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By Andrew Thrift

Overview ? Problem ? Research question ? Literature review ? Methodology ? Results ? Discussion and recommendations ? New developments Problem ? Increasingly higher expectations ? Inadequate consultation leads to conflict rather than collaboration ? Consultation practice is often weak on decision-making ? Influence of consultation on planning is Unclear Research question ? Are Structured Decision Processes (based on decision analysis) an effective methodology for involving stakeholders in consultative decisionmaking in the mining industry?

May 1, 2006

By Charlie Graham

Our Approach ? Industry Trends ? New Forces at Work in Mining ? Deep Mining ? Energy projects ? Air power ? Hydraulics ? Electric alternatives ? Drilling ? Productivity ? Conclusions ? Transportation ? References

Oct 1, 2010

By S. Ghafarnejad Parto, Å. Rasmuson, A. Fredriksson, M. Mohammadi, K. M. Forsberg, J. Martinez De La Cruz

The present study aims at recovering rare earth elements (REE) in conjunction with the production of fertilizers from an apatite concentrate. Apatite is one of the REE rich minerals ending up in the tailings pond when Luossarvaara-Kiirunavaara AB (LKAB) in Sweden processes Malmberget’s iron ore deposit. Leaching with nitric acid, hydrochloric acid, and sulphuric acid respectively have been studied. The nitric acid route was chosen for further investigations and the optimum acid concentration for leaching of the REE were determined. The leached REE are recovered by solvent extraction using di-(2-ethylhexyl) phosphoric acid (D2EHPA) and 2-ethylhexylphosphonic acid-mono-2-ethylhexyl ester (EHEHPA).

Jan 1, 2014

By Ron Ferris

The Westinghouse Temptifier TM, using heat pump principles, recovers lowgrade waste heat in the 600P to 1600P temperature range and amplifies it to usable levels of up to 2200P. Coefficients of performance (C.P.D.) normally encountered are from 3.0 to 6.0, with capacities from 200,000 to 10 million Btu/hr.

Jan 1, 1979

By G. Tairova, J. Ioffe

Arsenic, selenium and mercury species are common contaminants in mining aqueous streams and present significant environmental and health problems. The objective of this project is to investigate methods to lower the concentrations of these elements in mining aqueous streams. A new composite media for removal of these elements of concern from mining effluents was developed. The results of bench scale and pilot plant experiments, using the media, indicated removal of arsenic, selenium, mercury and other elements of concern below detection limits.

Jan 1, 2014

By Scott Hommema

? Bitumen in the oil sand averages Bitumen 12 wt%; water makes up 4 wt% ? Imperial Oil (operator) and ExxonMobil developing Kearl Leases #6, 36, 87 (~200 sq. km) ? Target resource > 4 Billion Barrels ? 3 Phase development, ~100 kbd per phase High-quality resource ? Surface mineable bitumen ? Average properties (full lease) ? TV:BIP < 8 ? Grade > 12 wt% bitumen ? Ore thickness of 40 m ? Overburden thickness of 20 m Status ? Phase 1 ? Front end engineering and design underway ? Detailed engineering to start 2008

May 1, 2008

By E. Sigal

Overview ?Intrinsik has completed several wide area HHRA and ERA studies of mining and smelting communities ?Several ?Lessons Learned? ?Key areas related to: ?Study Design ?Data Quality ?Bioaccessibility ?Speciation ?Weight-of-Evidence Approaches ?Advances in Ecological Risk Assessment Techniques

May 1, 2009

By Osvaldo A. Bascur

Industrial complexes rely on measurements of flow rates, qualities, and concentrations for monitoring and optimizing their operation. Corporations use the data from the various sensors and measurements to make business decisions, which affect the profitability of the operation. However, gross errors, due to a variety of reasons like faulty sensors, bad instrument calibration, or incorrect process models may corrupt the actionable information supplied to operations, quality managers, and maintenance personnel. The solution is to use the sophisticated new tools to model the process, sift through the available data to locate the gross errors, and use statistical data reconciliation to validate the sensors and instruments. In this way the data are unified to give the most accurate plant information for use by the monitoring and decision making processes. Most mining and metallurgical plants use predictive maintenance policies based on statistical analysis and special techniques, like vibration analysis, and oil and lube analysis for critical equipment. Process control strategies are installed in several metallurgical sites. All of these depend on reliable and accurate data. The data unification methods validate the individual measurements by using the concept of balances and statistical techniques where each instrument is no longer independent of the other measurements in the facility. This paper refers to the data unification and analysis methods required for profitable plant operations. Continuous improvement and monitoring of the measurement system at the plant and analysis of the reconciled data provide the best information for the decision-making process. On-line gross error detection and elimination methods are required to ensure efficient evaluation of process performance and process optimization. An open discussion of the new methods for gross error detection and data unification will be presented.

