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By B. Wasmund, M. Parravani, M. Jastrzebski, Z. Coull

"One of the main drivers of overall profitability of pyrometallurgical vessels is refractory lining campaign life. Increased economic pressure to improve vessel life requires innovative solutions to the problem of refractory cooling. Hatch has recently developed a high-intensity, waterless cooling system that bridges the performance gap between external shell cooling and internal water-cooled copper elements. External shell cooling has a limited effectiveness in protecting the refractory lining, because it is thermally insulated from the hotface of the lining by its thickness. This situation does not improve until the lining itself has become worn near the end of the campaign. The patented technology developed by Hatch overcomes this problem by positioning high-velocity air-cooling channels within the lining, closer to the hotface where the cooling benefits can be realized throughout the entire duration of the campaign. The current paper presents the development and application of Internal Air Cooling technology as well as results from the pilot campaign in an operating commercial vessel. Various adaptations for this novel, cost-effective and inherently safe system are also discussed."

Jan 1, 2015

By A. Aubin, H. Yang, G. Zaluski

The Athabasca Basin of northern Saskatchewan and Alberta is an exceptionally rich metallogenic region, hosting more than 2.8 B lb U3O8, of which over 927 M lb U3O8 have been mined out since extraction first started in the late 1970’s. A detailed compilation of several empirical features of 85 deposits located within the basin was conducted in order to understand the distribution and variability of the geological characteristics of the mineralization and its associated alteration. A new empirical classification was devised based on four parameters: 1) geometry of the mineralization (dimensions and relation to the unconformity surface), 2) size, grade and metallurgical complexity of the mineralization, 3) lithostructural setting, and 4) extent and nature of associated alteration haloes. This compilation defines the footprint characteristics of the Athabasca Basin deposits, which guides decision-making processes from early exploration and discovery to resource expansion and extraction.

Jan 1, 2020

By Zhiqing Zhang, Changyun Chen, Qing Liu, Lin Lin, Zhihong Jia, Guangjie Huang, Lipeng Ding

The effect of interrupted quenching (IQ) treatments on natural aging and bake hardening response of Al-Mg-Si alloy was investigated by hardness measurements, tensile test, differential scanning calorimetry (DSC) and transmission electron microscopy (TEM). The results show that interrupted quenching at 100oC could effectively suppress natural aging and improve bake hardening response. The optimized interrupted quenching treatment is 100oC for 45min, which gives the alloy a relatively low T4 temper strength and higher bake hardening response. The formation of highly dense cluster(2) during the interrupted quenching could be the reason for suppressing the natural aging and accelerating the precipitation of ß? phase during the paint bake treatment. In addition, interrupted quenching at higher temperature (170oC) results in unfavorable properties in both T4 temper and paint bake treatment. The formation of large precipitates is responsible for these undesired effects.

Jan 1, 2015

By M. Pearson, L. Zunti

Pressure vessels in hydrometallurgy and many chemical process industries throughout the world require the use of specific lining systems to protect the parent vessel materials from corrosion and/or abrasion. Typically, these lining systems are required for processes that are corrosive and operate at elevated temperatures. Two basic lining system types arc: 1) refractory linings in conjunction with an impervious corrosion resistant membrane, and 2) metal-clad vessels consisting of titanium or other corrosion resistant metal bonded to a carbon steel shell. Operating conditions play a key role in selecting the type of lining system to be utilized for a specific application. Lining systems in turn have an impact on the process vessel size, which ultimately affects the capital cost of the vessel. The capital costs for each type of lining system must be considered for each application, as well as maintenance concerns, quality control, and delivery. It is clear that operating conditions play a key role in the final selection of lining systems utilized for specific projects based on initial capital cost, life-cycle maintenance costs, and overall service life. This paper will examine the fundamentals of each lining system, their inherent technical strengths and weaknesses, and present relative cost comparisons for each lining system as they apply to specific operating conditions and vessel sizes.

