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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 C. Kunze

ABSTRACT Although closure sureties cover works that are carried out during the existence of a mining company, certain liabilities are not known when the surety is established and become apparent only in a late stage of the closure phase, or even after the site has been relinquished. This paper supports the concept that these financial risks lend themselves to insurance solutions. Making insurance for unknown liabilities mandatory while defining unambiguous legal conditions could create a viable market for insurance products, provide a sufficient statistical basis for the calculation of premiums, and reduce costs.

Jan 1, 2013

By Charles Camsell

If it were necessary to preface a discussion of the mineral position of the Empire by justifying one's interest in that subject, there are two points that at once suggest themselves by way of vindication. Tremendous Growth of MINERAL Consumption The first of these points has to do with the general question of the world's mineral consumption. Most thinking persons appreciate in a more or less vague way the vital rôle that has been, and is being, played by mineral products in building up the material side of our modern civilization. But, apart from that casual and almost subconscious appreciation, very few have any precise knowledge of the extent to which the growth and the operation of our vast present-day industrial structure has been made possible by, and only by, a tremendous increase in the consumption of mineral products of all kinds. The increasing use of minerals confronts us today at almost every turn. It does not matter in what direction we look-at the expansion and the change in transportation facilities, in the air as well as on land and on sea; at the increasing mechanization, not only in factory and mill but even in our domestic life; or at the constantly widening use of machinery for all phases of farm production-everywhere we meet the same phenomena of rapidly growing uses of equipment produced mainly from minerals. Without resorting to any tiresome statistics, a few figures may suffice to indicate with what enormous strides the world's mineral consumption has been advancing. The figures for recent years may be open to objection on the plea that, ever since the outbreak of the world war, conditions have hardly been sufficiently normal to give us trustworthy data-we have been living under extremes either of depression or of abnormal stimulation. During the last decade before the war, however, from 1903 to 1913, the world was moving along in a quietly prosperous manner; and we have figures, or at least reasonably reliable estimates, as to the growth in mineral consumption during that decade.

Jan 1, 1932

By M. R. Shahan, C. E. Seaman, S. E. Mischler, T. W. Beck

"Float dust deposits in coal mine return airways pose a risk in the event of a methane ignition. Controlling airborne dust prior to deposition in the return would make current rock dusting practices more effective and reduce risks of coal dust-fueled explosions. The goal of this NIOSH study is to determine the potential of open-air water sprays to reduce concentrations of airborne float coal dust (<75 µm diameter) in longwall face airstreams. This study evaluated unconfined water sprays in a featureless tunnel ventilated at a typical longwall face velocity. Experiments were conducted for two nozzle orientations and two water pressures for hollow cone, full cone, flat fan, air atomizing, and hydraulic atomizing spray nozzles. Gravimetric samples show that airborne float dust removal efficiencies averaged 19.6 percent for all sprays under all conditions. The results indicate that the preferred spray nozzle is operated at high fluid pressures to produce smaller droplets and move more air. These findings can be used to select sprays and design spray arrays to control airborne float dust over the entire longwall ventilated opening. INTRODUCTION Coal mining processes produce airborne dust that naturally deposits on the floor, roof, and ribs of mine airways. These fine dust particles, termed float coal dust when smaller than 75 microns in diameter, are deposited in return entries of coal mines and can be re-entrained by pressure waves induced by methane-air explosions (Rice et al., 1911; Nagy, 1981; NIOSH, 2006). These particles are also those most likely to participate in coal dust-fueled explosions, which can potentiate and propagate explosions resulting in extensive damage. In order to meet compliance requirements of at least 80 percent incombustible content in the composition of material deposited in mine entries (CFR, 2016), coal mines apply an inerting agent, specifically, rock dust (Harris et al., 2009). Should methane be present in the mine atmosphere, the required fraction of incombustible content is further increased by 0.4 percent for each 0.1 percent methane. The removal of airborne float coal dust (AFCD) prior to deposition is an approach intended to make current rock dusting practices more effective by increasing the proportion of inert material to combustible material, resulting in a lower risk of coal dust-fueled explosions. Water sprays are both effective and widely accepted as a method for controlling underground coal mine dust. In fact, water sprays are considered to be the most economical and technically feasible means of reducing dust concentrations in underground coal mines (Courtney and Cheng, 1977; Barker and Humphreys, 1996). Sprays are used in several ways to control dust in mining processes: inhibiting dust formation, immobilizing dust to prevent it from becoming airborne, and capturing airborne dust (Cheng, 1973). Reductions in airborne dust concentrations have frequently been attributed to inertial impaction between water droplets and dust particles, forming larger agglomerates which then quickly precipitate out of the airstream (McPherson, 1993). Inertial impaction activity is generally accepted as the major capture mechanism for airborne particles larger than 0.5 µm in diameter. It is this mechanism that is evaluated in this study."

