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By M. Gimpel, R. Galler, T. Antretter, H. Kargl, R. Tichy, W. Ecker, M. J. Mikl-Resch, G. Pittino

"A computational method based on a continuum-mechanical approach to simulate rock cutting is developed and evaluated. The aim is to obtain the local loading acting at the cutting pick during operation. The explicit FEM is chosen to model the pick-rock interaction. The presented method takes advantage of (i) an advanced material model (ii) a robust contact algorithm and (iii) fast calculations due to parallelization. A damage-plasticity law is chosen and modified with user-subroutines. A user integrated element deletion routine evades critical mesh distortions. Infinite elements at the model boundaries avoid unrealistic deformation wave reflection.INTRODUCTIONExcavation in mining and tunneling is a costly and complex process. Special equipment such as the roadheader (Figure 1) is employed to cut the rock in the excavation process but high material strengths limit their usability (Tockner 1999). Nowadays a challenge is to extend their field of application to harder and more abrasive rock materials. The forces on the pick (Figure 2) are of great importance and determine wear and especially the efficiency of the machine. Figure 2 shows the principle of cutting and the predominant forces. The variation of pick geometry, cutting depth or attack angle will result in an alteration of these forces and determine the efficiency of the process (Tockner 1999). The mechanisms of rock cutting follow the principle of indentation (Kou et al. 1999). Directly under the indenter a hydrostatic stress state evolves causing the material to fail only due to crushing and fragmentation mechanisms. In the close surroundings large strains emerge and tensile cracks are formed but in a further distance the material behaves elastically."

Jan 1, 2015

By M. Gimpel, R. Galler, T. Antretter, H. Kargl, M. Mikl-Resch, R. Tichy, W. Ecker, G. Pittino

"A computational method based on a continuum-mechanical approach to simulate rock cutting is developed and evaluated. The aim is to obtain the local loading acting at the cutting pick during operation. The explicit FEM is chosen to model the pick-rock interaction. The presented method takes advantage of (i) an advanced material model (ii) a robust contact algorithm and (iii) fast calculations due to parallelization. A damage-plasticity law is chosen and modified with user-subroutines. A user integrated element deletion routine evades critical mesh distortions. Infinite elements at the model boundaries avoid unrealistic deformation wave reflection.INTRODUCTIONExcavation in mining and tunneling is a costly and complex process. Special equipment such as the roadheader (fig. 1) is employed to cut the rock in the excavation process but high material strengths limit their usability (Tockner 1999). Nowadays a challenge is to extend their field of application to harder and more abrasive rock materials. The forces on the pick (fig. 2) are of great importance and determine wear and especially the efficiency of the machine. Figure 2 shows the principle of cutting and the predominant forces. The variation of pick geometry, cutting depth or attack angle will result in an alteration of these forces and determine the efficiency of the process (Tockner 1999). The mechanisms of rock cutting follow the principle of indentation (Kou et al. 1999). Directly under the indenter a hydrostatic stress state evolves causing the material to fail only due to crushing and fragmentation mechanisms. In the close surroundings large strains emerge and tensile cracks are formed but in a further distance the material behaves elastically."

