Table of Content

15 June 2008, Volume 38 Issue 06

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Study on Rockmass Instability Based on Microseismic Monitoring Technology and Its Progress

SHI Hong, CHENG Yun-Hai, WANG Cun-Wen

2008, 38(06):  1-5. 

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The paper mainly describes the development of domestic and foreign microseismic monitoring technology in locating and engineering application，and highlights the engineering application and new advance of the microseismic technology in deep mining.It is pointed out that the key and main research points in the future microseismic monitoring technology for well interpreting and handling mining-related issues are：to develop a rapid microseismic positioning method which can satisfy the requirement of accurate locating of mine rockmass rupture，to make dynamic tracking monitoring of the three-dimensional fracture of rock stratum and coal seam in mining process，and to study the internal law of rockmass rupture field and mining stress field so as to solve the problems in forecasting mine dynamic disasters such as rock burst，coal and gas rush.The recent research achievements in these aspects are also presented.

Quality Analysis of Imported Indonesian Laterite-Nickel Ore and Trade Countermeasures

LI Yi-Xuan, YANG Li-Ming, HU Shun-Feng

2008, 38(06):  6-8+26. 

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The paper analyzes the difference between the inspection results of Rizhao Port and those of the loading port in the main quality indexes such as nickel, iron, sulfur and moisture of the imported Indonesian laterite-nickel ore in the first quarters of 2007, points out the quality problems and discusses their causes. Based on this, suggestions are made on the countermeasures including working out inspection standard, enhancing inspection supervision, carrying out technical exchange and standardizing trade contract in relation to the import trade of Indonesian laterite nickel ore.

Deformation and Destruction of Mine Workings Caused by Excavation-Induced Fault Activation

ZHAO Hai-Jun, MA Feng-Shan, LI Guo-Qing, DING De-Min, WEN You-Dao

2008, 38(06):  9-12+40. 

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Faults are the low intensity belt in rockmass and can often be activated by excavation.The experience indicates that fault activation may lead to strong deformation and destruction of mine workings.The theoretical and numerical analysis of the fault-induced deformation and destruction of mine workings shows that fault activation may augment the horizontal stress and shear stress of the shaft sidewall at the fault，and may destroy the shaft in serious case，which is different from the shaft failure caused by rock displacement without the existence of a fault.The excavation near a fault may lead to the fault activation，which is likely to cause or intensify the partial load on tunnels.When the tunnel axis is consistent with the fault strike and the vertical stress is the maximum principal stress，it is likely to lead to the tunnel rock cracking，collapse and other damages.Therefore，the research on fault activation-caused disasters can be helpful to underground engineering design，construction and safety forecasting for engineering facilities.

Method of Reducing Blasting Seismic Intensity in Gaocun Iron Mine and Its Research

LI Juan, WANG Guang-Cheng, LI Shi-Jie

2008, 38(06):  13-15+44. 

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The 2nd phase construction of Gaocun Iron Mine was started in 2005，and now the annual stripping volume has exceeded 10 million t.With the expansion and downward extension of the pit，the slope wall exposure area has increased yearly.The enclosing circle area above +30 m has complex terrain and seriously weathered rock，leading to instability of the pit slope.The pit blast-caused seism has an increasingly more serious impact on the slope and the near-pit buildings.In order to reduce the negative influence of the blast seism，nearly ten pieces of measures such as interval charge, cinder cleaning blasting, delay blasting, have been taken to reduce the blast-cause vibration based on the theoretic analysis，domestic and foreign experiences and continuous summary and exploration. In the combination of the present status, the method for vibration reduciton on its future improvement are described.

Application of Depressurized Support Technology in Chambishi Copper Mine

WANG Wen-Jie, REN Feng-Yu

2008, 38(06):  16-19. 

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In Chambishi Copper Mine in Zambia, fractured rockmass and frequent ground pressure activity seriously damaged the along-dike laneway, thus greatly affecting the safe and normal extraction of orebodies.It was concluded through the site survey and analysis that the Chambishi's mining dynamic pressure was a vertical one and concentrated on bedding and joint-developed orebodies and surrounding rock, thus leading to a great amount of caving of laneways and stopes.In view of this, the mine adopted depressurized mining and bolting support, which effectively controlled the ground pressure, improved the utilization rate of preparation engineering and smoothly realized a safe, efficient and economic extraction of orebodies.

