International Journal of Mining Science and Technology最新文献_第3页

Flexible coal-derived carbon fibers via electrospinning for self-standing lithium-ion battery anodes 通过静电纺丝制备的柔性煤基碳纤维用于自立式锂离子电池阳极

IF 11.7 1区工程技术 Q1 MINING & MINERAL PROCESSING

International Journal of Mining Science and Technology

Pub Date : 2024-12-01 DOI: 10.1016/j.ijmst.2024.11.013

Baolin Xing , Weibo Meng , Hao Liang , Weiwei Kang , Huihui Zeng , Chuanxiang Zhang , Ishioma Laurene Egun , Peng Li , Yijun Cao , Zhengfei Chen

A series of flexible and self-standing coal-derived carbon fibers (CCFs) were fabricated through electrospinning coupled with carbonization using bituminous coal and polyacrylonitrile (PAN) as the carbon precursors. These CCFs were utilized as free-standing lithium-ion battery (LIB) anodes. Optimizing carbonization temperature reveals that the CCFs exhibit a one-dimensional solid linear structure with a uniform distribution of graphite-like microcrystals. These fibers possess a dense structure and smooth surface, with averaging diameter from approximately 125.0 to 210.0 nm at carbonization temperatures ranging from 600 to 900 °C. During electrospinning and carbonization, the aromatic rings enriched in bituminous coal crosslink with PAN chains, forming a robust three-dimensional (3D) framework. This 3D microstructure significantly enhances the flexibility and tensile strength of CCFs, while increasing the graphite-like sp² microcrystalline carbon content, thus improving electrical conductivity. The CCFs carbonized at 700 °C demonstrate an optimal balance of sp³ amorphous and sp² graphite-like carbons. The average diameter of CCFs-700 is 177 nm and the specific surface area (SSA) is 7.2 m²·g⁻¹. Additionally, the fibers contain oxygen-containing functional groups, as well as nitrogen-containing functional groups, including pyridinic nitrogen and pyrrolic nitrogen. Owing to its characteristics, the CCFs-700 showcases remarkable electrochemical performance, delivering a high reversible capacity of 631.4 mAh·g⁻¹. CCFs-700 also exhibit outstanding cycle stability, which retains approximately all of their first capacity (400.1 mAh·g⁻¹) after 120 cycles. This research offers an economical yet scalable approach for producing flexible and self-supporting anodes for LIBs that do not require current collectors, binders and conductive additives, thereby simplifying the electrode fabrication process.

以烟煤和聚丙烯腈（PAN）为碳前驱体，采用静电纺丝-炭化法制备了一系列柔性自立煤基碳纤维（CCFs）。这些CCFs被用作独立式锂离子电池（LIB）阳极。优化炭化温度后，CCFs呈现一维固体线性结构，微晶分布均匀。这些纤维具有致密的结构和光滑的表面，在600至900°C的碳化温度下，平均直径约为125.0至210.0 nm。在静电纺丝和炭化过程中，富含烟煤的芳香环与PAN链交联，形成坚固的三维骨架。这种三维微观结构显著提高了CCFs的柔韧性和抗拉强度，同时增加了类石墨sp2微晶碳含量，从而提高了导电性。在700°C碳化的CCFs中，sp3非晶碳和sp2类石墨碳达到了最佳平衡。CCFs-700的平均直径为177 nm，比表面积（SSA）为7.2 m2·g−1。此外，纤维中还含有含氧官能团和含氮官能团，包括吡啶氮和吡咯氮。因此，CCFs-700具有优异的电化学性能，可提供631.4 mAh·g−1的高可逆容量。CCFs-700还表现出出色的循环稳定性，在120次循环后保持大约所有的初始容量（40.1 mAh·g−1）。这项研究提供了一种经济且可扩展的方法来生产柔性和自支撑的锂离子电池阳极，不需要集流器、粘合剂和导电添加剂，从而简化了电极的制造过程。

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引用次数: 0

Accumulated damage failure mechanism of anchoring structures under cyclic impact disturbance 循环冲击扰动下锚固结构累积损伤破坏机制

