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By J. Budac, R. Kofluk, D. Belton, M. Sjogren

A series of tests were performed to determine the flammability limits of mixtures of oxygen, ammonia, steam and nitrogen, over a solution, in a sealed autoclave. The partial pressures of ammonia and oxygen in the vapour space were varied by adjusting the character of the solution and by adjusting the oxygen concentration in the oxidant gas respectively. The data shows that flammable conditions can be minimized by controlling the operating temperature, reducing the ammonia content in the solution, increasing the concentrations of Ni, Cu and Zn in solution and keeping the % oxygen in the gas phase less than 15.5. Observations were also made that suggest that the presence of an aerosol in the vapour space may hinder ignition.

Jan 1, 2004

By J. C. Marchand, M. A. Berube

"L'objectif principal recherché lors du broyage d 'un minerai est de libérer adéquatement ses valeurs utiles en vue de leur concentration ultérieure. La pratique courante consiste à tenter d'obtenir un produit de broyage d'une granulométrie constante. Malheureusement, les propriétés texturales des minéraux utiles varient naturellement dans un gisement et une telle stratégie n'entraine pas toujours pour ces minéraux un degré de libération constant. Pour un rendement optimal du procédé de concentration, cette variable très importante doit donc être périodiquement vérifiée.Jusqu'à maintenant, la plupart des études de libération des minerais se font en examinant des sections polies de particules du minerai broyé. Le GRAAIM a récemment assemblé un système modulaire d'analyse d'images qui servira en grande partie à des mesures automatiques du degré de libération des minéraux. Le système s'avère relativement peu coûteux comparativement à la plupart des analyseurs de texture conventionnels si l'on considère que plusieurs de ses composantes, par exemple le miniordinateur, sont utilisées à une foule d'autres applications, et il permet de plus une grande souplesse d'utilisation puisque l'on a qu'à construire des algorithmes de mesure et de calcul en fonction de l'objectif recherché. Des programmes particuliers permettant des études automatiques de libération sur des sections polies de particules ont ainsi été élaborés. Ils permettent également des mesures de teneurs et de distributions granulométriques apparentes des particules. Des résultats obtenus dans le cas de minerais de fer sont brièvement présentés afin d'illustrer la technique."

Jan 1, 1983

By T. S. Heah, S. T. Bishop

"The Lorraine property is located in the northern Intermontane Belt, north-central British Columbia. The property is underlain by intrusive rocks of the Duckling Creek Syenite Complex, an Early Jurassic, alkaline phase of the Late Triassic-Early Cretaceous Hogem Batholith. Two significant zones of copper-gold mineralization have been explored to date; the Main zone (historical Upper and Lower deposits) and the recently discovered Extension zone. A combined geological resource was estimated in 1975 for the Main zone deposits at 10 million tonnes averaging 0.7% Cu, and from 0.1 g/t Au to 0.34 g/t Au. The Extension zone, still at an exploration stage, is estimated to be considerably smaller than the Main zone.Copper-gold mineralization at Lorraine Mountain exhibits characteristics suggestive of both magmatic and hydrothermal origins, and may be related to orthomagmatic-hydrothermal fluid flow contemporaneous with magmatism and development of migmatitic fabrics. A depth greater than the depth of formation of classical porphyries may explain many of the variations displayed by mineralization at Lorraine. These characteristics distinguish Lorraine from other members of the alkalic suite of porphyry Cu-Au deposits in the Canadian Cordillera.IntroductionThe Lorraine prospect is located in the Omineca Mountains, at the headwaters of Duckling Creek, 56 km northwest of Germansen Landing (Fig. 1). The property is centred at latitude 55°55'N, longitude l25°26'W on NTS mapsheet 93N/14W. The area is typified by mountains of moderate relief, with elevations ranging from 1150 m in the valleys to peaks of 2000 m. Valleys are U-shaped and blanketed by glacial till which give way to steep, talus covered slopes and sharp ridges. Outcrop is generally limited to elevations above 1600 m (Fig. 2)."