Stability Analysis of Surrounding Rock of Underground House Group in Yantan Hydropower Station

ZHANG Zhan-Rong, SHENG Qian, LENG Xian-Lun, ZHU Ze-Qi

2008, 38(06):  20-22+30. 

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With the development of water conservancy and hydropower engineering，many underground caverns with large span and high side wall have been excavated.The stability of their surrounding rock is the key problem in the design and construction process.Based on the underground house group layout in the expansion project of Yantan Hydro-power Station and the geological conditions of their surrounding rock，a FLAC^3D numerical analysis model is established.The process of the excavation is simulated，and the distribution character of the displacement field，stress field and plastic zone after the excavation and the distribution law of the stress concentration area and the potential damage zone of surrounding rock are studied.The analysis results indicate that fault intersection and cavern crossing are the main factors influencing the surrounding rock stability，while dikes that are not intersected with the caverns have little impact.Finally，the caverns stability is evaluated comprehensively and some useful conclusions are made.

Energy Analysis of Intermittent Zonal Fracture of Roadway Wallrock

QU Tao, HAN Li-Jun, WANG De-Liang, ZHENG Tian-Xiang, ZHANG Xian-Yang

2008, 38(06):  23-26. 

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That unloading may lead to the tensile stress in rock is demonstrated by true triaxial pressure experiment.The intrinsic mechanism of energy conversion and failure process in the intermittent regional fracture process of rock is discussed.It is pointed out that the rock intermittent regional fracture is a composite result of rock energy dissipation and conservation.Energy dissipation leads to rock damage and lithologic deterioration while energy conversion is the internal cause for rock tensile fracture.The analytical formula for the radius of intermittent zonal fracture process of rock is deduced.

Analysis of Abrasion Factors of Drill Holes for Filling

LI Yao-Wu, WANG Xin-Min, ZHAO Bin, ZHANG Qin-Li

2008, 38(06):  27-30. 

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The system of drill-holes for filliong is complex and its influence factors are random and fuzzy.The main abrasion factors of drill holes for filling are analyzed and AHP quantitative method is adopted for Jinchuan Company's case.The results indicate that the slew rate is the main factor influencing the drill hole life，which has a weight of 35.3%，and the next factors are the lining quality and construction quality，with their weight being 9.8% and 9.4% respectively，hereby providing the powerful theoretical basis for the drill hole utilization and a scientific policy decision management.

Study on Properties of Crusher Station in Case of Blockage

ZHANG Ji-Wen, WANG Qing

2008, 38(06):  31-35. 

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In the semi-continuous transport ssystem of open pit mining，the blockage and queuing at the crusher station have an important effect on the integral system operation efficiency.A network model for the crusher station in case of blockage and queuing is established using the queuing network analysis method.Random simulation is used to get a set of curves describing the relation between the following indexes and the truck arrival rate，such as the queue length at the unloading platform and the length of the waiting queue，the real throughput of the crusher station，the ratio of the accumulated time of the blockage at the unloading site to the total operation time，and the ratio of the accumulated idle time to the operation time of the crusher station.The effect of the variation of the parameters in the queuing network of the crusher station on the operation characteristics of the whole system is revealed and a series of equations and curves describing the integral operation characteristics of the crusher station are obtained.The study method and results are of great application value to the best configuration of the capacity，bin volume and truck number of the crusher station.

Study on Mechanical Properties of Cracked Rockmass under Unloading

YAN Feng, JIANG Fu-Xing

2008, 38(06):  36-40. 

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Most fields of geotechnical engineering are related to the unloading process of rock and soil. It is of great theoretical and practical significance to study the mechanical properties of cracked rockmass under unloading. Based on the theory of linear elastic fracture mechanics, a generalized model for cracked rockmass was established, The research results show that fractured rockmass is unloaded along different routes, the stress intensity factor is different from the mechanical properties exhibited, and the unloading of fractured rock along the least main stress has only the property of certain stage of the unloading along the greatest main stress.

Depression Effect of Dissolved Component in Waste Saccharomyces Cerevisiae on Hematite

DAI Shu-Juan, WEI De-Zhou, DING Ya-Zhuo, WANG Yu-Juan

2008, 38(06):  41-44. 