IF 11.7 1区工程技术 Q1 MINING & MINERAL PROCESSING

International Journal of Mining Science and Technology

Pub Date : 2024-12-01 DOI: 10.1016/j.ijmst.2024.11.006

Peng Wang , Nong Zhang , Jiaguang Kan , Qun Wei , Zhengzheng Xie , Aoran Li , Zhe He , Jinghua Qi , Xingliang Xu , Changrui Duan

Cyclic impact induces ongoing fatigue damage and performance degradation in anchoring structures, serving as a critical factor leading to the instability of deep roadways. This paper takes the intrinsic spatiotemporal relationship of macro-microscopic cumulative damage in anchoring structures as the main thread, revealing the mechanism of bearing capacity degradation and progressive instability of anchoring structure under cyclic impact. Firstly, a set of impact test devices and methods for the prestressed solid anchor bolt anchoring structure were developed, effectively replicating the cyclic impact stress paths in situ. Secondly, cyclic impact anchoring structure tests and simulations were conducted, which clarifies the damage evolution mechanism of the anchoring structure. Prestress loss follows a cubic decay function as the number of impacts increases. Under the same impact energy and pretension force, the impact resistance cycles of extended anchoring and full-length anchoring were increased by 186.7% and 280%, respectively, compared to end anchoring. The rate of internal damage accumulation is positively correlated with impact energy and negatively correlated with anchorage length. Internal tensile cracks account for approximately 85%. Stress transmission follows a fluctuating pattern. Compared to the extended anchoring, the maximum vibration velocity of the exposed end particles in the full-length anchoring was reduced by 59.31%. Damage evolution exhibits a pronounced cumulative mutation effect. Then, a three-media, two-interface mechanical model of the anchoring structure was constructed. It has been clarified that the compressive stress, tensile stress, and oscillation effect arising from rapid transitions between compression and tension are the primary internal factors responsible for the degradation of the anchoring structure’s bearing capacity. Finally, the progressive instability mechanism of the anchoring structure under cyclic impact was elucidated. The mutual feedback and superposition of media rupture, interface debonding, and bearing capacity degradation result in overall failure. The failure process involves stages dominated by oscillation-compression, tensile stress, and compression failure. A targeted control strategy was further proposed. This provides a reference for maintaining the long-term stability of deep roadways under dynamic impact loads.

循环冲击引起锚固结构的持续疲劳损伤和性能退化，是导致深部巷道失稳的关键因素。本文以锚固结构宏微观累积损伤的内在时空关系为主线，揭示了循环冲击作用下锚固结构承载力退化和逐渐失稳的机理。首先，开发了一套预应力实体锚杆锚固结构冲击试验装置和方法，有效地模拟了原位循环冲击应力路径；其次，进行了循环冲击锚固结构试验与模拟，阐明了锚固结构的损伤演化机理。随着冲击次数的增加，预应力损失服从三次衰减函数。在相同的冲击能量和预紧力下，延长锚固和全长锚固的抗冲击周期分别比端部锚固提高了186.7%和280%。内部损伤累积速率与冲击能量呈正相关，与锚固长度负相关。内部拉伸裂纹约占85%。应力传递遵循波动模式。与延长锚固相比，全长锚固中暴露端粒的最大振动速度降低了59.31%。损伤进化表现出明显的累积突变效应。然后，建立了锚固结构的三介质双界面力学模型。研究表明，压应力、拉应力以及压拉快速转换产生的振荡效应是导致锚固结构承载力退化的主要内部因素。最后，分析了循环冲击作用下锚固结构的渐进性失稳机理。介质破裂、界面剥离、承载力退化三者相互反馈叠加，导致整体破坏。破坏过程包括以振荡压缩、拉应力和压缩破坏为主的阶段。进一步提出了有针对性的控制策略。为深埋巷道在动冲击荷载作用下保持长期稳定提供参考。

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引用次数: 0

Enhancement of 2-hydroxy-3-naphthyl hydroxamic acid adsorption on bastnaesite and monazite surfaces using H2O2 pre-oxidation for improved flotation process

IF 11.7 1区工程技术 Q1 MINING & MINERAL PROCESSING

International Journal of Mining Science and Technology

Pub Date : 2024-11-01 DOI: 10.1016/j.ijmst.2024.10.007

Weiwei Wang , Zhengyao Li , Anhua Zou , Kai Gao , Weiyao Zhu , Shaochun Hou , Chunlei Guo , Yuanyuan Wang

