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By R. Noorani, M. Cai

"Excavation of deep underground openings in highly stressed grounds can generate new fractures near the openings. As a result, rock mass bulking may occur, leading to large wall deformation. A better understanding of brittle rock failure and the associated fracturing process at the laboratory scale is an essential step towards evaluating dilation behavior of rocks. A grain-based model that can capture dilation behavior of rocks under various loading conditions at the laboratory scale can be a useful approach to study rock mass bulking at the field scale. The aim of the paper is to study the dilation behavior of rocks at the laboratory scale employing numerical simulation. A modified grain-based model is used to simulate the macroscopic response of crystalline rocks by considering micro-fractures at the grain scale. Grains generated with the Voronoi tessellation are allowed to fail in tension or in shear using a strain-softening model. Damage is represented by either grain boundary fracture or grain failure, or the combination of the two. As stress increases, the process of damage, fracture initiation and coalescence in rocks can be captured.The grain-based model was calibrated using test data of the Lac du Bonnet granite and a parametric study was conducted. Numerical simulation results showed that the proposed modeling approach is able to capture most of the mechanical properties, fracture pattern, and dilation behavior in both unconfined and confined loading conditions. In an unconfined compression test, interactions of microscopic fractures may lead to macroscopic shear or axial splitting failure depending on the chosen micromechanical parameters. Numerical experimental results show that the dilation behavior of the model is strongly related to the failure mechanism of rocks. Tensile-failure-dominated failure mode generates large dilation due to the formation of new cracks that are sub-parallel to the loading direction. On the other hand, shear-failure-dominated failure mode produces small volume increase. One significant finding from this study is that in order to capture large dilation using grain-based UDEC models, intragranular grain failure should be considered."

Jan 1, 2015

By C. Stapel, I. C. Tânczos, R. J. De Meijer

"Abstract -In recent years the Environmental Research Group of the KVI has been developing a number of radiometric techniques that may be employed in mineral sand exploration. These techniques involve: radiometric fingerprinting for assessing sand provenances and mineralogical composition; thermoluminescence for dating and provenance determination of sediments; a towed seabed detector to map seafloors for radiogenic heavy minerals and assessing heavy mineral volumes; and simplified transport mechanism models to explain and predict heavy mineral concentrations.All techniques exploit the property that heavy minerals as a group contain concentrations of naturally occurring uranium and thorium that are a hundred to a thousand times higher than in light minerals. In this paper the physics of a number of methods will be described together with a number of results. Based on these results potential applications to mineral exploration and mining are discussed."

Jan 1, 1994

By G. Rong, W. Du

Stability of some potential unstable blocks in the left bank slope of Baihetan hydropower station is evaluated in this paper using the three-dimensional (3D) limit equilibrium method. The Baihetan hydropower station is in the downstream of Jinshajiang River, China. The geological condition in the river valley is complex, and many large discontinuities are detected in the slope of the two banks. As a result, much attention should be paid to the stability of the slope in the feasibility study stage. Because the left bank slope is an oblique consequent one, we mainly focus on the slope stability analysis in the left bank. Comprehensive geological exploration is conducted in the studied area and the detected discontinuities are well researched. By building a 3D geological model of the left bank slope, three potential unstable blocks which are close to the dam site are detected. An irregular wedge analysis method is then used to calculate safety factors of the three blocks under three conditions, which are natural condition, rainfall condition, and seismic condition, respectively. It is found that the safety factors of the block 1# and the block 2# are quite low when compared to the suggested values. Extra care must be exercised when excavating the slope near the block 1# and the block 2#. A preliminary reinforcement is also suggested.

Jan 1, 2015

By Edgar A. Manker

"Today's market for columbium has only developed in the last two decades, and in this sense it is ""newer"" than molybdenum, vanadium and most other steel alloying elements. In this short period, it has assumed a very important role in steel alloying and in superalloys. From a few hundred thousand pounds of columbium in 1960, consumption has grown to nearly 30 million pounds per year, with a market value approaching two hundred million dollars.To assess the outlook for columbium, we will first consider the historical development of consumption and supply, particularly noting that all of today's major mines were developed during the last two decades. From current production, we will attempt to reasonably project the future. This future may well include new producers, particularly some producing columbium as a co-product with tantalum.The growth of current applications, and emerging new applications, will be considered with regard to future consumption and in relation to future trends in pricing.IntroductionThe nineteenth century was a busy time for the discovery and naming of new elements. Among those discovered were columbium in 1801 and niobium in 1844. Although it was later shown that columbium and niobium are the same element, the two names are still used today. Niobium has been pronounced the ""official"" name by the International Union of Pure and Applied Chemistry, but columbium is still widely used in commercial practice, and we have chosen to use columbium in this paper."

