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By G. G. Campbell

"HistoricalBARYTES was mined in Nova Scotia as early as 1874 from a deposit at Five Islands, on the north shore of Minas Basin. The first record of the presence of the mineral at the Walton site appears in a report by Selwyn in l893, who states: ""Barytes in considerable quantity occurs in veins in lime-stones at Walton and Pembroke"". The exact site of the present workings was marked •on a map published by Fletcher in 1905.The economic •possibilities of this deposit, however, were not recognized until 1940, at which time we were at war with Germany, who up to that time had supplied 50 per cent of the world's requirements.At that time the Nova Scotia Department of Mines, recognizing the need for certain strategic minerals, induced Canadian Industrial Minerals, Limited, to send prospectors into 'the area to look for manganese. No manganese deposits were found, but a deposit of barytes was directed to their attention, and exploration and development work on the occurrence was proceeded with.IntroductionThe south shore of Minas Basin between the Avon river at Windsor and the Stewiacke river at Maitland has long been known as a potential source of mineral wealth. It had attracted the attention of mineralogists and in the past had produced considerable tonnages of manganese ore and gypsum. Depletion of ore in surface and near surface deposits resulted in a dwindling production, until today only deposits of gypsum are worked."

Jan 1, 1952

The Bluebell mine of The Consolidated Mining and Smelting Company of Canada Limited extends under Kootenay lake, in southern British Columbia, and water control underground has always been a major problem. This paper gives a brief history of the operation, and then de-scribes the methods used by Cominco to keep the combination of lake seepage, ground water and thermal spring water under control. The pumping arrangements are de-scribed in considerable detail, with illustrations to show the various stages of development, and the power supply sys-tem is outlined.

Jan 1, 1966

By Ram Song, Yohei Harada, Shinji Kumai, Kazuho Otsuka

"Recently, vertical-type high-speed twin-roll casting (HSTRC) has been developed. The HSTRC shows extremely high cooling rates over 1,000 K/s even at the mid-thickness area. The fabricated strip has many metallurgical characteristics; super-saturation of alloying elements, fine solidified structure, and homogeneous distribution of fine constituent particles. In Al-Mn based alloys, the Mn alloying element can be supersaturated in the a-Al matrix and also form Mn-containing constituent particles during solidification. The Mn supersaturation and the distribution of primary/secondary particles in cast products affect the metallurgical behavior in the down-stream processing and can improve mechanical properties of the final products. In this study, Al-Mn based alloy strips were fabricated by HSTRC with various Mn contents. The solidified microstructure, constituent particles and its distribution, and Mn solubility were investigated in the as-cast condition. Due to the high cooling rate of HSTRC, fine constituent particles were homogeneously distributed, and coarse intermetallics were not observed. Mn solid solubility was estimated by electrical conductivity. The estimated Mn solubility was equivalent between strip surface and mid-thickness area.INTRODUCTION Al-Mn based alloys, as non-heat treatable wrought aluminum alloys, are widely used in packaging and heat exchanger for automobile industry. Besides Mn, Al-Mn based alloys often contain Fe and/or Si as alloying elements or natural impurities. During solidification, Mn can be super-saturated in the Al matrix, and also form Mn-containing constituent particles. Additionally, in the subsequent thermal-mechanical processes such as homogenization, rolling, and intermediate annealing, Mn in solid solution precipitates out of the Al matrix as secondary particles. The size, distribution, type, and the amount of dispersoids including constituent particles affect to texture evolution, recrystallization behavior, and final mechanical properties of wrought Al-Mn based alloys (Huang et al., 2016; Huang & Marthinsen, 2015; Engler et al., 1995; Muggerud et al., 2013). Therefore, controlling the initial level of Mn super-saturation and the distribution of constituent particles are important in the cast Al-Mn based alloys."

