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By M. Yamine, R. J. Ring, D. J. Waters

"An experimental program has been carried out by the Australian Atomic Energy Commission to compare the effectiveness of Caro's acid as an alternative oxidant to pyrolusite in the leaching of uranium ores from the Alligator Rivers region of northern Australia. Batch leaching tests on Ranger, Nabarlek, Koongarra and Jabiluka ores showed that uranium extraction was unaffected by choice of oxidant, but that Caro's acid reduced acid requirements by 15 - 25%. Lime requirements for neutralization of tailings liquors were reduced by 20 - 30%.The batch studies were extended to a four-stage continuous leaching circuit with a capacity of 400 gore h-I. Comparative leaching tests confirmed the reagent savings obtained in the batch tests. Following these encouraging laboratory results, lnterox Chemicals Pty Ltd carried out plant trials using Caro's acid. Reagent savings in the mill were similar to, or better than, those obtained in laboratory test work. The trials also established that Caro's acid has a number of operational advantages over pyrolusite.IntroductionUranium is most commonly extracted from its ores by leaching in sulphuric acid. Simple hexavalent uranium oxides and compounds are readily soluble but uranium in the tetravalent form is insoluble and must be oxidized for dissolution to occur. The most commonly used oxidants have been sodium chlorate and manganese dioxide. They act indirectly by maintaining iron as the ferric ion which oxidizes uranium by a surface electro- chemical reaction. An Fe3+ concentration of about 1 - 2 g L-I is usually considered adequate for the effective dissolution of uraninite(1)."

Jan 1, 1984

By P. V. Golde, R. A. Poole, G. R. Baiden

"INCO is committed to proceed into the next century using automation and robotics to achieve safety and productivity goals necessary to enhance its competitive position. Stobie Mine, decades old, is the first of its mines to change from labour-intensive to automationassisted techniques. This paper is a synopsis of the progress made during the transition period including overviews of some of the projects as well as some of the difficulties in the assimilation of the technology. BackgroundThe ObjectiveThis paper is an update on remote control and LHD automation installation at Stobie mine. The communications system installed at the mine and the ability to remotely control underground equipment from surface is reviewed (Poole et al., 1996, 1997). It discusses some of the experiences and processes required to further the concept to consolidate the operation of multiple machines under a single operator. It considers the communications systems requirements and their focuses, particularly on the development of systems for the tele-operation of LHDs and drilling machines from surface."

Jan 1, 1998

By D. B. Stewart

In the past few years, much effort has been spent in elucidating the impact of diesel engines on the mine environment. This paper summarizes diesel fundamentals , exhaust emissions and typical tailpipe concentrations. Mine sampling results and an evaluation of exhaust treatment systems are discussed. A review of changes in pollutant concentrations between the tailpipe and the mine exit is made and suggestions are given to reduce operator exposure to diesel contaminants.

Jan 1, 1978

By T. Robson

"A multi-seam underground mining operation employing mechanized room-and-pillar methods provides 35 per cent of Smoky River's annual ROM coal production (2 million tonnes) from the Smoky River coal field. Surface mines provide the balance. Tectonic activity, which has resulted in deformed coal seams and a rugged relief to the area, has provided natural boundaries to discrete mining areas. Coal transportation to the central preparation plant incorporates a 3 km long underground conveying system. The company is committed to efficient resource recovery and a safe and healthy working environment. Introduction The Smoky River Coal operations (SRC) are centered in the Smoky River coal field located in west central Alberta, some 360 km west of Edmonton and 20 km from the Town of Grande Cache (Fig. 1). Combined mining operations produce 2 million tonnes per year run-of-mine coal from which 1.65 million tonnes of high quality, low volatile, coking coal are obtained. The underground mining operation, employing mechanized room-and-pillar methods, provides 35 per cent of SRC's annual ROM coal production (2 million tonnes). Surface mines provide the balance. Tectonic activity has resulted in deformed coal seams and a rugged relief in the area. This has provided natural boundaries to discrete mining areas. Background Exploration of the Smoky River coal field took place over four decades commencing in 1926. McIntyre Mines Limited (parent to Smoky River Coal Ltd.}, commenced development of the property in 1968 having secured a long-term contract for the delivery of coal to Japan. Production of underground coal at Smoky River commenced toward the end of 1969 and has been continuous on the property since that time. Originally, two underground mines were opened. Original planning envisaged the use of room-and-pillar techniques to develop blocks of coal for subsequent extraction by longwall retreat mining. Following initial development, two longwall units were established, the first in November 1970 in No. 5 Mine and the second in February 1971 in No. 2 Mine. Difficulties were experienced on both units, and production commitments could not be achieved. The longwalls were discontinued, and mechanized room-and-pillar was subsequently used for all underground mining."