Jan 1, 1981

By Noel W. Kirshenbaum

Difficulties and costs of transport markedly affect Canadian mineral producers because of distance from markets, weather conditions and rugged terrain. The chemical and physical nature of sulphide concentrates presents additional difficulties in handling and transport, resulting in higher costs which are ultimately borne by the mineowner. Troublesome properties include the thixo-tropic character of wet concentrates, freezing, susceptibility to autogenous heating, and fine particle size causing spillage and dusting losses. Canadian mineowners and shippers must contend with these problems and with stringent regulations governing the maritime shipping of concentrates. A "systems approach," in which complementary techniques in materials preparation, handling and transport are integrated, could reduce freight costs and losses for those selling concentrates, facilitate operations for those carrying and handling them and, in some cases, improve metallurgical processes in smelters receiving them.

Jan 1, 1969

By V. Loya

Metallic foams (MF) are relatively new materials with a combination of attractive properties (permeability, high surface area, thermal and chemical stability, etc,), They can be produced from different materials and can be manufactured using various processes, Due to their unique properties, they find applications in different sectors of engineering, such as energy absorption, filtration, heat dissipation, etc, For many applications, the permeability is an important parameter to characterize and optimize, Most of the recent literature on the subject studied the permeability in the low velocity range. The present study was carried out to have a better understanding of permeability for greater velocity ranges, An equipment was designed and built for this purpose, Pressure drop measurements were made across the thickness of open-cell nickel foams, Pore and window sizes were measured by image analysis on SEM micrographs, The experimental results are in relatively good agreement with the Hazen-Dupuit-Darcy model (R2>98%), The permeability is affected by pore size, porosity and the normalized projected area of the connecting pores (ie. windows).

Jan 1, 2005

By K. Esmaieli

This paper addresses issues associated with ore pass degradation caused by material impact. A series of numerical experiments, using the particle flow code, were undertaken to investigate the influence of various finger raise configuration. This has allowed the identification of favorable configurations. The results of this analysis, when coupled with field observations, can contribute to the design of ore pass systems that can prolong the useful operating life of ore pass systems.

May 1, 2009

By Adrian E. Scheidegger

"AbstractThe possibilities of deriving pertinent information about fractures in an oil pay from data obtained by core analysis are investigated. It is shown that it is possible to obtain an estimate of the fractured area per unit volume of the pay, and that the size of the fractures can be estimated if their shape is known. A suggestion of a routine procedure for the analysis of fractures is given.1.-IntroductionMany oil fields are producing essentially from cracks or fractures. Where this is the case, it is important to be able to obtain a knowledge of the size and distribution of those fractures in the oil pay. This knowledge has to be derived from the analysis of cores taken from the fields, as it is generally impossible to follow a fracture through the pay by direct means. The necessity of using statistical methods to extrapolate the meagre information obtained from the cores of the wells is therefore indicated.It is known that the fractures are much bigger than the diameter of the cores; thus, if they strike a core, the latter will generally fall into two pieces. The angle of the fracture with the vertical can be measured and, if oriented cores are taken, the exact position of the surface element representing the intersection of the fracture with the drill stem can be determined. Sometimes the edge of a fracture can be seen in a core. The number of •Cores that show such an edge can be noted. Of course, one has to be careful to distinguish between original fractures in the pay and fractures in the core caused by drilling operations. Only the former are relevant."