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Starch is a commonly used hematite depressor in reverse flotation of hematite and dissolved waste Saccharomyces Cerevisiae contains a polar group similar to starch. Therefore, with single minerals of hematite and quartz as samples and sodium oleate as collector, an investigation is made on the depression effect of the dissolved phase in waste saccharomyces cerevisiae on hematite. The result shows that in single hematite system, at a pH =9, the floating rate of hematite decreases with the dosage of the dissolved component in waste saccharomyces cerevisiae until the hematite is fully depressed. In the hematite and quartz coexistence system, at a pH=11.88 and when calcium chloride is used as activator, the floating rate of hematite can be reduced to 2.47% while that of quartz can be as high as 72.5%, indicating that the dissolved component in waste saccharomyces cerevisiae is a good depressor for the separation of iron from quartz by reverse flotation.

Iron Recovery from Baosteel Rare Earth Flotation Tailings by Microwave Reduction-Magnetic Separation

LI Bao-Wei, ZHANG Bang-Wen, ZHAO Rui-Chao, LI Jie

2008, 38(06):  45-48. 

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An experimental study was conducted on the iron recovery from the tailings of BaoSteel rare-earth flotation by microwave carbothermic reduction plus magnetic separation. At a temperature below 570 ℃, more than 85% of the hematite in the tailings was reduced into magnetite . It was found that nanocarbon particles when used as the reducer can have a much greater heating rate than that of microcarbon particles , with the carbon dosage also far less than that of the latter. In the case of C=0.8% (mass fraction of nanocarbon), U=220 V (microwave reduction input voltage) and B =0.15 T (magnetic induction intensity of low intensity magnetic separation, LIMS), an iron concentrate can be obtained from the tailing with a grade of 63% and a recovery of 54.80%  by microwave reduction and one pass LIMS, with the rare-earth and niobium enriched in LIMS tailings.

Screening of A Kind of Moderate Thermoacidophilic Bacterium

SHU Rong-Bo, WEN Jian-Kang, ZHANG Yue-Hong

2008, 38(06):  49-51+55. 

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Searching for a kind of thermoacidophilic bacterium that can bear high temperature while maintaining strong iron sulfur oxidation ability is of great significance to biological metallurgy. An experimental research was therefore made on screening moderate Thermoacidophilic bacterium from the drainage of a sulfur mine in Mojiang, Yunnan. As a result, one such bacterium suitable for bioleaching of sulfide ore was isolated, which belongs to Sulfobacillus thermosulfidooxidans.It has good oxidation ability for Fe²⁺ ion or element sulfur and can bear a temperature as high as 55 ℃, with the most suitable temperature for its growth being 45 ℃; and can grow in a pH range of 0.5～3.0, with the most suitable pH for its growth being1.5～2.0. Presently, this bacterial strain is preserved in China Center for Type Culture Collection.

Effect on Bacterial Activation Conditions on Biological Pre-oxidation of Arsenic-Containing Gold Ore

YAN Ying, LIU Wen-Bin, WANG Hua-Tai, WANG Xiu-Mei, XIA Le-Xian, LIU Jian-She

2008, 38(06):  52-55. 

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To improve the activity of bacteria used for the pre-oxidation of arsenic-containing gold ore, study was made on the activation of the moderate thermophiles long domesticated by arsenic-containing gold ore and the activated bacteria was used in the biological pre-oxidation test. The result indicates that when 10 g/L FeSO₄·7H₂O and 5% gold were combined and used as energy for the bacterial activation, the arsenic removal rate of the biological pre-oxidation of gold ore can reach 75.0%, when 5% gold ore was used for the second bacterial activation, the arsenic removal rate can be further increased to 89.0%.

Research on Leaching of Manganese Oxide Slime

SHEN Hui-Ting, ZHANG Yan-Jun, LIN Xiang-Wei, ZHOU Bo

2008, 38(06):  56-61+66. 

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Tests on reduction-leaching of Daxin Mine's manganese oxide slime at acidic condition were carried out, with cheap pyrite and bagasse as the reductant respectively. The results show that in proper technical conditions, both methods can obtain a manganese leaching rate higher than 95%. Manganese sulfate and manganese carbonate were prepared by purifying the two pregnant solutions from the above leaching tests, with both satisfying the requirements for qualified industrial products. The study on the leaching kinetics of both processes indicates that the pyrite leaching process is controlled by the chemical reaction on the particle surface; and the bagasse hydrolysis leaching process is controlled jointly by chemical reaction and diffusion in the early period and by diffusion in the late period.