Rare earth elements have been widely applied in various sectors. Bastnaesite and monazite are crucial rare earth minerals, and flotation is a vital technique for recovering fine-grained rare earth minerals and separating them from associated gangue minerals such as fluorite and apatite. Flotation collectors play a key role in selectively adsorbing valuable minerals, enhancing their surface hydrophobicity, which has prompted considerable research interest. However, the interaction between minerals and reagents relies on the reactivity and selectivity of the reagent groups, as well as the reactive properties of the surface atoms of the minerals. This study proposes the use of H₂O₂ oxidation to enhance the flotation process of rare earth minerals. The flotation experiments demonstrated that pre-adding H₂O₂ before introducing the flotation collector significantly improved the grade and recovery of rare earth concentrates. The adsorption mechanisms of 2-hydroxy-3-naphthyl hydroxamic acid collector on rare earth mineral surfaces before and after H₂O₂ pre-oxidation were studied. The 2-hydroxy-3-naphthyl hydroxamic acid interacts with Ce³⁺ on the surface of unoxidized rare earth minerals, forming chelate compounds with five-membered ring structures. The H₂O₂ exhibited potent oxidizing properties and oxidized the Ce³⁺ on the bastnaesite and monazite surfaces to more stable Ce⁴⁺, which demonstrated stronger binding capability with hydroxamic acid.

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引用次数: 0

IFC: Editorial

IF 11.7 1区工程技术 Q1 MINING & MINERAL PROCESSING

International Journal of Mining Science and Technology

Pub Date : 2024-11-01 DOI: 10.1016/S2095-2686(24)00164-2

引用次数: 0

Selective flocculation-flotation of ultrafine hematite from clay minerals under asynchronous flocculation regulation 非同步絮凝调控下粘土矿物中超细粒赤铁矿的选择性絮凝浮选

IF 11.7 1区工程技术 Q1 MINING & MINERAL PROCESSING

International Journal of Mining Science and Technology

Pub Date : 2024-11-01 DOI: 10.1016/j.ijmst.2024.11.004

Fusheng Niu , Yuying Chen , Jinxia Zhang , Fei Liu , Ziye Wang

The clay mineral flocculation encapsulation poses a major technical challenge in the field of fine mineral separation. Enhancing the ability to separate clay minerals from target mineral surfaces is key to addressing this issue. In the flotation process of ultrafine hematite, sodium polyacrylate (PAAS) was used as a selective flocculant for hematite, polyaluminum chloride (PAC) as a flocculant for kaolinite and chlorite, and sodium oleate (NaOL) as the collector to achieve asynchronous flocculation flotation. This study examines the flotation separation performance and validates it through experiments on actual mineral samples. The results indicate that with PAAS and PAC dosages of 1.25 and 50 mg·L⁻¹, respectively, the iron grade and recovery of the actual mineral samples increased by 9.39% and 7.97%. Through Zeta potential, XPS analysis, infrared spectroscopy, and total organic carbon (TOC) testing, the study reveals the microscopic interaction mechanisms of different flocculants with minerals, providing insights for the clean and efficient utilization of ultrafine mineral resources.

粘土矿物絮凝包封是精细矿物分选领域的一大技术难题。提高从目标矿物表面分离粘土矿物的能力是解决这一问题的关键。在超细粒赤铁矿浮选过程中，采用聚丙烯酸钠（PAAS）作为赤铁矿的选择性絮凝剂，聚氯化铝（PAC）作为高岭石和绿泥石的絮凝剂，油酸钠（NaOL）作为捕收剂，实现了非同步絮凝浮选。本研究考察了浮选分离的性能，并通过对实际矿物样品的实验进行了验证。结果表明，PAAS用量为1.25和PAC用量为50 mg·L−1时，实际矿物样品的铁品位和回收率分别提高了9.39%和7.97%。通过Zeta电位、XPS分析、红外光谱和总有机碳（TOC）测试，揭示了不同絮凝剂与矿物的微观相互作用机理，为超细矿物资源的清洁高效利用提供了思路。

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引用次数: 0

Influence mechanism of Fe3+ doping on the hydrophobic regulation of kaolinite/water interface: Experiments and MD simulations Fe3+掺杂对高岭石/水界面疏水调控的影响机理：实验与MD模拟