Jan 1, 2015

By Unknown

We are indebted to the Consolidated Mining and Smelting Company of Canada Limited for the several pictures in this issue showing the progress made in new construction at Tadanac and at Bonnington Falls, B.C. Plate No. 1 shows the down-stream side of the No. 1 hydro-electric station of the West Kootenay Power and Light Co. Limited at Bonnington Falls, on the Kootenay river, at which 17,500 k.v.a. will be developed to meet the requirements of the enlarged zinc and lead refineries at Tadanac. The generators, exciters and switch apparatus were supplied by the Canadian General Electric Company and the step-up transformers by the Canadian Westinghouse Company Limited. The plant throughout was designed, manufactured and erected by Canadians. Plate No. 2 shows the casting room of the new lead-plant and plate No. 3 the new tank-room of the electrolytic lead refinery at Tadanac. These additions will increase the capacity of the lead refinery by some 150 tons daily. The extensions also include practically doubling the zinc plant, and the gold and silver refineries. With the exception of the new stack, all designing construction and installation of the various plants is being done by the Company's own employees at Tadanac. Plate No. 4 shows the progress made in the construction of the new reinforced concrete stack at Tadanac. This stack, of 21 feet inside diameter at the top, will be brick lined and when completed will rise 400 feet above its foundations: the tallest of its kind in the world. The construction is in charge of the Rust Engineering Company of Pittsburgh, Pa. Plate No. 5 is a panorama of the Tadanac smelters and refineries. The photograph was taken from the roof of the lead smelter and gives an excellent idea of the size of the plant and its surroundings. Tadanac produces electrolytic lead, zinc and copper and fine gold and silver. During 1924 the company treated 1,333,523 tons of ore and produced: 161,400,- 769 pounds of lead; 92,197,824 pounds of zinc; l,382,750pounds of copper; 4,074,044 ounces of silver, and 26,976 ounces of gold.

Jan 1, 1925

By D. Vanin

"Conventional single heading track drifting in the hard rock mining industry has not shown any significant improvements in advance rates, despite the advent of modern track jumbos and igh speed muck handling systems .This paper presents Kiena 's experience in using a 7 ft 2 in. diameter larva Mark 6 Tunnel-Boring Machine (TBM) for driving 6000ft of drift.IntroductionKiena Gold Mines is located about 5 miles west of the town of Val d'Or, Quebec, approximately 300 miles north of Montreal. The mine commenced production in October 1981 and has gone through various expansions of ore production with 287 916 metric tonnes in 1982 to reach 453 800 metric tonnes in 1986.Due to the majority of claims being covered by a lake, a grassroots exploration drive of remote areas of the property was required to allow diamond drilling on a yearly basis. High speed sequential excavation methods (SEM) of single heading drifting in the mining industry has not progressed much in the past 20 years despite the advent of electric-hydraulic jumbos, Haggloader and Hagglund type cars. Certain examples of record SEM drifting advances have been performed in the past but only under very specific ground and cost conditions."

Jan 1, 1987

By P. Nos, L. Kolbeinsen, M. W. Kennedy, A. Filzwieser, R. T. Jones, A. MacRae

Modern furnace designs often incorporate extensive use of cooled elements to achieve long campaign lives at high operating intensities. However, contact between water and high temperature fluids can result in powerful Boiling Liquid Expanding Vapour Explosions (BLEVEs). Therefore cooling such elements with water carries inherent risks when used under slag and particularly below molten metal or matte. Alternative cooling media exist that can reduce or eliminate the risk of BLEVEs. These media are analysed and discussed in the context of deeply cooled furnace elements. Important factors in selecting alternative coolants are explored including: critical heat flux, thermal limits, toxicity, flammability, unit cost, etc. Key cooling system design criteria are reviewed in the context of both traditional and alternative coolants. Results of Computational Fluid Dynamics are presented for an example tap-block cooler design using a number of selected coolants. Research needs to advance the safe use of alternative coolants are presented.

Jan 1, 2015

By Gordon Jackson

"There are two accomplishments of air and gas drilling: a new series of economic and mechanical challenges; and, acceptance as a standard drilling and completion tool.The new challenges are related to the concept of using a gaseous circulating medium in drilling for oil or gas. For purposes of discussion, a two part division has been made: the challenge of fluid invasion control and that of equipment and tools. Great strides have been made in the development of materials and techniques to combat formation fluid invasion. Chemicals and the ""mist drilling"" technique, now in use, have the versatility to cope with a wide range of downhole fluid entry conditions.Equipment and tools have been developed to meet the challenges of better, more economic drilling and completion possible with a gaseous circulating fluid. Economic and operational challenges remain.Acceptance of air and gas drilling as a normal operating tool was reached with difficulty. It is now established as a means of reducing costs in exploratory and develop-mental well drilling, exemplified in a recent study of 226 wells covering 419,407 feet of hole in the United States. Air reached the projected depth in 85 per cent of the operations, although formation water was encountered in 48.7 per cent of the holes. Slim hole bit performance and cost all compared for overall bit averages as part of analysis."