Jan 1, 2017

By A. D. Garman

This paper presents one of a series of digests of foreign mining legislation and court decisions which is being prepared in advance of a general report relative to the right of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of the laws of Bolivia has been prepared from the best available information in Washington, but is released subject to correction and amplification, if necessary, by the proper American diplomatic and consular officers to whom it is being referred through the courtesy of the Department of State. SYNOPSIS OF LAW All useful substances of the mineral Kingdom belong originally to the State. The soil and subsoil are regarded as two distinct parts, the latter extending indefinitely in depth (Art. 2). The subsoil is under the dominion of the State, which may either abandon it to common use, grant it gratuitously to the owner of the soil, or alienate it, in return for an annual fee, to any individual or association that applies for it. (Art. 1-3.)

Jan 1, 1929

By A. J. Keast

This circular is one of a series dealing with the exploration, equipping, and development of mining properties, prepared and published by the United States Bureau of Mines in cooperation with various mining and exploration companies in the United States and Canada. This series of papers will supplement an earlier one which covered the methods and costs of mining and milling at a large number of producing mines. The present paper describes the exploration, equipping, and developing of a group of 18 claims remote from rail transportation, and the transport of equipment and heavy supplies for a distance of 120 miles by tractor over ice and winter roads, and of men and lighter supplies by airplane.

Jan 1, 1933

By Walter Nelson

Considerable thought and discussion had been devoted toward provision for increased milling capacity at the Allenby concentrator of The Granby Consolidated Mining, Smelting and Power Company operations as early as 1940. During the war, plans for the installation of an additional grindi.ng unit were formulated but were not carried out. It took considerable time after the war to prepare the mine again for its highest rate of production since, with the scarcity of men, development work had been sacrificed in favour of maximum ore shipments. In order to prepare for the expected competitive market in copper, the matter of increasing the capacity of the concentrator was again given serious attention. As ore became available in the mine and the output of the mill was increased, limitations for a satisfactory recovery were observed, due to the overloaded condition of the classifier units at the higher tonnages. From a metallurgical standpoint, the ore from the Copper Mountain mine had always been difficult to treat on account of the finely disseminated character of much of the mineralization and the difficulty of grinding to the desired fineness. This trouble has become aggravated with time as an increasing amount of wall-rock has diluted the ore and lower grade orebodies have been mined. It therefore has been, and is, the practice at the concentrator to maintain the maximum amount of reduction in size of material fed to the flotation units as is possible for the daily tonnage to be milled. This means that all the grinding units are operated for the maximum possible time, and that the classifiers are regulated to return as much feed ?as possible to the mills. The number of tons to be milled for ?the day is determined by the concentrator superintendent after ascertaining the availability of ore from the mine, the condition of the concentrator ore bins, and the need for repairs in the rolls plant. In order to maintain the tonnage des1red, hourly estimates are made of the rate of grinding by weighing the amount of ore contained on one foot of each of the belts conveying the feed to the various ball-mills, and adjustments are made accordingly.

Jan 1, 1950

By M. J. Hrebar

In the summer of 1990, a study was conducted to document large tractor (i.e., Caterpillar Dl1N) utilization in surface coal mining. The tractors were found to be utilized as primary production machines and in combination systems with blast casting and draglines and blast casting and excavator/truck systems. In addition, dozers were used to prebench ahead of a primary dragline system. The study also established ranges and averages for Dl1N operating costs and mechanical availability. Based on simulated production of various tractor dozing applications, the potential for low cost coal stripping was suggested (Hrebar, 1991). A follow-up study, also funded by Caterpillar Inc., was conducted in the summer of 1991 to determine actual production rates in two dozer stripping applications. These actual production rates would then serve as a foundation for estimates of stripping costs. This paper presents the results of the studies in a contour and a cast application.