IF 11.7 1区工程技术 Q1 MINING & MINERAL PROCESSING

International Journal of Mining Science and Technology

Pub Date : 2024-11-01 DOI: 10.1016/j.ijmst.2024.10.005

Jun Chen , Huanhuan Shang , Yunjia Ling , Feifei Jia , Yali Cheng , Fanfei Min

The surface/interfacial reactivity of clay is a critical factor influencing the sedimentation of coal slurry water. To achieve efficient sedimentation of coal slurry water, this paper introduces a novel approach that regulates the hydrophobicity of defective active sites in clay minerals. Fe³⁺-doped kaolinite (Fe³⁺-Kao) was synthesized by hydrothermal methods. Subsequently, tests were conducted on the adsorption capacity, surface wettability, and agglomeration sedimentation of alkyl amine/ammonium salts (AAS) on Fe³⁺-Kao surfaces. Fe³⁺ doping significantly enhances AAS adsorption and alters surface properties from hydrophilic to hydrophobic, promoting kaolinite particle aggregation and sedimentation, thereby improving coal slurry water treatment efficiency. Molecular dynamics (MD) simulations were performed to analyze the statistical adsorption behavior of AAS on Fe³⁺-Kao surfaces. The simulation results indicate that the mechanism by which Fe³⁺ doping influences the hydrophobic regulation of kaolinite surfaces is due to the enhanced interfacial interactions between the kaolinite surface and AAS, where the interfacial effects are more pronounced on surfaces closer to the dopant sites. The findings of this research offer valuable insights for future studies on other types of lattice defects in clay minerals, as well as for the development of more efficient treatment chemicals for coal slurry water.

粘土的表面/界面反应性是影响煤浆水沉降的关键因素。为了实现煤浆水的高效沉降，本文介绍了一种调节粘土矿物中缺陷活性位点疏水性的新方法。采用水热法合成了Fe3+掺杂高岭石（Fe3+-Kao）。随后，对烷基胺/铵盐（AAS）在Fe3+-Kao表面的吸附能力、表面润湿性和团聚沉降进行了测试。Fe3+的掺杂显著增强了AAS的吸附，使表面性质由亲水性变为疏水性，促进了高岭石颗粒的聚集和沉降，从而提高了煤浆水处理效率。通过分子动力学（MD）模拟分析了AAS在Fe3+-Kao表面的统计吸附行为。模拟结果表明，Fe3+掺杂影响高岭石表面疏水调节的机理是由于高岭石表面与AAS之间的界面相互作用增强，其中界面作用在靠近掺杂点的表面上更为明显。本研究的发现为今后对粘土矿物中其他类型晶格缺陷的研究以及开发更有效的煤浆水处理化学品提供了有价值的见解。

{"title":"Influence mechanism of Fe3+ doping on the hydrophobic regulation of kaolinite/water interface: Experiments and MD simulations","authors":"Jun Chen , Huanhuan Shang , Yunjia Ling , Feifei Jia , Yali Cheng , Fanfei Min","doi":"10.1016/j.ijmst.2024.10.005","DOIUrl":"10.1016/j.ijmst.2024.10.005","url":null,"abstract":"<div><div>The surface/interfacial reactivity of clay is a critical factor influencing the sedimentation of coal slurry water. To achieve efficient sedimentation of coal slurry water, this paper introduces a novel approach that regulates the hydrophobicity of defective active sites in clay minerals. Fe<sup>3+</sup>-doped kaolinite (Fe<sup>3+</sup>-Kao) was synthesized by hydrothermal methods. Subsequently, tests were conducted on the adsorption capacity, surface wettability, and agglomeration sedimentation of alkyl amine/ammonium salts (AAS) on Fe<sup>3+</sup>-Kao surfaces. Fe<sup>3+</sup> doping significantly enhances AAS adsorption and alters surface properties from hydrophilic to hydrophobic, promoting kaolinite particle aggregation and sedimentation, thereby improving coal slurry water treatment efficiency. Molecular dynamics (MD) simulations were performed to analyze the statistical adsorption behavior of AAS on Fe<sup>3+</sup>-Kao surfaces. The simulation results indicate that the mechanism by which Fe<sup>3+</sup> doping influences the hydrophobic regulation of kaolinite surfaces is due to the enhanced interfacial interactions between the kaolinite surface and AAS, where the interfacial effects are more pronounced on surfaces closer to the dopant sites. The findings of this research offer valuable insights for future studies on other types of lattice defects in clay minerals, as well as for the development of more efficient treatment chemicals for coal slurry water.</div></div>","PeriodicalId":48625,"journal":{"name":"International Journal of Mining Science and Technology","volume":"34 11","pages":"Pages 1575-1586"},"PeriodicalIF":11.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Advancing green flotation: Separation of Cu-Pb minerals through the application of eco-friendly organic double reaction group depressant