Jan 1, 1961

By C. O. Swanson

THE purpose of this paper is to discuss the use of the dip needle in the field of mining geology. The subject matter is new only to the extent that it reflects the writer' s added experience in recent years. The treatment is brief, and those interested in a more extended analysis are referred to the articles listed at the end of the paper. In the discovery and tracing of mineral deposits, the clip needle, like most other geophysical instruments, can be used in two ways. One method may be termed direct; the other, indirect. The direct method is that of finding or following certain ore-bodies by virtue of their magnetic properties. Explicitly, or by inference, it is the method which many mining men and practising geophysicists have in mind when they consider whether or not a certain property should be studied by geophysical means. In the ideal case, this method demands little or no knowledge of geological conditions. The indirect method uses the clip needle as an aid to purely geological studies in working out the structure of a mineralized area. Although not as simple as the direct method, it enjoys a much wider field of usefulness. The writer's experience in the past fifteen years, which is believed to be typical, is that the indirect method finds application four or five times as often as the direct method. The indirect method is of particular value because it furnishes information concerning the relationship between geological structure and ore occurrence. Most mining engineers will agree that structural control is an important factor in the localization of ore deposits, and therefore that the subject under consideration is of some interest in mining geology. Specifically, then, the present purpose is to outline the principles and practice of using the clip needle in working? out geological structure.

Jan 1, 1941

By Victor R. Eyzaguirre

Cerro Verde is one of several large porphyry-type copper deposits in Southern Peru. The copper occurs as primary sulphides, with a significant oxide capping. The exploitation of the deposit has been correspondingly divided into two stages, the first consisting of copper production from oxides, and the second from sulphides. Minero Peru successfully started the Stage I plant in June of 1977 with the first production of electrowon copper cathodes. This paper is essentially devoted to a description of the Stage I process, which can be summarized as follows: Ore is trucked to the primary crusher, where it is crushed to 225 mm and conveyed to a coarse ore stockpile. Ore withdrawn from the stockpile is secondary crushed to 65 mm, conveyed to a truck loadout bin, loaded into trucks and driven to the leaching pads. Ore is placed on the pads in lifts and sprayed with sulphuric acid solution to dissolve the copper. Copper-bearing solution forms a pond behind a dam at the lower end of each pad and is pumped from there to the solvent extraction plant. Copper is extracted from the leach solution into an organic phase and is then stripped from the organic phase to form a purified concentrated copper solution suitable for feed to electrowinning. In electrowinning, the copper is finally recovered as cathodes suitable for sale as refined copper.

Jan 1, 1978

By G. Wilson

"Satisfactory hydraulic performance of a centrifugal slurry pump is not the only design criterion. If abrasive wear exists the severity of any damage can be reduced and the life of the wearing parts prolonged by selecting the correct pump to suit the conditions of service. This paper is concerned with the design and construction of centrifugal pumps for handling abrasive solids. The wear phenomena due to the slurry being pumped and the materials used to combat abrasive, wear are outlined. The hydraulic design of the impeller and casing and their relationship to wear and the hydraulic radial and axial unbalance are discussed. The prediction of abrasive wear in pumps can not be precise, as many factors are involved - and this is the object of current research."

Jan 1, 1973

By V. A. Cooney

Introduction For the compliment paid me by the Institute's kind invitation to speak this afternoon, I am very grateful. For the astuteness of your officers in determining that encouragement should be given, through the medium of a paper, towards accident prevention in coal mines, the coal industry cannot but be grateful. Some day, and let us hope soon, a more developed paper may supersede this one. In the meantime, if some knowledge of what one coal field has been able to accomplish, even in the initial stages of its effort, will induce other fields and other sections of the mining industry to launch similar experiments, much good will result and a more developed dissertation on the subject will make its appearance.

