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By Louis Frost

"Dominion No. 17 Colliery, of the Dominion Coal Company, Limited, is located in the district of New Victoria, N.S., at the entrance to Sydney harbour.This Colliery was opened in 1882 to work a submarine area of the Harbour seam (see Figure 1). It was closed in 1921 and the mine, which has a make of water of approximately 250 gallons per minute, was allowed to fill.No. 18 Colliery, situated almost a mile to the east, was opened in 1938 to work the Phalen seam in this area with the intention, later, of driving a cross-measure tunnel to mine the section of the Harbour seam lying between No. 17 Colliery and the Princess Colliery of the Nova Scotia Steel and Coal Company, Limited.In 1945 it became necessary to open this area in the Harbour seam and a cross-measure tunnel was driven from the existing workings of No. 18 Colliery in the Phalen seam, which underlies the Harbour seam at a depth of 500 feet.The tunnel was started in 1946 and completed in 1948. The cost of opening this section, which contained only 6 1/2 million tons of coal, made imperative the recovery of all the available coal and precluded the maintenance of the large barriers that had been left in No. 17 Colliery for impounding the water, especially as the maintenance of these barriers would have meant the loss of 885,000 tons of coal, or 12.3 per cent of the whole tonnage available. Therefore, a study was made to determine the best means to dewater the 250 million gallons of water lying in the old No. 17 Colliery."

Jan 1, 1952

By W. D. Fogwill, P. J. Clarke

"The Dawn Lake uranium deposits are located 340 km north of La Ronge, Saskatchewan, in the Athabasca Basin between the Midwest Lake and Rabbit Lake deposits. Four zones of uranium mineralization, called the ""11, 14, 11A and 11B Zones,"" lie within the Athabasca Sandstone, at the sub-Athabasca unconformity and in the basement.At Dawn Lake, approximately 100 metres of Helikian Athabasca Group clastic sediments overlie Aphebian Wollaston Group pelitic and calcareous metasediments and pegmatites. Uranium with some nickel, cobalt and copper, occurs near the sheared stratigraphic contact between calc-silicate gneiss and graphitic, pyritic pelite. The mineralization lies in an area of low magnetic susceptibility which is thought to represent a rock sequence lying stratigraphically high within the Wollaston Group. There is no obvious vertical displacement of the unconformity by faulting, despite considerable brecciation, shearing and slickensides seen in the basement rocks. This suggests horizontal displacement on steeply dipping wrench faults as the main tectonic control along the 11, 11A and 11B trend.Below the Athabasca unconformity, the Wollaston Group rocks are altered to fine-grained mixtures of clays, chlorite and silica commonly called regolith. Along the mineralized trend post-Athabasca fracturing and (or) compaction have occurred through this clay-rich alteration zone, causing the steeply-dipping primary foliation to become contorted. This ""crenulated"" horizon can reach depths of 35 metres below the unconformity and is thickest along fault zones in the calc-silicate rocks. The ""crenulite"" is a distinctive unit which at Dawn Lake is commonly found above pods of ore located deep below the unconformity.Much of the mineralization in the 11A and 11B Zones occurs above, beside and below the thickest part of the crenulated zone, although the crenulated rock itself contains negligible amounts of carbonate, pyrite and uranium. Intense vuggy alteration and collapse breccias are found in calc-silicate rocks deeper and to the west of the 11A and 11B mineralization. There are at least two ages of uranium deposition in the basement zones, shown by small bright cubes of ""pitchblende /"" overgrown and replaced by duller botryoidal ""pitchblende II. ""Sooty pitchblende and yellow secondary minerals are the result of still younger reworking.The geological setting of mineralization, along the contact between carbonate-rich calc-silicate rock and pyritic pelite, suggests that the uranium was concentrated at a pH/Eh boundary located between deeply weathered, carbonate-rich and sulphide-rich basement rocks."

