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By L Neindorf

The development and application of paste fill, cement slurry aggregate fill and shotcrete bulkheads at Mount Isa Mines is described. The progressive changes in filling style in the Mount Isa copper mines from a dry fill based cemented rock fill to tailings based paste fill and slurry fills is explained. The development of shotcrete arched bulkheads and engineered drainage system is described. Details on how Mount Isa Mines has achieved approximately 30 per cent cost reduction in backfill operations through innovations are given. The development of a rocky paste fill is explained.

Jan 1, 2005

Great new drilling results! What's so sinful about being a multi-national company? Overseas protestors flown to Australia for a free holiday How to counter the protectionist danger? Our current economic standing Over-regulation puts a convicted paedophile on the payroll The broken window fallacy Mining - A shared history Aristotle and the camels A brighter future? Something over which we do have far greater control, i.e. leadership within our own industry My challenge to you The expanding gold- producing company of which I am proud to be Chairman, Croesus Mining NL, is by definition a æmultinationalÆ. Our shareholders are based in 36 different countries, 77% of our 107 million shares are held in Australia, 23% are held outside Australia, and include New Zealand holdings of 7%. In September, Croesus Mining presented our company at the Mining 2000 Forum in Melbourne, a city caught up with multinational protestors demonstrating against multi-national companies.  

Jan 1, 2000

The area around Big Bell was actively explored and sporadically mined for gold from 1904 onwards. The lease was named Big Bell in 1913. The property became established as a major mining centre with the development of the Big Bell underground mine in 1936. Mining operations commenced in late 1937 and ceased in January 1955, after milling 5.56 million tonnes of ore and producing nearly 21 tonnes of gold. In 1969 Australian Consolidated Minerals Ltd (A.C.M.) acquired the deposit then explored it alone and in joint venture until the current joint venture agreement with a subsidiary of Placer Pacific Limited (PPL) was negotiated in 1984. Following exploration and evaluation of near surface mineralisation, and a reassessment of the remnant pillars underground, the concept of a large open pit in conjunction with an underground mine evolved. The feasibility study was completed in October 1987, and the decision to go ahead was formally announced on 2nd December 1987. Placer Dome Technical Services Ltd were contracted to be the Project Managers, commencing construction on site early in January 1988 and handing the plant over to the operators 13 months later. The capital cost of the project at handover was estimated to be $133 million. The operating team commenced pre-production stripping of the open pit on 1st May 1988. By 31st January 1989 almost 16.0 million tonnes had been stripped and 350,000 tonnes of ore stockpiled.

Jan 1, 1989

A glance at the following chart reveals that because of the continued poor economy, the slump in industrial mineral production continued into 1980. Gypsum was down 17% from 1979; cement down 9%, sand and gravel, 17%, and crushed stone, 11%. All these downward trends reflect the high interest rates and high costs that slowed construction starts. Domestic fluorspar was down 21% and imports off 14% due to the steel iudustry slump. However, potash production was up 8% and phosphate, 5%. Increased drilling activity spurred au increase in barite production of 25%. Most other industrial minerals posted losses with only a few insignificant increases. As expected, prices were higher, reflecting increases due to high costs for labor, supplies, and above all, energy. Increasing energy and transportation costs also had their effect on industrial mineral production. Railroad freight rates increased 16-22% including fuel surcharge; truck rates increased 11-14%a; and ocean freight rates increased 20% for finished goods. The 1979 shortage of boa and hopper cars did not continue into 1980-most likely due to low production of many of the hulk industrial mineral commodities. All in all, 1980 was not a good Year for industrial minerals.

