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By M. F. Lopez, A. J. Mattus, S. B. Magid, D. B. Mobbs

"The use of Caro's acid as a replacement for hydrogen peroxide for the oxidation of vanadium prior to solvent extraction resulted in a 56% reduction in oxidant usage when compared on an equivalent hydrogen peroxide basis. Comparative oxidation tests, using two actual uranium mill raffinates, resulted in premature precipitation of an amorphous ferric vanadate when hydrogen peroxide was used to oxidize one of the raffinates containing a high iron to vanadium ratio. The use of Caro's acid eliminated the precipitation problem, thereby permitting the adjustment of the raffinate pH to a higher, more favourable level prior to solvent extraction.Potentiometric characterization of the raffinates revealed that vanadium is responsible for the inefficiency of hydrogen peroxide compared with Caro's acid, with the oxidation efficiency of iron being the same for both oxidants. A limiting potential between 720 and 740 mV was observed when using hydrogen peroxide, while, when using Care's acid, potentials approaching 1200 mV were achievable.A four-stage, countercurrent extraction performed on the oxidized raffinates did not reveal any operational problems. The extraction efficiency and the extraction coefficient were found to be higher when Caro's acid was used as the oxidant, as opposed to hydrogen peroxide.IntroductionMost vanadium is recovered as a by-product of some other process: leaching of Carnotite uranium ores, oil fly ash, phosphate rock or chromite processing. The major source of vanadium has been from uranium mills incorporating acid leaching of Carnotite ore s at elevated temperatures and pressures. The by-product recovery of vanadium from uranium ores of the Uravan Mineral Belt, located in the Colorado Plateau , is a common occurrence when vanadium recovery is economically viable."

Jan 1, 1983

By A. Mosqueda Martinez, L. C. Trytten, R. P. Kofluk, J. J. Budac

The Corefco ammonia leach nickel refinery treats Ni-Co mixed sulphides from the high-pressure acid leaching of Moa Bay nickel laterite. Due to the low iron content of the feed, the ammonia leach process generates a leach residue with ~10% Ni+Co. Since commissioning a leach residue pressure filtration circuit in 2002, this residue has been stockpiled, dried, and sold commercially. For several years, the residue was sold to nickel smelters overseas. In 2014, re-processing of the residue in the high-pressure acid leach was tested. Lab test work was completed showing excellent extraction of the contained nickel and cobalt, and additional beneficial effects in the high-pressure acid leach circuit. A plant test in Moa confirmed the results, and preparation for shipment of the valuable leach residue for re-processing has begun. This paper outlines the test work and results, and some commercial considerations.

Jan 1, 2015

By S. H. Ash

No single factor in modern civilization has played a more important part in the lives of our people than mechanization in industry and to it civilization owes much of its progress. In no industry has mechanization met more opposition than in coal mining, where ?the introduction of mechanical equipment has been opposed on many fronts for economic and social reasons. The term 'mechanization? as used in this report refers to the application of machinery to cutting, loading, and transporting coal from the face to the mine cars. During 1933, 84.7 per cent of the underground production of the bitu-minous-coal mines of the United States (1) was cut by machines, while in Washington only 17.6 per cent was machine-cut. Information in this report has been obtained from personal observations and from operating officials in the Roslyn-Cle Elum coal fields, especially D. R. Swem, manager of coal operations, and Thomas Murphy, superintendent, of the Northwestern Improvement Company, to whom the author is indebted for assistance. INTRODUCTION Although Washington coal-mining problems relating co mining methods, ventilation, drainage, and preparation of coal have been discussed in many publications, little has been published on mechanization in this region, principally because it has not been accepted generally that mining machines, mechanical loaders, and conveyors are necessary or economically adaptable to the variable and steeply inclined coal beds of Washington. Production of coal in Washington reached its maximum in 1918, when 4,128,424 short tons were produced; from that year, the trend was downward until 1934, when production was 1,383,103 short tons, the lowest since 1898; for the past two years, production has risen steadily.

