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By Harry Perry

By 1980, the free world's need for economic sources of energy is expected to double. As a result, there will be a tremendous potential for all energy sources working together to supply the demand. For coal to continue its dominant role as a low-cost energy source, means must be found for it to meet the challenge of nuclear power and to overcome obstacles placed on its use by air and water pollution regulations. As the more limited reserves of gas and oil diminish, economic ways are also required for converting coal to synthetic liquid and gaseous fuels, and to chemicals, thus resulting in optimum utility of the most abundant low-cost fuel resource. The means for accomplishing these ends can only come about by a vigorous research and development program. Successful efforts by industry and government working together, both in America and abroad, will assure the continued use of coal to meet the world's energy demands. This paper discusses the emerging patterns of energy sources throughout the world and the role that research and development on coal will play in supplying future energy requirements.

Jan 1, 1967

By M. Courtin, D. Berthelot, M. Haggis, D. McClarty, R. Payne

Over forty years of uranium mining in the Elliot Lake region of Ontario (1956–1996) has resulted in the production of over 300 million pounds of uranium. With the completion of mining activity, Rio Algom Limited and Denison Mines Limited are utilizing progressive environmental technologies and management systems to reduce and manage the environmental risks associated with the 150 million tonnes of potentially acid-generating tailings in nine regional waste management areas. Water covers designed to reduce oxygen entry and, thereby, significantly inhibit acid generation, have been applied at six of the sites with the Quirke site serving as a demonstration site for the Mine Environmental Neutral Drainage program. All five of Rio Algom Limited’s effluent treatment plants are monitored and controlled from a central control station utilizing a Supervisory Control and Data Acquisition (SCADA) system based on “Fix Dmacs” technology. Scheduling, auditing and reporting of plant operating and environmental monitoring programs for the entire watershed are controlled utilizing the Regional Environmental Information Management System (REIMS). Proper application of these technologies and management systems facilitates delivery of cost-effective environmental monitoring, care and maintenance programs at these sites and provides tools to demonstrate compliance with all environmental performance criteria.

Jan 1, 1999

By R. J. R. Welwood, F. J. Grebenc

"Brunswick Mining and Smelting Corporation Ltd. (controlled by Noranda Mines Limited) operates two lead-zinccopper- silver mines approximately 20 miles inland from Bathurst, N.B. The principal No. 12 orebody is mined by underground methods; the second, the No. 6 orebody (6 miles away), is recovered by open-pit mining. No. 12 underground operations ar•e in two parallel massive sulphide orebodies about 400 ft apart, dipping at 75 to 80 degrees and plunging almost vertically. The initial mining phase involved longhole open stoping from the 1550 level to the crown pillar, with main levels at 150-ft intervals and sub-levels between at 75 ft. Stope dimensions average 120 ft long, 100 ft wide and 400 ft high, with alternate rib pillars as well as sill and crown pillars. Initially, ore was transferred through scram drifts below each stope by means of 125-hp electric slushers and 72-in. folding scrapers, being delivered to gravity ore-pass collection •systems feeding a primary jaw crusher below. Later, track and trackless drawpoints were utilized below most longhole open stopes and pillars. Rib pillars were recovered by longhole methods, with large blasts into a central slot and undercut, after adjacent stopes had been filled. Waste-rock stripping from No. 6 open pit has been supplied to No. 12 stopes as backfill, by means of gravityfill raises.In 1968, the decision was made to mine the remaining ore zones by mechanized cut-and-fill methods, utilizing Load-Haul-Dump equipment. Currently, approximately 60 per cent of No. 12 mine production comes from mechanized cut-and-fill mining. As before, backfill is supplied from No. 6 open pit stripping waste rock, which has been crushed to minus 6 in. The ultimate objective is to supply virtually all production requirements by mechanized cut-and-fill techniques. The No. 6 open pit, which commenced production in 1966, covers an area of 1,500 by 1,200 ft, equivalent to 41 acres approximately. Ramp roads are graded at 8.5 per cent. Each mining bench is 36 ft high and the ultimate pit will consist of 14 benches for a final pit depth of 504 ft. Present depth is 180 ft."

Jan 1, 1971

By S. K. M. Chao

The increasing demand for large volumes of relatively low-cost cement has resulted in the need for an equally low-cost high-volume means for transporting that cement. It has been estimated that 20% - 25% of the total cost of cement to the buyer represents delivery expenses from the mills. For instance, during the 1972 cement shortage in the Southeastern region of the U. S., bid prices for a ton of cement delivered increased to $45 compared to $20 average at mill price, i. e. , F. O. B. plant. Much of the increase was caused by the anticipated higher cement shipping costs for longer hauling distance. The exceptionally high bid price, of course, was not the price quoted by the successful bidder. Thus, clearly, cement is not a marketable commodity unless it can be economically transported to the consumer.

