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By S. Averill, B. Schreiner, V. Sopuck

The La Ronge. Kisseynew, Glennie Lake and Flin Flon domains. the main focu for gold exploration in the southeast part of the Saskatchewan Shield, were subject to continental glacial ice advances from the northeast during the Quaternary. Based on forty-four auger hole along with surficial mapping, the general Quaternary stratigraphy in this area is observed to be composed of a lower till unit , an overlying stratified unit of glaciofluvial sand and gravel and/or a glaciolacustrine silt-clay unit. an upper till. and an upper tratified unit. The lower till is commonly found throughout the geological domains except where it has been eroded in glaciofluvial or fluvial channels. Glacial Lake Agassiz fo rmerly covered most of these prospective domains. The lacustrine deposits associated with the lake impede surficial geochemical surveys including soil. lake sediment. and biogeochemical surveys. The approximate extent of clay cover can be predicted from beach elevations. For instance. in the Waddy Lake area. clay i not known to occur above about 1,400 feet (425 m) elevation. Exploration techniques are hampered by clay in at least one third of the volcanic belt. Thi s influence is indicated by the fact that nearly all gold prospect found to date are located above 1,400 feet (425 m) while the area of clay cover is vi rtually unexplored. The upper till i related to a minor ice readvance. This till is the medium often sampled during soil surveys in the area . lts value as a geochemical ampling medium is dependent on the extent of erosional contact with bedrock highs on the lower till. Those areas which are relatively free of lacustrine and fluvial deposits are those where surface geochemical methods work best. In the Waddy Lake volcanic belt approximately 25-50% of the area may be suitable for surficial surveys. The area of the Star Lake prospect occurs above the 1,500 foot (460 m) elevation and was not covered by Lake Agas iz. The effectivene of till sampling as a surface sampling medium was tested in those areas above the clay level. Till orientat ion surveys were carried out at the Star Lake property and the Tower Lake prospect (Waddy Lake area) within the La Ronge Domain . Gold grain counts and analy es of heavy mineral concent rate from 7 kg surface ti ll samples were used to delineate dispersion trains down-ice from mineralization. In addition, the clay fraction and a 30 g (-80 mesh) subsample from the same till sample, were analyzed for gold . In the Star Lake area, ice direction is subparallel to the strike of several narrow northeast trending auriferous structures. arrow dispersion trains down-ice from known

Jan 1, 1986

By Philippe Caudal

This paper presents a case study in which a slope failure was observed on the west wall of the LAB Chrysotile mine in the vicinity of the main ramp in January 2010. Airborne LiDAR results were used to evaluate slope geometry before and after the failure occurred. Back analysis of the failure was performed to assess rock mass properties at the slope scale using various numerical techniques: limit equilibrium, finite elements and fracture networks. The various approaches correlated well with field observations.

Aug 1, 2013

By F. Baczek, S. S. Rocks, D. Chaiko, C. Eyzaguirre, S. Asihene, T. Walters

The majority of efforts to improve primary copper sulfide leaching have focused on solution chemistry, temperature, O2 pressure, ultra-fine grinding, the use of catalysts, etc. Historically, very few studies have focused on the solid/solution interface. A new, patent pending approach to catalyzed, copper sulfide leaching has been discovered by FLSmidth that enables manipulation of the 2-D semi-conductor properties of chalcopyrite surfaces to the benefit of higher electrochemical reactivity. Copper dissolution rates are then further accelerated by incorporating a Stirred Media Reactor (SMRt) into the process. By using minute amounts of Cu2+ to "pre-activate" chalcopyrite, leach times have been reduced from >20 hours with incomplete Cu dissolution to <2 hours with 98+% Cu dissolution at 80°C. The pre-activation process takes only minutes to complete at temperatures of 80°C or less. The total atmospheric leaching process, incorporating the pre-activation and Stirred Media Reactor is compatible with existing SX/EW processes. Results of batch leach testing are presented and possible mechanisms are discussed.