IF 11.7 1区工程技术 Q1 MINING & MINERAL PROCESSING

International Journal of Mining Science and Technology

Pub Date : 2024-11-01 DOI: 10.1016/j.ijmst.2024.11.005

Siqi Yang , Xianping Luo , Rufeng Chen , Louyan Shen , Xun Fan , Jiancheng Miao , Xuekun Tang

Achieving efficient flotation separation of chalcopyrite and galena while maintaining environmental friendliness poses a challenge. This study utilized the environmentally friendly copolymer acrylic acid-2-acrylamide-2-methylpropanesulfonic acid (AA/AMPS) as a depressant to separate chalcopyrite and galena. Flotation tests revealed a significant reduction in galena recovery when AA/AMPS was employed, with minimal impact observed on chalcopyrite. In artificial mixed ore flotation, AA/AMPS was found to enhance the efficiency of copper and lead separation, surpassing K₂Cr₂O₇. Furthermore, the effectiveness of AA/AMPS in facilitating copper-lead separation has been validated in practical ore flotation. The presence of AA/AMPS inhibited the adsorption of SBX onto galena, as confirmed by zeta potential and contact angle measurements. However, the adsorption on chalcopyrite remained unaffected. Through analyses using Atomic Force Microscope, X-ray photoelectron spectroscopy, and Density Functional Theory, a robust chemical interaction between the reactive groups in AA/AMPS and Pb sites on galena was uncovered, resulting in the formation of a hydrophilic polymer layer. This layer impedes SBX adsorption and reduces galena’s floatability. In contrast, no significant chemical adsorption was observed between AA/AMPS and Cu and Fe sites on chalcopyrite, preserving its SBX affinity. Overall, AA/AMPS shows promise in replacing traditional depressants for Cu-Pb sulfide ore separation, enhancing environmental sustainability.

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引用次数: 0

Experimental study on permeability evolution of deep high-stressed coal under major horizontal stress unloading paths

IF 11.7 1区工程技术 Q1 MINING & MINERAL PROCESSING

International Journal of Mining Science and Technology

Pub Date : 2024-11-01 DOI: 10.1016/j.ijmst.2024.10.004

Chao Liu , Jiahao Zhang , Songwei Wu , Jinghua Qi , Beichen Yu , Liang Wang

Both bulk stress (σ_ii) and stress path (SP) significantly affect the transportation characteristics of deep gas during reservoir pressure depletion. Therefore, the experimental study of horizontal stress unloading on seepage behavior of gas-bearing coal under constant σ_ii-constraints is performed. The results show that coal permeability is affected by horizontal stress anisotropy (σ_H≠σ_h), and the contribution of minor horizontal stress to permeability is related to the differential response of horizontal strain. The slippage phenomenon is prominent in deep high-stress regime, especially in low reservoir pressure. σ_ii and SP jointly determine the manifestation of slippage effect and the strength of stress sensitivity (γ) of permeability. Deep reservoir implies an incremental percentage of slip-based permeability, and SP weakens the slippage effect by changing the elastic–plastic state of coal. However, γ is negatively correlated with slippage effect. From the Walsh model, narrow (low aspect-ratio) fractures within the coal under unloading SP became the main channel for gas seepage, and bring the effective stress coefficient of permeability (χ) less than 1 for both low-stress elastic and high-stress damaged coal. With the raise of the effective stress, the effect of pore-lined clay particles on permeability was enhanced, inducing an increase in χ for high-stress elastic coal.