May 1, 2001

By Marcel M. Djivre

The paper will outline the destructive test methods and test procedures including the evaluation criteria currently used at the Materials Testing Laboratory (MTL), Sudbury, Ontario, Canada, a laboratory approved by the Ontario Minister of Labour for the purpose of testing or examining mine shaft ropes or other hoisting appliances. For the evaluation of the mechanical properties of rope samples used in "ultra-deep" single-lift shafts, additional discard criteria used in Ontario, Quebec and South Africa shall be presented. Most of the methods and test procedures currently used at MTL can also be found in the current CSA G4-00 Standard, Steel Wire Rope for General Purpose and for Mine Hoisting and Mine Haulage, published in November 2000. In this latest or sixth edition of CSA Standard G4-00, a new Clause 14 has been added outlining the requirements for in-service destructive testing of steel wire ropes for mine hoisting applications. The CSA G4-00 Standard is also intended for the manufacturing of new ropes, and includes requirements for raw materials and construction features for round strand and flattened strand rope, and locked coil rope in bright and galvanized finish. To-date the Ontario Mining Regulations require only that destructive test of new ropes be performed in accordance with CSA Standard G4-00, but does not require conformity to the Standard, and on the other hand the inservice wire ropes are required to be tested in accordance with CSA G4 and thus require conformity. The author recommends that the Ontario Mining Regulations (and regulations of other mining jurisdictions) be improved in order to ensure quality control in the manufacturing of wire ropes destined for mines in Ontario (and Canada). Also, the author recommends the revision of the CSA G4-00 Standard by the technical committee in order to address manufacturer?s concerns with respect to compliance, and harmonize the Standard with Internationally recognized Standards.

Apr 1, 2005

By D. Virely, M. Gasc-Barbier, J. Guittard

"The valleys of the Dordogne and the Vézère (France) have been inhabited since prehistoric times, as evidenced by the famous site of Lascaux. A few miles away, the village of La Roque-Gageac is also a very popular tourist destination (about 1.5 million tourists per year): The village is sandwiched between a massive limestone cliff and the Dordogne river. The collapse of a cave roof high above the village in January 2010 led us to characterize instability together for the cave and the whole cliff and propose a adapted instrumentation to monitor the fracture openings in the rock mass that are linked to climatic variations. Measurements have been going on and been recorded for nearly 4 years. They point out the role of thermal stress fatigue in the breakdown of the rock mass. In this paper we describe the site under study, the instrumentation and its main results. INTRODUCTIONThe phenomenon of thermal fatigue has been very little studied as far as rocks are concerned, whereas it is rather well characterized for other types of materials: Elsevier published a journal dedicated to fatigue (International Journal of fatigue). In the case of rocks, thermal phenomena and their impacts on mechanical behavior have been analyzed from a micro-structural point of view, and it is now well-known that an increase in temperature causes a dilatation of crystals (Arnould et al., 2004; Berest & Weber, 1998). This dilatation may lead to the development of inter-granular traction and compression stresses, and if those stresses are greater than fracture strength, inter-granular and intra-granular cracks may take place. On the other hand, the fatigue phenomenon (cyclic repetition of a temperature variation which is less extreme than the one that may lead to this inter-granular or intra-granular fracture) is a phenomenon which has not been much studied.The principal studies on thermal fatigue on rocks come mainly from the field of geomorphology, particularly in connection with the analysis of the evolutions of past climate that can explain the present shapes of those landforms: those studies remained essentially qualitative and not quantitative. Le Ber & Oter Duthoit (1987) proposed a thermal and thermodynamic approach to analyse the disaggregation of rock masses. This analysis is dedicated to the study of paleoclimates and was implemented to better understand the formation of slope deposits in order to propose transfer models permitting the reconstruction of the climactic conditions contemporary to their appearance. Since deterioration in the cliff only appears after several cycles, it means that it is a gradual and irreversible deterioration which leads to an increase of the « disorder ». Seen from a macroscopic system point of view, this irreversible evolution is quantified by the internal creation of entropy."

