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By M. C. Villeneuve, P. A. Siratovich

We present an integrated analysis of laboratory-based thermally induced fracturing and results of numerical models to give insight to the role of thermal shock fracture on geothermal reservoir rocks. Thermal stimulation is a reservoir permeability enhancement technique applied to commercial geothermal reservoir rocks to enhance fluid injection capabilities for spent power plant working fluids. The process is well known to enhance permeability but the thermodynamic and physical constraints of the process are less certain. In an attempt to constrain the interaction and the ideal conditions that lead to permeability enhancement, experimental procedures were carried out to mimic the conditions that a reservoir rock would experience during a thermal stimulation using temperature differentials ranging from 50-300°C. Samples underwent such thermal gradients under controlled laboratory conditions and were characterized for the changes to permeability, porosity, ultrasonic velocities, dynamic elastic moduli and petrological changes. The thermal stimulation was simulated in a FLAC2D thermal numerical model to investigate the nature of the thermally induced changes in the sample. The development of this model also allows us to investigate the relationship between geological characteristics and the ability to thermally stimulate any type of rock. The results indicate that numerical thermal shocking experiments are corroborated by laboratory-based results. The implication of this study is that the refined numerical models present an insight to the conditions and constraints under which thermal stimulation can prove to enhance permeability that could not be gained through purely laboratory-based studies.

Jan 1, 2015

By L. Voisin, G. Damm

"In order to develop a new pyrometallurgical process for eliminating detrimental arsenic and antimony from the impurity-rich matte produced from copper concentrate, and for treating the occasionally generated speiss in nonferrous smelting processes, the phase relations in the Fe-Cu-S-As-Sb system saturated with carbon at 1473 K were investigated. The distribution of elements between the condensed phases at the miscibility gap, where three equilibrated phases of iron-rich alloy, copper-rich alloy, and matte coexist, were also studied. The investigation was carried out by performing a series of laboratory scale experiments in an electrical furnace at 1473 K, followed by a quenching method on the final stage. The samples obtained from the experiments were analyzed by using Inductively Couple Plasma (ICP), Atomic Absorption Spectroscopy (AAS) and Carbon Infrared Spectrometry (CIS) techniques.The results were compared with previous investigations for the Fe-Cu-S-As-C and Fe-Cu-S-Sb-C systems and discussed on the basis of the molar fraction distribution for both arsenic and antimony in the matte phase at five different matte grades. It is expected that by using this phase separation technique it might be feasible both, the cleaning of a complex copper matte and the elimination of arsenic and iron together with an acceptable amount of antimony into the iron-rich alloy phase, which can be discarded as a harmless and smaller deposit."

Jan 1, 2014

By J. W. Smith, J. G. Eacott, D. H. Napier

"Three hydrometallurgicat processes (Noranda chloride leach, B. C. Research biological leach and Sherritt-Cominco activated oxygen leach) and the Noranda pyrometallurgical process have served as the basis for design projects in the final year of the chemical engineering program at the University of Toronto. Each member of a team of five or six students devotes about 200 hours to the project and the final report is expected to include an economic analysis.None of the processes has been developed to full- scale plant, nor, in the case of the B.C. Research and Noranda processes, were pilot plant data available. Nevertheless, the designs developed provide a useful basis for a preliminary estimate of capital and operating costs and for a preliminary assessment of project feasibility.This paper discusses the approach used in the design projects with respect to engineering and economic aspects, and outlines the educational features and benefits of such a program as well as some of the problem areas that arise.IntroductionAs part of the undergraduate degree course in chemical engineering at the University of Toronto, students devote some 200 hours to a design project in their final year. Hydrometallurgical processes, not yet proven at the commercial scale, have been selected for study. The students are required to develop laboratory and / or pilot scale results into a conceptual plant design, using sound engineering principles. Capital and operating costs are then determined and a preliminary feasibility study and economic analysis are carried out."

