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By G. F. Vander Voort

Over the past twenty years, steelmakers have introduced improved practices for reducing the inclusion content of steels. The success of these practice changes can be monitored in a variety of ways. Chemical analysis of the bulk sulphur and oxygen contents provides a relatively simple means to assess the impact of these changes. However, microscopical test methods are still needed to assess the nature of the inclusions present. Traditional chartbased measurement methods have wide acceptability, and their data are well understood by both purchaser and producer for heat acceptance purposes. However, these methods do have inherent weaknesses which limit their usefulness for quality control, SPC, and database applications. Image analysis-based chart measurements are an improvement over manually generated chart ratings, but the data still do not lend themselves to databases and statistical comparisons. ASTM Committee E-4 on Metallography has developed a stereologicallybased image analysis standard test method, E 1245, which provides the necessary data in a form which is easily databased and analyzed statistically. This paper describes E 1245 and shows how data from different heats and melting practices can be compared statistically to ascertain valid test differences.

Jan 1, 1998

By H. C. Gunning

SOME small vanadium-bearing deposits on the west coast of British Columbia about 100 miles north of Vancouver are of interest for several reasons. They are of a type that is, so far as we know, unique. They are difficult to identify as being vanadiferous so that, unless they are described, other similar deposits could easily pass unrecognized. Furthermore, although none of them has as yet been proven to be of commercial proportions, no good reason is apparent why larger, and therefore valuable, deposits should not occur under similar geological conditions. The original discovery on Quadra island was made in 1932 and has been recorded by H. V. Ellsworth and H. C. Gunning (l). Since 1932, prospecting in the area has revealed other similar deposits, one about a mile south of the original and another some ten miles to the east, near Menzies bay on Vancouver island. The Quadra Island showings are a mile and a half north of the head of Gowland harbour, a small inlet that is easily reached by gas boat from Campbell river, about four miles to the southeast on Vancouver island. The deposits were examined by the writers in the spring of 1943 in connection with field work sponsored by the Department of Geology, University of British Columbia. We are indebted to Mr. G. A. Dirom and Mr. Lothrop, of Vancouver, for helpful data on the Menzies Bay deposits, and to Dr. V. Dolmage for making a brief trip to Gowland harbour and discussing the deposits.

Jan 1, 1944

By F. Logsch, H. Pempel, J. Markowski, P. Ay

"Due to the European Directive 2000/53/EC on end-of-life-vehicles, from 2015 on more than 95% of car materials have to be recycled. In order to recycle the materials back into the economic cycle, it is necessary to produce products with high quality and purity.Plastic components in cars, which are coated with metals by vapour deposition or electroplating, have a wide circulation (e.g., as cladding panel or trim strip for interiors and exteriors). In the end-of-lifevehicle recycling process, these plastic-metal composites are not considered in usual technologies (car shredder) and are not separated from Automotive Shredder Residue. These parts can be separated by optical or HF-detection sorting and then introduced to a specific treatment.Experiments with a specially developed bioleaching configuration showed that the thin coatings, which consist mainly of copper, nickel and chromium, can be removed efficiently from the polymer base materials by a bioleaching solution with Acidothiobacillus ferrooxidans as a leaching agent. The solution used was produced in special fermenters with a 9K-nutrient salt media. During the bioleaching process at 35°C maximum temperature, most of the copper is dissolved and the other metals accumulate as metal sludge. The bacterial cultures based on A. ferrooxidans are robust and resilient.After a 48-hour bioleaching period while the composites were stirred regularly with ventilation, the plastic particles were completely free from metallic coatings. The metal components are separated for further use: undissolved components (mainly Ni and Cr) are separated by decantation of the solution; dissolved copper recovey is carried out by cementation of copper. The cementated solid contains ~98% Cu, along with small amounts of other metals.With the bioleaching process, good separation and re-utilization of the metallic coatings is possible. The cleaned plastic parts were prepared by compounding for new applications with injectionmoulding."

Jan 1, 2016

By S. Southall, F. McCaffrey, F. Stober, M. Darini

Electrode Columns are commonly used in electric furnaces to deliver current and regulate furnace power to the smelting or melting process. Hatch has developed an innovative patent-pending system for lowering ("slipping") and/or raising ("back-slipping") the electrodes through an electrode column, without requiring the release of any clamping devices. All clamping forces are applied by springs. Unlike systems employing hydraulically applied clamping forces, (e.g., water bladders) the spring system is failsafe. Its inherent simplicity virtually eliminates the need for maintenance. The Hatch system is particularly applicable to Soderberg electrodes, and comprises two axially movable slipping clamps and a stationary power clamp, each of which apply a distributed, radial clamping force to the electrode. The magnitudes of the slipping sleeves' clamping forces and sequencing of their axial movements are selected such that the slipping clamps, in conjunction with the weight of the electrode, provide slipping or back slipping without release of any clamping force.