Jan 1, 2015

By D. M. Muir

The mineralogy of residues formed during the pressure acid leaching of arid region nickel laterite ore varies according to the salinity of the process water, alkali cation additives and the overall acid loading. In fresh water, hematite is the main iron-bearing leach residue component, together with amorphous silica and hydronium or sodium alunite/jarosite [(H3O,Na)(Fe,Al)3(SO4)2(OH)6]. As the process water salinity increases, or as NH4+ or K salts are added, alunite/jarosite is the kinetically favoured iron-bearing phase accompanied by an increase in acid consumption. The alunite/jarosite appears as two XRD distinct phases with different Fe:Al molar ratios. In weakly saline water, iron-rich alunite/jarosite slowly transforms to hematite and an aluminium-rich alunite/jarosite together with the release of acid. The addition of potassium salts forms a more stable alunite/jarosite whilst the addition of ammonium salts leads to greater transformation of alunite/jarosite at 250°C. Weakly saline process water gives enhanced nickel recoveries, whilst strongly saline process water gives lower nickel recoveries but higher soluble iron because of chloro-complexation. SEM and microprobe analysis shows very little nickel is associated with the alunite/jarosite and hematite phases. Nickel losses to the residues are attributed to adsorption on amorphous silica and to a lesser extent on alunite/jarosite.

Jan 1, 2006

By John B. Riddell

"AN EXCELLENT review of the status of applied geochemistry was given by Warren (1959) at last year's General Meeting of the C.I.M. The purpose of this paper is to present recent developments and trends. Several important books were announced during 1958: Ginzburg, I. I. Principles of geo-chemical prospecting. (In process of translation from the Russian by V. Sokoloff).Vinogradov, A. P. The geochemistry of rare and zvidely scattered chemical elements in soils. Consultants Bureau, N.Y. Korzhinskii, D. S. Physicochemical basis of the analysis of the paragenesis of minerals. Consultants Bureau, N.Y.In addition to these translations Mason's Geochemistry' has been revised, and Hawkes and Webb (personal communication) are publishing a book on geochemical exploration. A Symposium on Geochemistry was head in Paris in July, 1957, in conjunction with the XVIth International Congress of Pure and Al-lied Geochemistry. The abstracts of the papers presented at this Symposium were published in Geochimica et Cosmocl1imica Acta, 1958, Vol. 14, pp. 150-167."

Jan 1, 1960

By L. Tong, D. Robinson

"The stirred milling of nickel laterites offers possibilities for improving liberation and selective size reduction of soft nickel-bearing minerals in laterites. Batch grinding tests were performed in a netzsch™ lME4 stirred mill on siliceous goethitic, goethitic, and saprolitic nickel laterites. Tests on the -2,000 µm sample displayed the effects of selective comminution. The -38 µm product of grinding the -2,000/+38 µm feed confirmed the effects of selective grinding and nickel upgrading. Size classification followed by stirred milling is recommended for nickel upgrading. The energy requirement in the stirred milling was also investigated.RÉSUMÉ le broyage par billes de latérites comportant du nickel offre des possibilités d’amélioration de la libération et de la réduction sélective de la taille des minéraux nickélifères tendres dans les latérites. Des essais de broyage en vrac ont été effectués dans un broyeur à billes netzschMD lME4 sur des latérites nickélifères à goethite siliceuse, à goethite et saprolitiques. Des essais sur l’échantillon -2000 µm présentaient des effets d’une comminution sélective. le produit -38 µm de l’alimentation -2000/+38 µm confirme les effets d’un broyage sélectif et du rehaussement de la teneur en nickel. Pour améliorer la teneur en nickel, il est recommandé de classifier le minerai en fonction de sa granulométrie, puis d’effectuer un broyage à billes. l’énergie requise pour le broyage à billes a aussi été étudié."

Jan 1, 2015

By B. van Beek, T. Goff, P. Gebski, P. Szyplinski, W. L. Ying

"Monitoring the refractory lining integrity is essential to assure the safety of the operators and to determine the remaining campaign life of a furnace. Early detection of refractory lining degradation is essential to avoid sudden furnace failures and prevent unscheduled shutdowns. In the mid-1990s a stress wave propagation technique was developed and since then it has been utilized by Hatch Non-Destructive Testing (NDT) Group to evaluate furnace linings. For the last 17 years the AU-E technique evolved in terms of hardware, software and signal acquisition and interpretation. Most importantly, based on more than a decade of commercial applications, an extensive database of various failure modes, refractory deterioration trends and material properties has been created. This knowledge base is an integral part of AU-E which progressed from a NDT technique towards a comprehensive approach for furnace condition monitoring. All of the improvements introduced over the last several years have greatly improved the accuracy of the measurements. The data analysis process has also become more time efficient making the critical results available to the furnace operators in a more timely manner. Today the AU-E technology is used on a variety of process vessels in non-ferrous, glass, chemical and iron and steel industries.In this paper we are reviewing the available techniques for furnace refractory lining measurement and discussing the pros and cons of each method. The need for continuous improvement and development of new techniques for refractory monitoring is also emphasized. Finally, we are presenting a number of case studies and comparisons between the physical verifications and the AU-E measurements."

