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By Ian E. Efford

The paper gives an assessment of Canada's energy supply-and-demand position, the current situation and projections into the future, as well as a review of some alternative energy futures for Canada. The main elements of Canada's energy strategy for the period 1977-1990, with particular reference to the role of energy conservation, are discussed, leading in to the development of the national energy conservation program.

Jan 1, 1977

By K. C. Lahiri, H. P. Das, G. G. Sarkar

"The petrographic components of any particular rank of coal often show some distinct physical and chemical characteristics. Therefore, their pro-portionate distribution in a coal greatly influences the technological behaviour of the coal.In any size or gravity separation of a coal, the petrographic constituents become segregated to different degrees in some preferred size or specific gravity range. Therefore, a knowledge of the petrographic nature of the washed and/or screened fractions is often considered essential in selecting the most efficient method for coal preparation and in exploring the proper evenues for its utilization.A graphical method is described in this paper to indicate the mineral-matter content and the petrographic components of the washed fractions of a coal at different ash levels of separation in the form of a new washability diagram. This diagram can be conveniently used to assess or predict the petrographic composition of clean coal or sinks corresponding to any desired ash level in the cleans. With the help of this diagram, it is also possible to locate the yield level of cleans at which maximum enrichment of vitrinites and exinites occurs with the least amount of mineral-matter content."

Jan 1, 1971

By R. D. Brown

"Finance Minister Donald Macdonald's budget of May 25, 1976 featured a restructuring of the anti-inflation profit controls and a grab bag of tax changes, some of direct interest to the mining industry. All Canadian taxpayers now will be permitted to write off immediately 100% of mineral and oil and gas exploration expenses included after• May 25, 1976 and before July 1 1979. The cost of acquitting Canadian resource property after May 6, 197.4 from a federal or provincial government will now clearly be included in Canadian development expense, and provincial drilling and exploration incentives received after May 25, 1976 will not reduce exploration and development expense for federal income tax purposes. Under tough new anti-inflation profit controls, all controlled businesses, except distributions, will essentially have one uniform set of rules for• determining allowable profit margins; this allowable margin will be determined by product line or by over-all net margin and will be 85% of the higher of the margin obtained in the five years preceding October• 13, 1975 or the one year preceding May 1, 1976. The basic capital cost allowance system is to continue, but many rates will be revised. The ability to offset losses created through claiming capital cost allowances on leased equipment, etc. against other income will be ended with respect to transactions entered into a/te1• budget night. Miscellaneous other tax changes will raise the low rate base for Canadian-controlled private corporations to $750,000 increase retitement plan contribution limits and reduce the rate of branch tax imposed on branches of corporations resident in a country with which Canada has a comprehensive tax treaty to equal the withholding tax rate on dividends under that treaty."

Jan 1, 1976

By Elaine R. Goetz

The eastern and southeastern regions of Ohio are part of Appalachian coal country, with a documented 1,300 miles of streams impacted by acid mine drainage. Since 1995, partnerships of local watershed groups, government agencies, private industries and universities have focused on the remediation of the affected waterways. The partnerships have spent $2.4 million annually in constructing and operating treatment systems such as wetlands, anoxic limestone drains, successive alkalinity production systems, steel slag leach beds, and lime dosers. These systems have been partially successful, and water quality has improved in the region, but no treatment has yet met the ultimate objectives of low cost, continual remediation. Our research group has investigated an alternative system for acid mine drainage treatment: electrolysis combined with pH adjustment to selectively precipitate recoverable, saleable metal products to offset the cost of treatment. We utilized a $0.2 million pilot facility constructed by the Wayne National Forest, in Nelsonville, Ohio, to process approximately 40 L/min of mine drainage from surrounding seeps. The pilot facility has multipurpose tanks that can be adapted to process acid mine drainage with different characteristics, such as high or low aluminum content or high or low carbonate concentrations. Sodium hydroxide was used for pH adjustment. Results indicate that saleable product can be generated with this treatment technology. In an initial, not optimized trial, one seep yielded 4.7 kg of dried 69 % iron oxide product from 10 hours of pilot facility operation, treating 23,000 L with electricity costs of $4.68. Dissolved iron concentrations in the water were reduced from 242 ± 18 mg/L to 2.8 ± 2.0 mg/L (99.0 % removal) while the initial acidity of 443 mg/L as CaCO3 was neutralized to an alkalinity of 160 mg/L as CaCO3. Iron oxide can be sold as pigment for an average of $1.47 per kg in the United States. Currently, approximately 80 % of all pigment used in the United States is imported, and there is incentive to purchase domestically recovered pigment. If the iron oxide from the pilot facility could be sold as pigment for $1.47 per kg, 43 % of the operating cost (raw materials, electricity and construction costs) of treatment could be offset by the sale of the product. Considering the cost offset, the electrolysis process shows potential as a sustainable low cost alternative for treating acid mine drainage.