Jan 1, 2005

By O. Mejia

"As study was undertaken to investigate the relationship between mill liner wear and grinding energy efficiency and to assess the opportunity to control mill speed to improve energy performance as mill liner wears. The study involved analysis of plant operating data and liner wear profiles over time. The operating work index was found to be an effective tool to identify the decrease of grinding efficiency along the liner service. The plant data show that the mill grinding efficiency as determined by monitoring the operating work index, and throughput decreases as liner wears. However, efficiency and throughput can be maintained by either changing the liner more frequently or by increasing the mill speed. Two scenarios for increasing mill throughput were analyzed. The first one involves changing the liner before the efficiency drops and the second one requires increasing the mill speed from 75% to 79%. Both scenarios show financial benefits that can be used in mill operations.INTRODUCTION The analysis of the mill power draw is used in this study as a key parameter for comparing mill liner profile and its effect on mill performance. Current technology and simulation software used in the mining industry do not factor in the impact of liner wear profiles in grinding efficiency and mill throughput (Toor, 2013). To address this gap, this study provides an analysis of key factors affecting mill throughput and grinding efficiency: mill speed, ball loading, and liner profiles. Several years of plant mill operating data, published research papers, and MillTraj® simulation results are used to demonstrate that face angles impact grinding efficiency and throughput and that mill speed can be used to overcome this problem. Moreover, the liner profile wear analyses clarify a mismatch between actual and estimated power draw calculations."

Jan 1, 2019

By Link. Theo A.

Introduction Since the discovery of a major oil pool at Leduc, Alberta, on February 13th, 1947, the long spell of 'oil drought' in Western Canada is now being turned into an oil and gas flood which requires immediate action to obtain the optimum economic benefits. The Woodbend, Section 9, and Okalta extensions of the Leduc field itself have been established; the Redwater pool, lying thirty-seven miles northeast of Edmonton, has been discovered and is being drilled up, and the Imperial Schoepp No. 1 or Golden Spike discovery holds promise of something phenomenal in view of the 500 feet of oil-saturated coral-reef porosity whose areal extent is not known. Imperial Stanolind Barrhead No. 1, northwest of Edmonton, revealed the presence of oil in the Madison, and just recently Gulf N.J. Ellis No. 1, some sixty miles southeast of Leduc, found commercial production in the Leduc D-2 discovery zone. In addition to these Paloeozoic discoveries, gas and oil reserves have also been established in the Upper and Lower Cretaceous, which must be penetrated by all tests on the way through the geological column to the Devonian. If ever there appeared to be an index of 'things to come' in the oil industry, this is it. However, without these recent discoveries the picture in Western Canada does and always did, look very promising indeed. A brief survey of the geological setting in Western Canada is the object of this contribution.

Jan 1, 1949

By Shahram Tafazoli

ABSTRACT: This article presents a novel technology for sensing the size of rocks after blasting in hard rock mines. Blast engineers require rock size statistics to carefully adjust the blasting parameters. The rock fragmentation requirements vary depending on the ore type and crusher specifications. The most popular statistical parameters in the industry are the so-called P numbers (e.g., P80 and P100). A machine vision based system is introduced here for automatic image collection and fragmentation analysis of the material right inside the bucket or dipper of mining shovels. A heavy-duty camera provides the required imaging data to an embedded computer mounted inside the cab. A custom machine vision software continuously analyzes the captured bucket images and stores the suitable ones in local storage which are then fed to a Desktop software for automatic fragmentation analysis. This technology has been developed by Motion Metrics International and is commercially available as FragMetrics?.

Oct 1, 2009

By Shahram Tafazoli

This article presents a novel technology for sensing the size of rocks after blasting in hard rock mines. Blast engineers require rock size statistics to carefully adjust the blasting parameters. The rock fragmentation requirements vary depending on the ore type and crusher specifications. The most popular statistical parameters in the industry are the so-called P numbers (e.g., P80 and P100). A machine vision based system is introduced here for automatic image collection and fragmentation analysis of the material right inside the bucket or dipper of mining shovels. A heavy-duty camera provides the required imaging data to an embedded computer mounted inside the cab. A custom machine vision software continuously analyzes the captured bucket images and stores the suitable ones in local storage which are then fed to a Desktop software for automatic fragmentation analysis. This technology has been developed by Motion Metrics International and is commercially available as FragMetrics?.

