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By Jacek Paraszczak

Application of teleoperated and automated mobile equipment in underground metal mines represents a promising avenue to overcome some of the challenges facing the industry. This paper addresses the issues of overall effectiveness of the autonomous loading and haulage equipment in comparison with conventional man-operated machines. It overviews and discusses the factors affecting availability, utilization and production rate. It puts an emphasis on some problems and risks not present in conventional man-operated systems, as well as their character and criticality. It stresses the need to analyze the factors affecting OEE of the autonomous equipment more in-depth than it has been done up to date and to take them into consideration at the stage of feasibility studies. The paper concludes with some recommendations and indicates the directions of the future research in this field.

Oct 1, 2009

By S. Srinivasan, R. Coté

"India is undergoing a massive electrification program using local coal to provide fuel for thermal generating plants. The Rajmahal mine in northern Bihar is scheduled to produce coal at the rate of 10 million tonnes per year by the end ofa sixty six month contract with MET-CHEM Canada Inc. for mine development. In order to control maintenance performance and warehouse inventory MET-CHEM is installing some proven computer-controlled programs and will provide extensive training to ensure that the systems are properly used. The programs are Maintenance Planning and Control System (MPCS) and Materials Management System (MMS), both of which were developed and used by Quebec Cartier Mining Company at its iron ore mine in northern Quebec. In addition, a Predictive Maintenance Program (PMP) using vibration analysis will be introduced . This paper discusses the three systems.IntroductionIndia is currently undergoing a massive countrywide industrialization and electrification program. Most of the power will be supplied by coal-fired thermal electric plants.One of the mines being developed as part of the over-all program is the Rajmahal Open Cast Coal project in the Godda District of Bihar, approximately 270 km north , and slightly west of Calcutta.The project is based on an agreement signed in January, 1989 between two government organizations - Canadian Commercial Corporation (Ccq and Coal India Limited (CIL). MET-CHEM Canada Inc. (MET-CHEM), an international consulting engineering organization which has worked in India since 1976, is CCCs Canadian executing agency for the project. METCHEM was the engineer-constructor and mining associate for the development of the 7.5 mtpy Kudremukh Iron Ore Project. This US$430 million project was completed on schedule and under the original budget estimate. The Rajmahal deposit is the responsibility of Eastern Coalfields Limited (ECL), a subsidiary of CIL. The project is to produce coal at the rate of 10.5 million tonnes per year in 1994."

Jan 1, 1991

By L. Heber Cole

In making this plea for a better and more sympathetic understanding of the non-metallic industry, I do not for one minute wish to give the impression that I in any way belittle the wonderful strides that have been made in the exploitation of our metallics. We in Canada can be justly proud of our Sudburys, Norandas, Flin Fions, and of the remarkable growth of the Consolidated in British Columbia, and at the same time, without in the !east detracting from these worthy undertakings, be equally as proud of our asbestos, gypsum, salt, and coal deposits, as well as of our building-stone and limestone industries. If, in my remarks, I have occasion to compare the metallic with the non-metallic industry, I do so, not with any idea of dimming the glory which the metallics of Canada have gained- not only in our own country, but in the world at large-but for the purpose? of bringing to your attention the fact, perhaps not very well recognized, that Canada contains deposits of non-metallics well worth y of your serious consideration. In the past 33 years, namely, since 1895, the value of non-metallics produced in Canada has exceeded the value of metallics in 19 of the years, and for the last three years has been increasing rapidly. The war years (1915-1918 inclusive) naturally saw an intensive metallic production, but since that time, with the exception of 1925, when there was a general depression throughout the whole country, the non-metallics have been in the ascendency.