Jan 1, 1955

By P. Dinham, G. C. Summerton, N. McCulloch, S. Dowling, D. C. Craig

"Development of a process for the treatment of a nickel copper matte rich in the minerals heazlewoodite, chalcocite and bornite has demonstrated significant base metal recoveries and metal separation efficiencies. The determination of chemical and mineralogical changes occurring in the individual leaching stages in laboratory experiments has enabled a better understanding of the complex leaching chemistry. The chemistry and mineralogy of the piloting and laboratory processes are discussed.INTRODUCTIONThe nickel-copper sulfide ores of the South African Bushveld Complex are among the most important Platinum Group Metal (PGM) bearing ores, and contain the world’s largest reserves of platinum. The treatment used in the recovery of PGMs from these ores includes three types of processes, namely ore concentration using physical techniques such as flotation and gravity separation, concentration by pyrometallurgical means, hydrometallurgical extraction of the base metals followed by the PGMs. Following milling of the ore, flotation involves the separation of high value minerals from gangue by taking advantage of the differences in their hydrophobicity. These differences are generally maximized through the use of a surfactant or wetting agent. Concentrates are then thermally treated and melted which brings about physical and chemical changes that enable the recovery of base metals and PGMs. The main aim of the smelting and converting process is to separate and eliminate the valuable metals from the bulk of the unwanted gangue and essentially all of the iron and to concentrate the metal VALUES (into a high grade converter matte. The matte can be further enriched by magnetic separation, producing a PGM-rich magnetic fraction and a base metal-rich non-magnetic fraction. The magnetic fraction is treated by hydrometallurgical processes to produce a PGM concentrate which is further refined to separate and purify the individual metals. The non-magnetic fraction is treated to produce marketable metal VALUES (such as nickel, copper, cobalt and to a lesser extent PGMs. The principal objective of any hydrometallurgical extractive process is to leach the desired elements selectively into an aqueous phase so as to separate them from the bulk of the material. (Crundwell, Moats, Ramachandran, Robinson and Davenport, 2011; Hundermark, Mncwango, de Villiers and Nelson, 2011)."

Jan 1, 2012

By F. Bosché

Previous research has shown that ?Scan-vs-BIM? systems are powerful to provide valuable information for tracking structural works (progress, quality, safety). However, the transferability of this capability to other construction areas such as MEP works has not been assessed so far. Comparatively, the construction of MEP systems, in particular pipes and ducts, tends to be more flexible with respect to the positioning of individual components, so that Scan-vs-BIM systems could be defeated when tracking MEP installation works. This paper presents recent results on the feasibility and performance of using a Scan-vs- BIM system to track MEP works. The approach followed is presented and then tested with two real-life challenging case studies were conducted simultaneously but totally independently in Canada and Italy. The results show that, as expected, pipes and ducts tend to be more loosely positioned than structural elements leading to a poorer performance of the Scan-vs-BIM system. Nonetheless, it appears that the system works well to assess the level of conformance of site installation works, providing valuable information for estimating emerging performance metrics like ?percent built as-designed?. In addition, the proposed system could also be useful to accelerate and thus reduce the cost of delivering as-built BIM models for in the case of new builds.

Aug 1, 2013

By Roy O. Ifill, W. Charle Cooper, Alan H. Clark

"Queen’s UniversityIn representative, run-of-mine samples from the Panel and New Quirke mines of the Elliot Lake uranium district, Ontario, brannerite, ametamict uranous titanate, occurs in microscopic grain-aggregates which display wide variations, both in textural habit and in the relative proportions of brannerite, titania polymorphs and/or “uraniferous titania”. As is widely documented, much of the brannerite occurs as trellis-like arrays of laths and needles pseudomorphing rutile oranatase. In some cases, the laths and needles are cemented by coffinite. Brannerite, with an average composition of (U0.629Th0.039Ca0.20)(Ti2.199Fe0.13)O69contains =3 wt% Th and is distinctly Ti-rich relative to the ideal composition, UTi2O6. Much of the Si reporting consistently in electron microprobe analyses (between 1 wt%and 5 wt%) is tentatively attributed to contamination by the quartz-sericite matrix, and a minor proportion is attributed to the presence of coffinite intergrowths. “Uraniferous titania” (average par-tial composition by weight: 10.8% U, 0.3% Th,32.9% Ti) is considered to represent an intermediate stage in the conversion of titania to brannerite.The leaching behaviour of brannerite in its different modes of occurrence was studied qualitatively by the rotating-disc (polished section) method in H2SO4and HCl solutions at 25° to70°C. Redox potential was not measured. The progress of the dissolution of the individual brannerite crystallites and grain-aggregates was monitored by optical and scanning electron microscopes. Regardless of its morphology and texture (laths or needles, reticulate or blocky),brannerite is not readily leachable. Regardless of the process conditions, the rate-controlling step appears to be the initial leach-pit formation. These pits expand radially through the aggregate as leaching proceeds. This dissolution mode is independent of the relative amounts of brannerite and titania, i.e. the type of grain-aggregate. Secondary coffinite intergrowths are readily leachable and enhance the overall leaching kinetics of brannerite by accelerating leach-pit formation. These data provide, for the first time, information on the controls on the leaching of the uraniferous phases which dominate the lower-grade ores in the Elliot Lake district."

