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Optimization of monitoring the stability of surrounding rock in a metal mine

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 359-367页

作者： Bo Song Min Zhong Xin Dong Pei-fu Wang school of civil and environmental engineering University of Science and Technology Beijing Beijing 100083 China Zhaojin mining Industry Limited Company Shandong 265400 China

Through analyzing the failure mechanics of rock under blasting effect, the optical fiber sensing system was used to monitor the strain of surrounding rock under blasting effect. Combined with practical exploration, the stability of surrounding rock was computed by numerical simulation using the blasting wave obtained from the site. According to the change regularities of displacement, stress, acceleration, and velocity of tunnels before and after explosion, the layout of key monitoring points was optimized. When disposed the monitoring position of sensors, the regular points should be considered to use as key points and the periodical monitor should be a part of the long-term monitor. In practical application, considering the geology condition in site, monitor points should be added on the area with joints and faults to assure the integrity of monitor data and the preciseness of decision.

关键词： metal mine monitoring optical fiber sensor numerical simulation blasting vibration

Waste activated sludge hydrolysis and acidification： A comparison between sodium hydroxide and steel slag addition

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Journal of environmental Sciences 2016年第10期28卷 200-208页

作者： Ying Zhang Chaojie Zhang Xuan Zhang Leiyu Feng Yongmei Li Qi Zhou State Key Laboratory of Pollution Control and Resources Reuse School of Environmental Science and Engineering Tongji University Shanghai 200092 China school of civil Mining and Environmental Engineering Faculty of Engineering and Information Sciences University of Wollongong NSW 2522 Australia East China Electric Power Design Institute Co. Ltd. of China Power engineering Consulting Group Shanghai 200063 China

Alkaline treatment with steel slag and NaOH addition were investigated under different pH conditions for the fermentation of waste activated sludge. Better performance was achieved in steel slag addition scenarios for both sludge hydrolysis and acidification. More solubilization of organic matters and much production of higher VFA （volatile fatty acid） in a shorter time can be achieved at pH 10 when adjusted by steel slag. Higher enzyme activities were also observed in steel slag addition scenarios under the same pH conditions. Phosphorus concentration in the supematant increased with fermentation time and pH in NaOH addition scenarios, while in contrast most phosphorus was released and captured by steel slag simultaneously in steel slag addition scenarios. These results suggest that steel slag can be used as a substitute for NaOH in sludge alkaline treatment.

关键词： Waste activated sludgeAlkaline treatmentSteel slagSodium hydroxide

Treatment of bauxite residue dust pollution by improving structural stability via application of synthetic and natural polymers

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Journal of Central South university 2019年第2期26卷 440-448页

作者： DING Xu-han XU Guang ZHOU Wei GUO Xing-yun Department of mining engineering and Metallurgical engineering Western Australian School of MinesCurtin University State Key Laboratory of Coal Resources and Safe mining China University of Mining and Technology Sustainable engineering Group School of Civil and Mechanical Engineering Curtin University

The residue drying area(RDA)is the major source of fugitive red sand(RS)dust emissions in the bauxite mining industry and causes serious environmental and safety *** stabilizer(PS)is one of the promising non-traditional stabilizers to mitigate such *** research investigated the unconfined compressive strength(UCS)of RS using synthetic polymer stabilizer(SPS)and natural polymer stabilizer(NPS),and to determine the optimum application concentration and mixing ratio of the PAM and Guar gum *** illustrated that PAM apparently outperform Guar gum in stabilizing sand *** mixture of PAM and Guar gum is more effective than individual *** optimum polymer concentration and the mixing ratio are 0.94 wt.%and 0.6(PAM:total(PAM+Guar gum)),respectively.A rigorous regression model was developed to predict the UCS value based on application concentration and mixing ratio for the purpose of cost and time efficiency.