Jan 1, 1986

By M. Scobie, G. R. Baiden

"This paper describes recent developments at Inco Limited, Ontario Division, in the field of information systems for automated mining. A CA TV cable network has been combined with a broad spectrum radio antenna system to allow the supply of voice, data and video services to underground mining. The system formed the basis of a field experiment at the Copper Cliff North Mine of the Ontario Division in 1990.The experimental information system was developed to supply underground mining with voice, data and video services to mobile and stationary locations. In order to test the communication system, telephones and radios were linked together with the outside phone lines for voice communication. Stationary data was implemented on a SCADA (Supervisory Control and Data Acquisition) system for mine monitoring and control using PLCs (Programmable Logic Controllers), while using personal workstations for the mine planning and engineering functions. Stationary video was installed in the experiment to observe crushing, conveyor transfer points and skip dumping areas. Mobile data and video were tested by the teleoperation of an LHD. The functions supplied to the vehicle were monitored through a computer, with control being maintained through a standard radio interface and real time video pictures for the operation of the machine.This paper discusses the field testing of the information system and results achieved to date. It concludes by discussing the options considered to be open to provide information systems for future automated mining."

Jan 1, 1992

By Stuart McTavish

"The Brunswick Mining concentrator processes 10,000 D.S. T. per day of a complex sulphide ore. Four separate concentrates- zinc, lead, copper and bulk-are produced by selective flotation. Several major changes have been made to the Brunswick flotation circuit to improve the process and control. This paper will describe the present flotation practices at the Brunswick Concentrator. Special emphasis is given to the conversion of two of the primary circuits to an SO2-aeration flowsheet, and to the addition of a new secondary zinc flotation circuit that produces a zinc concentrate from the plant tailings. IntroductionBrunswick Mining and Smelting Corporation operates a zinclead- copper and silver mine and concentrator near Bathurst, New Brunswick. Since the start-up of operations in 1964, the flotation flowsheet has undergone major modifications to process the increased tonnages and to produce a greater number of concentrates. The flowsheet for the concentrator as it was in 1971 has been described by Neumann and Schnarru) and by Ersklneco. Since then, in 1971, the No.6 concentrator was converted from bulk flotation to selective flotation to produce a copper, lead and zinc concentrate. A separate zinc upgrading circuit was installed in 1972 and a bulk flotation or dezincing circuit, which reduced the zinc in the lead concentrate, was started in 1973. In 1976, the secondary zinc circuit was initiated.In addition to these new circuits, changes have been made to the existing circuits to simplify their operation."

Jan 1, 1980

By Paul Semple

"In 2007, Noront Resources Inc. discovered the high grade nickel copper PGE deposit in northwestern Ontario in a region now known as the Ring of Fire. Since the initial discovery, Noront has advanced the Eagle¹s Nest Project and in September 2012 released a feasibility study for the development of the Eagle¹s Nest Project. This paper summarizes the results of this recent study and outlines additional work planned in the next stages of project development. INTRODUCTIONThe following paper summarizes the findings of the recently completed feasibility study on Noront Resources Ltd.’s Eagle’s Nest Project. The feasibility study was compiled into a NI 43-101 report by Micon International. This paper is intended to summarize the major technical findings and for complete information, interested parties can find the entire NI 43-101 report at www.norontresources.com or on SEDAR.LOCATIONThe McFaulds Lake project area, which includes the Eagle’s Nest deposit, is located at approximately UTM 5844000 N and 547000 E, and between approximately 52º42’ and 52º50’ N latitude and 86º06’ and 86º24’ W longitude, approximately 250 km west of the community of Attawapiskat on James Bay and 575 km northwest of Timmins. The closest all-season accessible community to the McFaulds Lake project area is Nakina, 300 km to the south, where there is a paved airstrip, in addition to all weather road and railroad access (see Figure 1).The First Nations communities of Webequie and Ogoki/Marten Falls are located 90 km west and 120 km south southeast of McFaulds Lake, respectively. Both communities are served by regularly scheduled air service, primarily from Thunder Bay; both Thunder Bay and Timmins serve as support centres for the James Bay communities and the exploration projects in the area."