Jan 5, 1981

By A. Anani

The need to optimize surface mining operations has led to the use of discrete event simulation (DES) modeling of truck-shovel systems. Often, these models assume truck cycle times are independent and identically distributed (iid) random variables, although, with significant bunching on the haul routes, this may not be valid. The objective of this paper is to present a methodology to (i) account for truck bunching due to slow trucks; and (ii) test for cycle time dependence (i.e. whether truck cycle time data is iid or not). We built a DES model that accounts for bunching due to a slow truck(s) and used the cycle times as data for further analysis. We then tested for cycle time dependence using Pearson correlation coefficients. The results show significant correlation of truck cycle times for different number slow trucks, with variable speeds. Assuming iid in modeling results in over-estimation of productivity and the uncertainty surrounding it. The over-estimation of uncertainty is pronounced when the relative difference in truck speed increases. The confidence interval of the means of truck loads/shift decreases with increasing number of slow operators. This work extends the usefulness of DES in truck-shovel applications.

Feb 27, 2013

By F. Fraas

ELECTROSTATIC methods are used to separate and concentrate or purify granular particles derived from ores or various synthetic and agricultural products. Compared with other separation methods that require many technological refinements, the electrostatic attraction of fibers, grass, and seeds to charged surfaces clan be accomplished under the most primitive circumstances, and the early development of this method of beneficiation seemed very promising. Precise application of the method to provide high selectivity, however, is a complex procedure, and interest in this method declined. During this period Mr. O. C. Ralston initiated a Bureau of Mines research program oil electrostatic separation. It is the purpose of thins publication to describe the development of the electrostatic method of particle separation from the early beginning to the present resurgence of interest. Most of the information for this description bas been derived from references, a few of which were not available for thorough review. Much information has been drawn from the investitions of the Bureau. Acknowledgments Mr. O. C. Ralston, former Chief metallurgist of the Bureau of Mines, began the research program on the subject and did research on the mils literature. Both Mr. Ralston and Mr. H. B. Johnson, former president of the Huff Electrostatic Separator Co., furnished patent references. A critical review by Mr. F. D. Lamb, Research director, and Mr. M. J. Spendlove, Supervisory metallurgist, Bureau of Mines, College Park Metallurgy Research Center, lifts been of much value in preparing this report.

Jan 1, 1962

By PALMER H. TYLER

WHEN the Mid-Continent Section of the A. I. M. E. met at the roof garden dining room of the Tulsa Club on Monday evening, May 13, most of the members present came prepared with a credulity-stretching yarn of some sort or other, gathered from actual experience. Perhaps it was not realized at the time that such anecdotes would eventually burst into print, but while the excellent dinner was appeasing the inner man the word was passed around that informality and spontaneity of expression would characterize the meeting, with the result that the shackles of convention were eventually cast aside and the meeting waxed better and better until the hour grew ,late, and the chairman, L. G. E. Bignell, originator of the idea, brought to a close what was agreed to be a profitable and entertaining evening. The ball was started rolling by Paul Ruedemann of the program committee, who offered the following:

Jan 1, 1929

(The following-list contains the names of those members of the Institute of whose connection with military service we have only recently. become acquainted.) ADAIR, ARTHUR C., Corporal, 4th Co., 1st Tr. Bn., 154th D. B., Camp Meade, Md. BATCHELOR, STILLMAN, 1st Lieut., Co. 6, E. 0. T. S., Camp Humphreys, Va. BATES, BENNETT R., 1st Lieut., Engineers, Co. 3, E. 0. T. S., Camp Humphreys, Va. BJORGE, GUY N., Co. 3, E. 0. T. S., Camp Humphreys, Va. BOAS, Ross, H., U. S. A. BRADLEY, . H., JR., Capt., 408th Engineers, Camp Cody, N. M. BRINTON, OWEN F., Capt., Engineers, U. S. A. BROWN, HAROLD C., 2d Lieut., A. S. A.P.

