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The extractive industry has the potential to impact the health and well-being of workers, families and surrounding communities. In the current environment of social performance, project planning considers that activities should be conducted in the best environmentally, socially and economically acceptable way across the development cycle (i.e. from exploration ? post-closure). In this context, health impacts of mining can be mapped and extend over the Life of the Community and can encompass worker injury and disease, exposure to communicable and non-communicable diseases, and health outcomes specific to family and community health and well-being outside the fence. To contribute to an emerging field focused on Health and the Extractive Industry, this paper reviews and compares health activities extracted from social and environmental reports published by selected major mining, oil and gas companies with operations in Australia and Canada. The objective of this review is to map corporate approaches to public health management across our previously developed Life-of-Mine within Life-of-Community (LOMLOC) framework in order to identify and compare trends and behaviour in corporate health investments across the project cycle, as well as identify the level of prevention targeted by this investment activity (i.e. primary, secondary and tertiary prevention of detrimental health impact). With the extractive industry facing ongoing rapid growth worldwide, this paper provides preliminary comparative information about corporate health spending by some companies in Australia and Canada. This information serves as a resource for minerals industry managers, civil society and regulators regarding current health management approaches in this sector.

Aug 1, 2013

By Guocheng Pan

"Although many factors play roles in the estimation of recoverable reserves, smoothing effect and conditional bias are considered major geostatistical issues in the estimation. This paper introduces measures for smoothing effect and conditional bias, and provides insights into their relation to the estimation of recoverable reserves. Both smoothing effect and conditional bias are intrinsic to the information effect and kriging estimators. For a given level of drilling information, however, it is possible to identify the optimal search radius that minimizes conditional bias. Furthermore, it is also feasible to define variance correction factor for reduction of the smoothing effect from exploration block models. Both of these components are key to the accurate estimation of recoverable reserves. IntroductionThe accurate estimation of recoverable reserves is critical to decision making in different phases of feasibility study and mine planning. Much attention for improving the methodology of estimation has been focussed on the effect of the change-of-support (Parker, 1980; Dagdelen, 1996). For example, it is essential to make a volume- variance correction to the estimate of multiple indicator kriging (Hoerger, 1992). When the size of block, b, in the geostatistical model differs from that of selective mining unit (SMU), v, a volume-variance correction is warranted for the prediction of recoverable reserves.Most mining plans and decisions are made prior to the availability of high density blast-hole samples. In most mining operations, the true SMU grade Zv is unknown at the time of selection. Instead, the selection is based on the estimate Z v**derived from high density blast-hole samples within the deposit G. Nevertheless, the estimate Z v * of recoverable reserves in the stage of mine planning is derived from exploration data. At the end, the production result must be reconciled to the estimate Z v * . In other words, the selection is based on Z v** from blast-hole samples, while the final production figures are reconciled to Z v * from exploration drilling. For a given preselected cutoff grade z0, the actual mining panels will consist of the units having the estimated grade Z v** =z0 rather than the true grade Zv =z0. The difference between Z v** and Zv is usually of less concern."

Jan 1, 1998

By G. G. Richards, D. J. Rioux, R. L. Stephens

Teck Cominco Metals Ltd. operates an integrated zinc-lead complex at Trail, British Columbia, Canada. The year 2007 marks ten years of operation of KIVCETTM flash smelting technology for the treatment of zinc plant residues and lead concentrates. Since start-up in 1997, the furnace throughput has been increased to exceed its design rate and other metallurgical performance targets while continuing to meet its environmental objectives. This was achieved through resolution of key mechanical issues, improved understanding to stabilize the reaction shaft operation and control furnace accretions, significantly reduced boiler corrosion by molten chloride salts through the extensive application of weld overlay, a suite of projects to improve furnace integrity, and some debottlenecking of the surrounding unit operations in the lead smelter. The combination of increased feed rate and improved on-line time allowed the KIVCETTM furnace to set a new quarterly feed throughput record of 129,300 tonnes in the first quarter of 2008.