Jan 1, 2013

By J. I. Mathis

"The failure that was utilized for developing this model was a double bench-scale failure, approximately 20 m in height, in the Misery pit at BHP Billiton’s EKATI mine site. The bench that failed was excavated in biotite schist. Due to previous problems with bench-scale toppling failures, this bench was excavated with a 70° inclined, 30 m deep preshear. Upon exposure, the wall was very clean with half-barrels commonly observed from the pre-shear operation.In August 2003, a bench failure of about 1000 t occurred in this pre-sheared biotite schist (Fig. 1). Upon examination it was noted that the foliation that paralleled and dipped at 70° into the face when excavated was approximately horizontal at the top of the failure (Fig. 2). While the failure mode itself appears complex, the failure was apparently driven by three factors:• a low-angle, low-frictional strength fault or discontinuity at the base of the failure area;• water either contributed meteorically from precipitation and/or from permafrost melt; and• foliation planes providing a viable toppling geometry once toe block motion began to occur.The above details are illustrated in Figure 3.After considerable thought and analysis, a model was postulated for the failure.It is thought that the entire failure had been triggered by displacement of a toe block (Fig. 4). This toe block is bounded on the back by foliation, the bottom by a low-angle, lowstrength fault, and the front by the bench face. Water pressures behind the bench face developed forces on the block as can be seen in Figure 5. These forces were sufficient to induce block motion. As can be seen in the relative shear strength diagram in Figure 6, only a small amount of water is necessary in the face to initiate block displacement. Note that in this figure, a simplistic piezometric pressure distribution was assumed."

Jan 1, 2004

By Harry F. Weaver

WHEN 1 was assigned by the Director of the United States Bureau of Mines to present a paper at this annual meeting of the Mining Society of Nova Scotia, 1 was grateful, honoured, and elated to realize finally a life-long desire to see your beautiful land and visit with you who have the good fortune to live and work here. Naturally, in preparing for this important event, 1 wanted to give you something of special interest within the limits of the subject so I chose an area dose to my heart -the operation of our Federal coal mine inspection service, which has, as its fundamental purpose, the prevention of accidents in and around ?Coal mines. In 1957 the United States had 10,879 active coal mines scattered throughout 28 States and the Territory of Alaska. The production of coal for the year was about 515,472,000 tons, including 2.5,472,000 tons of anthracite and 490,000,000 tons of bituminous coal and Hgnite. Anthracite is mined principally in a comparatively small area of one State. AU the 28 States and the Territory produce bituminons coal and/or lignite. The beds mined range from 18 inches to more than 100 feet in thickness and from the horizontal to the perpendicular.

Jan 1, 1958

By F. T. Rabbitts

Introduction When the investigation of radioactive ores began at the Mines Branch about five years ago it was at once evident that improved chemical methods for the determination of uranium were essential. The published methods available were time-consuming and insensitive and were lacking in accuracy and precision. It was desirable to obtain methods which would be rapid, sensitive, and accurate. They should also allow for the possible presence of any interfering elements and should be adaptable to routine analysis by technicians. Chemical methods are necessary to provide standard analysed samples for counting and to check analyses by counter methods. Moreover, counter methods cannot be used, and only chemical methods are suitable, when the sample is not in equilibrium, as with weathered minerals and leach residues. As leaching processes are improved, more sensitive chemical methods are required for the increasingly lower content of uranium in the leached residues. When the leaching process reaches the plant stage, speed of analysis becomes more important, without sacrificing accuracy. The purpose of this paper is to describe briefly .the methods used at the Mines Branch for the chemical analysis of uranium in ores. These methods represent the results of investigations by a number of groups in the United Kingdom, the United States, and Canada.

