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By Min-Yuan Cheng

Landslides not only cause interruption of road traffic but also cause damage to passing by vehicles and injure people in Taiwan. Due to the budget limitation of government, the overall assessments and maintenance of all road slops cannot be fulfilled. Priority of road for maintenance is a crucial task for road maintenance department to identify. The purposes of this research are to develop an assessment method for the landslide risk and to make strategies to maintain or repair the slopes along mountain roads. To aim both needs to take into account the environmental conditions of the slopes, the engineering measures for stabilizing road slopes, the transportation issues, and the human concerns when dealing with the slopes maintenance along the mountain roads. This study firstly establishes the Landslides Damage Risk Evaluation Model (LDREM) to calculate the risk of slope failure, considering the probability of landslides, temporal probability, spatial impact probability, the value of human life, transportation time increased, and travel cost due to detour etc., and then the loss of life and transportation can be calculated. Secondly, based on the value of risk and the risk evaluation, considering the risk acceptance criteria for loss of life could provide assistance for road maintenance department to determine the priority of mountain roads for maintenance.

Aug 1, 2013

By T. Fliß

The protection of natural resources is of essential importance in times of rapidly increasing populations and resulting shortage of agricultural land. Soil and groundwater resources play a central role for the production of food or feed of any kind. The intensive agricultural and environmentally friendly use of these resources must ensure sufficient income and sustainability of life for future generations. Mining projects often represent a particularly deep intervention into ecosystems due to their size as well as the most expensive treatment processes. Conventional mines comprising of shafts and developed mining fields require the stockpiling of waste rock and in particular to potash mining, the discharge of brines from raw salt processing. In contrast, mining operations based on the solution mining method can be operated without major environmental impacts and lower security risks. While the solution mining for the production of rock salt finds application since more than 500 years, exist a procedure to produce potash using solution mining only since the 1980's. For solution mining drill holes are used to exploit the potash, launched from the surface into the deposit. The exploitation of the raw material occurs by the dissolution of the potash injecting solvents and creating so-called brine caverns. Currently, a number of mining projects in Carnallite deposits by the solution mining method are in progress around the world. Often these projects are located in sensitive ecosystems. K-UTEC project and support actual a solution mining operation of a Carnallite deposit for a Chinese customer in South-East Asia. This work comprises a comprehensive geological and geomechanical modeling as well as stability analyses. Furthermore the cavern design and brine field layout as well as the planning of the brine processing and the plant design. The present paper introduces this project as a case study. The application of a special solution mining procedure and processing design ensures an emission-free mining operation (Zero Disposal Plant). The emission-free operation is achieved by utilizing the full extent of the caverns to dispose the liquid solutions from processing. The presentation of principal salt processing and technical equipment will be rounded by information about the geology of the deposit. Since the deposit includes a number of sensitive minerals, such as Tachyhydrite and Bischofite the presentation comprise a lot of interesting items with special view at the brine field operation. K-UTEC designed and delivered a special blanket measuring system and a well cement according the request of the customer. K-UTEC, a research and engineering company with more than 60 years of experience in the sector of potash and rock salt mining, developed the world's first solution mining operation for Carnallite in Germany more than 30 years ago. In recent times K-UTEC served in different solution mining projects worldwide, with special view at the environmental impact, as well as the optimal utilization of the deposits.

