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

A new deformable cable for rock support in high stress tunnel: Steel pipe shrinkable energy-absorbing cable 用于高应力隧道岩石支护的新型可变形缆索：钢管收缩吸能电缆

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

International Journal of Mining Science and Technology

Pub Date : 2024-08-01 DOI: 10.1016/j.ijmst.2024.07.015

Xuezhen Wu , Mingzhu Zhao , Qing Ye , Yujing Jiang , Tao Deng , Hanfang Zheng , Gang Wang , Zhenchang Guan

High stress in surrounding rock will lead to serious problems, e.g., rock burst in hard rock and large deformation in soft rock. The applied support system under high in-situ stress conditions should be able to carry high load and also accommodate large deformation without experiencing severe damage. In this paper, a specially designed energy-absorbing component for rock bolt and cable that can solve the above problems was proposed. The energy-absorbing component can provide support resistance by plastic deformation of the metal including constraint annulus and compression pipe. For practical engineering, two forms were proposed. One was installed in the surrounding rock by reaming, and the other was installed directly outside the surrounding rock. During the dilation of the surrounding rock, the relative displacement of constraint annulus and compression pipe occurs, resulting in deformation resistance. Deformation resistance is transmitted to the rock bolt or cable, providing support resistance. The lab test and numerical simulation showed that the energy-absorbing component can perfectly achieve the large deformation effect, the deformation amount is as high as 694 mm, and the bearing capacity is stable at 367 kN. The field application tests were carried out in the mining roadway of Xinjulong coal mine, and the results showed that the new type of cable can ensure itself not to break under the condition of large deformation of the surrounding rock. The energy-absorbing component has the superiorities of performing large constant resistance and controllable deformation to effectively control the unpredictable disasters such as large deformation in soft rock and rock burst in hard rock encountered in deep strata.

围岩中的高应力会导致严重的问题，例如在硬岩中会出现岩爆，在软岩中会出现大变形。在高原位应力条件下应用的支撑系统应能承受高载荷，并能容纳大变形而不发生严重破坏。本文提出了一种专门设计的岩石螺栓和缆索吸能部件，可以解决上述问题。吸能部件可通过金属（包括约束环和压缩管）的塑性变形提供支撑阻力。在实际工程中，提出了两种形式。一种是通过扩孔安装在围岩中，另一种是直接安装在围岩外。在围岩扩张过程中，约束环和压缩管发生相对位移，产生变形阻力。变形阻力传递给岩石螺栓或电缆，提供支撑阻力。实验室试验和数值模拟表明，吸能部件可完美实现大变形效果，变形量高达 694 毫米，承载能力稳定在 367 千牛。在新聚龙煤矿采掘巷道中进行了现场应用试验，结果表明，新型缆索可确保在围岩发生大变形的情况下不断裂。吸能部件具有恒定阻力大、变形可控的优点，可有效控制深部地层中遇到的软岩大变形、硬岩岩爆等不可预测的灾害。

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引用次数: 0

Anchoring mechanical characteristics of Ductile-Expansion bolt 球墨膨胀螺栓的锚固机械特性

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

International Journal of Mining Science and Technology

Pub Date : 2024-08-01 DOI: 10.1016/j.ijmst.2024.08.005

Yu Chen , Wang Liu , Linchong Huang , Hang Lin , Yixian Wang , Yanlin Zhao , Cungang Lin

The application of ductile rock bolts has been a crucial method for solving the problems of large deformations, energy absorption and stability control issues in deep rock masses. To study the anchoring mechanism of the key expansive structure, this paper proposes a novel type of bolt — the Ductile-Expansion bolt, and conducts research on anchoring mechanics, energy absorption characteristics, and failure modes of the bolt. In addition, this paper defines the concept of load-volume ratio of metal rock bolts and proves the Ductile-Expansion bolt is capable of better improving the unit volume bearing capacity of the bolt material. Furthermore, laboratory and field tests verify the Ductile-Expansion bolt had better anchoring effect than the traditional rebar bolt, with the expansion structure favorably enhancing the ductility and energy absorption performance of the bolt. Finally, this paper microscopically analyzes the crack propagation and distribution morphology of the bolts by establishing a 3D coupled numerical model based on FDM-DEM. Numerical results illustrate the interface at the variable diameter of the Ductile-Expansion bolt serves as the transition zone between high and low stress levels. The expansion structure can impose radial compression on the medium around the bolt, which can improve the bolt anchorage performance.