Jan 1, 1996

By P. deH. Eastcott

The paper summarizes a slide presentation made during the CIM Mechanical-Electrical Operators' Conference, held at Sudbury. Ontario, January 25-27, 1977. Its scope has been limited to a few specific aspects of modern Canadian hoisting plant practice that are likely to be of interest to operating personnel. It is intended to serve as a brief review of established methods discuss in more detail the present state-of-the-art and suggest trends that will appear as products during the next few years.

Jan 1, 1977

By David G. Baskin

"THIS DEPARTMENT is unique in that it operates in the production stream and also provides an essential service. Its operating function consists of scheduling an ore train to haul 10,000 tons per day over 17.1 miles of track and switching all incoming and outgoing rail equipment on 2.2 miles of track at the minesite and 6.2 miles of track at the metallurgical site. The service it provides is traffic control of all incoming commodities and all outgoing concentrates, metals and acid by rail and truck, even extending to port and ship control for overseas shipments (Fig. 46). Although they cover many miles, the railroad and traffic department employees operate very efficiently, as indicated by the following organizational chart:Railroad and Traffic Superintendent ................ 1Railroad Supervisor .............................................. 1Assistant Railroad Supervisor ........................ 1Track Foreman ...................................................... 1Trainmen ............................................................... ... 4Switchmen ............................................................... 4Trackmen ................................................................ 10Traffic Supervisor ................................................ 1Clerk Steno ............................................................ 1Clerks ...................................................................... 3"

Jan 1, 1974

By James F. Archibald

A research effort has been undertaken, under WSIB sponsorship, to characterize the support capabilities of conventional and innovative spray-on lining materials for mitigating dynamic failure effects created by simulated rockbursts. Conventional spray support media, such as shotcrete and fibrecrete linings, and a variety of new spray-on lining materials (TSL?s), typically polymer-type thin coatings, were subjected to simulated rockburst influence. For baseline comparison, conventional rockbolt and boltand- mesh support products were also evaluated. Observation of lining performance was undertaken through completion of field scale support and rock detonation trials. Controlled blasting tests were conducted at the Queen?s University Explosives Laboratory to examine the effectiveness of the variety of surface coating agents for modifying dynamic rock spalling processes. All tests were performed upon largely undisturbed and homogeneous rock materials in highly repeatable fashion. Both conventional and innovative TSL-type surface lining materials were subjected to ?rockburst? exposure in rigorously-controlled blast trials. All blasts were observed seismically and photographically to provide detailed information concerning rock motion, surface fracturing, ejected fragment motion and support liner survivability characteristics. These material comparison trials were performed to assess the relative effectiveness of a wide range of currently-available area support techniques for suppressing hazards associated with dynamic rock ejection. The results of this study validates that thin, sprayon linings may be equally as effective, and often better, than conventional support materials at mitigating rockburst or like damage in highly stressed mine environments.