Aug 1, 2013

By Songgen He, Jianchun Guo

With the development of complex, unconventional and deep reservoirs, it shows that many rocks behave plastically with the influence of clay and confining pressure. Traditional linear elastic hydraulic fracturing initiation models are not good predictors for elastic-plastic reservoirs. With the deformation theory of plasticity, a power hardening constitutive equation was developed in piecewise approximation method. Based on the nonlinear constitutive equation, a model of the stress field around the wellbore was developed considering fracturing fluid penetrating effect and in-situ stress anisotropy. At last, coupled with the maximum tensile strength criterion and Mohr-Coulomb criterion, a new elastic-plastic hydraulic fracturing initiation model was built. The following conclusions were summarized in the paper: (1)The piecewise power hardening constitutive equation based on the deformation theory of plasticity can accurately describe the nonlinearity of elastic-plastic deformation. (2)Whether the rock is yielded or not is determined by in-situ stress, yield stress, Biot coefficient and pore pressure. (3)Plastic yield has little influence on radial stress but significant impact on circumferential stress. The radius of the plastic zone is positively correlated with in-situ stress but negatively correlated with yield stress, power hardening index, pore pressure and Biot coefficient. (4)Initiation modes include tensile failure and shear failure when rock is yielded. (5) For elastic-plastic reservoir, the initiation pressure predicted by linear elastic model is much lower if the rock is yielded.

Jan 1, 2015

By J. Lui

At its Copper Cliff Smelter, bulk nickel and copper concentrate is processed in two Inca flash furnaces and Peirce Smith converters to produce Bessemer matte containing 0.6%Fe. After slow cooling and Matte Separation, Bessemer matte is converted into three main products using magnetic separation and flotation technology: (1) a nickel containing chalcocite concentrate (MK); (2) two types of copper containing nickel sulfide (ME and MR); (3) metallics (MYN). MK is further processed in the Inca top blowing bottom stirring MK Reactor to produce semi-blister copper containing ~4%Ni and ~3±1 %S. The semi-blister copper is then purified in the multi-purpose vessels (MPV) to produce blister copper by reducing Ni, Fe and S content through oxidation. High melting point NiO is formed inside the MPVs. The accumulation of solid NiO and other oxides requires periodic cleaning by adding reductant and furnace matte, a unique process called "washout" at Inca. For many years, the reductant used for the "washout" process has been 15%Si Ferro-silicon. With increasing cost and limited suppliers for 15%FeSi, alternative reductants were pursued. This paper summarizes the development and commercialization of new alternative reductants for MPV "washout".

