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Applications of proven real time, through-conveyor elemental analysis technology and benefits achieved will be discussed using case studies in base metals, iron ore and phosphate operations. PGNAA (Prompt Gamma Neutron Activation Analysis) technology and its background in minerals applications and applications which are expected to further improve its utilization will be reviewed. Short payback through operational benefits such as removal of waste from feed, increased feed grade and overall improved productivity will be demonstrated based on results achieved at several processing operations. PGNAA technology is most applicable to conveyed flows as it is unaffected by belt speed, particle size, segregation/layering, mineralogy or dust. As a transmission method able to penetrate in excess of 500mm of rock it provides extremely representative results continuously measuring through the full conveyed cross section and reporting results typically on one to five minute accumulated increments to the control room. Multi-elemental results and moisture content are used for active process control: diverting conveyed flow increments(bulk sorting), blending ore types in plant feed, and providing advance warning of significant quality changes to the downstream plant operators (e.g. flotation). Elements of interest may include deleterious components as well as target metals. Ore feed quality measurements are also useful in metal accounting, ore reconciliation and real time feedback to mining operations. Further benefits can result when combined with other technologies such as particle sorters, to upgrade diverted increments of subeconomic material to achieve higher feed grades and lower deleterious content to the main process. Measurement of elements (e.g. silica) which correlate with ore hardness or grinding characteristics can be used to moderate feed rate to grinding mills to prevent overload, hence optimizing grinding performance and reducing energy and grinding media consumption. Pebble flows can be analysed and uneconomic increments diverted to prevent recirculating flows consuming mill capacity unnecessarily. This also increases average feed grade.

Jan 1, 2016

By James F. Allan

"The Kipawa yttrium-zirconium prospect is located about 150 km south of Noranda, Quebec. Yttrium-zirconium mineralization occurs in an elongate, regionally metamorphosed and deformed peralkaline complex in the Grenville terrain. The mineralized zone, as defined by =.0.10% Y2O3, is 1300 m long and 10 m to 30 m wide. Zirconium content typically ranges from 0.50 to 1.20% ZrO2, The mineralized zone strikes northwest and dips 20 degrees to 35 degrees to the southwest. It occurs at the structural base of the peralkaline complex in syenite gneiss and calc-silicate rocks and is conformable with both the footwall contact of the complex, and the layering and gneissosity in the enclosing rocks. Minerals of economic interest are eudialyte (sodium-zirconium silicate), mosandrite (sodium-titanium silicate), britholite (calcium-silica phosphate), and a few other uncommon zirconium and titanium silicate minerals.The highest and most continuous yttrium grades occur in the upper part of the syenite gneiss unit in areas containing eudialyte, mosandrite and minor britholite. Yttrium also occurs in britholite in calc-silicate rocks and in mosandrite in syenitic rocks in the lower part of the syenite gneiss unit. Both the yttrium-bearing minerals and yttrium grades are erratic in the lower part of the unit. Zirconium is generally more uniformly distributed than yttrium. A peralkaline granite gneiss phase of the complex intrudes the syenite gneiss and possibly truncates it, and the mineralization, near the southern boundary of the mineralized zone.The mineralized zone is coincident with a radiometric anomaly and discontinuous yttrium and zirconium soil anomalies.More drilling and metallurgical studies will be required to determine the economic viability of the yttrium and zirconium mineralization at Kipawa."