Oxidation Mechanism of Vanadium Extraction in Stone Coal Roasting with Cyclic Oxidation

CHEN Tie-Jun, QIU Guan-Zhou, ZHU De-Qing

2008, 38(06):  62-66. 

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Vanadium-containing stone coal is an important vanadium resource in China and oxidized roasting is the foundation for extracting vanadium from stone coal. With a vanadium-containing stone coal from Hu Bei Province as the research target, potentiometric titration, X diffraction, energy spectrum and electron probe are taken to study the change in valence, occurrence and phase transition of vanadium during oxidized roasting process. On this basis, oxidation kinetics of vanadium is studied. The result shows that vanadium in the stone coal mainly occurs in illite; the phase transition in roasting process results in the disappearance of vanadium-containing illite and the formation of soluble vanadate and orthoclase-albite; vanadium oxidation is a staged process(V(Ⅲ)→V(Ⅳ)→V(Ⅴ)); and that its oxidation reaction is controlled by diffusion kinetics whose dynamic apparent activation energy is E =81.19 kJ/mol.

Study on Enhancing Desulfurizing Flotation of Fine Coal by Sonoelectrochemical Process

ZHANG Hong-Xi, DONG Xian-Shu, WANG Zhi-Zhong

2008, 38(06):  67-68+104. 

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The technology of flotation enhanced by sonoelectrochemical process was used in the desulfuration test on Shanxi Gujiaotun fine coal. With calcium hydroxide as the electrolyte and ethanol as the additive, the effect of ethanol dosage, treatment time, electrolytic current and ultrasonic power on desulfuration rate was investigated. The desulfuration results were compared with those of electrochemically enhanced flotation and ultrasonically enhanced flotation. The results show that, at an ethanol dosage of 30 mL, treatment time of 20 min, electrolytic current of 1.5 A and ultrasonic power of 250 W, this process can achieve a desulfuration rate and clean coal yield of 75.42% and 72.15% respectively , better than those by other two methods.

Flocculant Types and Its Application in Tailings Settlment

ZHANG Qu-Fei

2008, 38(06):  69-72. 

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Flocculant types and its applications in tailings settlement are described. Its development trend is analyzed and it is pointed out that popularization of tailings settlement by flocculation to realize a high concentration tailing transport and improve the water recycling rate is the development orientation of the tailings handling in China's concentrators.

Study on Mineralogical Characteristics of High Stress Soft Rock at Depth of Nanshan Mine

ZHOU Li, HE Man-Chao

2008, 38(06):  73-76. 

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To determine the deformation mechanical mechanism of roadways in high-stress soft rock at depth in Hegang Nanshan Mine and the roadway support measures, study was made on the mineralogical characteristics of the rock by X-ray diffraction, X-ray energy spectrum analysis and scanning electronic microscope. The results indicate that the rock has developed fissures and contains mainly quartz, feldspar and clay minerals. The feldspatite has leaching alteration phenomenon. The clay is mainly composed of illite /smectite interstratified layer that mainly contains smectite. The monocrystals in the mixed layer are mainly in filamentous, lath-like, feathery and wavelike sheet shapes, and the crystal aggregates are honeycomb-like, network-like, granular, flexuous and hair-shaped. The clay minerals occur in inter-granular pores mainly in bridge, scattered and film-like shapes.

Zircon U-Pb Dating of Sabei Tin Deposits and Its Geological Implications

LIN Jin-Fu, WEI Long-Ming, YU Heng-Xiang

2008, 38(06):  77-79+90. 