Jan 1, 1919

By D. Bienstock

As part of the development of the hot-carbonate scrubbing process by the Bureau of Mines, the corrosion rates of steel in boiling solutions of potassium carbonate saturated with carbon dioxide and hydrogen sulfide were determined, and the effectiveness of various inhibitors was evaluated by Bureau researchers. The highly corrosive solution of carbonate saturated with carbon dioxide can be inhibited with a 0.2-percent concentration of either potassium chromate or sodium metavanadate. Solutions of carbonate saturated with carbon dioxide and hydrogen sulfide are mildly corrosive, 0.01 inch per year. Complete absence of corrosion is obtained with 0.2 percent sodium metavanadate or 0.15 percent vanadium pentoxide. Oxidizing inhibitors such as potassium chromate are destroyed in the alkaline sulfide mixture, N-alkyl trimethylene diamines, at a concentration of 0.1 percent, lower the corrosion rate to about 0.005. Sodium metasilicate, at a concentration of 0.6 percent, completely inhibits the corrosion but may deposit free silica in the system. Commercial cladding materials such as the epoxy coatings also prevent corrosion.

Jan 1, 1962

By B. Stimpson, K. Kosar, K. Barron

"A number of high wall failures have occurred in some of the Alberta coal strip mines of a type called by the authors ""Multiple block plane shear slope failure "". They cause rapid deterioration of the dragline bench, reduced productivity and maintenance costs.The failures are invariably associated with the presence of almost horizontal (± 5 degrees) bentonitic clay bands in the overburden, often immediately above the coal seam, and regress behind the slope as a series of tension cracks which isolate detached blocks. As many as 17 sets of cracks have been observed, at lateral distances in excess of five times the slope height from the toe.The theory of this mode of failure is presented and a limiting equilibrium computer program which will produce deterministic or probabilistic (Monte Carlo) solutions is briefly described. A case history of one such failure is documented. It is shown that the extent of the regressive failure is exceedingly sensitive to the water table elevation, leading to the conclusion that drainage, if practical, represents the best control strategy. IntroductionA number of high wall slope failures are occurring in some of the coal strip mines in Alberta of a type called by the authors ""Multiple block plane shear slope failure""(I). These failures cause a rapid deterioration of the bench from which the dragline operates, reduced productivity, and necessitate conregresses into the slope as a series of tension cracks and detached blocks. As many as 17 prominent cracks or crack zones have been observed, the last being in excess of five times the slope height distant from the toe.The block between each pair of cracks must be at limiting equilibrium, i.e. the factor of safety equals one. This condition can be used to determine the locations of the cracks which develop in sequence behind the face."

Jan 1, 1986

By S. E. James

EAF dust has been listed as a "hazardous waste" due to the presence of lead and cadmium, and at times chromium. The 550,00 tpy production of . .EA]' dust, estimated for the United States alone, contains more than 10,000 tpy of lead and about 250 tpy of cadmium in addition to nearly 1'00,000 tpy zinc. Even though the listing of .EAF dust as a hazardous material stimulated extractive metallurgical work worldwide, process development efforts have focused only on the recycle of the potentially-valuable zinc units. However, the recycle of the lead and cadmium, while not lucrative, is the more critical effort. Horsehead Resource Development Company, Inc. (HRD), in conjunction with its sister company, Zinc Corporation of America (ZCA), has taken a unique approach to total recycle of the toxic heavy metals found in the EAF dust. Impure oxide, produced by either a Waelz kiln or FLAME REACTOR Process and containing the lead and cadmium, is calcined in a rotary kiln at Palmerton, Pennsylvania, to produce a refined zinc-rich intermediate for ZCA's electrothermic zinc plant at Monaca, Pennsylvania. During the calcining operation, lead and cadmium are concentrated in a fume product and shipped to ZCA's electrolytic plant at Bartlesville, Oklahoma. At Bartlesville, a new hydrometallurgical circuit has been constructed and the existing cadmium plant expanded. The combined facilities permit the total recovery of cadmium to refined metal and the lead to .a silver-rich intermediate, which is sold to lead smelters. In this paper the Waelzing, calcining and new leaching facilities will be described.