Jan 1, 1992

By James F. Allan

"The Kipawa yttrium-zirconium prospect is located about 150 km south of Noranda, Quebec. Yttrium-zirconium mineralization occurs in an elongate, regionally metamorphosed and deformed peralkaline complex in the Grenville terrain. The mineralized zone, as defined by =.0.10% Y2O3, is 1300 m long and 10 m to 30 m wide. Zirconium content typically ranges from 0.50 to 1.20% ZrO2, The mineralized zone strikes northwest and dips 20 degrees to 35 degrees to the southwest. It occurs at the structural base of the peralkaline complex in syenite gneiss and calc-silicate rocks and is conformable with both the footwall contact of the complex, and the layering and gneissosity in the enclosing rocks. Minerals of economic interest are eudialyte (sodium-zirconium silicate), mosandrite (sodium-titanium silicate), britholite (calcium-silica phosphate), and a few other uncommon zirconium and titanium silicate minerals.The highest and most continuous yttrium grades occur in the upper part of the syenite gneiss unit in areas containing eudialyte, mosandrite and minor britholite. Yttrium also occurs in britholite in calc-silicate rocks and in mosandrite in syenitic rocks in the lower part of the syenite gneiss unit. Both the yttrium-bearing minerals and yttrium grades are erratic in the lower part of the unit. Zirconium is generally more uniformly distributed than yttrium. A peralkaline granite gneiss phase of the complex intrudes the syenite gneiss and possibly truncates it, and the mineralization, near the southern boundary of the mineralized zone.The mineralized zone is coincident with a radiometric anomaly and discontinuous yttrium and zirconium soil anomalies.More drilling and metallurgical studies will be required to determine the economic viability of the yttrium and zirconium mineralization at Kipawa."

Jan 1, 1992

By Kathy S. Kalenchuk

Damages have been observed in shafts, backfill infrastructure and the slick line at the Leeville Mine. Shaft damage (shearing and spalling of the concrete liner) is attributed to mine-induced rock mass deformations concentrated where regional faults intersect the shafts. Aggregate bin, mixer station and conveyor drive damage (shotcrete shearing, heave of concrete floor slabs and bending of a vertical steel beams) is attributed to rock mass squeezing induced by elevated magnitudes of the vertically orientated major principal stresses. Separation of the slick line has occurred do to extension of the stressshadowed rock mass immediately above the mined out areas. Three-dimensional numerical models have been developed and calibrated to simulated rock mass deformations with magnitudes similar to those believed to have produced the observed damages. By stepping through the mine sequence, models reproduce deformations at the same mining stage as when damage has occurred. Calibrated models have been used to forward project further damage over the remaining mine life.

Jun 1, 2012

By Gary Hawthorn

"Laboratory testing, by Lakefield Research determined that, in spite of the relatively high pyrite content of the Golden Rose (GR) orebody, it would respond well to gravity concentration followed by either direct cyanidation or cyanidation of a flotation concentrate.Economics favoured the former choice which became the adopted process flowsheet.During the latter stage of the feasibility study, the Dekalb 500 tpd copper flotation mill became available in the Highland Valley of British Columbia. This plant was purchased by Emerald Lake Resources, and was moved to the Golden Rose minesite.The crushing and grinding circuit were retained and the original flotation circuit was replaced with a 400 mtd gravity plus cyanidation circuit. The plant commissioning commenced in August 1987, and by early September was processing 300 tpd.HistoryThe Golden Rose Mine was operated by Cominco during the period 1935 to 1941 processing 146000 tons grading DAD oz/t Au at a rate of 110 tpd .The process flowsheet consisted of gravity plus amalgamation followed by cyanidation.Metallurgical TestingThe underground mining areas were below the level of Emerald Lake, and had flooded on abandonment in 1942.Samples for metallurgical testing were collected from exposed faces underground once the mine had been dewateredin 1984.In spite of the anticipated high pyrite content of the ore samples, it was apparent from the success of the previous operation that the pyrite did not interfere with the gold recovery.Laboratory testing, at Lakefield, determined that, from a technical perspective, two metallurgical options existed, as shown in Tables I and 2.Note that the very high pyrite content of the ore precluded the possible direct marketing of concentrate. The process flowsheet, therefore, had to contain a cyanidation circuit for the operation to succeed financially.Although the anticipated metallurgy was excellent with either option, the 2.1 % increase in gold recovery with the gravity plus cyanidation option made this the clear choice."