May 1, 2003

By M. Redfearn

"DUST COLLECTION EQUIPMENT LIST Primary Dust CollectorModular Mikro-Pulsaire - Model 2G1-96TR Capacity: 20,000 c.f.m.Bags: Total of 288; 8' x 4 1/2"" diameterMaterial: Dacron HCE feltAir to cloth ratio: 7.55/1Bags are changed every 6-9 months. Sent to A & L Services for cleaning at a cost of less than 1/3 the price of a new bag. No new bags have been required since start-up 4 years ago.Blow hack: 35 c.f.m. at 100 p.s.i.Fan: Joy Manufacturing, Model 3300, Type 4S, Backward inclined fan.Impeller: 33"" diameter36"" diameter Inlet33"" diameter Outlet at 3200 f.p.m. velocity1945Motor:,60 H.P., 1780 r.p.m.Capacity: 23,400 c.f.m.Design:,20,000 c.f.m.,•Actual:,17,500-19,000 c.f.m. depending on bag condition.Dust Slurry Agitator: Port-a-flo Model 050-350Major Maintenance:The fan was sped up from 1830 to 1945 r.p.m. and balanced at the higher speed. Several months later the impeller destructed beyond repair. A new shaft and impeller was installed, casings straightened, and bearings reused. Unit is currently running at 1945 r.p.m. No definite cause for the impeller failure has been found, although it might be attributed to improper balancing."

Jan 1, 1976

By G. Wren

As base metal sulphide resources become increasingly challenging to process, producers seek alternative options to treat concentrates. This study considers the mineral, elemental, and leaching character of a West Australian nickel sulphide deposit (Cosmos Nickel Project). After a brief review of the published work bench top leach tests were conducted to examine the factors which impact the kinetics of nickel sulphide leaching such as particle size, temperature, acid strength and type, concentration of copper sulphate and sodium chloride, and oxygen partial pressure. The effect of sodium chloride was considered due to the common occurrence of hyper saline water at West Australian nickel sulphide mine sites. Ultrafine grinding to an 80% passing size of 10 µm resulted in high nickel leaching efficiency. Moreover, higher concentrations of acid, copper(II) and sodium chloride also gave higher nickel and cobalt leaching efficiencies but arsenic precipitated as FeAsO4. Under the most suitable conditions the extractions of nickel, cobalt and arsenic at 90oC after 6 hours were >95%, 90% and <5%, respectively. The comparison with results from high pressure operations indicates the possibility of using a hydrometallurgical flowsheet based on fine grinding and atmospheric pressure leaching and warrants further investigations.

Jan 1, 2014

By Sunil S. Gandhi

"The Mountain Lake deposit is a tabular sandstone-type uranium deposit, hosted by the basal unit of Middle Proterozoic Dismal Lakes Group. Uranium occurs mainly as sooty pitchblende disseminated in stratiform lenses within gently dipping quartzose sandstone. It is associated with copper sulphides, pyrite, hematite, and traces of nickel and cobalt arsenides and of silver.Exploration HistoryUranium showings on the PEC claim group were discovered during 1969 by an airborne radiometric survey carried out over the Dismal Lakes-Great Bear Lake area by Aquitaine of Canada Limited (Bizard and Salat, 1969). Some drilling was done in the vicinity of the showings in 1975 by the company under a joint venture with Eldorado Nuclear Limited but the results were not encouraging (Hassard and Woollett, 1975). During 1972, Trigg, Woollett and Associates Limited conducting surveys for Imperial Oil Limited, discovered numerous high-grade radioactive boulders scattered over a distance of several kilometres north and west of the showings, and the area north of the PEC claims was staked as the YUK claims (Ahuja, 1974). A systematic study of the boulder distribution and Pleistocene geology suggested a source additional to the showings. More intensive exploration followed, and in 1976 drilling just north of the PEC claim group boundary intersected the main deposit at a depth of 75 m to 150 m, beneath overburden up to 60 m thick. Part of the deposit extends into the PEC claim group which is under exploration by the Aquitaine-Cominco Joint Venture.The following brief description is based on the presentations in 1978 by F. Hassard of Trigg, Woollett and Associates Limited at the Geoscience Forum in Yellowknife, and by S.S. Gandhi of the Geological Survey of Canada at the Mineralogical Association of Canada Uranium Short Course in Toronto."

Jan 1, 1986

By J. S. Edwards

The ISASMELT? process is recognized worldwide as a modem, flexible, environmentally-friendly and low capital cost smelting technology. Due to the inherent simplicity, and the advanced process control that has been developed, personnel become competent within weeks of being introduced to the ISASMELT? technology. This compares with the years required to become proficient with alternative technologies. Copper smelters in Australia, USA, India, China, Peru and Zambia have installed ISASMELT? technology under licence from Xstrata Technology. In the secondary copper business, plants in Belgium and Germany are processing copper and/or lead materials in ISASMELT? furnaces in a two stage process. In a single furnace smelting is followed by converting. Both plants have exceeded design capacities and are continuously improving their performance. The next evolutionary step for the technology is the implementation of the continuous copper converting process on a commercial scale. The present work describes the design status of the continuous converting process - ISACONVERT?.