Aug 1, 2013

By Dani J. Alldrick, Alastair J. Sinclair, Colin I. Godwin

"The Stewart mining camp has a long history of precious and base metal mining. The camp is abundantly mineralized, with more than 200 widespread, varied, vein prospects, deposits and orebodies. These show wide variations in the mineralogy of ore, gangue and alteration assemblages, and wide variations in textures and structural settings. This report establishes the timing of the different metallogenic epochs and suggests a specific exploration application for systematic leadisotope analyses.Galena lead isotope ratios from a range of mineral occurrences indicate that all these varied deposits formed during two main mineralizing events. Lead isotope data from the Stewart mining camp do not provide absolute ages for the formation of mineral deposits, but the relative distributions of data are consistent with dates determined in other studies. One ore-forming episode occurred in the Early Jurassic and the other in the Middle Eocene. Both metallogenic epochs were brief, regional-scale phenomena. Some deposits from the younger mineralizing episode were emplacedadjacent to or superimposed on the older deposits.Field and laboratory studies show that the two metallogenic epochs are characterized by different base and precious metal suites: Early Jurassic gold-silver-zinc-lead-copper; and Middle Eocene silver-lead-zinc. Therefore, showings of different ages have different base and precious metal potentials and deserve different exploration emphasis. Lead isotope studies provide a reliable, cost-effective method for evaluating the age and commodity potential of small or recently discovered mineral showings and for setting exploration priorities on properties with several varied mineral occurrences. The determination of the age and metal potential of a prospect at an early stage of exploration may govern the urgency, intensity or even the necessity for further exploration work."

Jan 1, 1993

By T. P. Kostek

"Historically, gear pumps and motors have been popular in the mining industry because of their competitive cost, simple yet rugged construction, ease of rebuild, and relative long life and insensitivity to contamination. However, with the ever increasing ""popularity"" of fire-resistant hydraulic fluids, both users and manufacturers of gear equipment must make special considerations to enable the equipment to continue giving satisfactory performance even with the water-containing fluids.The paper discusses 60-40 invert emulsions and waterglycolsIntroductionMuch information has been published on the specific characteristics of the various types of fire-resistant hydraulic fluids. Fluid manufacturers' literature and other publications have dealt with such specifics as fire resistivity, seal compatibility and wear rate characteristics. Gear pumps and motors have been, and will continue to be, applied successfully in hydraulic systems employing both the ""invert"" emulsions (60-40) and water-glycols as the hydraulic fluid.Because most external spur gear equipment has been designed to function with petroleum oil as the fluid medium, certain guidelines must be followed to ensure satisfactory service life. FluidsThere are a number of different types of fluids which fall in the category of"" fire-resistant"" , the most common'being phosphate esters, water-in-oil emulsions, oil-in-water emulsions and water-glycols. The two in most prevalent use today as hydraulic fluids are the water-in-oil emulsions and the water glycols"

Jan 1, 1980

By W. J. D. Stone

"INTRODUCTION Over the past decade, a number of publications have described the advances in High Intensity Wet Magnetic Separation. A number of significant, but small capacity installations were made and are successfully operating. These were followed some three years ago by larger installations treating ilmenite gravity concentrates; at least one machine treating 25 tons per hour of new feed was installed and is successfully operating.However, this still did not result in general acceptance that High Intensity Wet Magnetic Separation could be applied on a large scale. Neither did it dispel the feeling that High Intensity Wet Magnetic Separation was ""expensive"" and hence, confined to small scale – high value applications suchas the cleaning of tin concentrates. In addition, there is the usual reluctance of being the ""guinea pig"" which has resulted in waiting to see ""someone else"" make the first large installation decision. Such a decision and installation has now been made.Therefore, the purpose of this paper is to show that High Intensity Wet Magnetic Separation has been commercially accepted on a large scale and to show its general application to the base metal mineral industry.Examples are confined to a few specifics due to the large volume of preliminary test data that is available. The art has now reached the stage where much of the preliminary work should be taken through to serious evaluation."