Jan 1, 1990

CONTENTS PAGE ANDERSON, ARVID E., and CAMERON, FRANK K.-Recovery of Copper by Leaching, Ohio Copper Co. of Utah. Discussed by Thomas B. Brighton, H. C. Goodrich, Arvid E. Anderson, Thos. P. Billings, Frank K. Cameron 2 BEESON, J. J.-Mining Districts and Their Relation to Structural Geology. Discussed by Charles Keyes, Chas. A. Porter 4 DOBBEL, CHAS. A.-Deep-hole Prospecting at the Chief Consolidated Mines. Discussed by G. W. Crane 10 CRANE, G. W.-Notes on the Geology of East Tintic. Discussed by G. W. Crane, H. E. Havernor, N. O. Lawton 11 SACKETT, B. L., BARDWELL, CARLOS, JACOBSON, SIMON, and JENSEN, N. H. Lead Smelting in Utah. Discussed by D. W. Jessup, B. L. Sackett, E. H. Laws 13 BARDWELL, E. S., and MILLER, Roy H.-Pulverized Coal as Fuel for Copper Refining Furnaces. Discussed by L. D. Anderson, E. S. Bardwell, C. P. Crawford 15 WIGTON, G. H.-The Chief Consolidated Volatilization Process and Mill. Discussed by Thomas Varley, S. G. Olmstead, V. O. Lawton, O. C. Ralston.... 16 JESSUP, D. W.-Evolution in the Preparation of Ores for Lead Blast Furnaces. Discussed by W. Spencer Reid, D. W. Jessup, Carlos Bardwell 19 ALLEN, H. P., and MADGE, WM. C.-Chloridizing Mill of the Standard Reduction Co. Discussed by Thomas Varley, H. R. Hanley, H. P. Allen, George H. Dern 20 TUCKER, E. L., and HEAD, R. E.-Effect of Cyanogen Compounds on Floatability of Pure Sulfide Minerals. Discussed by Blarney Stevens 24 Mix, B. E., and BARKER, L. M.-Method of Unloading Ores and Coarse-crushing Practice at Magna Plant of Utah Copper Co. Discussed by W. C. Madge,B. E. Mix 25 KEIGLEY, C. T.-The New Byproduct Coke Plant of the Columbia Steel Corporation. Discussed by W. M. Grant, C. T. Keigley, A. C. Feilder 25 JACKSON, P. W.-Blast Furnace Plant of the Columbia Steel Corporation. Discussed by W. R. Phibbs, H. M. Henton 26 OLDRIGHT, G. L., KEYES, H. E., and WARTMAN, F. S.-Production of Ferric Sulfate and Sulfuric Acid from Roaster Gas. Discussed by G. D. Van Arsdale William E. Greenawalt, G. L. Oldright 27 MAZANY, M. S.-Braden Copper Company Caletones Smelter. Discussed by A. B. Young, G. L. Oldright 36 HARRINGTON, D.-Safety Methods in Utah Coal Mines. Discussed by Edward K. Judd, Otto Herres, Benedict Shubart, A. C. Watts, D. Harrington 36

Jan 12, 1925

In recent years it has been more and more recognised that applied geology can be of service to the mining industry, and many mining companies overseas now have permanent geological staff as part of the operating organisation.Most of these companies insist that the geological department must pay for itself by the savings it can make in operating cost, and the growing use of the geologist is proof that such savings are made.The geological problems in every district are different, and a description of the problems and method of attack in a specified district is a useful addition to the literature of mining geology. Very few contributions, from the standpoint of the mining company geologist, have appeared in the Australian literature so that, although the operations of Bendigo Mines Limited are still in the development stage, and its geological work newly established, a description of the routine geological work at Bendigo should beof interest.Although most Bendigo mining companies have not employed permanent geologists, they have utilised geological guidance wherever possible, and a great body of data has grown up. Acknowledgment is made here to the valuable work of the Geological Survey of Victoria, especially the writings of E. J. Dunn, H. Herman, and H. S. Whitelaw, and the maps of Caleb Thomas and H. S. Whitelaw; and also to the work of independent investigators, notably Chief Geologist, Bendigo Mines Ltd.

