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By J. W. Reynolds

Use of crushed waste rock recovered by sink-float separation from normal ore production for backfill is an established procedure at Commco's Sulhvan mme, Kimberley, British Columbia. Need for a safe method of placement in voids which were difficult to reach by gravity methods led to a co-operative venture with Radmark Engineering Ltd. in the development of a workable pneumatic transportation system for rock material. This paper reviews work done to date in a current program, and includes comments on the nature of the fill so placed, options for cementing such fill, implications for other aspects of mining and references to other applications of the system by other organizations who exchanged experiences with the Sullivan mine staff during the five-year period reviewed.

Jan 1, 1972

By S. J. Prout, J. M. Lang, D. Lascelles, K. Sarinas

"There is a growing demand for ore characterization methods to support metallurgical development programs from a true geometallurgical perspective. Today, there are multiple automated mineral analysis systems on the market, many of which are based on conventional mineral liberation data. However, liberation data can be limited when assessing the floatability of a mineral to predict its recovery as it doesn’t consider the surface area available for collector absorption and bubble attachment; whereas mineral exposure measurements can. Using the First-Order Rate equation to predict the recovery versus time of variously exposed particles, a model has been developed to predict the recovery of copper sulphides at a particular grind size. This model provides the opportunity for the prediction of copper recovery and grade from multiple, small-scale samples. These predicted values can be imported into resource modeling software, and guide the domaining of geometallurgical units within the ore body. Data has been analyzed from various global copper porphyry systems and compared with actual flotation testwork.IntroductionAs part of the development of a mining project, resource estimation primarily focuses on the definition of the quantity and grade of the ore in the deposit; as the project evolves from preliminary economic assessment through to feasibility, the geological model is usually further populated with hardness and recovery data.The CIM Definition Standards (2011) identifies measured mineral resource as the part of a mineral resource for which quantity, grade or quality, densities, shape, and physical characteristics are estimated with confidence sufficient to allow the application of “modifying factors” to support detailed mine planning and final evaluation of the economic viability of the deposit as an asset. The modifying factors include, but are not restricted to, mining, processing, metallurgical, infrastructure, economic, marketing, legal, environmental, social and governmental factors.With market fluctuations, many investors in the mining industry have become more and more risk averse which has increased the demand for more reliable data to support these modifying factors. This has led to the widespread use of geometallurgy and statistical analysis to better inform the resource estimation. Geometallurgy is used to characterize ore variability and is especially useful for highly variable or strongly zoned deposits, several close deposits that will be milled together, projects requiring complex or new metallurgical approaches, brownfields or sight-of-mine exploration, expansion projects that exploit new, deeper or adjacent reserves, and projects with significant legacy drill core that are being re-evaluated due to new economic circumstances."

Jan 1, 2018

By D. R. Jolley

"The selection of equipment for open-pit mining is an important decision which results in a considerable capital expenditure by the operator. The decision is complicated by the wide product range on the market. Certainly, equipment performance is an important criterion to consider in making the decision. Equally important, however, is the operating inter-relationship among the equipment. A poor balance increases production costs and waiting time as queues form at the bottlenecks. This inter-relationship is dependent on equipment performance, but it is also affected by management decisions (i.e. scheduling techniques).The purpose of this paper is to show how the computer is used to decide which equipment and operating decisions achieve the required production objectives at least cost. Actual mining of the pit is simulated over a period of time using different equipment and scheduling decisions. Production, waiting time and costs are evaluated for each alternative until the operator is satisfied that he has achieved the best result."

Jan 1, 1970

By W M. Cameron

Geophysical studies have extended seaward in recent years, and the important discoveries which have been made have led to a better understanding of geological processes. A present source of certain minerals, the sea will eventually serve as an important source of desalinated water. The continental helves, in particular, represent a potential mineral resource. The expansion of Canadian oceanographic effort that is now underway will eventually lead to the exploitation of the wealth beneath the sea. THE subject of this symposium, which emphasizes the word "geophysics," the specialties of the speakers who are contributing and the nature of the audience at first made me believe that I, a a physical oceanographer, would be out of place. However, I shall undertake to classify myself as a geophysicist, and shall arrange my remarks on my specialty o that they might be of interest to those of you who are predominantly geologists, metallurgists or mining engineers.