Jan 1, 2007

By K. C. Grogan

"GeneralGIANT ORE is complex, with the gold values for the most part occurring in extremely close association with arsenopyrite, stibnite, jamesonite, and a wide group of antimonial minerals locally termed 'the grey minerals'. Pyrite is the most abundant of the sulphide minerals• and minor quantities of chalcopyrite, galena, and sphalerite also occur. Pyrrhotite has been found in some sections of the mine, but to date none of it has been nickeliferous. Native gold occurs in varying amounts throughout the ore bodies.In 1944, ore dressing investigations were commenced on diamond-drill core rejects and samples of surface outcrop ore. Results soon indicated that treatment to produce satisfactory recovery of the gold values would involve fine grinding to 80-85 per cent minus 200 mesh, recovery of free gold by jigs, followed by flotation, roasting of the flotation concentrate, and subsequent cyanidation of the calcine. Proceeding from this information, the flow-sheet was prepared, plant design worked out, equipment purchased, and construction of the treatment plant commenced in May, 1947.The crushing, grinding, and flotation units of the plant were rushed to completion and commenced operation on May 12th, l.948, at 225 tons of ore per day. This rate was maintained until January 27th, 1949, when the Allis-Chalmers roaster and cyanide plants were completed and commenced operation. During the period May 12th, 1948, to January 27th, 1949, gold recovered by amalgamation was the sole source of revenue. Flotation concentrate was stockpiled pending the completion of the Allis~Chalmers roaster and cyanide plants."

Jan 1, 1953

By J. Paturaud, A. G. Villemiane, J. Y. Buffiere, D. Fabregue, M. Perrier

In this work, a detailed characterization of the cyclic damage mechanisms on duty in car heat exchangers has been carried out in order to improve their reliability. The material which consists in very thin (<0.3 mm thick) sheets formed of 3 co-rolled aluminum alloys (4045 /3916/ 4045) has been brazed in order to obtain metallurgical and surface conditions representative of those of the real components. Fatigue tests at constant stress amplitude have been performed at room temperature and 120°C in order i) to characterize the cyclic resistance of the studied materials and ii) to study the effect of temperature on the fatigue damage mechanism. The mechanisms leading to failure have been identified from post mortem fractographic analysis. The Wohler curves obtained show that, contrary to common structural Al alloys, this type of thin sheet brazed multi material can be cycled for several hundred thousand cycles at very high stress level (> ~ 80 % of the tensile strength). This behaviour is analysed with respect to the microstructure resulting from the brazing process and the low number of grains present in the sample thickness (around 5 grains).

Jan 1, 2015

By H. J. Chalmers

THE H.B. MINE and concentrator are located in the Nelson Mining Division of British Columbia, on the north side of the Sheep Creek valley about seven miles southeast of the town of Salmo. It is an operation of The Consolidated Mining and Smelting Company of Canada, Limited (Cominco), which has its metallurgical plants at Trail, about 25 miles west. The property was originally staked about 1907 by Horton and Benson, whose names are commemorated in the designation "H. B." Up until 1927, a considerable amount of development work was done in the upper levels by various companies. Cominco purchased the ?property in 1927 and carried out intermittent work until 1946. Following this, an extensive surface diamond drilling programme and a subsequent underground exploration were undertaken. Sufficient ore was outlined &apos;to warrant the construction of a 1,000: ton concentrator. This was started in April, 1952, and completed by the spring of 1953. However, because of adverse base metal market conditions, operation was deferred until May, 1955.

Jan 1, 1957

By M. Dupuis

Recently, a new approach to controlling alumina feeding in a H.H. cell has been proposed [1, 2 and 3]. This approach, labeled In Situ aluminium cell control, is based on a correlation between the slope of the cell voltage during a no feed observation period and the dissolved alumina concentration in the bath. Once the dissolved alumina concentration has been estimated, a primary calibration surface uniquely relating the dissolved alumina concentration and the anode-cathode-distance (ACD) to the cell voltage is used to estimate the cell ACD. Once both the alumina concentration and the ACD have been estimated at the end of the observation period, a PID controller can be used to regulate the rate of alumina feeding using only the normalized cell voltage to calculate the error between the estimated dissolved alumina concentration and a target value. The In Situ aluminium cell control algorithm has now been tested with the Dyna/Marc [4, 5 and 6] cell simulator demonstrating that it should be possible to control a H.H. cell in this manner with less variation in the dissolved alumina concentration and other process variables producing a prediction of improved cell current efficiency and power efficiency.