韧性岩石螺栓的应用一直是解决深部岩体大变形、能量吸收和稳定性控制问题的重要方法。为了研究关键膨胀结构的锚固机理，本文提出了一种新型螺栓--延性膨胀螺栓，并对螺栓的锚固力学、吸能特性和失效模式进行了研究。此外，本文还定义了金属岩石螺栓载荷体积比的概念，并证明延性膨胀螺栓能够更好地提高螺栓材料的单位体积承载能力。此外，实验室和现场试验证明，与传统的螺纹钢螺栓相比，球墨膨胀螺栓具有更好的锚固效果，膨胀结构有利于提高螺栓的延展性和能量吸收性能。最后，本文通过建立基于 FDM-DEM 的三维耦合数值模型，对螺栓的裂纹扩展和分布形态进行了微观分析。数值结果表明，韧性膨胀螺栓可变直径处的界面是高应力和低应力之间的过渡区。膨胀结构可以对螺栓周围的介质施加径向压缩，从而改善螺栓的锚固性能。

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引用次数: 0

Mechanical properties and damage evolution characteristics of waste tire steel fiber-modified cemented paste backfill 废轮胎钢纤维改性水泥浆回填土的力学性能和损伤演变特性

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

International Journal of Mining Science and Technology

Pub Date : 2024-07-01 DOI: 10.1016/j.ijmst.2024.07.007

Shenggen Cao , Chiyuan Che , Yun Zhang , Changhao Shan , Yang Liu , Changzheng Zhao , Shuyu Du

During the process of constructional backfill mining, the cemented paste backfill (CPB) typically exhibits a high degree of brittleness and limited resistance to failure. In this study, the mechanical and damage evolution characteristics of waste tire steel fiber (WTSF)-modified CPB were studied through uniaxial compression tests, acoustic emission (AE) tests, and scanning electron microscopy (SEM). The results showed that the uniaxial compressive strength (UCS) decreased when the WTSF content was 0.5%, 1%, and 1.5%. When the WTSF content reached 1%, the UCS of the modified CPB exhibited a minimal decrease (0.37 MPa) compared to that without WTSF. When the WTSF content was 0.5%, 1%, and 1.5%, peak strain of the WTSF-modified CPB increased by 18%, 31.33%, and 81.33%, while the elastic modulus decreased by 21.31%, 26.21%, and 45.42%, respectively. The addition of WTSF enhances the activity of AE events in the modified CPB, resulting in a slower progression of the entire failure process. After the failure, the modified CPB retained a certain level of load-bearing capacity. Generally, the failure of the CPB was dominated by tensile cracks. After the addition of WTSF, a gradual increase in the proportion of tensile cracks was observed upon loading the modified CPB sample to the pore compaction stage. The three-dimensional localization of AE events showed that the WTSF-modified CPB underwent progressive damage during the loading, and the samples still showed good integrity after failure. Additionally, the response relationship between energy evolution and damage development of WTSF-modified CPB during uniaxial compression was analyzed, and the damage constitutive model of CPB samples with different WTSF contents was constructed. This study provides a theoretical basis for the enhancement of CPB modified by adding WTSF, serving as a valuable reference for the design of CPB constructional backfill.

在建筑回填采矿过程中，水泥浆回填（CPB）通常表现出高度脆性和有限的抗破坏性。本研究通过单轴压缩试验、声发射（AE）试验和扫描电子显微镜（SEM）研究了废轮胎钢纤维（WTSF）改性 CPB 的力学和损伤演变特性。结果表明，当 WTSF 含量为 0.5%、1% 和 1.5% 时，单轴抗压强度（UCS）均有所下降。当 WTSF 含量达到 1%时，改性 CPB 的单轴抗压强度与不含 WTSF 的相比降幅很小（0.37 兆帕）。当 WTSF 含量为 0.5%、1% 和 1.5% 时，WTSF 改性 CPB 的峰值应变分别增加了 18%、31.33% 和 81.33%，而弹性模量则分别降低了 21.31%、26.21% 和 45.42%。WTSF 的加入增强了改良型 CPB 中 AE 事件的活性，导致整个失效过程进展缓慢。失效后，改进型 CPB 仍保持一定的承载能力。一般来说，CPB 的破坏主要由拉伸裂缝引起。添加 WTSF 后，改性 CPB 样品加载到孔隙压实阶段时，拉伸裂纹的比例逐渐增加。AE 事件的三维定位结果表明，WTSF 改性 CPB 在加载过程中经历了渐进式损伤，而样品在失效后仍表现出良好的完整性。此外，还分析了 WTSF 改性 CPB 在单轴压缩过程中能量演化与损伤发展之间的响应关系，并构建了不同 WTSF 含量 CPB 样品的损伤构成模型。该研究为添加 WTSF 改性的 CPB 的增强提供了理论依据，为 CPB 建筑回填设计提供了有价值的参考。