Jan 1, 2008

By I. Donohue, M. Pearson, E. Barrette

"This paper presents the technique and benefits of the finite element approach for designing the refractory lining in pressure oxidation autoclaves. One-dimensional equations are used to develop an initial refractory design. ANSYS Parametric Design Language (APDL) scripts are then used to build and analyse a more accurate three-dimensional finite element model to verify the refractory thickness, determine weld overlay requirements, and assess mechanical stability. The APDL scripts provide a cost effective means to quickly evaluate various boundary conditions and multiple designs to determine the optimal lining configuration and nozzle layout.INTRODUCTIONNew ore processing facilities demand increased capacity, requiring hydrometallurgy processes that have larger reactor vessels operating at higher pressure and temperature. Many pressure hydrometallurgy operations require vessels with an impermeable membrane and one or more courses of refractory or ceramic brick. The membrane provides corrosion protection for the vessel shell and the brick provides thermal protection for the membrane. Designing a refractory lining with an economic service life as a thermal barrier requires the refractory to be erosion resistant, chemically compatible with the process fluid, and mechanically stable. A fundamental understanding of the factors affecting the lining system is essential as designs move further away from the industry’s experience base.During basic engineering the refractory lining design is developed using one dimensional cylindrical conduction equations for heat transfer and classical hoop stress-strain relationships for determining mechanical stability. The results of the thermal calculations specify the refractory thickness that should prevent the membrane temperature from exceeding the design limit. Mechanical stability of the lining is determined by examining the sensitivity of lining stability with respect to various parameters. There are three criteria that must be satisfied to conclude mechanical lining stability:"

Jan 1, 2012

By M. J. Marinigh

Increased safety requirements, higher operational costs, greater environmental restrictions, and new competitive processing techniques are the challenges smelter operators must confront in order to remain economically viable. In converting furnaces which have tuyeres such as the Noranda Reactor and the Teniente, Peirce Smith and Hoboken converters, efficient tuyere line management is critical to optimizing blowing rates, increasing refractory life, and improving safety. This paper will describe recent improvements made to equipment used for tuyere punching, tuyere silencing, tuyere pyrometry and refractory drilling of tuyeres and how the proper application of the equipment can lead to operational and safety improvements.

Jan 1, 2007

By Tai Sik Lee

Why ISRU into Space Exploration are important NASA and International Mission statements calls for the sustainable human exploration of the Moon, Near-Earth asteroids, and Mars Common Exploration Goals and Objectives are Strongly influenced by ISRU Extend Human Presence: Continually increase the duration and level of self sufficiency at all destinations Develop Exploration Technologies and Capabilities: Develop and validate tools, technologies, and systems that extract, process, and utilize resource to enable exploration missions Perform Science to Support Human Exploration: Characterize available resources at destinations Stimulate Economic Expansion: Encourage commercial services and create new markets, including markets for discovered resources Enhance Earth Safety: Test techniques to mitigate the risk of asteroid collisions with Earth

May 1, 2013

By G. S. Hume

THE Plains of east-central Alberta herein described embrace an area from Viking east to the Saskatchewan boundary and from North Saskatchewan river south to Coronation and Monitor (Figure 1). By far the greater part of this area is deeply drift-covered, and .outcrops of bedrock are relatively few and often widely separated. Within the area there are large morainal hills and others of considerable extent that superficially have all the characters of morainal hills but contain a core of bedrock. These latter, then, were hills when the ice sheet traversed the country and only have been modified by glacial agencies. In many places on them, the drift is but a thin veneer, as is certainly the case in part of the Neutral hills (Figure 2) northeast of Coronation and north of Monitor. In other cases, however, as in the Blackfoot hills, southwest of Lloydminster, the drift is sufficiently thick to conceal practically all the bedrock and in many places no information is available as to whether a bedrock core, representing a pre-glacial hill, is present. There is no question, however, that the larger river valleys, as for example those of the North Saskatchewan and Battle rivers, are in part at least pre-glacial. Proof of this can be demonstrated in many places, because obviously the valleys must have been present in pre-glacial times to allow glacial deposits to have accumulated in them. It is also known that inter-glacial deposits occur. At one locality in Battle River valley, in sec. 30, tp. 45, range 2, west of the 4th mer., the following section occurs( l ): 15 feet of boulder clay with granite and other boulders. 56 feet of stratified sands, clays, and gravels containing pebbles of Precambrian rocks and fresh-water shells. From this it is apparent that the 56 feet of stratified sands, clays, and gravels must have derived their Precambrian pebbles from a previous glaciation of which the overlying boulder clay represents another ice advance in this area. Thus, although the river valleys contain glacial and interglacial deposits, they have not been filled by them to such an extent that the drainage has been diverted, and in many places, especially in the case of Battle river and some smaller streams, the size of the valley is altogether out of proportion to the size of the stream it now contains.