Jan 1, 2018

By A. Kraly, M. Complojer, P. Paschen, K. Gamweger, H. Antrekowitsch

Increasing quality of aluminium alloys and continuous optimization of the production process leads to an improvement of the gas purging systems. The application of porous plugs for the treatment of liquid aluminum is nowadays not widely used in the aluminium industry especially in Europe. The Department of Nonferrous Metallurgy and the Christian Doppler Laboratory of Secondary Metallurgy of Nonferrous Metals intensified the research and development of refining and alloying processes by gas treatment during the last years. CFD-modeling supports these experiments, which should lead to lower hydrogen content, lower suspended particles and a better distribution of alloying elements in the melt. Different parameters such as temperature, bubble size, gas amount and which kind of gas is used influence the quality of the products.

Jan 1, 2006

By E. G. Baltuch

Natural Ventilation in mining and metallurgical processing applications is key to proper operation function. There are number of ventilator designs available to a project team or design engineers, the selection of which will affect both the type of building structure required, project costs and design performance which is difficult to rectify or re-engineer once implemented. Research and applied results, such as that performed by Air-Therm Inc., demonstrates that computational fluid dynamic simulation allows for 5 dimensional observation, analysis and optimization at significantly lowered cost than previously possible. These results have been fully implemented on a number of mining and metallurgical applications and the company continues to study, optimize and innovate as new tools become available to provide the best possible engineered solutions for particular applications.

Aug 1, 2013

By D. C. McKechnie

To the examining engineer, the ever-recurring problem involving the valuation of ore in a prospect presents at different times highly divergent aspects- some entirely physical or mathematical, others essentially personal. The majority of the problems discussed in this paper are obvious to the engineer, and need little elaboration. By the prospector and the general public, however, a number of these questions are often and completely over-looked, or else approached in such a way as to produce final results which are, to say the least, misleading and at times decidedly erroneous. While the purpose of this paper is to deal with prospects or potential mines, many of the problems considered apply equally well to mines with developed ore reserves. As the usual showings on a prospect consist chiefly of a few open-cuts and a limited amount of underground development work, an estimation of the actual ore reserves is a question of minor import, and seldom enters appreciably into an estimation of the probable value of the particular property. The physical valuation of a prospect mainly involves the consideration of such subjects as the general geological features exposed, the strength and type of mineralization, the width and persistence of any associated veins, shear zones, fractures or contact zones, together with the possible grade, size, and continuity of any ore-bodies that may there occur.

Jan 1, 1930

By J. Kronsteiner, E. Kabliman

"In the present work, we developed a Smart Process Control Toolkit (SProC) as a single simulation environment for the modelling of materials microstructure and its interaction with the local microchemistry during manufacturing of semi-finished products. This toolkit supports the data communication between sub-sequent processing steps such as casting, homogenization, pre-heating to deformation, etc. The thermo-kinetical simulation software MatCalc of MatCalc Engineering© GmbH was used for modelling of precipitation kinetics, such as formation of primary and secondary phases and their evolution. An import/export functionality of the precipitation distribution after each processing step was implemented to follow the parameter history. For the evolution of the local microstructure, a Mean Dislocation Density based Model (MD2M) was used. This model consists of two parts: (1) Flow Stress Model for calculation of the total strength during the deformation and (2) Static Recrystallization Model for account of the recrystallization and grain growth after the deformation. Validation was done by a comparison of experimental and simulated hot compression tests of a conventional AA2024 alloy.INTRODUCTION Optimization of a semi-finished products quality, elimination of typical production issues and cost savings are of a great demand for supply industries. However, it is currently not feasible to investigate the whole manufacturing process in detail at an industrial level. Concerning the processing parameters, one must understand the correlation mechanisms between macroscopic properties and microscopic material behavior. Numerical simulations, which could reproduce the real processing conditions on the one hand, and employ a physically based modelling on the other, are thus attracting a lot of attention and their power is no longer under the question. It is well known that e.g. the total strength of the material depends directly on distribution of precipitation particles and mean grain size. In order to follow their evolution during the manufacturing process beginning from casting to the final semi-finished product, and thus be able to control the process, one should use the techniques which would at the same time reproduce experimental processing conditions of real size objects (e.g. sheet, extrusions, etc.) and account for the evolution of a local microstructure and its interaction with the microchemistry. A commonly used approach is to implement a model which would describe the evolution of microstructure based on a dislocation density approach into a user defined material subroutine of some finite element solver. There is, however, also an influence of the manufacturing process by e.g. the evolution of a local microchemistry (formation, transformation and dissolution of the precipitation particles) on the microstructure and thus the macroscopic material behavior. Thus, a method is needed to follow the variable history through the simulation of the whole production chain."