Jan 1, 2015

By A. J. W. Law

"This paper deals with the organization of the central office technical areas and the role played during the feasibility studies, construction and operating phases of Les Mines Selbaie.HistoryThe Engineering Department was originally formed as a part of the Exploration Department, to examine the feasibility of advanced exploration prospects being brought to the company. In 1968, with the discovery of the South Bay property in northwestern Ontario, the department became part of a Mining Division and was expanded, so that it could provide more advanced mine feasibility studies, control of construction engineering and procurement and initial mine design. As is generally the case, the mine design function was handled with in-house capability, while plant, mill and const ruction functions used outside consultants.The 1974 discovery of the Selbaie deposits, started a period o f growth in the capabilities o f the department. The complex nature of these deposits, required that skills were added in the mining, metallurgical and plant areas. During the early feasibility study period these skills were provided by the engineering company of the parent group, but when it was realized that production from the deposits was likely, permanent staff was added."

Jan 1, 1990

By M. E. Stutt, R. H. Rehder

"The mining industry is taking advantage of the increased performance resulting from the use of variable speed A C drives for large motors. This technology provides increased efficiency under the variable speed and torque requirements of such drives as mine hoists, conveyors, and air moving equipment. The technology does introduce voltage spikes on the voltage wave form that stress the insulation system to a greater degree than would occur with a constant voltage source. These voltage spikes must be considered in the design of the insulation system used for these motors.BackgroundHistorically the insulation systems for large AC motors were designed to withstand with reasonable life the voltage stresses of a 60 Hz constant sinusoidal voltage. One of the design tests is a voltage endurance test that requires the application of a 60 Hz voltage from conductor to ground equal to four to five times normal and establishing a time to failure. These higher than normal voltages accelerate the normal aging process by causing extensive partial discharge activity (corona) within the insulation system and the time to failure is a relative indication of insulation life.In addition to the voltage endurance test at 60 Hz, the individual coils are subjected to a surge voltage test to establish the withstand capability of the turn to turn insulation under switching surge conditions. The surge voltage is a fast rise time, 0.2 microsecond to crest value, voltage spike that can be caused by a circuit breaker or contactor closing operation. These voltage spikes can have a crest value of greater than 3.5 times the normal line to ground crest voltage of the normal 60 Hz power supply. The standard withstand test value is thus 3.5 times normal line to ground voltage. Because the voltage surges or spikes occur mainly during start and stop switching conditions, voltage endurance under these conditions has not been a major factor in insulation system design."

Jan 1, 1995

By O. Lashkari

Swirled Enthalpy Equilibration Device (SEED) is a new patented Slurry-on-Demand, SoD, processing route. The semi-solid slug preparation is carried out by off-center swirling of aluminum melt in a metallic mould. As part of the current research program on the semi¬solid processing of aluminum alloys, the morphological evolution of 356 aluminum foundry alloy microstructure is reported here. Semi-solid slugs were prepared using two different pouring temperatures of 645°C and 695°C respectively. Morphological evolution of the semi-solid microstructure was characterized using image analysis through measuring of primary a-Al particle size, number density, aspect ratio and sphericity. The possible relationships between microstructural features and process parameters were also investigated. The current report covers the effect of pouring temperature on the morphology of primary a-Al dendrites and attempts are made to explain the differences between the predicted percentage primary a-Al phase and those of the actual values in the as-cast slugs.

Jan 1, 2004

By T. A. Apelt, B. J. Elliot

"In September 1993, the flash furnace at Kalgoorlie Nickel Smelter, KNS, was brought off line after almost 12 years of operation. This is a record campaign life for a flash furnace. The furnace was&apos; totally rebuilt and the capacity of the plant increased from 540 000 tpo to 750 000 tpa of concentrate throughput. The throughput increase was&apos; achieved through the construction of a 525 t/day oxygen plant and upgrading of various plant ancillaries. A number of significant design modifications were also built into the flash furnace and oxygen enrichment was implemented in the operation of the Peirce-Smith converters.This paper discusses the rebuilding of the flash furnace and design modifications made to furnace equipment and ancillary plant. Some preliminary post-startup operating data are presented.IntroductionIn September 1993, Campaign 6 of the flash furnace was concluded and the furnace brought off line for rebuilding. The campaign length was almost 12 years and set a new record for campaign length. Planning for the rebuild took place over the last five years of the campaign. A number of modifications to the design of the furnace and the ancillary plant were planned to coincide with the furnace rebuild. The furnace was rebuilt and recommissioned in 70 days. The increased plant capacity of 750000 tpa has been achieved by the construction of a 525 t/day oxygen plant and modifications made to ancillary plant which centred around increased p~ control, efficiency and hygiene. This paper examines the development and implementation of the modifications made to the furnace and ancillary plant. Preliminary post-shutdown performance data are presented."