Jan 1, 2004

By D. Jean Hutchinson, Mark Diederichs

"Cable bolts are an important support component in modern underground mines. If an optimized cable bolt system is to be achieved, it is insufficient to focus on cable bolt layout design or on cable bolt installation in isolation. Cable bolt support, like all engineered systems, requires a holistic approach, encompassing integrated elements of design, implementation and verification. The “Cable bolting Cycle” described in this paper incorporates these components along with related tools and procedures which should be used together to ensure effective and efficient cable bolt support.Design involves the consideration of demand, capacity and constraints as outlined in this paper. The demands imposed on the sup-port system by the rock mass response to excavation under the combined action of stress and gravity must be matched to the capacity of the cable bolt array. The cable bolt system capacity is a function of the component strengths of the steel strand and the bond (load transfer) and by the deformation response and retention characteristics of the system. The design is bounded by operational and economic constraints.Implementation of the cable bolt array can then proceed and must include appropriate protocols of communication, training and quality control, in addition to both general and site specific installation procedures. Implementation will be discussed as the sum of these components.Implementation of the cable bolt array can then proceed and must include appropriate protocols of communication, training and quality control, in addition to both general and site specific installation procedures. Implementation will be discussed as the sum of these components.The information presented in this paper represents a very abbreviated version of much broader concepts, procedures and design charts, presented in a practical cable bolting handbook by Hutchinson and Diederichs (1996)."

Jan 1, 1996

By Lloyd W. Trevoy

Titanium and zirconium heavy minerals occur in the tailings streams from processing plants which use the hot-water extraction process for recovery of bitumen from tar sand. In a research program conducted by Syncrude Canada Limited, the crude tailings stream was upgraded to produce quality zircon and titanium mineral products. To process the tailings through conventional upgrading equipment, bitumen residues must first be removed from the mineral grains. Then, by gravity separation, fines and coarse sand grains were removed and a 71% heavy minerals concentrate was prepared which was further separated by high-tension equipment into zircon and titanium minerals concentrates. The zircon concentrate was upgraded by gravity, magnetic and high-tension cleaning to produce a high-quality 98% zircon product. The titanium minerals concentrate was separated into rutile, leucoxene and ilmenite fractions. Heavy minerals distribution in tar sand drilling core samples has been evaluated for various locations on Syncrude Lease 17, and expected annual production levels of heavy minerals have been estimated. A preliminary evaluation has been made of the potential for zircon, leucoxene and rutile production and for further upgrading of ilmenite and leucoxene to synthetic rutile for titanium dioxide pigment production.

Jan 1, 1978

By W E. vanSteenburgh

The Polar Continental Shelf Project was initiated in 1959 to provide an administrative and logistic vehicle for research in the physical sciences of the land, sea and channel area of the Arctic Archipelago. Most of the scientists are supplied on secondment from the professional branches of the Department. The yearly expeditions number some eighty scientists and sub-professional staff, and they are supported by a fleet of fixed-winged aircraft and helicopters. Accurate positioning is obtained by the use of a Decca Lambda navigational system which is moved as the area of interest is shifted. The Project is designed to accommodate not only physical scientists, but to provide facilities for other scientist who may have an interest in the area under study. The main research scope of the Project includes topographical surveys, hydrography, oceanography, geology, including marine sedimentary studies, gravity, magnetics, seismology, glaciology and geography. The Polar Continental Shelf Project was initiated and recommended by the Committee on Northern Development in 1958.

Jan 1, 1963

By M. M. C Jiménez, D. C. Buzzi, D. C. R. Espinosa, J. A. S Ténorio, G. F. R Oliveira

In this work the extractive and selective capacities of solvent extraction synergistic systems to recover nickel and cobalt were evaluated. The liquor used was from the high pressure acid leaching process (HPAL). Initially the industrial liquor, processed from lateritic ores, was analyzed to identify the concentrations of the metals. Experiments of synergistic solvent extraction were performed later. The extraction liquid-liquid was carried out with a mixture of Cyanex 272 (CY) and Ionquest 290 (IQ) extractants. The process was executed with the temperature of 65 ºC, pH of 5.2 and the ratio aqueousorganic 2:1. Systems of 80% kerosene and CY 20%, CY 16% - IQ 4%, CY 12% - IQ 8%, CY 8% - IQ 16%, CY 4% - IQ 16%, IQ 20% were studied during 20 minutes. The results of this paper showed that the mixture of these two extractants doesn’t improve significantly the recovery of nickel and cobalt from liquor.