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Sabei tin deposits in the eastern Zunghar in Xinjiang occur in the quartz veins of biotite granites and also alkali amphibole-bearing quartz veins of alkali-enriched granites，whose distribution is generally controlled by the NNE- and NE- trending faults in the area.The quartz veins and their mineralization are closely related with the lithological variations in granites in Kalamaili ore deposits zone.The lithology evolves from calc-alkaline，via near-alkali granites，to alkali granites from (N)NW to (S)SE，along with the quartz veins varying from quartz-dominated，via cassiterite-bearing quartz-dominated，to cassiterite-bearing amphibole quartz-dominated.SHRIMP U-Pb zircon dating indicates that the age of the zircon in cassiterite-quartz is （329.2±1.5） Ma，close to the formation time of the Laoyaquan-Hongtujing-Sujiquan biotite granitic batholith; and the age of the zircon in alkaline-enriched granites is （313±2） Ma~（314±5） Ma，in conformity with the active period of post-collisional plutonic rocks (330~310 Ma) in the eastern Junggar.Therefore，the ages of diagenesis and mineralization of Sabei tin deposits correspond respectively to the first (340~330 Ma) and second (300~285 Ma) of the three peak phases of the post-collisional mineralization in the northern Xinjiang Province.This ore formation is of multi-phase type and is not only related to alkali granites but also to biotite granites.

Design of Ground Pressure Monitoring System

XIAO Qing, WU Su-Ying

2008, 38(06):  80-81. 

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The application of underground pressure testing technology is analyzed and evaluated.It is proposed to establish a  microseismic monitoring system in mines adopting ARM embedded system and the conventional ground pressure system，and to use uninterrupted data information collection，three dimensional background analysis and networking technology transmission to realize a real time monitoring and forecastf deep ground pressure activity so as to timely and reliably guide the mine safety production.

Study on Geochemical Characteristics of Yelingtou Orefield in Zhejiang

QIAN Jian-Min, ZHONG Zeng-Qiu, LOU Xin-Tao, ZHENG Gen-Jin

2008, 38(06):  82-84+93. 

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Yelingtou orefield is in Shaoxing-southeast of Longquan gold，silver，copper，lead，zinc and molybdenum metallogenic belt.There have long been different views about the genesis as metamorphic hydrothermal solution，volcanic thermal，metamorphic hydrothermal solution superposed by volcanic activity，or depositing-reworking types，and there is a rather identical view that copper，lead，zinc and molybdenum metallogeny is related to volcanic activity.The largest gold deposit in Zhejiang in the orefield-Suichang Gold Mine is now a crisis mine，where the exploration work for alternative resource for the crisis mine is being carried out.Through the comparative study on the geochemical data including the rare earths，lead isotope，stable isotope and isotope chronology of the different deposits and geological bodies in the ore field，it is made clear that the metallogeny of Yelingtou orefield was during  82.5～164 Ma，gold-silver deposits were formed during the volcanic activity of Yanshan Period，and the ore-forming is closely related to the multi-stage medium acidic volcanic activity in Yanshan Period.The major points in the exploration and study for alternative resource should be those structures and geological bodies related to volcanic activity.

Realization of Automatic Attribute Setting of Houses in CAD DLG

LIU De-儿, XIAO Hai-Ping

2008, 38(06):  85-86+141. 

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The constituent attribute configuration of DIG is an important and hard work in converting DIG data to GIS data，with the house attribute configuration being the principal part.Based on the spatial relation between a house polygon and its attributes and through the study and analysis of the available algorithms for judging a point in or outside the polygon，the ray method was adopted as the basic algorithm which was exceptionally treated.The automatic setting of the house attributes in DIG was realized by using this algorithm and a series of tests were also made on this algorithm.The algorithm was proven to be stable and reliable.

Industrial Test of SCTφ4.5 m Magnetic Dewatering Tank

GAO Zhi-Zhe, LI Biao, WU Wen-Hong, CAI Hai-Hui

2008, 38(06):  87-90. 

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SCTφ4.5 m magnetic dewatering tank adopts multi-level ring type magnet system to produce a more rational magnetic field, better facilitating the magnetic agglomeration of magnetic minerals so as to improve the recovery of magnetic minerals. The number of the magnet ring levels of the system can be adjusted to satisfy the need of upsizing design. The industrial test result in Dagushan Concentrator in Mining Co. AnSteel Group indicates that the dry ore throughput of this machine is 2.33 times that of the currently used φ3 m conventional one. At a similar feed, the performances of SCTφ4.5 m magnetic dewatering tank such as concentrate grade, tailing grade and magnetic iron loss are better than those of the latter and what's more, it is more adaptable to the feed condition change. Therefore, it is of good popularization value.