Jan 1, 1952

By W. Noel O?Brien

Introduction Since 1930 numerous improvements have been made in equipment designed for the mechanical removal of broken ore in underground mining operations. New applications of mechanical equipment, as? well as improvements and adaptations of well established systems, are being made continually. It is the purpose of this paper to discuss present-day equipment for the removal or transfer of broken ore by means of a powered hoist and scraper arrangement. The terms used throughout the paper are those commonly employed in the trade literature and by mining men. The terms slusher hoist, hoist, and scraper hoist are used inter-changeably to mean a machine, powered by compressed air or electricity, with drums for the winding of wire rope. The tail rope, also known as the pull-back rope or return rope, drags the empty scraper toward the tail-sheave, that is, back to the loading point. No attempt is made to cover the entire field of application of scraping methods. Rather it is the? writer's desire to emphasize the fundamental principles of scraping practice and design and to relate them to some modern applications. The available literature on scraping practice has been freely used. together with personal observation and information and advice of practising engineers and representatives of companies manufacturing slushing equipment.

Jan 1, 1951

By C. H. Attwood

Introduction In presenting this paper on the water-power resources of the Province of Manitoba, it was considered that a brief resume of the power resources of Canada, of the power already developed, and its utilization in the industries 9f the country, would be of particular interest in showing the rapid progress that has already been made. Amongst Canada's national assets, water power occupies a foremost place because of the facilities it provides for the development of her other great natural resources. The rapid development of the mining, pulp and paper, and general manufacturing industries, and the concomitant growth in urbanization, with its numerous demands for domestic, commercial, and municipal service power, have combined to stimulate hydraulic development to a point surpassing even the most sanguine predictions of a few years ago. With the bringing into operation during 1928 of hydraulic turbines aggregating over 550,300 h.p., and of a further 378,400 h.p. in 1929, Canada's total hydraulic development at the end of 1929 amounted to over 5,700,000 h.p., and in this year, 1930, the active construction in hydro-electric plants throughout the country totals in excess of 1,600,000 h .p.

Jan 1, 1930

By D Martín, G. Díaz, F. Cubeddu, A. B. Mejias

The Modified ZINCEXTM Process (MZP), developed by Técnicas Reunidas, is an industrially proven flexible process. It can handle a wide range of primary and secondary raw materials, producing SHG zinc. The core of the Modified ZINCEXTM Process is the zinc solvent extraction unit. This unit is an effective barrier for any leachable impurities present in the raw material. As a result of this an ultra-pure zinc solution is always obtained. The high versatility of the process makes the application of the technology in different scenarios possible. MZP can be effectively applied when developing a whole new plant (Skorpion) or adapting its scheme to an existing refinery (Akita), in both cases giving the same results. Flexibility in terms of capacity of the plant is a great advantage of the MZP, there is the possibility to adapt the global process to a wide range of production capacities. Zinc production capacities of over 150 000 t/a may be achieved with a single solvent extraction plant train. The robustness of the Modified ZINCEXTM Process has been recently proven on two new plants currently in operation: Portovesme (Italy) and Horsehead (USA) after start up during 2013. The status of both plants is described in this paper.

Jan 1, 2014

By D. S. Speakman

The copper-zinc orebody at Sherritt Gordon's Ruttan Mine occurs in a structurally complex area of the Rusty Lake greenstone belt in northern Manitoba. Problems in interpreting drill results indicated a large deviation, and the structural complexity an erratic deviation, of drill holes. This was confirmed when a surface hole was intersected 420 feet to the left of line on the 800 level. This problem acted as a catalyst in promoting a search for a suitable down-hole survey method. The instruments investigated included magnetic multishot and gyroscopic units as well as the ABEM Reflex-Fotobor. Only the Fotobor came close to meeting the company's needs of simplicity, reliability, accuracy and ownership. In this paper, the methods of operating this instrument, as well as the data extraction and reduction techniques, are described. Data on the accuracy and repeatability of the instrument are presented, and a tabular presentation of the results of surveying on 86 holes totalling 64,000 feet of drilling is made. Preliminary statements of the results of ongoing research on causes of hole deviation are presented and recommendations for minimizing deviation are given. The use of the survey device is recommended in areas of structural complexity, for very steep or backsight holes and where expected ore intersections are missing.

