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By J. J. Baz-Dresch

"The Cannon Mine, a joint venture between Asamera Minerals (the operator) and Breakwater Resources, is located in the centre of Washington state at the eastern base of the Cascade Mountains. The mine complex is located three blocks south of the city limits of Wenatchee, part of an urban area with a total population of 47 000. The closest residence is 350 feet from the mine portal.The B-Neath zone is a narrow, high-grade, downward extension of the southern tail of the mine's main ore body, the B-North zone. It also underlies the northernmost portion of the B-West zone (Fig . I) . The ore is usually reasonably competent but completely surrounded by very weak rock consisting of shear zone and unsilicified sandstones and siltstones.The zone has maximum dimensions of 420 ft in thickness, 500 ft in length , and 200 ft in width . The economic reserves extend from the 70-ft elevation (elevation above sea level) to the 630-ft elevation and consist of about 1.3 million tons of geologic reserves (proven and probable) at an average grade of 0.33 ounces per ton.Acquisition and ExplorationInitial DiscoveryThe initial discovery of the B-Neath zone was made by Tenneco Minerals during July through September, 1984. Their 22-hole surface drilling program consisted of 18 200 ft of drilling. Tenneco Minerals had acquired the 91/2 acre lease from United Mining Corporation.Asamera Minerals subsequently purchased Tenneco's lease in July, 1985; Tenneco retained a royalty position which was later purchased by Echo Bay Mining.Follow-up drilling by Asamera Minerals consisted of both surface and underground drilling. Eight surface holes (7200 ft) were drilled commencing in December, 1985. Following evaluation of the geologic data, an access drift was driven on strike along the top of the ore zone on the 500 level. Diamond drilling from this platform consisted of 17 200 ft in 79 holes."

Jan 1, 1990

By B. Jin

Removal of fluoride and chloride by alkaline washing from direct lead smelting dust which originated from an Ausmelt furnace is reported. The results show that the fluoride removal efficiency increases with an increase of alkaline concentration, alkaline washing temperature and time. The L/S ratio has little effect on fluoride and chloride removal efficiency. A new flow sheet for removal of fluoride and chloride from the dust was successfully proposed according to the results. Fluoride and chloride removal efficiencies are more than 53.68% and 63.18% respectively using the flow sheet under the optimum parameters of temperature 338 K, L/S ratio 3:1 and alkaline washing time of 1.5 h. The contents of fluoride and chloride in the alkaline washing residues can meet the standard of zinc purity as hydrometallurgical materials for zinc processing.

Jan 1, 2014

By Paul Guliov

Coal-bearing Tertiary sediments of the Ravenscrag Formation in southern Saskatchewan host numerous deposits of clinker resulting from in situ coal combustion. Clinker deposits form when sediments of relatively low temperature firing properties overlie coal seams which are undergoing prolonged spontaneous combustion. The resulting fired material is useful for decorative landscaping aggregate, rock gardens, driveways, mud control and others. Predicting the occurrence of clinker deposits requires a knowledge of the spatial distribution of coal seams and the nature ofoverlying sediments. Knowledge ofpaleotopography at the time of coal combustion can assist in locating more highly-fused material which can yield greater block sizes. Coal data bases can be used as a predictive tool by outlining areas where coal is or was at or near surface and therefore may have been susceptible to spontaneous combustion.