Jan 1, 1929

By J. Bensabat, B. Figueiredo, A. Niemi, J. Rutqvist, C. F. Tsang

"A hydro-mechanical model was developed to study the interaction between mechanical deformation and fluid flow in the fault zones during CO2 injection and storage at the Heletz site which was chosen as a test site for CO2 injection experiments in the framework of the EU-MUSTANG project. The potential reservoir for CO2 storage at the Heletz site consists of three sand layers separated by lowpermeability shale layers. The potential consequences caused by fault reactivation, focusing on the shortterm integrity of CO2 storage, are evaluated. The difference in the results obtained by considering the three-layer as an equivalent layer storage formation is analyzed.INTRODUCTIONLarge-scale storage of CO2 in deep underground reservoirs may cause considerable pore-pressure perturbation as well as flux migration and concern has been raised over whether shear slip displacements may be induced in nearby faults, as a consequence of their reactivation. A state-of-the-art review can be found in Rutqvist (2012), which describes the various possible effects resulting from CO2 injection into a deep sedimentary basin, including those involved in reservoir stress–strain changes, micro-seismicity, caprock sealing performance, and potential fault reactivation. Moreover, several studies have recently shown how CO2 injection may produce seismic events both on major faults (i.e., large faults with large initial shear offset) (Cappa & Rutqvist, 2011a, b, 2012), and on minor faults that might have gone undetected during the site characterization, e.g., faults less than 1 km long and without detected initial offset (Mazzoldi et al., 2012).The present paper is concerned with the Heletz formation which was chosen as a test site for CO2 injection experiments in the framework of the EU-MUSTANG project. The Heletz site located at the southern Mediterranean coastal plain of Israel and the structure is an anticline fold with a crest of about 4 km by 2 km. The structure is gently dipping to the east, truncated by a pinch-out line to the west and subdivided into a number of blocks by transversal normal faults with small displacements. The water table is located at 300 m below the land surface. An areal sketch of the site with the elevation of the caprock and the location of the borehole that has been chosen for the CO2 injection experiment is presented in Figure 1."

Jan 1, 2015

By A. Alwasel

Musculoskeletal disorders (MSDs) threaten the wellbeing and livelihood of a large number of construction workers incurring a significant cost to society. We present a new method to monitor and diagnose MSD risks in the workplace. The sensing unit of the system is an optical encoder encompassed within a non-intrusive exoskeleton to measure the joint angle of interest. This sensor can be applied to ball-and-socket and hinge-type joints of the human body, such as the shoulder, elbow, and knee joints. The system is contactless and does not require markers or cameras. Angle measurements are acquired directly without mathematical post-processing, thereby avoiding numerical noise and drift challenges. The system is a simple, robust, and deployable, but it currently lacks resolution of parallel degrees of freedom.

Aug 1, 2013

By L. Voisin, E. Díaz, V. Montenegro, W. Kracht

Grinding media is of great concern in the mining industry mainly because its consumption represents an important part of the costs during mineral processing and consequently, of the total mining business OPEX. In addition, grinding media consumption impacts directly on flotation performance through negative contamination by corrosion, affecting the pulp chemical potential, complicating the understanding and control of the process, as galvanic interactions between mineral species also occur. In addition, during the process there is also a physical consumption of the grinding media through erosion and impact. In both cases, mineralogy has an important role because pulp abrasion power, chemical reactivity, rheology, hardness and other variables depend on the minerals contained in the pulp and their interactions. In the present study, a geometallurgical and phenomenological model, which describes the grinding media consumption and its relationship with mineral hardness expressed by Bond Work Index, was obtained based on advanced mineral characterization techniques such as Hylogger3TM, X-ray diffraction, X-ray fluorescence and experimental grinding tests using a laboratory mill applied on Chilean copper pulps. The results obtained show that pH has an important effect on grinding media consumption, because corrosion varies with hydrogen ions availability. Also, mineral hardness depends on mineralogical composition, but textural analysis must be performed to have a better description of this property. Finally, minerals present in a sample define the grinding media consumption mechanism, because a sample with harder minerals and a greater value of Bond Work index is capable of protecting grinding media from impact wear, while a sample with lower hardness but with a big sulfide minerals content would be more aggressive with grinding media because corrosion is more important in this case. The geometallurgical model obtained is capable to relate the grinding time, mineral hardness, content of sulfide minerals and grinding pH to estimate the grinding media consumption.