Jan 1, 1989

By John Mair

The Ilimaussaq Intrusive Complex in south Greenland is a layered alkaline igneous body that is predominantly comprised of agpaitic nepheline syenites. The Complex is now recognized as containing vast resources of uranium in polymetallic ores that are also strongly enriched in rare earth elements (REEs) and zinc. Uranium and REEs are dominantly hosted in phosphate minerals with a minor proportion hosted in zirconium silicate minerals. Equivalent ores are yet to be mined for uranium anywhere in the world; however, studies are well advanced in confirming a process route to economically extract uranium. The Ilimaussaq Complex is considered the world?s type-locality for agpaitic rocks. Formation of the complex is attributed to four successive pulses of magma. The first produced an augite syenite, which now forms a marginal shell. This was followed by intrusion of a sheet of peralkaline granite. The third and fourth stages make up the bulk of the intrusion and are peralkaline to hyper-agpaitic in composition. The third batch of magma differentiated to produce pulaskite, foyaite and naujaite. Stage four produced the kakortokites and lujavrites, which are the units of particular economic significance. Kakortokites are strongly enriched in zirconium, niobium and tantalum, whereas the lujavrites are strongly enriched in uranium, rare earth elements, fluorine and zinc. Lujavrites are vertically zoned with arfvedonsite (black) lujavrites grading downward into aegerine (green) lujavrites. The upper most portions of the black lujavrites contain uranium concentrations of greater than 450 ppm, which decreases toward green lujavrites where uranium concentrations rarely exceeds 200 ppm. Resources defined to date in accordance with the Australian JORC code include 282 M lbs of uranium oxide at a grade of 280 ppm. With scope for several other similar sized resources within complex, the overall potential resource is of immense global significance. Metallurgical studies to date indicate that uranium can be successfully extracted from black lujavrites via an alkaline pressure leach method. This involves selectively leaching uranium with solutions containing carbonate and bicarbonate at elevated temperature and pressure. Uranium can then be recovered by hydrogen reduction to create a uranium oxide product. There is also scope to beneficiate ores as uranium and REE?s are hosted in specific mineral groups. Phosphate minerals can be effectively concentrated by froth floatation and uranium-bearing silicate minerals can be concentrated by gravitational methods. Studies indicate that REEs can be extracted from the residue following the alkaline leach process by a dilute hydrochloric acid wash, with REEs then precipitated in the form of a REE concentrate.

Aug 1, 2010

By Michele L. Kimble

A fast-flow reactor mass spectrometer has been utilized to investigate the reactions of gas-phase gold cluster anions with CO and oxygen. Addition of CO to Aun - produces species of the form Au(CO)m -, where m = 2-5. However, CO does not bind to Au2 - or Au3 -. With oxygen addition in the cluster source, gold oxide species with both molecular and atomized oxygen are produced. The addition of carbon monoxide to these preoxidized gold cluster anions reveals that select species with 1, 2, and 3 gold atoms participate in the oxidation reaction to produce CO2. Bimolecular rate constants for the reactions between these species and CO are also discussed.

Oct 1, 2003

By X. Cao, X. -G. Chen, K. Liu

Due to the detrimental effect of platelet iron-rich intermetallics on mechanical properties (particularly ductility) in cast alloys, it has been essential to transform these phases into Chinese script morphology. In the present work, the effects of Mn and/or Si addition and cooling rate on the phase transformation of the iron-rich intermetallics in 206 cast alloys with different Fe contents ranging from 0.15 % to 0.5 % were systematically investigated. The results obtained showed that platelet ß-Fe and Al3(FeMn), Chinese script a-Fe, Alm(FeMn) and Al6(FeMn) can be observed in the 206 cast alloys, depending on the Fe, Mn and Si contents as well as the cooling rate. It was found that the addition of either Mn or Si favors the formation of Chinese script iron-rich intermetallics but inhibits the precipitation of the platelet phases. In addition, the combined addition of both Mn and Si has a synergistic effect on the phase transformation. Furthermore, there exists a critical cooling rate to effectively suppress the formation of platelet iron-rich intermetallics for a given alloy. The threshold cooling rate decreases with increasing Fe, Mn and Si contents. Casting process maps are established to correlate the intermetallics precipitated with alloy chemistry and cooling rate for 206 cast alloys containing various Fe levels.