R & D and Application of Geological，Measurement and  Mining System Software for Mengku Iron Mine

LI Jiao-Qun, LI Xu-Dong

2008, 38(06):  91-93. 

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Taking Mengku Iron Mine of Xinjiang Bayi Iron & Steel Co.as a specific case，and in combination with the development of ASAD application technology，the paper describes the conception of the compilation of geological，measurement and mining system software for open pit mines and the key techniques for its realization.It is summarized that mine digitalization development is a process that involves many aspects such technology，personnel and mine management，which are all embodied in the personalized characteristics of the system software.This system software has been developed and applied for many years and is being continuously improved and updated so as to fully satisfy the requirement of mine personalization and to better serve the auxiliary design and management of open pit mining production.

Rendering of Vector Data over 3D Scene

LIU Zhao-Hua, YANG Jing-Yu, DAI Chen-Guang

2008, 38(06):  94-96+153. 

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A method of rendering vector data over 3D terrain based on stencil shadow volume algorithm is presented，which can realize a high quality real-time overlay of vector data on three-dimensional scene.Since this is a screen-space algorithm，it is per-pixel exact and does not suffer from aliasing artifacts as texture-based conventional techniques.Besides，it is not restricted by the underlying terrain geometry and its implementation efficiency is independent of the complexity of the terrain data but only depends on the complexity of the vector data.The key techniques of the rendering of vector data over 3D terrain based on stencil shadow volume algorithm are detailed and the effectiveness of this method is test-proven.

Application of SLon Magnetic Separators in Diaojuntai Concentrator Before and After Its Process Transformation

ZHU Ge-Lai, ZHANG Guo-Qing, TANG Wen-Bin, XIONG Da-He, ZHANG Chun-Hao

2008, 38(06):  97-99. 

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Diaojuntai Concentrator used 15 SLon-2000 high intensity magnetic separators to replace the Shp-3200 flat-ring high intensity magnetic separators in its original process composed of continuous grinding-low intensity magnetic separation, high intensity separation and reverse flotation. After the technical transformation, the process consisting of staged grinding, coarse and fine size-classified separation by gravity separation, magnetic separation and anionic reverse flotation uses 15 SLon-2000 high intensity magnetic separators and 15 SLon-2000 medium intensity magnetic separators for tailing discarding by desliming and at coarse size respectively. These SLon magnetic separators have played an important role in reducing fine metal loss, improve metal recovery, creating a good condition for reverse flotation and reducing middling regrinding load, thereby providing guarantee for the a continuous achievement of excellent production performance of Diaojuntai Concentrator.

Energy Efficient Operation of AC Asynchronous Motor by Soft Starter

HOU Shu-Ping, YU Bai

2008, 38(06):  100-104. 

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Through the analysis of the working principle of asynchronous motor's soft-starter, a hardware expansion of the soft-starter was made based on single-chip microcomputer Intel-89C51 to realize the set up and alteration of the motor operation parameters. By means of a close-circuit feedback system composed of a power factor measuring circuit and a soft-starter's thyristor voltage modulator, the single-chip microcomputer can make corresponding adjustment of the output voltage of the soft-starter according to the load change, enabling the motor to keep running at the set power factor so as to realize a constant power factor control of AC asynchronous motor and gain the goal of energy-efficient running.

Study on New Methods for Identifying Tunnel Layer Relationship in Mine Ventilation Simulation System

WEI Lian-Jiang, HAO Xian-Jie, ZHANG Hong-Jie, SHEN Long

2008, 38(06):  105-107. 

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To correctly identify the spatial layer relationship of single line tunnels，based on the in-depth study of the tunnel connection relation of the ventilation network，“auto-bridging” and “virtual double-line” methods for identifying the spatial layer relationship of single line tunnels are put forward for the first time.The “virtual double-line” method can render the ventilation system the double-line graphics of fixed width rapidly and automatically without calculating the coordinates of the double-line points，on which the tridimensional graphics of the ventilation system can be created rapidly and automatically for better identifying the relation between layers of tunnels.These two methods have the advantages of small calculation and high efficiency，and have removed the defects in conventional ones.

Simulation Study on Influence of Environmental Factors on Release of  Heavy Metal Ions out of Sulfide Ore Tailings

LIN Mei-Qun, MA Shao-Jian, WANG Gui-Fang, LIU Ping, SU Xiu-Juan, QIN Xiang-Min

2008, 38(06):  108-111+115. 