Jan 1, 2017

By Philippe Poirier

Les parcs à résidus miniers représentent un risque environnemental qui nécessite une gestion adéquate. Suite à la publication du « Guide sur la gestion des parcs à résidus miniers » en septembre 1998, les membres de l?industrie minière ont appliqué les éléments de gestion du Guide, permettant ainsi une amélioration continue des opérations. En février 2000, l?industrie minière a indiqué le besoin d?établir des lignes directives plus spécifiques pour l?opération sécuritaire des parcs à résidus. Dans cette optique, l?Association Minière Canadienne a publié, en septembre 2002, un Guide pour l?exploitation, l?entretien et la surveillance (EES) des parcs à résidus miniers. Suite au développement du Guide et à son application sur plusieurs sites miniers, il apparaît que la mise en oeuvre d?un Manuel ESS des parcs à résidus miniers permet : ? d?établir les responsabilités des intervenants; ? de s?assurer que les critères d?opération sont appliqués; ? de mettre en oeuvre le plan de déposition des résidus et de gestion de l?eau; ? de rencontrer les normes et exigences environnementales; ? de définir un programme d?entretien et de surveillance des ouvrages; ? d?identifier les risques et de mettre en oeuvre un plan d?intervention d?urgence; de démontrer une opération diligente.

Nov 1, 2002

By L. A. Gomieroa

The Caetité-Brazil uranium facilities produce about 340 t/y of uranium from an ore averaging 0,25 U %. The process steps are ore crushing, heap leaching with sulfuric acid, U separation and purification by solvent extraction with tertiary amine followed by stripping with sodium chloride solution and precipitation as ammonium diuranate that is dryed. A change in the milling process is being evaluated to increase the production and the uranium recovery. Heap leaching will be changed to conventional tank agitated leaching of the ?590 ground ore slurry in sulfuric acid medium. The replacement of the stripping reagent is also being considered.

Aug 1, 2010

By Raymond D. Potts

"Minntac is a taconite mining, concentrating and pelletizing operation located near the town of Mountain Iron, Minnesota, U.S.A. It is totally owned and operated by USX Corporation and represents its largest source of domestic iron units. Minntac began producing fluxed pellets in 1988 and has produced both acid and fluxed pellets since then. This paper compares the acid and fluxed pellets produced at Minntac. It reviews modifications that have been made to the plant flowsheet and discusses areas recognized for improvement since the beginning of fluxed pellet production. It also comments briefly on the performance of Minntac fluxed pellets in USX blast furnaces and the future of fluxed pellets at Minntac.IntroductionMinntac was built in three steps with each step designed to produce 6 million long tons of acid pellets per year. The actual production has varied though. Figure I shows the production by year at Mirmtac. Step I began production in 1967, Step 2 in 1972 and Step 3 in 1978. Mirmtac produced 16.5 million tons in 1979 but only 3.5 million tons in 1982 when the facility was shut down for six months because of the lack of demand for pellets. Since the initial start up, Mirmtac has produced over 200 million long tons of pellets. Until 1987, all the pellets produced were ""acid"" pellets. In 1987, equipment to produce ""fluxed"" pellets was installed and tested. In 1988, full scale production of fluxed pellets began."

Jan 1, 1991

By Xiao Huang, Dongmei Wang, Prakash Patnaik

Further increase in gas turbine engine temperature necessitates continuous development and advancement to thermal barrier coatings. While tremendous effort has been devoted to developing new thermal barrier coating materials and processing methods in order to decrease the thermal conductivity, limited attention has been paid to radiative thermal transport through coatings. It is the purpose of this study to develop a new layered coating structure that can be used to effectively reduce the both radiative thermal transport as well as thermal conductivity, and to demonstrate the mechanism and effectiveness of the proposed multilayered structure. Mathematical modeling based on the multilayer quarterwave stack and simulation results are presented.

