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By G. Stafford Whitby

N ATURAL gas is found in several provinces of Canada, particularly Ontario, New Brunswick, and Alberta. The largest producer is Alberta, and there the most important field is the Turner Valley, where some low-gravity crude oil and naphtha are associated with the gas. Last year there was produced from the Turner Valley field an average of 3,462 barrels, or about 450 tons, of oil a day. The gas flow from the wells in this field bears such a high ratio to the oil which comes from them that, despite the enforcement of a measure of conservation, it amounted to the vast quantity of 6,000 tons a day, or more than 2,000,000 tons a year. Prior to the application of any conservation measures, the gas flow was at one time of the order of 12,000 tons a day. The heat content of one ton of the gas is almost equal to that of two tons of coal. A certain amount, say, 10 per cent," of the gas is used in Calgary and surrounding towns and in re-pressuring the Bow Island gas field, but the greater part of it goes to waste. What are the possibilities of making use of this waste gas, in whole or part? The possibilities of using it profitably as fuel for domestic and industrial purposes have undoubtedly been carefully considered by the Company which now distributes a part of the gas to cities and towns in Alberta. But the relative sparness of the population and the cost of pipe lines makes such possibilities strictly limited. There are, however, distinct possibilities of making use of at !east a part of the gas for the production of a variety of chemical products and of liquid motor fuel. The present paper is devoted to outlining some of these possibilities. About three-quarters (by weight) of the Turner Valley waste gas consists of methane, the lightest and, chemically speaking, the simplest of hydrocarbon gases. The remaining quarter consists of heavier hydrocarbon gases-ethane, propane, and butane. Formerly, naphtha was separated from the well gas by a simple process of self-refrigeration. The gas coming from the wells at a pressure of, say, 1,200 to 1,800 lb., was passed through simple cylindrical vessels fitted with baffles and known as 'separators'. The pressure was allowed to drop to, say, 300 lb. in the separators, and the cooling effect secured by this expansion brought about separation of the naphtha. The naphtha thus obtained was 'wild', that is, it had a high vapour pressure owing to the presence in it of dissolved and liquefied gas. In order to reduce the vapour pressure to a level at which the naphtha could be shipped, this gas was removed either by distilling it out through a 'stabilizing' column or, according to the practice at many wells, merely by allowing the naphtha to 'weather' in open tanks (heated by coils if necessary) until the gas had been driven off in to the air.

Jan 1, 1936

By R. W. Thompkins

"PREFACEPart 1 of this paper, published in the September issue, covered the occurrence of uranium, radiation from uranium ores, the uranium series, radioactive theory, radioactive equilibrium and application to the radon series, the working level, the theory of emanation and diffusion, transport by thermal diffusion of radon emanating from porous rocks, and definitions.This Part 2, which follows, deals with radiation theory applied to uranium ores, other radon migration factors, factors affecting the radon gas release rate, the measurement of radon gas emanation rates, the tunnel concept, variation of emanation rate with grade and estimating radioactivity from grade analysis.The series will conclude with Part 3, in the November issue, which will discuss the techniques for controlling radiation and provide some example calculations.10.0. Radiation Theory Applied to Uranium Ores10.0.1. The processes of diffusion transport of radon gas, through rock from the fundamental physics is a function o f the radon gas concentration in the interstitial pore spaces and the distance from the surface. Expressed by Fick's first law of diffusion, it is expressed: [ ]10.0.2. The maximum concentration is a function of the emanating power (ß), thus the above equation may be expressed: [ ]10.1. The Effect of Porosity10.1.1. If a constant emanating power is assumed (ß), a family of curves can be obtained for concentrations at varying distances and rock porosities. The curves as originally plotted assumed a constant emanating power of 5 x 10-4 pico curies/litre/sec and show the maximum expected concentrations in the pores in pico curies per litre. Because these concentrations are proportioned to the emanating power, this set of curves can be structured to show the fraction of maximum concentrations possible at various porosities of the rock.10.1.2. Notice that at 10, 20 and 30% porosities a 5-cm sample (hand-sized and drill-sized pieces) has no practical increase in pore concentration. Thus, by measuring the emanating power of hand-sized pieces of ore, the actual radon gas production into any pile of broken ore could be estimated readily."

