Search Documents

By M. Vallée

"Geological and technical problems are often considered the most important ones affecting new mining projects. Typical problems and likely causes are reviewed based on current Quality Management and Continuous Improvement (QMCI) perspectives, giving particular attention to the work of W.E. Deming. As the “system approach” is an essential part of these policies, its characteristics are described with particular attention given to cultural- behavioural, organizational and systembased constraints described by J. Gharajedaghi. Given that poor communication and interaction among geologists, mineral processors and mining engineers/operators can seriously affect the adequacy of tests, project planning and execution, and mine profitability, these interrelated processes within the mining systems are analyzed and modelled. The impacts on models and simulations of ignoring typical data, information and knowledge uncertainties are addressed. Adapting W.E. Deming’s Fourteen Points, System of Profound Knowledge and insistence on leadership, and the analysis of mining system constraints, will allow the effective QMCI approach required to reduce geological and technical risks. Whenever we achieve this goal, we will be in a better position to overcome environment-, market-, finance- and community-related problems, achieve higher company and industry profitability as well as more sustained development. RÉSUMÉLes problèmes géologiques et techniques sont souvent considérés les plus importants parmi ceux qui affectent les nouveaux projets miniers. Des problèmes typiques et leur causes sont étudiés dans la perspective de gestion de la qualité et d’amélioration continue (GQAC), en relation avec les travaux de W.E. Deming. Comme l’approche système est au centre de ces méthodes, ses caractéristiques sont décrites en donnant une attention particulière aux contraintes de types culturel-comportemental, organisationnel, et systémique décrites par J. Gharajedaghi. Compte-tenu que les lacunes dans les communications et les interactions entre géologues, minéralurgistes, et ingénieurs/opérateurs miniers peuvent affecter sérieusement la validité des essais, de la planification et de l’exécution des projets ainsi que la rentabilité des exploitations, ces processus connexes font l’objet d’analyse et de modélisation. Les impacts sur les modèles et les simulations de l’incertitude des données, informations et connaissances sont soulignés. En adaptant au système minier les Quatorze Obligations et le Système de connaissance approfondie de W.E. Deming ainsi que l’analyse des trois types de contraintes, nous pourrons développer une approche GQAC permettant de réduire les risques géologiques et techniques des projets miniers et des exploitations. Ceci nous pemettra de mieux faire face aux problèmes reliés à l’environnement, aux marchés, au financement et aux conditions sociales, d’améliorer la rentabilité des exploitations minières et de l’industrie, tout en contribuant de façon accrue au développement durable."

Jan 1, 2003

The request for proposal from the U.S. Bureau of Mines outlined the purpose of this study in the following terms. "High grade near surface deposits are largely a matter of history. Most of the current mineral production in the united States is from large low grade ore deposits mined by large scale methods. It appears likely that exhaustion of near surface deposits and public resistance to open pit mining will tend to reverse the present trend toward open pit mining and lead to increased reliance on large scale underground mining. In view of the long lead time needed to improve basic technology, an in-depth study of the major underground mining methods is needed. "This study is intended to provide a systematic review and analysis of large scale non-coal underground mining technology with particular emphasis on current practices and problems, needed technological improvements, existing or potential environmental conflicts, and possible modifications or innovations that will assist in the satisfaction of projected national mineral supply requirements."

Jan 1, 1974

By William H. Tavenner

1. The 1952 Annual Report of the West Virginia Department of Mines lists nine beds that arc being mined in Logan County, of which the Cedar Grove and Chilton are the most important. The Cedar Grove group, No. 2 Gas, and Alma beds have the largest remaining reserves, in the order given. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 short tons per acre-foot of coal in place, are estimated at 5,411 million tons as of January 1, 1954. Of this total, 3,939 million tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics were too meager for making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimate reserves.