Jan 1, 2004

By Robert G. Boutilier

Mining companies in communities without other large employers often encounter dependent or defiant stakeholder attitudes, sometimes simultaneously. Less often they also see some slip into social dissipation or advance towards sustainable development. This paper presents a four-quadrant framework that shows how patterns of social capital foster these four reactions. The two dimensions defining the quadrants are the social capital levels (a) between the company and each stakeholder, and (b) among stakeholders themselves. Examples from the Antamina mine in Peru illustrate a social capital measurement system that can predict these reactions and help the community chart its path towards sustainable development.

May 1, 2006

By Md. Rashedul Islam

Magnetic data was collected from the Yeoju historical sites using the fluxgate gradiometer through six sites & several grids. We measured the vertical gradient by the FM256 Fluxgate gradiometer. The readings were logged every half meter. The obtained data were processed and treated to introduce a high quality magnetic image. The gradiometer results defined various positive and negative magnetic anomalies, which revealed the existence of several archaeological features of different shapes and sizes. The study of the process magnetic images give us a concept that the subsurface features are caved shape stone chamber tombs, burial mounds, deep room structure, Yeoju mausoleum, pagoda?s square foundation stones, walls etc. All these are superior work of early Goguryeo inheriting orthodox Silla style. So, the study area may have great archeological interest.

May 1, 2009

By J. C. Loretto

"OPENING REMARKS Yesterday and today we have heard some very interesting papers on operating matters and some of you are probably wondering what we are now doing talking about Communications in Plant Design. Let me tell you! Before the techniques we have heard being discussed can be used, there has to be a properly operating plant. It is certainly a fact that many mineral processing plants achieve only limited success and a number of them can even be said to be failures. Some of you sitting here are probably living with operating problems that are clue to errors in the design.If the histories of these problem plants are examined, it will be found that in many cases, the necessary skills were available during the period of the plant design. There was extensive operating know¬ledge together with a full range of project expertise. Why then the failures? In a substantial number of cases it can be traced to the old, old problem of communications. As plants get bigger, money costs more and smooth startups become more important, it becomes less and less economic to fix up any design errors during plant operations.During our careers in mineral processing, nearly all of us will be involved in at least one plant design and I feel that it is as well if we understand some of these communication difficulties that can lead to a problem plant. There is little point in us being experts in mineral processing if the knowledge we have acquired doesn't somehow get incorporated into the plant.I would, therefore, like to present this short paper that mentions a few of the significant communication problems that can occur during the design of mining and mineral processing plants, together with some thoughts on answers to these problems."

Jan 1, 1973

By C. L. Monroe

It has been the custom in recent years to look upon Atlin as a worked-out placer camp. This is a conception, however, which is far from the real situation. The placer-gold deposits of Atlin are today, after thirty-one years of continuous working, a field well worth the attention of the mining world. It is true that the shallow diggings (the 'easy money') have been practically cleaned out, but although there have been perhaps ten millions, or more, in gold already taken from the district, there are still many more millions left in the creek beds . A conservative estimate of the gold still remaining in one creek alone, Spruce creek, for a long time known as the 'prospector's meal ticket', would place the amount at anywhere from fifteen to twenty million .dollars, and there are a number of other creeks that have never been thoroughly worked, and some only partially prospected. That the true situation is beginning to be recognized by those who are on the lookout for a profitable field for investment, is born out by the fact that, within the last few years, New York capital directed by Mr. Charles V. Bob, who is also responsible for the opening up of the Engineer mine, has installed on Pine creek, where the first discovery of gold in the district was made, one of the largest hydraulic mining plants on the continent, utilizing six miles of the old hydraulic ditch of the Discovery Mining and Power Company, and over two miles of pipe line. On Boulder creek, where already two millions have been taken out, the Consolidated Mining and Smelting Company are on their third year of development work in opening up the unworked ground, while on Otter creek a newly organized French company have started a plan of development which will involve an expenditure in the neighbourhood of $200,000, and two or three years' work, before they can hope to find gold in paying quantities. It is probably safe to prophesy that placer gold will be produced in the Atlin district for the next fifty years