Jan 1, 1985

By Richard Wells

Peabody Energy is the largest pure-play publicly traded coal company in the world. We have been in business 129 years and like most of the coal mining companies in the United States, since 1969 the majority of our safety improvement efforts had been driven by compliance with the various versions of the Federal Mine Safety and Health Act and the supporting federal regulations. In 2004 Peabody Energy management came to the understanding that in order to achieve our goal of zero incidents, that focus must change. This paper will describe the elements of the journey we began at that point to make the transition to a behavior and systems-based approach to safety management and our efforts to win the minds and hearts of our employees. This journey is undertaken with the goal of making safety truly a way of life for all Peabody Energy employees.

Aug 1, 2013

By Dan Currie, Tom Lamb, J. Coady Marsh, Gary Landry

"This paper describes the Cape Breton Development Corporation's experience with the Lovat M-300 tunnel-boring machine at the Donkin-Morien Mine. Between January 3 and December 21, 1984, the 7.6 m (25 It) diameter TBM advanced 3350 m (10 990 ft) . The authors will describe experiences with the machine and highlight the implications of tunnelling machines to underground coal mine development in Canada. IntroductionThe Cape Breton Development Corporation (CBDC) has recently completed the drivage of a 7.6 m (25 ft) diameter tunnel, 3.5 km (2.2 miles) in length , to access the Harbour Coal Seam at the Donkin-Morien Project. The tunnel was successfully driven with the first Canadian rock tunnel-boring machine (RTBM or TBM), designed and built by Lovat Tunnel Equipment, Inc. The initial mine development consists of the drivage of two tunnels to the first major coal seam. Future plans are proposed for the development of a 4 million tonne-per-year mine (Marsh et al., 1983, Gillman, 1982), which will require the drivage of a further two tunnels and could access up to four coal seams. The tunnel cross-sectional areas were designed to provide sufficient ventilation area and access for a production of 4 million tonnes per year."

Jan 1, 1986

By H. J. White

The effect of alloying elements on the mechanical properties and weldability of wrought gamma prime strengthened nickel- base superalloys is well known. An understanding of the basic guidelines concerning alloying additions has led to the invention and development of HAYNES® 282® alloy for applications in aircraft and land base gas turbines and other high-performance high-temperature environments. The alloy combines exceptional high temperature properties with good weldability and fabricability. At high temperatures (~ 900 °C), the alloy is stronger in creep strength than Waspaloy alloy (UNS N07001) and it approaches the creep strength of R-41 alloy (UNS N07041). Because the alloy has better thermal stability, fabricability, and weldability than Waspaloy and R-41 alloys, it is currently being considered as a candidate universal consumable for welding/ repair welding of gamma prime strengthened nickel based superalloys and it is also being considered as a suitable replacement for applications where R- 41, Waspaloy, and 263 (UNS N07263) alloys are currently being used. The alloy was designed to have improved resistance to strain age cracking, a problem common to gamma prime strengthened nickel based superalloys. In this paper, we present (1) results from hot ductility testing of annealed and annealed/aged material; (2) results from Time Resolved X-ray Diffraction (TRXRD) studies during a welding thermal cycle of annealed and annealed/aged material, and (3) gas metal arc (GMA) and gas tungsten arc (GTA) welding of annealed and annealed/aged material.