Jan 1, 1946

By L. E. Fischer

The background for the 630-million-dollar-plus iron ore project at Kudremukh is outlined. The system and plants for mining, crushing, concentrating, transporting via a slurry pipeline, filtering and shiploading 7.5 million metric tons of iron ore per year are fully described. The mode of operation and the problems encountered in such a transfer of North American technology to developing countries are analyzed. Difficulties encountered during construction are discussed and the progress milestones made over a two-year period are enumerated.

Jan 1, 1979

By John C. Wilmot, Robert E. Brewer, Royce J. Smith

In March 2003, Phelps Dodge started up an innovative pressure leach facility for processing copper concentrates at the Bagdad mine in Arizona. This paper describes the development of the concentrate leaching plant at Bagdad and the operational results from start up to present. Optimization efforts and an approach to mineralogical modeling of the concentrate to calculate oxygen utilization are also presented.

Jan 1, 2004

By G. C. Mackenzie

At the last Annual Meeting of the Institute, Dr. C. V. Corless sketched the potential mineral wealth of Canada so clearly, graphically and with-all so entertainingly that one's imagination was fired with the promise held out to future generations for the tremendous expansion of the mining industry in the Dominion. Posterity will undoubtedly witness the fruit of much of the geographical search and survey that is now carried on by our government mining departments. Year after year the work advances, slowly but surely, new areas are . explored, older areas are surveyed in detail, the information being compiled in maps and reports of incalculable value to the prospector, the engineer and the general public. The immensity of the task of exploring, geologically, the outlying portions of the country, with the ultimate view of making valuable mineral discoveries, may be visualized from a study of Dr. Corless' paper and the subsequent discussion which took place and one becomes impressed with the fact that three-quarters or more of the problem can be included under the word "transportation". For instance Dr. Corless said, "The few geological explorers who have penetrated to these remoter regions . . . . . . have as a rule been compelled to stick closely to canoe routes,"; Dr. Goodwin remarked, "This barren Laurentian granite, which is put down on the maps as covering the greater part of this area, is the best guess the geologist could make from travelling along watercourses Within the next few years . . . . . . the Timiskaming and Northern Ontario railway will undoubtedly be extended to James Bay . . . . . . In order that we may be prepared for the probable influx of prospectors when transportation facilities to tidewater are provided, I think all available information on this district should be gathered together in handy form." All three-Corless, Goodwin and Cole-emphasize the well-known fact that explorers, geologists and prospectors working in new country must stick to the watercourses and that transportation by rail, road or water has always been the all-important deciding factor in facilitating the exploration and development of remote districts. Dr. Corless did, however, suggest other means of transportation in stating, "The aeroplane will be of assistance in future study of some parts of these remote areas."

Jan 1, 1924

By S. Kariyawasam, R. McNealy

Pipelines are subject to multiple threats often requiring quantification of pipeline risk and engineering evaluation of in-line inspection and other data to effect discovery of conditions defined by the regulation. Public concern and pressure from regulatory bodies are accelerating the need for pipeline operators to formalize and intensify their approach to integrity management. Most operators need a phased approach to progressively adopt the most relevant and needed assessments. The organized and relevant assessment steps need to be introduced according to data available and maturity of the integrity management program. Each refinement to the quantification offers distinct advantages to the user. In this paper, the progressive integrity assessment solutions using quantitative methods are presented. Methodologies for engineering evaluation of integrity in-line inspection data for immediate and future integrity are summarized. Corrosion is used as an example, but the approach is applicable to any time-dependent defect based hazard. Strategies for pipeline integrity management are discussed.