Jan 1, 1929

By W. D. Mulholland

"I ASSUME that any effort on my part to deal with the question of the importance of the mining industry is going to be largely an exercise in preaching to the converted, but there are one or two aspects that I'd like to particularly mention.The first is that, in terms of almost all factors, the mining industry is a very important industry in Canada. It is important in terms of employment in relation to the gross national product of Canada and it is particularly important in the international trade of Canada. So far from being insignificant domestically, it is also an extremely important factor in the international picture. That's an important point to bear in mind, because as we talk about all the other matters we never can lose sight of the fact that mining management always has to be conscious of its international competitive position. It is something that one forgets at one's peril, and to a somewhat greater extent than is true of many other industries, those managements have to compete in an international context for their markets, to some extent for their people for specialized skills and of course for finance. In the evolution of domestic policies it is a very, very perilous step to take to impair that competitive ability of the domestic mining industry."

Jan 1, 1972

By A. G. Storey, J. B. W. Bailey

"The Noranda Process at the Horne Division ofNoranda Mines Limited now smelts approximately 350,000 short dry tons of concentrate a year, which is 40% of the total smelter throughput. Campaigns are averaging 200 days and refractory consumption is much lower than in the conventional smelter.In this paper, details ofrecent operation are given, together with updated projections for operation with higher levels of oxygen enrichment.IntroductionThe Noranda continuous smelting process has been in operation at Noranda, Quebec, for six years and in that time it has smelted a million and a half tons of concentrate. It is currently smelting 1,200 to 1,250 tons per day of concentrate on an instantaneous basis"" and it is handling approximately 40% of the Horne smelter throughput.This paper will describe the current operation of the process and the improvements that have been made since 1976, when the process was described by L.A. Mills et al.lSince early in 1975, a high-grade matte averaging 73% copper has been produced, which is then sent to the converter aisle for final treatment. All the information in this paper refers to the operation of the process in the matte mode .Early in 1978, Kennecott Copper Corporation started up their new smelter near Salt Lake City, Utah , which has three Noranda Process reactors operating with high oxygen enrichment of the tuyere air (2). These furnace s incorporate some design improvements, which will be described briefly."

Jan 1, 1980

By G. Griffiths

"P. WitteWitteck DevelopmentThe implications of using a tower mill for fine grainding in the ore processing of tailings are significant. What can those of us who are in a research and development situation do when we recommend this equipment to a client? When this prototype is placed on stream next to a conventional grinding mill as you suggest how do we estimate the power requirements and the grind which will be achieved?ReplyLet me explain the Macassa circuit. The tower mill here was running in parallel with one of the ball mills. The feed entering the tertiary system is scalped in a primary cyclone. The finial cut is made in a secondary cyclone. The actual feed to the tower mill is the underflow from the two cyclones and was split to the ball mill and tower mill. During the testing we were unable to isolate the tower mill to determine its contribution to the overall system. We then started to look at the amount of material produced across the mill. We entered the mill at between 17% and 20% finished material and exiting at between 36% and 40% finished material. We were able to project, with a high efficiency classification system, and arrived at 6 Kwh/ton or better."

Jan 1, 1984

By H. Clare Horwood

"In the Red Lake area in northwestern Ontario the relationships between general structures and structures containing ore deposits are among the most unusual and most interesting of any in the Precambrian Shield. The more important orebodies, which are in the central-eastern part of the area, occur in a variety of rocks on the northeastern, eastern, or southeastern sides of a series of granite stocks. Other deposits in the western part of the camp also are structurally associated with granite masses .The relationships were determined in the course of general and detailed geological mapping by detailed analyses of the fracture patterns in the rocks adjacent to the orebodies. In every case it was found that the structures containing the ore were produced by compressive stresses from the direction of intrusion of the granite masses( 2).The Red Lake area lies in the Patricia part of the district of Kenora and is accessible by boat from Hudson or by airplane from Kenora, Sioux Lookout, or Winnipeg. A road from Vermilion lake, on highway No. 17, was opened in August, 1947.The first discoveries of mineralization in the area that proved to be of economic importance were made in 1925 by Lorne Howey and George McNeely for Haileybury interests and by Ray Howey and W. F. Morgan for Mcintyre-Porcupine Mines, Limited. Both prospecting ventures were organized because of information presented by Bruce(l) in his map and report for the Ontario Department of Mines. The discoveries, which were both along the same structure, a quartz porphyry dyke, later developed into the Howey and Hasaga gold mines. Other discoveries were made at intervals as a result of prospecting and development work on ground staked for its location."