Jan 1, 1937

By F. C. Grensing, W. R. Crib

Copper-15 Nickel-8 Tin alloy is a relatively modern material, having been discovered in the 1970’s. It has complexities with casting, hot working and interdependent solid state phase transformations. A key to the high reliability manufacture of wrought rods, bars, plates and tube is the casting technology, which limits segregation, promotes microstructural uniformity and enables hot working. The EquaCast® continuous casting process has enabled the production of a broadening variety of wrought forms with typical yield strengths ranging from 100 to 180 ksi (690 to 1241 MPa) depending on size, shape and temper. This paper reviews the characteristics of wrought Copper-15 Nickel-8 Tin products which have registration in AMS specifications (4596 and 4597) and MMPDS-04 (CN-1) for use in aircraft. The design limits, microstructures, fracture characteristics and tribological behavior will be examined. This alloy system is emerging as a material of choice for aircraft bearings, corrosion resistant oil and gas exploration components, machinery and demanding off-road equipment applications. ToughMet® 3 is an alternative or upgrade to conventional moderate and high strength aluminum bronze bearing alloys.

Jan 1, 2010

By W. L. Hunter

The preparation of coal for the commercial market is a study both varied and wide, and can be viewed from many angles and in different ways. This short paper can but touch upon the subject and is intended to discuss briefly preparation plants which in some cases would seem to be quite inadequate. The conditions confronting most operators are similar, inasmuch as the existing plants were not built specifically to prepare a product for the market of today, but rather of yesterday. The tremendous strides made in the field of combustion in recent years require that the product be of the highest grade procurable, and in a glutted and somewhat restricted market the buyer may be more pernickety than otherwise. These would appear to be the conditions of today. Where a mine is operated individually, better all-round results seem more readily procurable than in a consolidated effort where so many different conditions are sure to arise demanding cognizance, and in many cases requiring to be incorporated in the scheme of things. In the case of a number of mines being administered to form a central source, that source not having had anything to do with the bringing into being of the institutions over which it presides, we find some of the mines well equipped with facilities to properly screen and load the coal, while in others the facilities are not so good, but are doing their share towards delivering a product that will pass muster and in such quantities that they can be counted on.

Jan 1, 1930

By J. J. Jonas, G. R. Stewart, N. Pokutylowicz, S. Yue, R. Varano, A. Elwazri

Differing thermal histories in and around a weld can lead to differences in grain size, phase composition and morphology of precipitates; mechanical properties will vary accordingly. Hardness testing gives limited information and the machining and testing of tensile and/or impact specimens that would reveal these variations (which may occur over very small distances) is not practical. Therefore, in this investigation, shear punch testing was applied to measure the variation in the room temperature mechanical properties of a welded pipeline steel.

Jan 1, 2005

"In 2000 the CIM Council approved the CIM Standards on Mineral Resources and Reserves – Definitions and Guidelines, developed by the CIM Standing Committee on Reserve Definitions. The Definition Standards established definitions and guidelines for the reporting of exploration information, mineral resources and mineral reserves in Canada. The Mineral Resource and Mineral Reserve definitions are incorporated, by reference, in National Instrument 43-101, Standards of Disclosure for Mineral Projects, which came into force in Canada in February 2001 and was amended in December 2005.CIM DEFINITION STANDARDS- For Mineral Resources and Mineral ReservesPrepared by the CIM Standing Committee on Reserve DefinitionsAdopted by CIM Council on December 11, 2005FOREWORDCIM Council, on August 20, 2000, approved the ""CIM Standards on Mineral Resources andReserves - Definitions and Guidelines,"" developed by the CIM Standing Committee on ReserveDefinitions. The CIM Definition Standards on Mineral Resources and Reserves (CIM DefinitionStandards) establish definitions and guidelines for the reporting of exploration information,mineral resources and mineral reserves in Canada. The Mineral Resource and Mineral Reservedefinitions were incorporated, by reference, in National Instrument 43-101 - Standards ofDisclosure for Mineral Projects (NI 43-101), which became effective February 1, 2001.At the August 20, 2000 Council meeting a new CIM Standing Committee on ReserveDefinitions was established consisting of the following: John Postle, Bernie Haystead, LarryCochrane, Normand Champigny, Mike Hoffman, Colin McKenny, Jack Mullins, Phil Olson,Fred Payne, Jody Todd and Joe Ringwald.Subsequent to the publishing of the August 20, 2000 CIM Standards on Mineral Resourcesand Reserves, various CIM committees have compiled and published more extensivedocumentation on mining industry standard practices for estimating Mineral Resources andMineral Reserves. These standard practices provide more detailed guidance than that containedin the August 20, 2000 CIM Standards on Mineral Resources and Reserves. On November 14,2004 CIM Council adopted an update to the CIM Definition Standards to reflect the moredetailed guidance available and effect certain editorial changes required to maintain consistencywith current regulations. This version of the CIM Definition Standards includes further editorialchanges required to maintain compatibility with the new version of National Instrument 43-101which is expected to become law at the end of 2005. The CIM Definition Standards can beviewed on the CIM website at www.cim.org."