Jan 1, 2015

ABSTRACT The inevitable uncertainty in modelling spatial variables decreases as more data become available. This reduction depends on the properties of the variable being modelled. Spatially continuous variables show less uncertainty for a given spacing than erratic variables. A geostatistical simulation based approach is developed to quantify the relationship between uncertainty and data spacing. Reference realizations are sampled to condition additional realizations and quantify uncertainty. The procedure is automated, making it straightforward to consider sensitivity and different geological domains. A case study of the relationship between uncertainty and data spacing for net oil sands thickness data from northern Alberta is presented. _ KEYWORDS Simulation, Sampling,

Jan 1, 2013

By M. Krasowska

Dynamics of collision and kinetics of the bubble attachment to hydrophobic solid plates (Teflon) of different surface roughness were investigated. The experiments were carried out in such a way that probability of the collision and probability that the detachment will not occur were equal always 100%. Thus, it was possible to determine effect of the surface roughness on the bubble attachment (three phase contact formation, TPC) only. A high-speed camera (1182 Hz) was used to record the velocity variations, bouncing and time of attachment of the bubble colliding with Teflon plates having different surface roughness (5 different plates). Roughness of the plate surfaces was modified in a mechanical way using different abrasive papers. It was found that the roughness had a crucial influence on the time-scale of the TPC formation and attachment of the bubble colliding with the Teflon plates. Despite high hydrophobicity of all plates (contact angles 1100 -115º) it was observed that at the smoothest surfaces (called "Teflon I" and "Teflon II" and having surface roughness below 1 um) there was no attachment during the bubble first collisions. Prior to the attachment four or more "approach?bouncing" cycles of the colliding bubble were observed there and simultaneously the bubble shape varied rapidly within time intervals below 0.85 ms. Time of contact of the colliding bubble with the Teflon plates was very short; 2-3 ms. These results indicate that during that short time of the collision the liquid layer separating the colliding bubble and the solid surface did not reach a critical thickness of its rupture.

Jan 1, 2006

By John Dasher

The analyses reported on in this paper indicate that there are hydrometallurgical routes from sulphide concentrates to copper that are potentially competitive with smelters which are not permitted to emit sulphur oxides. The various hydrometallurgical processes, and their economics, are discussed.

Jan 1, 1973

By H. L. Snyder

This paper outlines the approach to the underground construction work involved in the Churchill Falls Power Project. It is the first in a series of papers which CIM Bulletin plans to publish as the different 11hases of this large-scale operation evolve.

Jan 1, 1968

By W. Tse, D. Wong

Dense medium separation (DMS) is one of several preconcentration methods used for early waste rejection from run of mine ores at relatively coarse particle sizes prior to additional milling and beneficiation. DMS has been used extensively in the coal, diamond and iron ore industries but lab scale and pilot test work has demonstrated successful separation and upgrading of other minerals such as lead, zinc, copper and lithium based ores using DMS. This paper reviews historical dense media systems, results from the pilot scale Condor DMS system as well as associated laboratory heavy liquid separation (HLS) test work.

Jan 1, 2014

By J. Finch, Wei Zhang

In this paper we describe the synthesis of a new homologous series of linear Polyglycol-based frothers that consist of Ethylene Oxide (EO) and hydroxyl as hydrophilic groups and Propylene Oxide (PO) and alkyl chains as hydrophobic groups. The synthesized frothers were of two types: Alkyl-Ethoxy-Propoxylate (abbrev. CnEOlPOm) and Alkyl-Propoxy-Ethoxylate (CnPOmEOl) giving: (a) different number of groups and chain length, and (b) different locations of the groups. The identities were confirmed by proton nuclear magnetic resonance (NMR) spectroscopy and total organic carbon (TOC) analysis. The characterization of the products was carried out in a bubble column. At steady state, bubble size, gas holdup and water overflow rate were measured as a function of frother concentration. The results indicate that increasing number of PO groups led to significant decrease in bubble size, and increase in gas holdup and water overflow rate. Increasing the alkyl chain length, gave similar but less pronounced trends. There was no impact of increasing the number of EO groups on bubble size but there was an in increase in gas holdup and water overflow rate. Changing the location of the PO and EO group had a significant effect on all three parameters.