Jan 1, 1963

By M. R. Khalesi, S. Bellec, C. Bazin, D. Hodouin

Batch grinding tests conducted on a gold ore indicated that gold is not randomly distributed within the size fractions of the ground ore. Since gold leaching performances were found to be dependent of the size of the gold carrying particles an integrated gold ore grinding-leaching simulator should incorporate a method to predict the gold size distribution of a ground ore. The paper describes the results obtained from batch grinding tests showing the non random distribution of gold within the size intervals of a ground ore and the initial developments of a grinding model to predict the gold size distribution in a batch grinding product.

Jan 1, 2011

By J. C. Gathje

Newmont&apos;s Phoenix Project is located near Battle Mountain, Nevada and is scheduled to produce copper concentrates containing high precious metal values. High temperature pressure oxidation (PDX) of the concentrates was considered as a treatment option during process development. The metals content in Phoenix concentrates range from: 15-25% for Cu, 1-10% for Zn, 0-2% for Pb and ?27% Fe. The precious metals content of the Phoenix concentrates can range up to ?300 g/t Au and >3,000 g/t Ag. As a consequence it was necessary that any process for consideration should have the capability of recovering both the copper and precious metal values. Typically, gold can easily be leached from the autoclave discharge solids, but silver is chemically bound with the jarosite formed and cannot be directly leached. Laboratory investigations led to the development of a patented PDX process that minimizes the formation of jarosite so that the silver can be leached easily along with the gold. The process was confirmed with extensive pilot plant testing. Excellent solution extraction of copper and zinc was achieved, and both iron and lead were precipitated in the PDX residue. The process produces clean PDX discharge liquors with very low iron concentrations. As an example, conventional PDX techniques resulted in pregnant liquors containing ?5 g/L Fe. However, the Newmont process, which controls the iron and sulfate species, achieved high iron precipitation in the PDX solids and pregnant liquors containing <0.5 g/L Fe. High gold and silver recoveries were achieved by direct cyanidation of the PDX solids. This process has the added benefit of producing PDX solids that demonstrate superior settling and filtration characteristics.

Jan 1, 2006

By S. Akhlaghi

In many electronic/optoelectronic devices, interaction between the metal stack and solder is undesirable. If a reaction happens, a nonuniform joint containing spikes and voids is likely to form and as a result the heat dissipation deteriorates significantly, which in turn, leads to the degradation of the bond. In the present work the interaction between Ti/Mo/ Au metallization system, which was sputter deposited on AlN substrates, and Pb-Sn solder was studied by using scanning electron microscopy (SEM). Also, an EDX system was used to trace the changes in chemical composition of the layers after solder tests. The microstructural examinations show that the Ti and Mo layer from the Ti/Mo/ Au metallization system are not impermeable enough and thus Ca from the surface of the substrate moves all the way up to the interface of Au/Mo and forms an intermetallic at the interface, which grows over time.

Jan 1, 2006

By Ramin ArameshAsl

Urumieh-Dokhtar is the well-known vast metallogenic belt extended from NW to SE of Iran and basically is referenced in copper mineralization studies in Iran. Hashtjin 1:100000 sheet (NW Iran) is located on this belt and rock units are consisted of Oligocene intrusive, volcanic rocks and Eocene Sedimentary rocks. Concerning the significance of identifying the alterations and faults zones in copper exploration, the aim of this study is identifying the copper mineralization by multi-spectral analysis of ASTER (Advanced Space borne, Thermal Emission and Reflection Radiometer) satellite images in the limitation SD-SWIR (Spectral Domain of Short Wave Infrared). Several analytical methods are implemented in this study such as SAM (Spectral Angle Mapper), MF (Matched Filtering) and PCA (Principal Components Analysis). These methods have been utilized for recognizing the Argillic, Propylitic and Sericitic alteration zones and all of them are relying on the remote sensing methods as well as geological studies of new targets for copper mineralization identification in the area.