Jan 1, 2003

By Sune Eriksson, Stig Peterssonsune, Christer Fridfeldt

"Boliden Metal Corporation has developed a technique to treat complex copper concentrates containing large amounts of lead, zinc, arsenic, antimony and bismuth which cannot be treated in conventional smelters due to the impurities.Tests were carried out to treat such complex copper concentrates in the TBRC. They were performed in a pilot-plant TBRC with charges of 5 tons. These tests resulted in a new method to treat complex copper raw materials and produce a blister copper low in impurities. The background and data from the test work are presented as well as a flowsheet for a full-scale process.IntroductionThe Ronnskar Works is situated on the coast of the Gulf of Bothnia, 40 miles east of the Boliden Mine. Smelting began at Ronnskar in 1930 to process the complex ore extracted from the Boliden Mine. The Ronnskar Works has subsequently developed into a relatively integrated smelting plant.Copper and lead sulphide concentrates from Boliden's own mines as well as purchased copper raw materials are processed. The main products are refined copper and lead, but full utilization of the raw material also yields other metals and some metallurgical and chemical by-products. The products include gold, silver, zinc clinker, white arsenic, arsenic salts and arsenic metal , selenium and selenium compounds, nickel sulphates, sulphuric acid and liquid sulphur dioxide."

Jan 1, 1981

By A. S. Bayne

THIS paper will present a review of the mining operations of one of Canada's most lately established gold mining districts (1). The history of the Little Long Lac and Sturgeon River areas is interesting in view of the fact that, although they have long been the scene of a certain amount of mining activity, they remained little more than an uninhabited wilderness until 1933, since which time ten producing gold mines and mills have been established in permanent operation, eight of these having entered production since the beginning of 1937. As complete a background as possible will be given concerning the major influences having a bearing upon living and economic conditions in the mining communities. The object, here, is to show the diversity of problems which demand the attention of the operator starting up and operating a new mine in present times, and to indicate the ways in which these problems are successfully met in this district. A description of the power facilities and plant equipment will be followed by a summary of the problems encountered and methods applied in exploration and development. This is to aid in forming a background showing the circumstances which influence the mining methods and costs of the various operations. The paper will conclude with a description of the mining methods used and the costs of the operations, including summarized analyses of the stoping methods and mining conditions. The various phases of operation will be dealt with separately, in so far as this is possible, in order to present clearly the salient features. It is necessary, however, that the reader bear completely and constantly in mind the fact that in actual operations these phases arc, to a large extent, intimately related and greatly affect each other, as well as being, in turn, affected by other circumstances beyond the control of the operator. A few of these circumstances are: capital available during the development period and early stages of productive operation; strength of rock comprising the ore and its boundary walls; grade, size, shape, and location of ore-bodies; and many other natural items which must be carefully weighed in relation to the details of operation.

