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By Thiann R. Yu, William J. Quesnel

At Kidd Creek, the annual production of 4.5 million tonnes of ore has been achieved primarily with sublevel blasthole stoping. This mining method has allowed underground operations to meet the designed production capacity while maintaining an outstanding safety record. To achieve this goal, rock mechanics principles have been integrated into each facet of mining in the planning stage, in the production stage, and in various stages of ground support. This paper evaluates the two adopted mining sequences based on ground stress patterns, blasting control, ground reinforcement, backfill support, and numerical modelling for stope stability at the mines.

Jan 1, 1984

By F. C. Schora, H. P. Meissner

Both a graphical and an analytical technique are presented for calculating stream compositions and temperatures in adiabatic staged systems in which solids travel countercurrently to a gas stream. Such a system might be a tower containing several plates, on each of which the descending solid is fluidized by the rising gas stream. Examples are presented in which chemical reactions occur, including the oxidation of SO, by a solid catalyst and the gaseous reduction of iron oxides. COUNTERCURRENT staged processes involving reactions between solid and gas streams are becoming more common. These operations are generally carried out in a series of beds of fluidized solids, with each bed or "plate" acting as a stage. Fig. 1 is a schematic diagram of such a series of stages located in a column, down through which a solids stream moves from stage to stage counter to a rising gas stream. Typical reactions carried out in such systems are the dehydration of aluminum trihydrate, the calcining of limestone, and the gaseous reduction of iron oxides. Calculation of the performance of these counter-current systems rapidly becomes more complex with increases in the number of stages and in the number of chemical reactions occurring. Calcula-tional procedures for isothermal operations of such systems have been described.4 Actual tower operations, however, are generally adiabatic, and in consequence far from isothermal. The object here is to present both graphical and analytical techniques applicable to such adiabatic towers operating continuously and in steady state. In this introductory discussion, the graphical techniques presented are of the McCabe-Thiele type, rather than of the Pon-chon type. In all the examples presented, it will be assumed that both thermal and chemical equilibrium are attained in each bed. The assumption that the gas and solid streams leaving each bed are at the same temperature as the bed is in accordance with the familiar behavior of actual fluidized solid systems. Chemical equilibrium, on the other hand, is not necessarily attained in any given stage between these two streams, even with deep beds, since reaction rates may be slow. In the last section of this paper, discussion is presented of methods suitable for use when chemical equilibrium is not attained. The adiabatic tower in Fig. 1 has "n" stages numbered from 1 to n, starting with the bottom stage as number 1. In analyzing this tower's performance, it is important to express gas flow rates in terms of a key component or element which remains completely within the gas stream throughout the tower. Similarly, solid flow is best expressed in terms of a key compound or element which remains within the solid phase throughout the tower. Thus, in burning limestone with a hot flue gas, the gas flow might be expressed as G, the pound mols of nitrogen flowing through the tower per unit time, while solid flow might be expressed as S, the pound atoms of calcium in all forms in the solid stream per unit of time. Defined in this way, both G and S are constant throughout the tower. The enthalpy of the gas and solid streams are now best expressed in terms of these key components. That is, the gas stream enthalpy H is expressed as Btu in the total gas per mol of the key component in the gas. Similarly, the solids stream enthalpy h is expressed as Btu in the total solid stream per pound mol (or pound atom) of the key component in this stream.

Jan 1, 1962

By Ralph W. M. Lai, D. W. Fuerstenau

In aqueous solution, an oxide surface is considered to consist of positively charged surface sites, MOH, neutral surface sites MOH, and negatively charged surface sites MO-. From the mass action law, equations for the distribution of these sites have been derived in terms of the hydrogen ion concentration in solution and the point of zero charge of the oxide. Experiments on the flotation of futile were carried out with sulfonates and amines which are collectors that physisorb, and with oleate, which is a collector that chemisorbs. Flotation response was found to correlate with the site distribution model. A similar correlation was found with published data on iron oxide potation.

Jan 1, 1977

By M. E. Gershon

The development of long-term plans and schedules for strip mines now faces many companies, especially those developing large properties in the West. The rule of mining the lowest strip ratios first, while delaying equipment acquisitions and recouping investment the fastest, sometimes creates the situation where stripping ratios are too high in the latter years of mining operations. A program concept taking life of mine return on investment into account is developed in this paper to optimize mine scheduling and equipment acquisition. In addition, quality considerations (heat content, ash, sulfur, and washability) can be considered by including the appropriate blending constraints to meet contract requirements.