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引用次数: 0

Evaluation of the migration and environmental effects of metal elements within cementitious gangue-fly ash backfill in underground coal mines

IF 11.7 1区工程技术 Q1 MINING & MINERAL PROCESSING

International Journal of Mining Science and Technology

Pub Date : 2024-11-01 DOI: 10.1016/j.ijmst.2024.11.002

Xuejie Deng , Yuan Jiao , Shicong Li , Nan Zhou , Yan An , Erol Yilmaz , Qingxue Zheng , Xifeng Liang

Cementitious gangue-fly ash backfill (CGB) is used as a green mining technology worldwide. However, under the coupled effects of geological stress and groundwater, the metal elements in the CGB tend to migrate into nearby strata, which can consequently result in pollution of the groundwater environment. In this paper, the influence of initial pH and stress damage on the migration behavior of metal elements in CGB is quantitatively studied through the multi-physical field coupling model of stress-permeability-concentration. The enhanced Nemerow index evaluation method is used to comprehensively evaluate the impact of these metal elements migration behaviors on the groundwater environment. The research results show that: (1) When the stress damage of the CGB increases from 0.76 to 0.95, the Darcy velocity at the bottom of the CGB first increases, then decreases, and finally stabilizes at 2.01×10⁻⁷ m/s. The longest time to reach the maximum Darcy velocity is 3 a. (2) When the damage of the CGB is 0.95, the farthest migration distances of Al, Cr, Mn, Fe, Ba, and Pb are 40.5, 34.0, 29.8, 32.9, 38.8 and 32.1 m, respectively. (3) The alkaline environment stimulates the migration of Al, Cr, Fe, Mn, and Pb, whereas Ba migrates farther under acidic conditions. The farthest migration distance of Ba is 31.6 m under pH 3. (4) The enhanced Nemerow index indicates that when stress damage increases from 0.76 to 0.95, the areas with poor water quality increase from 0 to 1.71%, and no area is classified as very poor grade. When the initial pH changes from 3 to 11, 100% of the region is classified as fair or above. The initial pH of the CGB has a relatively slight influence on the groundwater environment. This study provides experimental data and theoretical basis for the environmental evaluation of CGB.

{"title":"Evaluation of the migration and environmental effects of metal elements within cementitious gangue-fly ash backfill in underground coal mines","authors":"Xuejie Deng , Yuan Jiao , Shicong Li , Nan Zhou , Yan An , Erol Yilmaz , Qingxue Zheng , Xifeng Liang","doi":"10.1016/j.ijmst.2024.11.002","DOIUrl":"10.1016/j.ijmst.2024.11.002","url":null,"abstract":"<div><div>Cementitious gangue-fly ash backfill (CGB) is used as a green mining technology worldwide. However, under the coupled effects of geological stress and groundwater, the metal elements in the CGB tend to migrate into nearby strata, which can consequently result in pollution of the groundwater environment. In this paper, the influence of initial pH and stress damage on the migration behavior of metal elements in CGB is quantitatively studied through the multi-physical field coupling model of stress-permeability-concentration. The enhanced Nemerow index evaluation method is used to comprehensively evaluate the impact of these metal elements migration behaviors on the groundwater environment. The research results show that: (1) When the stress damage of the CGB increases from 0.76 to 0.95, the Darcy velocity at the bottom of the CGB first increases, then decreases, and finally stabilizes at 2.01×10<sup>−7</sup> m/s. The longest time to reach the maximum Darcy velocity is 3 a. (2) When the damage of the CGB is 0.95, the farthest migration distances of Al, Cr, Mn, Fe, Ba, and Pb are 40.5, 34.0, 29.8, 32.9, 38.8 and 32.1 m, respectively. (3) The alkaline environment stimulates the migration of Al, Cr, Fe, Mn, and Pb, whereas Ba migrates farther under acidic conditions. The farthest migration distance of Ba is 31.6 m under pH 3. (4) The enhanced Nemerow index indicates that when stress damage increases from 0.76 to 0.95, the areas with poor water quality increase from 0 to 1.71%, and no area is classified as very poor grade. When the initial pH changes from 3 to 11, 100% of the region is classified as fair or above. The initial pH of the CGB has a relatively slight influence on the groundwater environment. This study provides experimental data and theoretical basis for the environmental evaluation of CGB.</div></div>","PeriodicalId":48625,"journal":{"name":"International Journal of Mining Science and Technology","volume":"34 11","pages":"Pages 1551-1562"},"PeriodicalIF":11.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143198112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Instability mechanisms of slope in open-pit coal mines: From physical and numerical modeling