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引用次数: 0

Assessment and control of the mine tremor disaster induced by the energy accumulation and dispersion of thick-hard roofs 评估和控制厚硬顶板能量积聚和分散诱发的矿震灾害

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

International Journal of Mining Science and Technology

Pub Date : 2024-07-01 DOI: 10.1016/j.ijmst.2024.07.009

Bin Yu , Mingxian Peng , Yang Tai , Shuai Guo

In order to solve the problem that current theory models cannot accurately describe thick-hard roof (THR) elastic energy and assess the mine tremor disasters, a theoretical method, a Timoshenko beam theory on Winkler foundation was adopted to establish the THR’s periodic breaking model. The superposition principle was used for this complex model to derive the calculation formulas of the elastic energy and impact load on hydraulic supports. Then, the influence of roof thickness h, cantilever length L₁, and load q on THR’s elastic energy and impact load was analyzed. And, the effect of mine tremor disasters was assessed. Finally, it is revealed that: (1) The THR’s elastic energy U exhibits power-law variations, with the fitted relationships U=0.0096L₁^3.5866, U=5943.9h^−1.935, and U=21.049q². (2) The impact load on hydraulic supports F_ZJ increases linearly with an increase in the cantilever length, thickness, and applied load. The fitted relationships are F_ZJ=1067.3L₁+6361.1, F_ZJ=125.89h+15100, and F_ZJ=10420q+3912.6. (3) Ground hydraulic fracturing and liquid explosive deep-hole blasting techniques effectively reduce the THR’s cantilever length at periodic breakages, thus eliminating mine tremor disasters.

为了解决现有理论模型无法准确描述厚硬顶板（THR）弹性能量和评估矿震灾害的问题，采用了一种理论方法，即温克勒基础上的季莫申科梁理论来建立 THR 的周期性破碎模型。针对这一复杂模型，利用叠加原理推导出了液压支架弹性能量和冲击载荷的计算公式。然后，分析了顶板厚度 h、悬臂长度 L1 和荷载 q 对 THR 弹性能和冲击荷载的影响。此外，还评估了矿震灾害的影响。结果表明(1) THR 的弹性能 U 呈幂律变化，拟合关系为 U=0.0096L13.5866，U=5943.9h-1.935，U=21.049q2。 (2) 液压支架的冲击载荷 FZJ 随悬臂长度、厚度和施加载荷的增加而线性增加。拟合关系为 FZJ=1067.3L1+6361.1，FZJ=125.89h+15100，FZJ=10420q+3912.6。(3）地面水力压裂和液体炸药深孔爆破技术有效地减少了THR在周期性断裂时的悬臂长度，从而消除了矿震灾害。

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引用次数: 0

Effect of diagenetic variation on the static and dynamic mechanical behavior of coral reef limestone 成岩变化对珊瑚礁石灰岩静态和动态力学行为的影响

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

International Journal of Mining Science and Technology

Pub Date : 2024-07-01 DOI: 10.1016/j.ijmst.2024.07.004

Linjian Ma , Jiajun Deng , Mingyang Wang , Jianping Wang , Bin Fang , Jiawen Wu

Coral reef limestone at different depositional depths and facies differ remarkably on the textural and mineralogical characteristics, owing to the complex sedimentary diagenesis. To explore the effects of pore structure and mineral composition associated with diagenetic variation on the mechanical behavior of reef limestone, a series of quasi-static and dynamic compression tests along with microscopic examinations were performed on the reef limestone at shallow and deep burial depths. It is revealed that the shallow reef limestone (SRL) is classified as a porous aragonite-type carbonate rock with high porosity (55.3±3.2)% and pore connectivity. In comparison, the deep reef limestone (DRL) is mainly composed of dense calcite-type calcium carbonate with low porosity (4.9±1.6)% and pore connectivity. The DRL strengthened and stiffened by the tight grain framework consistently displays much higher values of the dynamic compressive strength, elastic modulus, brittleness index, and specific energy absorption than those of the SRL. The gap between two types of limestone further increases with an increase in strain rate. It appears that the failure pattern of SRL is dominated by the inherent defects like weak bonding interfaces and growth lines, revealed by the intricate fracturing network and mixed failure. Likewise, although the preexisting megapores in DRL may affect the crack propagation on pore tips to a certain distance, it hardly alters the axial splitting failure of DRL under impacts. The stress wave propagation and attenuation in SRL is primarily controlled by the reflection and diffusion caused by plenty mesopores, as well as an energy dissipation in layer-wise pore collapse and adjacent grain crushing, while the stress wave in DRL is highly hinged on the insulation and diffraction induced by the isolated megapores. This process is accompanied by the energy dissipation behavior of inelastic deformation resulted from the pore-emanated microcracking.