Oct 1, 2009

By Shahram Tafazoli

This article presents a novel technology for sensing the size of rocks after blasting in hard rock mines. Blast engineers require rock size statistics to carefully adjust the blasting parameters. The rock fragmentation requirements vary depending on the ore type and crusher specifications. The most popular statistical parameters in the industry are the so-called P numbers (e.g., P80 and P100). A machine vision based system is introduced here for automatic image collection and fragmentation analysis of the material right inside the bucket or dipper of mining shovels. A heavy-duty camera provides the required imaging data to an embedded computer mounted inside the cab. A custom machine vision software continuously analyzes the captured bucket images and stores the suitable ones in local storage which are then fed to a Desktop software for automatic fragmentation analysis. This technology has been developed by Motion Metrics International and is commercially available as FragMetrics?.

Oct 1, 2009

By M. Saghaeian, R. Hejazi, Sheikhzadeh. V., A. Abazarpoor

"The morphology of iron ore concentrate particles is known to influence several properties of iron ore pellets, including drop number, compression strength, and reduction properties. This study aimed to determine why grinding methods and particle morphology influence green pellet properties. Particle morphology can be directly related to the grinding method: ball mill (BM) or high pressure grinding roll (HPGR). In this research, two iron ore concentrates, namely Gol-e-gohar and Ardakan, were ground by a BM and HPGR to produce a suitable Blaine value for pelletizing (nearly 1,900 cm2/g). Morphological features of particles were subsequently investigated by sieving and cyclone sizing for particle size distribution, the Brunauer-Emmett-Teller (BET) and Blaine methods for specific surface area (SSA) and scanning electron microscopy (SEM) for the evaluation of shape descriptors. It was concluded that HPGR resulted in generating a greater proportion of fine particles compared to ball milling. The BET results showed that the SSA of HPGR pellet feed was higher than that from the BM due to a greater proportion of cracks, indents and bulges and the creation of new fracture surfaces. SEM images processed by ImageJ software indicated that particles ground by the BM tended to be more rounded and less elongated than HPGR particles because of the breakage model of each method. To show the effect of morphology on the green pellet quality, green pelletizing was performed in a pilot pelletizing disc. The HPGR pellet feed had a higher drop number in comparison to the BM pellet feed, due to the angular and rough shape of the particles.INTRODUCTIONThe demand for fine or ultra-fine particles as feed material for ceramics, composite materials, and mineral processing is on the rise (Kotake, Kuboki, Kiya, & Kanda, 2011). The final concentrate of iron ore processing plants (filter cake) has a size range roughly between 0 and 300 µm, depending on the liberation of Fe containing particles (Meyer, 1980). In general, to produce a suitable pellet feed of appropriate quality, Blaine numbers of 1800–2000 cm2/g should be achieved (Van der meer, 2015)."

Jan 1, 2016

By E. J. Debicki

"At the 1992 PDAC Convention, Norman Keevil announced the formation of the Exploration Technology Division (ETD) of the Mining Industry Technology Council of Canada (MITEC). It was evident that base metal reserves in Canada were declining and that the cost of discovering a deposit in Canada was increasing. Coordinated research to develop new exploration technologies was required to discover the next generation of ore-bodies. The ETD was formed in response.The mission of the ETD is to contribute to the survival, profit, and growth of the Canadian mining industry by improving the efficiency and effectiveness of mineral exploration through development of innovative technology by man-aging and coordinating applied cooperative research. In addition, it is the intent of the ETD to become the principal agency by which cooperative research funds are transferred to researchers from the mining industry. The division is industry driven, industry funded and industry managed.The ETD’s Three-Year Plan has focussed80% of its research funds toward two objectives, improving the efficiency of exploration for VMS deposits and establishing the parameters necessary to discover the next Hemlo deposit. The remaining 20% is allocated to other projects, with the current emphasis on geophysics.In 1995, corporate members total twenty-three major mining companies accounting for90% of the exploration expenditures in Canada. The ETD is currently managing ten cooperative research projects totalling $4.6million. Other projects, estimated at $1.6 mil-lion, are currently under development."

