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By Charles B. Newmarch

Abstract In the course of coal studies undertaken by the B.C. Department of Mines in southeastern British Columbia, special attention was directed to problems of coal seam correlation. Methods that had been used successfully in other coalfields were found, in the Crowsnest area, to have a restricted use or furnished only additional evidence that might prove helpful when used in conjunction with other criteria. A correlation technique involving semi-quantitative spectrographic analyses of coal ashes was developed. Elements detected in the ash include Si, B, P, Fe, Mg, Mn, Pb, Ti, Cr, Ga, Ca, Al, Ge, Ba, Mo, V, Ag, ?y;b, Na, Zn, Zr, Ni, Sr, Cu, K. Of these, the elements found to be most useful in correlation were Na, Ba, Si, V, and Mg. The element Na was invariably detected in the ash from one of the seams but was not found in samples taken from any of the others. In all of the four seams sampled statistically, significant differences in the amount of certain trace elements were noted. When the values obtained for these trace elements were portrayed in the form of histograms, the resulting diagrams had a characteristic shape for each seam. The diagrams provided a basis for seam identification within the limited area (8,000 feet by 4,000 feet) that was investigated. Introduction During the field seasons of 1946, 1947, and 1948 the British Columbia Department of Mines undertook a geological investigation of the coal measures of southeastern B.C. As field work progressed in the Crowsnest area it was found that, within the Kootenay formation, which contains all the commercial seams of the region, the coal beds are the most persistent stratigraphic units. Because of relatively rapid changes in ?both the thickness of the seams and the interval between seams, difficulty has invariably been experienced in attempts at correlation. Even short-range correlati0ns by able geologists who have worked in the Crowsnest coal basin have been questioned by the operating companies. It was apparent, therefore, that a more dependable correlation technique was needed so that stratigraphic and structural studies could be of greatest value. This paper presents, firstly, a summary of the results obtained in attempted correlations using methods that have been found effective in other coalfields. Secondly, a method based on semi-quantitative spectrographic analysis of coal ash is described and the apparently promising results are discussed.

Jan 1, 1950

By M. A. Vos

"Aggregates are the low-cost mineral raw material of building construction. Large volumes of aggregate are consumed each year. The availability of aggregates in southern Ontario is discussed in the context of the geological formations in which they occur. Sand and gravel are abundant in glacial deposits and in recent sediments. A knowledge of the glacial history is important for their discovery. Bedrock formations provide a variety of aggregates in Ontario. Knowledge of the rock types involved and of the depth of overburden are important for evaluation of the aggregate potential of bedrock resources in an area. Utilization of available resources intensifies as the population increases. Urban development makes it progressively more difficult to satisfy the demands of the construction industry. The effects of urban development on the aggregate resource base of an area are illustrated by developments and consumption statistics in the Toronto- centred region. There is an obvious need for a comprehensive survey of available resources in urban areas to serve as a guide in land-use planning. To fill this need, staff members of the Industrial Minerals Section, Geological Branch, Ontario Department of Mines and Northern Affairs, are engaged in mapping projects and mineral resource studies in southern Ontario as well as in some urban areas of northern Ontario."