Jan 1, 2018

By CRO CRO

Elk Valley Coal?s Cheviot Project is located in the Alberta foothills south of the town of Hinton. The mine has been in operation now for the 3 years. The start up and subsequent operation of the Cheviot project has been directly influenced by the Cardinal River Mine. As the Cardinal River Mine was winding down due to reserve depletion in 2004, the price of seaborne traded metallurgical coal jumped to record levels and customers began aggressively seeking new sources of supply. Several months later, the owners of Elk Valley Coal decided to begin mining at the Cheviot mining area, extending the life of the area?s operations by over 25 years. The Cheviot Project had been delayed by low coal prices, ownership changes and a complicated and lengthy regulatory process fueled in large measure by stiff opposition from a number of major environmental organizations. Chief to the startup of the project was the construction of a 23-kilometer-long haul road that would connect the new coal measures to the existing Cardinal River processing and rail facilities. Construction of this road was completed with the first coal truck making its first trip in October 2004. This paper will look at some of original assumptions, the actual mining experiences and the lessons that were learned while moving from the drawing board to the current development as it exists today.

May 1, 2007

By S. Lun Sin

In this study, the effect of silicon on the microstructure, mechanical properties and hot tearing susceptibility of permanent mould cast AZ91E magnesium alloy was investigated. Varying amounts of silicon (0.5, 1.0 and 1.5 wt.%) were added to AZ91E in the form of an Al-53 wt.% Si master alloy. The phase formation, grain size and solidification behavior of each alloy were characterized and related to their tensile properties and hot tearing susceptibility. The results showed that the addition of silicon resulted in the formation of Mg2Si particles. The presence of these particles led to an increase of the hardness, but was detrimental to the tensile strength and elongation of AZ91E. However, silicon significantly reduced the hot tearing susceptibility of AZ91E. This was attributed to the reduction of the grain size and the decreased freezing range of AZ91E, which contributed to improve the interdendritic feeding during the last stage of solidification.

Jan 1, 2011

By J. Bardinas

"The use of autogenous mills has become widespread, owing to their capacity and favorable capital and operating costs. Optimal operation of these systems is critical, given their high energy consumption and effect on downstream processing. A considerable effort has been spent over the years in the development of advanced control systems to achieve a better performance in this regard. However, despite significant advances, the problem still remains challenging, owing to the nonlinear behaviour of the system with respect to the mill variables, and, the unmeasured ore variability come from the mine.The mill load, in particular, can be seen as a state variable of the mill, which could be important for; modelling and control, and, important insights into the mill behaviour. In this investigation, time series cluster analysis was performed using online mill load measurements in order to identify the different control states of the mill. More specifically, this time series was divided into short non-overlapping segments. A distance matrix was set up for each segment and the information was captured by means of textural features, similar to that used in multivariate image analysis. These wavelet and grey level cooccurrence matrix features could subsequently be used to rapidly identify the normal operating conditions from the feed disturbances in the mill.In principle, the methods and models presented here, once suitably validated and calibrated, could be used in online process monitoring of autogenous mills. They also could serve as a foundation for developing more advanced process control models."