Jan 1, 1940

By L. R. Plitt

A series of experiments were carried out in an effort to develop a universally applicable mathematical model of the hydrocyclone classifier. The design and operating variables studied were: cyclone diameter and height, the inlet, vortex finder and apex diameters, the feed pressure and the solids content of the feed slurry. The model consists of four basic equations which express the cut size ( dso), volumetric split between overflow and underflow, volumetric throughput, and sharpness of separation in terms of the operating and design variables. Although empirical, the model is nevertheless in general agreement with fundamentally derived models. The model clearly 1•eveals the effect of the major variables on the operation of a hydrocyclone. Because of its broad data base and the inclusion of all the major variables, the model may be used without experimental data to predict the operation of cyclones over a wide range of different operating conditions. With operating data, the equations may be modified to serve as an operational model.

Jan 1, 1976

By Dale A. Sketchley

The objective of Quality Assurance and Quality Control programs on advanced exploration projects is to ensure that data from sampling, assaying, and recording of geological observations are of high integrity for the purpose of obtaining reliable mineral resource and reserve estimates. National Instrument 43-101 Standards of Disclosure for Mineral Projects states that all scientific and technical reports must be prepared and certified by a Qualified Person in accordance with professional and industry standards following Mineral Exploration Best Practices Guidelines and Definitions, and Guidelines of the CIM Standards on Mineral Resources and Reserves. Additional information is given in Companion Policy 43-101CP and Technical Report Form 43-101F1. Although the Qualified Person must discuss and describe the Sampling Method and Approach; Sample Preparation, Analyses, and Security; and Data Verification; there is little specific information in the guidelines on Quality Assurance and Quality Control programs. Examples from the Oyu Tolgoi Cu-Au Project are given for optimizing sampling protocols, following proper sample preparation procedures, safeguarding sample shipments through chain of custody, ensuring quality of assaying with Round Robin monitoring programs, verifying transcribed data, and validating data with check assays to ensure high integrity for resource and reserve estimation. Oyu Tolgoi, also known as Turquoise Hill, is in the South Gobi desert, Mongolia, about 550 km south of the capital city of Ulaanbaatar, and 875 km northwest of Beijing, China. The project covers a major copper-gold system, which consists of the South West, South, Central, and Far North deposits, comprising high sulphidation and porphyry mineralization with oxide, supergene, and hypogene ore types. Exploration is done by multiple diamond drill rigs, and samples are prepared on-site and shipped to laboratories in Mongolia, Canada, and Australia for further preparation and analysis.

May 1, 2003

Surfaces forces have been measured between gold sphere and gold-coated glass plate in xanthate solutions using an atomic force microscope (AFM). The measurements conducted in potassium amyl xanthate (PAX) and potassium ethyl xanthate (KEX) solutions showed long-range hydrophobic forces, with the force curves showing no evidence for nanonubbles on the surface. The strongest hydrophobic force was measured at contact angle of 94° with a decay length of 23 nm. The hydrophobic force became weaker at higher concentrations and after a long immersion time, which may be attributed to the xanthate species adsorbed on top of the first mono layer. The hydrophobic force became stronger when the residual xanthate solution is displaced by pure water, indicating that hydrophobic force becomes the strongest in pure water.

Jan 1, 2009

By Y. Guglielmi, C. Gout, P. Henry, P. Dick, C. Nussbaum

For a decade, observations and experiments conducted in underground environments worldwide (mines, underground research laboratories - URL) made it possible to bridge the scale gap between laboratory scale and large scale faults. Indeed, underground rock laboratories allow developing decameter scale relatively well constrained experiments at the smallest distance from the hypocenters. URL’s experiments allowed developing new monitoring technologies coupling pressure-strain-seismic measurements and reproducing complete earthquakes sequences analogous to natural ones. They also allowed exploring past movements of faults and sometimes also paleofluids in three dimensions and characterizing different fault architectures and hydromechanical properties in unaltered conditions. This is particularly important in the study of faults affecting clay formations which could not be observed at the Earth’s surface because of the high alteration. Here we show how examples from the Mont Terri (Switzerland) and Tournemire (France) The URLs may help in (i) defining the concepts of fault architecture in shales, (ii) estimating fault hydromechanical properties from field decameter scale experiments. Some key results are that faults which are critically stressed or at the rupture limit can reactivate for stresses variations within the range of those produced by shallow underground excavations, and that slight micrometer-to-millimeter scale reactivations may lead to large factor-of-10-to-1000 permeability increases. Such promising results show that URL’s experiments may bring new insights on some key processes that control the relations between fault stability and permeability evolutions in very permeable layers.