Jan 1, 1982

By C. H. Ash

"Abstract-The Red Chris Cu-Au deposit (522.7 Mt at 0.35% Cu and 0.27 g/t Au), northwestern British Columbia, is one of several pre-accretionary porphyry systems in the Cordillera of western Canada. It is hosted by an Early Jurassic hornblende monzonite to quartz monzodiorite porphyry which forms part of a suite of dikes and stocks that intrude Late Triassic volcanic strata. Major and trace element chemical data suggest that these Early Jurassic intrusions have compositions which fall on the boundary between alkalic and calc-alkalic compositions. Alteration and mineralization in the Red Chris deposit are more typical of calc-alkaline porphyry systems with abundant potassic, sericitic and argillic assemblages and quartz-rich stockworks. It lacks Na- and Ca-bearing silicate assemblages which characterize the alkalic porphyry deposits of British Columbia. One of the more unusual features of the deposit is the abundance of carbonate alteration and veins which occur throughout the hydrothermal history of the deposit. This type of alteration and veining is more typical of alkalic porphyry deposits. The composition of the carbonates vary both temporally and spatially with different alteration zones. Potassic zones, which are characterized by orthoclase±albite±quartz±chalcopyrite±bornite± magnetite±hematite and Au/Cu ratios of 1:1 (g/t Au:% Cu), contain minor siderite veins and alteration. Quartz-sericite-carbonate (QSC) zones overprint earlier potassic alteration and comprise quartz+ankerite+sericite+pyrite+chalcopyrite with Au/Cu ratios of 0.5:1 (g/t Au:% Cu). Ankerite is the main carbonate in this stage but has a variable composition with a more Fe-rich variety associated with mineralized veins. Localized chlorite-carbonate alteration zones, characterized by chlorite+ carbonate+quartz±kaolinite±pyrite±gypsum and high Au/Cu ratios [2 to 3.5:1; (g/t Au:% Cu)], contain predominantly calcite. Late stage carbonate-gypsum veins have an ankerite to dolomite composition which is very similar to the regional carbonate alteration and veins."

Jan 1, 1997

By F. T. Manns, G. Harper

"The Swayze gold mine is an Archean vein deposit in northern Ontario. The veins are superimposed on a conjugate joint system and are contained within an anastomosing alteration envelope in a metadiorite body. Reserves were estimated on the basis of fire assays of channel samples and car load samples from underground mine openings, surface and underground diamond drilling and surface trenching. A semi-variogram constructed from channel samples along one of the drifts yielded a horizontal, regionalized influence of approximately 9.0 m. Common industry practice has been to use 6.1 m for similar deposits in Ontario. Proven ore was defined from underground openings. The maximum extrapolation distance for proven ore along strike and dip from a data point is taken to be 6.1 m. Probable ore is extrapolated 7.6 m from a data point in a mine opening or from a drill intersection. Possible mineralization is based on geological continuity one-half the distance to a neighbouring data point.The mineral inventory estimate of 1.45 million tonnes at a grade of4.8 g Au/tonne gives an excellent outline of the geology of the deposit. The deposit contains 313 000 tonnes of ore reservesat a fully diluted grade of6.9 g Au/tonne. These figures include dilution for several reasons: (I) a 2.1 m mining width is used rather than the more typical 1.5 m width to allow for over break because of the shallow dip of some vein zones; (2) over break is allowed for adjacent to major unmineralized dykes; and (3) grams of gold are deleted from estimates to allow for the mining of unavoidable minor dykes.A personal computer with off-the-shelf software was used to compile 712 geologically defined ore blocks and sort them into a number of revealing categories. The computer was used to perform grade sensitivity tests, as well as to evaluate depth potential. Hopefully, the reiterative aspect of the method has randomized the errors and helped to cancel their effects."