Jan 1, 2015

By X. -G. Chen, K. Liu

Nowadays, great interests are rising on aluminum alloys for the applications at elevated temperature, driven by the automotive and aerospace industries requiring high strength, light weight and low cost engineering materials. As one of the most promising candidates, Al-Mn-Mg 3004 alloys is found to possess considerably high mechanical properties and creep resistance at elevated temperature resulted from the precipitation of a large number of thermally stable dispersoids during heat treatment. In present work, the effect of Fe contents on the evolution of microstructure as well as high temperature properties of Al-Mn-Mg 3004 alloys has been investigated. Results show that the dominant intermetallic changes from a-Al(MnFe)Si at 0.1 wt.% Fe to Al6(MnFe) at both 0.3 wt. % and 0.6 wt. % Fe. In the Fe range of 0.1 to 0.6 wt.% studied, a significant improvement on mechanical properties at elevated temperature has been observed due to the precipitation of dispersoids, and the best combination of compression strength and creep resistance at 300°C is obtained in the alloy with an intermediate Fe content (0.3 wt.%) with finest size and highest volume fraction of a-Al(MnFe)Si dispersoids. The superior properties obtained at 300°C makes 3004 alloys more promising for high temperature applications. The relationship between the Fe content and the precipitation of stable dispersoids as well as the materials properties has been discussed.

Jan 1, 2015

By Roger J. Berdusco

Kaiser Resources Ltd. owns and operates a 5-million-tonper- year open-pit and hydraulic coal mine near Sparwood in southeastern British Columbia. Since 1969, Kaiser has maintained a field-scale reclamation program dedicated to the reclamation of disturbances associated with past and present mining and exploration activities . Since that time, over 1400 acres have been treated using modified forestry and agricultural techniques with encouraging results.

Jan 1, 1978

By Mike Dry, Rod Dry

If humanity is truly serious about reducing emissions of carbon dioxide into the atmosphere, today’s power plants burning fossil fuels will have to be replaced by power plants that do not emit CO₂. Unless carbon capture/sequestration becomes practical, the new power plants will be hydroelectric, wind, solar or nuclear installations. Hydroelectricity requires the appropriate geography. Solar installations can only deliver power as and when sunshine is available, and wind installations when the wind blows. Therefore, power from these sources will be intermittent, but the demand for electricity does not follow the patterns of sun and wind. That will require large-scale electricity storage and/or load following by the remaining power suppliers, increasingly so as the use of fossil fuelled power generation declines. Modern nuclear power plants are designed for demand following. However, operating at lower than design output has a negative impact on the economics of nuclear power plants because the overall cost of the electricity they generate is dominated by capital cost. Primary (blast furnace) iron smelting is responsible for a significant part of global CO₂ emissions because the reagent used is carbon. Were it available in sufficient quantity (and at a low enough cost), hydrogen could replace carbon in the manufacture of raw direct reduced iron (DRI), using technology such as modified HYL (Tenova Hyl, 2018) or Midrex (Ravenscroft, 2017). This paper examines a scenario in which, instead of demand following, nuclear power stations are operated at their design capacities and surplus power is used to generate hydrogen in off-peak periods. This hydrogen is then used to replace carbon in the manufacture of raw steel.

