyzed directly on PC and following recovery from PVC and redeposition on PC. Both laboratory-generated dust samples (<i>n</i> = 10 pairs) and field samples of respirable coal mine dust (<i>n</i> = 44 pairs) are included in this study. Although some changes in particle size distributions were observed between samples analyzed directly and those that were recovered and redeposited prior to analysis, the results indicate the dust recovery method generally yields a representative sample in terms of mineral constituents. That said, results also highlighted the effects of high particle loading density on individual particle analysis. Considering all sample pairs, those with similar loading density between the directly analyzed and recovered sample tended to exhibit similar mineralogy distributions. This was generally the case for the lab-generated sample pairs, and the Freeman-Halton exact test of independence indicated that the samples in just three (of 10) pairs were in disagreement in terms of their mineralogy distributions. On the other hand, for the field samples, the directly analyzed sample often had higher loading density than the recovered sample; and the Freeman-Halton test showed that 25 (of 44) pairs were in disagreement. However, the effect of possible particle agglomeration on the directly analyzed samples cannot be ruled out—and exploration of this factor was beyond the scope of the current study.</p>","PeriodicalId":18588,"journal":{"name":"Mining, Metallurgy & Exploration","volume":"27 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141059950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Samuel Nowak, Taghi Sherizadeh, Mina Esmaeelpour, Paul Brooks, Dogukan Guner, Kutay Karadeniz, Gunnar Wurst, Alper Kirmaci
{"title":"Geomechanical Monitoring of an Underground Bulk Mining Operation Using a Novel Distributed Optical Fiber Strain Sensing Method","authors":"Samuel Nowak, Taghi Sherizadeh, Mina Esmaeelpour, Paul Brooks, Dogukan Guner, Kutay Karadeniz, Gunnar Wurst, Alper Kirmaci","doi":"10.1007/s42461-024-00991-7","DOIUrl":"https://doi.org/10.1007/s42461-024-00991-7","url":null,"abstract":"<p>As mines continue to deepen and become more expansive, active monitoring of larger volumes of rock mass will become more critical to calibrate numerical simulations and to ensure the safety of underground workers. Monitoring larger volumes of rock mass requires low-cost sensors which are simple in construction and installation. In this study, a novel hybrid optical fiber cable (HOFC) designed for use in distributed optical fiber sensing (DOFS) via grouted boreholes was employed to monitor a bulk mining operation in an underground metal mine. The HOFC was successfully used to monitor approximately 2.7 × 10<sup>3</sup> m<sup>3</sup> of rock mass above excavations surrounding a pillar removal area in which six large pillars were removed simultaneously. A total of six measurement boreholes (maximum depth of 22 m) were used to measure strain along the optical fiber during the pillar removal operation using the HOFC, allowing for 70 individual strain measurement points, which were constructed for under one US dollar each. Monitoring of the excavation area took place over a 44-day period after pillar removal. Extensional strains were noted in the areas closest to the removed pillars, while areas of compression were noted directly above the remaining pillar in the area. The results of the case study demonstrate that a low-cost optical fiber strain sensing network can be rapidly installed in a large excavation area and can provide highly sensitive strain measurements in a manner that would be cost-prohibitive via other methods.</p>","PeriodicalId":18588,"journal":{"name":"Mining, Metallurgy & Exploration","volume":"208 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140941859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Research on Blasting Damage Control of 90° Slit Charge Structure","authors":"Chenglong Xiao, Guoli Shi, Zhiwei Zhao, Chenxi Ding","doi":"10.1007/s42461-024-00922-6","DOIUrl":"https://doi.org/10.1007/s42461-024-00922-6","url":null,"abstract":"<p>This study investigates the directional blasting of a 90° slit charge structure using laboratory experiments and field tests. A 90° slit charge suitable for the corner of roadway is proposed. After the slit charge blasting, two long main cracks along the slit, and several short secondary cracks in other directions. The slit charge not only significantly reduces damage to the surrounding rock, but also improves the quality of the roadway contour. In addition, a comprehensive damage evaluation system of the roadway contour and the surrounding rock is constructed using digital image analysis, borehole televiewer, and CT scanning.</p>","PeriodicalId":18588,"journal":{"name":"Mining, Metallurgy & Exploration","volume":"40 3 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140928574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ahmed A. Eliwa, Amal E. Mubark, Ebrahim A. Gawad, Ahmed H. Orabi, Mona M. Fawzy