Jan 1, 1987

By A. Trusiak

"Increasing energy costs in mineral processing is making it necessary for tighter controls over various parts of the concentrating process. Continuous monitoring and control of critical process streams can be easily performed by today's many computer systems. Indeed, the list of successful applications of computers to grinding and flotation control continues to grow. The day is rapidly approaching when the use of computers within concentrators for either process control or simply metallurgical accounting will no longer be a luxury, but a necessity. The benefits from such applications far out weight the initial investment.This paper describes the current application of a process control system at Brunswick Mining in north-eastern New Brunswick. Emphasis is placed on the control of a CuPb flotation circuit, and the benefits derived-from this control.No. 12 Cu-Pb Flotation: The complex nature of the Brunswick flotation process has been described else-where. 1,2,3 Four final concentrates are eventually produced, these being a Zn concentrate assaying 53% Zn, a 30% Pb concentrate, a 20% Cu concentrate, and a bulk Pb Zn concentrate assaying 35% Zn and 17% Pb. The Cu concentate, Pb concentrate, and bulk Pb Zn concentrate are all derived from a primary CuPb concentrate assaying 26% Pb, 11% Zn and 1.8% Cu.The No. 12 CuPb circuit produces approximately two thirds of the total primary CuPb concentrate. No. 12 ore, assaying 3.5% Pb, 9% Zn, 0.25% Cu and 100 g/tne silver, is ground in two parallel grinding circuits. Each line uses a 3.2 x 4.2 meter rod mill in closed circuit with two parallel 3.2 x 3.9 meter ball mills. Ball mill and rod mill discharges are classified in two stages of cycloning. The secondary cyclone overflow, or flotation feed, is controlled at 65% passing 37 microns."

Jan 1, 1981

By Peter N. Calder, Garston Blackwell

"The history and analysis of a structurally complex open-pit rock slope displacement are described. The failure involved part of the only haulage access to a major ore zone. The ongoing movement was monitored using an electronic distance measuring device and a continuous electronic system specifically designed for the problem. A major fault, infilled with a thick clay gouge, and intersected by other structural features, resulted in the transfer of weight to a rock mass acting as a buttress in the lower regions. Movements were affected by blasting vibrations and ground-water conditions. Remedial measures included limiting blasting levels and lowering the water table, following which mining was successfully resumed in the area.IntroductionBrenda Mines is situated in a mountainous region of the southern interior of British Columbia; the location is indicated on Figure 1 . The elevation is approximately 5000 ft , giving a climate typical of more northern areas. Temperatures vary from -30°C to + 30°C. A snowfall level of 400-800 cm is experienced from November to April. During the spring, a heavy runoff period occurs, increasing the pumping rate in the pit from a nominal 50* gal/min to 2000 gal/min.The orebody occurs in a fractured Jurassic rock mass referred to as the Brenda Stock; it is approximately 3000 ft in diameter and 1000 ft deep. The Brenda Stock was intruded into the Upper Triassic Nicola Group tuffs, breccias and argillites. Mineralization occurred in several stages in a relatively homogeneous quartz diorite host rock. Shearing, faulting and jointing occured later in many stages, producing mineralized clay gouge zones up to several feet in thickness'> , These gouge zones have a major effect on the stability of the pit walls.The structural geology of the pit walls is otherwise relatively simple. Figure 2 is a conventional pole diagram indicating the orientation of the rock structural systems which are present. The major system has an average dip of approximately 70 degrees to the south and strikes approximately east /west , it is not undercu t by the pit slope. Figure 3 is a photograph of part of the North wall on which this system is indicated.The basic pit design consists of a working bench height of 50 ft, with a final wall height of 100 ft between berm s and a 100-ft-wide berm every second lift. Combined with a local face slope of 50-70 degrees, the resulting wall slope, not including haulage roads, is 45 degrees. Figures 4 and 5 are generalized plans and sectional views of the pit."

Jan 1, 1980

By Shahram Tafazoli

ABSTRACT: This article presents a novel technology for sensing the size of rocks after blasting in hard rock mines. Blast engineers require rock size statistics to carefully adjust the blasting parameters. The rock fragmentation requirements vary depending on the ore type and crusher specifications. The most popular statistical parameters in the industry are the so-called P numbers (e.g., P80 and P100). A machine vision based system is introduced here for automatic image collection and fragmentation analysis of the material right inside the bucket or dipper of mining shovels. A heavy-duty camera provides the required imaging data to an embedded computer mounted inside the cab. A custom machine vision software continuously analyzes the captured bucket images and stores the suitable ones in local storage which are then fed to a Desktop software for automatic fragmentation analysis. This technology has been developed by Motion Metrics International and is commercially available as FragMetrics?.

Oct 1, 2009

By Shahram Tafazoli

This article presents a novel technology for sensing the size of rocks after blasting in hard rock mines. Blast engineers require rock size statistics to carefully adjust the blasting parameters. The rock fragmentation requirements vary depending on the ore type and crusher specifications. The most popular statistical parameters in the industry are the so-called P numbers (e.g., P80 and P100). A machine vision based system is introduced here for automatic image collection and fragmentation analysis of the material right inside the bucket or dipper of mining shovels. A heavy-duty camera provides the required imaging data to an embedded computer mounted inside the cab. A custom machine vision software continuously analyzes the captured bucket images and stores the suitable ones in local storage which are then fed to a Desktop software for automatic fragmentation analysis. This technology has been developed by Motion Metrics International and is commercially available as FragMetrics?.