由于复杂的沉积成因作用，不同沉积深度和沉积面的珊瑚礁灰岩在质地和矿物特征方面存在显著差异。为了探索与成岩作用变化相关的孔隙结构和矿物组成对珊瑚礁灰岩力学行为的影响，对浅埋和深埋深度的珊瑚礁灰岩进行了一系列准静态和动态压缩试验以及显微镜检查。结果表明，浅礁灰岩（SRL）属于多孔文石型碳酸盐岩，孔隙率（55.3±3.2）%，孔隙连通性高。相比之下，深礁灰岩（DRL）主要由致密的方解石型碳酸钙组成，孔隙率（4.9±1.6）%和孔隙连通性较低。由致密晶粒框架加固和加硬的 DRL 在动态抗压强度、弹性模量、脆性指数和比能量吸收方面的数值始终远高于 SRL。随着应变速率的增加，两种石灰岩之间的差距进一步拉大。从错综复杂的断裂网络和混合破坏来看，SRL 的破坏模式主要受弱结合界面和生长线等固有缺陷的影响。同样，尽管 DRL 中预先存在的巨孔可能会影响孔隙顶端一定距离的裂纹扩展，但它几乎不会改变 DRL 在冲击下的轴向劈裂破坏。SRL 中应力波的传播和衰减主要受大量介孔引起的反射和扩散以及层间孔隙塌陷和相邻晶粒破碎的能量耗散所控制，而 DRL 中的应力波则高度依赖于孤立巨孔引起的绝缘和衍射。这一过程伴随着由孔隙微裂纹引起的非弹性变形的能量耗散行为。

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引用次数: 0

Enhancing microseismic/acoustic emission source localization accuracy with an outlier-robust kernel density estimation approach 利用离群值稳健的核密度估计方法提高微地震/声发射源定位精度

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

International Journal of Mining Science and Technology

Pub Date : 2024-07-01 DOI: 10.1016/j.ijmst.2024.07.005

Jie Chen , Huiqiong Huang , Yichao Rui , Yuanyuan Pu , Sheng Zhang , Zheng Li , Wenzhong Wang

Monitoring sensors in complex engineering environments often record abnormal data, leading to significant positioning errors. To reduce the influence of abnormal arrival times, we introduce an innovative, outlier-robust localization method that integrates kernel density estimation (KDE) with damping linear correction to enhance the precision of microseismic/acoustic emission (MS/AE) source positioning. Our approach systematically addresses abnormal arrival times through a three-step process: initial location by 4-arrival combinations, elimination of outliers based on three-dimensional KDE, and refinement using a linear correction with an adaptive damping factor. We validate our method through lead-breaking experiments, demonstrating over a 23% improvement in positioning accuracy with a maximum error of 9.12 mm (relative error of 15.80%)—outperforming 4 existing methods. Simulations under various system errors, outlier scales, and ratios substantiate our method’s superior performance. Field blasting experiments also confirm the practical applicability, with an average positioning error of 11.71 m (relative error of 7.59%), compared to 23.56, 66.09, 16.95, and 28.52 m for other methods. This research is significant as it enhances the robustness of MS/AE source localization when confronted with data anomalies. It also provides a practical solution for real-world engineering and safety monitoring applications.