Jan 1, 1996

By C. R. Stelck

"AbstractThe Cardium formation of northeastern British •Columbia •contains an erosional unconformity that becomes progressively more severe northward until, •at Liard river, the stratigraphic hiatus eliminates the underlying Lower •Cardium sandstone, the Kaskapau formation, and the upper Dunvegan sandstones. The area of unconformity roughly coincides with the distribution of the continental facies of the earlier Dunvegan formation. Along Wapiti river, the zone fossil Scaphites ventricosus Meek and Hayden is found in the Bad-heart member of the overlying Wapiabi shale; Scaphites :preventricosus. Cobban marks the base of the Wapiabi shale; Scaphites cf. corvensis •Cobban is found in the middle shale member of the •Cardium formation. The log of the Red-Willow No. 1 well shows close similarity to the outcrop sections south of Wapiti river. The Cardium formation is mainly late Turonian in age. Two other pre-Cardium Turonian sands of north-eastern British Columbia are named the Wartenbe and Tuskoola sands.IntroductionTHE Upper Cretaceous Cardium (Bighorn) sandstone formation of the Foothills of northeastern British Columbia carries within its formational limits an erosional unconformity. The unconformity decreases to the southeast, becoming in immediate shoreline regions, now under the plains, a minor diastem. Such diastems, or stratigraphic intervals of non-deposition, occurring in the shallow unda-zone are paralleled in the deeper portions of the unda-zone by the phenomena of sub-aqueous winnowing. '.This winnowing and re-working •at critical depths creates sand areas with porosity."

Jan 1, 1955

By Rodnei Graça, Jorge Silva Bettencourt, Lena Virgínia Soares Monteiro, Baruch Spiro, Tolentino Flávio De Oliveira

Abstract - The Vazante Mine is located in the Vazante District, the largest zinc district in Brazil. The Vazante deposit consists dominantly of an unusual willemitic ore. Small sulfide bodies are tectonically imbricated with the willemitic ore, within the Vazante shear zone. Structural styles of deformation and petrographic and isotopic evidence indicate that willemitic mineralization and deformation occurred synchronously during the Neo-Proterozoic. Various generations of hydrothermal veins and hydraulic breccias may pre-date, accompany and overprint the mineralization. Ore-formation temperatures are deduced from stable isotope geothermometry and mineral chemistry of both sulfide bodies and willemitic ore. Temperatures during the main stage of mineralization range from 206°C to 294°C (willemitic ore) and 317°C (sulfides), and reflect the prevailing metamorphic conditions within the shear zone. The fluid from which the gangue minerals of the sulfide bodies precipitated (at 250°C) had an oxygen isotopic average value of ?18O = +19.4‰. This value appears to reflect the interaction of metamorphic fluid with the carbonate rocks of the Vazante formation. At 250°C, the fluid in equilibrium with the vein mineral phases and willemitic ore assemblage exhibits a uniform oxygen isotopic composition, with an average value of ?18O = +11.5‰. The positive linear covariance of ?18O and ?13C ratios of the carbonates is most likely due to the mixing of metamorphic and meteoric fluids. The ?34S values of sulfides indicate a direct crustal origin for the sulfur. It is suggested that the sulfur is largely derived from pre-existing sulfide bodies and has been transported by metamorphic fluids. The willemitic ore may have originated from the precipitation of metal in sulfur- poor fluids under oxidized conditions, within the Vazante shear zone.

Jan 1, 1999

By Ben D. Thompson

Cemented Paste Backfill has proven to be of critical importance to the operation of a number of Canadian mines, primarily due to the rapid backfilling rate this method permits. In order to improve the efficiency of this backfill system (i.e. optimize binder contents, fill fence design, and the employment of two stage filling strategies) there is a requirement to better understand its geomechanical behaviour. In response, in-situ experiments have been conducted in long-hole stopes to quantify the evolution of total earth pressures and pore pressures at a series of instrumented points within both the core of the backfill and close to fill fences. The deflection of fill fences as a result of paste loading has been measured and additional instrumentation has also been employed to measure cement hydration, negative pore pressures, and blasting induced vibrations within fresh and cured paste backfill. Installing geotechnical instrumentation within an open long-hole stope can be an extremely complex procedure and this paper details the methods that have been successfully employed. Preliminary results are presented, and the pressures induced by backfill with differing binder contents, at a number of different in-stope locations are considered.

