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By Z. Q. Liu, J. M. Du

"On the basis of analyzing current design and applications, the structure form, working loads and design principles of shaft sinking headframe are summarized in this paper. To overcome the insufficient bearing capacity and geometry size of the finalized shaft sinking headframe in China, a series of new large shaft sinking headframe were developed under vertical shaft construction conditions of maximum net diameter of 12.0 m and maximum depth of 1200 m. The new series shaft sinking headframe include two sets (with single sheave platform and double sheave platform), three dimensions (optimum shaft diameter <8.0 m, 8.0-10.0 m, and 10.0-12.0 m, respectively) for each set, and has innovation and optimization on structure of the sheave wheel platform (MU type) and bracing frame (REN and ZHONG type). The largest new shaft sinking headframe can arrange up to 4 hoisting equipment simultaneously and has bearing capacity more than 10000 kN. Two of the new shaft sinking headframe were successfully applied in practical engineering, such as the Hulusu auxiliary shaft, the Dahaize 1# auxiliary shaftand Sishanling auxiliary shaft. These applications showed that the new shaft sinking headframe has sufficient bearing capacity and reliable applicability. The new shaft sinking headframe could provide an effective guarantee for safety and efficiency sinking of deep-large shaft in the future.INTRODUCTIONShaft sinking headframe is one of the basic shaft sinking structures and it is mainly for hanging hoisting containers and sinking facilities in sinking a vertical shaft (Yu & Shi, 1991; Wang, Jing, & Liu, 2007). Currently, 7 types of steel pipe sinking headframe are used in China, which are mainly finalized by the Ministry of Coal Industry of China (Wang, 1988). As shown in Table 1, V-type is the largest of them and it is only suitable for sinking shaft of diameter less than 8 m and depth less than 1 000 m(Yang, 1982). However, with the increase of mining depth and scale of mineral resources in China, the diameter and depth of newly built vertical shaft are increasing continuously (Xie, Zhou, Xue, Wang, Zhang, & Gao, 2012; Qi & Pu, 2013). At present, the maximum net diameter of vertical shaft is close to 12 m, and the maximum depth is more than 1600 m (Yang & Chen, 2015; Xu, Yang, Liu, & Qin, 2015). The shaft sinking headframe has become the main restrictive factor for the development of sinking equipment, such as the height of muck discharging platform cannot meet the usage requirement of hydraulic umbrella driller, the size of sheave wheel platform is difficult to arrange the increasing hoisting and suspension equipment, the bearing capacity is insufficient to meet the needs of multiple hoisting loads in sinking a deep-large shaft, etc. Therefore, development of new shaft sinking headframe for deep-large shaft (>1000 m in depth and 8~12 m in diameter) is urgently required for China and also the whole world."

Jan 1, 2019

By R. E. Gilmore

PREAMBLE THIS PAPER comprises material presented in two separate &apos;Papers at the British Commonwealth Scientific Specialist Conference on Fuel Research held in London, England, in July, 1950. These papers are now available for publication in Canada, since only essential parts of the conference discussions, in addition to the resolutions resulting therefrom, will be published in the official Proceedings of the Conference. Inasmuch as the information presented concerns Canadian organizations and training facilities for fuel research, it should be of general interest to Canadian scientists, and especially to the Coal Division of the Canadian Institute of Mining and Metallurgy. Part I, the alternate title of which is Facilities in Canada for Fuel Research and for Exchange of Information and Staff, does not include research on peat, oil shale, petroleum oils in general, and natural gas, and omits studies of the geology, constitution, and production of coal. Special reference is, however, made to research on the heavy crude oils and bitumen of the Western Prairie Provinces, and particularly to their production and treatment to produce crudes for oil refinery processing.