Jan 1, 1971

By K. Karan

Oxygen reduction reaction in PEM fuel cell cathodes involves participation of three reactants - oxygen, hydrogen ions, and electrons. Electrochemical reaction in the catalyst layer is, therefore, influenced by how these species are transported to the reaction site. The two-phase boundary locations at which percolating networks of ionically conducting electrolyte and electronically conducting Pt/C meet are feasible reaction sites. The electrolyte phase also provides pathway for the transport of dissolved oxygen. Most of the 3-D models describe the catalyst layer as an ultra-thin layer, thereby, losing useful information on the distribution of electrochemical reaction rate. In this paper, we extend our previous work on 2-D cross-the-channel modeling of PEMFC cathode based on agglomerate catalyst layer. In particular, we take a closer look at the influence of proton conductivity on the reaction rate distribution in the catalyst layer. As well, we re-examine the role of anisotropic transport coefficient of the porous transport layer (PTL), commonly known as the gas diffusion layer, on the current density distribution under the channel and the rib of the flow-field plates. Results from both a 2¬D and a 3-D models will be presented.

Jan 1, 2005

By Marty Hudyma

Mining-induced seismicity and rockbursting is one of the primary risks in deep mines. Seismic data management software has been created to facilitate analysis of mining-induced seismicity. The Mine Seismicity Risk Analysis Program (MS-RAP) is a purpose built database with mine seismicity analysis tools. One of the primary features of MS-RAP is the creation of seismic hazard maps in quasi-real time. The seismic hazard maps identify areas that are more prone to large seismic events and rockbursts, allowing risk management measures to be focused on the areas of greatest risk. These maps allow mining engineers to be more proactive about identifying and managing seismic related geomechanics risks in mines.

Oct 1, 2009

By D. L. Millar

The hydraulic air compressor (HAC) is driven only by water, held up by a dam, to create relatively low head (typically 10-20 metres), such that the developed hydropower is used to cause flow in openings deeper underground. Air is entrained in the water at the inlet to the sub-surface openings (an air to water volume ratio of 1:1 is reported to be optimal) and is compressed as it is carried along by the deepening water flow. At depth, and with lower water velocities arising from larger cross sectional area tunnels, air bubbles separate out of the water flow and are collected in a receiver space above the flowing water. Water, free of air, then passes back up a return shaft (up-pipe) and rejoins the river or stream flow. In principle, an HAC can produce any pressure and flow rate required, given large enough shafts and enough water supply with head sufficient to overcome frictional resistance in the sub-surface tunnels. Practically, as air solubility in water increases with pressure, HAC installations with depths greater than 100 metres may lead to higher rates of compressed air loss, without special separation measures. A modern HAC application for mine refrigeration and cooling is presented.

Aug 1, 2013

By M. R. Shadnam

This contribution provides an assessment of research and development efforts to optimize SOx, NOx and mercury capture in flue gas. Coa, characteristics and combustion conditions in a power plant have an impact on the types and concentration of flue gas pollutants. These factors can also affect the amount of pollutant removed. This contribution would also provide a comparative study of the technologies that holistically aim remova, of SOx, NOx and mercury altogether in coal-fired power plants. A portion of this contribution provides background information on regulatory drivers.

Jan 1, 2010

The uranium ore processed by the McClean Lake Operation is co-mineralized with niccolite, rammelsbergite and gersdorffite (nickel arsenides). During the strong acid leach process, the majority of the reduced arsenic is oxidized and liberated into the lixiviant solution as As+5. Following uranium extraction, the residual raffinate solution, enriched in As+5, reports to the tailings preparation process. In this process, Fe+3 is first added and mixed with raffinate (pH~1) to achieve a Fe+3/Astotal molar ratio of at least 3. This is followed by two stages of neutralization, using slaked lime to achieve a solution pH of 4, and approximately 7.5, respectively. Synchrotron based x-ray absorption techniques (XANES, EXAFS) applied to neutralized raffinate solids and tailings samples collected from the tailings management facility provide evidence that arsenic has been precipitated as a poorly crystalline form of the mineral scorodite (FeAsO4?2H2O).