Oct 1, 2009

By Shahram Tafazoli

This article presents a novel technology for sensing the size of rocks after blasting in hard rock mines. Blast engineers require rock size statistics to carefully adjust the blasting parameters. The rock fragmentation requirements vary depending on the ore type and crusher specifications. The most popular statistical parameters in the industry are the so-called P numbers (e.g., P80 and P100). A machine vision based system is introduced here for automatic image collection and fragmentation analysis of the material right inside the bucket or dipper of mining shovels. A heavy-duty camera provides the required imaging data to an embedded computer mounted inside the cab. A custom machine vision software continuously analyzes the captured bucket images and stores the suitable ones in local storage which are then fed to a Desktop software for automatic fragmentation analysis. This technology has been developed by Motion Metrics International and is commercially available as FragMetrics?.

Oct 1, 2009

By V. G. Papangelakis, A. Dani

"Alkaline pressure oxidation, particularly in the presence of trona as additive, can be used to oxidize high carbonate refractory gold ores as it prevents the formation of CO2 in the autoclave. However, the presence of silica in the ore can lead to the encapsulation of pyrite due to the solubility of silica in alkaline solutions and its subsequent reprecipitation on the reacting pyrite surface, leading to the formation of a passive layer. This fundamental study investigates the chemical composition and thickness of the passive layer on a rotating pyrite disk using XPS and SEM, as a function of process conditions at 230°C, in an aqueous slurry containing silica sand, sodium carbonate and calcium carbonate under 100 psi of oxygen overpressure.INTRODUCTIONAlkaline pressure oxidation (POX) has been used successfully to treat high carbonate refractory gold ores, which contain carbonates in addition to sulphides, most notably at Mercur and Goldstrike mines operated by Barrick Gold. There are several advantages to using alkaline POX over its acid counterpart, especially due to high carbonate content. First, it eliminates the production of CO2 in the autoclave without resorting to pre-acidification, which allows for high oxygen utilization. Second, alkaline POX suppresses the formation of elemental sulphur and intermediate sulphur oxyanions (such as thiosulphates and dithionates), which reduce gold recovery. Third, the use of sodium hydroxide or salts prevents the formation of anhydrite scale by forming soluble sodium sulphate. Other advantages are the use of cheaper materials of construction and the formation of non-acidic residue that do not require further treatment prior to cyanidation (Thomas, 2005).Sodium carbonate in particular is a promising reagent for alkaline POX because it was shown to significantly accelerate the kinetics of pyrite oxidation by molecular oxygen, when compared to other reagents such as sodium hydroxide, sodium borate and calcium hydroxide. This has been attributed to the following factors: a) the faster oxidation kinetics of Fe2+-CO3 complexes compared to Fe2+ oxidation, b) the buffering effect of carbonate ions on the acidic pyrite surface, and c) the increased solubility of oxidizing Fe(III) species due to carbonate complexation (Caldeira, 2010)."

Jan 1, 2012

By P. L. Claessens, S. Belisle, C. Bowen

"Use of zinc shot feed is a well-established procedure among North American electro-galvanizers. This form of zinc is easy to handle and relatively inexpensive when compared with zinc oxide. This paper reports results on the kinetics of zinc shot dissolution in traditional pure zinc solutions and in electrolytes used for the plating of nickel/zinc alloys. Despite the cementation of minor amounts of nickel in the latter solution, acceptable dissolution rates of the zinc shot can be achieved through proper adjustment of the solution velocity. Under these conditions, the nickel shell produced by cementation is continuously abraded, exposing the underlying zinc.IntroductionThe use of insoluble, noble metal-containing anodes rather than soluble zinc anodes for the operation of high current density electro-galvanizing lines has gained almost universal acceptance. Two major reasons for this trend are:• improved control of the process by virtue of constant inter-electrode distance; and• increased productivity because the operation of the lines does not require the relatively frequent interruptions for replacement of consumed anodes .The results of the principal anode and cathode reactions are, respectively, depletion of the zinc content of the electrolyte and the increase on its acidity;"