Jan 1, 1956

By R. G. B. Pickering

Over the last few years Lonmin Platinum and Sandvik have embarked on a unique partnership of collaboration through a systematic approach to developing equipment to mechanize and automate narrow reef platinum mining. After the initial design and manufacture of the equipment the key aspect is the integrating equipment, people and method into a mining system. Another key aspect of mechanization is the optimization of equipment utilization, and this philosophy has ensured continual evolvement of mining methods. This paper describes the trials and development that have resulted in the mining method described as Lonmin mechanized breast.

Jan 1, 2007

By G. Biles, K. Loughran, R. Anand

The Eskay Creek Mine, a high-grade gold and silver underground mine in northwestern British Columbia started operations in late 1994. For the first three years of operation, ore was crushed to minus 2 inch; blended to satisfy smelter terms and direct shipped to smelters in Japan and Canada. Before commencing the above operations, preliminary evaluations had indicated that an extremely complex metallurgical facility, requiring a large capital investment, would be required to recover the precious and other economic metals. Subsequently markets for raw ore were identified and underground mining and ore transportation operations, at a nominal production rate of 300 tonnes per day, were commenced. Exploration diamond drilling in 1995 and 1996 discovered additional lower grade mineralised zones, which are less economic or uneconomic as direct shipping ore. Test work demonstrated that these lower grade zones could be upgraded to marketable concentrates in a simple flotation mill. The mill was built in 1997 and has been in operation since late 1997. The mining rate now has increased to 400 tonnes per day including 250 tonnes per day of the direct shipping ore and 150tonnes per day of the mill ore. Prime Resources Group Inc. wholly owns the Eskay Creek Mine. Homestake Canada Inc. owns 50.6% of Prime’s shares and manages and operates the mine on Prime’s behalf. This paper discusses the mining and milling operations as well as ore shipment and smelter contracts' administration.

Jan 1, 1999

By Andrew G. Martin

In 1991, Modular Mining Systems began marketing a Slope Monitoring System (SMS) now installed at twelve mines. The SMS uses automated wire line extensometers to monitor field conditions frequently. Every few minutes, the slope displacement values and current temperature are transmitted to a central computer via a packet radio telemetry system. The desktop workstation receiving the data continuously provides updated displays of active slope monitors and generates audible and visual alarms if movement exceeds user specified thresholds. The computer system also generates numerous graphs and reports for quick analysis of slope stability. This work describes the functionality of the SMS, details improvements to the SMS hardware and software developed for several clients, outlines different installation techniques needed for wall rock and spoil monitoring, and interprets slope movement data using illustrations of stable and unstable conditions.

Jan 1, 1996

By Nikolay Boykov

Subsurface imaging technologies are part of the electromagnetic (EM) geophysical methods. EM technologies such as radio imaging method (RIM), ground penetrating radar (GPR), and drill string radar (DSR) have great application potentials in the mining industry. However, the success for applying the EM methods to subsurface observations is largely dependant on the correct evaluation of the electrical properties (i.e., resistivity and dielectric constant) of the rocks in the domain of interest. The depth of penetration of the EM signal in coal, as well as the electrical contrast between coal and subsurface boundary rocks or anomalies, are critical parameters for any successful radar system. Based on the measured electrical properties of the coal seam, the proper operating frequency of the radar system must be chosen in order to successfully detect features such as the coal-roof rock boundary, dykes, and voids ahead of mining. The electrical properties of the rocks in a coal seam are frequency dependent. Even though there has been a great advancement in the hardware and data processing software in the past twenty years, there have not been many examinations of the high-frequency properties of coal measure rocks. In this paper, the laboratory setups, the testing procedure, and case studies will be presented for a wide spectrum of frequencies for coal measure rock samples collected from various US coal fields. Tests have been conducted to study the different conditions, including moisture content, that affect the EM properties.