Jan 1, 1937

By A. H. Lang

THE recent production of important quantities of high-grade muscovite at the Purdy mine, near Eau Claire, Ontario, bas brought that district into prominence and bas added another strategic mineral to the list of Canadian products. The discoveries are thirteen miles west of Mattawa and about two miles north of the Trans-Canada highway and the Canadian Pacific railway. HISTORY Clear mica of low power factor is in considerable demand in Canada and in the United States for war purposes such as radio and telephone condensers, aircraft spark-plugs, radio tubes, and transformers. Some muscovite (white mica) bas been produced in North Carolina and New Hampshire, but the United States trade bas depended largely on importations of muscovite from India and of phlogopite (amber mica) from Madagascar. For many years Canada bas been a substantial producer of phlogopite, but was unable to compete extensively in the United States with importations from abroad. Canadian production of muscovite bas been negligible as no important deposits were known. Ever since the construction of the Canadian Pacific railway, attempts have been made from time to time to mine the pegmatite dykes in and near the Eau Claire area, but, although some feldspar has been mined, no appreciable muscovite was produced. Lace in 1941, J. Purdy and H. MacDonald discovered a dyke containing large crystals of high-grade muscovite from which they are reported to have sold $700 worth of mica. They recorded claims 35974 and 35975 in December, 1941, and claim 36095 in May, 1942.

Jan 1, 1943

By Balmer Neilly

We are regularly told that before making a new investment one should seek the advice of his banker. If we were to place the subject matter of this paper before bankers. other than those who have experience in our mining camps, their reply would probably be evasive. However, if for example: a mining company asks them for a loan and offers as security certain mining investments, they are, in most cases, explosively candid. The idea is preposterous, unless, under Section 88 of the Bank Act, the mining company is able to deposit with the bank, gold or silver bullion, to an amount sufficiently in excess of the loan, to provide for what the banker describes as a reasonable margin of safety in case of contingencies. In addition the directors of the mine personally must jointly and severally guarantee payment of the loan. With any of these conditions missing the banking atmosphere becomes chilly. The local manager explains that the general situation, and particularly European conditions, are so unsettled that head office has warned him that his discretionary powers must not be exceeded under any circumstances.

Jan 1, 1924

By W. Zheng

Pipelines can develop stress corrosion cracks in either intergranular or transgranular form. Since the mid-1980s, numerous colonies of transgranular cracks have been found across Canada and many other countries in the world. While the intergranular form of cracking has been well studied in the past 40 years, the mechanisms governing SCC in near-neutral pH environment, i.e., the transgranular form of the cracking, are yet to be understood in greater depth. Over the past ten years or so, a large number of research publications have been available on this subject and this paper summarize our latest progress in understanding the mechanistic aspect of the problem. Better understanding of the role of mill scale surface and the steel metallurgy in crack initiation has been indicated in the recent literature. However, the initiation of SCC in the lab research still relies on loading conditions that are far more aggressive than those encountered in the field. Most crack growth studies in the past are also performed under very aggressive mechanical conditions, which could have prevented the observation of environment effects. However, more recent research at lower K or Delta K ranges seems to suggest a strong role of the environment. Naturally, modeling of growth should reflect the effect of the environment, steel metallurgy, and the changing mechanical properties of the pipe steel with time. For a specific steel in a given environment, the crack growth rates tended to increase with the strain rate, indicated either by the nominal applied loading frequency or by the calculated crack tip opening rate. Future research needs to address the issue of concurrent growth of multiple interacting cracks. More attention should also be given to concurrent initiation of multiple cracks in a colony, as failure is usually caused by a coalesced crack not by an individual crack. The effect of soil environment should not be limited to the chemistry of soil solution; other factors such as cathodic processes, the variation of environment with time and physical conditions of coatings should also be considered as part of the study.