Aug 1, 2010

By R. Binning

"Economic high density mineral reclamation and subsequent transportation of solids through a pipeline presents many formidable engineering problems.Mineral reclamation system design by theoretical formulas is almost impossible because solids composition, ie. concentration, velocity, moisture content, solid size, etc. can only be controlled within a broad pumping range.Traditionally this has restricted pumping to relatively dilute slurries whereas it is usually preferred, because of economic considerations to reclaim as high a concentration as possible.At Toyo/De-Velde Corp. we recognized these pumping limitations and began to develop and manufacture a range of standard and auxiliary equipment that would exceed these technical restrictions.MATERIAL RECLAMATION & PIPELINE INJECTIONTo minimize fluid usage and increase material reclamation efficiency we designed a submersible dredge mixing pump that uses most of its energy to pick up material from rest, mix it with fluid into a highly concentrated slurry then push it firmly into a pipeline.Where material is too compacted to be mined by the standard submersible mixer pump, auxiliary high torque self contained submersible excavators can be fitted around the periphery of the mixer pump. This is to facilitate excavation and break up of the compacted material into a slurry.High flexibility of this system can be achieved by combining the many equipment variations available into the most efficient format to fit individual site requirements.Whatever combination of equipment is selected, torque is nullified by counter rotating excavators against each other. This increases effective excavator/material bite torque but also allows mixer/excavator rig suspension by cable for deep water material recovery."

Jan 1, 1985

By O. S. Perry, D. F. Kidd

"BEAVERDELL IS IN the Interior Plateau of British Columbia, 25 miles east of Penticton, B.C. In 1897, small but rich silver-bearing veins were found on Wallace Mountain, 2 miles east of Beaverdell. Production from the camp, at first of a modest character, started in 1901 and has never ceased. Over 90 per cent of the values in the ores have been in silver. Remaining values present are in lead, gold, zinc, and cadmium.There have been four principal mines in the camp. A fifth is approaching production. The four mines lie within a northeasterly trending rectangle about 5,000 feet long and 2,000 feet wide, the fifth mine being at the northeast end. From southwest to northeast the mines, with their silver production to Sept. 30, l 955, are: -Wellington Mine - 1,463,948 oz.Sally Mine (includes Rob Roy claim) - 1,930,124 oz.Bell Mine - 3,460,815 oz.Lass Mine - 12,557,956 oz.Other production - 331,252 oz.Total, Beaverdell Camp - 19,744,095 oz.The camp is near the centre of an area geologically mapped in 19 l l by L. Reinecke for the Geological Survey of Canada (1). The rocks of the camp comprise:1. Beaverdell stock of porphyritic quartz monzonite;2. Westkettle batholith of quartz diorite;3. Wallace formation of tuffs and lavas.The Wallace formation borders the east edge of the camp, and has been intruded by the Westkettle batholith. The batholith is the host rock for the orebodies. The Wallace-batholith contact dips gently east. Some of the Beaverdell ores at depth, while in the batholith, are under Wallace formation mapped on the surface above.West of the camp, Reinecke mapped a stock one by one and one-half miles in size, of porphyritic quartz monzonite, which he considered much younger than the Westkettle quartz diorite (I). Recent petrographic work by White and Dolar-Mantuani (3) suggests that in the vicinity of the camp the Westkettle batholith is more quartz monzonite than quartz diorite, and little different in composition from the Beaverdell quartz monzonite. They suggest a consanguinity with the Westkettle batholith."

Jan 1, 1949

By Nelson Lawrence

An Electrical Risk Management/Inspection Program has been designed specifically for the mining sector in order to provide electrical code expertise and systemic gaps in electrical systems. Goals include improved safety and productivity, reduced injuries and help to enable businesses to better comply with the electrical codes and regulations that govern them. The Electrical Risk Management/Inspection Program is now recognized by some of the world?s largest mining organizations. Since June, 2001 these electrical safety advisory services have been available to underground and surface mine sites throughout Ontario and are now offered throughout Canada and around the globe. This program is also currently being applied to review new electrical installations for mine construction projects thus improving the safety and reliability of mine site electrical systems.