Jan 1, 2011

By Hans Lundberg

PREFACE THE successful conclusion of all geophysical work depends on the operator&apos;s skill and sound judgment, as well as on his knowledge of geology and geophysics. We have been fortunate enough to have as co-workers a number of very good men. Some results of their work are summarized in this paper, and it is a pleasure to acknowledge their cheerful spirit of co-operation and the enthusiasm and loyalty with which they have assisted in the building of a geophysical organization to serve the Canadian mining industry HISTORY Geophysical prospecting is commonly, but quite erroneously, regarded as something new. The name is modern, but the principle of applying physical laws to reveal the presence of hidden ore is several hundred years old. Already, at the beginning of our civilization, the need was strongly felt for methods that could indicate the presence of ore in regions where the ore-bodies were completely masked or hidden from the eye. Particularly in countries where the rocks have been eroded during periods of glaciation and later covered by a thick mantle of glacial debris, all kinds of mysterious schemes were invented to locate the hidden ore. Often magic was resorted to (for example, the divining rod), but methods based on sound principles were also developed. Such features as topography, colour and taste of surface waters, and the growth and occurrence of trees and plants, were used to reveal certain types of ore deposits. For finding bodies of iron ore, the compass was very early in use. The fact that objects of iron attract a compass needle was utilized in prospecting long bef01:e the time of Columbus, and a systematic search for bodies of iron ore by this method was organized as early as the year 1600. There are still in existence documents, dated a little over 300 years ago, which show that the Swedish Chancellor of that day, Axel Oxenstiorna, ordered dozens of sun-dial compasses from instrument makers in Germany. The Swedish Government at that time employed a great number of prospectors to search systematically for iron ore. This Government undertaking must have been quite successful, as a number of iron ore-bodies were found in areas covered by heavy overburden. These prospectors were simply Government &apos;geo-physicists&apos;, although they were not known by this fancy name.

Jan 1, 1937

By J. Defreyne

CESL has developed a proprietary hydrometallurgical process for base metal concentrates, notably those of copper and nickel. The process is based on pressure oxidation (PO) of the sulphide minerals, which is done at elevated temperatures in mixed sulphate-chloride liquor at about pH 2 ? 3. The process achieves maximum oxidation of the metals whilst minimizing sulphur oxidation to sulphate. Almost all base metal sulphide minerals are efficiently treated under these conditions. In the case of copper minerals, pressure oxidation does not generally put the copper into solution, because of the relatively high pH prevailing in this process. Therefore, PO is followed by an acidic leaching stage, which specifically aims at maximum copper dissolution with minimal leaching of iron. The overall copper recovery is largely determined by the efficiency of this stage. The process has low capital and operating costs, partly because there is minimal use of acid or neutralizing agents for iron dissolution or precipitation, respectively; this is achieved by minimizing iron leaching during both the oxidation and leaching stages. Iron sulphides in the feed concentrate deport almost entirely to the solid leach residue as hematite, which has superior handling characteristics for filtering and washing. Iron minerals play a key role in the process, with pyrrhotite and pyrite having very different responses to the oxidation process. Acid management for the whole process is affected by the iron mineralogy, and the flowsheet is therefore tuned to the specific concentrate.

Jan 1, 2006

By P. L. Li, B. X. Song, C. H. Wang, T. Wang, Z. Hu

"The treatment of an oxidized copper-gold ore by stage cyanide addition was investigated. For cyanidation, free cyanide ion concentration can be an indicator of whether there is copper dissolved in cyanide solution, and maintaining the free cyanide ion concentration lower than 1.0 g/L could be an effective way to prevent copper dissolution and reduce cyanide consumption. For that purpose, stage cyanide addition was introduced to control free cyanide ion concentration within the range from 0.8 to 1.0 g/L. Cyanidation tests results indicate that gold extraction was still acceptable at reduced cyanide consumption with a lower copper extraction. Based on the experimental study, industry application works at Beiya concentrator of Yunnan province, China were successfully conducted. When the raw ore contains 2.95 ppm Au and 0.75% Cu, by stage cyanide addition method, the gold extraction was still 93% at reduced cyanide consumption of 2135 g/t, which was only half of one addition method, and the copper extraction dropped to only 5%, which indicated that dissolution was prevented for almost 75% of the malachites.INTRODUCTIONCyanide with its competency to form a strong complex with gold, is the most preferable lixiviant for gold leaching. However, cyanidation is not inherently a selective process since many other minerals present in the ore are also readily soluble, especially the copper minerals. Muir (2011) reported that every 1% reactive copper present in the ore consumes about 30 kg/t NaCN, which can have detrimental effects on the process efficiency and economics due to high cyanide consumption, reduced gold leach rates and poor gold recovery."