Jan 1, 1936

By D. Govender

In recent years, economies of scale have continued to drive copper projects to larger throughputs to offset depleting lower grade resources. A decade ago there were only a small number of projects that stretched beyond 100,000 Mtpd throughput rates. Nowadays and moving forward virtually all the major copper projects are sized beyond this, with throughput rates up to 250,000 Mtpd now under evaluation for a number of key projects in Chile and Peru. This paper explores the development from the 160 m3 flotation cells, through to the 257 m3 cells and nowadays to the 660 m3 machines. The contributions of specific copper concentrators to this growth phase are reviewed herein. The historical basis of flotation machine scale-up is also briefly discussed. Metallurgical results as well as layout, maintenance and operational aspects are highlighted.

Feb 27, 2013

By Y. Nakamura, T. H. Okabe, S. A. Sunkar, K. Nose

Ruthenium (Ru) is known as a platinum group element with a very small production volume. In fact, the worldwide annual production of primary Ru metal is only about 20-30 tons, and it depends on the amount of Pt produced, since Ru is a byproduct from Pt smelting. The primary uses of Ru are as a material for resistors, as a catalyst for electrode materials, and as a sputtering target for hard disk memory storage. In order to recover Ru from the spent sand-blasting abrasive media generated during the cleaning of the apparatus used for Ru sputtering, a hydrometallurgical recovery process using hypochlorite solution has been investigated. In this study, various types of recycling processes that are presently under development are also introduced, and their features and differences are discussed. The advantages and disadvantages of the new recycling processes are evaluated, and the possibility of establishing new recycling processes in the future is discussed from a multilateral perspective.

Jan 1, 2014

By M. N. Shetty

LARGE copper whiskers (-100 p) of 11111 orientation were tested in a floor-model Instron testing machine, at liquid nitrogen temperature. (Testing methods will appear elsewhere.) Whiskers deformed by twinning after some initial deformation. A load-elongation curve at the onset of twinning is reproduced in Fig. 1. Twinning was confirmed by taking a back-reflection Laue picture, using a slit colli-mator, which showed distinct splitting of reflections. The tensile stress reached just before twinning is about 1.4 x 107 g per sq cm (-7.0 x106 g per sq cm—resolved shear stress) which drops to 1.2 x107 g per sq cm (-6 x 106 g per sq cm—resolved). This twinning stress is about five to ten times larger than the value for bulk single crystals of copper deformed at 77°K (-106 g per sq cm—resolved). Twinning models based on Cottrell-Bilby's pole mechanism are discussed in detail by Venables.' In the present work a mechanism based on the idea of failure of a Lomer-Cottrell barrier by recombination will be proposed. An L-C barrier may fail either by recombination or by dissociation.3 Fig. 2 provides the necessary information. It shows that the stress necessary to break such a barrier is about 1.8 x 107 g per sq cm by recombination and 4 x 107 g per sq cm by dissociation at 77°K. The twinning stress reached by whiskers is comparable to the stress level required for failure of an L-C barrier by recombination. (Stroh himself points out that his calculations should not be taken too literally.) We consider a segment of the L-C dislocation which has recombined (AB in Fig. 3) over a length to form the total dislocation which then glides in the

Jan 1, 1965

By Y. Oka, H. Majima

When a rock particle is subjected to an external force, internal stresses and deformations are experienced by the particle. Assuming that the breakage of a rock is mainly due to tensile stresses generated by the action of a pair of concentrated loads, F, directed in compression towards the loading points at the shortest distance, as illustrated in Fig. 1, the stress and deformation experienced by a particle of irregular shape can be determined with the aid of the theory of elasticity. According to the photoelastic experiments made by one of the present authors,' the stress states in a rock particle of irregular shape are quite similar to that of an inscribed sphere of diameter x, as indicated in Fig. 1, but accompanied by the faint stresses, in the vicinity of the particle outside of the inscribed sphere. Therefore, the stress components in an irregularly shaped particle can be estimated by referring to stress components in a sphere. Applying polar spherical coordinates to an elastic spherical body, as shown in Fig. 1, the stress components are all expressed as multiples of F /x2 and more or less influenced by the loading angle and Poisson's number m. In general, the energy w, acting on a rock particle is defined as the product of loading compression F

