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By D. B. Dreisinger, M. Rasouli

"Developing technology to address the environmental hazards associated with selenium in mine-impacted waters has been a serious challenge. Ion exchange (IX) has been identified as a potential treatment technology. This paper begins with a review on selenium adsorption with commercially-available basic anionic exchangers (BAS). It then looks at the use of resins for selenium removal via modification with the addition of -O, -N, or -S-containing chelating ligands and chelating polymeric ion exchangers pre-loaded with immobilized metal cations. The synthesis of chelating exchangers requires a final product with a highly stable metal in the ligand-metal complex. The nature, oxidation state, size, and affinity of the metal for the target oxyanions and the size, degree of protonation and space configuration of the oxyanion are among critical factors affecting the oxyanion uptake. There is a limited number of studies on the critical parameters affecting the selenium affinity for chelating exchangers. Such a study could fill in the gaps of our understanding of selenium-metal-chelating ligand interactions and assist in developing a new ion exchanger. In addition to commercial IX resins, layered double hydroxide materials (LDH) have received attention for oxyanion removal from waste water. The adsorption capacity of the LDHs are affected by the crystallinity of LDH, the nature of metal components, the ratio of metals, charge and type of anion, and the space between the layers. In particular, the Friedel phase (FP), a member of the LDH family, showed high adsorption capacity for selenate removal from synthetic solution. A study is currently underway at the University of British Columbia to investigate the effect of different synthesis methods and aging on the suitability of FP for selenium removal from mine waste water."

Jan 1, 2017

By A. Galibois, H. Monette, J. L. Collins

This paper deals with the problem of caving, which occurs in varying degrees in blast holes before loading. It is shown that the distribution of the amount of caving in materials may be described by a gamma density function. A decision model to determine the optimal depth of over-drilling 'in order to minimize the expected additional cost per hole is described. Two different policies are discussed. In addition, charts which permit the mine operator to realize significant savings have been drawn for different actual situations.

Jan 1, 1971

By B. R. Rakishev

Balanced development of mining works at all the benches of a working zone by use of the excavator-automobile complex is achieved by transition to the technology of the bench excavating with cross panels by the two-sub-bench scheme with the changing levels of the working platforms (is patented in Kazakhstan). In deep quarries realization of this technology will allow to reduce the current volumes of the stripping ore excavation by 10?15 % and more, to increase the opened reserves of minerals by 20?50 % to decrease volume of mining-capital works for construction of stripping excavations by 2?4 times and to provide efficient use of powerful excavator-automobile complexes.

Aug 1, 2013

By Cindy Schiewek

Industrial injury occurrences are an ongoing concern for Mine Operators. Along with the personal suffering of injured workers comes an increase in compensation and productivity costs. Growing recognition of repetitive stress and bodily injuries, accompanied by recent studies, validates the assumption that a relationship exists between ergonomic injuries and machine design. Intuitively, there is a belief that an ergonomically designed machine will reduce repetitive stress injuries through design and education however; quantifying this belief has been a challenge for Mine Operators. Sandvik Tamrock has undertaken a project aimed at developing a business model to assist in quantifying the benefits of ergonomic intervention. This model focuses on distinguishing and quantifying this method of intervention to allow for a better evaluation of the machine. For simplicity, the project initially focused on the Face Drill Jumbos. The target of the project was three fold: !" Recognition of the cost drivers for compensation; ergonomic injuries !" Identification of the relationship between ergonomic machine design, and the decrease of the negative effects associated with the cost drivers !" Systematic prioritization for ?prevention by design? The project findings substantiate the expected reduction in injuries and compensation claims. Based on all ergonomic intervention studies conducted, each case showed a reduction in compensation cost; through prevention by design, one can reduce the amount of potential risk. The paper addresses the resources and methodology used, along with the findings and its relevance to the issues that face the Mining industry.