Jan 1, 1992

By H Jones

Closure cost estimates may be generated at any stage of a mining operationÆs life; commencing with the initial prefeasibility studies and continuing through to the final decommissioning cost estimates. However, not all mine closure cost estimates are necessarily the same. Cost estimates will vary depending on the purpose for which they are prepared, the organisations requiring or undertaking the estimate and the stage of the mining operation. Different organisations can legitimately arrive at disparate cost estimates for closing the same mine because the organisations have different reasons for requiring the estimates. Another, equally valid, reason for potentially wide variations in cost estimates by different organisations on the same mine site is the different definitions of æclosure costsÆ used by different estimators. This paper considers the different approaches by different organisations including operating companies, government authorities and financial organisations and uses a hypothetical example based on practical experience to illustrate some of these differences in estimation methods.The paper suggest that a more consistent approach to closure cost estimating in the Australian mining industry would assist mining companies, governments, the accounting industry and the broader community to better understand this complex component of mine planning. One possible approach to closure cost estimating is briefly outlined.CITATION:Jones, H, 2012. Closure cost estimation - All things to all men?, in Proceedings International Mine Management 2012, pp 115-124 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By R. L. Loofbourow

Reasons for reexamining underground mining include: 1. The assurance that more deep deposits of useful minerals will be found. 2. The existence of deeply covered deposits of industrial minerals near large markets where quarries are becoming depleted or are lacking. 3. Surface property values, zoning and other limitations on open pit mining. 4. Expectation that underground space will be increasingly used for transportation, power plants, storage and similar purposes. 5. The improvements which have been made in underground mining. During the last three or four decades many changes and improvements have been made underground. All underground construction and mining has benefitted to some extent but the effect on the productivity of labor employed with some methods- has changed little and the use of these methods has declined. Productivity of labor in other methods has increased substantially. The relative usefulness of mining methods has changed and a vital industry, bituminous coal, has been returned to health. In this paper, consideration is limited to nine methods used with high productivity during the period under review. These methods are not necessarily better than others but they may be considered the prime methods in the sense that, in our economy, many, low grade ores, coal and the principal industrial minerals could hardly be produced by less productive means.2 Although most of the examples cited are from mining as such., the first four methods discussed can be used for the construction of stable excavations of various&apos; shapes in sound rock.

Jan 1, 1967

By F. R. Erick Mulder

"AbstractTwo bottom-hole samples have been taken from two new completions in the Turner Valley field, Royalite Lowery No. 8 on the west flank and Royalite No. 73, which was deepened into a lower fault block, on the northeast flank. From the bottom-hole oil of Royalite Lowary No. 8 a synthetic sample was prepared to simulate the original fluid in the reservoir, saturated at the gas-oil contact conditions. The sample from Royalite Lewery No. 8 has been shown to be the original fluid present at this well and represents the oil phase near the oil-water contact in• the reservoir. Complete chemical analysis, P.V.T., and viscosity data have been obtained on these reservoir fluids, which represent the range of saturation from the gas-oil to the oil-water contact in the Turner Valley oil structures. Sampling techniques and the application of the analytical data to reservoir conditions and field operations are discussed. Super-compressibility curves for an average separator tail gas have also been prepared. These data have not been available before. They will be of fundamental value in futu.re reservoir engineering studies of this field and will also serve as a guide in determining operating practices."

Jan 1, 1950

By M. S. Enders

The McDonald deposit is a volcanic-hosted epithermal gold resource that is estimated to contain 251,000 kg of gold in 375 Mt of ore at an average grade of 0.7 g/t gold. Phelps Dodge exploration geologists, working for the Seven-Up Pete Joint Venture, discovered the deposit in 1989. By the end of 1992, 494 drill holes for over 113,000 m of drilling, bulk sampling, soil geochemistry, geophysics, metallurgical testing, engineering, and environmental studies had been completed to support feasibility studies. The discovery of McDonald required vision, persistence, and commitment of everyone from the geologist on the drill rig to the senior management of the company.

Jan 1, 1995

By J. W. MacDonald

Two coal mine shafts recently completed in Franklin County, Ill., afford experience and accomplishment to warrant review, These shafts provide access to a tract with a potential recovery of one hundred million tons. This work provided the initial sinking by other than a contractor&apos;s organization since 1918. Four additional shafts required during the interim were sunk under contract arrangement with others. Supervisory contact and inspection afforded experience to govern planning and conduct of the recent work.