Jan 1, 2001

By K. Parameswaran

This paper builds on presentations made at the Conference of Metallurgists (COM) 2015, COM 2017 and Extraction 2018 and associated papers published in the respective conference proceedings. Based on the classic Brundtland Commission definition of sustainable development as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs,” the paper describes how metal mining can be compatible with sustainable development and how sustainability considerations have been applied in the primary copper industry, using several examples of sustainable mining practices from ASARCO LLC operations. Finally, the paper discusses how these considerations might be used in the future by discussing the need for developing a sustainable development strategy and how this strategy can be aligned with the United Nations Sustainable Development Goals. INTRODUCTION The primary copper industry comprises: mining (also referred to as “extraction”); mineral processing (also referred to as “beneficiation, “milling” or “concentration,”) which includes leaching, solvent extraction (SX), crushing, grinding, froth and flotation operations; and metallurgical processing which includes smelting and converting; refining, which includes fire-refining or anode refining and electro-refining; and electrowinning (EW). There are two routes for producing refined copper: hydrometallurgical and pyrometallurgical. The hydrometallurgical route comprises mining (open-pit and underground), mineral processing (crushing and grinding — for heap leaching only; leaching and SX) and metallurgical processing (EW). The pyrometallurgical route involves mining, mineral processing (crushing, grinding and froth flotation) and metallurgical processing (smelting, fire refining and electro- refining). The primary copper industry is capital, water, resource and energy intensive with the potential for significant environmental impacts, if the environmental aspects are not properly managed. ASARCO LLC (Asarco) was organized in 1899 as the American Smelting And Refining Company. Originally a consolidation of several lead-silver smelting companies, it evolved over the years into an integrated producer of primary non-ferrous metals, including copper, lead and zinc and associated co-products. Grupo México, S.A.B. de C.V (Grupo México) acquired Asarco in 1999. Today, Asarco is a vertically integrated producer of primary refined copper and associated co-products such as gold, silver, selenium and tellurium. Asarco operates three open-pit mines and mills, two leach, SX-EW plants, a copper smelter in Arizona and a copper electrolytic refinery in Texas.

Jan 1, 2019

By A. A. de Gast, R. B. James

"The metal content of ore blocks can be calculated by the use of many different methods. These methods range in sophistication from manual calculation to computer. oriented techniques. In this case a cubic polynomial regression model is developed to depict the grade distribution of an orebody. Mine production, in stope dimensions, is then simulated on a computer to predict the output of metal content. The volume, grade and variance of the grade are estimated by triple integration and matrix algebra. A case study shows reasonable agreement between the results from the mathematical model and the mine geologists' estimate of production and ore reserve grade and tonnage."

Jan 1, 1972

By B. M. Monaghan

"The developments of the 1950s and 1960s have seen Canada become an international source of iron ore, trading in all geographical areas and hemispheres. Canada's production will significantly increase in the next decade. However, although the outlook is bright, iron ore producers cannot be complacent. Instead, we must weigh the factors that have brought about the development of the Canadian iron ore industry and examine the probable changes for the next decade that will affect its growth.Looking ahead in the 1970s, competition will be severe. Pressure on prices will continue as new sources of supply bid for long-term contracts and as steel producers continue to develop mines around the world. Rising costs will make these pressures more severe. We must balance the growth of the world's steel makers with the emergence of new supplies of iron ore. The iron ore industry is now part of a new era in which demand and supply are intermeshed, and the developments around the world are acting on the Canadian iron ore industry's future."

Jan 1, 1971

By Robert E. Loftus

"The author discusses the growth in the use of ocean-going bulk carriers for the transportation of mineral commodities, and predicts future trends. The various types of tonnage carriers are described, along with the special discharging gear used, the costs involved and the duties of some of the personnel.THE FIRST CONSIDERATION in planning the ocean transportation of minerals is the type of vessel to be utilized. The modern 'Bulk Carrier' bas proved to be the most successful vehicle for the purpose. I would there-fore like to describe this fleet in some detail and at-tempt to show the impact that the bulk carrier bas bad on the movement of bulk materials."

Jan 1, 1968

By Eddy Dénommé, Deni Villeneuve

"Niobec mine, a producer of pyrochlore concentrates since 1976, became a producer of ferroniobium in 1994 and achieved accreditation to the ISO 9002 standard in 1995. The goal of ISO 9002 is to ensure that the products supplied to clients regularly meet their specifications, through explicit work standards and procedures throughout the production process, from deposit appraisal to ferroniobium production.A key element of ISO 9002 implementation at Niobec consists of the quality control procedures applied to the raw materials: the ore fed to the mill and the pyrochlore concentrate fed to the reduction plant. These controls extend from exploration, deposit appraisal, mine planning and reserves estimation, mining, mineral processing and, finally, ferroniobium production. The implementation of ISO 9002 has allowed more efficient control of the quality of the final product sold to clients. It requires interactive team work, the role of the geologist being to relate all information pertaining to raw material and product quality to the geological framework of the deposits."