Jan 1, 1972

By A. Supomo, H. Resendiz, C. Burbidge

"Freeport-McMoRan Inc. (FMI) commissioned the expansion of the Morenci Metcalf concentrator in 2014. The concentrator included many design and equipment innovations, including the first-of-its-kind Metso Hydraulic Roll Crusher (HRC), variable speed ball mills and variable speed crushers. In addition to the innovative design, FMI commissioned the Metso APC team to design a realistic process simulator and the plant APC. The process simulator was utilized to train operators before commissioning, which led to a smoother plant start up. The plant APC utilized the concept of dynamic constraint control, which controls the feed to the primary ball mills by “pulling” the tons from crushed rock storage bins, which then automatically are filled by the upstream HRC and secondary crushing circuits. The primary ball-mill control also adjusts the water addition to the cyclone clusters to avoid overload and achieve sufficient grind size. The constraints include in-circuit constraints for feeder capacity, screen-deck capacity, ball mill power, cyclone mass flow, pump capacity and pump motor capacity. The APC system was implemented shortly after the start of commissioning and immediately demonstrated increased throughput and an ability to highlight and quantify process constraints and bottlenecks. The following paper outlines the control strategy, discusses system implementation, results and challenges.INTRODUCTION The FMI Metcalf Concentrator is located in Morenci Arizona on the site of the old original Concentrator. The new Metcalf concentrator started operation in May of 2014. This plant was designed for an average of 63,500 tpd (70,000 stpd), increasing the total Morenci concentrator complex production to a nominal 113,400 tpd (125,000 stpd). The process flow diagram is shown below in Figure 1.The process consists of primary crushing feeding a coarse ore stockpile followed by secondary crushing operating in closed circuit with vibrating screen decks. The screen undersize feeds the first of its kind Metso hydraulic roll crusher (HRC) operating in a closed circuit with vibrating screens. The primary crusher is a Metso 60x110 gyratory crusher. Secondary crushers are Metso MP1250 Crushers with variable speed drives. Secondary crusher discharge is recycled to the dry screen feed bin and screened with oversize returning to secondary crushing and undersize feeding the Metso HRC3000. The product from the 3.0 meter X 2.0 meter roll crusher is wet screened with the undersize feeding the grinding circuit, which is comprised of two each 24-foot diameter by 40- foot-long variable speed ball mills running in parallel with each in closed circuit with a cyclone bank of 12 cyclones. The wet screen oversize is recycled to the HRC feed bin."

Jan 1, 2019

By D. C. Downing

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

Jan 1, 1973

By John Loui Porathur

Highwall Mining has been recently introduced in India. The first Continuous Highwall Mining extraction in India started operating at Ramagundem Opencast Project-II (OC-II) of Singareni Collieries Company Ltd. (SCCL) in December 2010. A new hybrid empirical and numerical modelling approach has been devised to design web pillars for the initial Highwall Mining sites in India, considering the complex geology, such as existence of thick seams and multiple seams in close proximity. This paper gives the scientific elucidation of a comprehensive design methodology adopted for the above mentioned Indian Highwall Mining sites. The design technology includes web pillar design for multiple seams using hybrid empirical and numerical methods, slope stability assessment, ground movement monitoring, and recommendations for conducting blasting operations in the vicinity of Highwall Mining extractions.

Aug 1, 2013

By Christopher Andreae

Years before iron and steel works were established at Sydney, several thriving although short-lived iron works operated in Nova Scotia. These furnaces reflected the general nineteenth-century North American experience with iron works. At the beginning of the century, small furnaces struggled to supply local needs. Charcoal was the principal fuel and water powered most furnace equipment. By the end of the century, a few huge primary iron and steel works dominated production for Nova Scotia and the rest of Canada. Two sites achieved prominence in the nineteenthcentury Nova Scotia iron industry: Londonderry and Ferrona (Fig. 1). Londonderry, the larger and longerlasting of the two sites, is today a small village on the south flank of the Cobequid Mountains, about 30 km west of Truro. Prior to the establishment of an iron works in 1849, no community existed. At the peak of operation in the 1880s, however, over 2600 people were located there. The second site, Ferrona, today is a mere crossroads on the map, about 10 km south of New Glasgow. Following the construction of a blast furnace there in 1892, a small village grew up around the furnace. But once the furnace was blown out in 1904, the population gradually drifted away.