Jan 1, 1951

By Corby G. Anderson, Caelen D. Anderson, Patrick R. Taylor

"The United States contains a variety of domestic rare earth element mineral sources containing such as ancylite, bastnasite, monazite, and xenotime. Research has been performed to investigate the fundamental surface chemistry involved in the froth flotation of these minerals, and apply the knowledge gained to substantiate the results through experimental testwork on a domestically sourced rare earth ore. This paper will outline the fundamentals and literature of rare earth mineral flotation, review its industrial applications and provide some recent research updates.THE RARE EARTH ELEMENTSRare earth elements (REE’s) are a unique family of elements with nearly identical physical and chemical properties. They account for approximately 1/6th of all naturally occurring elements, but the entire group occupies only one position on the periodic table. These 15 elements make up the lanthanide series (atomic numbers 57–71), and all but one (promethium) occur naturally. In addition to these 15 elements, yttrium and scandium are also considered rare earths since they tend to occur in the same deposits as the rare earths and share similar physical and chemical properties as seen in Figure 1. In particular Figure 2 denotes, a cartoon of the subtle differences in each caused by the 4f atomic sub shell (Gschneidner Jr., 1964). These subtle differences result in very difficult challenges in the selective concentration and final separation of each rare earth. (Anderson, 2015, Kronholm, Anderson, Taylor, 2013)Rare earths are separated into two different subsections; the “lights” or LREE’s (lanthanum57 through europium63) and the “heavies” or HREE’s (gadolinium64 through lutetium71). Yttrium is generally considered a heavy rare earth since its ionic radius is close to that of the HREE’s, while scandium is not considered either a light or a heavy."

Jan 1, 2016

By C. Rocha R.

Petioles is a mining group with integrated operations in the smelting and refining of non-ferrous metals, and is also a chemicals producer. Peñoles is the world&apos;s foremost producer of refined silver, metallic bismuth and sodium sulphate and is the leading Latin American producer of refined gold, lead and zinc. The Met-Mex Petioles Zinc Plant commenced operations in 1973 with an annual production capacity of 105,000 t/y. Year after year the production has been increased, and at present, the production capacity is 240,000 t/y. In this paper, the leaching process, particularly the operation of the jarosite circuit and its effective removal of impurities such as arsenic, antimony, indium, selenium and tellurium, is reviewed.

Jan 1, 2006

By Jan Butra

Longstanding mining of copper deposits in the Legnica-Glogow Mining Basin, Poland has accumulated broad experience concerning the impact of geological and mining conditions on seismic and rockburst hazard. Methods of rockburst prevention for deep copper mines have been developed based on gathered data. Methods of rockburst hazard evaluation and rockburst control constitute a set of rockburst prevention measures. Due to their nature and location within the production process, prevention methods can be passive or active. Active methods of rockburst prevention consist of the liquidation of stresses in the areas where they are concentrated through controlled generation of rock-mass tremors and rockburst by blasting works (group extraction blasting, release blasting in the rock mass and pillars able to accumulate the stress, as well as in the roof and floor). Group blasting works as a basic method are very effective in copper mine conditions. Provocation of dynamic events makes it possible to control the timing of their occurrence. In Polish copper mines, all blasting works are made during the absence of miners in the mining fields. Daily distribution of both the number of recorded strong seismic events and volume of energy released, confirm the advisability of using this kind of rockburst hazard prevention. The rockburst hazard prevention methods developed over 40 years of copper deposit extraction are economically reasonable and offer sufficient effectiveness under high rockburst hazard conditions.