关键词： unconfined compressive strength experimental design polyacrylamide Guar gum combined application

Mechanical Response and Energy Dissipation Analysis of Heat-Treated Granite Under Repeated Impact Loading

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Computers, Materials & Continua 2019年第4期59卷 275-296页

作者： Zhiliang Wang Nuocheng Tian Jianguo Wang Shengqi Yang Guang Liu school of civil and Hydraulic engineering Hefei University of TechnologyHefei230009China school of Resource and environmental engineering Hefei University of TechnologyHefei230009China school of Mechanics and civil engineering China University of Mining and TechnologyXuzhou221116China

The mechanical behaviors and energy dissipation characteristics of heat-treated granite were investigated under repeated impact *** granite samples were firstly heat-treated at the temperature of 20℃,200℃,400℃,and 600℃,*** thermal damage characteristics of these samples were then observed and measured before impact *** impact compression tests finally were carried out using a modified split-Hopkinson pressure bar under three impact velocities of 12 m/s,15 m/s,and 18 m/*** test results show that the mineral composition and the main oxides of the granite do not change with these treatment *** number of microcracks and microvoids decreases in the sample after 200℃ *** mechanical properties of a sample after 600℃ treatment were rapidly deteriorated under the same impact *** average of peak stress is much smaller than those after 20℃,200℃ and 400℃ *** heat-treated samples have an energy threshold *** the dissipated energy of a sample under a single impact is less than this threshold,the repeated impacts hardly lead to further damage accumulation even if its total breakage energy dissipation(BED)density is *** the same number of repeated impacts,the cumulative BED density of a sample after 600℃ treatment is the largest and its damage evolves most *** total BED density of the sample after 200℃ treatment is the highest,which implies that this sample has better resistance to repeated impact,thus having less crack initiation and growth.

关键词： Granite heat treatment repeated impact dynamic response energy dissipation

Mechanical behavior of micaceous clays

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Journal of Rock Mechanics and Geotechnical engineering 2019年第5期11卷 1044-1054页

作者： Jiahe Zhang Amin Soltani An Deng Mark B.Jaksa school of civil Environmental and Mining EngineeringThe University of AdelaideAdelaideSA 5005Australia Department of Infrastructure engineering The University of MelbourneParkvilleVIC 3010Australia

This study aims to investigate the effect of mica content on the mechanical properties of *** available ground mica was blended with a locally available clayey soil,at varying mica contents by mass of 5%,10%,15%,20%,25%and 30%,to artificially prepare various micaceous clay *** preliminary testing phase included consistency limits and standard Proctor compaction *** primary testing program consisted of unconfined compression(UC),direct shear(DS)and scanning electron microscopy(SEM)*** test results showed that the liquid and plastic limits exhibited a linear,monotonically increasing trend with increase in mica *** rate of increase in the plastic limit,however,was found to be greater than that of the liquid limit,thereby leading to a gradual transition towards a non-plastic,cohesionless *** soft,spongy fabric and high water demand of the mica mineral led to higher optimum water contents and lower maximum dry unit weights with increasing mica *** low confinement conditions,*** UC test and the DS test at low normal stresses,the shear strength was adversely affected by ***,the closer packing of the clay and mica components in the matrix under high confinement conditions offsets the adverse effects of mica by inducing frictional resistance at the shearing interface,thus leading to improved strength resistance.

关键词： Micaceous clay Mica content Consistency limits Compaction Shear strength Confinement Frictional resistance

Influence of towing speed on effectiveness of rolling dynamic compaction

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Journal of Rock Mechanics and Geotechnical engineering 2020年第1期12卷 126-134页

作者： Brendan T.Scott Mark B.Jaksa Peter W.Mitchell school of civil Environmental and Mining EngineeringThe University of AdelaideSouth Australia5005Australia Aurecon AdelaideSouth Australia5000Australia

The influence of towing speed on the effectiveness of the 4-sided impact roller using earth pressure cells(EPCs)is *** field trials were undertaken;the first trial used three EPCs placed at varying depths between 0.5 m and 1.5 m with towing speeds of 9-12 km/*** second used three EPCs placed at a uniform depth of 0.8 m,with towing speeds of 5-15 km/*** findings from the two trials confirmed that towing speed influences the pressure imparted to the ground and hence compactive *** paper proposes that the energy imparted to the ground is best described in terms of work done,which is the sum of the change in both potential and kinetic *** practice of using either kinetic energy or gravitational potential energy should be avoided as neither can accurately quantify rolling dynamic compaction(RDC)when towing speed is varied.