Jan 1, 1986

By D. P. Goodall

THE development of the oil and gas resources of Western Canada is not, as many suppose, a new industry. For more than half a century an intensive search for these valuable products of nature extended from near the western edge of the Precambrian Shield to the Pacific coast, and from the International boundary north to the Arctic circle. The chief centre of interest to the oil prospector has, however, always lain in that region lying east of the first range of the Rocky mountains and confined largely within the boundaries of the Province of Alberta. Although there are many geological problems yet to be worked out in this Province, the oil-well driller has helped in no small way in determining sub-surface conditions and distribution of rock formations. The chief geological conditions as they affect the drilling of wells are generally re-cognized, and for this purpose the Province may be partitioned into three main divisions: first, the disturbed belt or foothills region extending along the eastern edge of the Rocky mountains; second, the Alberta geosyncline, a broad trough lying to the east of and parallel to the disturbed belt and from which the formations rise eastward to level off and form, third, the plains ? ? region, extending over the rest of the Province. A relatively small area in the northeastern part of the Province is underlain with Precambrian rocks and may be excluded from this classification, as it is of no interest to the oil prospector. The foothills, or disturbed belt, has presented the greatest difficulty to drilling, though it has produced the largest yield of oil within the Province to date. Within the foothills belt, the rock formations consist largely of hard shales interspersed with layers of abrasive sandstones, which wear out drilling bits at an alarming rate. The strata, in most flaces, dip steeply and are cut by numerous thrust faults. Although some o the faults have great displacements, their presence may easily be overlooked or the extent of the fault misinterpreted. Many a prospect well has been located on what appeared to be a suitable geological structure only to find, after drilling through a normal succession of rocks for 4,000 feet or more, that the drill had passed through a major fault plane to a younger formation than that in which drilling was started. Only a repetition of formations already drilled could be expected at greater depths.

Jan 1, 1942

By V. Feldman, I. Holl, J. Zampini

"The Renard Mine, 100% owned by Stornoway Diamonds, is located approximately 250 km north of the Cree community of Mistissini and 350 km north of Chibougamau in the James Bay region of north-central Québec. The project benefits from a large and growing resource, good mining conditions, strong social acceptance, a modest environmental footprint, and the development of direct-to-mine road infrastructure. Construction began on July 10, 2014; following the completion of a 946 million CAD project financing transaction. Now completed, the mine is the first diamond mine in Québec, and one of only six in Canada, employing approximately 500 people. First ore was delivered to the plant approximately 5 months ahead of schedule on July 15, 2016. Commercial production was declared on January 1, 2017. In general, the project ramp up has been characteristic of a type 1 McNulty curve. One of the challenges during production ramp-up was a redesign of processed kimberlite dewatering (replacing the dewatering centrifuge with two stages of hydrocyclones and a dewatering screen). A processing opportunity captured by Stornoway was the design and installation of an ore sorting facility which rejected free waste rock from the valuable host rock; kimberlite. Through tackling both challenges and opportunities, Stornoway has realised and is now exceeding their original design tonnage.PROJECT DESCRIPTION Stornoway Diamond Corporation (Stornoway) was established in 2003 resulting from to a plan of arrangement between Northern Empire Minerals Ltd. and Stornoway Ventures. In 2011, Stornoway acquired 100% interest of the Renard Mine. The construction of the Renard Mine began in 2014 and achieved full production in 2017 [1, 2]."