Aug 1, 2013

By F. Andrieux

"Extruded aluminum profiles are increasingly used for lightweight vehicle construction. Since fracture strains of aluminum profiles are relatively low, damage modeling is crucial for reliable crash simulation. For aluminum profiles, not only the stress state but also the orientation influenced both the deformation and damage behavior. For the material characterization smooth tensile tests were performed in six orientations, both stress-strain curves and r-values were registered. Moreover notched tensile and shear-tension tests were performed in three directions. Finally punch specimens were tested to investigate biaxial loading. Digital image correlation (DIC) analyses were performed to determine local strain values such as critical values at failure. Numerical investigations were conducted with the strain based damage model GISSMO, which is well suited and widely applied for crash simulation. For a strain based failure model the choice of the deformation model is crucial. Deformation models with increasing complexity were investigated to find the best compromise over all experiments. It was found that there is still a great requirement on development of a material model which describes the orientation dependence of the hardening behavior over all stress states in order to be able to use a strain based failure model reliably.INTRODUCTION Weight reduction is an important step for less energy consumption and as a consequence aluminium is increasingly used in automotive parts. An important field of application is the well-established aluminium extrusion which allows the realisation of quite complex shapes of profiles required for an innovative lightweight design with integrated functions. Typical applications are chassis parts, bumpers, crash elements, air bags, etc. Especially the Al–Mg–Si medium strength alloys of the 6000 series can be easily extruded to form complex profiles and prevail for extrusion. Since fracture strains of aluminum profiles are relatively low, damage modeling is crucial for reliable crash simulation. For aluminum profiles not only the influence of the stress state but also the orientation with respect to the extrusion direction have an influence on both the deformation and damage behavior and need to be characterized. The effect of orientation on deformation behavior has been intensively investigated in the last decades and material models haves been proposed (e.g. Barlat & Lian, 1989; Barlat, Lege, & Brem, 1991; Barlat et al., 2003) to describe accurately anisotropic behavior. However it can be noticed that the parameters of anisotropic material models often rely on the yield stress in different directions, which means that the effect of strain hardening is not automatically accounted for. The accuracy of the models at large deformation is not guaranteed and has to be verified. In contrast to deformation models both the characterisation and the modeling of anisotropic damage behavior are not systematically studied. Isotropic failure models based on a critical strain as function of stress triaxiality (ratio of the hydrostatic stress to von Mises equivalent stress) are widely used for crash application (e.g., Bai & Wierzbicki, 2010; Sun, Andrieux & Feucht, 2009; Sun et al., 2013). The mechanisms of failure are manifold and not fully understood; to develop an anisotropic failure model it is mandatory to also have experimental data in different orientations for loading scenarios other than uniaxial tension, e. g. shear, biaxial tension, which implies an extensive experiment plan. This makes the development of failure models more challenging than deformation models for which it is possible to develop a reasonable anisotropic model using the framework of yield function and calibrate the material parameters based on results of tensile tests in different directions. Moreover the development of deformation and failure models are intricate as the variables governing the damage evolution are predicted by the def"

Jan 1, 2018

By C. Nikolic

A process utilizing ozone for the precipitation of cobalt from nickel sulphate liquors containing ammonium sulphate has been developed. Best results were obtained using nickel carbonate to maintain solution pH at 5.0 to 5.5. Work was performed both in column and stirred-tank reactors. Variables studied included neutralizer type and concentration, NH4+ concentration, temperature, Ni++ and Co++ concentration, per cent O3 in the O2 carrier gas, O3 input rate and agitation. The over-all rate of cobalt rejection increased sharply with increasing agitation and ozone concentration in the gas phase, reflecting relatively slow transfer of ozone from the gas to the liquid phase.

Jan 1, 1978

By J. F. Dorion

This paper presents the results of on-going investigations on the performance of support systems in Québec underground mines. The focus of these investigations is on site observations complemented by laboratory investigations. Of particular interest is deducing the corrosion rate, at selected mine sites, as determined by the installation of monitoring coupons.

May 1, 2009

By Radford B. Langston

Mining Methods Majority of Production Ramp and Fill at Stillwater, Sub-level Becoming More Important Production at East Boulder from Sub-level l Majority JM REEF ROCK TYPES NORITE - plagioclase and bronzite cumulate GABBRONORITE - plagioclase, augite, and bronzite cumulate TROCTOLITE - plagioclase and olivine cumulate ANORTHOSITE - plagioclase cumulate PERIDOTITE - olivine cumulate

May 1, 2002

By A. G. Darnley

"IntroductionTHE PURPOSE of this paper is twofold. Firstly, to drawn attention to recommendations which have been accepted by the International Atomic Energy Agency concerning radiometric reporting methods and calibration in uranium exploration, and secondly to emphasize the benefits that- will stem from adopting them. These recommendations are contained in an IAEA Technical Report, No. 174, which has been prepared with the intention of serving as a general guide to the subject. The existence of this specialized report is likely to be unknown to most of those who can benefit unless it is given some publicity by an organization such as the CIM. The recommendations were prepared by a small international committee consisting of Dr, P. H. Dodd , U.S .A. , Dr. R. L. Grasty. Canada, Dr. L. Levborg, Denmark, Dr. M. Matolin, Czechoslovakia , Dr. S. D. Simov, Bulgaria, and the writer.The fact that there are standard scientific units of mass, distance and time is taken for granted, It is also accepted that the type of instrumentation used to measure one of these parameters is irrelevant to the way the measurement is reported. Geophysical parameters such as magnetic field strength and gravity have generally accepted units, the gamma and milligal, which are defined in SI terms. These units are employed irrespective of the operating principle, or manufacturer or organization involved in the measurement."