May 1, 2003

By P. E. Fox, R. S. Cameron

"The QR gold deposit lies in the Cariboo plateau region of central British Columbia. The deposit was discovered in 1977 and since then a mineable reserve of 1.3 million tonnes grading 4.7 g/t Au has' been outlined in three separate zones. Soil sampling of glacial tills followed by diamond drilling of favourable host rocks proved to be key exploration techniques.The deposit is situated in the southern Quesnel terrane along the eastern fringe of the Intermontane Belt which here comprises a sequence of basic and intermediate volcanics and a series of stocks of alkaline affinity; generally diorite, monzonite and syenite. Hornfels and epidote-rich ferromagnesian exoskarn and sulphide-rich mantos have developed in a metamorphic aureole formed around a central diorite stock. Gold-rich zones lie along the outer periphery of the aureole where bodies of gold-bearing epidote-rich skarn and auriferous mantos rich in epidote and pyrite have formed in beds of calcareous tuffite lying at the top of a thick basaltic sequence. The deposit is regarded as' a subclass of gold skarn deposits. Diagnostic features are its association with alkalic intrusive rocks in a subvolcanic setting and the presence of oxidized, epidote-rich mineral assemblages.IntroductionThe QR gold deposit lies within the Cariboo plateau region of central British Columbia, 58 km southeast of Quesnel. The deposit, owned by Kinross Gold, was discovered during a regional reconnaissance program by Dome Exploration (Canada) Limited and Newconex Canadian Exploration in 1977. Considerable exploration and development has been done since that time. Mineable reserves of 1.3 million tonnes grading 4.7 g/t Au have been outlined to date in three zones."

Jan 1, 1995

By K. E. Waters, N. Brodusch, R. Gauvin, A. Jordens, Teng. C., H. Demers

Rare earth elements (REEs) become increasingly significant for renewable energy devices and high-technology electronic products because of their large-scale popularity and applications. In this project, a field-emission scanning electron microscope was used to characterize the composition and distribution of REEs-bearing minerals. X-ray elemental maps were acquired with a large area x-ray detector (60 and 80 mm2 collecting area) and annular detector (60 mm2 collecting area), which allow fast x-ray acquisition at high count rate. These elemental maps were transformed into phase maps, which are used to identify the composition of the mineral phases and the REEs distribution over a large area. The phase maps are an easy way to distinguish the phases with and without REEs and compare the efficiency of different REEs extraction processes. Different methods (manual and automatic) for producing phase map were studied by comparing the distribution of REEs obtained from the same area.

Jan 1, 2015

By J. Budac, J. Dennett, D. Mayne, P. Nawrocki

"The Nickel/Cobalt operation in Fort Saskatchewan, Alberta has successfully used an oxidative ammonia leach process to refine a variety of feeds into high quality nickel and cobalt products for over 60 years. Fundamental changes to the refining process were made when the major feed was converted from nickel concentrate to cobalt rich mixed sulphides in the early 1990s. Since the early 1990s, the production capacity of the refinery has expanded to match increases in both mixed sulphides and other feeds. In addition to increasing the production capacity of the refinery, other changes have been required in order to improve the operability and reliability of the refinery as well as to deal with increasingly stringent safety and environmental requirements. This paper describes recent changes at the refinery including changes to the flow sheet, improvements in unit operations, incorporation of new feeds, management of byproducts, and control of impurities.INTRODUCTION The Cobalt Refinery Company (Corefco) plant in Fort Saskatchewan processes nickel-cobalt mixed sulphide intermediate produced at the lateritic nickel mine and high-pressure acid leach (HPAL) facility in Moa Bay, Cuba. Both operations are jointly owned and operated by Sherritt International and General Niquel of Cuba. The mixed sulphide, along with other feed materials, is processed at the Fort Saskatchewan refinery using a pressure ammonia leach-hydrogen reduction process to produce nickel and cobalt metal. This refinery was originally constructed in 1954 to treat nickel concentrate from Sherritt’s Lynn Lake mine in Manitoba. (Benson and Colvin, 1964; Boldt and Queneau, 1967; Forward, 1953; Forward and Mackiw, 1955; Kerfoot, 1989) From the mid-1970s until the early-1990s, the facility operated as an independent refinery, treating nickel-bearing feeds from around the world. The flowsheet was changed in 1992 to address the increased cobalt content of the feed. (Cordingley and Krentz, 2005; Kerfoot and Cordingley, 1997) The flowsheet was adapted further in 2009 to improve cobalt speciation in the leach process, which allows better cobalt-nickel separation. The 2009 iteration is shown in Figure 1. Three ammonia leach stages were used to ensure high recoveries of nickel and cobalt. Underflow solids from the final leach stage contained mainly iron oxides. One of the features of the leach process is the innovative recycling of ammonia. Ammonia vented from the leach process in tail gas and from atmospheric tanks is recovered and recycled into the refinery using water based scrubbers and a high pressure distillation process. Indeed, roughly 250 t NH3/d is recovered as distillate and recycled back into the process. Also, air enriched with ammonia which is vented from the later first stage autoclaves is recycled to the lead first stage autoclaves to maximize oxygen and ammonia utilization."