Jan 1, 2006

By Vijaya Thangavelu

Biological leaching of low-grade nickel laterite is based on a non-traditional leaching of oxide minerals using heterotrophic micro-organisms. The organisms solubilise metals by excreting organic acids; these acids then form complexes with heavy metals. High salinity of water supplies and soils in the vicinity of nickel laterite ore bodies is a major abiotic stress to fungi and represents a major challenge in the application of bioleaching process in-situ. Salinity exposes fungi cells to Na+ toxicity and osmotic stress. This study examined the salt tolerance development of Aspergillus foetidus based on gradual acclimatization of organism, its salt threshold and the salinity effect on its metabolism. The biological leaching of weathered saprolite ore with the resulting halotolerant organism under saline conditions was assessed. It was observed that salinity stress affected the organism?s growth and energy utilization

Jan 1, 2006

By Miklos D. G. Salamon

If all stratifications are horizontal, the computation of surface deformation induced by coal mining involves the prediction of roof and floor convergence and then the transfer of the effects of this relative displacement to the surface through the use of the appropriate influence functions. A laminated model, in the form of a quasi- continuum, provides a simple means of computing the approximate convergence distribution and leads to the Gaussian distribution as the influence function. The ideas presented in this paper represent a subtle but fundamental generalization of the influence function Method. It is postulated that the influence of a small area of extraction is proportional to the roof and floor convergence and not to the thickness extracted. This difference in definition removes many conceptual difficulties associated with the influence function method. To demonstrate the utility of the model, the surface disturbances induced by the extraction of a parallel sided long panel are derived. Formulae giving subsidence, tilt, horizontal displacement and strain are given.

Jan 1, 1989

By John L. White

Vibratory driver/extractors do more than drive and extract sheet piles. I would say more than sixty percent (60%) of the time, vibratory pile driver/extractors are engaged in work that has nothing to do with sheet piles. This is the main reason I refer to this tool as a "driver/extractor", and omit the word "pile". I have spent the last twenty years applying the technology of the vibratory driver/ extractor to all areas of foundation construction. As you will see, the only limits are humankind's ingenuity.

Jan 1, 1997

By F. Charette

The paper reviews recent investigations of the impact of corrosion on the performance of both plain and coated Swellex rock bolts. It addresses the problems associated with estimating and predicting corrosion rates of friction bolts, and based on field data it suggests an empirical relationship to predict corrosion rates. A review of the necessary qualities for a protective coating leads to recent experience with coated Swellex bolts that suggest that they can contribute to extending the useful life of Swellex bolts in potentially corrosive environments.

May 1, 2004

By R. Jolicoeur, J. F. Jackson, M. A. Green

"The design, construction and commissioning of Kiena Gold Mines Limited's new mill was completed in 15 months ending in September 1984. Rated at 1250 tonnes per day the mill incorporates the latest innovative technology such as semi-autogenous grinding, carbon in pulp, pressure stripping and induction furnace refining. The mill is housed in a pre-engineered building with the leach tanks and thickeners located outdoors in spite of the intense winter cold. 1.0 INTRODUCTION AND HISTORYThe operations or Kiena Gold Mines Limited are located in Dubw1sson Township, approximately 10 Km west of Val d'Or, in the Abitibi region northwestern Quebec. Comprised of 59 mining claims covering 1214 hectares, a large portion of the mining property is overlain by the waters of Lac de Montigny. Sometime between 1911 and 1914 Barney Parker discovered gold in a shear zone on an island in Lac de Montigny that now bears his name. The first shaft the Parker Shaft, was sunk in 1936 from the island to a depth of 136 meters but owing to the known veins being of limited extent and the onset of the Second World War operations were terminated in 1940. In the early l960 1 s exploration drilling indicated an orebody of 4,500.000 tonnes at 6.3 grams of gold per tonne. A causeway was built to link the island to the mainland in 1963 and a new 3 compartment shaft was sunk to 403 metres. The orebody was further delineated and the ground conditions within the orebody and surrounds were evaluated.At the end of 1965 the property was placed on a care and maintenance basis as a mining operation would be marginal with gold selling at $35 per ounce."