Jan 1, 1975

The Bureau of Mines is establishing design criteria for effective roof support systems and is developing technology to improve mine planning and design. Geologic studies, surface and underground mine monitoring, and laboratory evaluations were conducted. The seven papers in this proceedings Information Circular present results of several investigations. Addressed are problems existing in both longwall and multiple-seam mines. Discussions include the effect of dewatering at a longwall mine site in the Pittsburgh coal seam and the effect of chain pillars on subsidence. Other results are measurement and characterization of longwall rock mass movement and an integrated design for stability in multiple-seam mining.

Jan 1, 1987

By Renpei Yoda

An investigation was conducted to develop columbium alloys with e1evated-temperature strengths higher than those exhibited by more common commercial columbium alloys, and attention was given to improving the oxidation resistance and ease of fabrication. Additions of carbon, aluminum, and chromium were made to some columbium-base alloys, and their effects on workability, recrystallization, oxidation resistance, and mechanical properties at elevated temperatures were explored. The additions were made to take advantage of (1) solid solution strengthening, and (2) precipitation hardening. Three alloys displayed good high-temperature properties with relatively good oxidation resistance at 1,000° C, and tensile strengths from 26,000 to 32,200 psi at 1,400° C. When the properties of these alloys were compared with those of commercial alloys, B-66 and FS-85 (1),4 the outcome was favor-able for the alloys studied in this investigation.

Jan 1, 1967

By A. J. Martin, M. J. Peoples, D. J. Adams, A. Opara

"The weathering of coal mine waste rock releases iron, calcium, sulfate and associated trace elements like selenium (Se). Nitrogen species are also found in association with coal-mining drainages mainly due to the leaching of residual blasting compounds. Elevated concentrations of Se are a ubiquitous occurrence in coal-mining environments in British Columbia. A major concern with waterborne Se in British Columbia is the potential for its bioaccumulation in aquatic food chains.Treatment to remove Se from coal-mining waste waters has proven to be challenging for conventional water-treatment technologies. Compounding this challenge, many streams are characterized by high flows and low selenium concentrations. Conventional membrane and ion exchange treatments produce concentrated brine streams that are difficult to treat or require disposal. Conventional biotreatment systems use excess nutrients to provide the required electrons to compensate for inefficient and variable electron availability, as well as to adjust reactor chemistry.This paper's electro-biochemical reactor (EBR) technology provides a controllable and consistent supply of useable electrons to the microbes directly at a low voltage potential (1-3 V) and low current. In this manner, the EBR technology overcomes the shortcomings found in conventional systems, as it reduces the required nutrient addition and provides a more controllable, efficient, economical and robust biotreatment system. Additionally, the EBR process does not produce excess solids or biomass; therefore, solids management post-treatment is not required.Laboratory EBR bench-scale and on-site pilot-scale systems were used to treat five British Columbia coal-mine waste waters; influent Se concentrations ranged from 35 µg/L to 531 µg/L. Se treatment targets for the tested waters ranged from 5 to 10 µg/L. Mean Se concentrations in EBR effluents ranged from 0.5 µg/L to 1.4 µg/L, while reducing sulfate concentrations. The test data demonstrate that the EBR technology is an effective Se removal option for British Columbia’s coal-mining waste waters.IntroductionSelenium in Mining. Selenium (Se) is a naturally occurring trace element, which is an essential nutrient in small amounts (Thompson and Robinson, 1980; Brown and Arthur, 2001). However, it is also toxic to aquatic life, birds, and humans at very low concentrations. A major concern with waterborne Se is the potential for its bioaccumulation in aquatic food chains, resulting in acute and/or chronic toxicity to fish, water birds and amphibians (Besser et al., 1996; Conley et al., 2009)."

Jan 1, 2015

By T. A. Rickard

The function of a preposition is to show the relation of one thing to another; it is necessary therefore for the writer to select the preposition that indicates the particular relation, otherwise he will fail to express himself clearly. Is it against common sense' to suggest that a Government is justified, morally as well as constitutionally, in preventing the decay of an industry by insisting upon the amalgamation of the prosperous with the needy? All these seven prepositions are used correctly. With the first dredge introduced in Russia, of Werf Conrad, Haarlem, make, this method of alluvial dining became important. Here the prepositions "with", "in", and "of" are used wrongly. He means: "This method of a1lu;ial mining sprang into importance shortly after the first dredge, made at the Werf Conrad, Haarlem, was introduced into ;Russia." The statement itself ii not true, but for that I am not responsible. Once, while I was serving with him, we were frozen in out of sight of land in the Gulf of Pichili in the North of China. Admiral Fisher wrote thus. He has used nine prepositions in making this brief statement. The sequence of three prepositions "in out of" is particularly awkward.