Jan 1, 2019

By W. A. Jankola, M. T. Martin

"The world's first zinc pressure leaching plant at Cominco's Trail operations started production in 1981. Sullivan zinc concentrate is leached at the rate of 190 tpd in a four-compartment autoclave at elevated temperatures and oxygen pressures to produce a zinc sulphate solution and elemental sulphur. Zinc extraction exceeds 98% and sulphide to elemental sulphur conversion exceeds 95%.The sulphur is recovered from the discharged slurry in the underflow of a hydrocyclone, and is upgraded as a flotation concentrate. The concentrate is dewatered, melted and filtered to produce a polished sulphur product of better than 99% purity. An alternative sulphur recovery process employs an unique sulphur separation method that recovers over 90% of the sulphur in the molten state. The remaining sulphur is recovered by flotation following flash discharge of the slurry. The product slurry containing the zinc sulphate solution and the iron-lead residue joins the existing roast-leach zinc plant for purification and zinc electrowinning.IntroductionIn 1981, Cominco Ltd. commissioned the world's first commercial zinc pressure leaching plant at their Trail operations in British Columbia. As part of a $700 million modernization and expansion program for lead and zinc started in 1977, the company installed the first o f two autoclave trains.Prior to pressure leaching, zinc production was closely tied to acid and fertilizer production. Sulphur dioxide produced from roasting the concentrates had to be converted to sulphuric acid. Thus, any expansion of zinc operations with the roast-leach technology would have required extensive modifications to the acid and fertilizer plants as well as to the roasters. Zinc pressure leaching, on the other hand, offered a one-step dissolution of zinc from the concentrates with high extraction, and production of elemental sulphur. The associated dust and sulphur dioxide generated in the roasting process are both eliminated from the working environment of the pressure leach facility. The flexibility allowed by producing elemental sulphur, and the opportunity to break the sulphuric acid link for about 25 per cent of the targeted 272,000 tonnes per year zinc production was very appealing. The process was successfully demonstrated at a pilot plant in 1977(1-6)."

Jan 1, 1985

By M. P. Davies

"Risk, the product of probability and consequence, is an integral part of mining. Whether evaluating exploration priorities, determining property acquisition potential, reviewing the components of an operating mine or assessing environmental/closure issues, the concept of minimizing risk is central to economic and technically appropriate decision making.Until recently, risk evaluations have tended toward a strongly mathematical basis. With this previous trend, it was essential to establish precise probability density functions to all assessed components or issues where often little information was available. The combined effect of the seemingly complex analyses with corresponding insufficient data often resulted in either a poorly executed risk evaluation or no evaluation whatsoever; either result not acceptable for optimal decision making. This paper presents a simple and practical procedure to carry out risk assessments for the mining industry. Although simplistic in nature, the power and usefulness of the technique is immense. The basis for the procedure involves combining deterministic assessments (often “gut feel”) with appropriate probabilistic descriptors. The resulting procedure, termed Potential Problem Analyses, or PPA, can be used anywhere an evaluation of risk will assist in optimizing technical and/or economic decisions. As will be shown, a key element of the PPA procedure is the multi-disciplinary input the framework allows which makes the method ideal for a teamwork approach to decision making."

Jan 1, 1997

By Yan Yang

The Jinfeng gold mine is one of the three gold mines that Eldorado Gold has in China and it is the second largest gold mine in China. The mine is located in a relatively remote and mountainous area in the southwestern Guizhou province. The orebody is similar to the Carlin type deposit in Nevada. The mill throughput was designed to treat 3,600 tones per day. The ore comes from open pit mining and underground mining, and is fed to one-stage jaw crushing. The crushed ore is stockpiled, reclaimed and then fed to the SABC grinding circuit. After classification with hydrocylones, the ore is floated, and the resultant concentrate is oxidized biologically in a process known as BIOX®. The oxidized concentrate is then washed in a CCD circuit and finally leached with cyanide in a CIL circuit for gold extraction. Jinfeng produces about 180,000 oz of gold per year. This paper introduces operations and modifications of SABC circuit over the past three years, and then describes some technical characteristic of the SAG mill and other circuits in the processing plant. Major modifications and improvements on the SABC circuit are described in the paper, including: 1. Impacts of grinding ball and mill liner with respect to material selection, quality, hardness, manufacturing methods, and interactions between mill liner and grinding ball. 2. Effect of milling operation parameters on milling efficiency. 3. Impacts of SAG mill scats and modifications of grate size to improve mill throughput. 4. Design and construction of a pebble crushing system, and recycle the crushed scats to the SAG mill to improve mill throughput. With the above-mentioned modifications, 20% increase over the design in mill throughput has been realized over the past three years, and operating cost has been significantly reduced. However, some issues still remain, and thus process modifications and technical innovations are still needed.