Jan 1, 1977

By S. Khoshkhooei

In this research, the effects of rare earth elements addition on thermal fatigue behaviors of AZ91 alloy were studied. Repeated heating and cooling cycles were applied on the samples at 170°C and 210 °C to develop thermal fatigue cracks, Crack growth mechanisms and microstructural influences were investigated by optical and scanning electron microscopy (SEM) as well as energy dispersive X-ray spectroscopy (EDS), Thermal fatigue behaviors were improved successively by addition of up to 2-wt% RE, This improvement is attributed to consummation of the aluminum of the melt by precipitation of the needle shape Al 11 RE3 phases, This process reduces the volume of Mg17Al12 phases and consequently decreases the brittle Mg/Mg17Al12 interfaces which are the main reason of weak thermal properties of the alloy at rather high temperatures, Further additions of RE, however, reduced the thermal shock resistance of samples by increasing in the mean length of the brittle needle shape phases.

Jan 1, 2005

By S. Mathieu, R. Mennillod-Blondin, P. Cousin, N. Valle, H. Bouzahzah, P. Marion

The gold deposit of the Lapa mine has a complex mineralogical gold state with coarse and fine native gold, aurostibite and submicroscopic gold within arsenopyrite. A specific mineralogical characterization of the refractory fraction was conducted combining various techniques such as optical microscopy, electron microscopy, electron microprobe and secondary ion mass spectrometry. In parallel, the mineral processing behaviour and the recovery of the refractory gold were studied by pressure oxidation and cyanide leaching. This paper presents the mineralogical methodology developed to characterize the refractory gold distribution within arsenopyrite. These results are presented and interpreted in order to plot gold recovery versus sulphide oxidation. The comparison of the metallurgical behaviour yields predicted from the mineralogical data and the one calculated from leaching tests shows a good agreement and allows mineralogical explanations of the gold metallurgical behaviour.

Jan 1, 2011

By Maxime Tacher

BRP (Bombardier Recreational Products) designs and commercializes recreational vehicles such as watercrafts, sport boats, snowmobiles, ATVs... The Spyder roadster is the last product in the Can-Am product family lineup. To remain at the forefront of innovation, a hybrid motorization version of the Spyder is being developed in order to reduce fuel consumption and emission of greenhouse gases. But, the addition of electric components (e-motor, lithium-ion battery... ) raises the issue of added weight and volume. This article deals with the mass reduction of this Spyder by optimizing its frame.

Jan 1, 2011

By Jack Parker

"The original design of mine openings and pillars at White Pine was based upon traditional assumptions; i.e., that the principal load is due to the weight of overburden, and that horizontal stresses are equal to one-. third of the vertical.Beginning January, 1964, borehole deformation measurements confirmed suspicions that the principal stress is horizontal and several times greater than the vertical.Vertical stress appears to be directly related to depth, but lateral stresses vary considerably in direction and magnitude. The direction of major principal stress lies parallel to the bedding and is apparently parallel to tension joints. Lateral stresses appear to originate from an igneous intrusive.Mining induces stresses which add to the primitive stresses, in some areas precipitating failure. In this paper, rock failures are illustrated, methods of measurement and typical results are given, and measures to counter or utilize the lateral stresses are described."