关键词： Rolling dynamic compaction(RDC) Optimum towing speed Ground improvement

Solvent extraction of rare earth ions from nitrate media with new extractant di-(2,3-dimethylbutyl)-phosphinic acid

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Journal of Rare Earths 2016年第7期34卷 724-730页

作者：王俊莲陈广徐盛明尹祉力张覃 civil and environmental engineering school University of Science and Technology Beijing Institute of Nuclear and New Energy Technology Tsinghua University mining College Guizhou University College of Chemistry and Chemical engineering Shihezi University

As a relatively new extractant, di-（2,3-dimethylbutyl）-phosphinic acid （HYY-2） is more efficient to separate heavy rare earths Tm/Yb/Lu than Cyanex 272 and P507. In this paper, HYY-2 was synthesized in our lab, and the extraction equilibrium, thermodynamics and stripping acidity for La, Gd and Y, which stood for light rare earth elements （REE）, middle REE and heavy REE respectively, from nitrate media with this extractant were investigated. Meanwhile, extraction ability, capacity and stripping acidity of HYY-2 were investigated and compared with those of Cyanex 272 and P507. The separation performance for rare earth element couples Gd/Eu and Er/Y were also studied. Compared to Cyanex 272, it possessed higher extraction capacity; while compared with P507, it has lower stripping acidity. The maximum βGD/Eu 1.46 occurred at PHequilibrium=2.78 and the maximumβEr/Y was 1.47 when pHequilibrium= 2.01.

关键词： di-(2,3-dimethylbutyl)-phosphinic acid rare earth element solvent extraction separation

Measurement and study of the distributing law of in-situ stresses in rock mass at great depth

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Journal of university of Science and Technology Beijing 2006年第3期13卷 207-212页

作者： Zhuoying Tan Meifeng Cai State Key Laboratory for High-Efficient mining and Safety of Metal Mines Civil and Environmental Engineering School University of Science and Technology Beijing Beijing 100083 China

To solve the technical cruxes of the conventional system in deep rock mass, an automatic testing system for hydraulic fracturing that includes a single tube for hydraulic loop, a pressure-relief valve, central-tubeless packers, and a multichannel real-time data acquisition system was used for in-situ stresses measurement at great depths （over 1000 m） in a coalfield in Juye of Northern China. The values and orientations of horizontal principal stresses were determined by the new system. The virgin stress field and its distributing law were decided by the linear regression from the logged 37 points in seven boreholes. Besides, the typical boreholes arranged in both the adjacent zone and far away zone of the faults were analyzed, respectively. The results show that a stress concentration phenomenon and a deflection in the orientation of the maximal horizontal stress exist in the adjacent zone of the faults, which further provides theoretical basis for design and optimization of mining.

关键词： rock mass at great depth earth stress hydraulic fracturing in-situ stress distribution

The beneficiation of tailing of coal preparation plant by heavymedium cyclone

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International Journal of Coal Science & Technology 2018年第3期5卷 374-384页

作者： Ataallah Bahrami Yousef Ghorbani Mirsaleh Mirmohammadi Behnam Sheykhi Fatemeh Kazemi Department of mining engineering Urmia UniversityUrmia Iran Department of civil Environmental & Natural Resources Engineering Lulea University of Technology Lulea Sweden school of mining engineering University of Tehran TehranIran

Dense-medium cyclones have been used for beneficiation of fine particles of coal. In this study, the usability of cyclones in the beneficiation of tailings of a coal preparation plant was investigated. For this purpose, separation tests were conducted using spiral concentrator and heavy medium cyclones with the specific weight of medium 1.3-1.8 （g/cm^3） on different grading fractions of tailing in an industrial scale （the weight of tail sample was five tons）. Spiral concentrator was utilized to beneficiate particles smaller than 1 mm. In order to evaluate the efficiency of cyclones, sink and float experiments using a specific weight of 1.3, 1.5, 1.7 and 1.9 g/cm^3, were conducted on a pilot scale. Based on the obtained results, the recovery of floated materials in cyclones with the specific weight of 1.40, 1.47 and 1.55 g/cm^3 are 17.75%, 33.80%, and 50%, respectively. Also, the cut point （Pso）, which is the relative density at which particles report equally to the both products are 1.40, 1.67 and 1.86 g/cm^3. The probable errors of separation for defined specific weights for cyclones are 0.080, 0.085 and 0.030, respectively. Also, the coefficients of variation was calculated to be 0.20, 0.12 and 0.03. Finally, it could be said that the performance of a cyclone with a heavy medium of 1.40 g/cm^3 specific weight is desirable compared with other specific weights.

关键词： Heavy media cyclones Coal Tailings Coal preparation plant Tromp curve