Jan 1, 1984

By S. Terry, J. G. Munro

A unique feature of the recently dedicated pelletizing complex of Hamersley Iron Pty. Ltd. is the dry grinding circuit for the iron ore fines. This facility, located at Dampier, some 800 miles north of Perth, Western Australia, has a rated annual capacity of 2 million tpy of iron ore pellets. The Mt. Tom Price orebody, which supplies the pelletizing plant, is a massive deposit of high-grade hematite containing an estimated 500 million tons of ore averaging 64% iron. The main impurities are ferruginous shales that occur in bands of varying widths in the orebody. An average analysis shows 4.4% SiO2, 2.0% A12O3, 0.05% P and 1.8% LOI.

Jan 5, 1968

By Harry Bapty

LONGHOLE drilling with a heavy type percussion Leyner drill, jointed steel rods, and a tungsten carbide insert bit was investigated while drilling and working a quartz barite brecciated rock. Procedure and practice were developed and its suitability for tackling pillar and sill recovery proven and extended to regular stoping at Torbrit. Torbrit, as the name implies, is a contraction of the Toric property and the Britannia Mining & Smelting Co. Ltd., the former owners. This silver property, with minor amounts of lead, zinc, and rarer sulphides of little or no economic value, was discovered in 1916 from an outcrop in the Kitsault River, 18 miles north of Alice Arm Post Office, in the Portland Canal Mining District, B. C.

Jan 11, 1954

By D. M. Given

HOW much can the mine operator afford to spend on his coal burning boiler plant? The usual answer is as little as possible and still get the job done. Thus, attention must be focused on the spot where excessive costs are most likely to arise - the materials handling end of the job. Boiler plants consuming less than 30,000 tons of coal annually can be controlled to the point where costs for handling coal and ashes are under $1.00 per ton. There is a wide selection of coal and ash-handling systems that can be used in smaller boiler plants to provide labor savings and convenience required if management is to accept coal as fuel.

Jan 7, 1953

By E. G. Woodruff

Few authors of treatises and papers on engineering subjects hare given adequate attention to topographic maps. The statement applies especially to mining engineering in all branches. Even those who have discussed such maps have treated the subject only in a general way. Therefore it is proposed to outline in this paper a few of the uncommon yet important relationships which topographic maps and their by-product, structure-contour maps, have to modern methods of mining investigation and development when the facts depicted on such maps are properly interpreted. Topography, as suggested by the etymology of the word, means a detailed description of particular places. Written descriptions have been found less effective than the pictorial representations, therefore attempts have been made in various ways to picture the surface features of places. Lines and shading have been used, hachures drawn, and, finally, the contour topographic map. To a large extent this style of map is the result of the demands of engineers. It is designed to meet their needs far more than those of the man untrained in engineering. In fact,. the average man obtains a better idea of the topography of an area from the hachure system than from contour maps. Since the maps have been made chiefly for the use of the engineer, they ought to meet his demands on the one hand, and, on the other, should be used by him to the fullest extent. Such maps, when properly made, accurately portray a portion of the earth's surface and should present the topography better than a personal examination of the area without a map could present it, because the person making such examination views only a limited portion of the surface at a time, and estimates distances only roughly with his eye. Let the engineer consider carefully the fact that in many instances the topographic map is superior to a personal examination of the surface features of a property because the map is based on careful instrumental measurements, whereas the eye gives imperfect data because it can be used merely for the estimation and

Jan 1, 1914

By W. J. Carlson, I. Iwasaki

A previous article reported a combination process for recovering both metallic iron and metallic manganese from the manganiferous iron ores of the Cuyuna Range in Minnesota.' In this process, the iron was recovered by direct reduction and magnetic separation and the manganese was recovered from the nonmagnetic tailing by leaching and electrolysis. The current efficiency during the electrolysis of manganese is quite low, in the range of 60 to 70%, due to the simultaneous plating of hydrogen.2,3 The parameters that affect the current efficiency are (1) the concentrations of the manganese ion and the ammonium sulfate buffer, (2) the effect of autoxidant, (3) temperature, (4) pH, and (5) current density. To study the plating characteristics of manganese metal.

Jan 1, 1969

By G. W. R. Kuzyk, John D. Smith

Tantalum Mining Corporation of Canada Limited has been mining tantalum ore from the Bernic Lake pegmatite dyke since 1968. The shallow nature of the dyke and relatively high strengths of the various rock types led to the choice of a room and pillar mining method. Rock mechanic studies have indicated that the original pillar dimensions of 50 feet x 50 feet are conservative for existing rooms. Therefore, a plan to reduce the size of pillars using rock mechanics instrumentation to monitor the resulting stress on pillar remnants and stope backs was devised. The paper describes the test work done on the rock types within the pegmatite dyke. The use of Irad stress cells and extensometers in monitoring the stress in pillars is described. The actual results of the program to date are presented.