Jan 1, 1999

By B. R. Maas

Processing material at a consistent rate through the continuous countercurrent decantation (CCD) thickeners presented a major bottle neck to unlocking additional value from one of the post-flotation streams at the Kansanshi processing plant. The manual operation of the thickeners making up the CCD train resulted in frequent imbalances and process upsets across units. The automation of CCD trains is notoriously tricky as the available manipulated variables are outnumbered by the parameters requiring regulation. The implementation of an advanced, auction-based, control philosophy to manage the movement of both slurry and solution inventory through the train addressed this parameter imbalance and lead to the stabilisation of the circuit. Since the commissioning of this control strategy: an additional 7 200 dmt/day (+36% throughput) of material can reliably be processed through the train, the number of monthly downtime events has reduced, and a saving of $354 000/month in reagent cost has been achieved. INTRODUCTION CCD operation Agitated leaching is a common method used in hydrometallurgy to extract a metal from its host ore. The host ore is initially finely ground to liberate the surfaces of the valued minerals and improve the kinetics of the leaching process. The ore is then contacted in an agitated tank with a lixiviant to dissolve the desired metal into the aqueous phase. The resultant slurry from the leaching process comprises of a solution pregnant in the metal salt and a barren ore. The first purification step taken after leaching is to wash the pregnant liquor solution (PLS) from the depleted ore. On the industrial scale, a set of between two to ten thickeners arranged in a countercurrent configuration is often used to carry out this separation (Perry & Chilton, 1973). The slurry is introduced at the head of the train and a wash solution at the tail. The two streams are pumped through each thickener countercurrent to one other. At each stage the residual PLS in the slurry is mixed and diluted down with the countercurrent overflow solution from the downstream thickener. The diluted slurry is fed into the thickener where the solids separate out through gravity sedimentation. The settled solids are channelled towards the underflow of the thickener by a rake mechanism and pumped downstream to the next thickener in the train. The outcome is the recovery of a PLS from the overflow of the lead thickener and a slurry of washed solids from the underflow of the tails thickener.

Jan 1, 2019

By Rong. G., T. Q. Lin, W. Du

Based on analysis of the evolutionary history of the valley in Baihetan, the mechanism of asymmetrical evolution, gradual migration-incision evolved from left bank to the right, is revealed in Baihetan river valleys. The process of in-situ stress evolution is carried out by using the Universal Distinct Element Code (UDEC). Consequently, the numerical results which indicate the main regulations of that stress field are as follow: (1) The phenomenon termed "high in-situ stress fold" appears in the bottom of the valley. With the maximum principal stress being 28-34 MPa, the stress increases significantly at a vertical depth of approximately 130 m. (2) The in-situ stress presents zonal distribution along the bank slope. It is apparent that the in-situ stress field consists of stress relaxation zone (SRZ), stress concentration zone (SCZ) and original stress zone (OSZ). The horizontal depth of stress relaxation zone varies from the left bank (roughly 200 m) to the right (about 120 m). Furthermore, the stress evolution of the left bank slope is studied. As a result, it is found that asymmetrical erosion contributes to the difference of the in-situ stress distribution as a critical factor, between the left bank and the right. And for an asymmetrical valley, the evolutionary process of in-situ stress field is a circular procedure, which includes the incision of valley, the accumulation of landslides and the migration of valley.

Jan 1, 2015

By John D. Godfrey

Precambrian Shield rocks, exposed in the extreme northeast corner of Alberta, provide the only possibility for a granitic building stone development in the province. Among a wide variety of granitoid rocks in the Shield, the Chipewyan Red Granite is one of the most favourable prospects. Geological mapping and exploration has revealed two prospective sites within a major pluton situated close to navigable water. Cleaned outcrop surfaces show clearly the pattern of joints and lithologic variations within the granite at prospective quarry sites. Other features include: basic dykes, quartz veins, and sheeting fracture zanes. Systematic orthogonally arranged fracture sets and the sheeting zanes are auributed to a tectonic origin. onsystematic irregular fractures are related to surface and nearsurface processes, such as decompression through unloading .

Jan 1, 1984

By R. W. Nice

Presently about 60% of the world's nickel resources are tied up with lateritic ores while about 25% of the world's nickel is produced from sulphides. Based on this the industry has to focus on improving lateritic nickel economics in order to maintain the high use of the metal worldwide. In 1997 three junior mining companies in Australia organised finance against all odds and commenced development of three separate nickel and cobalt extraction plants treating lateritic nickel ores. All three projects utilise similar pressure acid leaching (PAL) technologies while each has unique metal recovery technologies All projects have experienced numerous processing and maintenance related difficulties such that full ore throughput has been reached by only one operation after five years. This shortfall in performance has caused the owners considerable angst and financial pain. In 2000 Cawse went into receivership and was purchased by an international corporation. Recently, Bulong also went into receivership and has undergone an orderly shutdown, awaiting sale to a new buyer. Murrin Murrin has settled with its financiers and is in a position to operate as planned for many years forward. This paper will discuss a number of the technical difficulties that affect the ore preparation, PAL and solution treatment circuits of these plants. The objective is to identify the cause of some of the difficulties and propose possible solutions so that the next generation of lateritic operations can emerge as technically and, more importantly, economic successes. A number of these process improvements have been identified by the existing operators and in many instances have been or are being implemented into the existing operations.