Jan 1, 2005

By O. Babak, J. G. Manchuk

ABSTRACT A significant factor in evaluating bitumen recovery from an oil sands mine is the particle size distribution (PSD). Increased understanding of mined ore quality and improvement in predictions of recovery can be achieved through PSD modeling. This paper addresses PSD modeling using geostatistics. PSDs may be described using many discrete particle sizes, making this a challenge. The approach parameterizes PSDs with a few statistics. A lookup table is used to reconstruct the PSDs based on models of the statistics. The workflow is applied to Total E&P Canada’s Joslyn Lease and yields good results that reproduce input statistics without introducing artifacts.

Jan 1, 2013

By Kaiwen Xia, Bibhu Mohanty, Per Svedensten, Sheng Huang

"The mechanics of crushing and grinding operations in mining and excavation processes has been investigated in a laboratory simulation study. It employs a multi-particle bedded rock target, which is subjected to multiple impacts. The impact set-up consists of a Hopkinson pressure bar and a Piston-holder system. The apparatus, employing a 38 mm diameter pressure bar, was used to apply varying but calibrated dynamic loading force on the rock particles. The energy consumed by the sample during fragmentation was determined by considering the energy carried by the incident wave and the reflected wave. The Pistonholder system is used to hold rock samples and to recycle fragments after each test for particle size analysis, for single as well as multiple impacts. The feed size selected was in the range of 9.5 to 12.7 mm for all rock samples, and the impact velocity was set at 14 m/s. Two strong granitic rocks and a relatively weak limestone were the target rocks. The resulting particle size distribution after each set of impacts, ranging from single to 10 consecutive impacts, were analyzed, and various size distribution functions (i.e. Rosin- Rammler, Swebrec, Grady and Gilvarry functions) were fitted to compare their suitability in predicting the fragment size distribution for each rock type. INTRODUCTIONCrushers are widely used in the mining industry all over the world. Understanding fragmentation behaviour of rock under crushing process is fundamental to improved productivity and efficiency in mining operations. This is particularly so as all subsequent size reduction processes such as crushing and grinding are far more energy intensive than the initial blasting process employed in breaking of in situ rock. A considerable body of experimental studies exists on the behaviour of rock crushers for specific rock types in order to aid in the design of various types of crushers. However, these studies are mainly site specific, that is, the results are largely empirical, and the fundamentals of fracture process that lead to size reduction have not been dealt with adequately. Most such studies have attempted to link the input parameters, such as feed size and crusher parameters, with output particle size, and global energy expended in the process. However the physical mechanism of crushing process is still not well understood. First of all, the energy consumed by the rock sample is hard to calculate during standard crushing or grinding tests; secondly, multi-particle test is hard to perform in the laboratory due to irregular shape of the subject rock sample. In This paper, describes a laboratory crushing apparatus for multi-particle rock samples, with sufficient control of the energy expended in the process, with a view to relate creation of new fracture surfaces in the size reduction process."

Jan 1, 2015

By W. A. Lang

"IntroductionCARBONIZATION, gasification, and chemical utilization of coal are interrelated topics, which makes it difficult to review one without indicating its connection with the others. Hence, in Progress in Coal Technology, Series No. 5: Carbonization, reference was made to gaseous products recovered in the carbonization of coal, and .to a number of chemicals made from the tars, light oils, and ammoniacal liquors which are by-products of coal carbonization.In this, the sixth paper in the review series, prime consideration will be given to the complete gasification of coal to give a fuel for domestic industrial, or power purposes and a synthesis gas suitable for the manufacture of gasoline, Diesel oil, and chemicals. The hydrogenation of coal, an alternative source of liquid fuels and of chemicals, will be reviewed, as will be a number of processes for •the recovery of chemical products from coal by extraction and chemical treatment."

Jan 1, 1952

By J. Bednar, R. R. Rogers, W. Dingley

"Zinc is by far the most important metal used for protecting steel from the ravages of corrosion, and cadmium is also used extensively for this purpose. These metals are applied by electrodeposition in cyanide baths when a particularly good appearance and high throwing power are required. One great disadvantage in using these baths has been the decrease in cyanide concentration and the increase in carbonate concentration that takes place during the plating. Another disadvantage has been the development of serious embrittlement in high-strength steels. The present authors have developed new cyanide baths for electroplating both zinc and cadmium on steel. These baths are stable in composition during plating, they have not produced appreciable embrittlement in the high-strength steels that have been investigated up to the present time, and they permit the use of considerably higher plating current densities. In addition, they produce extremely fine grained coatings that are attractive and have excellent adherence and covering properties. Brighteners can be used in the plating baths if bright finishes are required."