Jan 1, 1995

By G. W. Sparkes

The use of CR-39 plastic polymer as a solid state nuclear track detector in the textural analysis of radioactive minerals in geological samples was first described by I.R Basham in 1981. CR-39 autoradiographs provide a detailed, high-resolution image of the in situ distribution of the radioactive minerals within geological samples on both the macroscopic and microscopic scales. This technique is an inexpensive and effective means of obtaining detailed textural information that provides insight into the style of mineralization, its relationship to primary and secondary structures in the host rock, and its association with particular geological features or mineral phases. Although this technique does not provide any information on the identity of the minerals responsible for the radioactivity, the resultant autoradiographs can be used to select regions for further detailed analysis such as petrography, microprobe analysis, or SEM imaging. This paper summarizes the procedure and outlines the appropriate time and materials required for both the exposure and etching of the CR-39 with respect to the intensity of the radioactivity emitted by the geological samples.

Jan 1, 2013

By P. D. R. Maltby

This paper describes the background and markets for calcium carbonate and silica sand in Canada, as well as the results of recent test work carried out at the Ontario Research Foundation. Tests on sericite, tremolite, vermiculite, barite and graphite are also mentioned.

Jan 1, 1979

"An innovative concept is proposed whereby the operating power for haul trucks in certain areas of an underground mine are reduced in order to lower ventilation costs. Airflow that must be provided for diesel-powered equipment in most jurisdictions are regulated based on engine peak power capability and engine emissions, both of which can be lowered by artificially reducing the capacity of the engine through the engine control unit. Advances in asset tracking and ventilation on demand enable this methodology and this study demonstrates that it could represent significant value for mine operators. An examination of haul truck duty cycle indicates that de-rating of engine operating power based on the truck’s location in the mine can enable a step change in ventilation rates, often with no material impact on working conditions. Methods for implementation and estimate of cost savings will be defined.INTRODUCTION Ventilation of underground workings remains a significant operating cost burden for modern mine operators. In particular, ventilation rates for underground diesel mining equipment are often defined by local regulatory bodies and are assumed to present minimal opportunity for optimization or savings, at least until battery propulsion systems can be adopted. Commonly, the quantity of air flow required is defined by the peak rated engine output power of diesel equipment. For example, Ontario Regulation 854 SS 183.1 (3) states that “The flow of air must be at least 0.06 cubic metres per second for each kilowatt of power of the diesel-powered equipment operating in the workplace”. Jurisdictions that define air flow using the prescribed CANMET or MSHA ratings use peak engine emissions to calculate air flow required for dilution ventilation. These approaches are similar in that the maximum power capability of a vehicle’s engine is used to define the ventilation rate in all areas where it travels, regardless of what power output is actually used in any of those areas. Examination of the duty cycle of a typical underground haul truck identifies a large variance in the power output of the vehicle depending on its location in the mine and the activities undertaken at these locations. For example, travel on a mining sub-level requires a fraction of the truck’s peak power due to the minimal grade and significantly reduced travel speed. So if we can reliably reduce the peak engine power capacity and engine emissions in areas where peak power is not required, we can logically cut the ventilation rates for those areas."

Jan 1, 2017

By H S. Ellis

Flow studies have been conducted on nickel-water suspensions in a 1in.-diam., 42-ft.-long transparent lab-oratory pipeline at concentrations of up to 25 per cent, by volume, and slurry velocities of up to 15 ft/sec. The average size of the nickel powder was approximately 150 mesh (106J.L). Three flow regime were noted. At the highest velocities, i.e., above 10 ft/;sec., where the concentration distribution through the vertical diameter was most uniform, pressure gradients could be correlated with the Durand-Condolios equation (7,8). An intermediate region, i.e., from 7 ft/sec. to10 ft/sec., could be distinguished, the lower velocity limit being that at which nickel particles began to deposit. This region was also marked by decreasing pressure gradients, for a given concentration, as the velocity was reduced. The upper velocity limit in this region was also uniquely defined in that the friction factor for any nickel concentration was the same as that for water. In the third regime, below about 7 ft/sec

Jan 1, 1963

By Bunting S. Crocker

This paper reviews the trends in the past two years in autogenous grinding throughout the world. It covers rock grinding in South Africa, Sweden, Canada, the United States, Finland and Germany. To properly orient the discussion on this subject, the paper attempts to define and classify the scope of autogenous comminution. As this is a relatively new subject, there is often considerable confusion regarding the various practices, which sometimes differ widely. By clarifying the types and forms, we hope to help clear up this con-fusion. Autogenous grinding is being carried out, throughout the world, either in mills grinding in water or solution or in dry mills using air classification to remove the finished material. The wet grinding, particularly, can be divided into: (1) (2) (3) Primary autogenous grinding, or "run-of-mine" grinding. Secondary autogenous grinding or semi-autogenous grinding or rock pebble grinding. Combination processes. -This covers plants in which pebbles made in the primary mill are re-moved and used as grinding media for fine grinding in secondary mills.