Jan 1, 2016

By M. Kamyab

The Deep Exploration Technology project, as part of the Australian Cooperative Research Centre, is developing technologies to drill deep boreholes for mineral exploration purposes. The aim of the initiative is to transfer drilling technologies from oil and gas into mining applications. Several modifications have to be pondered due to this technology exchange: smaller cuttings sizes because of using impregnated diamond bits; narrower annulus space; higher drilling fluid velocity and likelihood of turbulent flow regime in the annulus; and higher pressure loss. In particular the results of our lab experiments have shown that the increase in concentration of small size cuttings can significantly change the rheology of the mud when drilling in hard rocks. This, in return, could have a noticeable increase in the pressure loss encountered along the annulus space. As a continuation of the above study, numerical simulations were conducted to investigate the cuttings transport behaviour in small size annulus space. Fluid velocity, annulus size, cuttings concentration, cuttings density, and cuttings size were some of the parameters that were varied to see their effects on cuttings transportation and the pressure loss along the annulus space. The results indicate that, due to the differences between oil and gas and mining drilling, conventional oil well planning is not applicable for mineral exploration drilling and numerical simulation would help in this matter.

Aug 1, 2013

By D. D. Campbell

"The Port Radium mine of Eldorado Mining and Refining Limited lies on the western tip of a large peninsula midway up the east shore of McTavish Arm, Great Bear Lake, about 30 miles south of the Arctic Circle. The mine is serviced by air, 950 miles from Edmonton, and by water, 1,380 miles from Waterways, Alberta.The veins were found, and the copper and cobalt minerals in them reported, by J. MacJntosh Bell of the Geological Survey of Canada in 1899. The veins were investigated by Gilbert Labine and E. C. St. Paul in 1930, and as a result of their work the Eldorado mine was brought into production in 1934. It produced silver and radium ores until 1940, at which time, as the silver orebodies had been mined out and the market for radium was negligible, it closed down. Early in World War II the need for uranium for the Manhattan Project was emphasized, and the mine was reopened in 1942. As a security measure Eldorado Mining and Refining was created a Crown company in 1944. The Port Radium mine has continued to be one of Canada's principal producers of pitchblende concentrates, and to date has about 25 miles of underground workings developed on fourteen levels.Regional GeologyThe general geology of the McTavish Arm area was mapped by D. F. Kidd in 1932 on a scale of one inch to four miles. A great deal of more detailed work has since been done by geologists of the Geological Survey and of Eldorado. The entire area at the end of McTavish Arm lies within the Precambrian Shield immediately east of its western margin. Most of the area is underlain by granitic masses which have intruded a sequence of late Precambrian sediments, volcanics, and hypabyssal intrusives. The pre-granite rocks now occur in extensive, irregular patches and pendants within the granite. Pitchblende deposits have been found in the district in all rock types, but the most favourable host rocks are the cherty sediments of the lower Echo Bay group."

Jan 1, 1949

Productivity and efficiency of diesel-powered underground trucks and LHDs can be enhanced through the application of a range of advanced technologies. In addition, these machines are subject to ever more stringent emissions control requirements. This paper will review how various technologies can improve usability, maintainability, and performance of LHDs, through a number of examples. The use of instrumentation and monitoring to understand the role of operator practice on mucking efficiency, as well as the use of finite-element analysis to evaluate structural design, and the use of control techniques to modify operator inputs and hence decrease power consumption, will be presented.