{"title":"Maximizing the Processing of Polymetallic Concentrates via Actinide Separation and Rare Earth Retrieval","authors":"Ahmed A. Eliwa, Amal E. Mubark, Ebrahim A. Gawad, Ahmed H. Orabi, Mona M. Fawzy","doi":"10.1007/s42461-024-00985-5","DOIUrl":"https://doi.org/10.1007/s42461-024-00985-5","url":null,"abstract":"<p>During the last decades, the growing demand for rare earth elements (REEs) has led to numerous recent studies to recover these elements from various bearing ores and wastes. Therefore, the recovery of REEs from Ras Baroud polymetallic concentrate has been investigated in the current study. Physical beneficiation for the Ras Baroud pegmatite sample was carried out, yielding a concentrate for euxenite (Y), fergusonite (Y), xenotime (Y), monazite (Ce), allanite, thorite, uranothorite, and Hf-zircon, which resulted in raising the concentrations of rare earth elements, Th, Zr, U, and Ti in the sample. Fusion digestion processes with sodium hydroxide were studied using the Conceived Predictive Diagonal (CPD) technique. The three experimental digestion groups proved the dissolution of 99.9, 95.6, 99.9, 52.5, and 0.47% for REEs, Th, U, Ti, and Zr, respectively, under fusion conditions of 723 K, 120 min, 1/1.5 ore/alkali ratio, and − 100-μm particle sizes. Fusion kinetics, isotherms, and thermodynamics were investigated using several suggested models, namely, pseudo reversible first order, uptake general model, and shrinking core model which matched well with the experimental digestion results. Selective recovery of actinide content from REE content of the digested concentrate chloride solutions was accomplished using solvent extraction with di-2-ethyl hexyl phosphoric acid. About 99.9, 99.9, and 4.2% extraction efficiencies for Th, U, and REEs were performed, respectively, using 0.3 mol/L solvent concentration in kerosene as a diluent, 1/2 organic to aqueous ratio, an aqueous pH of 0.2, and 15-min contact time. Thorium and uranium ions were stripped with sulfuric acid solution 2.5 mol/L with 94 and 98% stripping efficiency, respectively. A highly purified REE precipitate was obtained from the raffinate solutions. Zircon mineralization tailings were obtained as a by-product through the alkaline digestion process.</p>","PeriodicalId":18588,"journal":{"name":"Mining, Metallurgy & Exploration","volume":"149 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140887137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ebrahim F. Salmi, Tan Phan, Ewan J. Sellers, Thomas R. Stacey
{"title":"Expert Elicitation for the Resilient Design and Optimisation of Ultra-long Ore Passes for Deep Mass Mining","authors":"Ebrahim F. Salmi, Tan Phan, Ewan J. Sellers, Thomas R. Stacey","doi":"10.1007/s42461-024-00979-3","DOIUrl":"https://doi.org/10.1007/s42461-024-00979-3","url":null,"abstract":"<p>Extension of ore pass length has become increasingly critical for optimising energy-efficient underground mining operations. Long and ultra-long ore passes, spanning from 300 to 700 m, can significantly improve the functionality and viability of underground mass mining operations though suboptimal performance has an extremely adverse impact on production. The public domain lacks substantial information regarding the primary engineering, geological, and geotechnical risks and challenges associated with the design, implementation, operation, and maintenance of such long ore passes. Therefore, the aggregation of past experiences and the insights of experts assume paramount significance. An innovative methodology is introduced to address this evident data deficiency and to establish comprehensive guidelines for the resilient design of such lengthy ore passes — combining gap analysis with expert elicitation techniques. This equips design engineers with the necessary tools to formulate and adapt strategies for assessing the numerous challenges and uncertainties that invariably accompany their projects. Expert elicitation techniques are summarised, and a gap analysis is conducted with subject matter experts, from various countries, collating their extensive ore pass design experience, to create a comprehensive list of effective parameters and key risks that must be considered. Quantitative analysis of the survey results enabled the identification and ranking of the numerous factors affecting the design, operation, and maintenance of long and ultra-long ore passes and highlights the complex technical challenges (substantial damage from rock particle impact, increased dynamic mining stresses leading to failure, air-blasts and back blasts, dust, preferential flow, turbulent and dynamic material flow) that are uncommon in shorter ore passes. Additionally, increasing length heightens the probability of intersecting weak rock or discontinuities, leading to a higher risk of structural failure and instabilities. Faulting, folding, and large-scale structures are also critical geological factors to be considered in the design of such structures. The key geotechnical factor is also the rock type surrounding the pass. Experts highlighted the lack of clear guidelines for decision-making, resilient design, and construction so this work suggests future investigations to determine the complex interaction between the effective parameters, using approaches like the rock engineering system, discovery of cascading hazards, and optimal controls.