Jan 1, 1986

By L. H. Banning

This investigation was undertaken to obtain basic information necessary for the design and operation of a plant for recovering metallic values from nickeliferous laterite and serpentine of the Philippine Islands. It was divided into three parts: (1) Mineralogical studies and preliminary mineral dressing tests; (2) electric smelting of the ores, upgrading of ferronickel by blowing with oxygen, smelting laterite slag to produce crude iron, and the production of mild steel; and (3) nickel and cobalt recovery from upgraded ferronickel. Results of the investigation indicate that it should be feasible to recover nickel, iron, and possibly cobalt products from the laterite and ferro-nickel from the serpentine. Mineralogical studies were made on representative fractions of the laterite and serpentine tonnage samples and on five selected samples; mineral dressing tests were made only on laterite. The nickel occurs principally associated with hydrous iron oxides and chemically combined with serpentine; garnierite was the only discrete nickel mineral identified, and it was found in a highly decomposed serpentine. The bulk of the cobalt was found in wadlike manganese oxide material. Approximately twice as much chromite was found in the laterite as in the serpentine, By mineral dressing techniques, laterite was separated into two fractions: one fraction contained over 90 percent of the nickel and cobalt, and 83 percent of the iron; the other fraction contained 74 percent of the chromium. A cobalt concentrate (1.1 percent Co) was produced by a scrubbing and sizing procedure.

Jan 1, 1962

By N N/A

To the members of The South African Institute of Mining and Metallurgy We have audited the annual financial statements set out on pages 239 to 245. These financial statements are the responsibility of the Institute?s Council. Our responsibility is to express an opinion on these financial statements based on our audit. Scope We have conducted our audit in accordance with statements of South African Auditing Standards. These standards require that we plan and perform the audit to obtain reasonable assurance that the financial statements are free of material misstatement. An audit includes: ?examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements ?assessing the accounting principles used and significant estimates made by management ?evaluating the overall financial statement presentation. We believe that our audit provides a reasonable basis for our opinion. Audit opinion In our opinion, the financial statements fairly present, in all material respects, the financial position of the Institute at 30 June, 2000, and the results of its operations and cash flows for the year then ended in accordance with South African Statements of Generally Accepted Accounting Practice.

Jan 1, 2000

By E Breese

The Grey River dredge is the first large scale alluvial operation to be permitted under the Mining Act 1971 and the Water and Soil Conservation Act 1967. The experience of Grey River Gold MiningLimited in pursuing these statutory approvals has identified weaknesses and strengths in the present system and problems which need to be resolved. The Company has learnt lessons, which if heeded, will assist future large scale alluvial mining projects.

Jan 1, 1989

By S. V. Burr

"A 28-year study of cross folds leads to the conclusion that the northwest-southeast folds recognized in many areas of North America are part of a regional pattern. Detailed examination of over 650 geological maps and reports of Ontario indicates that this folding can be traced across the province. Evidence is presented that this fold pattern played an important part in determining the pattern and scale of intrusion, that its recognition in the field can aid in defining stratigraphy, folding and faulting, and that it may have played an important role in channeling hydrothermal or magmatic mineralization. IntroductionThe concept of regional cross folding in Ontario is not new. W.H. Gross (1955) discussed regional cross folds in the Archean of Northwestern Ontario, and A.M. Goodwin (1961) referred to regional cross folds in the Archean of Ontario and Quebec. However, the interpretation in this paper is new.The writer saw a cross fold for the first time, underground, at Little Long Lac Gold Mines in Geraldton, Ontario, in 1951. This recalled the ""transverse folds"" on E.R. Faribault's classical maps of Nova Scotia, published by the Geological Survey around the turn of the century; M.E. Hurst's cross fold(s) at Timmins, Ontario (Figure I); and the cross folds mapped by A.W. Jolliffe in the Yellowknife area of the Northwest Territories. All these mapped cross folds had one thing in common with the fold at Little Long Lac: A northwest-southeast axial trend. Were such cross folds of purely local extent, or might they be indicative of a widespread regional fold pattern? If so, has such folding any significance for mineral exploration or potential?By 1959, based on a study of about 1000 Canadian geological maps and reports, including 291 in Ontario, the writer reached the conclusion that cross folding trending northwest-southeast is so widespread as to constitute a pattern of folding, and that such cross folding should produce changes in plunge along pre-existing greenstone fold belts."