Jan 1, 1978

By J. Scrimgeour

"The word ""instrumentation"" has expanded from its original meaning, which in engineering perhaps referred to measuring apparatus alone. In its broadest form, it now includes sensors, display instrumentation, standard pack-aged controllers and, most recently, the use of stored program computers for on-line process control. The paper traces the evolution, in tutorial form, of the successive application of mechanization, measurement instrumentation, automatic control, central operating systems, programmed control, process computer control, direct digital control and, finally, hierarchies of computers used for process control and corporate management as a fully integrated business system. In the field of industrial minerals, the cement industry has seen the most widespread acceptance of these techniques. Computer control has been accepted as the way of life for the blending of chemical materials and for on-line control of the cement kiln. Accordingly, the cement application is selected for further presentation in the paper. This illustrates the trend progressing from control of single loops on process variables toward the objective of total control of the product quality. The economic justification for instrumentation, centralized control, automatic control and computer control is .discussed with reference to savings in fuel, maintenance, operating labour, depreciation, power and product quality improvements."

Jan 1, 1967

By Kazuhide Nakaniwa

In this research, we devised a measurement method using total stations (TSs) which have ?the Baum? which is a concentric circle reticle, as substitute for crosshairs. The Baum owes its name to the similarity between the concentric circles and trees (Baum in German). By setting one circle on both of edges of cylinders, operators can set their sights on points on the center line of the cylinders, and also can measure positional coordinates of the points. Also, by measuring two different points on the center line, operators can measure the position and tilt of the axes of the cylinders. Furthermore, we developed a pile driving navigation system. Foundation piles are used for various structures, and their forms are generally cylindrical. Especially, although it is difficult to drive tilted pile foundations, their usage are expected to expand due to their high earthquake resistance. Yet, a method to accurately measure the tilts of piles has not been established. However, we proved that operators can obtain adequate accuracy to control foundation piles through the measurement experiment using this system. Using this system, the information of the pile is measured using a TS, transferred to a PDA, and displayed from the operator?s view of the piling machine.

Aug 1, 2013

By I. C. Christopher

Introduction The geology of the Cochen-our Willans gold mine has been described in reports by the late Dr. H. C. Horwood (1) in 1940 and by Dr. J. P. Nowlan (2) in 1947. Information from these and other (unpublished) reports has been incorporated in the present paper, together with some recent ideas regarding structural features which are at present being used to locate ore shoots. Location and History The mining claims of Cochenour Willans Gold Mines, Limited, occupy 705 acres in Dome township, on the east shore of Red lake opposite McKenzie island. Adjoining properties are those of McKenzie Red Lake Gold Mines on the west, Boymar Gold Mines on the north, Marcus Gold Mines on the east, and Martin-McNeely Gold Mines on the south. The claims of the original group were staked by W. M. Cochenour, Dan Willans, and H. G. Young, and the Cochenour Willans Syndicate was formed in 1928. Work was carried out by the Syndicate and several other companies during the next eight years with inconclusive results, due to the irregular occurrence of the ore. In 1936, Cochenour Willans Gold Mines, Limited, was incorporated and production was finally started late in 1939.