</p>","PeriodicalId":18588,"journal":{"name":"Mining, Metallurgy & Exploration","volume":"168 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140887072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Metals Recovery from Spent Lithium-ion Batteries Cathode Via Hydrogen Reduction-water Leaching-carbothermic or Hydrogen Reduction Process","authors":"Tahereh Rostami, Behnam Khoshandam","doi":"10.1007/s42461-024-00988-2","DOIUrl":"https://doi.org/10.1007/s42461-024-00988-2","url":null,"abstract":"<p>In the present paper, the recovery of mixed spent cathodes is evaluated and performed through a hydrogen reduction process. Firstly, the lithium is isolated by the hydrogen reduction process as LiOH at 600 <span>(mathrm{^circ{rm C} })</span> for 15 min with 10% H<sub>2</sub> with a flow rate of 350 ml/min. In the second step, 98.37% Li is recovered through water-leaching of hydrogen reduction products at 100 <span>(mathrm{^circ{rm C} })</span> for 90 min with 50 ml/g. The filtration residual is reduced by using a carbothermic reduction process and a hydrogen reduction method. The first one is performed under an Ar atmosphere at 900 <span>(mathrm{^circ{rm C} })</span> for 210 min and the second one is conducted at 800 <span>(mathrm{^circ{rm C} })</span> for 150 min. The purer products are achieved using the hydrogen reduction method at lower temperatures and shorter holding times compared to a carbothermic reduction process with recovery percentages of 100%, 99.06%, and 70% for Ni, Co, and Mn, respectively. Given the importance of reducing the emission of toxic gases, the hydrogen reduction process is also a promising method for metal recycling. The obtained results also demonstrated that Li, Co, Ni, and Mn can be effectively separated from the mixed cathode material through the hydrogen reduction process as a sustainable and environmentally friendly recycling process. This study provides an impressive understanding of the hydrogen reduction process and valuable guidance for a larger-scale hydrogen reduction process.</p>","PeriodicalId":18588,"journal":{"name":"Mining, Metallurgy & Exploration","volume":"44 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140887726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Efficient Separation of Iron and Alumina in Red Mud Using Reduction Roasting and Magnetic Separation","authors":"Hongyang Wang, Yuqi Zhao, Zhiyong Lin, Leiting Shen","doi":"10.1007/s42461-024-00990-8","DOIUrl":"https://doi.org/10.1007/s42461-024-00990-8","url":null,"abstract":"<p>Gibbsite-type bauxite is the main material for alumina extraction by Bayer process globally, while the iron in red mud is difficult to use for the high alumina content. Therefore, the efficient separation of iron and alumina is the premise for the resource utilization of red mud. In this work, the separation of iron and alumina in red mud containing 47.45% Fe and 11.58% Al<sub>2</sub>O<sub>3</sub> was studied through reduction roasting followed by magnetic separation. The analysis methods of XRD, VSM, SEM, and EDS were used to investigate the phase transformation of red mud during reduction roasting. Results show that hematite can be firstly reduced into magnetite, and alumogoethite into magnetite and alumina. Then, the magnetite reduction undergoes the process of Fe<sub>3</sub>O<sub>4</sub>→FeO→Fe, while alumina can react with FeO to form hercynite. The hercynite is ultimately reduced into metallic iron and alumina at elevated temperature. The specific saturation magnetization of reduced product is closely related to its main minerals, that is, the specific saturation magnetization of magnetite and metallic iron is higher than that of wustite and hercynite. The mass ratio of Fe to Al<sub>2</sub>O<sub>3</sub> in magnetic concentrate increases with roasting temperature, from 4.55 at 600 °C to 10.27 at 1200 °C. Therefore, efficient separation of iron and alumina in red mud could be achieved through deep reduction-magnetic separation.