IF 11.7 1区工程技术 Q1 MINING & MINERAL PROCESSING

International Journal of Mining Science and Technology

Pub Date : 2024-11-01 DOI: 10.1016/j.ijmst.2024.10.003

Guanghe Li , Zihuan Hu , Dong Wang , Laigui Wang , Yanting Wang , Lichun Zhao , Hongjun Jia , Kun Fang

The stability of open-pit mine slopes is crucial for safe and efficient mining operations. However, the presence of weak interlayers poses significant challenges in maintaining the stability of slopes. To explore the impact of the rock arching effect on slopes during excavation, understand the deformation zones and evaluation stages in such environments, and analyze the formation and characteristics of cracks, this study investigated the instability mechanism of open-pit mine slopes with weak interlayers through physical and numerical modeling. Focusing on the Zaharnur open-pit coal mine in China as a prototype, a sophisticated physical model test employing particle image velocimetry and Brillouin optical frequency domain analysis was conducted to comprehensively analyze the displacement and strain variation characteristics of open-pit mine slopes. The displacement, strain, stress redistribution, and failure processes of slopes under excavation were comprehensively analyzed through physical and numerical modeling. The results showed that the slope model exhibited a strain pattern in which the strain incrementally increased from its center toward the edges, and the landslide thrust was converted into an internal force along the arch axis and transmitted to the supports. The concept of the rock arching effect specific to soft rocks was proposed, shedding new light on an important phenomenon specific to open-pit slopes with weak interlayers. Based on its deformation characteristics, the slope could be divided into three areas: The excavation influence area, the crack area and the failure area. In addition, the ratios of the height and width of the outermost cracks to the excavation width fluctuated in the ranges of 0.36–0.49 and 0.72–1.00, respectively. These findings contribute to a better understanding of the instability mechanisms in open-pit mine slopes with weak interlayers and provide valuable guidelines for safe mining practices.

{"title":"Instability mechanisms of slope in open-pit coal mines: From physical and numerical modeling","authors":"Guanghe Li , Zihuan Hu , Dong Wang , Laigui Wang , Yanting Wang , Lichun Zhao , Hongjun Jia , Kun Fang","doi":"10.1016/j.ijmst.2024.10.003","DOIUrl":"10.1016/j.ijmst.2024.10.003","url":null,"abstract":"<div><div>The stability of open-pit mine slopes is crucial for safe and efficient mining operations. However, the presence of weak interlayers poses significant challenges in maintaining the stability of slopes. To explore the impact of the rock arching effect on slopes during excavation, understand the deformation zones and evaluation stages in such environments, and analyze the formation and characteristics of cracks, this study investigated the instability mechanism of open-pit mine slopes with weak interlayers through physical and numerical modeling. Focusing on the Zaharnur open-pit coal mine in China as a prototype, a sophisticated physical model test employing particle image velocimetry and Brillouin optical frequency domain analysis was conducted to comprehensively analyze the displacement and strain variation characteristics of open-pit mine slopes. The displacement, strain, stress redistribution, and failure processes of slopes under excavation were comprehensively analyzed through physical and numerical modeling. The results showed that the slope model exhibited a strain pattern in which the strain incrementally increased from its center toward the edges, and the landslide thrust was converted into an internal force along the arch axis and transmitted to the supports. The concept of the rock arching effect specific to soft rocks was proposed, shedding new light on an important phenomenon specific to open-pit slopes with weak interlayers. Based on its deformation characteristics, the slope could be divided into three areas: The excavation influence area, the crack area and the failure area. In addition, the ratios of the height and width of the outermost cracks to the excavation width fluctuated in the ranges of 0.36–0.49 and 0.72–1.00, respectively. These findings contribute to a better understanding of the instability mechanisms in open-pit mine slopes with weak interlayers and provide valuable guidelines for safe mining practices.</div></div>","PeriodicalId":48625,"journal":{"name":"International Journal of Mining Science and Technology","volume":"34 11","pages":"Pages 1509-1528"},"PeriodicalIF":11.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143198372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0