Jan 1, 1966

By Ross G. Bertinshaw

"The Line Creek Mine of Crows Nest Resources started mining coal in the fall of 1981. There are seven mineable seams with thicknesses ranging from 1.5 to 13 metres and with dips varying from 0 degrees to 60 degrees. This, together with internal partings and the very friable nature of the coal, creates a number of mining problems.The coal is divided into zones depending on the dip of the seam. Each zone requires a different mining technique to ensure optimum recovery and low dilution while still keeping fines to a minimum.Line Creek employs a combination of hydraulic front shovels and backhoes to mine its coal without blasting or use of dozers. This has been very successful in reducing the proportion of fine coal hauled to the plant, thus improving quality control and reducing costs in coal processing.There have been a number of other benefits from the use of excavators instead of more conventional methods. These include better selectivity, good cleanup, reduction in traffic at the face and lower cost.IntroductionThe Line Creek Mine is situated approximately 25 km north of Sparwood in southeastern British Columbia (Fig. I). Preproduction stripping began in J98J with the first coal shipments made in 1982. In 1983 the mine produced 2.1 million tonnes of raw coal.Similar to other East Kootenay coals, the seams at Line Creek are characterized by their friability, producing a large proportion of fine coal during mining. In an attempt to reduce these fines Crows Nest Resources has instituted the use of hydraulic excavators to mine and load the coal.Hydraulic excavators offer other substantial advantages over front-end loaders and dozers, which has been the conventional system in other mines in the area."

Jan 1, 1985

By D. H. Flather, J. W. Hendry, K. Drover

Black Hawk Mining Inc. has completed a comprehensive program on the prediction and management of acid rock drainage (ARD) at their Keystone Gold Mine (Keystone) near Lynn Lake, Manitoba. The program, initiated in 1994, followed a phased approach utilizing initial acid-base accounting (ABA) results and subsequent laboratory kinetic testwork to define site-specific sulphide oxidation and neutralization consumption rates in waste rock. Net acid generating waste rock at Keystone was defined through the kinetic testwork as waste rock yielding a net potential ratio (NPR) of less than two. A preliminary waste rock management program based on blending of potentially acid generating and acid neutralizing waste rock was advanced. Subsequent refinement of the management program followed the analysis of over 1580 ABA samples collected from individual blast holes during the initial bench development phase of the Keystone pit. Uncertainties in actually achieving adequate blending within the dumps at a mining- scale resulted in the development of a revised waste rock management program based on segregation. Recognizing that any successful management plan requires that the ARD characteristics of the waste rock be identified prior to in-pit blasting, the extensive ABA database was utilized to develop a rapid characterization scheme. By implementing a characterization scheme based on total sulphur concentrations and fizz rating, waste rock could be quickly segregated without delaying the natural flow of ore from the pit. Interestingly, it also became apparent that gold values were strongly correlated with total sulphur, such that traditional fire assays were supplanted with a simple and more cost-effective total sulphur determination. The program highlights the importance and benefits of collecting and exploiting data beyond that necessary to acquire appropriate development permits.

Jan 1, 2000

By Marcondes Lima Costa

Abstract-The Amazon region is characterized by the development of deep chemical weathering represented by widespread lateritic covers and soils. Two distinct periods of laterite formation can be distinguished: mature laterites from the Eocene-Oligocene (and locally from the end of the Cretaceous), and immature laterites from the Pleistocene. The older laterites occur on plateau landscapes, and the younger ones on widespread hilly to flat lowlands. Both types show complete or truncated profiles, generally covered by deep yellow to brown topsoils. The mature laterite profiles contain high concentrations of gibbsite and/or aluminum phosphate, whereas the immature ones are poor in these minerals. The Amazon region is rich in mineral deposits related to lateritic profiles. Some mineral deposits are of primary origin but were concentrated to economic grades by lateritic processes. The most important ore deposits are of iron, aluminum (bauxite), kaolin, manganese, gold, nickel, copper and phosphate. These are mainly related to mature profiles. The wide spectrum of ore deposits and mineralogical and geochemical complexity of the Amazon laterites has been promoted by: (1) the prevalence of ideal conditions for laterite formation throughout much of the Tertiary; (2) the presence of varied basement lithologies due to contrasting geological environments; and (3) a variety of epigenetic alteration types. The lateritic profiles show a well-developed ore zonation which is related to specific lateritic horizons. Iron and gold deposits occur in the ferruginous horizon, which is nearest the surface; the central aluminous horizon hosts bauxites, aluminum phosphate, strontium and gold; and the lower clayey horizon contains deposits of manganese, nickel, copper and kaolin. Resistate phases which residually accumulate throughout entire profiles include titanium (as ilmenite and anatase), chromium (as chromite), tin (as cassiterite), yttrium (as xenotime), and niobium (mainly as ilmenorutile). Epigenetic alteration, caused by swamp environments developed above truncated lateritic profiles, has led to the formation of high-grade kaolin and refractory bauxites. The laterites in the Amazon region contain most of all known kinds of ore mineralization related to laterite processes.