Jan 1, 2014

By Mario A. Morin

Over the years, several sources have stressed the need to better integrate the underground mine design and planning processes. The belief is that with better integration, better designs and plans will result - designs that are ?optimized?. Some researchers have focused their efforts on data integration, others have looked at closing the loop between production control & monitoring with mine planning & scheduling. In spite of all these efforts, fully integrated applications combining geological modeling, stope design and geomechanics, mine planning and scheduling, rock extraction and material handling system design, mine support systems, economic analysis with production control do not yet exist for the underground hard rock mining industry. There are several likely explanations - some economic, some technical. It is certain that the design and planning processes are interrelated and interdependent and thus are extremely complex to describe and understand. The mining engineer has an appreciation of the complexities involved - but how does he convey this knowledge to a programming team responsible for developing an integrated design & planning system. This paper will focus on software engineering methods, and other possible approaches, to describe and manage the complexities inherent in the underground mine design and planning process and the development of an integrated computerized system.

May 1, 2001

By R. A. L. Drew, F. Edelmann

Brazing is a low-cost process used extensively in the manufacturing and repair of aircraft gas turbine engines. Components within the compressor stage of the engine experience relatively low temperatures (600-700°C), therefore joints of stainless steels are typically employed. In such joints, a Pd-Ni-Cr-Si-B (PalNiCroTM) brazing alloy is used as a sealant, however brazing procedures are not well understood. The wetting behavior of PalNiCroTM on AISI 347 was evaluated with respect to contact angle. A microstructural evaluation was carried out with variable joint clearances. Microhardness profiles were performed to investigate the presence of hard secondary phases, which were later confirmed by electron microscopy. The results indicated an equilibrium contact angle of 10° within 100 seconds. The average microhardness of the braze layer and base metal were approximately 550 and 205 VHN, respectively. At the interface, a diffusion zone was present containing carbides and borides.

Jan 1, 2004

Presentation Overview Corporate Overview Kutcho Project History Exploration Development Permitting Capstone -Pursuit of Value Building a mid-tier copper producer focused in the Americas Two operating copper mines; Cozamin& Mintomines High grade and low cost 2010 forecast: 80-85 million pounds of copper in concentrates Total Cash Costs* of ~US$1.10/lb to US$1.20/lb of payable copper produced Significant by-products of gold, silver, lead & zinc Growth potential Further expansions at existing Cozamin& Mintomines High grade copper development: Kutcho project, BC Investments in Nevada Copper & Silver Wheaton 100% North American assets Low risk ?Canada & Mexico ?Conventional operations

Oct 1, 2010

By C. J. Kerr

"A recent information sheet from the Mining Health and Safety Branch of the Ontario Ministry of Labour was sent to all Ministry inspectors and engineers. The subject title was' 'Two Brakes on a Hoist Carrying Persons"" and it quotes mining regulation 699, sub-section 206(i):No hoist shall be used for the transporting of persons unless it has a braking system consisting of at least two sets of mechanical brakes to stop and hold the drum for the shaft conveyance transporting the persons.The intent of the regulation is that each of these brakes is to be set so that, individually, they can safely stop the drum carrying persons and also hold the drum without movement with the maximum manload.This can be achieved in the following ways: Single Drum Hoist-one brake on each side of the drum, one brake on the drum, one brake on the pinion shaft, where disc brakes are used two separate disc brake assemblies on the disc. Double Drum Hoist, brakes on companion drum can serve as backup brake only pinion brake with one drum unclutched.Friction Hoist, one brake on each side of drum As new hoists can be manufactured easily with a two-brake system, attention will be focused on retrofitting pinion brakes to older hoists.A brake mounted on a pinion shaft is designed purely as an emergency brake in the event of main brake failure , controls malfunction, and power loss."

Jan 1, 1989

By Finley A. Campbell

"Nickel-copper sulphide deposits associated with basic rocks in the Quill Greek area and the White River area in the Yukon Territory have been studied and compared from the view-point of their general geology, structural geology, and the mineralogy of the ores. The relative amounts of the major constituents, magnesium, iron and calcium, and the minor constituents, nickel, cobalt and chromium have been determined spectrographically for two cross sections of the basic rocks at Quill Creek and one at White River. These data, along with petrologic and field evidence, were used to determine the sill and dyke-like character and nature of the basic intrusions. Loss on ignition is employed as a measure of the degree of serpentinization. The distribution determined shows that the serpentinization does not appear to have greatly influenced the inferred original distribution and lithophile associations of magnesium and nickel. The cobalt content may have been altered.The nickel content of the serpentinized peridotites ranges from an average of 0.36 per cent in one section to an average of 0.24 per cent in each of the other two sections studied. The cobalt averages 0.0038 per cent in the samples from the two Quill Creek sections and averages 0.0042 per cent at White River. These results have been compared with other available data.The sulphide ores are later than both the peridotite and gabbroic rocks and may be co-magmatic with them. There is no evidence in these areas to support an origin by lateral secretion; on the contrary, the alteration associated with the ores, the mineralogy and spatial relationship to basic and ultrabasic rocks, indicate the ores are derived from a basic magma."