Jan 1, 1960

By Yuliy Rubinstein

"The paper presents a analysis of the history and the trends of development of flotation apparatus. The laws of their evolution are stated and the place and role of column flotation are indicated. It is demonstrate development and different design of column apparatus. The major parameters of column cell such as diameter and height are discussed. Options are proposed on optimization of hydrodynamic characteristics of columns with large-capacity cells. High efficiency of columns with cell height of 4-6 m is shown on examples of coal preparation. A new generation of multi sectional column cells has been developed. In the cells are zones with different aerohydrodynamic parameters: combined in the machine are co-and counter- counter flows of phases. The transition from single-chamber column to multi-sectional apparatus makes it possible to create favourable hydrodynamic and aeration regimes in each section of the column dependent on the pattern of material distribution by floatability. Efficiency of application different designs column apparatus uses shown on the example of enrichment of various non-ferrous metals ores and coal. The principles of mathematical simulation of the flotation process are developed. A scaling-up procedure for column cells was based on flotation macro- and micro- dynamics simulation.INTRODUCTIONColumn flotation is considered to be one of the most significant achievement in the field of mineral processing in the end of last century. We cannot but agree with this statement but would like to understand what underlies this success. History of the flotation column can not be considered in isolation from the development of flotation apparatus on the whole. It can be argued that the first attempt to switch from oil flotation to the use of bubbles during flotation was performed Bessel brothers in 1877 (Berlin patent 42 class 22, July 2) and in 1886 (Berlin patent 39,369 May 12). According to these patents, the crushed ore was mixed with oils , hydrocarbons and water. Then the pulp received in this way was heated up to boiling . Air bubbles and steam formed during boiling facilitate the flotation of ore particles coated with oil (first patent) or bubbles been generated by the reaction of lime with acid (second patent). The evolution in the design of the flotation apparatus incorporates the following key stages. Further development is connected with the Francis Elmore’s idea to use gas bubbles received at water electrolysis (UK, 13578; 1904). This method was not introduced then, but much later, in our time and on the essentially new technical basis it found a use for sewage treatment (electroflotation). Gas bubbling under vacuum patented also by Elmore (UK, 17816; 1904) obtained a practical use. It should be noted that the method did not lose its importance till now. The design of the camera has been surely optimized (Glembotskii etal, 1963). A year later A. Macquisten (UK, 26712) developed pressure (compression) flotation. Thus, the H.Sulman, H.Picard, D. Bell’s (US, 853120, May 29, 1905) basic patent and the adjoining T. Goover’s patent 1910 (US, 953746) formed the basis of the first and most important element of modern flotation: flotation with air bubbles sucked in from the environment. In 1914, J.Callow received a patent for on an apparatus where air was sparged through the porous false bottom of the cell ( US, 1104755). Woolen fabric folded four times was fixed on a perforated metal frame to be used for air sparging (Gaudin, 1932). The following year Durrel created the prototype of the injection (ejector) apparatus. The jet aerator made it possible to significantly reduce the size of the bubbles, in comparison with the filter cloth. An apparatus with slurry pre-aeration in an airlift prior to feeding into separation cell was developed Wagner in 1917 (US, 1235083). And finally, the first column apparatus with a counter-current of slurry and air was developed by M. Towne and S. Flynn in 1919(US, 1,295,817). ("

Jan 1, 2018

By Joel K. Waterland

The Homestake Mining Company at Lead, South Dakota is one of the few remaining gold properties still in operation, in this country. The mine is relatively deep, with a bottom production level of 4250 feet, and a bottom development of 6200 feet. 4, 800 tons of ore are produced daily from three rather large, but inconsistent ore bodies; the dip of which is easterly at about 72 degrees, and the plunge to the south is about 30 degrees. The ore is, for the most part, a chlorite schist with large veins of secondary quartz and cummingtonite schist The ore is not continuous in any direction, but is localized at the ridges of the very intricate system of anti clinal folds. This property has been in active production since its establishment in 1876, except for a period during World War II. The incentive, or contract pay system, has been a gradual process that has been developed by the trial-and-error method down through the years. In looking over the old records, hand-shoveling was paid on an incentive basis as far back as 1916. Since this time, the contract system has grown until it now includes almost all types of underground work - except haulage and maintenance work

Jan 1, 1960

By J. H. Howard

The purposes of this report are to summarize the findings of the Committee on the Challenges of Modern Society Non-electrical Project (a working committee of the North Atlantic Treaty Organization) and also, thereby, to provide an introduction and review of the current situation regarding non-electrical applications to those who are interested in the subject.