Jan 1, 2015

By F. C. Robles Hernandez

This paper presents the results of the electromagnetic semi-solid treatment of the 319 aluminum foundry alloy, Various levels of structure modification were achieved controlling the AC current used to create the Electromagnetic Field, thus manipulating the intensity of the field, The level of grain refinement, partial modification of the Al-Si eutectic, as well as cellular dendrites were observed, A quantitative analysis of the structure was performed using Image Analysis (IA) techniques. In addition a novel Thermal Analysis methodology was developed for the on-line determination of the microstructure modification level.

Jan 1, 2004

By J. R. Emery, D. F. Coates

"FOUR PAPERS ON CEMENTED BACKFILL were given at the Annual General Meeting of The Canadian Institute of Mining and Metallurgy in 1970:Weaver, W. S., and Luka, R., ""Laboratory Studies of Cement-Stabilized Mine Tailings"".Pasieka, A. R., Beattie, H. F., and Espley, G. H., ""Cemented Hydraulic Backill within the Falconbridge Group of Companies"".McLeod, P. C., and Schwartz, A., ""Consolidated Fill at Noranda Mines Limited (Geco Division)"".Clement, W. P., and Sokoloski, R., ""Pumping Cemented Backfill"".These four papers give the impression of a development in mining technology that has been substantially completed. Somewhat over ten years ago, The Inter-national Nickel Company of Canada, Limited and Falconbridge Nickel Mines Limited started experimenting with the addition of Portland cement to mill tailings to produce improved backfill and cheaper floors for scraping. Shortly after, the Canada Cement Company Limited (now Canada Cement Lafarge Ltd.), with full support of the two mining companies, started an extensive research program to provide the technologic-al data necessary to exploit what was obviously going to be a significant development in mining technology."

Jan 1, 1970

By Michel Jébrak, Claude Bellehumeur

Abstract - Regional and orientation geochemical stream sediment surveys were carried out by the Quebec Department of Energy and Resources in southwestern Quebec, over a part of the Mont­ Laurier Terrane of the Grenville Province. The area contains some small stratiform zinc deposits. The response of Zn mineralization to geochemical surveys is weak; the known mineralization is not defined by anomalous samples and consistent patterns. This study uses a technique that increases the geochemical signature of Zn mineralization in filtering out geochemical background components related to lithologies and surficial conditions. The background variations were modelled using principal component analysis, and the filtering technique consists of the partial reconstruction of the data matrix from results of principal component analysis . The filtering procedure considerably enhances the Zn anomalies located in the catchment basins of Zn deposits, and defines some new anomalies in proximity to the marbles of the Mont-Laurier Terrane, the principal metallotect of Zn mineralization.

Jan 1, 1993

By W. E. Davies

"This paper is the sequel to that on Developments in Sintering Efficiency delivered by Davies and Mitchell at the International Ore Dressing Congress, Stockholm, 1957. Attention is drawn to the fundamental concept of sintering as a heat transfer process, in which the ignition heat is continually transferred onward through the bed as a heat wave. By its passage, this heat initiates endothermic 'changes, such as carbonate decomposition, whose energy requirements are supplied by the combustion of the fuel contained in the bed.Ideally, the heat wave should be generated by the ignition hood followed by the pre-heating of the incoming air. The fuel content of the bed should be no more than the theoretical quantity needed to balance the endothermic changes. In practice, the heat wave is seriously short of energy and this is offset by excess fuel in the bed. As a result, sinter quality suffers, more return .fines are produced, and fuel is wasted, a loss of efficiency which could be avoided if the fundamentals of correct ignition were more widely appreciated.Sintering speed, otherwise heat wave velocity, is a function of the rate at which the incoming air acquires .heat from the cooling sinter and imparts it to the unburned feed below the combustion zone. It is thus a function of rate of air flow and so depends on bed permeability>. Ways of• improving and maintaining permeability at the maximum consistent with thorough sintering are discussed, particular reference being made to taconite concentrates. The possibilities of recrystallizing refractory ores into forms more amenable to physical concentration techniques by sintering are visualised, very little expenditure on heat energy being required when the process is operated near the ideal conditions."