Jan 1, 1995

By David L. Huston, Wouter Bleeker, Bruce E. Taylor, Ron Cook, Bob Stewart, Elizabeth R. Koopman

"Abstract—Detailed oxygen isotope mapping of rhyolites in and around the Kidd Creek mine indicates that the orebodies are associated with relatively low (<12‰) whole rock values that extend up to 200 m laterally from ore. The zone of low d18O values is overlain stratigraphically by a carapace of higher (>13‰) values that extends up to 1.5 km laterally from and 300 m to 500 m above ore. Immediately above the stratigraphically highest orebody this carapace is cut by a zone of lower d18O values extending from the ore zone. Zones of higher d18O values also occur in massive rhyolite bodies that occur in the footwall of the orebodies.The zone of low d18O values partly coincides with a Na2O depletion anomaly associated with hydrothermal alteration, except that the Na2O depletion anomaly has a greater lateral extent, and the low d18O anomaly extends farther into the stratigraphic hanging wall. These data suggest that d18O mapping may detect hanging wall alteration above massive sulfide bodies more effectively than conventional lithogeochemistry. Zones of high d18O values, which define zones through which large quantities of low-temperature hydrothermal fluids have passed, may also have usefulness in exploration.Oxygen isotope variations at Kidd Creek record three stages of a hydrothermal system that evolved in temperature with time, as follows: (1) an early, low-temperature event that produced rocks with high d18O values, (2) a high-temperature event that produced rocks with lower d18O values, and (3) a later, low-temperature event that also produced rocks with high d18O values. The high d18O signature of the massive rhyolite was recorded during early-stage, low-temperature (<200°C) alteration, and was probably preserved owing to decreases in permeability associated with low-temperature silicification. The low d18O signature of cherty breccia and chloritite was recorded during the thermal peak at >300°C. High d18O values in the carapace above the deposit were recorded as the hydrothermal system waned."

Jan 1, 1995

By M. Mahdi, L. So, A. MacMillan, D. Metcalfe, J. Woloshyn, D. Sauter, N. Uys, JP. Janse van Rensburg

For city smelters, with limited real estate, efficient slag cleaning furnaces followed by water granulation to produce an iron silicate product is the preferred process approach. Water granulation, however, consumes large volumes of water and requires high maintenance due to abrasive slag/water slurries. Air granulation offers an alternative to water granulation, which eliminates water use and has low maintenance requirements. Although full-scale operation has not been implemented for copper slags, full-scale operation for platinum group metal (PGM) converter slag has been implemented. A review of full-scale air granulation performance for PGM converter slag is provided. Based on PGM converter slag granulation performance, parallels to copper slag granulation are drawn and full-scale operation for copper slag is modelled using computational fluid dynamics (CFD). INTRODUCTION Typical slag management practices in the copper industry include dumping, slow air cooling, and water granulation, as shown in Figure 1. Dumping is the most commonly used slag handling method for most metal production plants, but presents challenges including the requirement for a large slag pit, requirement for expensive/high-maintenance “hot” mobile equipment, risks associated with transportation of molten slag, and no value recovery from slag as a sellable by-product or from slag as a source of heat.

Jan 1, 2019

By David L. Huston, Wouter Bleeker, Bruce E. Taylor, Ron Cook, Bob Stewart, Elizabeth R. Koopman

"Abstract-Detailed oxygen isotope mapping of rhyolites in and around the Kidd Creek mine indicates that the orebodies are associated with relatively low (<12‰) whole rock values that extend up to 200 m laterally from ore. The zone of low d18O values is overlain stratigraphically by a carapace of higher (>13‰) values that extends up to 1.5 km laterally from and 300 m to 500 m above ore. Immediately above the stratigraphically highest orebody this carapace is cut by a zone of lower d18O values extending from the ore zone. Zones of higher d18O values also occur in massive rhyolite bodies that occur in the footwall of the orebodies.The zone of low d18O values partly coincides with a Na2O depletion anomaly associated with hydrothermal alteration, except that the Na2O depletion anomaly has a greater lateral extent, and the low d18O anomaly extends farther into the stratigraphic hanging wall. These data suggest that d18O mapping may detect hanging wall alteration above massive sulfide bodies more effectively than conventional lithogeochemistry. Zones of high d18O values, which define zones through which large quantities of low-temperature hydrothermal fluids have passed, may also have usefulness in exploration.Oxygen isotope variations at Kidd Creek record three stages of a hydrothermal system that evolved in temperature with time, as follows: (1) an early, low-temperature event that produced rocks with high d18O values, (2) a high-temperature event that produced rocks with lower d18O values, and (3) a later, low-temperature event that also produced rocks with high d18O values. The high d18O sig- nature of the massive rhyolite was recorded during early-stage, low-temperature (<200°C) alteration, and was probably preserved owing to decreases in permeability associated with low-temperature silicification. The low d18O signature of cherty breccia and chloritite was recorded during the thermal peak at >300°C. High d18O values in the carapace above the deposit were recorded as the hydrothermal system waned."