Jan 1, 2012

By O. Lundhede

Today, systems and machinery usually are designed to meet only one specific customer?s requirements. One reason for this is that underground automation and smart functions are often developed tightly together with a customer. This is natural, since risk and cost can be shared between the customer and the supplier. Nevertheless, when the automation product develops and the market increase this will cause problems: The highly specialized products will not fulfill the next customer?s demands. In order to cope with this problem, Atlas Copco works towards a common platform. Instead of designing solutions for specific customers, we will lift the abstraction and focus on standardized modules. These modules, or function blocks, can then be combined in a large variety of configurations. The benefits of combining modules into products are, for example: increased flexibility when options are available for many machines; easier commissioning and maintenance since less different spare parts and tools are needed; and easier operation since the user interfaces have a similar look and feel. This paper will present the ongoing work towards standardized modules. We will discuss how our Rig Control System (RCS) allows for modular design at Atlas Copco. RCS has number of standardized modules that are used in different surface and underground mining and tunneling equipment. These modules are also used for optional products such as, drilling, radio-remote control, and telematics systems.

Aug 1, 2013

By P. R. A. Andrews, R. K. Collings

"There are more than 300 occurrences of fluorite in Canada. Deposits of economic significance, however, are confined to Newfoundland and Nova Scotia in eastern Canada, Ontario in central Canada, and British Columbia in western Canada. Fluorite has been mined and processed intermittently in Ontario and Newfoundland until November 1990, when Canada's only producer Minworth Ltd., a U.K. based company, with a mine and concentrator near St. Lawrence on the Burin Peninsula, Newfoundland, closed its operation.CANMET has processed ore samples from each of the major mineralized areas, and thirty-one studies were conducted between 1920and 1970. A summary of the important aspects of the various testwork studies is presented. The production of acid-grade fluorite was possible by flotation, and ceramic-grade, by flotation and gravity concentration methods. Gravity concentration methods included heavy media separation, jigging and tabling. Flotation was by direct and reverse techniques; associated minerals, quartz, calcite, barite, etc. were depressed by a variety of depressants. The function of the major depressants is discussed briefly. The various uses offluorite which include hydrofluoric acid, chlorofluorocarbons, aluminum production, petroleum alkylation, fluxing and ceramic applications etc. are discussed briefly."

Jan 1, 1993

The principles and utility of in-situ coal gasification are discussed, and a first field test conducted by the Alberta Research Council in 1976 near Forestburg, Alberta, is described. The test was carried out in a 12-ft subbituminous coal seam under 60 feet of cover. Within this seam, a 30 by 60-foot block , containing approximately 650 tons of coal, was delineated by four injection/production holes which were oriented to take advantage of the natural fracture system in the coal. Linkage between holes was established by reverse combustion and gasification was accomplished by injecting air into the ignited coal. No steam was injected but operating pressures were adjusted to utilize formation waters for partial carbon -steam gasification. The coal gasification runs lasted six weeks and gasified an estimated 900 tons of coal ,' during sustained periods of gasification, a fuel gas with heating values of between 110 and 150 Btu/scf was obtained. Plans are now being developed for excavating the test site and inspecting the subsurface cavities created by gasification.