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The influence of the environmental factors on the release of Cu²⁺，Zn²⁺，Pb²⁺，Cr³⁺ out of the tailings of a copper sulfide mine was investigated by static soaking experimental method through altering the temperature of the soaking system, upper layer solution and ore sample layer height and ore layer cross-section and blowing air into the solution surface and adding flotation agent to the system. It is deduced from the test results that, in terms of heavy metal ion release, the environmental danger from the sulfide ore tailing reservoirs in North China could be more serious than that in South China, and that in summer more serious than in winter. The larger the accumulated water depth or area covering the tailings in the reservoir, the easier the heavy metal ions will be released; the thicker the tailing deposited in the reservoir, the easier Zn²⁺ will be released while the more difficult Pb²⁺, Cu²⁺ and Cr³⁺ will be released. The great disturbance to the water surface of the tailing reservoir may enhance the release of heavy metal ions and the flotation reagent will also affect their release but the conditions are rather complex.

Fuzzy Fault Tree Analysis of Failure of Water Supply Network for Mine Dust-proofing

HOU Xiao-Dong, JIANG Zhong-An

2008, 38(06):  112-115. 

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Mine dustproof water supply network is a main underground dustproof facility and its operational reliability directly influences the dusting result. The paper analyzes the main factors that can lead to the dustproof network failures and establishes the fault tree correspondingly. Through qualitative analyses, 31 minimal cut sets are obtained. Expert judgment method and fuzzy sets theory are used in combination to assess the fuzziness of base events of the fault tree. Taking as example a base event of “starting water hammer”, its fuzzy failure value rate is calculated to be 0.001 2. The failure rates of various factors are compared and it is found that the main factors leading to the network failures are in turn third-party interference, chemical erosion, impurities blockage and accessory equipment failure.

Evaluation of the Steep Slope Stability in Surface Mine Based on Theory of GPS And Regression Analysis

LI Yan, WANG Run-Sheng, LIU Zhi-Zhong

2008, 38(06):  116-118. 

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With the opencast working，Surface Mine is full of danger because of rock slope.In this paper，the monitoring system configuration and data processing are discussed in combination with GPS monitoring of slope deformation in an Iron Mine.In order to seize the rule of rock Stability and provid a more reliable basis for taking measures for control the rock Stability，the dynamic monitoring system and rock Stability evaluation method are developed.The rock Stability in the surface mine is resolved so as to control the steep slope,which can hepe to the development of the Surface Mine.

Dynamic Deformation Comprehensive Monitoring Technology and Stability Forecase for Mine Slope

WU Yong-Bo, GAO Qian, WANG Yan-Ming

2008, 38(06):  119-122. 

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In light of the engineering geological condistion，shape，stability and measurement target for Changba open-pit slope，a dynamic comprehensive deformation monitoring scheme based mainly on GPS technology was proposed.596 d first stage of deformation monitoring was made during Dec.3 2001 and Aug.13，2003; and in light of the potential slip body of 1500m bench at north wall disclosed in the first stage monitoring，210 d second stage deformation comprehensive monitoring was carried out during May 1,2006 and Nov.30，2006.Through the deformation monitoring and in combination with theorectical analysis and numerical simulation，the stability of the east wall was forecasted，laying a foundation for the mine safety production.

Application of Quantitative Evaluation Model in Mine Safety Evaluation

LI Hua, LI Hai-Liang, WANG Xiang-Gui

2008, 38(06):  123-125. 

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The index quantification and the determination of the weight of sub-units in mine safety evaluation was preliminarily studied.Fuzzy theory and probability value determination method for quantifying the basic indexes，the primary and secondary index queuing，expert consultation and link-relative method for determining the weight of sub-units and the fuzzy theory were used in the safety evaluation of the blasting system of Anhui Dachang Iron Mine.It was concluded that the blasting system was of safety rating.

Forecast Method of Water In-Rush of Floor over Confined Water Body and Its Prevention and Control Measures

HUANG He, LI Chong

2008, 38(06):  126-129. 