Jan 1, 1931

By Griffith. F. E., Glei

"INTRODUCTION For many years protective grounding of electrical equipment has been advocated as a means of safeguarding equipment against damage and of minimizing shock hazards to persons. Several codes are in effect covering in considerable detail the items to be observed in obtaining effective grounding in and about industrial plants. Although the coal-mining industry does not have a comprehensive code of its own covering the grounding of electrical installations, a number of States and individual coal-mining companies have issued codes, standards, or rules that include certain requirements with reference to grounding. As early as 1916, 4/ and again more recently, 5/ the Bureau of Mines recommended grounding, particularly as a means of preventing shock to men working on or around electrical equipment.It is common knowledge among electrical engineers of public utility and mining companies that connecting a wire from the frame of a machine to a rod or pipe driven into the earth does not necessarily assure desired protection of surface equipment. In fact, it has often been found necessary to use several interconnected rods and to treat the surrounding earth with salt or other chemicals before the connection to earth would have sufficiently low resistance to give satisfactory results. Even these expedients have not produced the desired results in some localities. It has also been found that ground connections initially having a low resistance may attain high resistance during some seasons of the year. In spite of such difficulties with surface equipment, it has sometimes been assumed that a mining machine resting on the floor in a coal mine is grounded by virtue of its contact with that floor. It has also been assumed by persons endeavoring to comply with grounding requirements that a peg or rod driven into the mine floor would provide a sufficiently low-resistance contact with the earth to be satisfactory as an electrode for connecting the grounding wire from frames of equipment. That both assumptions may be wholly untrustworthy has been proved by the authors in actual tests with underground machinery."

Dec 1, 1943

By L. C. DeCory

"Concrete is a common denominator to the building process and portland cement is an integral and necessary component of concrete. The cost of portland cement is nominal and its cost comprises, in most instances, a small portion of the total cost of ""put-in-place"" concrete.The domestic demand for portland cement in Canada is projected to be slightly less than 11 million short tons in 1980. In order to achieve this projected goal, stabilization or lowering of the cost of put-in-place construction is necessary. This enhancement of the cost of building can be achieved by:(1) improving the building process;(2) refining and improving design techniques; and(3) developing improved and economical concrete products.Some of the techniques and materials that will lead to building cost stabilization include systems building in its broadest sense, slipforming, precasting, prestressing, computer design, lightweight aggregates, fibrous concrete and integration of building components."

Jan 1, 1973

By T J. V Duffy, L H. D Siahaan, P G. Albert

G-ResourcesÆ Martabe Mine in North Sumatra, Indonesia, is a US$700 M world-class and world-scale operation in a country which, with a few notable smaller scale exceptions, has had no significant hard rock mining development in more than ten years.The mine was commissioned in the middle part of 2012 and poured first gold on 24 July. At full production Martabe will produce 250 000 oz/a of gold and 2 - 3 Moz/a of silver at cash costs in the lowest quartile. The mine location is on the west coast of North Sumatra, which experiences annual rainfall of 4 m with no notable dry season, adjacent to seismically active fault zones, and relatively close to a rural community of 31 000 people with no significant industrial experience.The management team has successfully forged strong links with the various government departments and levels in Jakarta, North Sumatra Province and the local Regencies; developed long-term relationships with the various community groups within the local district of Batangtoru to build a sustainable social licence; has dealt with the physical and environmental challenges presented by the project location, and has successfully raised more than US$900 M over a period of three years for the original acquisition then the development of the project.Whilst in its infancy of operation, the mine is set up to deliver a long-term sustainable future for the company, the shareholders, and the people of Batangtoru and all stakeholders generally. The quality of the project execution and commitment by the company will ensure that maximum value can be delivered from Martabe, not just for the current mine life but from the significant exploration potential that exists on the large tenement area that the company has access to for 30 plus years.This paper will deal with the physical challenges associated with the design, the Indonesian government regulatory requirements for mine development, the social aspects of building a world-class project in a developing area, the in-country commitment necessary for any project development anywhere in the world and the successful funding arrangements for the mine development.CITATION:Albert, P G, Siahaan, L H D and Duffy, T J V, 2012. Building AsiaÆs latest hard rock mine, in Proceedings International Mine Management 2012, pp 189-204 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By C. H. Burgess

ON June 5, 1947, Secretary of State George C. Marshall in a speech at Harvard University outlined a plan for the economic recovery of Europe. The plan contemplated that the United States should provide assistance which would enable the European nations better to help themselves and to help each other to reconstitute from their war-torn lands conditions which would make possible decent standards of living.