Jan 1, 2004

By D. T. White

Pressure acid leaching of nickel laterite ores typically involves the production of an intermediate product that is releached and refined to pure nickel and cobalt products. BHP Billiton is developing the Ravensthorpe Nickel Project to produce up to 50,000 t/y of nickel via a mixed hydroxide intermediate, which will be refined at its Queensland Nickel (QNI) Yabulu Refinery near Townsville, Queensland. The hydroxide precipitation flowsheet has been adapted to process high magnesium ores through an atmospheric leach stage, eliminate iron(III) as jarosite and oxidise iron(II) during neutralisation. The neutralisation conditions are controlled to precipitate aluminium, chromium and silicon, and to ensure good solid-liquid separation. Soluble impurities such as magnesium are purged with the tailings stream and will be managed over the long term by crystallisation in evaporation ponds.

Jan 1, 2006

By H. J. Ni, M. Y. Huang, S. W. Chen

The effects of several fluxes on purification, microstructures and properties of A00 aluminium have been studied. The experimental results and analyses indicate that many cracks and large porosities exist in the surface film above the melt purified by C2Cl6 and that the film is floe and mostly composed of AhO3 and pure aluminum, which carries many carbon particles and AlCh not fully volatilized. And then over 50% of the all-melting residue is pure aluminum, which is one of the major reasons for high melting loss. Moreover, because of a mass of gas bubbles and a state of seethe, there exist many inclusions which size is under l0µm in the microstructure of A00 aluminum purified with C2Cl6 or fluxes containing C2Cl6- With this purifying method, the aluminum crystal grains are extended along the radius that was observed firstly and the average crystal size of A00 aluminum are about 100µm~150µm. In addition, small size inclusions have little affected on tensile strength and micro inclusions under l0µm have little affected on elongation.

Jan 1, 2006

By T. F. Pugsley, D. Gignac

"The historical background to the project dates back to the mid-30s with the discovery of surface sulphide showings in the Cape Smith-Wakeham Bay ultramafic belt. In the mid1950s, orderly exploration commenced with an extensive work program by Asarco, INCO, Lemoine, Falconbridge and Raglan Nickel Mines Ltd. on exploration permits. In 1966, Falconbridge and Raglan Nickel Mines interests merged. Extensive exploration, drilling, under- ground delineation of the Donaldson orebody and the construction of basic infrastructure such as camps, airfield, road links from Douglas Harbour to Donaldson and Katinniq, a distance of 60 km, were completed.Production project design at that time consisted of plans for a 50 000 mt per year nickel mining and concentrating operation, including a 2000 person community and smelter at Douglas Harbour. These plans unravelled in the mid-70s due to high capital costs, poor nickel market conditions and the realization that the Raglan orebodies were not large enough to economically support the construction of green field smelter and refinery facilities for processing Raglan production. Nickel market conditions in the late 70s and early 80swere generally poor, resulting in further delays on production plans.While recognizing the very high potential to discover increased tonnages of high grade(3% Ni) in excess of 20 million tonnes, the project was deferred into the late 80s when a serious re-evaluation of exploration potential occurred and the requirement to prove up additional reserves resulted in an underground exploration program at Katinniq covering the period 1990-1992."