May 1, 2002

By S. A. Ghoreishi-Madiseh

Underground mines, with their relatively high ground temperature and their extensive backfilled stopes provide a great opportunity for producing geothermal heat. The novel idea of installing a network of heat exchange tubes into stopes prior to backfill placement converts each mine stope into a heat producing battery. In this system, backfill plays the role of the heat exchange medium conducting heat from the surrounding rockwalls to the heat exchange tubes. This geothermal heat can be used for heating: mine facilities and buildings, the intake air, a close-by mineral processing plant, or even nearby communities. This paper investigates the possibility of extracting renewable geothermal energy from backfilled mine stopes by means of closed-loop geothermal cycles. To simulate realistic operational conditions a heat transfer model is developed and solved numerically. To evaluate the numerical results, a small scale physical model is constructed and the experimental results are compared with the simulation results. The study estimates the sustainable rate at which heat can be extracted from a typical underground mine stope, the resulting outlet temperature and performance of the geothermal system. The results show that mine stopes are capable of sustainably producing geothermal heat not only when the mine is active, but also after the depletion of the ore body. Therefore, an underground mine will no longer be perceived as an enduring economic liability, but as a long-lasting source of clean, renewable, and inexpensive low-grade geothermal heat.

Aug 1, 2013

By W. E. Bawden

Situation: Creighton mine, situated about twelve miles west of Sudbury, Ont., on the Algoma Eastern railway, is owned and operated by the International Nickel Company, incorporated in the United States under the laws of New Jersey. The ore is smelted at Copper Cliff, near Sudbury, and the matte is refined at Port Colborne, Ont., on lake Erie. Geology: The ore occurs in what is known locally as 'the basin' near Sudbury (Figure 1) the central part of which is composed of the Animikie series of sediments, consisting of sandstones, slates, tuffs and conglomerates. The basin is about 16 miles wide and 36 miles long. The Animikie sediments are surrounded by a sill of norite - a gabbro rock in which the pyroxenes are orthorombic. On the outer contact of this norite the sulphide deposits occur and the Creighton deposit, similar to others, lies on the southern edge of this basin. There are two orebodies at the Creighton, the upper one called the footwall orebôdy, and the lower one the hanging-wall orebody. The hanging-wall of both of these bodies is norite, and the footwall of the upper one is granite. The two are separated by an intrusion of greenstone which forms the footwall of the lower body. The ? maximum length of the deposit is 1000 feet and the maximum width is approximately 300 feet. It narrows at the ends and is somewhat lenticular in shape. The dip is about 45 o to the west, and the strike is north and south. The orè is a mixture of three minerals - pyrrhotite, chalcopyrite and pentlandite. The pentlandite, which is distinguished by its cleavage from the other two, is apparent to the naked eye only in the lower orebody and is more finely disseminated in the upper one. The lower body contains a little higher percentage of nickel.

Jan 1, 1925

By D. B. Johnson

Acidic, metal-rich waters generated at working metal mines and abandoned mine sites are generally considered to be major pollutants of the environment. However, the metals they contain often have significant value of their own, or as sources of useful mineral products. We have developed novel bioreactor systems that facilitate the selective recovery of various transition metals (e.g. copper, zinc and iron) as defined minerals that can be recovered and recycled. The bioreactors use novel species of acidophilic bacteria. Ferrous iron is oxidised by Ferrovum myxofaciens, a specialist bacterium that forms large amounts of exopolymers and grows as filamentous streamers in flowing mine waters, and the ferric iron generated is precipitated as the mineral schwertmannite, a small proportion of which is used to remove any arsenic present in mine water. Copper and zinc are precipitated as sulphides using H2S generated by consortia of acidophilic and acid-tolerant sulphate-reducing bacteria in a continuous flow, on-line low pH bioreactor. Transition metal sulfides can be segregated by precipitating them, either on-line or off-line, at different pH values. The modular units that have been developed can be configured to treat mine waters of different chemistries. A hypothetical acidic (pH 2.5) mine water stream containing 500 mg/L iron, 100 mg/L of copper and zinc, 50 mg/L of aluminum and manganese, 2 mg/L of arsenate, and discharged at a rate of 10 L/s, is used as an example of the potential application of the mineral-generating bioreactors. The environmental benefits and economic implications of considering mine waters as resources rather than wastes are discussed.