复杂工程环境中的监测传感器经常会记录异常数据，从而导致严重的定位误差。为了减少异常到达时间的影响，我们引入了一种创新的、可消除异常值的定位方法，该方法将核密度估计（KDE）与阻尼线性校正相结合，以提高微地震/声发射（MS/AE）源定位的精度。我们的方法通过三个步骤系统地解决异常到达时间问题：通过 4 个到达时间组合进行初始定位，基于三维 KDE 消除异常值，以及使用带有自适应阻尼系数的线性校正进行细化。我们通过突破性实验验证了我们的方法，结果表明定位精度提高了 23%，最大误差为 9.12 毫米（相对误差为 15.80%），优于 4 种现有方法。在各种系统误差、离群规模和比率下进行的模拟证实了我们方法的卓越性能。现场爆破实验也证实了该方法的实用性，其平均定位误差为 11.71 米（相对误差为 7.59%），而其他方法的误差分别为 23.56 米、66.09 米、16.95 米和 28.52 米。这项研究意义重大，因为它增强了 MS/AE 信号源定位在面对数据异常时的鲁棒性。它还为实际工程和安全监测应用提供了实用的解决方案。

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引用次数: 0

A new elastoplastic model for bolt-grouted fractured rock 螺栓灌浆破裂岩石的新弹塑性模型

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

International Journal of Mining Science and Technology

Pub Date : 2024-07-01 DOI: 10.1016/j.ijmst.2024.07.011

Haoyi Li , Shuangying Zuo , Peiyuan Lin

Complexities in mechanical behaviours of rock masses mainly stem from inherent discontinuities, which calls for advanced bolt-grouting techniques for stability enhancement. Understanding the mechanical properties of bolt-grouted fractured rock mass (BGFR) and developing accurate prediction methods are crucial to optimize the BGFR support strategies. This paper establishes a new elastoplastic (E-P) model based on the orthotropic and the Mohr-Coulomb (M-C) plastic-yielding criteria. The elastic parameters of the model were derived through a meso-mechanical analysis of composite materials mechanics (CMM). Laboratory BGFR specimens were prepared and uniaxial compression test and variable-angle shear test considering different bolt arrangements were carried out to obtain the mechanical parameters of the specimens. Results showed that the anisotropy of BGFR mainly depends on the relative volume content of each component material in a certain direction. Moreover, the mechanical parameters deduced from the theory of composite materials which consider the short fibre effect are shown to be in good agreement with those determined by laboratory experiments, and the variation rules maintained good consistency. Last, a case study of a real tunnel project is provided to highlight the effectiveness, validity and robustness of the developed E-P model in prediction of stresses and deformations.

岩体力学行为的复杂性主要源于其固有的不连续性，这就要求采用先进的栓塞灌浆技术来增强稳定性。了解栓塞灌浆断裂岩体（BGFR）的力学特性并开发精确的预测方法，对于优化 BGFR 支撑策略至关重要。本文基于正交和莫尔-库仑（M-C）塑性屈服准则，建立了一个新的弹塑性（E-P）模型。该模型的弹性参数是通过复合材料力学（CMM）的中间机械分析得出的。制备了实验室 BGFR 试样，并进行了单轴压缩试验和考虑不同螺栓布置的变角剪切试验，以获得试样的力学参数。结果表明，BGFR 的各向异性主要取决于各组成材料在某一方向上的相对体积含量。此外，从考虑短纤维效应的复合材料理论中推导出的力学参数与实验室实验测定的力学参数十分吻合，且变化规律保持良好的一致性。最后，提供了一个实际隧道项目的案例研究，以突出所开发的 E-P 模型在预测应力和变形方面的有效性、有效性和稳健性。

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引用次数: 0

Stability mechanism and control of the pumpable supports in longwall recovery room 长壁回采室可泵支架的稳定机制与控制

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

International Journal of Mining Science and Technology

Pub Date : 2024-07-01 DOI: 10.1016/j.ijmst.2024.07.006

Dong Zhang , Jianbiao Bai , Zhijun Tian , Zizheng Zhang , Yonghong Guo , Rui Wang , Ying Xu , Hao Fu , Shuai Yan , Min Deng , Shuaigang Liu

The load-bearing performance (LBP) of pumpable supports (PPS) is crucial for the stability of longwall pre-driven recovery room (PRR) surrounding rock. However, the unbalanced bearing coefficient (UBC)of the PPS (undertaking unequal load along the mining direction) has not been investigated. A mechanical model of the PRR was established, considering the main roof cantilever beam structure, to derive an assessment formula for the load, the failure criteria, and the UBC of the PPS. Subsequently, the generation mechanisms, and influencing factors of the UBC were revealed. Global sensitivity analysis shows that the main roof hanging length (l₂) and the spacing between the PPS (r) significantly impact the UBC. A novel design of the PPS and the coupling control technology were proposed and applied to reduce the UBC of the PPS in the adjacent longwall PRR. Monitor results showed no failure of the PPS at the test site, with the UBC (ζ) reduced to 1.1 consistent with the design value (1.15) basically, fully utilizing the collaborative LBP of the PPS. Finally, the maximum roof-to-floor convergence of the PRR was 234 mm, effectively controlling the stability of the surrounding rock of the PRR and ensuring the mining equipment recovery.