Jan 1, 2010

Reaction between xanthate ions in solution and oxidized compounds present on the surface of galena to form lead xanthate is considered to be a side reaction not contributing to flotation, although accounting for some consumption of reagent. The direct reaction of lead sulphide with xanthate and oxygen to form lead xanthate is the most significant to flotation. Coadsorntion of dixanthogen is also involved. Previous work has shown lead recovery in lead rougher flotation to be a function of m [H+] where: m = concentration of xanthate in solution rHl = hydrogen ion concentration. A plausible explanation for this relationship is suggest-ed. Likewise, the experimental findings that the amount of xanthate adsorbed under certain conditions is a function of m'[H+] are explained in terms of reaction between xanthate ions and soluble basic lead salts such as PbO.PbS04? It is also shown that m[H+] should have a constant value in lead cleaners operating at a higher pH than the roughers. This conclusion is confirmed by plant data, and the value of the constant agrees well with the calculated value. The finding is useful in mill control.

Jan 1, 1965

By C. Mawdsley

The Tata Steel mill at Skinningrove in the North East of England produces top hat sections for mineshaft guides in sizes 102 and 150 mm. The top hat section is the technically preferred shaft guide choice for modern deep mine shafts. This paper explores the relative service performance of top hat and square hollow section guides in service. Comparative corrosion performance is reviewed and the paper describes work commissioned by Tata Steel (as Corus) undertaken by Aker Kvaerner Engineering to evaluate relative winding speeds, relative loads and fatigue life in service. The experience of supply to UK Potash mining is discussed and the future view of high capacity hoisting and larger section size market need and availability is assessed.

Aug 1, 2013

By H. R. Huffman

"This paper reviews the history of iron powder production, and outlines the varions production methods. The uses of iron powder and the reasons for its use are also covered. The paper concludes with a look at future trends in powder metallurgy.INTRODUCTION TO POWDERSTHE IRON POWDER INDUSTRY is enjoying a very rapid growth. The annual consumption of iron powder is now at the 100,000-ton level, twenty times higher than it was at the end of World War II, and the yearly in-crease bas been almost consistent at 20 per cent. This is expected to increase, bringing the tonnage to 200,-000, or even (according to some experts) to 270,000, in 1970. In any event, powder metallurgy is expanding at high speed and making an important impact on the production of iron and steel products. Some indication of the faith in the future market may be indicated by the commencement of three new powder production plants in Canada with a total capacity of 136,000 tons annually."

Jan 1, 1969

By Louise Corriveau, Bronwyn Azar, Valerie A. Jackson, Luke Ootes, Jeff Harris

We use the results of new bedrock mapping, combined with geochemical point data and airborne radiometric data (in particular equivalent uranium concentrations) to help determine which geological units in the Paleoproterozoic Great Bear magmatic zone (GBmz) contain elevated uranium. The data collectively indicate that the highest primary uranium concentrations are in equigranular granites and subvolcanic/volcanic porphyries. Notably, these rocks host the majority of known uranium-bearing deposits and/or prospects in the GBmz. We speculate that the uranium in these deposits/prospects was derived from nearby, uranium-enriched rocks and was mobilized by much younger, circulating hydrothermal fluids. Sedimentary rocks of the Thelon and Dismal Lakes groups unconformably overlie the GBmz and are known to host unconformity-type and sandstone-hosted uranium prospects. Most likely, the uraniumenriched rocks of the GBmz acted as a uranium donor to these overlying sedimentary basins. The method of investigation employed in this study may be applicable to other ‘granitic’ terrains in order to identify regions with favourable rocks for uranium exploration.