Jan 1, 1967

By P. Leo

Al-Mg-Si alloys are widely used as medium-strength structural materials; extrusion is the most common processing route. In the present hot deformation investigation of a 6060 alloy, the microstructure of the alloy has been analyzed in the as-cast state, after homogenization heat treatment and after hot deformation by tensile tests in the range 400-490°C and 10-4 to 10-2s-1 on both as cast and homogenized alloys. After deformation the microstructure of the as-cast alloy exhibited cavitation. The flow curves at the lowest test temperature T show a gradual softening after a stress peak, being more evident for the alloy deformed in the homogenized state in association with a high yield stress; at higher T a plateau is attained which is lower as T rises and strain rates decrease. For each fixed T, the ductility decreases as strain rate increases for the homogenized alloy whereas, for the as cast alloy, it rises with strain rate. Constitutive analysis gives Q = 240kJ1mol for the homogenized alloy in agreement with published values; this indicates a more rapid strength decline with rising T than Al, suitable for good hot workability along with the lack of cavitation.

Jan 1, 2011

By J. R. Gill

Introduction The property and plant of the Falconbridge Nickel Mines, Limited, is situated about 13 miles northeast from Sudbury, in Falconbridge township, near the eastern extremity of the southern Nickel Range. As early as 1899 or 1900 some work was clone on this property by the late Thos. A. Edison, when a shaft was sunk through 80 feet of overburden to within a few feet of the ore-body. At this point quicksand was encountered, which made it impossible to continue with the equipment at hand. As a result, the activities of the Edison party ceased in this section. There was no further progress until 1915 and 1916, when an extensive diamond-drilling campaign, carried out by the E. J. Longyear Company, located the ore-body that is now being worked. The property was acquired by the present operators in 1928, and in September of that year active mining development was commenced. Features Influencing Design Of Plant Early in 1929 plans were prepared for a smelter and the necessary crushing and sorting plant. In spite of the general trend towards the reverberatory furnace as a smelting unit, it was decided to erect a blast-furnace plant. The limited tonnage to be treated, of course, influenced this decision to a great extent. However, it was known that, with the proper procedure, extremely favourable results, both economic and metallurgical, could be obtained in blast furnace smelting. The possibility of very low slag losses, the simplicity of operation by the elimination of roasting plant, fuel plant, etc., the ability to handle coarse feed, and the lower initial cost, were considered factors in favour of the blast furnace. Notwithstanding the fact that we might be called on to treat a certain amount of concentrate, it appeared that the blast furnace was the proper unit for the contemplated operation.

Jan 1, 1932

Over five decades ago Kitchener et al. in England and La Mer and Healy in the US were advancing our understanding and application of flocculants, primarily related to water treatment and filtration of sludge. This paper identifies the beneficial uses of flocculants in the mining industry and revisits some less common applications. Flocculants are used in unique ways in the mining industry: (a) to increase the effectiveness of sediment ponds to achieve discharge compliance; (b) to eliminate air emissions and costs associated with concentrate drying; (c) to reduce soil loss by applying a flocculant to erodible soils, and reducing wind and water erosion; (d) to remove/thicken metal precipitates in acid rock drainage treatment; and (e) to enhance clarification and thickening in mineral processing. The mechanism of how flocculants, coagulations and potentially-determining ions function is described and how their use can be controlled and optimized. The potential toxic effects of flocculants and coagulants when used to achieve effluent permit discharge compliance for suspended solids is discussed. A review of numerous best management practice (BMP) guidelines for the design and operation of sediment ponds treating mine site runoff to remove total suspended solids (TSS) and turbidity revealed an absence of a predictive methodology to address regulatory discharge compliance for TSS concentration, turbidity and flocculant-induced toxicity. An essential component of pond design is the need to determine whether flocculants and/or other settling aids are required based on the site-specific soil particle size distributions upslope of the pond. Procedures are provided to predict the need for settling aids and estimate pond discharge quality and downstream impact for TSS, turbidity, toxicity and sub-lethal toxicity. The need to develop BMP guidelines are discussed for (a) the application of flocculant to surface soils to reduce erosion, (b) the application of flocblocks to increase the ?sediment control? aspects of erosion and sediment control, as part of the mine site erosion control plan strategy and (c) the application of flocculant to silt socks to treat mine site runoff.