可抽水支架（PPS）的承载性能（LBP）对于长壁预驱动回采室（PRR）围岩的稳定性至关重要。然而，PPS 的不平衡承载系数（UBC）（沿开采方向承担不等荷载）尚未得到研究。考虑到主顶板悬臂梁结构，建立了 PRR 的力学模型，从而得出了 PPS 的荷载评估公式、失效标准和 UBC。随后，揭示了 UBC 的产生机制和影响因素。全局敏感性分析表明，主屋顶悬挂长度（l2）和 PPS 间距（r）对 UBC 有显著影响。提出并应用了新型 PPS 设计和耦合控制技术，以降低相邻长壁 PRR 中 PPS 的 UBC。监测结果表明，试验现场的 PPS 没有发生故障，UBC（ζ）降至 1.1，与设计值（1.15）基本一致，充分发挥了 PPS 的协同 LBP 作用。最后，采场顶板到地面的最大收敛为 234 毫米，有效控制了采场围岩的稳定性，确保了采矿设备的回采。

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引用次数: 0

Impact and mechanism of bisphosphonate depressant 1-hydroxypropane-1,1-diphosphonic acid on flotation decalcification of dolomite-rich magnesite ore 双磷酸盐抑制剂 1-羟基丙烷-1,1-二膦酸对富白云石菱镁矿浮选脱钙的影响和机理

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

International Journal of Mining Science and Technology

Pub Date : 2024-07-01 DOI: 10.1016/j.ijmst.2024.07.003

Wengang Liu, Xudong Chen, Wenbao Liu, Naixu Zhang, Yong Mao, Ying Guo

Given the depletion of high-quality magnesite deposits and the rising demand for high-end magnesium materials, the separation and utilization of high-calcium magnesite ores have become essential. However, the similar surface properties and solubility of semi-soluble salt-type minerals, pose significant challenges for the utilization of dolomite-rich magnesite resources. In this study, 1-hydroxypropane-1,1-diphosphonic acid (HPDP) was identified for the first time as a high-performance depressant for dolomite. Various tests, including contact angle measurements, ζ potential analysis, X-ray photoelectron spectroscopy, and atomic force microscopy, were conducted to elucidate the interfacial interaction mechanisms of HPDP on the surfaces of the two minerals at different scales. Additionally, molecular modeling calculations were used to detail the spatial matching relationship between HPDP and the crystal faces of the two minerals. It was emphasized that HPDP specifically adsorbed onto the dolomite surface by forming calcium phosphonate, ensuring that the dolomite surface remained hydrophilic and sank. Moreover, it was found that the adsorption strength of HPDP on the mineral surfaces depended on the activity of the metal sites and their spatial distribution. These findings provide a theoretical foundation for the molecular design of flotation reagents for high-calcium magnesite ores.

鉴于优质菱镁矿藏的枯竭和对高端镁材料需求的不断增长，高钙菱镁矿的分离和利用变得至关重要。然而，半溶性盐类矿物具有相似的表面性质和溶解性，这给富含白云石的菱镁矿资源的利用带来了巨大挑战。在这项研究中，1-羟基丙烷-1,1-二膦酸（HPDP）首次被确定为白云石的高性能降解剂。通过接触角测量、ζ电位分析、X 射线光电子能谱和原子力显微镜等各种测试，阐明了 HPDP 在两种矿物表面不同尺度上的界面相互作用机制。此外，还利用分子模型计算详细说明了 HPDP 与两种矿物晶面之间的空间匹配关系。研究强调，HPDP 通过形成膦酸钙特异性地吸附在白云石表面，确保白云石表面保持亲水性并下沉。此外，研究还发现 HPDP 在矿物表面的吸附强度取决于金属位点的活性及其空间分布。这些发现为高钙菱镁矿浮选试剂的分子设计提供了理论基础。

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引用次数: 0

IFC: Editorial 国际金融公司: 编辑

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

International Journal of Mining Science and Technology

Pub Date : 2024-07-01 DOI: 10.1016/S2095-2686(24)00104-6

引用次数: 0