Jan 1, 1983

By J. E. Schaffer

Drilling activity in Ohio increased slightly in 1939. There were 1020 completions as compared to 910 in 1938. During the past six years the number of completions has varied little (Table 1). Oil production in Ohio has been gradually declining since 1896, when the peak production of 23,941,000 bbl. was reached (Fig. 1). Since that date production has slowly declined to an estimated production in 1939 of 3,144,134 bbl., the lowest in 53 years. This total production is divided approximately into the following grades of crude oil: Pennsylvania, 1,185,456 bbl.; Corning, 1,261,615 Flg 1. bbl.; Lima, 578,500 bbl.; Lodi, Based on figures of U. S. .Bureau of 104,740 bbl.; Cleveland, 13,823 Mines and Oil andGas Journal bbl. Table 2 shows the prices paid for the various grades of crude oil.

Jan 1, 1940

By J. E. Schaffer

Drilling activity in Ohio increased slightly in 1939. There were 1020 completions as compared to 910 in 1938. During the past six years the number of completions has varied little (Table 1). Oil production in Ohio has been gradually declining since 1896, when the peak production of 23,941,000 bbl. was reached (Fig. 1). Since that date production has slowly declined to an estimated production in 1939 of 3,144,134 bbl., the lowest in 53 years. This total production is divided approximately into the following grades of crude oil: Pennsylvania, 1,185,456 bbl.; Corning, 1,261,615 Flg 1. bbl.; Lima, 578,500 bbl.; Lodi, Based on figures of U. S. .Bureau of 104,740 bbl.; Cleveland, 13,823 Mines and Oil andGas Journal bbl. Table 2 shows the prices paid for the various grades of crude oil.

Jan 1, 1940

By P. G. Mason

The upswing in the price of gold in 1979 prompted renewed interest in the Mercur gold property by Getty Oil Company, owner and operator, and Gold Standard Inc. of Salt Lake City, Utah, currently retaining a 15% net profits interest. Extensive geological exploration work resumed to delineate the ore reserves, and metallurgical test work was initiated under the direction of A.H. Ross & Associates. This led to the development of an aqueous pressure oxidation process suitable for treatment of the refractory ores. Subsequent geostatistical studies revealed that the distribution of high refractory ore was less than previously estimated, and thus a higher return on investment could be realized if a direct carbon-in-leach process were used despite a sacrifice in overall recovery. This paper reviews the geological and metallurgical studies that led to this final process selection.

Jan 1, 1984

By Walter W. Fisher, Samuel Rudy

Secondary treated sewage effluent was substituted for normal process water in laboratory tests simulating froth flotation recovery of copper and molybdenum sulfides. Sewage effluent caused significant detrimental response in the flotation process. First, a voluminous, uncontrollable froth was generated, even in the absence of a frothing agent, that has little mineral carrying ability. Second, sewage effluent caused a small loss in copper recovery and a large loss in molybdenum recovery. The detrimental effects of sewage effluent on flotation were partially overcome by tertiary treatment of the effluent by activated carbon adsorption and anion exchange. The frothing problem was significantly reduced after treating the sewage effluent by foam fractionation. Dilution of the effluent with normal process water resulted in a significant improvement in metal recovery. In addition, the large loss in molybdenum recovery was overcome by using a secondary collector in a combination reagent schedule. However, the secondary collector caused an appreciable loss in copper recovery.

Jan 1, 1979

By Rudolph G. Wuerker

WITH the growing complexity of ore dressing processes and the diversity of equipment, efficiency control has become increasingly important in beneficiation. In the case of iron ore dressing, there have been sporadic attempts1-3 to establish the optimum separation for various ores so that grade and recovery would be readily predictable. But no rigorous statistical analysis and graphical presentation of such tests could be found in the literature of this country. Tests Made with Iron Ores Expanding upon existing methods of plant supervision and efficiency control, an investigation was started in the ore dressing laboratory at the University of Illinois on the applicability of distribution analysis to iron ores. A sample of crude ore was obtained from the Ohio mine of Cleveland-Cliffs Iron Co. at Ishpeming, Mich., consisting mostly of alternating bands of hematite and siliceous gangue, both about ¼ in. wide. The ore was heavily coated with limonite, which often filled the cracks.