Jan 1, 1977

By J. Shahabpour

"Breccias with angular and rounded clasts of a late-mineralization, ""barren"" hornblende porphyry dike set within a comminuted matrix consisting of rock fragments and quartz, cemented by quartz and K-feldspar of hydrothermal origin is observed in diamond drill cores from the Sar Cheshmeh porphyry copper deposit. Studies of age relationship between vein types, phyllic-altered clasts and the breccia groundmass suggest that the brecciation is a late event. The breccia clasts record evidence of hydrothermal reaction between the clasts and fluids responsible for the brecciation.Formation of bornite, in the breccia clasts of the originally barren hornblende porphyry dike, and in the breccia matrix, along with the scarcity of bornite in the Sar Cheshmeh deposit itself suggest involvement of fluids which are later and of different composition from the fluids responsible for the known mineralization at Sar Cheshmeh. These later fluids may be related to a later plutonic event and suggest the possibility of a later, and concealed deposit."

Jan 1, 1994

By E. V. Manlapig, U. Erol, V. Ross, K. Tshimanga

Lonmin RoM ball mills are treating two types of feed ore produced by conventional mining and mechanised mining methods. It was reported that reduction in mill throughput was observed when treating the mechanised mining ore. Detailed grinding surveys were conducted for troubleshooting. Ore samples were collected for breakage characterisation using a JKRBT based on different particle density components. XRD analysis was conducted to investigate the association of minerals with density components. The plant surveys and the breakage characterisation tests all suggested that the two mining methods did not significantly affect either the ore breakage properties or the RoM mill performance. Instead, the mill discharge open area exerted a remarkable influence on mill throughput. The RoM ball mill operated at Lonmin K4 Concentrator has been proven to be a versatile mill that performed stably with variations in feed size distribution and feed ore changes by different mining techniques. The reasons are elucidated by the multi-component breakage characterisation and the plant surveys data.

Jan 1, 2012

By J. A. Allan

"The history of the development and application of controlled recirculation systems in U.K. collieries is traced and the theory behind such systems briefly examined. Specific applications for dealing with dust and dust/heat problems in headings, for which practical experience is currently available, are described. Consideration is given to the special features which these systems introduce in the underground situation and to the essential safeguards which are required for their safe use.IntroductionRecirculation of air is a commonly used technique in genera l ventilation and air conditioning practice, but has always been regarded with some suspicion for mining applications. This is perfectly understandable in view o f the hazardous conditions which can occur with dangerous forms of recirculation in mines. However, certain controlled recirculation techniques can offer advantages, particularly in the field s of dust and climate control in headings, provided that they are designed, Installed an d managed with full comprehension o f all aspects of the system and always bearing in mind that from the point of view of serious firedamp ignition risk, headings are potentially the most hazardous places in coal mines.BackgroundProbably the first recorded use of deliberate recirculation in British collieries was reported by Lawton in 1933. This researcher described trials, undertaken under the auspices of a national committee on ""The Control of Atmospheric Conditions in Hot and Deep Mines"", involving attempts to increase the velocity, and thereby the cooling power on hot faces, by means of simple recirculation systems using fans and ducts delivering recirculated air in the opposite direction to the normal face airflow. No significant cooling advantage was obtained and there is no subsequent record of this work being continued. During the discussion on this paper, there was considerable disbelief that fire damp percentages had not increased significantly when air was recirculated, but apparently no attempt was made to establish why this should be. It is of interest to note that J. Ivon Graham, one of the contributors, recommended that recirculation should be tried in stone headings for the control o f dust, as he believed that ""there may be scope for recirculation and filtration of the air under certain circumstances in such headings"". This idea was not developed for another forty years."