Jan 1, 1950

By Frederick W. Lee

List of contributing editors of Geophysical Abstracts:

Sep 1, 1932

By S. A. Falconer

Much attention and publicity has been given, during recent years, to grinding, classification, flotation, and thickening. The various technical papers, and symposiums held to discuss these important phases of milling, have contributed to a better under- standing of the fundamental principles and operating variables involved. Another important part of milling- to the flotation operator-is a treatment step to which frequently too little attention is given-" conditioning," or the treatment the ground mineral pulp receives before it enters the flotation machines. Conditioning" is a hackneyed and frequently misused term, commonly employed to describe the pretreatment of surfaces of minerals in ore pulps or mill pr6ducts prior to froth flotation. In general, such pretreatment is for the purpose of changing the flotation characteristics of these mineral surfaces to enable them to respond in some desired predetermined manner when subjected to flotation. Taggartl states that the function of conditioning is "either to insure selective collector coating of one mineral species while another species is not; or to take such steps as will compensate for departure there from."

Jan 1, 1949

By Stig Premfors

Lamco Joint Venture is operating a Dravo Pelletizing machine to produce pellets from the natural slimes of an earthy hematite ore. The grate area of the machine 3.3 x 106 m equal to 350 m2 (3800 sq. ft.) and the installed fan capacity is 8200 HP. The limiting factor for production is normally fan capacity. This means that the processing fans can not pull the additional air (i.e the additional calories or BTUs) through the bed which would be required for increased production. A way to increase production without major modifications is to supply the additional calories needed for increase production by adding coal to the pellet feed. After successful laboratory tests following method of coal addition has been chosen and the following results have been obtained. 1. The ground coal is added to the slurry prior to the filters and the rotary dryer. 2. By adding 0.6% coal, an increase of about 15% in production rate has been obtained. 3. No significant changes of metallurgical properties have been observed (i.e. tumbler index, compressive strength, ferrous iron content, reducibility, Linder degradation and swelling). 4. No unexpected operation problems have been experienced. The pellet discharge temperature increases and is the limit for how much production can be increased by coal addition without making plant modifications.

Jan 1, 1971

By D. A. Cowen

Toll and custom treatment of base metal concentrates have been performed for decades as mines and concentrators are developed distant from capital and, energy-intensive smelting and refining facilities. Commercial treatment terms have been developed and refined for over a century, and are negotiated taking into account a complex array of quality and economic factors. Treatment of third-party concentrates in the South African platinum industry is a comparatively recent development, brought about by the opening up of mineral rights and operations being developed that are smaller than the critical size required to sustain capitalization of smelting or refining plant. Published commercial terms have not been demonstrated to reflect the complexities and subtleties of base metal concentrate markets. This paper outlines some key elements and parameter ranges of base metal concentrate treatment contracts, and applies similar principles to typical Merensky and UG2 platinum group element (PGE) concentrates to determine potential value distribution between the mining and treatment parties in tolling arrangements.

Jan 1, 2012

By Subrata Dutta

Sindesar Khurd Mine is situated in Rajasthan, India, and operated by Hindustan Zinc Ltd, under Vedanta Group. The base metal mine is high in reserves of Lead, Zinc and silver and has been producing since 2007 with initial production of 0.3 mtpa. Recently the mine has gained prominence as a base metal underground mine in introduction of latest mining techniques and achieving high production at lowest costs. The promising Lead-Zinc reserves of Sindesar Khurd Mine (SKM) and high-tech exploration adopted by Hindustan Zinc Ltd (HZL), (Vedanta Group), raising the reserves and resources from a meager 9 Mt (1997) to 81 Mt (2012), has prompted HZL management to ramp up the mine production from 0.3 mtpa (2006-07) to 2 mtpa by 2013-14 with ambitious plans to reach 3.5mtpa subsequently (presently largest underground metal mine in India). The complete trackless system underground mine, recently equipped with latest leaky feeder communication system (unique in India), utilize modern drilling, mucking and hauling equipment aided with various utility/service vehicles. Excavation optimization and quality recovery maximization from the open and post filled stoping methods, continual expert analysis and feedback from International consultants like AMC (Australia) and SRK (UK), and involvement of renowned bodies in management excellence, have lead the mine towards highest productivity and lowest mine operating cost, earning the mine a prominent place in the global base metal industry. The paper deals with how the various challenges in mine planning and designing, mine development, operator skill, equipment introduction and maintenance, expertise availability, provide training and exposure to officials, prompt and effective communication/service, control of ground vibrations, maintain ventilation standards etc are faced in attaining high operational excellence and thus attain a record mine output/man shift (OMS) of 14 ton/man shift with targets to reach 20 ton/man /shift. Scientific designing using 2D/3D numerical mine-modeling techniques, faster stope sequencing with introduction of paste filling ( first time in India),latest leaky feeder communication system, control ground vibration to stringent standards using electronic delay system, faster raising techniques using raise borers to enhance development and ventilation, cavity scanners to monitor large stope voids, fast shaft sinking at 100 m/month(Chinese expertise) and maintaining adequate ventilation with close software monitoring are some of the highlights discussed in the paper towards achieving the targets.