Jan 1, 1963

By W. G. Schultz

"Sylvite's potash mine, which produces 8,000 tons of ore per day, probably ranks as one of the most highly mechanized and automated mining operations in the world. Employing, on a normal 10-hour production shift, one supervisor and a crew of seven operators, Sylvite is able to mine at an average rate in excess of 600 tons per hour. The ore is produced by two Marietta miners weighing 258 tons, the largest and heaviest pieces of equipment ever taken underground. The ore produced by these two Marietta miners is conveyed to the shaft area, cycled through a 15,000-ton storage system and hoisted to surface completely automatically. The operation of all equipment in the mine can be monitored and controlled from a central control panel located underground. Because Sylvite's mine is a new operation with equipment of a new design, the full potential of the operation has not yet been realized. The ultimate capability is clearly evident from the success Sylvite has had over the past year as the average mining capability has risen from 100 tons per hour to 600 tons per hour."

Jan 1, 1973

By Jack Craft

Local Environment Atmospheric conditions (or lack thereof) Drilling fluids are impractical Cuttings removal is a major concern Heat dissipation is a major concern Some tried-and-true mechanisms need air to function properly Gravity Low gravity means low downforce Microgravity means even less downforce Regolith Local dust may be highly abrasive Packaging for Spaceflight System mass is highly constrained The drill must fit within the spacecraft?s launch envelope Power is constrained

May 1, 2013

By N. Campbell, W. T. Orvine

The metalliferous deposits of British Columbia are largely confined to that portion of the Cordilleran province lying west of the Rocky Mountain trench. Massive sulphides in the coastal area carry important copper •values together with lead and zinc and are composed mainly of pyrite which replaces schists or shear zones. The massive sulphide ore of the interior, on the other hand, contains lead and zinc with little copper. Pyrrhotite rather than pyrite is... the dominant metallic and deposition took place through selective replacement of sedimentary beds.

Jan 1, 1960

By F. Chachula, A. Molinaro

"Sulphide mineral flotation operations continuously strive for a balance between mineralogy, mineral liberation, circuit conditions and reagent solutions to maximize the production rate and recovery of payable metals. The Taseko Gibraltar copper – molybdenum mill operations underwent an extensive project focusing on the fundamentals to identify the effects of process conditions and mineral liberation to improve the bulk circuit copper – molybdenum recovery efficiencies in the bulk flotation circuits. This discussion will provide process data that demonstrates; 1) fundamental relationship between mineral liberation to recovery and grade, 2) flotation circuit condition testing and optimization, 3) reagent combinations resulting in efficient/economical mineral recovery, and 4) the development of a xanthate free reagent solution. The data presented and discussed will also touch on flotation parameters including pH, retention time, kinetics and the effect on bulk circuit recovery performance.INTRODUCTION Taseko's is the owner (75%) and operator of the Gibraltar copper-molybdenum mine, located in south-central British Columbia, the second largest open pit copper mine in Canada and the largest employer in the Cariboo region. Taseko restarted Gibraltar in 2004. From 2006 until 2012, the company invested ~$700 million to expand and modernize the operation which was originally scheduled for demolition when the company acquired it in 1999. In the spring of 2011, construction commenced for Gibraltar Development Plan 3 (GDP3). GDP3 included the construction of a standalone 30,000 ton per day concentrator, built adjacent to the existing 55,000 ton per day facility. The new design capacity of Gibraltar was designed to be 85,000 tons per day. An integral part of the project was a new molybdenum recovery facility. In addition to the new concentrator, the mining fleet was upgraded with a new mining shovel, production drill and ten haul trucks (Taseko, May 2015). In May of 2015, the Company completed an updated mine plan for Gibraltar featuring a 50% decrease in strip ratio. This new mine plan was a result of a detailed, six-month engineering study and forms the basis of an updated NI 43-101 compliant reserve (Taseko Announces Improved Economics At Its Gibraltar Copper Mine, 2015). The new mine plan took into account lower milling costs as a result of the modernized processing facilities (Taseko, May 2015)."