Aug 1, 2013

By G. Shaw

IN recent years, most of the reconnaissance work of the Geological Survey of Canada has been mapped on a scale of 1 inch to 4 miles. Topographic base maps, commonly made from aerial photographs, were available to the geologist for such work. The advent of war curtailed aerial photography for civilian purposes, and by 1941 all areas already photographed had been geologically mapped. Nevertheless, the need for geological maps to assist post-war prospecting was so apparent, and the country to be covered is so vast, that some new method of rapid mapping had to be devised. It was felt that the need would be met if geological maps could be produced at a scale of 1 inch to 8 miles, provided they were sufficiently accurate in topographic detail to serve as guides to travel. Though in such maps there would be considerable sacrifice of geological detail, they would serve to outline, at least approximately, the major geological units, some of which might prove of sufficient interest to warrant later detailed study. It seemed that such mapping would be particularly useful in the northern regions of Canada which the work of early explorers has indicated are underlain largely by granitic rocks. These, so far as is known, are barren of mineral deposits, but within them are known to be areas or bands of &apos;greenstones&apos; of the type that, in some localities, have been found to contain valuable orebodies. The problem, then, was to devise a method of mapping, particularly of such greenstone bands, that would make it possible to cover a relatively large area-say 30,000 square miles-in one season and at a cost below that of 4-mile mapping, with, of course, some sacrifice of accuracy. The problem seemed to be threefold: (a) to observe as much of the bed-rock as possible; (b) to produce a topographical map of as much of the area as possible, with particular reference to portions of geological interest; and (c) to cover as large an area as possible in a limited time, which meant faster modes of travel than have hitherto been used. The obvious answer to all three phases of the problem was the use of aircraft. If rock types could be broadly differentiated from the air, reconnaissance traverses by air would supply the answer to the first part of the problem. For topography, air photographs taken on reconnaissance flights appeared to be the answer. For the third phase of the problem, the use of aircraft was ideal.

Jan 1, 1943

By K. Iturralde

The topic of this article is the automation and robotization in refurbishment processes of industrial buildings. The need to mold these production spaces is quite universal. Particularly in the regions with a high industrial development and with a lack of buildable land, there is a need to convert this kind of spaces into an improved production system. The latest developments can be a useful tool for achieving a more efficient way of reforming this type of construction. On the one hand we have the digital or computerized 3D Laser Scanning (Computer Aided Measurement) that allows an accurate 3D modeling of the entire building. On the other hand, the project management using BIM (Building Information Modeling) could provide an easy design of each of the elements of the refurbishment. Finally, through the production of construction elements using robotics as jig or for CNC (Computer Numerical Control) we achieve a neat production of each element. How can be all those technologies applied in the refurbishment or expansion of industrial buildings? The research takes a first approach and analyzes industrial buildings that can be called generic or not specialized. To narrow the field of refurbishment, three major factors are defined. The first is to minimize the bill of the energy consumption of the buildings. This could be done either insulating the envelope, reducing the waste-volume to be conditioned climatically or creating facilities for energy production. The second is that the refurbishment or expansion of industrial buildings should try not to interfere on the production process that takes place in the building. In other words, the assembly of the elements in the construction site should be quick and easy, causing the least of disturbance at the workplace. Finally, the research makes an approach towards a robot integrated industrial or productive building .

Aug 1, 2013

By J. Grant Spratt

THE Turner Valley gas-field, situated some thirty miles southwest of Calgary, Alberta, has been the topic of much discussion, particularly from a geological viewpoint. Several papers (1, 2, 3, 4, and 7) dealing with the structural and stratigraphical geology have already been published and are available for reference(l). In this article, the geological conditions will be treated only as they directly refer to the crude-oil prospects along the west flank of the anticline. HISTORY During the past twelve years, Turner Valley has been known mainly as a field which has produced a high-gravity naphtha from relatively large quantities of gas. For about ten years prior to the discovery of this naphtha-bearing gas, which is produced within the upper 450 feet of a dolomitic limestone of Carboniferous age, a minor production of light crude-oil was obtained from overlying sands of Cretaceous age. Up to June 1st of the present year, the field had produced 9,473,582 barrels of naphtha from approximately 829,000,000 M.c.f. of gas. For the past four years, the total daily production of 80 to 90 wells has averaged about 3,200 barrels of naphtha from 250,000 M.c.f. of gas. This is an average of 13 barrels per million cubic feet. The naphtha is extracted from the gas by ordinary gas-oil separators and absorption plants. After the naphtha has been recovered, about ten per cent of the gas is marketed for fuel to supply the cities of Calgary and lethbridge and intermediate cowns. The remaining ninety per cent is burned to the atmosphere, with the exception of some four to five million cubic feet per day which the Calgary Gas Company score in the depleted Bow Island gas-field.