Jan 1, 1997

By A. R. Sorta, D. C. Sego

ABSTRACT Temperature, solute, texture, and thixotropic effects on time domain reflectometry (TDR) measurements of water content in oil sands tailings are investigated. Results indicate that TDR water content measurements are influenced by temperature, residual bitumen, and percent clay in the tailings. A correction of 0.03–0.10/ °C must be applied to the apparent dielectric constant (Ka) to account for the effect of temperature. The Ka-volumetric water content relationships of slurries differ significantly from the commonly used Topp calibration equation. The age of the tailings and the addition of phosphogypsum did not influence TDR water content measurements.

Jan 1, 2013

By S. R. Stopic

The EU-financed INTREAT Project (Integrated treatment of industrial wastes to¬wards prevention of regional water resources contamination) addresses the environmental pollution associated with solid and liquid wastes/effluents produced by complex sulphide ore mining and metallurgical activities. The results concerning the electrolytic recovery of cop¬per from effluents formed after mixing of streams from Copper Refining, Precious Metals Plant and Electrolyte Regeneration in the Balkan Area will be shown. The waste water is characterized by low pH values and high contents of heavy metals, such as Cu, Ni, Bi, As, Sb. The majority of these waste water flow untreated into the natural water streams and through the network of existing rivers, which end up in the river Danube. The influence of current density and flow rate on the deposition rate, the quality of copper and the process efficiency will be presented. The full continuous process is based on cells with rotating disc cathodes and represents a pre-treatment step before common neutralisation in a cascade line

Jan 1, 2007

By A. D. Hunt

THIS PAPER will review Canada's fossil fuel situation as we understand it today and indicate some of the options available to meet our energy requirements during the next 15 years. It would therefore be helpful to examine Canada's total energy requirements and discuss the un certainties of the data base on which we must base future energy investment decisions. On the world scene, Canada is at the top of the energy-consuming nations, using about 49 bbls of oil equivalent per caput/ year. This appears to be slightly ahead of the U.S. and of course much higher than that of many countries. It is generally accepted that there is a more or less direct relationship between energy consumption and material standard of living. However , as we know, Canada, when compared with other industrialized countries on a GNP, an individual-income or some other standard basis, is lower in the list. This situation may be explained by our more severe climate and a relatively small population distributed over a land mass second only to that of the Soviet Union.

Jan 1, 1977

By Alfred W. G. Wilson

In this paper is presented a review of the changes that have taken place in certain Canadian non-metallic mineral industries since 1909. The fifteen-year period 1909 to 1923, inclusive, has been selected for two reasons. In the first place, statistical treatment of the subject under review has been nearly uniform throughout the period. In the second place, this decade and a half is itself further subdivisible into three well marked quinquennial periods, the middle one covering the period of the great war when industrial conditions were greatly disturbed. It then becomes possible to institute certain comparisons between equal periods before and after the war disturbances. The items selected for inclusion in this review are certain of the more important members of that class of minerals usually grouped together under the heading of non-metallics. They are all minerals of which Canada is known to possess important resources, and which are indispensable to many of our greatest manufacturing industries.

Jan 1, 1925

By R. K. Netolitzky

The Weedy Lake, Tower Lake, and Wedge Lake gold deposits illustrate contrasting styles and different ages of mineralization within the same district. The discovery of these deposits was the result of systematic exploration of gold occurrences noted during research of assessment files. The Weedy Lake and Tower Lake depo its reflect a late-stage gold mineralizing event. The e deposits developed along the same major structural break, and also display simi lar mineralogy and alteration patterns. Mineralization is developed in all the lithologies present. The Wedge Lake property, while having occurrences similar to the Weedy and Tower deposits. has the more important Twin Zone which best fits a volcanogenic exhalative model. The Twin Zone has a complex structural history without a recognizable alteration halo. The setting may be proximal to a hydrothermal vent. Mineralization is hosted within a mixed ulphide/oxide/silicate facies iron formation breccia. and the gold is intimately associated with arsenopyrite. The origin and age of the brecciation is key to understanding the mineralizing event. Traditional prospecting procedures in conjunction with conventional B-horizon soil geochemistry were instrumental in the Twin Zone and Weedy lake disco,•eries. Tower Lake was a prospecting discovery partially defined by previous drill programs. This deposit was also identified by B-horizon oil sampling.