Jan 1, 2020

By A. W. Jolliffe

AEROPROSPECTING may be defined as the application of the air view to the search for mineral deposits. The term is suggested as a preferable alternative to either aerial prospecting (which may be confused with areal prospecting) or air prospecting. The air view may be obtained by visual observation from an aircraft or by examination of air photographs; each has its particular advantages and disadvantages. Aeroprospecting should be regarded only as an aid to, and not as a substitute for, accepted prospecting methods ( l ). The Precambrian region north of Great Slave lake consists of two well defined physiographic units, a feature first noted by J. T. Wilson (2). The boundary between these lies close to the north shore of the east arm of the lake and extends northwesterly near Spencer, Beniah, Carp, and Ghost lakes (Figure 1). South and west of this line, exposed bed-rock makes up the greater part of the land area; eskers are very rare, and overburden is largely limited to rock-walled valleys and depressions. North and east of the line, outcrops are rare or absent, eskers are abundant, and most of the surface consists of drumlin-like drift hills, elongated parallel to the direction of ice movement (Figure 2). Where this boundary passes through the area shown in Figure 1, it lies near the 1,200-foot contour and may mark the maximum extent of the lake or sea arm present in this vicinity toward the end of the Pleistocene period. For convenience, the first area may be called the &apos;bed-rock belt&apos; and the other the &apos;drift belt&apos;.

Jan 1, 1945

By A. Zrimsek, G. Vingas, R. Wolke

IN 1952, prompted by the great demand of the Canadian drilling and foundry industries for sodium bentonite, the Geological Department of Magnet Cove Barium Corporation, Limited began an extensive search for bentonite deposits throughout western Canada. Their efforts were rewarded in 1958, when substantial deposits of high quality material were found approximately 100 miles southeast of Edmonton, Alberta. The bentonite material, a part of the Edmonton formation in the Upper Cretaceous, is located approximately nine miles south of the town of Rosalind. The land where the bentonite lies has in places .been eroded by stream and glacial action to form a wide gully, convenient for strip mining methods (see Figure 1). The bentonite bed is almost flat-lying, dipping to the southwest at approximately 12 feet per mile. The main bed is 8 to. 10 feet thick and is covered with 15 to 25 feet of overburden. Before stripping, the area is drilled and sampled to evaluate the quantity and quality of the bentonite.

Jan 1, 1962

By Aidan Giblett, Michael McGlynn, Peter Radziszewski

"On the basis that 99% of the energy input into a mill is converted into heat, it is possible to estimate the amount of energy captured in the slurry, the amount that is lost to the environment as well as the possible means to reduce such losses. As a result it becomes possible to estimate the potential amount of energy that can be captured by technologies such as thermoelectric generators or even Sterling engines. Furthermore, it has been suggested that the energy recovery potential dry grinding circuit could be as high as twice that of wet grinding circuits.In this paper, the energy recovery potential of dry grinding will be explored by examining the case of the Newmont Carlin mine dry grinding circuit. The paper will open with a review of the energy recovery potential of a few wet grinding applications followed by a description of the dry grinding circuit and a definition of the control volume around that circuit. A thermodynamic model will be used to estimate the circuit discharge temperature and an estimate of any losses as well as provide an estimate of the potential impact of different means to reduce energy losses. The paper will close with a discussion of the assumptions used in model development."

Jan 1, 2016

By Manjeet Chowdhry, Qingxia Liu, Phillip Choi, Zhenghe Xu

Computational chemistry methods, such as density functional theory (DFT), are powerful tools to quantify reagent-mineral interactions encountered in sulphide mineral flotation. A quantitative relationship between theoretically calculated parameters based on chemical structure of collectors and their reactivity with different metals/minerals can provide valuable insights for design and development of more powerful and tailor-made reagents offering enhanced metal/mineral selectivity. DFT calculations at B3LYP/6-311++G(3df,3pd) level were employed to elucidate the reactivity of neutral sulphide collector reagents, including thionocarbamates (TC), thioureas (TU), xanthogen-formates (XF), dialkyldithiocarbamates (DTC) and dialkyltrithiocarbonates (TTC) with different heavy metal ions (Cu2+, Zn2+ and Pb2+) in solution. The extent of delocalization of lone pair electrons of heteroatoms (attached directly to C in C=S) over C=S group was found to be the dominant factor in determining the collector’s reactivity. Order of reactivity was established as: TU > TC > XF > DTC > TTC. All the collectors showed superior affinity towards copper followed by lead. Unidentate binding was observed through sulphur atom except for xanthogen-formate for which bidentate binding mode was observed. Effect of nature of substituent groups at N and/or O atom on reactivity of thionocarbamate and thiourea was also investigated. The results obtained through DFT calculations are consistent with the experimental data reported in literature.

Jan 1, 2015