May 1, 2006

By Andrew Bamber

Outline ?Background to Mine-Mill Research at UBC ?Mine Mill Integration ?In situ mining methods ?Underground Pre-concentration ?System Design and Supporting Technologies ?Case Studies: ?INCO -McCreedyEast Mine ?Placer Dome ?Porcupine JV ISL Study ?Musselwhite, South Deep ?Falconbridge ?Fraser Copper ?Thayer Lindsley ?Wayside Gold, other scoping studies? ?System Designs ?Summary ?Future work ?Conclusion

May 1, 2006

By S. Brophy

Controlled Short Circuit ? Metal Inert Gas (CSC-MIG) welding is a process that can be referred as a "Cold Welding" technology. The CSC process is based on accurate control of the welding wire position, thus the mandatory requirement for the automation of the process. One of the main advantages of the CSC-MIG process is the rapid solidification of the deposited material, resulting in weldments displaying low porosity contents, and enabling the joining of thin sheet materials. These characteristics render this process an ideal one for freeforming of components, where rapid solidification would be efficacious. This presentation will focus on the progress made towards the freeforming of Al-based components in the NAIN laboratory at McGill University. The relationship between the filler metal used, freeforming (deposition) parameters, resulting microstructure and mechanical properties will be presented.

Jan 1, 2011

By T. Takahashi, K. Oyamada, Y. Miyata, T. Isoo

The carbonation reaction of steelmaking slag has been known for many years. However, the size of blocks manufactured from this by-product material has been limited due to the difficulty of achieving a uniform reaction throughout the block. Using newly developed conditions, large porous slag blocks (1.0 x 1.0 x 0.5 m) were produced by car¬bonation of steelmaking slag with the optimum amount of water and supplying CO2 deep into slag powder compacted in molds. The development of these blocks has great poten-tial to solve the problem of slag utilization, for example, by recycling slag in large car¬bonated blocks for artificial fish reefs and seaweed cultivation beds. This paper de¬scribes the carbonation reaction, the new process for producing large slag blocks, and the utilization of blocks in past and recent years.

Jan 1, 2004

By Ferenc Molnár, David H. Watkinson

Abstract - Cu-Ni-PGE footwall ore deposits were studied in the McCreedy East and Whistle mines along the North Range, and the Lindsley and Little Stobie mines along the South Range of the Sudbury Igneous Complex. The footwall ores in these localities differ from typical magmatic Fe-Ni-Cu- PGE deposits in the Sudbury mining camp: they have higher Cu/Ni ratios, higher PGE content, veinlike appearance and ubiquitous association of ore with hydrous silicates. Results of comparative fluid inclusion petrography and microthermometry of footwall ores indicate that high temperatures (300°C to 480°C) and heavy-metal rich saline (up to about 40 NaCl equivalent wt% salinity) fluids were associated with the formation of the PGE-rich footwall ores at moderately high pressures (around 2 kbars). However, several, possibly independent fluid circulation stages were also found at the different localities and there also are differences in detailed characteristics for ore-forming fluids especially comparing data from the North Range and the South Range. Thus, in addition to the high temperature and salinity of fluids, there are local variations in the nature of hydrothermal processes. These differences may be related to the diverse origin of fluids (magmatic, metamorphic, and formational brines) and their differing extents of interaction with the compositionally different footwall lithologies.

Jan 1, 2001

By Roger St. C. Smart, Paul Weber, Joan E. Thomas, William M. Skinner, Warwick Stewart, Stuart Miller