Jan 1, 1986

By Joseph U. Messenger

A method of applying ammonium hydroxide to a drill stem containing hydrogen sulphide gas and hydro-gen-sulphide-bearing oil and water so as to remove the hydrogen sulphide as ammonium sulphide is de-scribed. It was concluded that the method allowed trips with drill pipe filled with sour fluids to be made more safely, more rapidly, and more economically. INTRODUCTION THE DANGER of poisoning rig crews during drill stem tests of sour wells by exposing them to hydrogen sulphide gas is well known in Canada. Concentrations of hydro-gen sulphide in sour gases range from 0 to 40 volume percent. There have been numerous casualties from hydrogen sulphide exposure during drill stem testing. Some have resulted in permanent injuries; in some cases the injuries have been fatal. For example, in Alberta in 1957 there were four deaths and 100 exposures which required medical treatment. These fatalities and injuries indicate the need for a more effective way of handling hydrogen sulphide in oilfield operations.

Jan 1, 1958

By G. Van Weert, O. Wang

"As part of a general review of processing double refractory ores through Barrick Gold’s autoclaves / CIL facility at Goldstrike, blanking the preg robbing native carbon in the process solids with hard (m.p. 55 - 60 º C) paraffin wax was studied, specifically in relation to pressure oxidation. The improvement in CIL gold extraction was found to depend on the wax addition point, with hot, dry contacting of the ore in the presence of wax - prior to POX - yielding the largest, most consistent improvement in gold extraction.INTRODUCTIONDouble refractory gold ores present two barriers to gold extraction. The first is generally a physical barrier: the gold is encapsulated or dispersed in a matrix which is impervious to the gold lixiviant. In most cases, including Carlin Trend, NV, deposits, this involves a pyrite or arsenopyrite matrix, although minor gold may also be dispersed in competent silica (quartz) or iron oxides. Gold can be rendered accessible by oxidative destruction of such sulphide matrices. At Goldstrike this is practised by roasting and autoclave oxidation (Thomas, 1994). It is the latter route to which this paper refers.The second barrier refers to the actual gold recovery. Gold may be extracted from the pressure oxidized solids with cyanide, forming a gold cyanide complex. One characteristic of this complex is that it adsorbs on graphitic surfaces. This is taken advantage of on a large scale by gold millers, who use manmade activated, i.e., graphitized carbon particles to remove the gold from solution during leaching: the Carbon-In-Leach, or CIL process. The gold cyanide bearing carbon particles are larger than the ore solids and can be separately recovered by screening. Goldstrike uses the CIL technology to recover gold. The second barrier becomes problematic when the ore naturally contains graphitic orcarbonaceous material, hereafter referred to as native carbon (versus the man-made activated carbon). This material may also adsorb gold cyanide in competition with the activated carbon. Since the native carbon is ground with the ore it is much smaller than the activated carbon. Any competition between the two carbons may produce a loss of gold from the pregnant leach liquor to the process tailings. This phenomenon is called “preg robbing”. Goldstrike ores come from the Carlin trend, which is known for the occurrence of native carbon (Adams & Burger, 1998; Schmitz, Duyvesteyn, Johnson, Enloe & McMullen, 2001; Tretbar, 2004)."