Jan 1, 1960

The importance of understanding the behaviour of cemented paste backfill (CPB) within the framework of the effective stress concept is highlighted in this paper. Only through an understanding built on this concept can problems such as barricade loads, the rate of consolidation and arching, be fully understood. The critical importance of the development of stiffness during the hydration process, and its impact on factors such as barricade loads, is used to illustrate why conventional approaches that implicitly ignore the effective stress principle are incapable of capturing the essential components of CPB behaviour.

May 1, 2007

By M. King Hubbert

"The present large-scale use of energy and power by the human species represents a unique event in the billions of years of geologic history. Furthermore, in magnitude, most of the development has occurred during the present century. In the United States, the peak in the rate of petroleum production occurred in 1970 and that for natural gas is imminent. The peak in the world production of crude oil is expected to occur at about the year 2000 and that for coal production at about 2150 or 2200. For other sources of energy and power, water power, geothermal power and tidal power are inadequate to replace power from fossil fuels. Nuclear power, based on the breeder reactor and utilizing lowgrade deposits of uranium and thorium, has a larger potential than the fossil fuels, but it also constitutes a large perpetual hazard. The largest source of energy available to the earth is solar radiation. This source has a life-expectancy of a geologic time scale, is nonpolluting and is larger in magnitude than any likely requirements by the human s pecies. In consequence of the large supplies of available energy, the period since 1800 has been one of an unprecedented exponential industrial growth. This also has been accompanied by a world-wide ecological disturbance, including that of the human population. It can easily be seen that such a period of growth must be ephemeral in character and, in fact, is now almost over. One aspect of this transition from a state of exponential growth to a state of nongrowth is the present alarm over an ""energy crisis."" Actually, the world's present problems are by no means unmanageable in terms of present biological and technological knowledge. The real crisis confronting us is, therefore, not an energy crisis but a cultural crisis. During the last two centuries, we have evalved what amounts to an exponential- growth culture, with institutions based on the premise of an indefinite continuation of exponential growth. One of the principal consequences of the cessation of exponential growth will be an inevitable revision of some of the tenets of that culture."

Jan 1, 1973

By John Vergunst

"This paper traces the development of Ontario 's cap lamp standard. Over the years, numerous Coroner's Juries investigating fatal mine accidents have made recommendations with respect to underground lighting. As well, recommendations to improve mine lighting have been made by two Commissions, investigating mine safety in Ontario.During the past few years, the performance of any cap lamp worn by miners involved in serious accidents, have been measured by the Mining Heal/h and Safety Branch. Large variations in light output were found between and among cap lamp types. These variations have been attributed to the lack of quality control on the bulbs, design of the cap lamp head piece and in some cases, poor maintenance.In 1986, a series of underground tests were conducted to establish the minimum light output from cap lamps required to visually identify loose ground. The results of these tests indicated that a cap lamp should produce a minimum peak illuminance of 1500 lux measured at 1.2 metres from the light source. On May 30, 1987, Ontario became the first province in Canada to legislate the minimum amount of light required to visually assess ground conditions. INTRODUCTIONPoor lighting has been identified as a factor which can contribute to mining accidents. Over the past decade, several Coroner's Juries as a result of inquests into mining fatalities, have recommended improved lighting in mines.The Joint Federal-Provincial Inquiry Commission into Safety of Mines and Mining Plants in Ontario, was appointed to report upon the adequacy of existing arrangements and practice s that may affect safety. This Commission completed their report in April 1981, and recommended that inadequate lighting be investigated as a possible cause of all reportable underground accidents, and that a comprehensive research programinto mine lighting be undertaken.In response to the first recommendation, the Mining Health and Safety Branch of the Ministry of Labour, hereafter referred to as the Branch, initiated a program to measure lighting levels in all fatal accident investigations where inadequate lighting was a possible factor."

Jan 1, 1989