Aug 1, 2013

By AIME AIME

WIDESPREAD interest in the better utilization of coal is indicated by the attendance of over seventeen hundred men interested in the pro- cessing and utilization of coal and its by-products, at Pittsburgh, Nov. 15 to 18. The conference was truly international in scope and of a scientific character, and must be considered a real success. There were dele- gates--official and unofficial-from America, Belgium, Canada, Czechoslovakia, France, Germany, Great Britain, Japan, Mexico, and Sweden. Several Federal and 28 State departments had representatives, also many colleges and universities, and many leading industrial and mining corporations throughout the country. A feature of the sessions was that papers were mostly read in full and attentively listened to, although in some cases they were of a technical nature. The proceedings were opened by the president of Carnegie Institute of Technology, Thomas C. Baker, who spoke of the importance of the conference and felt that without foreign cooperation it could not have been held. There was no need to apologize for the movement of Carnegie Institute of Technology in the matter. Coal is commanding attention in every part of the world; so is power; and coal will remain the chief source of power for generations to come. The coal chemist is working with the engineer, and nobody can forecast what developments there will be in fuel technology. This conference may be the turning point of fuel technology in America. The development and application of these new processes may be of great benefit to Pittsburgh.

Jan 1, 1926

This Bureau of Mines report is a reference manual of procedures used by the Bureau's Twin Cities Mining Research Center for obtaining rock properties. Included in the report are discussions on the usage of each property, descriptions of the general test methods for obtaining the properties, and instructions for performing the tests. The Instructions embrace details of the specimen configuration, test apparatus, test procedure, test conditions, and calculations needed to achieve satisfactory results. Although the procedures presented in this reference manual generally conform to recommendations of the ASTM Administrative Committee on Standards, they are not purported to be standards.

Jan 1, 1974

By N. O. Lotter

The connection between mineralogy and metallurgical performance in a plant was recognised long ago (Gaudin, 1939; Petruk, 1976; Petruk and Hughson, 1977; Cabri, 1981; Petruk and Schnaar, 1981; Kinloch, 1982; Peyerl, 1983, Baum et al 1989 for example). The modern toolbox that we now routinely use for flowsheet development took decades to develop (Lotter et al., 2002; Baum and Lotter, 2004; Lotter, 2011 for example). Many workers contributed considerable time and effort to this overall mission of connecting sampling, mineralogy and mineral processing to integrate the flowsheet development activities. Certain key milestones marked this journey, such as Gy’s treatise on the sampling of particulate materials in 1979, which was later added to by François-Bongarçon, Pitard, Minnitt, and Holmes for example. The development of QEM*SEM by Gottlieb et al. of the MLA by Gu et al. constituted a huge leap forward in accuracy and mineral measurement capacity, as well as a reduction in standard errors of mineral characterisation. The advancement of the microprobe to an automated platform made a significant difference to detailed compositional mineralogy. This led to a strong position from which to draw meaningful processing implications from the mineralogical data. Reproducible flotation testing and reliable plant survey material for characterisation was dealt with by, amongst others, High Confidence Flotation Testing ( Lotter, 1995: Runge, 2010, and Bradshaw, 1997); and Statistical Benchmark Surveying (Lotter, 2005), with earlier prototypes which were steadily improved (Lotter, 1994; Restarick, 1976). The sterling work of Napier-Munn in engaging sound statistical methods with mineral processing led to the successful design and use of methods that could identify and quantify small recovery gains in plant scale trials. This history and present capability are reviewed, including leverage into asset management.

Jan 1, 2018