Jan 1, 2013

By Pingyang Zhang, Caichu Xia, Shuwei Zhou, Yu Zhou, Yongsheng Hu

A lined rock cavern (LRC) is an alternative container for compressed air energy storage (CAES) to store high-pressure air that is later used to produce electricity. A critical requirement of CAES in LRCs is that the inner seal should provide adequate sealing capacity to prevent air leakage from LRCs. In many studies, rubber sheets are applied to build the inner seal. However, air leakage through rubber seals has not been given much attention and rubber seals are usually assumed to be absolutely airtight. Given that rubber is permeable especially under high air pressure, such as in CAES, air therefore leaks through rubber seals during CAES operations. In this study, a numerical analysis was conducted based on the permeation equation of polymers and the governing equations of thermodynamics of CAES caverns to analyze the characteristics of air leakage from CAES caverns through rubber seals. A planned CAES plant in China was considered as a case study. Results show that air leakage rate increases with increasing cavern temperature and pressure during air injection and decreases as cavern temperature and pressure decline during air withdrawal. However, in total, the daily air leakage percentage is in the order of magnitude of 10-3% in a typical operation cycle, which is much smaller than the critical value of 1%. Under a common range of realistic operations conditions, the daily air leakage percentage is still of the order of 10-3%. Therefore, rubber seals can be used to prevent air leakage in LRCs for CAES. However, the experience of Japanese pilot cavern indicates that the specifications for the on-site vulcanization jointing and installation methods of rubber seals still need improvement.

Jan 1, 2015

By M. M. O?Brien

THE SULLIVAN MINE The Sullivan mine of the Consolidated Mining and ? Smelting Company of Canada, Limited, is situated at Kimberley, B.C., nineteen miles from Cranbrook, a divisional point on the Crowsnest Pass branch of the Canadian Pacific railway. Production started on a small scale in 1900, and in 1914 the mine became the largest lead producer in Canada. In 1925 it was the largest single producer of lead and zinc in the world. Since operations commenced, 4,800,000 tons of ore have been produced from stopes and 170,000 tons from development. At the present time, ore is being mined at the rate of 1,100,000 tons per year, with a yield of about 200,000 lb. lead, 110,000 lb. zinc, and 4,000,000 oz. silver. The town of Kimberley is easily accessible by road as well as by rail. The altitude at Mark creek, a tributary of the St. Mary's river, is 3,700 feet. To th'e north of the creek, Sullivan hill rises to a height of 6,100 feet, and it is on the southern slope of this hill that the mine is located. Sullivan hill is in the Purcell range, which rises between the Rocky Mountain trench on the east and Kootenay lake on the west. It thus lies within what is commonly referred to as the East Kootenay district.

Jan 1, 1926

By J. E. Dutrizac, J. B. O'Reilly

"Zinc is a relatively abundant element which occurs as both high-grade sulphide ores {sphalerite ZnS) and oxide ores which the ancients collectively termed ""calamine"" (smithsonite ZnC03 and/ or hemimorphite Zn4Si201(0H)2 - H20 and/ or hydrozincite Zn5(C03) 2(0H)6). Although oxidic zinc is readily reduced by carbon, the process becomes thermodynamically viable only at - 1000°C, and at this temperature the zinc is released as a vapour (B.P. 907°C). Casual cooling of the vapour results in its re-oxidation by excess combustion air or even the carbon monoxide product of the reduction reaction. ZnO + C = C09,, + Zn vapom Only fairly rapid quenching of the zinc vapour and the isolation of the reduction products from the combustion gases will yield metallic zinc; these conditions were not produced deliberately until the advent of distillation technology. Until quite recently, the principal use of zinc was in brass manufacture; galvanized iron was not discovered until the 19th century and zinc casting alloys are a relatively recent invention. As will be seen, brass could be produced without recourse to a pure zinc intermediary, and the discovery of brass preceded that of zinc by many centuries. The purpose of this paper is to outline the discovery and early development of both zinc and brass with special reference to the European scene."