Jan 1, 2005

By G. M. Carrie

Introduction The subject of basic refractories is daily becoming of increased importance in metallurgical processes, and there is a constantly growing necessity for the development of better materials. This fact, together with the realization that Canada possesses one of the best sources of such refractories in the British Empire, if not in the world, made it appear? advisable that the subject be presented to the Empire Mining and Metallurgical Congress at the 1927 meeting. Having been in close touch with developments in the Canadian product during the past five years, G. M. Carrie was requested to prepare such a paper. The Canadian producers of magnesia refractories have succeeded in developing the product to a place where it has almost entirely displaced imported materials from the Canadian market. These developments were made possible by a close study of the methods of preparation of the material, and by an exceedingly careful control of the manufacturing process so as to obtain a thorough blending of the different constituents with the resultant uniformity of composition. This point is very important to the metallurgist, as un-uniform materials are a potent cause of difficulties in most manufacturing processes and the constant trend is towards their elimination. The temperature at which the Canadian material is burned ensures high specific gravity and thorough shrinkage. The grain size of the product is so controlled that the voids are only just sufficient to allow of proper bonding, thus making possible a dense, hard bottom affording high resistance to erosion and shock. Careful proportioning of the constituent elements absolutely prevents disintegration.

Jan 1, 1927

By F. S. Thurner

"This paper describes the engineering and construction activities of the ""design-build"" project awarded to the joint venture of Foundation-Comstock-Janin for the construction of the plant and wharf facilities, camp site, power plant and all supporting services. As a member of the Foundation Group of companies at that time, Fenco actecl as consulting and design engineers for the project. Particular emphasis is given to the problems which adversely affected design and construction activities due to prevailing arctic conditions and the remote location of the project. The paper also describes the approach taken in the investigation of the site and soil conditions as well as the selection of the special structures for the 225,000-toncapacity fibre storage building, the wharf structure for 50,000-dwt vessels, and the 1,000-tph-capacity reclaiming and ship-loading facilities . It further covers the logistics problems and the scheduling activities related to the short duration of the shipping season, and the transportation of equipment and mate1•ials by sea as well as by air."

Jan 1, 1976

By P. J. Bourassa

Incorporated in 1957 under the laws of the Province of Quebec, Quebec Cartier Mining Co. undertook the development of its low-grade iron ore reserves located at Lac Jeannine in the southwest extremity of the Quebec-Labrador trough. This challenge comprised the construction of a 200-mile access road, two towns, a 191-mile-long railroad from Port Cartier to Lac Jeannine, a hydro-electric generating plant on the Hart Jaune River, and mining, crushing, concentrating and ancillary facilities to support a yearly production of 8.0 million tons of iron ore concentrates at 66% Fe. In order to meet increasing market demands for iron ore concentrates concurrently with the depletion of its Lac Jeannine reserves , Quebec Cartier announced, late in 1969, the first step toward bringing into production a new iron ore deposit, known as Mount Wright, located 70 air miles northeast of Lac Jeannine and 25 miles southwest of Labrador City, Newfoundland. In September 1970, the company announced its decision to develop and bring into production its Mount Wright reserves at an annual rate of 1 8.4 million dry long tons. The scope of this project included the construction of an access road linking the mine, the new town and Labrador City, Newfoundland, the extension of the railroad by some 86 miles, the construction of an ore concentrating plant with all the ancillary facilities, the development: of the mine, the construction of a pourer transmission line and a new town adjacent to Lake Daviault. The Mount Wright story is divided into five individual papers covering: (a) the history and development of the project; (b) the mine; (c) plant control by a process computer; (d) crushing, grinding and concentrating; and (e) the townsite of Fermont.