Jan 1, 1936

_What is standard technology infrastructure _ Business Context _ The mine operator?s technology challenges and needs _ The benefits of technology standards _ Overview of the SMART initiative _ Technology standards description _ Current status _ Next steps What is Standard Technology Infrastructure Technology Infrastructure is: ? Networking communications ? Computing operating systems ? Hardware platforms ? Data storage and access ? Operator interface _ These components are based on recognized open standards organization, and _ Commonly and widely utilized by industry, and _ Commercially available off-the-shelf systems (COTS), both hardware and software _ Standard capability to provide immediate and open access to raw or derived data at source, APIs, configuration parameters & sub-routines from all system components; ALL CURRENTLY AVAILABLE

May 1, 2008

By P. W. Jensen

Gold deposits in Interior Alaska are commonly coincident in time and space with reduced, mid-Cretaceous granitoids. The True North deposit of the Fairbanks district is several km from such granitoids, but yields mineralization ages indistinguishable from the Fort Knox granite-hosted deposit. True North, however, resembles sediment-hosted epithermal Au, demonstrating the variability of intrusion-related Au deposits in metamorphic rocks. The True North deposit (14M tons at 1.5 gpt) is hosted within a carbonaceous thrust complex separating eclogite facies from amphibolite facies rocks, located > 5 km from mineralized granite outcrops. The ores contain anomalous Sb, As, and Hg (stibnite is the most common sulfide) with ankerite-sericite alteration in steep NE-striking ?feeder? shears and low angle thrust shears. Nearest hornfelsed rocks are located > 1 km away, and across several high-angle faults. Fluid inclusion data indicates trapping temperatures of ~250C from low-density, low-salinity fluids at P < 0.5 kb. Au was originally present as solid solution in sulfides; minable ores are restricted to the oxidized upper 100 m of the deposit. The considerable differences between this deposit and the temporally equivalent Fort Knox intrusion-hosted deposit indicate no one description adequately characterizes this deposit type.

May 1, 2003

By D. C. Downing

"I THANK YOU for the invitation which The Mining Society of Nova Scotia extended, originally to Gordon Berry, manager 'of our Point Tupper Refinery, to join you at this meeting and discuss refining and petrochemicals in their relation to this region. There are natural advantages in Nova Scotia which have made possible, and will continue to make possible, sizeable developments both in petroleum refining and in chemicals. Equally, however, as is the case everywhere, there are certain constraints. For clarity in this presentation, I will state some of these constraints right at the beginning. First, of any future developments from now on, only a small proportion of the products can be expected to go into local markets. I can make the point best with a few figures. Petroleum companies all have market forecasts. None ever work out to be perfect, but the trends are relatively predictable and the orders of magnitude are certainly correct. Estimates for the use of all refined petroleum products in the four Atlantic provinces are:"

Jan 1, 1973

By G. Knight

"Results of a program of dust research carried out at the Mines Branch Laboratory, Elliot Lake, indicate that dust-concentration estimates vary greatly, depending on the sampling instrument, the assessment technique and the properties of the dust cloud. The wide range of the ratio between the estimates by any pair of instruments shows that the correlation between the health hazard and dust-concentration estimates by most existing sampling instruments must be questionable. Important studies are being carried out to permit the definition of mine environments in more precise technical terms. The influence of size selection, the physical property measured, composition and sampling period on the assessment of the health hazard are discussed."

Jan 1, 1969

"A growing public awareness of work-related diseases such as pneumoconiosis and the impact of this awareness on legislative bodies and on the skilled labour market are reasons why the Canadian mining industry must consider dust control of top-drawer importance. Measurements and standards related to the hazard are necessary to control a dust situation and to avoid excessive risk. The author discusses some of the methods of measurement, standards proposed and terminology used in this developing technology. The purpose primarily is to give a better understanding of the basic advances achieved by those who have applied current knowledge with a measure of success."