Jan 1, 2014

By A. E. Moss

"IntroductionTHE WORLD-WIDE search for iron ore has been vastly accelerated during the past fifteen years .and Canada is playing a most prominent role in this prospecting boom. During this period, the search for .and development of iron ore deposits in Canada bas proven eminently successful and there is every indication that exploration will continue to be active for many years.This paper has been prepared primarily for the information of those who have bad little or no experience in iron ore exploration. For convenience, it is divided into three parts: ( 1) a brief discussion of the marketing of iron ores, with special reference to Canadian production; (2) a summary of the main features to be considered when prospecting for or evaluating a potential iron ore deposit; and (3) an outline of the methods and procedures used in the search for the direct-shipping iron ores in the Quebec•-Labrador iron ore field.The Iron Ore MarketDue to the tremendous tonnages of high-grade direct-shipping iron ore indicated in the iron ore fields of the Quebec-Labrador and Steep •Rock areas, it might be assumed that there would have been a sharp decline in iron ore prospecting in this country. On the contrary, the development of these two major fields, which must be classed among the world's greatest, has been responsible for much of the current activity. The search for high and medium grade magnetite deposits is being• conducted in many parts of the country and a number of these have reached the development stage. Production is being expanded from the known fields, such as Wabana in Newfoundland and Michipicoten in Ontario."

Jan 1, 1955

By Henry C. Knight

A number of improvements in the techniques of budgetary control have been developed in the 1970's. The most significant of these is zero-base budgeting. This procedure is a marked improvement, because it overcomes some of the key weaknesses inherent in most traditional approaches to budgeting. It incorporates techniques and disciplines which improve the quality of both the budgeting effort itself and the documents that most senior managers will need to evaluate. The end result is a budget that establishes and improves cost effectiveness. This budget is based on resource allocations using cost-benefit criteria and on a system of prioritization for making funding choices. Zero-base budgeting is applied only to costs and expenses that are not conducive to control using industrial engineered standards. Therefore, the benefits attributed to zero-base budgeting will only hold true for administrative, selling, exploration, safety, fire protection and overhead, and other indirect types of costs and expenses. It is in this context that the question of its attractiveness for the mining industry is dealt with.

Jan 1, 1978

By B. K. Mishra, Subrat Kumar Padhy, B. C. Tripathy, I. N. Bhattacharya

Manganese is a difficult metal to electrodeposit due to its high electronegativity and continues to possess unique process challenges. Manganese deposits of high quality are electrodeposited on 316 grade stainless steel from sulphate solutions in the presence of organic additives such as tetra ethyl ammonium bromide (TEABr), tetra propyl ammonium bromide (TPABr), and tetra butyl ammonium bromide (TBABr). The concentrations of these additives were examined over a relatively broad range to evaluate their effect on current efficiency, specific energy consumption and deposit morphology of the electrodeposited manganese metal. A maximum current efficiency of 68% was achieved in the presence of TEABr in the bath. X- ray diffraction studies revealed that (330) (411) planes were the most preferred planes of crystal growth during manganese electrowinning at a current density of 500 A/m2 resembling alpha-manganese irrespective of the nature of additive. Scanning electron micrographs showed smooth and uniform deposit morphologies when manganese was electrodeposited in the presence of TEABr.

Jan 1, 2014

By D. E. Deegan, G. Holcroft, T. P. Johnson

"The rising cost of extracting metals from existing traditional deposits, increasingly stringent environmental regulations and a greater awareness of corporate social responsibility issues are all factors in stimulating the examination of mine tailings and small-scale alluvial deposits as a potential source of new raw materials. Furthermore, despite tougher economic times the demand for commodities remains strong, in no small part as a result of the growth of the world’s emerging economies.This combination of social and economic factors looks set to continue in the long term which will encourage greater recovery of materials from previously ignored sources such as mine tailings and ores from alluvial deposits.An expansion in the recovery of useful materials from mining-related activities is likely to require the use of robust and innovative techniques that have a built-in degree of future-proofing; DC plasma technology is one such technology.As a result of its ability to separate the valuable metal and minerals from the waste material while destroying hazardous compounds, Tetronics’ DC arc technology offers an alternative approach to resource recovery from a wide range of mine ores. Harmful cyanide compounds and the vast quantities of water used in conventional hydrometallurgical processing are avoided when plasma processing is adopted. DC arc technology also brings additional benefits, including: the extremely effective destruction of organic materials, the conversion of the inorganic material into a re-useable aggregate and the high tolerance of the process to fine and dusty materials. This paper presents details of Tetronics’ DC arc technology as one of the key pyro-metallurgical solutions available for the recovery of valuable materials from traditional mine ores and tailings, as well as giving specific examples of how the technology has been successfully employed in the recovery of enriched slags, ferroalloys and other metals."