May 1, 2009

Delivering Our Products On any given day in North America, 80 kilometers of rail cars are engaged in moving our product. Global Customer Base Our business accounts for more than 30% of all bulk goods moved through the Port of Vancouver

May 1, 2006

By B. D. H. Knights, N. B. du Preez

The recovery of the economy of the Democratic Republic of Congo has allowed for the rapid increase in production of copper from this region, while the increased price of cobalt continues to support the recovery of that country’s economy. This has enabled the modernization of the process technology used, particularly the change from direct electrowinning of copper to solvent extraction-electrowinning. With this change has come a variety of technical challenges in optimizing the recovery of cobalt from these sources. In this paper, we discuss aspects of the flowsheets for the production of cobalt from the ores of the DRC and Zambia, highlighting the technological improvements that have been made. Following this description of the practice, we assess the challenges of further improving the recovery and purity of cobalt from these sources. INTRODUCTION The African Copperbelt (Figure 1) is by far the biggest producer and holds the greatest reserves of cobalt (Sheed, 2015). However, the ores of this great mining region are extracted primarily for their copper content, and cobalt is a by-product. The ratio of copper-to-cobalt is between 6 and 20 to 1, with the ores from the DRC richer in cobalt than those from Zambia. The overall supply of cobalt, shown in Figure 2, is increasing due to an increase in demand for its use as a battery material. Cobalt is used in superalloys, hard metals, pigments, catalysts magnets, tyre adhesives, lithium-ion rechargeable batteries, and wear-resistant coatings, amongst others. Although these generic categories persist, Figure 3 shows how the relative usage of cobalt is changing due to the uptake of electric vehicles in China and Europe. Cobalt is a key element in lithium-ion batteries, and because it is widely anticipated that electric vehicles will be legislatively encouraged, it is anticipated that the demand for cobalt will rise. This anticipated increase in demand resulted in an increase in the price for cobalt, to which suppliers responded over-eagerly, and the price has dropped dramatically in the first few months of 2019, as shown in Figure 4. However, there is a clear cycle of price peaks in cobalt’s history.

Jan 1, 2019

By Andrew Bamber

The mining and beneficiation of minerals is the second largest end-use of electrical power on the planet, and comminution is by far the largest single contributor to this. Several jurisdictions, including British Columbia, have, in response to concerns about greenhouse gas emissions and climate change, adopted energy conservation legislation, including carbon taxes, carbon trading and conservation incentive schemes. Key to achieving conservation objectives is firstly an understanding of usage metrics across the various unit operations in the sector, and secondly an understanding of the conservation potential represented by available technologies and approaches in reducing end-use. This paper presents the results of a recent utility-funded study on energy use metrics and conservation potential at large open pit mines which are typical of the sector in BC.

Aug 1, 2013

By C. Mills, A. O. Burt

"The paper examines the role of gravity concentration in both an historical context and within the modern mineral processing industry. It discusses the principles of the process on both a theoretical and practical level. The importance of more mineralogy and its effect on the choice of the wide range of equipment available is discussed. The paper concludes with a discussion on the relative merits of gravity concentration with other forms of processing.IntroductionIt is an unfortunate, albeit popular, misconception among otherwise enlightened engineers in the mineral processing industry that gravity concentration was a process developed in the dark ages, perfected in the middle ages, and abandoned in the modern ages.Gravity concentration was developed in the dark ages - long indeed before that. Agricolau: cited examples of gravity concentration, crude examples admittedly, being practiced over 3000 years ago. However, gravity concentration is not dead. Far from it. As recently as 1978 it was reported that the total mineral tonnage treated by this process in the United States was greater than that processed by flotation. Coal represents the bulk of the or e treated by gravity separation in the U.S.A., with iron ore representing a major portion of the balance."

Jan 1, 1985

By Dillon. Patricia

Business Growth ?Coal ?Targeting 30 million tonnes by 2013 compared to 19 million tonnes produced in 2009 ?Expanding Energy Business unit (Oil Sands) ?Copper -Strong growth potential for existing operations and development projects ?New gold strategy recently launched ?New markets for zinc Need to retain existing and attract new employees to support growth Engaged Employee ?Has a positive attitude towards the organization and its values ?Is a person who is fully involved in, and enthusiastic about, his or her work Engaged employees are more likely to stay with the organization.

May 1, 2010

By Bétournay. M. C.

Advantages ?Safety ?Health ?Rapid, continuous development, productivity ?Stope dilution reduction Disadvantages ?High cost and long time for equipment development ?Hard rock mining condition limitations ?Size of equipment ?Equipment set-up time, down time ?Performance does not meet financial return targets ?Drill and blast retains advantage in cost, productivity, capital investment, application flexibility ?Stress accumulation issues in deep mining, ground support and material handling issues in weaker rock

May 1, 2009