Jan 1, 1999

By F. Fournier Dit Chabert, F. Tancret, J. François Castagné, R. Le Gall

During the repair of turbine blades by a laser cladding process, it is observed that interdendritic cracking occurs in the heat affected zone (HAZ). Auger electron spectroscopy, performed on sample broken at high temperature, reveals interfacial sulfur segregation, which is known to be one of the main causes of microcraking in the HAZ during welding processes. Moreover, thermal gradients generated by the process are responsible for important thermomechanical stresses. In the present work, the finite element code Comsol Multiphysics is used to simulate the laser cladding process in order to determine both the thermal field and, using an elastoplastic law, the stress field inside the component. The originality is that the temperature history calculated in the thermomechanical model is extracted then injected in a segregation model in order to calculate the local segregation behavior. This model can be eventually used to predict the risk of cracking as a function of process parameters and alloy chemistry.

Jan 1, 2006

By G. Stenning

The paper outlines the need for high-volume ventilation in a uranium mining operation based on the design to meet environmental requirements for dust, radiation and diesel equipment. Mining methods in a highly mechanized operation, a key factor in design, are discussed. The construction and installation of major intake and exhaust fans are described briefly, together with the development of the mine airways and distribution system. Controls in the form of doors and bulkheads are important considerations in planning. Finally, the need to lower ventilation requirements in response to increasing power costs will result in future improvements.

Jan 1, 1979

By C. T. Bischoff

Introduction Air conditioning is a term which has come into common use only during our generation. By definition, it means the positive and accurate control of temperature, humidity, movement, purity, and component constituents of the atmosphere within an enclosure. Claiming such results for Noranda's ventilation system, or for that of any other large mine, at present would be an idle boast. However, we are working toward that end with considerable success. Modern underground ventilation at Noranda dates back about six years. The later development of air conditioning is in its fourth season, but still in the experimental stage. Various ingenious methods have been devised to cool mines which, because of climatic or geological conditions or depth, are excessively warm. A few installations have been made to warm intake air during the winter months where this is necessary. However, the method currently in use at Noranda is unique in that it accomplishes both ends by one process. This method utilizes the freezing and melting of ice to equalize year-round temperatures. Mining Methods While a discussion of mining methods at Noranda is not proposed in this paper, a brief summary may be in order. The Horne mine of Noranda Mines, Limited, has been developed by six shafts, four of which are now active. The most recent, an internal shaft, extends to 6,000 feet below surface, but all of the ore mined to date has come from above the 3,000-foot level. Figure 1 shows a model of principal ore bodies. The area mined is relatively small in plan, considering its vertical extent and the tonnage per vertical foot. Most of the ore lies within an ellipse about 600 by 1,000 feet. While this has certain advantages, the mining of such massive orebodies has presented many problems.

Jan 1, 1947

By J. A. L. Henderson

THE potential oil-and gas-bearing area with "which this paper deals is the large undefined Carboniferous basin, roughly triangular in shape, occupying about 10,000 square miles of southern and eastern New Brunswick. Its base, about 135 miles long, lies on the gulf of St. Lawrence and embraces the whole eastern coast-line of the Province, while its apex lies in the south-west corner of the Province, near the International boundary (see map, Figure 1). The Carboniferous basin may be divided roughly into two areas-the Northern basin and the Southern basin-by a structural feature represented by a ridge of low hills running north-easterly from the Saint John river, near Saint John, on the southwest, to Indian mountain, about eight miles north of Moncton, in the northeast. Within the Northern basin, all evidence regarding the presence or attitude of the older Mississippian Albert Shale series, the only oil-bearing rocks known in New Brunswick, is for the greater part obscured by a thick and practically horizontal blanket of Pennsylvanian strata and, although evidences of oil and gas have been reported, none has been positively identified. Five parallellines of gentle folding, running to the northeast, occur in the Pennsylvanian rocks, within a distance of 100 miles from north to south. This folding is reflected in the courses of the rivers, which lie within the synclines. The relationship of the folding in the younger rocks to structures in the uncomfortably underlying older rocks is unknown, but should now be possible of clarification by means of a geophysical survey accompanied by drilling. Independent geological examinations have yielded no evidence of value in this respect, nor have five exploratory boreholes drilled by per-cussion tools to a maximum depth of 3,645 feet been of assistance, as only one inconclusive hole completely traversed the beds which normally overlie the Albert shales.