Jan 1, 1995

By P. J. van Staden

Several differences exist between the columns used for laboratory simulations of heap leaching and commercial heaps. Column walls support part of the weight of the ore and restrict the particle packing arrangements. Columns are typically of a diameter that is smaller than the dripper spacing to be used on the commercial heaps. The stacking practices that cause segregation and stratification on heaps are absent from columns. Intuitively, these physical differences would be expected to be the reasons behind the observed differences between column and heap leaching performance. But how can they be quantified, and what is the magnitude of the differences? Could some of these differences be built into column leaching experiments in order to better simulate commercial-scale heap leaching performance to ease the scale-up calculations from column leaching data? Alternatively, could heap construction practices be improved so that the ideal performance obtained in columns could be emulated on heaps? Data from a few heap leaching cases studies that permit direct comparisons between column and heap leaching performance is analysed, to reveal the extent of the differences in resistance to mass transfer. Discussion is provided on the implications for column and heap leaching practice, and for scale-up design procedures. INTRODUCTION Differences have been known to exist between leaching performance observed in laboratory columns and that of commercial-scale heaps. Both the heap leaching kinetics and finally achievable extent of extraction are generally found to be inferior in heaps compared to that achieved in columns. Heap leaching design engineers extrapolate the anticipated heap leaching performance by multiplying the time-axis of a column-leaching curve by a factor of about 2 and the extraction-axis by a factor of about 0.8, as explained by Jansen and Taylor (2002), Scheffel (2002), John (2011) and Scheffel, Guzmán, and Dreier (2016). The procedure is illustrated in Figure 1 by means of a hypothetical example. The solid line represents the leaching performance observed in a laboratory column, and the dashed line represents the anticipated leaching performance of a heap, extrapolated from the column leaching data using these empirical scale-up factors.

Jan 1, 2019

By Charles Graham

For hundreds of years the standard vertical mine shaft was rectangular shaped and timber lined. There are many advantages to rectangular shafts but as mines became deeper the circular shaft became more popular. The chief advantages of circular, concrete lined shafts are their ability to resist lateral pressure and they offer less resistance to ventilation air. A number of elliptical shafts have been sunk in an attempt to realize the advantages of both the rectangular and the circular shaft. A concrete lined elliptical shaft provides better space utilization than a circular shaft, would allow for shaft sinking with two double drum hoists, as well as concurrent level development. The design also makes one sided stations possible and provides for a simple headframe design.

Feb 1, 2008

In the last 30 years numerous mining plants have been developed in North America but only a handful of these have required freezing the area where the shaft was sunk. The most recent mine shaft to be sunk using this technique is located on an island off the coast of Louisiana. The project required the input and skills of numerous people in several companies, including the owner, engineers and contractors. The Cote Blanche installation is one of several mines in the area which extract salt from a dome which extends under the Gulf of Mexico. The geology of this area is, however, markedly different from others in the region because there is approximately 460 ft of water logged soil above the salt dome. Because it is not possible to sink a shaft in ground that is this soft, the overburden where the shaft is located must be frozen before excavation can take place. The Cote Blanche mine is a producing facility which was built in 1958 by the Carey Salt Company. The original facility included a 14 ft diameter production shaft and a 7 ft-8 in diameter service/ventilation/escape shaft. This system was installed by The Cementation Company. In 1996 the owner decided to improve both the mine ventilation and production hoisting system by installing a third shaft. This shaft would be designed to extract 650 tons per hour from a depth of 1600 ft and provide 500,000 cfm of ventilation to the mine at a maxium design pressure of 4 in WG. These parameters resulted in a requirement for a 16 ft finished inside diameter concrete lined shaft and a headframe designed as a pressure bulkhead. Because the mine would operate from one level only, the most efficient hoisting system for the application was determined to be a ground mounted koepe running on rope guides. With these criteria fixed Cote Blanche embarked on a program which would see construction start in June 1998 with the first salt produced in February 2001 at a cost of $US18M. The major players in the design and construction were G.L. Tiley & Associates Ltd., BLM Bharti Engineering, Freezewall Inc., Phillips Mining, Geotechnical and Grouting Inc., Don Hart Consulting and Dynatec International.

May 1, 2002