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Water in-rush of coal floor is a complex geological and mining-affected phenomenon，which refers to the natural disaster that the confined water under the coal seam breaks through the blockage of the floor isolation and comes into the mined-out area of working face in a rush，relax or delayed manner，leading to the increase of water inflow or even submerge the mine.Therefore，it is very necessary to study the forecast method of floor water in-rush and its prevention and control measures.In light of the occurrence characteristics of No.6 coal seam in Zhuzhuang Coal Mine of Huaibei Mining Group，and based on large amount of site measurement and theoretical analysis，the forecast method of water in-rush of floor in mining over confined water body and its prevention and control measures were proposed，and the water prevention and control plan was determined，ensuring the safe mining of No.6 coal seam over confined water body.

Effect of Ca/Si Ratio of Red Mud-Based Cementing Material on Na+ Solidification Performance

SUN Wen-Biao, FENG Xiang-Peng, YI Zhong-Lai

2008, 38(06):  130-137+144. 

Asbtract ( 1790 )  

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The hydration process of red mud-based cementing material is studied by NMR and IR means and by structural analysis method. The effect of Ca/Si ratio of red mud cementing material on the solidification performance of Na+ of hydration product is disclosed. The results show that with the decrease of Ca/Si Ratio, along with the substitution of Al for Si, the structural unit polymerization degree of ［Si(Al)O₄］increases and ［SiO₄］and ［AlO₄］tetrahedra increase. Consequently, the C-S-H gel where Si occurs in Q¹ and Q² forms turns into (Na, Al)-C-S-H gel with SiQ² , SiQ³ and SiQ⁴ structural units, benefiting the solidification of Na+ in forms of chemical adsorption and chemical sosoloid.

Test on Synthesizing Zeolite with Fly Ash of Lueyang Power Plant

TAN Hong-Bin

2008, 38(06):  138-141. 

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Test was conducted on synthesizing zeolite A and zeolite Y by hydrothermal method and melting-hydrothermal method with the fly ash of Lueyang Power Plant. The results indicate that when fly ash is under the hydrothermal reaction and alkaline condition at 80 ℃ for 4 d, fly ash zeolite containing zeolite A and zeolite Y can be obtained. Zeolite A can be obtained by adding Al(OH)₃ and NaOH solids into fly ash, melting at 800 ℃ for one hour and hydrothermal reaction at 80 ℃for 12 h; and Zeolite Y can be obtained by adding wollastonite and NaOH solids into the fly ash, melting at 800 ℃ for one hour and hydrothermal reaction at 80 ℃ for 36 h. The three kinds of synthesizing zeolite are compared with natural zeolite and fly ash in adsorbing Cd²⁺ in the solution, and the adsorption ability is sequenced from strong to weak as: zeolite Y ＞zeolite A ＞flyash zeolite ＞natural zeolite ＞fly ash.

Tellurium Recovery from General Slag of Copper Anode Sludge

JIANG Guo-Min

2008, 38(06):  142-144. 

Asbtract ( 2006 )  

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The general slag produced in treating the anode sludge of copper electrolysis in a copper smelter has a high tellurium content and test is made on recovering the tellurium from the slag by leaching. The results indicate that satisfactory tellurium leaching rate can not be obtained by conventional acid leaching processes. An oxidizing acid leaching process with sulfuric acid as lixiviant and KMnO₄ as oxidant can obtain a tellurium leaching rate of 90.09% at a leaching temperature of 80 ℃, liquid to solid ratio of 5∶1, KMnO₄ dosage of 0.008 g/g (of raw material), sulfuric acid concentration of 3.6 mol/L and leaching time of 5 h. Meanwhile, 97.81% copper in the slag can also be leached out and further extraction of tellurium and copper can also be made from the leaching solution.

Progress in Comprehensive Utilization of Meishan Concentrator's Fine Tailings

DU Jian-Fa

2008, 38(06):  145-147+149. 

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The concentrator of Meishan Mining Co. produces annually about 0.85 million t fine tailings and the existing tailings reservoir capacity will sustain six years' production. It has become an urgent issue to realize a comprehensive utilization of the fine-sized tailings. Therefore, Meishan Mining Co. has carried out in recent years a great deal of work in this respect and has achieved certain progress, including enhancing the thickening-dewatering of the fine-sized tailing, reducing its metal loss and researching and developing new building materials with the fine-sized tailings as the raw material.