Jan 1, 1975

By J. H. Ambrose

Introduction The copper smelter of the Hudson Bay Mining and Smelting Company, Limited was constructed to handle the concentrates produced by the concentrator, the residues from the zinc plant, concentrates from Sherritt-Gordon Mines, Limited, and other custom material that might be available. Construction work was started in 1929 and the first concentrates were smelted in November, 1930. From that time until June, 1931, the operations were more or less of an experimental or tuning-up nature. In designing the smelter, it was believed the following tonnages would be available for smelting per day: Copper Tons Content H. B. M. & S. Co. concentrates 331 14.0 per cent H. B. M. & S. Co. zinc plant residues 77 2.5 per cent Sherritt-Gordon concentrates 200 20.0+ per cent Consideration was given to wet-smelting the charge, but, in order to give greater flexibility to the operation, it was finally decided to roast the concentrates before smelting. Briefly, the smelter equipment consists of three Nichols-Herreshoff roasters, one reverberatory furnace, two Peirce-Smith converters, a Walker casting wheel, and a four-unit Cottrell plant, two units&apos; for the roaster gases and two for the converter gases. A general plan of the smelter is shown in Figure 1. Prior to the commencement of smelter operations, a stockpile of about 9,000 tons of concentrates had been built up by the concentrator and the old pilot-mill. The zinc plant was in operation, but the equipment for drying the residues at the smelter had not been completed. Sherritt-Gordon did not commence their shipments of concentrates until April, 1931. The only flux available was barren sand from a pit ten miles south of Flin Flon, adjacent to the railway. Several small deposits of metal-bearing siliceous ore had been discovered in the district, but none of these were sufficiently large to be considered as a source of smelter flux. At the beginning of March, 1931, the entire stockpile of concentrates had been consumed, and available tonnage for smelting was limited to the daily production of the concentrator.

Jan 1, 1935

AT the Annual General Meeting held in Winnipeg last March, the whole of one of the technical sessions was devoted to a special Symposium on Geological Investigations in Canada, introduced by a paper entitled The Geological Survey (lî which had been specially prepared by Dr. G. A. Young, Chief Geologist of the Survey, and had been published in the February BULLETIN, prior to the meeting. Geologists from each of the provinces contributed to the Symposium, including directing officials of the geological divisions of provincial Departments of Mines, representative geologists from the Universities, and company and consulting geologists. Space, unfortunately, does not permit publication of a complete record of the proceedings,_ or even inclusion of all contributions to the discussion. The following summary, however, gives what is believed to be a fair cross-section of the opinions expressed by representatives from each Province. The Symposium resolved itself largely into a discussion as to how the Geological Survey and the several provincial bureaus or divisions of geology could co-operate most effectively in the important task of carrying out geo-logical investigations, with avoidance of duplication of work and waste of effort, and, so far as broad principles are concerned, there was remarkably close agreement among those participating in the Symposium as to how the various types of investigation should be allocated as between the Federal and Provincial organizations. Briefly, the concensus was that the Geological Survey can render the most effective assistance by conducting reconnaissance investigations, with mapping at 4 miles to one inch, leaving to the provincial organizations the more detailed, and hence more local, studies and mapping at larger scales. There was general agreement that the preparation of base maps, essential to systematic geological investigation, is a service devolving upon the Federal Government.

Jan 1, 1940

By Marline J. Veesaert

Urban quarries offer one of the greatest opportunities for profit in non-metallic mining with limited financial risk IF properly evaluated, planned and developed to meet market needs. Location, with respect to market, is the prime consideration. Geologic considerations and quality of rock are nearly as important. Cost factors and return on investment (ROI) are the principal financial considerations. Risk of capital is determined by weighing all factors that should be considered and how well judgements are based on information acquired. It is a simple, true axiom of business that an investment must be founded on amount of capital required with its expected return plus profit, expertise required to operate and time involved. Urban quarries generally offer excellent stone product market opportunities. Costs of land with mineral containment and processing operations are much greater than in rural areas. Environmental problems have become increasingly severe. Competition from other quarries in the market area is usually directly proportional to the profit attractiveness. Risk of capital (initial, developmental and operational) can be evaluated and reduced only by thorough analysis of the entire situation. Time and money expended on planning and preliminary investigations probably represent the most productive investment of available company resources.

Jan 1, 1977

By Takeshi Nagano

Copper pyrometallurgy in Japan has experienced quite fundamental changes in last fifteen years. The severe environmental restriction coupled with increase of energy costs accelerated the development work of the new continuous process in Mitsubishi Metal Corporation. After several years of pilot plant test work the commercial plant was put into operation at Naoshima Smelter in 1974, the design capacity of which was 4,000 tonnes of copper per month. Many modifications and improvements have been incorporated into the process and 7,200 tonnes per month of copper production was achieved in 1983, proving that continuous process was much more economical than conventional process. It is now possible to design and operate the continuous process in wide range of capacity. This paper will review the process and describe the progress of the process in these 10 years. 311

Jan 1, 1985