Jan 1, 1960

By D. J. Parker, G. B. Tupper, I. Govender

Positron-Emission-Particle-Tracking (PEPT) has enabled the non-invasive observation of charge and slurry transport in model mills under operational conditions. We use high quality PEPT data to infer that the charge motion can be effectively described by a non-Newtonian granular fluid. An improved theory for slurry transport, including inertial effects, is presented.

Jan 1, 2012

By R. A. Leveille, M. D. Doggett

"Economic returns for the copper industry have been assessed by building cash flow models for each of the 100 new mines brought into production over the past 20 years. Ninety-one of the 100 new mines returned the assumed 8% cost of capital and generated a positive net present value (NPV) at the development decision point. Economic criteria for individual mines are highly variable with NPV ranging from -$111 million (-$111M) to +$3850M (all money values are presented in United States dollars) and internal rate of return (IRR) ranging from -8% to +95%. The copper industry collectively would generate approximately $39 billion dollars in NPV through the development of the 100 new mines.The returns to exploration ($174M per deposit) were measured by deducting the cost of exploration per deposit ($221M) from the returns to development per deposit ($395M). Overall, the copper business has provided positive returns to exploration. However, the variability in returns across deposits means that only 41 of the 100 new mines can carry the average cost of exploration. The long lead times and high costs associated with exploration result in only those deposits with large amounts of contained copper being able to cover the average finding cost of the industry.The returns to development and exploration are shown to be highly sensitive to the cost of capital and metal price assumptions. With respect to deposit type, porphyry deposits are both larger (NPV) and exhibit lower profitability (IRR) than the nonporphyry deposits. On a geographic basis, returns to development and exploration are higher in Chile than elsewhere, reflecting the larger average deposit size and lower average exploration cost per deposit."

Jan 1, 2009

By K. J. Brouwer, J. P. Haile

"Construction of the first stage of the tailings disposal facility for the Montana Tunnels Project was completed in October 1986. The project is located 37 km south of Helena, Montana, and involves mining of42 million tons of weathered diatreme are at a rate or 13 500 tpd to produce a gold/silver dore, as well as lead and zinc concentrates. The tailings disposal facility for the project includes a fully drained tailings impoundment for storage of the tailings solids, and a process waterpond for storage of all decanted water prior to recyling to the mill. The over-all facility is designed to achieve the basic objectives ofminimizing seepage to the environment in the short- and longterm, and achieving a fully drained stable tailings mass suitable for immediate reclamation on completion of mining. Specific features of the design include a soil bentonite seal and drainage system within the tailings basin, a free draining embankment with a design flow-through capacity of 4000 US gpm and an ultimate height of 230 ft (70 m), and a soil bentonite lined make-up water pond with a capacity of 420 acre-feet (530 000 m'). The tailings will be discharged in a rotational sequence through multiple spigot offtakes to achieve a thin-layer low energy laminar flow. This 'sub-aerial' deposition results in higher stored densities and maximizes liquid-solid separation on the tailings beaches. The over-all design played a major role in the successful permitting of the project, and was significantly cheaper than a conventional wet disposal system, with overall unit costs for tailings disposal of less than US$0.36 per ton.This paper outlines the site characteristics and the tailings material properties and their influence on the design. Extensive use was made of naturally occurring free draining materials as well as bentonite modified soil liners within the tailings basin, embankment and retention ponds. General construction procedures for the various components are described, as well as on-going construction requirements utilizing materials from the open pit. Finally, the over-all costs and unit costs for tailings disposal are presented."