Jan 1, 2017

By C. S. R. Rondestvedt

In February 2010, Teck?s newest Concentrator at Mina Carmen de Andacollo (CDA), Andacollo, Chile was commissioned. The Concentrator is a single line configuration, comprising of one 36 ft diameter x 20 ft long SAG mill driven by an 18,000 hp gearless drive. The SAG mill feeds two ball mills each 25 ft in diameter x 40.5 ft long, each driven by a total of 19,000 hp through dual pinion drives. A series of four phases will be reviewed from operational readiness, mechanical completion, commissioning, and ramp-up. Also, now after 6 months of operation, this paper will review the significant steps taken during ramp-up enabling the announcement of commercial production, in October 2010.

Jan 1, 2012

By F. Daniel Rosenkranz, Peter L. Silveston

Experiments investigating the treatment of a ground wood white water waste from an Ontario pulp and paper mill by an HVCB coal are reported. Adsorption capacity for the waste, with a soluble COD contribution of 2,100 mg/I, amounted to 0.17 per cent, by weight, of the Nova Scotia coal used. Percolation of the white water waste through a coal bed indicated that soluble COD is removed. For finely ground coals, over 90 per cent of the suspended solids in the waste are retained on the coal. Plugging of the coal bed is rapid, so that any treating process using filtration would have to renew the surface of the bed frequently.

Jan 1, 1970

By T. Binnert Haites

INTRODUCTION NUMEROUS examples of troubled zones, interfering with the normal development of coal seams, have been cited in the literature. From a geological point of view they can be subdivided into structural and sedimentary troubles. Of the latter type, wash-outs are usually the most bothersome. Some years ago, A. A. Thiadens and the author arrived at the conclusion that they represent fossil river-beds. A method of predicting the course of these rivers was developed, which has been successfully applied in the Netherlands coal measures, and more recently by P. Stassen in some of the Belgian coalfields and by the author in the Sydney coalfield. The Sydney coalfield has long .drawn the attention of geologists, and three main periods of systematic geological research may be distinguished. The first period, 1872-1900, is covered by the studies of Ch. Robb and H. Fletcher (32, 10-13) (1). Their detailed sections of the cliffs have lost nothing in value, and are frequently consulted today.

Jan 1, 1951

By Samuel Frimpong

Green house gases have become a major concern within the international community over the last two decades due to their potential link to global warming. Carbon dioxide (CO2) is the principal greenhouse gas. In the Kyoto Agreement, Canada has committed to reduce emissions by 6 % below 1990 levels by 2012. This presents a serious economic challenge to Canada and Alberta. Over the next decade, oil sands production expansion, population and industry growth and energy demand will increase CO2 emissions. Current and future CO2 emissions and their economic implications in Alberta will be critical in formulating a comprehensive and balanced policy for dealing with concerns in this area. Disposal of carbon dioxide (CO2) in land aquifers is a potentially viable option for Alberta in dealing with long-term CO2 emissions. Studies have confirmed the existence of appropriate aquifers in the Alberta Basin for CO2 storage over a long geological period. Carbon dioxide is an ideal candidate for aquifer disposal because of its high density and solubility in water at relatively high pressures. In this study, the authors develop a computer simulation model of a scaled aquifer disposal system. The scaled model consists of an injector well, aquifer environment with dominant Ca++ and Mg++ cations. Liquefied CO2 is injected at an appropriate pressure and concentration through an injector well model. The injected CO2 migrates from the point of contact between the injector well and the aquifer domain to the main regime of the latter. The rate of migration is a function of porosity, permeability, cations, aquifer fluid flow regime and CO2 injected pressure. These models are validated using flue gas data from the 546 MW Wabamum Power Plant in Alberta. The total energy requirements for aquifer CO2 disposal system are distributed between a minimum of 105 MW and a maximum of 172 MW, with a mean of 132 MW and a coefficient of variation of 10%. The results show that there is significant variability in all the energy requirements for the CO2 disposal system. The total energy requirements for the disposal system as a fraction of the total power generated by the Wabamum plant of 546 MW could be between 0.19 and 0.32. This is a very significant energy requirement and thorough analysis must be carried out to reduce this variability and energy requirements.