Jan 1, 2018

By N Robb

This paper gives an account of the laboratory testing, plant testing and final inclusion of the two-stage sulphuric acid leaching process in the Milliken mill. Operational results for September, 1962, are presented, showing a uranium extraction of 95.5 per cent, with a saving of some 16 lbs. of 100 per cent H~S04 and some 9 lbs. of lime per ton milled. Methods for effecting further improvements in the process are indicated. HISTORY P RIOR to the incorporation of two-stage leaching, the process for the treatment of uranium ores at Milliken consisted of a single-stage sulphuric acid leach, followed by a solution recovery step involving washing in thickeners and two-stage filtration. The thickener overflow solution was subsequently concentrated and purified by ion exchange, and the uranium was recovered, by two-stage precipitation, as ammonium diuranate. Figure I illustrates this flowsheet. For satisfactory extraction of uranium from the. Milliken ore, a high residual acidity, of the order of 40 grams per litre of free acid in the discharge solution, must be

Jan 1, 1963

By R. A. Ford

The paper outlines: methods used for the determination of wear metals in motor and transmission oils; contaminents in motor, transmission and crusher lubricating oils; and viscosity determinations. Case histories and costs are presented to illustrate the value of an oil analysis program. Introduction NORANDA MINES LIMITED (BELL COPPER DIVISION) is located on the shores of Babine Lake, approximately 450 miles north of Vancouver, British Columbia. Access to the mine is by road from Topley, B.C., about 40 miles away. When a preventive maintenance analysis program was first considered, it was obvious that if samples were to be sent out for analysis, results would not be available for at least a week, due to the distance from any commercial laboratory. The assay laboratory was asked to investigate the possibility of determining wear metals on site. A limited program was started soon after production commenced, and this has now grown to include all large mobile equipment as well as crushers and grinding mills. The laboratory also now determines viscosity, fuel dilution, dirt and abrasives, glycol and water. All these results are ready within two days. This paper will outline the methods used, data interpretation, several case histories and the benefits from such a program.

Jan 1, 1977

By Bruce Macdonald

Operational monitoring of slope stability can be achieved by space based InSAR monitoring platforms. Natural and man-made rock slopes are monitored using a novel stack-based InSAR method that exploits both persistent point scatterers (PS) as well as coherent distributed scatterers (DS) such as areas of pavement and sparsely vegetated surfaces. The new method, Homogenous Distributed Scatterer (HDS)-InSAR identifies InSAR targets by using adaptive multilooking of statistically homogenous pixel neighbourhoods combined with thresholding the differential temporal coherence of each target candidate with respect to its surroundings. HDS-InSAR preserves PS and therefore forms a direct generalization to our proven DualScale-PSI method. The density of HDS exceeds that of PS by more than an order of magnitude often providing essentially continuous coverage over urban and industrial landscapes featuring a mix of infrastructure with mostly bare soils or rock surfaces. The improved coverage enables better definition of surface motion and underlying geology, which will lead to superior interpretation of the geophysical mechanisms causing the surface deformation, e.g. through improved integration with 3D deformation modeling. We illustrate the performance of our new HDS-InSAR method compared to DualScale-PSI using displacement results from Vancouver, Canada; Bingham mine, USA; and the Palabora mine, South Africa.

Jun 1, 2012

By L. F. Haven

"The desirable shovel speed-torque curves are described, along with the characteristics of the more important electrical components used to approximate these curves. A particular shovel regulator system combining these components is discussed in detail and some of the advantages and disadvantages of the system are given.INTRODUCTIONIN 1959, STATIC CONTROL was for the first time successfully applied, installed and operated on a mining machine in North America. Since that time, a great deal has been learned about this control by the people maintaining these machines as well as by the de-signers.In 1961, the first SCR (Silicon Controlled Rectifier) or thyristor control system was installed on an excavator. This control differed from the earlier static control in that thyristor excitors supplied the generator fields directly. The development of thyristors of a sufficient rating to supply amounts of phase-controlled power to the generator fields eliminated the bulky Mag. Amp. -Rectifier combination previously used."

Jan 1, 1969

By Robert F. Shurtz

This paper discusses and compares methods of statistical analysis of the information relating to the evaluation of an asbestos deposit. From a study of 10-ft. lengths of drill core, the separate effects of visual evaluation errors were determined, as well as the deviations between evaluators and the deviations produced by a slight displacement in the center lines of the check drill holes. The importance of careful statistical analysis of such information is stressed.