Jan 1, 1983

By A. Ignatieff

"THE WORLD'S coal resources represent the largest component of non-renewable energy resources. Coal is now regaining Its position following a temporary decline, particularly in North America during a period of about a quarter of a century. This period provided the opportunity to improve both surface and underground mechanization, thereby increasing the productivity and improving conditions for humans in the mines. Similarly, in preparation, improved cleaning of coal from various impurities including sulphur was achieved, to meet the more demanding requirements for coking coal. Progress was also made in combustion, particularly related to the reduction of pollution. Canada participated in most of these developments, despite the country's strong commitment of the use of hydrocarbons during this period. _Bearing in mind the vastness of this land (3.85 million sq. miles) by comparison with countries like U.S.A., U.S.S.R., and China, Canada's coal resources estimated to date are not large and they are scattered. The original evaluation of 1913 estimated the ""reserves"" from seams over one foot in thickness and a limiting depth of 4,000 ft at 1.2 trillion metric tons. D:. ~.R. MacKay, in his evaluation for the 1946 Royal Commission on the coal industry, known as the Carroll Commission, reduced the ""reserves"" to 99 billion short tons. The increased knowledge now available would indicate that the 1913 estimated was too liberal and the 1946 estimate too conservative but both were closer to a resource than to a reserve designation. Some adjustments of Dr. MacKay's estimates were made in 1970 by B.A. Latour of the Geological Survey of Canada and L.P. Chrismas of Energy, Mines and Resources Canada (EMR). In the last decade the Alberta Energy Resources Conservation Board has developed its own methods of evaluating coal resources and reserves. A methodical approach of exploration and evaluation was carried out by Saskatchewan jointly with the federal government of the lignite resources of Southern Saskatchewan. A similar joint program is in progress in Nova Scotia. Meanwhile, the industry itself carried on an extensive exploration program on the outcrops of promising projects in the Inner Foothills belt of Alberta and British Columbia in preparation for surface mining on a very large scale, with some development of hydraulic mines. All these activities have been reflected in the increase of the country's resources and reserves, which now fortunately are separately defined. In 1979 EMR issued Report E.R. 79/9(1>; the data were developed in 1978 and provided to the World Energy Conference Organization<2>. In 1980 the World Coal Study (Wocol), an international group that included Canada carried out a study which updated the W.E.C. data, indicating some reduction of the 1978 figures; quantities were reported in million metric tons of coal equivalent (C.E.)*(Jl."

Jan 1, 1985

By S. R. L. Harding

"Introduction0N MAY 2th, 1953, Socony Seaboard Pembina No. 1 well, located 70 miles west-southwest of Edmonton, was completed as a producer of high-gravity oil from the Cretaceous Cardinm sand. This event is possibly the most significant in the development of the oil industry in Western Canada since the Devonian discovery at Leduc in 1947. The result of the Pembina discovery and the follow-up drilling has been a tremendous increase in interest in the Cardium formation.Descriptions of the Cardium formation, as it occurs in the 'Central Foothills' and in the 'Southern British Columbia Foothills' have been presented by R. E. Folinsbee (9)-and C. R. Stelck (21), respectively. The purpose of this paper is to discuss the more regional aspects of the subject.The name Cardium was first used .as a stratigraphic term in 1863. Dr. James Hector ( l2), geologist attached to Captain John Palliser's exploratory expedition, gave the name 'Cardium to the whole section of marine Cretaceous beds exposed along the Bow river west of Calgary."

Jan 1, 1955

"The Val d&apos;Or Division now comprises the Lucien C. Beliveau Mine and Concentrator (formerly the Pascalis, described below) and the Chimo Mine. Cambior acquired an initial 50% interest in the Chimo Mine in May 1989 and the remaining 50% in April 1990. Cambior&apos;s share of 1989 production was 2121 ounces; the company expects to net 23 750 ounces from Chimo in 1990. Pascalis MineUPDATERenamed the Lucien C. Beliveau Mine at its official inauguration in September 1989, the mine is exceeding forecasts, producing over 11 500 ounces of gold in the first half of 1990. Cambior expects 1990 production to total 34 000 ounces.IntroductionThe Pascalis Mine is located 16 miles east o f Val d&apos;Or, Quebec, and is accessible by a three mile gravel road off highway 117 (Fig. I).The property is wholly owned by Cambior.The Pascalis gold deposit consists o f a sub-vertical diorite dyke 1000 ft long by 30 ft wide containing quartz and tourmaline veins with inclusions of pyrite and native gold . Three vein systems ca n be seen in the deposit , the most important being tensile veins oriented at a right angle to the direction of the dyke and inclined at 40 degrees. These overlapping veins vary in thickness from 4 in. to 40 in. and occur at intervals of six to ten ft. The deposit is, therefore, very difficult to evaluate; a complete evaluation would require drifts over the whole width of the dyke combined with relatively short drill holes (Fig . 2)."