May 1, 2001

By A. R. Barnes, N. Stubina

Increasingly, gold producers are forced to treat ever more refractory ores. While ores containing pyrite, arsenopyrite and carbonaceous material have been subjected to complete pressure oxidation (PDX) as the standard process for such ores, recent improvements in fluid bed roasting technologies have led to a resurgence of interest in roasting as a viable alternative. The lower capital and operating costs of roaster installations add further impetus to this trend. The Extractive Metallurgy Group at Xstrata Process Support operates four fluid bed reactors of various sizes which have been utilised on a large number of projects to treat highly refractory ores. Preliminary mineralogical modelling of both the physical and chemical aspects of the roasting process and subsequent testing under carefully controlled conditions has allowed clients to obtain gold recoveries approaching or matching those achievable by PDX. The flexibility of the units to operate in various modes- " bubbling bed", circulating bed, two stage, sub-stoichiometric and combinations of these, and the range of sample sizes accommodated, from a few kilograms to a few tons, has enabled XPS to accommodate clients with a wide variety of gold bearing refractory ores from all over the world. This paper outlines the key challenges of fluid bed roasting of refractory gold ores, describes the methodology used to design the testwork program and provides some results from select test campaigns.

Jan 1, 2011

By Lauri Gregg

Key Message Energy focused Change Management Process that engages operations managers is the missing tool needed to build capacity for energy/GHG management

May 1, 2007

By John Convey

This short paper deals with the subject of research and its relation to productivity. All who have stopped to even think about industrial re-search and its impact on the nation-al economy take for granted that research and development are pre-requisite to increased productivity. It is another matter, however, to identify and properly evaluate the many factors entering into the relationship between the two. Some studies are currently underway in the United States on the subject, but, so far, nothing much in the way of conclusive data has come to light. In Canada, we have not yet even produced any statistical figures on national productivity, although work is now being done on this subject and information will soon be available. The usefulness of being able to measure the benefits of investment in re-search and development in terms of industrial growth or productivity need not be laboured for the benefit of those interested in research management.

Jan 1, 1964

By K. Kawagishi, K. Matsumoto, Y Koizumi, H. Harada

A new burner rig for cyclic and hot corrosion testing of Ni-base superalloys and high-temperature coatings has been developed at the National Institute for Materials Science (NIMS) in Japan. The concepts of the rig design include: use of kerosene as fuel, easy operation for materials research and multi-specimen testing capability per test run. The burner rig consists of six blocks including combustion block, corrosion-solution injection block, furnace block, specimen block, controller block and outdoor facility block. During verification testing, it was confirmed that the rig had accurate specimen temperature control within ±1? from 600 to 1100? and automated easy operation. Cyclic testing of several Ni-base superalloys was conducted. The results from 50 cycle testing indicated that a new NIMS alloy developed for 1700? class gas turbine had higher oxidation resistance than CMSX-4. This new burner rig testing capability at NIMS can be very useful for future oxidation, hot corrosion and coating durability studies.

Jan 1, 2010

By C. R. Fast, G. C. Howard

The loss of fluid to the formation adjacent a fracture governs the areal extent of the fracture and the success of hydraulic fracturing as a production stimulation technique. The three flow mechanisms which control this loss are the result of the viscosity of the fracturing fluid and the permeability of the formation to the fracturing fluid, its wall building properties, and the combined effects of viscosity and compressibility of the reservoir fluid. The effects of these flow mechanisms can be evaluated in terms of a fracturing fluid coefficient, the fundamental concepts of which are developed in the paper. The fracturing fluid coefficient, which may be used in calculating the areal extent of fracturing, affords a direct measure of the effectiveness of fracturing fluids. The area of hydraulically created fractures is in-creased as the coefficient is de-creased. The fifteen-fold variation noted in this coefficient for the commercially available fracturing fluids tested resulted in a six-fold difference m the calculated areal extent of the fracture system.

Jan 1, 1961

By E O. Foster

When roasting started at Giant Yellowknife Mines in 1949, it became apparent that, to prevent air and water pollution in the surrounding district, it would be necessary to collect the arsenic that was contained in the exit gases of the roaster. The arsenic collection problem was finally solved by the installation of both electrostatic and baghouse collectors. It was realized that a considerable quantity of gold-bearing dust was leaving the roaster with the exit gases. When the collection problem was solved, it was possible to measure this loss. The loss proved to be considerable and it became evident that a substantial quantity of gold could be recovered. Research programs on dust treatment began in 1958, and by May, 1960, the treatment process which is currently being followed was started in the plant. At present, the two electrostatic preci11itators, Operated at temperatures above 600°F, collect the gold-bearing dust.