Jan 1, 1980

By V Poizat

In different parts of the world the term epithermal is commonly used for a variety of deposit styles. Using the redox state of the ore-forming fluid (inferred from mineralogy and alteration), the metal assemblage of deposits, and other characteristics, at least five different styles of epithermal deposit can be distinguished. Most of these different deposit styles appear to be related to magmatic fluids, with differences resulting from different compositions of source magmas. The most common style of epithermal deposit (low-sulfidation gold-silver deposits associated with calc-alkaline volcanic rocks) remains the most difficult to explain; the metals in these deposits may be derived by basement leaching without magmatic input, or they may come from magmatic volatiles, with contaminated I-type or S-type magmas as the most likely source.

Jan 1, 1995

By J. Richter, D. Schulze

J. Richter and D. Schulze (Deutschen Akademie der Wissenschafte zu Berlin)—Introduction. In a recent paper R. G. Garlick and H. B. Probst reported on experimental results of investigations of room-temperature slip in zone-melted tungsten single crystals.17 In the paper it was pointed out that slip lines could be detected with an optical microscope only after about 10 pet plastic strain of the crystal. In our investigations we could observe slip lines in tungsten single crystals of defined orientations already with an elongation of 0.02 to 0.03 pet.18"9 Experimental Technique and Results. The tungsten single crystals were produced from 4 to 5 mm sintered rods* as starting material by electron- beam zone melting. With single-zone-pass melting a speed of 0.5 mm per min was used, while three-pass melting could be handled at a speed of 3 mm per min. Crystal axis orientations were located in the shaded area of the stereographic triangle, see Fig. 6. Orientation 1 is located at about 18 deg and orientation 2 at about 5 deg on the great circle from [011] to [ill]. This corresponds approximately to the orientations P and M referred to by Garlick and Probst. Our single crystals had a length of about 70 mm and were profiled solely by electrolytic means, leaving grip ends at both ends of the crystals. Between the latter, a cylindrical crystal of 45 to 50 mm length and about 2.4 mm diam was obtained. The crystals were deformed at room temperature in a commercial tensile-testing machine to obtain a strain of 0.02 to 5 pet. The average strain rate e = eP/t for all tensile tests amounted to approximately 10 -6 to 10-5 per sec, with ep representing plastic strain and t the duration of applied stress. In Fig. 7 a crystal is shown elongated by 0.03 pet. The picture was obtained by means of an optical microscope. Figs. 8 and 9 give electron-microscopic pictures of slip lines of crystals elongated by 0.07 and 1.1 pet, respectively. For crystals with the orientation 1, see Fig. 6, only the two main slip systems (101)[111] and (110)[111] were found. With the crystals of group 2 the two main slip systems are again evident, with

Jan 1, 1965

By Don W. Lake

Of all the blast monitor& instrumentation systems and techniques av&able today, highspeed photography and videography remain as the most valuable, stand alone, diagnostic techniques to evaluate full scale blasts in the mining and explosives industries. Highspeed image data, coupled with information from other instrumentation systems, such as continuous VOD records, seismographs, laser surveying systems, refraction seismographs, etc. can eIiminate many assumptions about what actually took place in a blast. Thus, diagnostic confidence in evaluating both good and bad blasts is increased, and optimum blast designs are achieved considerably faster when compared to the trial and error approach or relying on just the experience factor.

Jan 1, 1992

Size Separation Pretreatment and Alumina Recovery from Bayer Red Mud

Sep 13, 2010