Jan 1, 1951

By H. A. Hamza, J. Visman

"This is a report on the combined application of ""long-chain"" flocculants and classifier cyclones in the field of slimes treatment, with emphasis on the simultaneous thickening and clarifying of industrial effluents, at low cost. The principle of the process described below involves: (1) the formation of small floes of relatively great strength, by sequential dispersion and conditioning, with average floe size of about 1501 microns; (2) the floes being of sufficient strength to withstand the shearing forces operating within a cyclone and consequently behaving as solid particles with an equivalent diameter (Stokes) that exceeds the size cutpoint of the classifier cyclone; (3) the removal of flocculated solids by means of a classifier cyclone the size cutpoint of which permits effective separation of these solids from the water. Results of test work to date indicate that a broader use of cyclones in industry is possible with the above types of flocculants because the submicron particles and colloidal material are readily collected and clear water is produced, with the attendant advantages of compact construction and low cost that are characteristic of centrifugal separation. The process generally permits classifier cyclones of medium throughput capacity (e.g. 12-in. diam.) to be used for clarifying effluents that contain minus 10-micron particles."

Jan 1, 1973

By N. A. Jabit

The dissolution behaviour of ilmenite in acid solutions has been studied by many researchers to improve the leaching efficiency. Most studies which utilized natural ilmenite from different origins resulted in different reactivity due to the alteration caused by the weathering process. Previous researchers have suggested that the greater reactivity shown by some ilmenite samples towards sulphuric acid may be a result of the mineral being relatively unaltered. In the present study a rotating synthetic ilmenite disc of 2.2 cm diameter was subjected to leaching studies in hydrochloric acid. The dissolution rates of iron and titanium from synthetic ilmenite were determined in hydrochloric acid solutions (4 M to 9 M) over a temperature range of 50 to 80°C. Results show that the rate of dissolution of both iron and titanium increased with the increase in acid concentration. However, the rates decreased with time and obeyed a parabolic rate law indicating the blockage of the surface by an insoluble product. The rates of dissolution of both iron and titanium were higher in the presence of SnCl2 and remained unaffected with time indicating the reductive role of SnCl2 which inhibits the formation of surface blocking solids. Application to natural ilmenite is also discussed.

Jan 1, 2014

By S. W. Marcuson, P. J. Mackey

The 1973 Oil Embargo and succeeding disruptions in supply had a profound effect on energy costs and consumption patterns in the developed world. This was especially true in the USA where post World War II growth, fueled by low-cost imported oil, left the country dependent on uninterrupted oil shipments from the volatile Middle East. In this atmosphere, Professor H.H. Kellogg of Columbia University, convinced of the necessity of good environmental stewardship by the writings of the era’s leading environmentalists, developed a methodology for evaluating energy and process efficiency of metallurgical processes and wrote a series of papers describing and applying the techniques. One of these, "Energy Use in Sulfide Smelting of Copper" is recognized as a seminal work which both described the state of energy usage in copper smelting in the mid-1970’s and portended future developments. The background to these papers is examined and the current and past Cu-Ni matte smelting practices in Canada are examined in the context of the results. Data from early 20th century publications describing reverberatory and blast furnace operation is employed to show that energy consumption for much of the century was several multiples higher than that calculated for best reverberatory operation in the 1970’s.

Jan 1, 2015

By W. Basuki, B. Setyotomo, L. Hakim, R. Hendrajaya

Due to high crack sensitivity of slab product of gas and oil line pipe application, its steel making process and alloy composition were evaluated and then improved to overcome its critical solidification process and reduced surface defects. The study was conducted at Slab Steel Plant Krakatau Steel. The purpose was to improve slab surface quality by reducing surface defects so that the slab surface doesn't need to be totally repaired. The method applied was by performing plant trial process, which the secondary process parameters such as alloying method and the casting parameters such as casting powder selection, metallurgical cooling, mould level control, and superheat were continuously monitored and then adjusted to the surface quality of the product. Based on the calculation of Ferrite potential of the steel, the chemical composition was designed to achieve optimum casting parameters in order to avoid high shrinkage during solidification. The results of the study are decreased surface defect quantity, and smooth casting process. The quantity of crack decreased by almost 90%. The slab surface repairing was significantly reduced from 85. % to less than 10%. These new casting parameters and developed alloy composition are then used and standardized for the mass production of the steel.

Jan 1, 2005