For mine sites affected by acid rock drainage (ARD) or with a potential future ARD issue, the prime consideration is not only the classification of different waste rock as potentially acid forming or non acid forming but also the peak acid (and metal) release rates and expected ARD duration during which effective ARD management and acid neutralisation capacity (ANC) are required. Methods for assessment of this ANC (e.g., Sobek tests) are already available but can be unreliable in ARD containing significant proportions of framboidal pyrite or iron carbonates. The measurement of negative ANC values and the release of S to solution showed that significant sulfide oxidation may occur prior to and during testing in samples containing reactive (particularly framboidal) pyrite resulting in serious underestimation of the original ANC. A simple methodology with dissolution in Ar-purged water before ANC testing, removing ferrous salts, and sulfate assay after ANC testing corrects these effects. Results also showed that a significant lag period (up to 432 h) may be needed for complete hydrolysis of Fe associated with the standard Sobek ANC testing of, for instance, siderite. Hence, the ANC of iron carbonates is usually significantly overestimated. By filtering and the addition of H202 until there was no subsequent pH drop (due to Fe hydrolysis reactions), followed by back titration to pH 7.0, the ANC for siderite was similar to the ANC determined after 432 h lag by the Modified Sobek ANC test and to the mineralogical carbonate ANCcarb determined by calculation based on electron probe micro-analysis. A chemical ANC calculation, based on neutralising cations released to solution, has provided a method to quantify the short-term ANC of carbonates and silicates in simple mixed mineral assemblages and waste rock samples. Results showed that silicate ANC can be more important in short-term neutralisation than carbonate ANC in low carbonate samples. In the longer-term, decreasing sulfate and metal loads with increasing pH values suggests that eventually sulfide acidity generation rates will match the longer-term inherent acid neutralisation rates of the sample derived from silicates. A kinetic ANC measurement for silicates, after steady state dissolution is reached, that indicates the number of hydrogen ions neutralised/m2/yr has been developed. These values can be used in estimates of the net acid production profile from wastes with low (and decreasing) pyrite content after the short-term ANC is exhausted.

Jan 1, 2004

By D. G. Dixon

A novel technology for leaching copper from primary copper concentrates has been developed at UBC. This patented technology takes advantage of the galvanic couple between pyrite and chalcopyrite to ensure rapid and complete oxidation of chalcopyrite under mild conditions in acidic iron sulfate solution, without the need for microbes, ultrafine grinding, or chemical additives such as chloride, nitrate, or surfactants. Copper recoveries of 98% or greater can be achieved at 80°C under atmospheric conditions in as little as 4 hours of residence time. The process is selective for chalcopyrite over pyrite, generates near-quantitative levels of elemental sulfur, and is fully compatible with conventional solvent extraction and electrowinning of LME Grade A copper cathodes. In this paper, the fundamentals of the Galvanox ? process are reviewed, and selected results of batch leaching tests on various concentrate samples are presented and discussed.

Jan 1, 2007

By M. B. McClenaghan

"The Ontario Geological Survey completed a regional till sampling project between 1984 and 1988 in the Black River Matheson (BRiM) area of northeastern Ontario. The project was designed to aid mineral exploration in the area by documenting the Quaternary stratigraphy and by providing a database of till geochemistry. This paper summarizes the results from the sonic overburden drilling component of the BRiM project carried out in areas of thick drift (> 5 m). Results from till sampling in areas of thinner drift (<5 m) have been presented in a separate paper. Approximately 1100 till samples were collected from 225 sonic drill holes. For each sample, the non-magnetic heavy mineral (>3.3 S.G.) and fine (-250 mesh) till fractions were analyzed geochemically and visible gold grains were recovered by panning.Gold and other multielement geochemical data were plotted using proportional symbols to highlight anomalous areas and to demonstrate how to evaluate and interpret a very large geochemical dataset. Thresholds for identifying anomalous concentrations of Au in till samples, defined using the 95th percentile, are 1500 ppb and 12 ppb for the heavy mineral and fine fractions, respectively. The heavy mineral fraction of older ti1ls and to a lesser extent, Matheson Till, display a number of significant gold anomalies in the study area, which in a few cases, are associated with base metal anomalies. The vertical position of gold anomalies in Matheson and older ti1ls varies from directly on bedrock to several meters above the bedrock surface and can provide information of relative ice transport distances."

Jan 1, 1994