Jan 1, 1996

By R. D. Brown

"AbstractOver the past five years, tax rates in the Canadian mining industry have skyrocketed upward across Canada, as both federal and provincial governments have sought to increase their share of mining revenues.However, the past few years have not only brought high tax rates to the industry, but also a number of important new federal and provincial tax incentives.In large part, these incentives ~ special credits or reduction in tax for carrying out specific exploration, processing or other activities - have helped to moderate the adverse effects of the higher tax rates and have provided inducements for exploration and processing activities which might not otherwise have been undertaken.However, the effectiveness of certain of these incentives can be questioned: our over-all tax structure now consists in large part of punitively high marginal rates with some extraordinarily generous but capricious tax reductions for specific activities and may not be in the best long-term interest of either the industry or the nation.A rational tax structure, with moderate and stable tax rates, together with reasonable incentives confined to activities specifically requiring them, could be a more effective spur to investment than the present tax and incentive jungleIntroductionIN THE YEARS since federal tax reform, the mining industry in Canada has faced a continued escalation in its tax burdens as federal and provincial governments have leapfrogged each other in imposing new and higher taxes on the industry. The result has been that marginal tax rates imposed on mining and processing activities throughout Canada have jumped to hitherto unparalleled levels."

Jan 1, 1977

By Benoît Plante

La mine Tio (QIT Fer et Titane Inc.) exploite à ciel ouvert un gisement d?ilménite massive depuis 1950, générant jusqu?à maintenant plus de 70 Mt de roches stériles potentiellement génératrices de drainage neutre contaminé (DNC), dont une partie est submergée dans le lac Petitpas, au nord de la mine. Si généralement l?ennoiement des rejets miniers a un effet bénéfique pour limiter la contamination des eaux, cela reste à prouver pour ce qui est des stériles générateurs de DNC. Des essais en réservoirs ont été réalisés afin d?évaluer la réactivité de trois différents types de stériles submergés, qui ont été choisis en fonction de leur teneur en ilménite. Afin d?évaluer l?impact de la matière organique sur la réactivité des stériles submergés, chaque type de stérile est étudié en immersion simple ainsi que combinée à des sédiments prélevés au lac Allard, à proximité de la mine, d?où l?eau utilisée dans les essais a aussi été prélevée. L?évolution des teneurs en Ca, Mg, Si et Ni durant les 8 premiers mois d?étude démontrent que les stériles immergés sont réactifs, mais l?impact de la matière organique demeure pour l?instant difficile à préciser. Tank tests on Tio mine waste rock The Tio mine (QIT Iron and Titanium Inc.) exploits a massive ilmenite ore as an open pit since 1950, producing over 70Mt of potentially contaminated neutral drainage (CND)-generating waste rocks. While the underwater disposal of mine wastes generally show a beneficial effect on water contamination, this method still needs to be approved for CND-generating waste rocks. Tank tests were realized in order to evaluate the reactivity in underwater conditions of 3 different waste rock types, chosen with regards to their ilmenite content. In order to evaluate the impact of organic matter on the reactivity of underwater waste rock, each waste rock type was studied in simple immersion and in combination with sediments sampled at Allard lake, located near the mine, where the water for the tests was also sampled. The evolution of Ca, Mg, Si and Ni during the 8 first months of testing show that the waste rocks are reactive underwater, but the impact of the organic matter is till hard to define.

Nov 1, 2008

Pilot plants for pressure hydrometallurgy represent special design and project execution challenges unique to the industry and to the pilot- and demonstration-scale. Pilot plant projects have different objectives and shorter timescales than commercial plant projects. Design considerations and strategies, and project execution methods that meet the special needs of pilot plant projects, are discussed. Specific guidance is given for the selection of appropriate pressure and temperature design points for pressure hydrometallurgical process equipment, and for the selection of materials of construction for pilot-scale equipment. The balance between the need for process similarity with future commercial operations and the realities of pilot-scale equipment is also discussed.