Jan 1, 2007

By Z. G. Tao, Y. Y. Peng, W. L. Gong, M. C. He

"This paper presents an overview of the major landslide hazards in open pit mines in China, the currently used landslide control and monitoring techniques, and development of a new slope control technique incorporating the reinforcement, sliding force monitoring, remote sensing and forecasting in one system in order to constrain the displacement of the sliding blocks in the landslide to minimized the influenced area and provide precise warnings timely for the imminent landslides. For implementation of the new technique, a novel rock cable with large deformation and high resistance (also known as HE cable) was developed, which can elongate as long as 2m. At the same time, the necessary and sufficient condition for initiating a landslide and energy balance equations are formulated. Based on the proposed mathematical models and Beidou satellite system, the software and data transmission hardware for remote sensing and forecasting were developed the new landslide control technique has been applied successfully in 245 landslide sites in 12 provinces across China. In this article, two practical application cases in the open pit mines are reported.INTRODUCTIONChina is one of the countries in the world with the most widely distributed landslides and suffering the heaviest damage. According to the incomplete statistics, landslide hazards have caused death of hundreds of people and direct economic losses of several hundred million RMB each year. The landslide hazards have a great impact on the life and property safety of the people, safety of the infrastructure, as well as the social stability. Thus development of new techniques for forecasting and prediction of the landslides is imperative and of great importance. In general, the forecasting and prediction of the landslides consists of three major aspects, i.e. sliding time forecasting, landslide activity intensity forecasting and landslide hazard degree forecasting. Since a considerable part of the landslide-suspected area are adjacent to the residential areas or important infrastructures, development of the advanced landslide control and monitoring techniques to cope with the sliding time forecasting problem is more important.Over the past one hundred years, the most widely used slope monitoring techniques are based on displacement monitoring (Xu, et al. 2007; Toshitaka, 1998). In the early days owing to the limitation of the technology and equipment, the ground surface displacement and underground water level change were inspected mainly by man power for inferring the possibility of a landslide. In recent several decades, more and more ground surface displacement monitoring devices were brought to the market, such as the automatic total station, theodolite, digital level, borehole inclinometer and GPS based instruments, etc. Based on these modern techniques, some advanced instruments have been developed and applied to the landslide monitoring, for example, the “landslides early warning monitoring system” (Leonardo, et al. 2002), the “In-SAR” technique (Reevea, et al. 2000), the GPS and satellite geodetic survey based technique (Reevea, et al. 2000), and real-time telemetry technology (Xu, et al. 2007). These monitoring approaches have made significant contributions to the landslide disaster monitoring and forecasting. The major limitations for the ground surface displacement monitoring techniques are lie in the inconsistence between the displacement in ground surface and that in the sliding surface for the sliding mass, resulting in low degree of forecasting accuracy."

Jan 1, 2015

By G M. Thorpe

This paper discusses mine research at Inco, giving specific examples of research projects which illustrate the approach to mining problems. The first example covers the development of a new mining method, "undercut and fill," which was originated for mining badly broken-up pillars, but which is now rapidly replacing the square set method of pillar recovery. In the new method, ore is extracted in a series of successive horizontal cuts, progressing downward, a cut being completely mined and filled before the cut below is started. In the second example, improvements to the "cut and fill" method of mining are discussed. These improvements are the result of improved techniques and improved equipment, etc., with, in many cases, the former being made possible by the latter. The advances made have permitted the use of the "cut and fill" method at much greater depths than before. The third example is presented to illustrate research undertaken to obtain the earliest maximum advantage of the introduction of a new piece of equipment or material. For this purpose, the development of the "Under-ground use of AN /FO Blasting Agent " has been selected. Work on this project started in May, 1960, at a time when there was very little in-formation regarding the potentialities of AN /FO for underground blasting, either primary or secondary. By the end of 1961, AN /FO made up 64 per cent of the explosives used under-ground at Inco mines.

Jan 1, 1963