Jan 1, 2012

By H. B. Merlin

"The past demands for energy and the contributions by the major sources are shown for the world and regions, and for Canada. Three forecasts of future demand are presented. By the year 2000, the world will be consuming energy at a rate of 670-700 x 1015 Btu/year. Canada's rate is estimated at 20 x 1015 Btu/year. Electricity will increase its portion of energy from 7.5 per cent to 15 per cent, and more than 40 per cent of the primary energy w1ll. be required to generate 1t. World, regional and Canad1an forecasts are g1ven for total electricity generated and for electricity generated in nuclear stations. The integral world requirement for energy by the year 2000 will be over 12 x 10 18 Btu. Current recoverable fossil and hydro reserves are about 18 x 1018 Btu. The total reserves are estimated to be seven times greater.World production of electricity in nuclear stations by the year 2000 will be almost three times the electricity produced in the world today. The amount of fuel consumed in generating this electricity will depend upon the types and mix of reactors installed. The heavy water reactors, alone or in conjunction with fast breeders and liquid fuel reactors, are the most efficient users of uranium and thorium resources. The heavy water reactors are also the most efficient producers of plutonium which will be required as fuel for fast breeders."

Jan 1, 1969

By T. Kerr, C. Mattich, J. Wilson

"In refractory gold concentrates, gold is occluded in sulphide minerals preventing efficient cyanide leaching. Hence, roasting is used to oxidize sulphur and organic carbon, the latter being necessary to minimize recovery loss through the preg-robbing effect. In 2009, Outotec commissioned the circulating fluidized bed roaster at Syama gold mine in Mali. Since 2013 Resolute and Outotec have been implementing improvements to the roaster performance with the capacity increasing from 8000 t/month in 2013 to above 13,000 t/month in 2016, while achieving a residual sulphide sulphur and organic carbon contents of below 0.1 wt.% and 0.4 wt.%, respectively. Thus a gold recovery in the CIL of above 90% is attained. In 2016, Outotec audited the Syama roaster. The analysis resulted in the Low Carbon Roaster (LCR) upgrade concept which (i) allows re-processing of calcine dust from the spray cooler and ESP after pelletization and (ii) allows the roasting of a further fine-organic carbon rich feed, i.e. de-slime circuit tailings. The LCR upgrade aims to reduce organic carbon to <0.2 wt.% and increase roaster-leaching gold recovery by >3%. Project development included extensive testwork. The LCR process is expected to become operational during FY 2019.INTRODUCTION Double refractory sulphide ores exhibit the characteristics of gold locked within pyrite grains, in the presence of preg-robbing natural (organic) carbon. Hence, to achieve high recovery during subsequent processing steps, i.e. cyanide leaching, oxidation of sulphide sulphur is required, producing a porous calcine by way of a roasting step. This allows for the gold contained within the pyrite grains to be accessible during cyanide leaching. Furthermore, it is necessary to oxidize the organic carbon. Oxidizing the organic carbon is essential as gold recovery loss occurs as a result of gold-cyanide complexes being adsorbed on organic carbon, this phenomenon is termed as preg-robbing (Miller et al., 2016). The gold absorbed on the organic carbon is lost, reporting to the tailings stream. Hence, the aforementioned oxidation of sulphide sulphur and organic carbon is the process goal. Nonetheless, the latter must occur at a controlled temperature which is concentrate/ ore specific, since the pores of the produced calcine should not sinter, as this makes the gold contained in the calcine less accessible during leaching, leading to gold recovery loss. The tight temperature control requirement is a decisive factor in the choice of a Circulating Fluidized Bed (CFB) as the roasting reactor, due to the excellent mixing characteristics of the CFB which results in temperature homogeneity of (+/-10°C). Roasting of double refractory ores, as described above, can be included in the flowsheet after comminution and grinding, a process termed as whole ore roasting, or by including a flotation circuit termed as concentrate roasting. Roasting the flotation concentrate results in less solid flow, increased sulphide sulphur grade and organic carbon content resulting in a higher heating value and higher gold content. A typical composition of the Syama ore and concentrate is given in Table 1. Ore average values presented correspond to the period 2015, while concentrate values are typical for the flotation performance throughout the period 2012–2015."