Jan 1, 1970

By J. K. Gowans

"INTRODUCTIONTo bring a mining property into production in the Canadian High Arctic a company must deal with the harsh environment, the short shipping season and the high cost of labour. In trying to minimize the effect of these factors, the concept of a barge-mounted process plant was investigated as an alternative to the conventionally built concentrator. Cominco's previous experience gained at the Black Angel Mine on Greenland's west coast suggested that this would be a practical alternative.The normal shipping season at Little Cornwallis Island is approximately six weeks long, from mid-August to the end of September. All equipment and materials must be delivered during this small ''shipping window."" The logistics problems are enormous; if the conventional approach had been used the major process equipment would have been delivered to Little Cornwallis Island at the same time as the completed barge actually was! Construction would also be starting at the start of the worst climatic conditions, the Arctic winter. Nine months production was gained by opting for the ""Barge"" approach.What the Arctic winters do to the shipping season, so do they affect the productivity and the cost of labour. Construction labour must come from southern Canada. Thus higher transportation costs and higher wage rates, with more overtime and incentives, increase the labour costs to approximately 50% over normal southern rates. Couple these rates with the lower productivity involved with men working in the extreme cold temperatures and the net effort is worth avoiding. A process plant being constructed in Southern Canada can take advantage of more accessible labour at lower costs, increased productivity and a faster construction schedule. The barge concept must still deliver the equipment and materials during the ""shipping window"" but it can in the completed form."

Jan 1, 1983

The global tunneling industry has many challenges, both technically and financially, with the latter likely to be a significant feature over the next few years. Many industries have ad-opted standard practices in order to overcome specific technical challenges, from which standard out-comes are anticipated. In tunneling, however, every project is unique so standardized practice is not easy. This requires original thinking and being open to adopting new techniques and technologies as they emerge. Sprayed waterproofing is a hot industry topic and a paper recently presented at the North American Tunneling conference not only discussed this methodology for achieving a dry tunnel but also how it can reduce build costs and construction time. Despite their being relatively few ?universal truths? throughout the tunneling industry, there is one opinion that appears to be shared by most in the sector, ?all tunnels leak.?

Jan 1, 2010

In this address I look back over the past 40 years of mineral exploration in New Zealand û essentially the period since the Second World War (ie since 1945). It was the period of my personal involvement, and indeed of the personal involvement of a number of you. Luckily it was aperiod of great interest and activity. In the previous 50 years, virtually nothing had happened, and it is kindest to draw a veil over that period. In the very important earlier 40 years (1855 - 1895) the New Zealand gold rush occurred. That must have been a fascinating, rewarding period, which has been thoroughly documented by better historians than myself. I will simply comment firstly that its mineral explorers (gold-prospectors) were very successful indeed, and found most localities of the minerals they sought, in spite of using very different methods from ours of today. Secondly, they were preceeded by one of Maori exploration, which searched for a much restricted list of minerals, but succeeded in finding virtually every locality we know of today. The explorers of both of these early periods were obviously highly successful, but, in the time available, I must restrict myself to the period since 1945. I am currently editing the effective up-dating of Gordon WilliamsÆ 'Economic Geology of New Zealand' (1974). It covers the last 12 years or so. Many of you are contributing to that volume û both as authors and as referees û and I would like to take this opportunity of thanking you all. Although this new volume excludes the energy field, many of us have been involved in it, and I am therefore including energy minerals in this review, as Williams did in 1974.

Jan 1, 1987