Jan 1, 2004

By Sigmund J. Andersen, Eva A. Mørtsell, Jostein Røyset, Randi Holmestad, Oddvin Reiso, Yanjun Li, Øyvind Paulsen, Calin D. Marioara

"With the purpose of increasing the extrudability of lean alloys, we reduce levels of the alloying elements Mg and Si in a 6xxx extrusion alloy. To avoid sacrificing strength, we investigate the compensating effect of smaller amounts of lithium and germanium, alone and in combination. Recent studies by atomically resolved high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) together with density functional theory (DFT) calculations have demonstrated that while Li replaces Mg, Ge substitutes Si in the columns in the hardening ß’’-phase. Several studies have shown that Ge replaces Si in other precipitates as well, and that both Li and Ge promote precipitation and can improve macroscopic properties, like strength and thermal stability. The scope of the current work has been to investigate and document the combined effect of the two alloying elements. Of the investigated alloys, the one containing both elements displayed highest hardness, corresponding with a significant increase in precipitate number density. We used HAADF-STEM to determine the extent of Li and Ge in the precipitate structures.INTRODUCTION The two most important alloying agents, with respect to age hardening of the 6xxx alloy series, are Mg and Si. In general, 6xxx alloys are formed into their final shapes by rolling or extrusion, before being age-hardened at elevated temperatures around 180°C. The hardening effect during this stage is due to the formation of metastable, semi-coherent, precipitate needles along the three < 001>Al directions generally following the precipitation sequence (Marioara, Nordmark, Andersen, & Holmestad, 2006): Supersaturated solid solution ? atomic clusters ? Guinier-Preston-zones (pre-ß”) (Edwards, Stiller, Dunlop, & Couper, 1998) (Marioara, Andersen, Jansen, & Zandbergen, 2001) ? ß” (Andersen, et al., 1998) (Hasting, et al., 2009) ? ß’ (Vissers, Huis, Jansen, & H. W. Zandbergen, 2007), U1 (Andersen, Marioara, Vissers, Frøseth, & Zandbergen, 2007), U2 (Andersen, Marioara, Frøseth, Vissers, & Zandbergen, 2005), B’ (Vissers, Marioara, Andersen, & Holmestad, 2008) ? ß, Si (stable)"

Jan 1, 2018

By D. F. VanDine

The phases of a typical exploration program for sand and gravel resources include: (1) collection and assessment of existing information; (2) air photo interpretation and remote sensing; (3) ground investigation and mapping; (4) sampling and testing; and (5) data storage, retrieval, analysis and presentation. Depending on the purpose, time frame and funding available for the study, these phases, and the various techniques used within each phase, will vary. Once a sand and gravel deposit has been located, defined in size and quality, and found to be suitable for a given purpose, it can then be classified as a granular resource.

Jan 1, 1984

By J. Stiksma, R. Kalanchey, M. J. Collins, G. Owusu, R. Raudsepp, K. R. Buban, L. A. Barta, L. Masters

This paper describes the results of testwork for the treatment of Ambatovy laterite by an acid pressure leach process, with recovery of the soluble nickel and cobalt values as mixed sulphide intermediate by precipitation with hydrogen sulphide, and subsequent refining of the mixed sulphide to nickel and cobalt metals. These process development studies were carried out primarily in 2004, as part of a bankable feasibility study for the Ambatovy Nickel Project.

Jan 1, 2004

By A. Torkian

Copper mining operations have increased in Iran in the past decades due to price increases and potential for creating jobs in developing countries. Iran consists of many copper mines. The mining operations have a positive economic impact on the region, but may also be the cause of adverse environmental effects. Environmental aspects and the health impact of respirable particulates on the communities and agricultural production in the immediate vicinities have been under scrutiny by the regulatory agencies to ensure sustainable development. The impact of an open-pit mine on the air quality and extent of particulate pollutant dispersion in different directions and times is the focus of this paper. The results of the modeling have been validated through ambient air monitoring. Monitoring stations were installed in different areas within the mine unit operations and around it including background areas where PM10 values were 7 µg/m3. Outside the Complex, particulate concentrations were monitored in 9 different stations and up to 25 km distance. Modeling of point, area, and volume sources was conducted using a 9- year meteorological database. The results showed that particulate quantity decreases rapidly below local standard value of 150 µg/m3 at 2.5 km around the mine and the main pollution is due to the crusher and tailings dump areas. Model outputs were compared to the actual values measured by the air quality monitoring network including villages and crop fields. High overall correlation of about 76% was obtained for most of the locations but lower values were reported for more complex terrain in the region. Remedial actions recommended included road water spraying and better management practices to avoid overloading trucks.

Aug 1, 2013