Jan 1, 1963

By J. Coffin, M. Muinonen, D. Fragomeni, R. Multani, C. Deredin

"Rejection of pyrrhotite from pentlandite is of critical importance to the economics of nickel concentrate production and the main goal of the Strathcona milling operations. A joint team of XPS, Glencore Technology and Strathcona Mill personnel executed a comprehensive program of work to develop and implement strategies for increased Po rejection with focus on challenging ores containing high feed Po/Pn ratios (> 7) and significant hexagonal Po content (> 40% of total Po). This paper describes the team results including minerology, bench-scale flotation tests, and plant validation tests and modeling that have defined the path forward to improving the metallurgical performance and economics of the mill operation. Techniques to quantify hexagonal and monoclinic pyrrhotites were developed at XPS to assess the differences in their metallurgical behavior since their flotation responses are quite different. Mineralogical tools including QEMScan were extensively used to determine mineral liberation, associations, optimum grind size, and nickel deportment into pentlandite, pyrrhotite and non-sulphide gangue. Several reagents/strategies were evaluated during bench-scale flotation testing to significantly increase Po rejection. A significant shift in the Po-Pn selectivity and grade recovery curves was achieved using several strategies including the use of DETA and sodium metabisulfite, and regrind of the rougher concentrate and rougher cleaner/rougher tails.INTRODUCTION The Strathcona Mill is owned and operated by Glencore Nickel – Sudbury Integrated Nickel Operations and has been processing Ni-Cu ores from the Sudbury Basin since 1968 (valuable sulphides: pentlandite (Pn) – (Ni,Fe)9S8 and chalcopyrite (Cp) – CuFeS2). Currently Strathcona Mill receives ore mined from two main sources in the Sudbury area and produces two concentrate streams – a nickel-copper concentrate that is shipped to the Sudbury Smelter and a copper concentrate that is sent to the Fonderie Horne (Glencore Copper, Rouyn-Noranda). The general flowsheet currently used at Strathcona is displayed in Figure 1. It is highlighted by separate feed circuits for regular grade Ni ores and high grade copper ores. The copper circuit has a preflotation stage prior to a rougher-scavenger stage, a copper-nickel separation circuit, and a pyrrhotite (Po) rejection circuit."

Jan 1, 2018

By L. Kilburn

A survey of 281 mineral exploration agreements examines the ratios among three ways that may be used to purchase an interest in a mineral property, viz: pay cash, pay shams and make future expenditures on the property. The dollar value of the future expenditures exceeds that of cash or shams by about nine times in most of the 110 agreements that contain cash-expenditure or share-expenditure components. Results suggest that cash and shams are treated about the same in terms of value. Buyers and sellers haw opposing priorities for the way that they prefer to purchase a mineral property. These opposing priorities should give rise to a perceived 50:50 balance between cash/share payment and future expenditures to satisfy the idealized situation described by most definitions of fair market value (FMV). This balance between cash/share payments and future expenditures appears to be rationalized in negotiations to a FMV when expenditures are nine times greater than cash and/or payments. On this basis, it is proposed that the FMV of a property may be determined by aggregating the dollar amount of the cash/share payments plus one-ninth the dollar value of future expenditures, as set forth in the respective purchase agreement, and proportionately applying such aggregate to full property value.

Nov 1, 2005

By L. Kilburn

"A survey of 281 mineral exploration agreements examines the ratios among three ways that may be used to purchase an interest in a mineral property, viz: pay cash, pay shares and make future expenditures on the property.The dollar value of the future expenditures exceeds that of cash or shares by about nine times in most of the 110 agreements that contain cash-expenditure or share-expenditure components. Results suggest that cash and shares are treated about the same in terms of value.Buyers and sellers have opposing priorities for the way that they prefer to purchase a mineral property. These opposing priorities should give rise to a perceived 50:50 balance between cash/share payment and future expenditures to satisfy the idealized situation described by most definitions of fair market value (FMV). This balance between cash/share payments and future expenditures appears to be rationalized in negotiations to a FMV when expenditures are nine times greater than cash and/or payments.On this basis, it is proposed that the FMV of a property may be determined by aggregating the dollar amount of the cash/share payments plus one-ninth the dollar value of future expenditures, as set forth in the respective purchase agreement, and proportionately applying such aggregate to full property value."

Jan 1, 2005