Jan 1, 1991

By Lang Tao, Jun Wang, Wei Xiao, Wenqing Qin, Pan Cao, Guanzhou Qiu, Key Lab of Biohydrometallurgy of Ministry of Education, Central South University

"The effect of metal cations on the rutile flotation using styryl phosphoric acid (SPA) as the collector was investigated by micro-flotation test, bench scale flotation test, zeta-potential measurements and adsorption measurements. The micro-flotation results indicated that Fe (?) and Al (?) ions in low concentrations had obvious activation on the rutile flotation, and Pb (?) ions in low concentrations had smaller activation of rutile, but Fe (?), Al (?), Pb (?), Ca (?) and Mg (?) have strong inhibition of rutile flotation in high concentrations. The bench scale flotation results indicated ethylene diamine tetraacetic acid (EDTA), boracic acid, and sodium hexametaphospate can decrease the metal ions concentrations, and increase the recovery of rutile flotation. Adsorption measurements and zeta-potential measurements revealed that Fe (?), Al (?) and Pb (?) ions were adsorbed on the rutile surface, and had interaction with SPA. But when these ions concentration were over the largest adsorption capacity, residual metal ions could occur chemical reaction with SPA.INTRODUCTIONRutile is one of the favored minerals for production of titanium dioxide white pigment, primarily through the chloride manufacturing process (Stanaway 1994; Hou et al., 2013) However, the majority of rutile ores belong to refractory ores, while flotation is one of the most efficient methods to separate fine rutile from gangue (Dolbear et al., 1937). With the flotation development, many effective collectors were successfully applied in the oxide ore. Many reviews have indicated that organic phosphonic acid collectors showed good selectivity on oxide ores such as ilmenite and rutile (Bulatovic & Wyslouzil 1999; Liu & Peng 1999).It is inevitable that many types of metal cations are present in ore pulp. These metal cations significantly influence the flotation of minerals. Liu et al. (2015) showed that Ca2+ and Mg2+ could improve the floatability of spodumene at pH 12.5 and 10.0, respectively. The authors proposed that Ca2+ and Mg2+ ions readily form hydroxy complexes (CaOH(l) and MgOH(l)) and precipitates as (Ca(OH)2 and Mg(OH)2) in strongly alkaline solutions. Fan and Rowson (2000) investigated the effect of Pb(NO3)2 addition as an activator on ilmenite flotation and showed that it could improve ilmenite floatability. The addition of Pb(NO3)2 resulted in an increase of ilmenite zeta potential in both weakly alkaline and acidic aqueous solutions. Mehdilo, Irannajad, and Rezai (2015) studied three kinds of ilmenite of different origins and discovered that both Mg and V had a negative correlation with ilmenite flotation, while the Mn content seemed to correlate positively with flotation efficiency. A number of studies have also showed that Fe3+ can improve the floatability of ilmenite (Fan et al., 2009; Nuri, Mehdilo, & Irannajad, 2014)."

Jan 1, 2016

By J .. R. Brown, G. Deschenes

X-ray Photoelectron Spectroscopy (XPS), X-ray Diffraction (XRD) and Electron Probe Micro-Analysis (EPMA) were used to characterize chemically the gold complex adsorbed on activatedcarbon from a solution containing 102mglL Au and 0.5 giL thiourea. This paper also considers the gold chloride and the gold cyanide systems. The results indicate gold is adsorbed on activated carbon from the thiourea solution as the gold (I) thiourea complex, i.e. Au [CS (NH) 2];' Other gold species such as metallic gold were not detected on the carbon support. These results also suggest the elution of the gold (I) thiourea complex can be performed with high recovery.