Jan 1, 2017

By W. K. Gummer

"THE LOCATION of Canada's present aluminum industry is determined by availability of hydroelectric power, and ready access to ocean transport facilities. The chief raw material for the production of the metal is imported by ship over several thousand miles of water. In times of freedom of shipping and uncontested movement this provides the industry with its cheapest method of operation. However, during the early part of the last decade the general conditions of ocean and rail transportation were such that interest in the treatment of materials other than bauxite was greatly stimulated. This was the case not only in Canada, of course, but in most other countries.Canada has no deposits of bauxite and much research was carried out on other aluminous materials, chiefly silicates, in an effort to develop more or less economic and feasible methods of treatment. In the United States, this research was considerably more extensive. Some projects were early shown to be of little or no value, whereas others, including the widely publicized lime-sinter and soda-lime-sinter methods, became important. In North America, however, apart from the application of the sinter method to the hitherto waste-product (red mud) of the normal Bayer plant operation, none of these processes contributed appreciably to the production of aluminum during the war. In certain European countries, on the other hand, largely because of their situation with regard to bauxite deposits, they had a more general application, and Germany, for example, produced alumina from clay, ashes, and slag by at least four methods."

Jan 1, 1952

By N. H. J. Freire, D. Majuste

In this paper, the effects of some organic compounds on the current efficiency, cell voltage and specific energy consumption during nickel electrowinning, and on the deposit features (morphology, crystallographic orientation and nanohardness) were described. The organics tested here (extractant, diluent, flocculant, lubricating oil and acid mist suppressant) are currently used in industrial plants. The results indicated that only the flocculant and acid mist suppressant exhibit relevant negative impacts on the current efficiency and energy consumption. The current efficiency dropped from 93.6 % (organic-free solutions) to 86.0 % and to 92.8% in electrolytes containing 100 mg.L-1 of acid mist suppressant and flocculant, respectively. At this concentration, their addition to the electrolyte led to increases of the specific energy consumption in the order of 18 % (acid mist supressant) and 2 % (flocculant). Cyclic voltammetry showed that Ni nucleation occurs at more negative potentials at 50 and 100 mg.L-1 of these organics in the electrolyte, thus indicating an inhibition of the deposition process. The deposit quality decreased at the higher concentration of all organics, when more hydrogen pitting was observed. The acid mist suppressant caused delamination of the Ni deposit at 50 and 100 mg.L-1. The addition of 100 mg.L-1 of flocculant and acid mist suppressant to the electrolyte increased the nanohardness of the deposit around 31 and 72%, respectively. The increase in Ni deposit hardness may lead to a decrease in the material ductility, thereby affecting the stripping and cutting of Ni sheets. Our findings may be helpful since strong adverse effect of some organics that may be present in the electrolyte were identified, thus the industry can control and optimize the organic´s dosage in the corresponding operations.

Jan 1, 2016

By Z. Yang, M. J. Collins, N. E. Tuffrey, R. J. Kalanchey, I. M. Masters

The high elevation of China Western Mining Company (WMC)&apos; s Ganhe refinery, and the high iron content of concentrates produced by the WMC mines, were key factors in the selection of pressure leaching by WMC for their new zinc refinery. This paper describes the results of pressure leaching test work conducted by Sherritt in Fort Saskatchewan with a sample of WMC concentrate from Qinghai Province in China. Results from batch pressure leach tests and a four-day pilot plant campaign are reported. The pilot plant campaign included continuous operation of a two-stage pressure leach circuit, as well as neutralization and iron removal steps, resulting in the production of iron-free zinc sulphate solution. Greater than 98% zinc extraction was achieved in pressure leaching, while producing solution containing about 9 g/L H2SO4 and 2 g/L Fe. Following neutralization and iron removal, the solution contained about 170 g/L Zn and less than 10 mg/L Fe. Overall recovery of sulphur in the zinc concentrate feed to elemental sulphur byproduct was about 85%, while 75 to 80% of the indium in the feed was recoverable from the neutralization residue. The test results highlighted the technical and economic advantages offered by the Sherritt Zinc Pressure Leach Process and provided the required data for the engineering design.

Jan 1, 2008