Jan 1, 1997

By Marcondes Lima Costa

The Amazon region is characterized by the development of deep chemical weathering represented by widespread lateritic covers and soils. Two distinct periods of laterite formation can be distinguished: mature laterites from the Eocene-Oligocene (and locally from the end of the Cretaceous), and immature laterites from the Pleistocene. The older laterites occur on plateau landscapes,and the younger ones on widespread hilly to ?at lowlands. Both types show complete or truncated pro?les, generally covered by deep yellow to brown topsoils. The mature laterite pro?les contain high concentrations of gibbsite and/or aluminum phosphate, whereas the immature ones are poor in these minerals. The Amazon region is rich in mineral deposits related to lateritic pro?les. Some mineral deposits are of primary origin but were concentrated to economic grades by lateritic processes. The most important ore deposits are of iron, aluminum (bauxite), kaolin, manganese, gold, nickel, copper and phosphate. These are mainly related to mature pro?les. The wide spectrum of ore deposits and mineralogical and geochemical complexity of the Amazon laterites has been promoted by: (1) the prevalence of ideal conditions for laterite formation throughout much of the Tertiary; (2) the presence of varied basement lithologies due to contrasting geological environments; and (3) a variety of epi-genetic alteration types. The lateritic pro?les show a well-developed ore zonation which is related to speci?c lateritic horizons. Iron and gold deposits occur in the ferruginous horizon, which is nearest the surface; the central aluminous horizon hosts bauxites, aluminum phosphate, strontium and gold;and the lower clayey horizon contains deposits of manganese, nickel, copper and kaolin. Resistate phases which residually accumulate throughout entire pro?les include titanium (as ilmenite andanatase), chromium (as chromite), tin (as cassiterite), yttrium (as xenotime), and niobium (mainly asilmenorutile). Epigenetic alteration, caused by swamp environments developed above truncated lateritic pro?les, has led to the formation of high-grade kaolin and refractory bauxites. The laterites inthe Amazon region contain most of all known kinds of ore mineralization related to laterite processes.

Jan 1, 1997

Uranium mining remains controversial in many parts of the world, especially in a post-Fukushima context, and often in areas with significant uranium resources. Although nuclear proponents point to the relatively low carbon intensity of nuclear power compared to fossil fuels, opponents argue that this will be eroded in the future as ore grades decline and energy and greenhouse gas emissions (GGEs) intensity increases as a result. Invariably both sides fail to make use of the increasingly available data reported by existing uranium mines through sustainability reporting ? allowing a comprehensive assessment of recent trends in the energy and GGEs intensity of uranium production, as well as combining this with reported mineral resources to allow more comprehensive modelling of future energy and GGEs intensity. In this study, detailed data is reported for numerous uranium mines around the world, including production, energy and GGEs intensity and reported mineral resources. An important aspect included ? arguably unique and never before published ? is the relationship between ore grade and recovery, which is crucial in future projections of uranium mining. Overall, the paper shows the importance of continuing to improve reporting by the uranium sector as well as the ability to analyse key trends and future projections in energy and GGEs intensity of uranium production.

Aug 1, 2013

By S. B. Kang

Magnesium has poor ductility at temperatures lower than 225°C and, as a result, Mg alloy sheets are produced via fairly complex thermomechanical processes consisting of numerous sequential steps of hot (warm) rolling with low reduction and intermediate recrystallization annealing operations. In context of the present study, a simple technology for the fabrication of magnesium sheets by hot (warm) rolling was applied to various magnesium alloys. The misch metal addition in those AZ alloys was done to evaluate the deformation behavior. Tensile tests were carried out for those AZ alloys after applying different heat treatments. The precipitation of ß phase (Mg17Al12 phase) induced different microstructures with various cooling method from solution treatment temperature, and also with various annealing treatment temperatures.

Jan 1, 2006