Jan 1, 2016

By H. Jung

The microstructures and grain sizes of nanocrystalline Co and Co-1.1 wt % P alloys were characterized by X-ray diffraction. The corrosion properties of as-deposited and annealed Co-l.l wt % P alloys and pure nanocrystalline Co were studied in a deaerated 0.1M H2SO4 solution using electrochemical measurements and XPS surface analysis. Potentiodynamic polarization testing and impedance measurements revealed that an addition of P to pure nanocrystalline Co improved the anodic-corrosion resistance, however, this enhanced corrosion resistance was compromised by the heat treatment process at 350 and 800°C. The corroded surface of annealed nanocrystalline Co-1.1 wt % P at 350°C exhibited a more porous P-enriched layer compared with the as-deposited case. A sample annealed at 800°C corroded uniformly showing second-phase precipitates. The enhanced corrosion resistance of as-deposited nanocrystalline Co-1.1 wt % P was attributed to the elemental P on the surface that acted to hinder the anodic dissolution kinetics of surface Co following an initial selective dissolution of Co. However, at a higher anodic overpotential region, the superior corrosion resistance of Co-l.l wt% P alloys did not last because of the formation of a non-protective surface film consisting of mainly hypophosphite and phosphate as well as elemental P.

Jan 1, 2005

By P. R. Goad

"Kidd Creek is a large volcanogenic base metal sulphide deposit, located near the west end of the Abitibi greenstone belt, 27 km north of Timmins, Ontario. The rhyolite geology is characterized by a NNE-striking and steeply east-dipping package of rhyolite volcaniclastics upon which has been imposed a strong ESE-striking and north-dipping structural fabric . Massive rhyolite units with grey-black. chloritic cores and yellow, sericitic margins intrude as dykes into the stratigraphic footwall and as sills higher in the stratigraphy. Massive rhyolite units positioned near the top of the felsic pile exhibit an extensive marginal development of hydraulic fracturing and are termed crackle-brecciated rhyolite.The stringer sulphide zone is positioned in a lobate blanket of crackle-brecciated rhyolite at the top of the felsic pile. The stringer sulphide zone is characterized by a mature chemical alteration, being specifically depleted in alkalis and enriched in iron-rich chlorite. with accompanying silica, sericite and carbonate alteration. A suite of trace elements characterizes this mature alteration. The massive rhyolite units, which intrude lower in the rhyolite volcaniclastics, exhibit a core of weak chlorite alteration and strong marginal sericite alteration. Tight or unfractured massive rhyolite units are essentially devoid of sulphide mineralization and exhibit a suite of trace elements characteristic of this immature alteration. It is interpreted that the massive rhyolite units intruded into an already evolving system and ""choked-off"" active conduits carrying hydrothermal fluids and subsequently acquired an immature alteration signature. Rhyolite units positioned higher in the pile developed intense hydraulic fracturing and a mature alteration coincident with the formation of the stringer sulphide zone. In summary, a model, based strictly upon the rhyolite geology, is reviewed to assist in the exploration for volcanogenic base metal sulphide deposits."