Jan 1, 1993

"The Waite-Amulet, an important copper-zinc mine, lies astride the Duprat-Dufresnoy township boundary about 8 miles northwest of Noranda, Quebec. It is an amalgamation of two properties, that of the former WaiteAckerman- Montgomery Mines to the north and that of Amulet Mines, Limited, to the south. This amalgamation took place in 1933. The description that follows is confined to the Amulet section.Ore was first discovered on the Amulet property in the autumn of 1924. The C Shaft and Upper A orebodies were found in 1925 and the F orebody in 1929, the latter by diamond drilling under a swamp. Under the present management, Lower A ore body was discovered by diamond drilling at a depth of 700 to 1,200 feet in 1938, and new ore was found from the old C Shaft workings between 1943 and 1945.From April 15th to October 20th, 1930, 60,291 tons of ore was produced from the Amulet. During the second half of this period, the ore averaged 4.2 per cent copper, 16.3 per cent zinc, and 0.02 oz. gold and 3.35 oz. silver per ton. Due to the prevailing low prices of metals, there was no further production until July, 1937. Output was greatly accelerated in 1940 when the newly found Lower A orebody assumed the main burden of production. Up to January 1st, 1946, mill reports indicate the treatment of the following ore: GENERAL GEOLOGYFig. 1 shows the geology of the entire property. To the east is the Lake Dufault granodiorite stock and to the west the Flavrian Lake granite mass. Around the granodiorite and separating the Waite from: the Amulet section is an older diorite intrusion. The ore occurs in a series of lavas that form a broad anticline pitching eastward at a relatively low angle into the Lake Dufault intrusives. There are several steep east-west faults. The late Powell diabase dyke is shown, also the general areas of strong dalmatianite alteration, a type closely associated with the sulphide mineralization."

Jan 1, 1954

By Håkan Schunnesson, Kirsten Holme

"When mining high grade, narrow ore bodies, the mining method often implies a very detailed knowledge of the ore contacts to avoid unacceptable ore loss and waste rock dilution. During the past decade, the use of microprocessor based drill monitoring equipment has become an accepted technique, even for percussive drilling. On the basis of the recorded drill performance, such as penetration rate, torque pressure, thrust etc., a fast evaluation of the lithological sequence of the ore zone can be made. In order to evaluate the potential of percussive drill monitoring to pro-vide detailed information of the geometry of the ore body, the technique was tested in the Viscaria copper mine in Sweden during 1996.To provide understandable information to the mine geologist, great emphasis was placed on the separation between the drilling response generated by variations in rock conditions from variations caused by the operator and the drill system. Due to the complicated geology in Viscaria, the drilling response presented to the geologists was separated in two independent signals, one representing the hardness of the rock and one representing the in homogeneity(fracturing) of the rock. With those signals a good separation between different rock types in the ore horizon was achieved.The experience from the Viscaria copper mine is that drill monitoring not only can be used to locate contacts between rock types, but also to characterize rock conditions and, often, also to specify the exact rock type present. Because it is possible to get the drill monitoring information very quickly it is a valuable complement to diamond drilling for increasing the specific knowledge of the geology and the ore body."

Jan 1, 1997

By E. Poiate, P. R. Cabral, A. V. N. Santos, P. V. M. Costa, C. S. Amaral, A. M. Costa

This paper discusses the design of underground salt caverns, opened by solution mining, for the production of brine and storage of natural gas under high pressures. The caverns are located in the salt basin in Maceio City, Alagoas State, at the northeast region of Brazil. Special attention is given to the geomechanical structural design of the caverns using computer codes specially developed for the simulation of excavations in salt rock formations, considering validated constitutive creep laws under different initial stress states and temperatures. The behavior of sedimentary rocks intercalations presented in the salt layer is simulated using elastic-plastic models. The excavation of the caverns by solution mining is also simulated starting from a geostatic initial equilibrium state of stresses, with a unique formulation only implemented in these computer codes, without the need of the application of boundary stresses to the model in order to develop the initial state of stresses. These computer codes have being used in the design of several clusters of caverns for brine production used as raw material of Poly Vinyl Chloride (PVC) of the Chemical Industryin Brazil. These computer codes and methodology were also applied to the design of the underground conventional potash mine in the state of Sergipe, overlying tachyhydrite and carnallite with very high creep strain rate. They have also been used in the design of the pre-salt oil wells through thick layers of stratified salt rock in Santos Basin, for the exploration and production of the pre-salt reservoirs in Brazil. The constitutive creep equations implemented in the codes are based on a double mechanism creep law. The creep constants adopted in the simulation are taken from a previous investigation carried out on an experimental panel of the potash mine, considering the stratified geology with different salt rocks of the basin where the mine is located. These constants were also obtained by lab tests under different confined and differential stresses and temperatures.