Jan 7, 1958

By George C. Reynolds

INTRODUCTION The overall importance of the minerals industry during the next 20 years was highlighted In "The Global 200 Report to the President" (Barney, 1982) in the following terms: "The industrial and agricultural processes that are taken for granted today would be severely disrupted of any one of dozens of critical minerals ceased to be available in dependable, reasonably priced supply. Supply in turn has become highly energy intensive and international In scope ...... because resources are not uniformly distributed geographically, political considerations (also) become an Important determinant of price and trade patterns." In attempting to determine Australia’s contribution of bauxite raw materials to the world of the future, this paper necessarily also concerns itself with the alumina and aluminium industry to which it supplles the raw material. It is an industry which is energy intensive, International in scope and heavily influenced by political considerations. The aluminium industry has shown a remarkably rapid growth during the past 20 years (Fig. 1).

Jan 1, 1982

By W. J. Taylor

IN making heating gas with anthracite coal for roasting ore during the past few years, I hare tried many forms of gas generators. So far, the most successful and satisfactory one has been what we call a fluxing producer, which is simply a small cupola or blast furnace, in which we charge with the coal, say, 30 or 40 per cent. of basic blast-furnace cinder, to unite, when melted, with the ash or earthy matter in the coal, and carry it off as cinder. The producer we have in use at Chester, N. J., has pore of the lines of a blast furnace than a cupola, the hearth being 24 inches diameter and 24 inches high. It then enlarges on an angle of about 25 degrees from a perpendicular to 4 feet, and then is drawn into 3 feet on top ; total height, 12 feet. We use one water coil-tuyere 12 inches above the bottom, and blow through a 11/2-inch nozzle. The depth of coal above the tuyere averages about 6 feet. The producer. is blown with

Jan 1, 1881

By R. Costantini

Long-distance transportation of solids by hydraulic pipelines holds promise of great economic benefits. In most mineral processing plants today, moving of solids in slurry-form by pipeline is commonplace. Yet in spite of this, the method is slow in being adopted on a broad scale for moving solids over distances of many miles. This is especially surprising in view of the successful realization of two daring ventures in long-distance solids pipelines in this nation within the last five years. One is the 72-mile long, 6-in. diam. pipeline of the American Gilsonite Co. which has been satisfactorily transporting 700 tpd of gilsonite from the mine at Bonanza, Utah, to the processing plant at Grand Junction, Colo., since April 1957. The other is the 108-mile long, 10-in. pipeline of the Pittsburgh Consolidation Coal Co., which has been transporting about 4000 tpd of finely crushed coal from the mine at Cadiz, Ohio, to the Eastlake Power Plant of the Cleveland Electric Illuminating Co. since January 1958.

Jan 8, 1961

By Joel J. Lloyd

The storage and retrieval of geological information is represented by a "Babel" of systems. If the energy and expense that is being expended is to be fully exploited by the earth science community, a common language and common practise is required. Interfacing, applicable in the crossover of scientific disciplines and of polyglot data collections, is neither practical nor economic in the handling of English language information. Whether a single input/output center or a locus of interlocking subcenters is established, is irrelevant. The capture of fugitive information and recapture of lost data is paramount. Existing national committees and international commissions are cognizant of the problem and are engaged with it. The time required to reach agreement may merely complicate the problem. It may prove necessary for a group of individuals to face up to the situation and take the indicated action -- facing the criticism that will probably fall on their heads. The cost of rectifying immediate mistakes may be far less than the delayed execution of a long studied plan. System designs are considered in terms of input elements and output products, various mechanical operating modes are presented, and the economics of organization and maintenance are discussed.

Jan 1, 1969

By John Nelson

AN OUTLINE survey of the economic outlook for the United States export trade in petroleum products resolves itself broadly into two general divisions; first, a consideration of our present position in this trade, and second, a discussion of the visible factors which promise to affect appreciable changes in the immediate future in that trade. The UNITED STATES PETROLEUM EXPORTS OF MAJOR PETROLEUM PRODUCTS 1925, 1926 and 1927 Gasoline, Naphtha, and Other Light Products 1925 1926 1927* Quantity (gal.) 1,286,787,796 1,784,154,802 1,851,494,190 Value $197,491,588 $263,199,938 $214,721,652 'Illuminating Oil, Kerosene 1925 1926 1927* Quantity (gal.) 885;136,041 924,680,979 827,162,280 Value $84,699,724 $100,352,877 $80,358,082 Gas and Fuel Oil 1925 1926 I 1927 Quantity (gal.) 1,365,358,988 1,449,688,394 1,815,130,464 Value.... ? $49,040,024 $45,354,108. .. $50,343,031 Lubricating. Oil 1925... ....1926 .. 1927 Quantity .(gal.) 402,572,584 388,767,055 403,369,512 Value $90,596,671 $86,414,621 $88,926,815

Jan 1, 1928