Jan 1, 1985

By A. Mazhary

"Although sensor-based ore sorting has gained significant attention recently, sorting gold deposits still face a high level of skepticism by gold mining companies. In order to shed some light on the matter, this article looks at two different gold deposits that were examined using X-ray Fluorescence, Electromagnetic and X-ray Transmission sensors. The heterogeneity of each sample is measured based on the assay results of each particle and is related to its sortability. Multivariate linear regression analysis was also performed on the XRF results to find potential proxy elements for detecting gold. The results from these deposits were varied and each sample showed different levels of sortability. While both X-ray sensors proved efficient for different deposits, the electromagnetic sensor failed to produce any promising results. Despite unsatisfactory result for one sample, this technology can have significant advantages in terms of lowering the operational costs and improving head grades and recoveries providing that the deposit is amenable to such separation methods. Therefore, it is important to mention that sensor-based ore sorting is ore and sensor dependent, and as a result, it cannot be applied and be beneficial to all deposits. Therefore, amenability tests are required in order to examine the potential for sensor-based ore sorting before one can reject the idea.INTRODUCTION Although sensor-based ore sorting has gained significant attention recently, sorting gold deposits still face a high level of skepticism by gold mining companies. Except for a few cases presented previously, no new case studies have been published. Previously, mines such as Kloof Gold Mine in South Africa used an optical sorter to sort their waste stockpile in 2003–2004 (Von Ketelhodt, 2009) and then again in 2009 (Von Ketelhodt, Falcon, & Falcon, 2011). More recently, Coeur Operations utilized an XRT sorter for their Kensington Mine in Alaska (Lasley, 2014) and also Anglo-American Platinum used an XRF sorter to pre-concentrate Platinum Group Metals through an algorithm that used chrome, copper and nickel as proxies (Rule, Fouchee, & Swart, 2015)."

Jan 1, 2017

By Rejean Gagnon, Fernand Rochefort

"Haulage costs, in most operations, represent a large portion of total cost. Quebec Cartier Mining Company came to the conclusion t hat an electric trolley assist providing more horsepower than available from dieselgenerator sets presented the best oppor tunity for improvement. Accordingly, a testing and development program was carried out which resulted in the design, installat ion and application of a practical system. This paper describes the development of the system, the equipment used as well as the actual operation. A projection is also made to indicate further improvement in productivity. A comparison is made of truck operating data before and after activation of the trolley assist system in order to determine its economic impact."

Jan 1, 1972

By Jochen Petersen, Jean-Paul Franzidis, Allan Nesbitt

This study presents a method for the determination of intra-particle diffusivities in ion-exchange resins for the purposes of evaluating the state of resin degradation during service. The method uses a zero length column (ZLC) in a closed circuit with variable speed pump and reservoir. The intra-particle diffusion is determined from absorption data by using the Nernst-Plank approximation along with the ‘mass transfer factor’ - which is a product of the mass transfer coefficient (kf )and the concentration of the adsorbing ion in the liquid at the surface of the resin - in a computer algorithm fitting simulated curves to experimental data.. Through this approach the changed intra-particle diffusivity, of a gel-type acid resin, over a 1000 loading and elution cycles, is shown.

Jan 1, 2014

By Reik M. Winkel

Radar Technologies are successful implemented in the military industry since decades and recently found their way in the mining industry as level gauge radars for bin applications. The latest generation of microwave radar sensors are capable to provide geometrical data of the surrounding area of mining machines, too. Radar sensors are an improvement to laser scanners as they are more robust and able to penetrate dust and mist. Radar sensors will be the key source for operator assistance systems. indurad and RWTH Aachen University conducted a large series of tests at open pit mines and underground coal mines to determine the potential of the new two dimensional Dual Range Radar iDRR. Several applications were determined as highly feasible and are now completed respectively in the implementation stage. The authors are giving an insight in the experimental results, the implementation and an outlook of future applications for this technology.

Oct 1, 2009

By John J. Jonas, Hong Qin

Cylindrical samples of pure titanium were subjected to uniaxial compression at room temperature, leading to the formation of three generations of twins. Many primary contraction twins were observed as the initial texture was favourable for their formation. Numerous secondary extension twins formed within the primary contraction twins and some tertiary contraction twins within the secondary extension twins. The orientations of these three generations of twins were determined by electron backscatter diffraction techniques and their associated Schmid factors (SFs) were calculated. The formation of the twin variants selected in each generation and the absence of certain potential variants are accounted for by rotating the twinning displacement gradient tensor expressed in the twin system reference frame into the crystallographic reference frame of the relevant neighbouring grain. The presence of the observed primary, secondary and tertiary twins is explained in terms of the ease of imposing the required accommodation strains on the neighbouring grains. By contrast, certain first, second and third generation potential high SF twins were absent because their formation would have required accommodation by the most difficult deformation mode: pyramidal glide.

Jan 1, 2015