Jan 1, 1940

By M. Board, R. Pakalnis, S. Seldon, R. Brummer

The Kidd operation mines roughly 10 000 tpd of copper and zinc ore from underground and employs about 700 personnel. In the late summer and fall of 1997, major movements in the proximity of the east wall of the Kidd open pit had been observed. The Kidd pit had been mined from 1965 to 1977 to depths of 260 m (850 ft), followed by subsequent mining by underground methods to current depths in excess of 1830 m (6800 ft). The No. 1 Mine (2600 Level to pit bottom) is approximately 90% extracted, with most of the remaining reserve between 2000 and 2500 levels. Although initial concerns centred on the stability of the pit walls, the potential ramifications of the movements to the underground were recognized and measures were implemented to ensure the safety of personnel as well as to minimize the potential damage to existing operations. In late October, damage to underground operations was observed as deep as the 2000 Level. In the final assessment, the global mobilized mass was a “wedge”-shaped hangingwall block extending from surface to about 610 m (2000 ft) below surface. The “wedge” boundaries are defined by a fault and shear zone which have continuous lengths in excess of 1070 m (3500 ft); its base by shearing through the host rock mass; and its eastern face by deep tension cracks (Fig. 1). Mined and filled excavations at the western face of the “wedge” allowed mobilization of a mass in excess of 30 M tonnes. Movements in excess of 75 cm (30 in.) per day were recorded on the surface stations that preceded the complete shutdown of operations on October 29, 1997. The evaluations in the days following the shut-down were centred on mitigation of immediate and future possible negative impacts on infrastructure and mining of the remaining No. 1 Mine reserves while ensuring the safety of the operators. This effort required the rapid assessment of the potential damage of the block movement on underground infrastructure, stope access, drainage and ventilation, as well as airblast potential due to the falling of a large block into the pit near the ventilation intake at the base of the pit. These assessments were presented in a previous paper (Seldon et al., 1999). In total, the lateral movement of the block on the ground surface was over 4.3 m (14 ft). This paper describes the detailed studies performed to understand the failure mechanism and to assess the impacts on future mining in No. 1 Mine.

Jan 1, 2000

By G. C. Lipsyy

ALL mineral production? of Can11.da is transported in a mine car at some stage during its extraction. There are as many types and varieties of mine cars as there are of mines. Many of the cars in use were developed in the blacksmith shop. Others were designed by engineers and improved by the mine foremen and the mechanics. Every mine car has the ideas of miner, blacksmith, mechanic, and engineer incorporated in it. Many of these ideas are not generally known. This paper was written to make at least some of this information available to the mining industry. In drawings, tables, and notes, it gives all the important details pertaining to the cars. It .does not recommend any particular type of car for any particular piece of work, nor does it present drawings from which a car can be built. It gives the engineer or master mechanic information on many cars which he can apply to his own particular problems. It is hoped that this information will be of use to mine operators. If a few new ideas are conceived as a result of the paper, the author will feel that the effort of compiling it has been worth while. In order to obtain the data for the preparation of the paper, a questionnaire, copy of which is here reproduced, was sent to all the operating mining companies in Canada. An accompanying letter briefly explained the purpose of the paper and asked for co-operation in furnishing as complete information as possible.

Jan 1, 1945