Jan 1, 1990

By J. A. du Plessis, C. Dorfling

Selenium, tellurium and other precious metals (OPMs, namely Rh, Ru and Ir) dissolve in the final leaching stage of base metal refineries. Se and Te are typically removed from the copper sulphate leach solution by precipitation with sulphurous acid. Recovery of dissolved OPMs is desirable because it will reduce OPM inventory and losses. Thiourea is an effective OPM precipitation reagent, but yields insufficient Te removal. Copper is known to enhance Te precipitation when using sulphurous acid as precipitation reagent. The primary objective of this project was to evaluate whether simultaneous precipitation of Se, Te and OPMs using thiourea with metallic copper as precipitation reagents is possible. Batch precipitation tests were performed to evaluate the effect of temperature (50 – 70°C), thiourea addition (160 – 430% excess) and copper addition (2 – 8 g/L) on Se, Te and OPM precipitation. Increasing the temperature from 50°C to 70°C resulted in an average increase of 55.6 percentage points for Se precipitation and 13.5 – 23.5 percentage points for OPM precipitation. The copper addition did not have a significant impact on the precipitation behaviour. Increasing the thiourea addition increased the precipitation of Se and Te, especially when the copper addition was low; Rh and Ru precipitation also increased with up to 10 and 12 percentage points, respectively. Despite these observations, the precipitation of Se was significantly faster when no thiourea was added. It is not currently clear why thiourea appears to inhibit the Se precipitation by reaction with metallic copper. In general, Te precipitation was low (less than 30%) at the conditions investigated. Simultaneous precipitation of Se, Te and OPMs at temperatures below 80°C does not appear to be a viable option; a multiple stage operation for sequential removal of Se and Te with copper followed by OPM precipitation with thiourea would be required.

Jan 1, 2016

By K. E. Waters, N. Brodusch, R. Gauvin, H. Demers

"Rare earth elements are becoming increasingly in demand, due to their prevalence in both renewable energy devices and high-end electronics. The characterization of the composition, morphology and volume fraction of the various phases that have valuable rare earths in the ores are needed to find the optimal industrial process to extract the ores containing the rare earths. Rare earth-bearing minerals contain many elements with the M-and L-lines overlap, requiring a high degree of resolution, pushing the boundaries of scanning electron microscopy quantitative analysis. Enhanced microscopy at a high spatial resolution with improved x-ray quantitative analysis enables the accurate determination of the distribution of the desired rare earths in various mineral phases. INTRODUCTIONRare earth elements are becoming increasingly in demand, due to their prevalence in both renewable energy devices and high-end electronics. From batteries (lanthanum and cerium), to magnets (dysprosium and neodymium) and lighting (yttrium), the rare earth elements are crucial to the advancement of technology, and to energy saving devices (Crow, 2011). The goal of this project is to characterize the composition, morphology and volume fraction of the various phases that have valuable rare earths in the ores in order to estimate the economical VALUES (of the ores and to find the optimal industrial process to extract the ores containing the rare earths. High spatial resolution imaging and x-ray microanalysis are needed to reach this goal. In this work, the results obtained with a cold-field-emission scanning electron microscope (FE-SEM) and a silicon drift detector (SDD) energy dispersive spectrometry (EDS) detector at low accelerating voltage are compared to experimental conditions typically used with electron probe microanalysis (EPMA) instrument.With this improvement, a detailed scientific analysis of the composition of these, and other, ores will become possible with a SEM/EDS system. This will help to better understand how such ores were formed, hence assisting in finding them, and to better understand how to process them in preparation for high end industrial applications, namely through mineral processing."