Aug 1, 2013

"A growing public awareness of work-related diseases such as pneumoconiosis and the impact of this awareness on legislative bodies and on the skilled labour market are reasons why the Canadian mining industry must consider dust control of top-drawer importance. Measurements and standards related to the hazard are necessary to control a dust situation and to avoid excessive risk. The author discusses some of the methods of measurement, standards proposed and terminology used in this developing technology. The purpose primarily is to give a better understanding of the basic advances achieved by those who have applied current knowledge with a measure of success."

Jan 1, 1972

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 M. Mahdi Aboutalebi, Roderick I. L. Guthrie, Mihaiela Isac

"A preliminary computational fluid flow model has been developed to simulate the flow field of liquid steel in the mold region of billet mold casting. This study reports the effect of different Submerged Entry Nozzles (SEN) on the fluid flow in round and square billet, curved mold, casters. In this study, ANSYS Fluent 14.5 software was used to model the 3-D turbulent flow of liquid steel. The standard k-0 model was used to simulate turbulence in the mold region. Similarly, the species transport equations were discretized to simulate the dye injection test into the mold cavity. The behavior of flow in the mold region was validated against previous experimental work. Predicted results showed that different nozzle types plus the slight curvatures in the molds can significantly influence the flow patterns generated within the mold region, and thereby affect the finished quality of the billet products.INTRODUCTIONConventional Continuous Casting (C.C) processes are presently used to solidify more than 95% of the 1.5 billion tons of steel now produced in the world annually (World Steel in Figure, 2014). This overwhelming contribution of C.C processes for steel production is the prime motivation for this study, in order to understand and optimize the casting processes and thereby reduce internal defects and minimize energy consumption. The primary objective of all C.C processes is to maintain liquid metal purity during the casting process and to create a uniform flow within the caster so as to avoid internal and external defects. In this regard, studying fluid flows in the mold region of continuous caster has attracted many research groups, in both academia and industry, in recent years. The mold region is one of the most critical parts of the C.C. process, in which the transport phenomena associated with this region can significantly affect the quality of the final products. Thus, proper control of fluid flows within this region can be expected to greatly decrease both internal and surface defects such as Oscillation Marks (OM), inclusion entrapment, and Mold Powder Entrapment (MPE). In the casting process, the fluid flow in the mold region can be affected by a number of variables, such as; the flow control system (stopper rod or slide gate), nozzle geometry, SEN (Submerged Entry Nozzle) depth, casting speed, mold dimensions, gas injection, and the application of electromagnetic fields. One of the most influential and easily-changed fluid flows are the jets of steel issuing from the SEN. Nozzle geometries are variable, consisting of a number of exit ports, different port angles, and/or port sizes, the bottom shape of the nozzle, and the SEN immersion depth (Thomas, 2001). The SEN characteristics can markedly affect meniscus surface velocities, surface level profiles, and turbulence levels that can vary in terms of the frequency and the magnitude of their fluctuations."

Jan 1, 2016

By C. E. St. Denis

"Training Program at Sherritt Gordon's Ruttar:. ConcentratorA formal training program for mill operators is being developed and employed at Sherritt Gordon's Ruttan Concentrator. The program was set up to fulfil the needs created by a shortage of skilled reliable labour, a 200% turnover of personnel within the first six months of operation and the rapid advances in mineral processing technology. All new employees are introduced into the Mill Department through an orientation program designed to familiarize them with the operation of the plant. All training and orientation of new employees is the responsibility of a. small training section consisting of two training foremen and one assistant. Using a combination of classroom and supervised on the job training, the training times have been cut by at least one half. High operating standards have been set and are maintained through the use of detailed manuals for each work area and competent instruction at all operating levels. The major portion of training costs arise from the salaries of the training staff but are negligible when compared to the improved recoveries, smaller turnover and less downtime. Government assistance is available to all industrial employers to offset the costs of training employees."

Jan 1, 1974