Jan 1, 2016

By Avi Nanda, Robert Brandt, Alex Piatkiewicz, David M. Jones

In 2010 the United States Environmental Protection Agency (UESPA) revised the National Ambient Air Quality Standards (NAAQS) by lowering the permissible value to a 1-hour average SO2 concentration of 75 ppb. In 2012, the USEPA designated the Miami area as non-attaining for the new SO2 NAAQS. A number of options were studied to assist in bringing the Miami smelter into attainment with the new standard. The chosen solution included: Installation of a large tertiary hooding system over the converter aisle; Hooding of the anode vessels and treatment of the anode gas in a baghouse; Installation of a large 2,325,212 Nm3/hr caustic scrubber to treat the captured converter fugitives and anode off-gases; Installation of a secondary ESP for the tapping fugitive off-gas treatment system; and the continuous scrubbing of all acid plant tail stack gases. The modifications have reduced smelter SO2 emissions by 85%, achieving a world class SO2 stack emissions rate of 0.45 kg of SO2/tonne Cu. INTRODUCTION The Freeport McMoRan Miami smelter has been previously described in literature (Steinborn, Pasca, Sallee, Binegar, Bhappu). For the sake of brevity a brief description is given here. The Miami smelter is located 129 km east of Phoenix, Arizona near the town of Miami, Arizona. The smelter was established in 1915 and has undergone a number of process upgrades and modernizations over the years. The present smelter consists of an Isasmelt furnace, an electric settling furnace, four Hoboken converters, two anode refining vessels & one casting wheel; and one double contact sulfuric acid plant. Concentrates are railed & trucked to Miami from four Freeport McMoRan mines located in Arizona & New Mexico. The wet concentrates, typically containing 10% H2O with a Cu/S ratio of 0.85, are smelted in an Isasmelt furnace to a matte grade of 58%. The entire output from the Isasmelt is laundered into an Elkem electric furnace (originally installed in 1972 as the primary smelting furnace) for separation into matte and slag. Slag containing 0.85% Cu is skimmed from the electric furnace and discarded. Molten matte, containing 60% Cu, is tapped from the electric furnace and processed in one of four Hoboken converters to produce blister copper. Two anode refining vessels further refine the blister copper before the final product is cast on a single, 30 mold, casting wheel. All of the anodes produced at Miami are shipped to the Freeport McMoRan electrolytic refinery in El Paso Texas for refining into cathode copper. Smelter off-gases from the Isasmelt, electric furnace and Hoboken converters are combined and treated in a double contact acid plant to produce sulfuric acid. Acid produced at Miami is internally consumed at Freeport McMoRan mines in the region.

Jan 1, 2019

By T G. Callcott

Australian coking coals are either class 434<tlj534<2l, at Port Kembla, or 634<3> at Newcastle. The former yield good blast-furnace cokes; the latter yield poor ones. However, increases in conventional strength indices, by methods applicable with normal coking ovens, seem unlikely to be economically attractive. Characterization of the coals has enabled an "economic" blend to be developed in the Newcastle area, and this has affected mining, preparation and handling operations. Coking studies have led to a specification for the making of strong coke, especially from the high-volatile Newcastle coals. Continuous coking studies, developed from the efforts to make very strong coke, have taken two directions. Firstly, coking thin layers of coal on strands; secondly, coking, in various types of vessels, compacts of coals with or with-out the inclusion of non-coking coals, iron ores or other inert materials. Gas, "sand" and hot metal coking have been tested for use in compact coking. Particular attention has been paid to pellets of coal and ore. The probable industrial problems in adopting any of the ideas are presently being examined.