Jan 1, 2012

By G. Kipouros, M. Dadvand, A. Dadvand

"A novel methodology was developed to obtain a 3D porous layer with a high aspect ratio of porosity on a titanium electrode. The porous structure allowed more active material such as hydrous ruthenium oxide to be accommodated during the fabrication of the supercapacitor, resulting in an exceptionally high capacitance per surface area. The electrode demonstrated a remarkably high capacitance of 4,800 mF/cm2. The porous layer was composed of functionalized nanoparticles of TiO2 organized in a perfect 3D hexagonal close-packed array that resulted in a highly porous 3D structure. The layer was used as a template to electrolessly deposit a thin layer of silver prior to the electrodeposition of active material. KEYWORDS Capacitance, Porous, Ruthenium, Silver, Supercapacitor, Titanium RÉSUMÉ Une méthodologie innovante a été mise au point afin d’obtenir une couche poreuse tridimensionnelle (3D) affichant un rapport d’aspect élevé en termes de porosité sur une électrode en titane. La structure poreuse permet d’utiliser une matière plus active telle que l’oxyde de ruthénium hydraté durant la fabrication du supercondensateur, ce qui se traduit par une capacité exceptionnellement élevée par surface active. L’électrode affichait une capacité remarquablement élevée de 4 800 mF/cm2. La couche poreuse était composée de nanoparticules fonctionnalisées de dioxyde de titane (TiO2) organisées dans un arrangement regroupé parfaitement hexagonal en 3D, qui a engendré une structure en 3D hautement poreuse. Cette couche a servi de modèle pour le dépôt autocatalytique d’une fine couche d’argent avant l’électrodéposition de la matière active. MOTS CLÉS argent, capacité, poreux, ruthénium, supercondensateur, titaneINTRODUCTION There is a growing demand for integrating compact energy storage elements into electronic circuits due to the miniaturization of electronic circuits, sensors, and actuators, and the increasing importance of portable and wear-able devices incorporating more advanced electronic technologies that operate in controlled or uncontrolled environments to gather, process, store, and communicate information (Deng, Ji, Chen, & Banks, 2011; Beidaghi & Wang, 2012; Chen, Ramachandran, Mani, & Saraswathi, 2014). The manufacturing of compact energy storage elements needs to be compatible with the electronic circuit microfabrication processes. Recently, interest in integrating miniaturized supercapacitors into electronic circuits has increased due to their high charge–discharge rate and long operating life; however, ultra-high power miniaturized supercapacitors suffer from low energy density, hence requiring significant enhancement in their energy density for various applications (Deng et al., 2011; Beidaghi & Wang, 2012; Chen et al., 2014)."

Jan 1, 2019

By V. C. Wittchen, T. R. Yu, J. E. Croxall

"The consolidated rockfill at Kidd Creek Mines is a weakly cemented, minus 15 cm aggregate which posed problems for conventional drill/blast drifting methods. Consequently, lateral access to mineable ore adjacent to backfilled areas was gained by drifting around the fill in shattered rock.In mid-1987, Kidd Creek Mines began to investigate means of mechanically excavating drifts in backfill . The results of this investigation led to a trial program using a Dosco MK-2A Roadheader to excavate the required drifts in backfill.The roadheader was tested at Kidd Creek Mines from July to November 1988, in 28-735 X /C to be used as the top access for drilling and blasting 32-74/ ST. During this period, the roadheader excavated 54 m of a 4.3 m by 3. 7 m arched drift in backfill. Cutting rates over the period averaged 0.8 m/cutting hour as projected with a daily high of 2.0 m/cutting hour.Wood-lagged 2-piece steel arches on 1.2 m centres were chosen as ground support for the trial. Shotcrete will be tested in a roadheader drive for its potential to improve productivity by replacing the steel arches.The trial program included evaluations of point-attack picks, two sizes of cutter motor, 20 MPa (3000 psi) water-assisted cutting, cuttings-removal systems, and environmental control devices."

Jan 1, 1990