Jan 1, 1972

By J. W. Gregg, P. M. Dranchuk, D. L. Flock

"From preliminary investigations it has been observed that although evaporation losses may be estimated by comparing single values of certain physical properties of crude oils and their evaporation residues, such techniques possess little accuracy unless both the evaporation process and the variation of the property as a function of the process are completely known. The accuracy of estimation may be increased somewhat through the comparison of property mid-per-cent curves. Further increases in accuracy are possible if bottoms yield •curves rather than mid-percent curves are used. The use of both the mid-percent and bottoms yield curves however involves a prohibitive amount of effort in most cases. Examinations of distillation bottoms from Hempel type distillations carried to end points just short of the cracking point have indicated that these bottoms are not appreciably affected by the evaporation process. It was further observed that bottoms of identical API gravity, obtained from a crude oil and its evaporation residues behave as if they were pure components which were unaffected by evaporation. Based on these observations Hempel distillation bottoms of equal API gravity were obtained for a crude oil and its various evaporation residues from API gravity bottoms yield curves. The volume percent of these bottoms in the crude oil and its residues were used to calculate the evaporation losses suffered by the crude in order to yield the various residues. The results indicate that, although further refinements in technique are required, it is possible to calculate evaporation losses with an accept-able degree of accuracy through the use of this method."

Jan 1, 1960

By J. L. Llanca

The New Level Mine project (NLMP), the planned underground expansion of the El Teniente mine in Rancagua, Chile, is expected to reach a daily extraction rate of 137 to 180 ktpd upon achieving full capacity. Production is planned to start in the year 2017 and the current plan is to meet that target through two development phases, from the year 2012 to 2014 and from the year 2015 to 2017. To achieve the 2012 to 2014 underground development schedule, the ventilation requirements have been estimated in the range of 189 m3/s (400 kcfm), and cannot be made available without significant modifications to the current system of El Teniente. As a result, a certain number of alternatives were explored to find a solution to this shortfall, for example, adding raises to generate parallel airways and installing fans to reinforce the current ventilation system. From the alternatives studied, the installation of a second main fan (system) in parallel to an existing one was identified as the best solution, and selected for implementation, however the location was not ideal and there were concerns as to the operation of both fans once the second fan was installed. This paper presents the study used to estimate the operational points of both the current and the new fan, and to justify the parallel installation of the additional main fan. An additional computational fluid dynamics study was undertaken to validate the operational point, given the particular geometry of the fan?s location and placement, to guarantee a stable operation of the fans. Finally, the protocols arising out of this work for starting the fans, and operating them in parallel to avoid generating a stall condition and damaging the investment are discussed.

Aug 1, 2013

By U. Martin

Advanced copper materials for conducting applications require an optimal combination of high mechanical strength at ambient and moderately elevated temperatures together with superior electrical and thermal conductivity. Mechanical alloying under repeated cooling of the milling vials in liquid nitrogen has been applied to produce ultra-fine grained (UFG) oxide dispersion strengthened (ODS) copper with a high yield strength at ambient temperature. In the present study ODS copper was manufactured by mechanical alloying of copper powder and 3% by volume of incoherent oxide dispersoids. During the high-energy milling a homogeneous distribution of fine dispersoid particles (diameter nearly 100 nm) can be achieved in the powder. Samples with a density of more then 97% of theoretical value were produced by uniaxial hot pressing under 650 MPa at 600°C for 20 minutes. The high yield strength at ambient temperature can be described by a linear superposition of the Orowan stress for particle hardening and of ultra-fine grain strengthening according to the Hall-Petch mechanism. Simultaneously, a best value of 75% IACS could be obtained for the electrical conductivity. The creep behaviour of ODS copper in the temperature range from 500°C to 700°C is described within the frame of diffusional creep deformation.

Jan 1, 2007

By S McQuitty

The metallurgical treatment of Falconbridge ore re-quires an extremely fine grind of the pyrrhotite portion ? for maximum liberation and recovery of nickel. This paper describes the operation of a grate discharge pebble mill in closed circuit with cyclones regrinding 25 to 30 tons per hour of sulphides to approximately 90 per cent minus 325 mesh. The consumption of the screened ore grinding medium is of the order of 2.5 pounds per kw.-hour, or less than 1 per cent of the tonnage of re-ground sulphides. IN RECENT years, there has been a considerable interest in pebble grinding in the uranium industry, and a number of installations have appeared. However, the use of sulphide ore pebbles as a grinding medium has so far been relatively limited. There has also been some question as to their suitability for the very fine grinding of sulphide concentrates. This paper describes the preliminary results of a commercial operation involving the

Jan 1, 1964