Jan 1, 1954

By R. R. Stone

"This paper will examine the role of debt and equity in project financing and will illustrate the impact on the return to the project sponsor of each type. Conventional debt sources will be examined, as will product purchaser advances, foreign export-import bank loans and lease financing. The paper will review guarantees, charges against the project, dividend restrictions and other commitments. It will also discuss various features of sales contracts and the degree to which they can assist in securing financing. IntroductionThe cost of bringing new mining projects on stream is escalating significantly more rapidly than general rates of inflation. Reasons for this include the higher costs of safeguarding the environment and ensuring the health and safety of workers. The need to develop properties in more remote areas is also a significant factor. These higher costs have not been matched by increases in metal prices, making the task of financing these projects ever more difficult. At the same time, the imagination of borrowers and lenders seems boundless, and innovative schemes for financing projects are constantly being unveiled.It is probably safe to say that no two projects have ever been financed in precisely the same way and the number of financing options for any project is limited only by the imagination of the sponsors themselves. The objectives of the project sponsor represent the most important factor in determining the scope of possible financial arrangements. For example, the sponsor may wish to maximize over-all company leverage by isolating each of its projects in separate companies. In so doing, it hopes to facilitate more ventures than would otherwise be the case. These objectives point toward true project financing. Additional objectives may be to develop a number of its properties by joint venture and to reduce the amount of debt on the sponsor's balance sheet. Those sponsors whose objectives include minimizing over-all financing costs will wish to increase the number of financial options and, as a result, will not be so concerned with effecting true project financing. This approach may also provide ""greater certainty that tax benefits are utilized quickly."

Jan 1, 1980

By P. V. Avotins, I. Djurkovic, D. R. Nagaraj, M. Grunjic, A. Day

"As part of a major reconstruction and expansion of the Majdanpek Copper Mine, an investigation and optimization of the flotation collector regime was undertaken. The flotation response of the major minerals to various reagents and the effect of pulp chemistry was studied from both a fundamental and practical point of view. These studies led to plant trials and the eventual adoption of a modified collector suite which improved both copper and gold recoveries.INTRODUCTIONThe Majdanpek Copper Mine processes 40,000 tons per day of ore containing about 0.43% cu. In addition to copper, the ore also contains recoverable quantities of molybdenite and gold. The mine has been in operation since 1961 and is the largest in Yugoslavia. It is currently undergoing major reconstruction and expansion. The flowsheet of the Majdanpek concentrator is shown on Figure 1.The ore body is variable in composition and changes in mill feed require proper control of operating variables to achieve the optimum metallurgical results. A detailed study including grindability, flotation response, and solid-liquid separation was carried out on several samples of the ore. Flotation response and the choice of reagent chemistry were found to be very important in achieving the highest recoveries of metal values. An automatic reagent control scheme insured that optimum dosages were used in the plant.The flotation collectors used at the present time include sodium isopropyl xanthate (SIPX), AERO 3302 Promoter and AERO 5415 Promoter. The addition of AERO 5415 to the reagent suite is a recent development and was based on the favorable results obtained in the extensive laboratory testing program conducted to establish the optimum reagent combination and dosages. Subsequent plant tests confirmed that AERO 5415 provided significant improvements in copper and gold recoveries. A description of the mineralogy of the Majdanpek ore and details of laboratory and plant metallurgical data are given in this paper. The chemistry of AERO 5415 Promoter and its interaction with minerals relevant to Majdanpek ore are also discussed."

Jan 1, 1992