Jan 1, 1988

By S. Afshar, C. Allaire

Several studied have recently shown that the use of non-wetting additives is not always a sufficient solution to improve the corrosion resistance of refractories against molten aluminum. Once in contact with liquid aluminum, the coarse aluminosilicate aggregates, which do not benefit from the protective effect of non-wetting additives in the matrix, may be corroded. In some cases, the corrosion of aggregates, especially those containing a significant amount of free silica and/or alkalis, promotes corrosion in the surrounding matrix. The present work explores the possibility to protect the poor corrosion resistant aggregates via a lining procedure. A slip casting method, using either alumina or celsian-like composition based slurries, has been applied for lining of a series of aggregates. The results from this study show that such linings may prevent efficiently the corrosion of aluminosilicate aggregates. This work also analyzes the effects of firing temperature and lining quality on the corrosion behavior of aggregates

Jan 1, 2004

By Andrew Kerr

Overview of Presentation ? Introduction ? An historical context: From 1866 to the 21st century. ? Geological framework for iron ore in the region known as the ?Labrador Trough?. ? Producing iron-ore deposits of the Labrador City ? Wabush area, and near-future production from the Schefferville area. ? Exploration projects representing potential future production?.or expansion of the district. ? Some concluding remarks???

May 1, 2011

By P. A. Mascaró, N. Chacon, A. A. Cecchi

"This document shows the development of a system called the “On-line charge level determination in SAG mills” (abbreviated as Jc). The Jc variable has certainly been difficult to measure due to the relevant number of factors and variables that affect the grinding phenomena inside semi autogenous (SAG) mills. To assess the feasibility stage of the proposed system, it was necessary to carry out two tests in different sized SAG mills, 38´ × 22´ and 36´ × 15´, respectively. In each test, the system was configured with a battery of sensors of the following types: (1) strain gauge, (2) accelerometer, and (3) gyroscope. The first step involved for charge level determinations was to determine kidney foot and shoulder by means of a study of the energy-impacts on shell structures. The second step consisted of correlating the measured grinding operational variables with the actual charge levels obtained from SAG mill crash stops. This system development is extremely useful and relevant for providing approximations about mass balances inside SAG mills. It will be a suitable tool for explaining “tonnes per hour” variations and determining optimal points under various operating conditions.INTRODUCTIONThere has been a growing necessity for technologies capable of obtaining “on-line data” of the main comminution variables in order to increase throughput. Computer systems have taken an important role in providing important solutions by means of processing on-line device signals (commonly referred to as monitoring). In semi autogenous (SAG) milling, there are many examples of monitoring devices that allow the operational staff to obtain detailed information both mechanically and electronically inside a grinding circuit. In this context, a new technology has been developed to obtain “Jc total charge (%) online” in two different SAG mills called Vibro-Energy® System.As part of the analysis performed by JKsimMet® the Jb/Jc was estimated because it has an important impact on SAG mill throughput. Different scenarios were simulated and contrasted at various theoretical Jb/Jc values in a baseline circuit (Figure 1)."

Jan 1, 2016

By Mark Richards

Highland Valley Copper is a large, open-pit copper mine in the southern interior of British Columbia. Reclamation has been in progress on the site since 1987. Some 6,300 hectares will have been disturbed at the end of the mine?s life, the majority of which will eventually be reclaimed. The establishment of vegetation and the development of a self-sustaining vegetative cover are the central components of the mine?s reclamation plan. The present vegetation-monitoring program for the reclaimed area represents a significant commitment of resources and only addresses a small portion of the site each year. In an effort to expand the area surveyed while improving the efficiency of the monitoring, the use of remote sensing is being investigated. Airborne multispectral imagery was acquired in the summer of 2001, and the results of the multispectral classification were compared to ground observations made during the routine 2000 and 2001 monitoring program. A thematic map with 17 vegetation classes was produced. Within the vegetation classes, there was a strong spectral separation between ? dry grasses? and ?legumes? with further separation according to their density. Green biomass could also be quantified remotely across a wide variety of vegetation types. During summer 2002, further aerial imagery was acquired in combination with a targeted ground-truthing program to determine characteristic vegetation types associated with recognized spectral signatures, which can be used in a supervised classification. It is anticipated that after some fine-tuning, it will be possible to shift the ground-sampling effort from areas where the aerial classification confidence is high to more complex areas.

May 1, 2003