Aug 1, 2013

By A. Anderko, V. G. Papangelakis, G. Moldoveanu, G. Azimi, M. Carlos

"OLI Analyzer is a software package that uses the powerful Mixed Solvent Electrolyte (MSE) model to simulate the behavior of multicomponent electrolyte solutions from infinite dilution to the limit of fused salt, and from temperatures below the freezing point up to near critical temperature of the mixture. The software also allows the creation of thermodynamic parameters for new chemical systems unavailable yet in public-domain or commercial software databanks. This communication reviews the basics of the model and provides some examples of modeling hydrometallurgical applications with emphasis on high temperature applications, including calcium sulfate scale formation in autoclaves, high temperature pH inference and iron control. INTRODUCTIONModeling of electrolyte systems has been of particular interest to various industrial processes, such as separation processes (e.g., solution crystallization, extractive distillation, seawater desalination or bio-separations), environmental applications (e.g., gas treatment, wastewater treatment or chemical waste disposal) and hydrometallurgy (e.g., pH control and neutralization, iron control, scaling and fouling of equipment). Using a chemical model, time-effective predictions of various properties of electrolytes can be obtained, which is beneficial not only during process monitoring, but also during process optimization and process scale up. As a result, pilot scale studies can sometimes be eliminated where budgetary constraints exist. Development of such a powerful model requires the use of a speciation-based model, in which solution chemistry is explicitly addressed (as compared with some models that treat electrolytes either as undissociated or fully dissociated systems), despite being computationally challenging. In addition, as a feature of electrolyte systems, speciation equilibria inherently influence the phase equilibria due to complex formation, ion pairing, and acid-base reactions. Therefore, how the electrolyte solutions behave at various conditions may differ significantly due to the non-ideality, which must be carefully addressed to obtain a model that is applicable to a wide range of conditions such as concentration, temperature, pressure and solvent system."

Jan 1, 2012

By A Frydrychewicz, J. Mirza, J. Lipkowski

The objective of this work was to understand the mechanisms of action of additives, such as thiourea, that enhance gold leaching in thiosulfate solution. The leaching reaction and surface passivation were investigated using linear sweep voltammetry. Leaching currents were determined using analysis of current-potential curves and the mixed potential theory. The gold-electrolyte interface was further characterized with surface enhanced Raman spectroscopy. The results show how thiourea prevents formation of oxysulfur compounds, which passivate the gold surface. Other molecules such as 3- m ercaptopropionic acid and L-cysteine were also studied as possible additives to prevent passive layer formation.

Jan 1, 2011

By D. Runnels, Daniel Roy, Ricardo Esteban, J. Torrealba-Vargas

"An intuitive way to reduce power consumption in grinding operations is to feed the grinding circuit with finer feed by enhancing blasting and fragmentation control. The optimization of blasting with the objective of minimizing power consumption in grinding is not new.The study was based on a Canadian mine that processes a very hard ore. BBA conducted blasting/fragmentation and grinding circuit surveys in 2014. The results of the exercise were used to develop a base case model to simulate the effect of blasting in the operation on the grinding circuit. Tools for fragmentation simulations, particle size measurement and crushing/grinding simulations were used with the objective of reducing the OPEX costs including power consumption.The paper describes the steps involved in the model optimization as well as an economical evaluation of the OPEX savings.INTRODUCTIONIn 2014 BBA was retained by one of its clients to conduct a crushing and grinding survey. The objective of the survey was to update the grinding circuit model with production data and also to develop a tool to investigate opportunities for process improvement.A second phase of the study involved the development of drilling and blasting and crushing models. The models were used to diagnose the operations and to investigate opportunities for process improvement.The objective of the present study is to describe the approach and to identify potential improvements to overall mine site operating costs by better integrating mining and milling operating costs with blasting and grinding models."

Jan 1, 2016