Jan 1, 1966

By P. Dauphin

"CANMET’s Mining and Mineral Sciences Laboratories have developed the Canadian Mining Technology Network (CMT-Net), a website to provide industry with up to date information on technologies in several areas. This paper gives background on the Mineral and Metal Processing sector, describes the steps leading to the development of the websites strategy and gives a tour of CMT-Net. IntroductionThe government of Canada is developing a strategy aimed at fostering the development of value-added activities in the area of mineral and metal processing (MMP). Natural Resources Canada (NRCan) and Industry Canada will partner in delivering on this strategy. Instrumental in defining the main thrusts of the value-added strategy was a series of consultations held across Canada with representatives of companies and organizations active in the sector. The objective of the consultations was to identify barriers to the development of activities which add value in the sector, as well as point to positive factors.Following the consultations, a discussion paper was produced, “From Mineral Resources to Manufactured Products: Towards a Value- Added Mineral and Metal Strategy for Canada” (Natural Resources Canada, 1998). The paper reviews the sector’s structure and main statistical information, lists some of the positive factors and barriers to value-added activities and defines a new partnership between industry and government that will lead to more valueadded activities. The main objective of the paper is to serve as a discussion document between stakeholders during the development of the strategy."

Jan 1, 1999

By T. Patching

"MINING operations at the Star Key Mine provided an example of a small-scale prairie-type coal mine that employed several interesting procedures and achieved good productivity with low capital expenditures. The mine was located about 11 miles north of the city of Edmonton, on the north side of the Sturgeon River valley. It opened in 1945 and operated until 1979. Output in the winters reached about 500 tons a day in the late 1940s, but in the spring and summer periods activity was usually limited to only servicing and development work. In the later years of the mine's life sales fell to less than 100 tons per day. Most of its output was bought for domestic use in furnaces and stoves so production of large sizes was desired. A modest market for stoker coal did exist for a time. Screenings (-5 / 8 in.) were sold to the city's power plant until it converted to natural gas and were also used for thawing frozen ground for work on pipelines. These markets were comparatively small and the small sizes did not command as high a price as did the larger sizes. However the extension of natural gas services to rural markets cut into the domestic heating market and finally led to closure of the mine. The coal was strong when freshly mined, but because of its high inherent moisture content, about 25%, it did not store well on surface but tended to disintegrate. It was of subbituminous Crank with a heating value of about 8000 Btu per pound and burned with a clean flame. The seam mined was in the Edmonton Formation, of Upper Cretaceous age, at a depth of 60 to 80 ft below the surface. The seam in the mine area was about 11 feet in thickness but thinned gradually to the north and south and split to the west (1). It was approximately horizontal but gentle rolls in the floor of several feet in height necessitated brushing in places to produce suitable haulage grades. The floor material was of bone and clay, overlying a thin layer of coal. Above the seam there were only a few feet of mudstones and weak sandy shales while the remainder of the overburden was clay and unconsolidated glacial till and surface soil. Because of the soft floor and weak roof material the miners usually left about a foot of coal in the floor to provide a firm working surface and about a foot of coal above the rooms and two feet of coal above the entries to provide a competent roof."

Jan 1, 1985

By J. B. McKay

It is the purpose of this paper to present an initial report on the construction and operation of the Fluo-Solid roaster at the property of Campbell Red Lake Mines, Ltd., Balmertown, Ontario. The roaster prepares for subsequent cyanidation the bulk flotation concentrate obtained from four hundred tons per day of gold ore. The mill flow-sheet 'includes jigging and amalgamation; flotation; cyanidation of flotation tailing; and roasting followed by cyanidaition of flotation concentrate plus amalgamation tailing. Overall mill recovery for the year 1950 was 90.2 per cent. Recovery possible by straight cyanidation of this ore would not exceed 80 per cent. The ore contains considerable arsenopyrite and pyrrhotite as well as pyrite, with lesser quantities of nickel, zinc, and copper minerals. The mineralization is for the most part extremely fine. The roaster first went into operation on August 7th, 1949, and at the end of 1950 it had roasted 10,916 tons of concentrate. The average recovery of gold from calcine during that period was 94.86 per cent in the primary stage of calcine cyanidation. The average assay of calcine residue from primary cyanidation for the entire period was 0.37 oz. per ton. Both laboratory tests and plant metallurgical balance calculations indicate a further recovery of approximately 10 per cent of this 0.37 oz. when the calcine residue is again cyanided, in the flotation tailing cyanidation circuit.

Jan 1, 1951