Jan 1, 2015

By Arsalan Talebzadeh

Construction -Surface ?First two intake fans constructed in 2007; third fan added in 2008 to reduce resistance in the system. 450 HP fans. ?Excavation for exhaust fans started in 2008. ?In parallel with underground construction in preparation for the changeover. ?Bulkhead in place prior to completion/ commissioning of

Oct 1, 2010

By J. R. Giegerich

Purpose It is the purpose of this paper to describe the application of underground conveyor systems to the transportation of ore in the Sullivan mine of The Consolidated Mining and Smelting Company of "Canada, Limited, at Kimberley, British Columbia. General Applications Conveying has been recognized as a means of underground transportation for a great number of years but only during the past fifteen to twenty years has there been any extended application of the method to underground metal-mine operations. Coal miners became conveyor conscious before metal miners. Probably one reason for this is the fact that there are more flat coal seams than flat orebodies. A second reason is that coal is light and is a less abrasive material than most metallic ores. The vast improvements made in belt construction during the past few years, together with improvements in mechanical conveyor equipment, have gone a long way in making this form of transportation attractive to the metal miner. In new mines being opened today, or in major extensions to older mines, the possibilities of conveyor transportation should receive serious consideration. There may not be any widespread application of the belt conveyor as a replacement for the conventional hoisting and locomotive haulage. Where there is an application, tl1e saving in cost can be appreciable and many operating ad-vantages gained because of ease in operation.

Jan 1, 1951

By G. Gabra

"A process of leaching niobium oxide from pyrochlore concentrate using hydrofluoric acid is described. Variables such as acid concentration, temperature, reaction time, solid/acid ratio, agitation speed and particle size are correlated to the recovery of niobium oxide.The relatively low activation energy (1,86 Kcal/mole) and the dependence of reaction rate on agitation suggest that the process is diffusion controlled. The optimum conditions for extracting niobium oxide from the leach solution, using either methyl isobutyl ketone or tributyl phosphate have been determined.IntroductionMost of the commercial production of niobium and tantalum has been derived from the treatment of columbite - tantalite minerals.In recent years (1960) , pyrochlore mineral has been found to be an alternate source of niobium . This mineral varies widely in composition and contains in addition to the main elements of calcium , sodium and niobium, some tantalum, fluorine, rare earth elements, titanium, alkali an d alkaline earth elements.It is well known that the province of Quebec possesses several pyrochlore niobium deposits totalling approximately 151 million ton s at an average 0.45% niobium oxide(1). One of the deposits, the St-Honor carbonatite, was brought into production by Niobec Inc. in 1976. Flotation o f this material produces a concentrate of about 60% Nb205(2).In view of an expanding niobium market in recent years and the presence of large niobium deposits in the province, a research and development program was initiated at the Centre de Recherches Miner ales to evaluate known processes for the separation of niobium and tantalum from each other as well as their purification . Some work has also been undertaken at the CRM to develop an improved extraction process. T his work will be the subject of further communication s."

Jan 1, 1985

By C. Matthews, A. Vo

"Australia is one of the world’s leading exporters of bulk commodities and the extensive use of sampling equipment is key to the successful management of each mining operation. At the process plant, without a full understanding of the feed, product and tails, it is impossible to fully optimise the performance of the plant, such that the metallurgical balance is often open to error. At the port, a statistically correct, bias free and compliant sampling system is crucial to ensuring exported minerals are reflective of their true value and to avoid penalties. Over the last decade, as a result of the iron ore boom, there has been high demand for reliable, representative and standard compliant solids sample systems in Australia. This paper reviews several solids sampling applications at Australian mine sites, the challenges and experience gained and how the implementation of reliable representative sampling systems has provided better understanding of plant process performance, improved plant control and overall benefits to the operations.INTRODUCTION Mining is the primary contributor to the Australian economy with Australia ranking in the top 4 in economic resources for 21 primary industrial minerals in 2016 (Britt, et al., 2017). Australia is one of the world leaders in the export of the majority of its commodities including gold, copper and iron ore (Britt, et al., 2017). Therefore, a suitable and standard compliant sampling system is essential for evaluating plant performance and content verification. At the mine and at the port, the larger iron ore miners in Australia have developed stockpile models to predict the grade of their ore down to individual blocks of the stockpile. This allows the miner to create the right blend of material for sale to their customers and ensures they are not underselling their product or at risk of penalties for impurities or low grade. As an example, the average difference between the benchmark 62% Fe and low grade 58% Fe fines at the time of this report averaged US $30/tonne according to the Metal Bulletin Iron Ore Index. At a shipload of 180kt this would be a variation of US $5.4M. Whilst this is an extreme example, it highlights the economic importance of producing the correct grade product and a recognised representative sample of said product."

Jan 1, 2019