Jan 1, 1977

By A. Mitura

The paper presents the initial investigation of possible energetic applications of chosen wastes from groups: 06, 03, 05 and 01, including coal slimes being secondary product of hard coal processing. These categories of wastes are catalogued according to the polish law, where 06 ? wastes from production, preparation, purchasing and application of products of non-organic chemistry; 03 ? wastes from wood processing and from plates and furniture, celluloid mass, paper and card board production; 13 ? oil wastes and wastes from liquid fuels; 01 ? wastes produced by searching, extracting, physical and chemical processing of ores and other mineral raw materials. The change of combustion heat value was evaluated in produced energetic mixtures containing these types of wastes together with the change of their individual components. All combinations of ingredients were taken into consideration giving 256 various mixtures, from which 36 were selected to investigation. This allowed the performance of statistical factor analysis. For such prepared materials the application of regressive method was proposed in purpose of calculating combustion heat value and then the comparison of empirically determined and theoretically calculated heat values was performed. The change of regressive coefficients can be determined by the nature of Hess law (eq. 1) what was investigated and the attempt of its explication and validation was done.

Aug 1, 2013

By D. C. Sharpstone

THE Polaris-Taku mine is a new gold property, situated in the far north-west corner of British Columbia. Production was started in November, 1937, at the rate of 150 tons a day, and recently has been increased to 200 tons. The property, which promises to become one of British Columbia's important gold mines, was developed and brought into production in twenty-nine months after work was started on it as a virtual prospect in June, 1935, by Edward C. Congdon and associates. Inaccessibility, extraordinarily complicated geological problems, and difficult metallurgy retarded development of the property before acquisition by the present interests, an::l, in fact, discouraged two companies that had spent substantial sums upon it from continuing development. This paper is concerned with reviewing the development of the property and describing the principal features of the geology, the mining and metallurgical practices, and the equipment employed. Acknowledgments The writer is indebted to Mr. Edward C. Congdon, President of the Polaris-Taku Mining Company, and to various members of the mine staff for their assistance in assembling the data for this paper. Special thanks are due to Mr. George G. Griswold, Jr., of Butte, Montana, who generously and painstakingly prepared the section dealing with milling and power. Microscopic studies of ores were made by Professors Frank Grout an::l G. M. Schwartz, of the University of Minnesota, and by Mr. Griswold.

Jan 1, 1938

By Mike Rylatt

"The BHP Diamonds Inc. and Blackwater Group (Dia Met Minerals Ltd., Charles Fipke and Stewart Blusson) joint venture began production at Canada=s first diamond mine during the last quarter of 1998.Construction of the processing plant began in mid 1997. During the 1998 winter season, the heavy process plant equipment was delivered to the Ekati site, 300 km NE of Yellowknife, by the ice road. Towards mid 1998 the construction activities were complete and commissioning began. The mine officially opened in October 1998.Initial production of 9000 tpd kimberlite will be from the Panda pipe grading 1.09 ct/t at an average value of US$13O/ct.Processing starts with a gyratory crusher reducing the ROM kimberlite to 90% passing 15Omm before further reduction to minus 75mm in a WaterFlush crusher. The crusher product discharges into a 4m diameter x 7m long primary scrubber. After screening, the minus 75 +1 mm kimberlite is conveyed to a 250 ft feed bin ahead of the 1.7 m diameter x 1.1 m wide high pressure grinding roll. The HPGR produces 50% minus lmm in a single pass, the compacted flake product is dis-agglomerated in a secondary scrubber. The scrubber product is screened into a minus 25 +lmm heavy medium separation plant feed and conveyed to a 375t HMS feed bin ahead of two 150 HMS modules. Milled 270D ferrosilicon at a slurry density of 2.6 g/cc and HMS feed are pumped to three 420mm diameter cyclones. Heavy mineral concentrates, approximately 1 % of the plant headfeed, are pneumatically transported to the Recovery plant for final diamond recovery using wet high intensity magnetic separators and high intensity (attrition) milling prior to three stages of x-ray recovery. At full production, Ekati will produce approximately 2 kg/day of diamonds.This paper details the later commissioning phase and the first three months Oof operational activities during the build up to full production at the Ekati processing plant."

Jan 1, 1999