</p>","PeriodicalId":18588,"journal":{"name":"Mining, Metallurgy & Exploration","volume":"17 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140887052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Impacts of Grade Distribution and Economies of Scale on Cut-off Grade and Capacity Planning","authors":"Mehmet Balci, Mustafa Kumral","doi":"10.1007/s42461-024-00982-8","DOIUrl":"https://doi.org/10.1007/s42461-024-00982-8","url":null,"abstract":"<p>Strategic mine planning centers on solving cut-off grade selection, capacity planning, and block sequencing. Even though significant knowledge has been accumulated on mine planning over the last decades, there is still potential to add value to mineral sourcing by addressing various aspects. To this end, this paper addresses two issues. The effects of (1) grade/metal distribution within a mineral deposit and (2) the economies of scale (EoS) are explored in cut-off grade selection and capacity planning. In doing so, the interdependency between cut-off grade selection and capacity planning is also considered. A case study is implemented on a metallic deposit whose grade distribution exhibits lognormal distribution to detect if grade/metal distribution influences cut-off grade selection. Also, based on the same ore tonnage and metal quantity, six different datasets are generated with different shape and scale factors. The research outcomes indicate that deposits with lower shape and scale factors of lognormal distribution are more sensitive to metal price and discount rate changes because slight cut-off grade variations significantly change net present value (NPV). While the NPV of the deposit with the largest shape factor is $3,208,112,841 with a cut-off grade of 0.058 oz/tonne, the NPV of the deposit with the smallest shape factor is $93,617,240 with a cut-off grade of 0.027 oz/tonne. Furthermore, the case study is directed to investigate the effect of EoS on a project’s value, with a specific emphasis on the ratio of variable cost to total cost (capacity factor). Two different regression analyses are conducted based on the proposed model for optimal capacity planning and cut-off grade selection, respectively. In the first one, the absolute standardized beta values for EoS of mining and mineral processing costs are 0.736 and 0.425, meaning that capacity planning is highly sensitive to the EoS of mining and mineral processing operating costs. Meanwhile, the absolute standardized beta value for grade variability is 0.054 which means that the effects of grade variability and metal distribution are almost negligible for capacity planning. However, EoS is the most critical variable for capacity optimization. In the second regression analysis, the standardized beta values for grade variability and EoS of mineral processing operating cost are 0.573 and 0.522, so their effects on cut-off grade selection become vital.</p>","PeriodicalId":18588,"journal":{"name":"Mining, Metallurgy & Exploration","volume":"41 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140812193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Research on the Mechanical Characteristics of Thick Alluvium on the Surface Subsidence Features of Thin Bedrock Deposits at Depth","authors":"Shanxi Wu, Zhaohui Wang, Jialong Li, Haoyu Hu, Bochao An, Jiqing He, Shenyi Zhang","doi":"10.1007/s42461-024-00989-1","DOIUrl":"https://doi.org/10.1007/s42461-024-00989-1","url":null,"abstract":"<p>There are a large number of thick alluvium and thin bedrock deposits at depth in the Henan coal base. The degree of surface mining is high, and the surface environment is seriously damaged. Using indoor experiments, numerical simulation, and field measurement, it is studied the influence of the mechanical properties of thick alluvium on the surface subsidence characteristics of thick alluvium thin bedrock deposits at depth, taking Zhaogu No. 2 coal mine as the research background. The results show that the compressive strength and elastic modulus of the alluvial layer are linearly negatively correlated with the alluvial layer particle size, linearly positively correlated with the confining pressure, and nonlinearly positively correlated with the loading rate. The thickness of the alluvial layer has the greatest influence on the displacement of surface subsidence and the range of surface subsidence. The advancing mining rate of the working face has the greatest influence on the surface horizontal displacement. The mechanical properties of the alluvial layer affect the evolution characteristics of the caving arch and towering roof beam. The influence range of the 11012 working face is about 550 m, <i>β</i> is about 55.5°, and the maximum subsidence rate of the surface is 12 mm/day. The mining process and separation grouting can be adjusted to control the overburden displacement to reduce surface disturbance and protect the surface ecological environment. The research results of this paper can provide a research basis for the study of surface subsidence under similar geological conditions.</p>","PeriodicalId":18588,"journal":{"name":"Mining, Metallurgy & Exploration","volume":"23 8 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140811708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}