Jan 1, 1963

By F. Ebbutt

The copper-bearing waters now treated successfully at Britannia for the recovery of their copper content are almost entirely derived from what is known as the Fairview mine; this was the first extensive copper producer of the Britannia ore-bodies, and consisted of a number of almost parallel veins, carrying good copper values, the ore consisting of chalcopyrite and pyrite in a quartz gangue. These veins occur in what is known as the ?Britannia shear zone&apos; (Schofield, S. J., G.S.C. Sum. Rept., 1918, Pt. B), developed for roughly five miles in a roof-pendant in the well-known Coast Range batholith. This .pendant is made up of Palxozoic rocks known as the &apos;Britannia Formation&apos; (LeRoy, O.E., Portion of Main Coast of B.C. and Adjacent Islands; G.S.C. Memoir No. 996, 1908). These consist of dark carbonaceous slates, quartzites; and tuffs or basic flows, and within them are large quartz porphyry siJls. These Britannia rocks are sheared and altered, the resultant rock being a fissile quartz-sericite or quartz-chlorite schist. The mineralization invariably occurs in this chlorite schist, which in the more productive areas has mottles or blobs of chlorite developed. A narrow, though persistent, band of grey slate forms the footwall of the productive portions of the shear zone.

Jan 1, 1928

By H. T. Kennedy, D. L. Flock

"The project described in this pa-per was undertaken to provide a more thorough understanding of the effect of contamination by drilling fluids on the electrical properties of porous systems. The basic work per-formed was filtration tests on both consolidated and unconsolidated sands and the determination of their resistivity profiles with the aid of screen-type electrodes spaced at convenient intervals along the core.Four drilling fluids were selected, ranging in resistivity from 447.0 ohm-cm. to •5.76 ohm-cm. The permeability of three unconsolidated and four consolidated cores, on which resistivity measurements were made, varied from 1,257 md. to 4,560 md. Five additional cores with permeabilities as low as 49 md. were tested to investigate the effect of permeability on the depth of invasion of drilling fluids.The effect of drilling fluid invasion on resistivity profiles was determined on cores containing brine only, and on those containing 80 to 90 per cent oil and 20 to 10 per cent brine. The study included measurements of (a) clay content of different sections of the core, (b) saturation of the invaded fluids and oil in different parts of the core, and ( c) changes in resistivity as a result of gravitational re-distribution of fluids and diffusion of electrolytes.The data showed that the resistivity of an invaded core is, as was expected, controlled by the resistivity of the filtrate, the resistivity of residual core water, the resistivity of the clay particles, and the amount and distribution of the filtrate, clays, residual oil, and brine. In most cases there was a significant increase in resistivity owing to the presence of clay solids which had invaded the core. The change in resistivity, as a result of the diffusion of salts, was substantial after a period of five hours. There is evidence in some cases that the residual oil and core water saturations of the unconsolidated cores, after substantial invasion, are very low, indicating almost complete displacement by invading fluid."

Jan 1, 1959

By L. W. Krahenbil

The programmable Logic Controller (PLC), at its present stage of evolution, is now considered as a mature control system. The PLC combines the solid-state reliability of hardwired logic and computer control systems with the simplicity of a relay ladder logic. Relay symbolic programming through a function-oriented keyboard provides a means which plant personnel can easily become accustomed to work with. In a large coal facility, it is shown that the control engineer can provide improved control flexibility with the advanced capabilities of the PLC.

Jan 1, 1979

By Cris Sideco

This paper describes the concentration processes of the Sullivan. Concentrator, including crushing , transportation, sink-float, grinding , flotation and dewatering. Handling of hot muck has had a deleterious effect on most of the processes, resulting in significant operating problems and poorer metallurgy. These problems are described -in detail. THE SULLIVAN CONCENTRATOR is situated in Kimberley, high up in the Purcell Range of the Selkirk Mountains, at an elevation of 3,600 feet, approximately 4 miles from the Sullivan Mine (see Fig. 1). The original plant went on stream on August 23, 1923 at a designed capacity of 2,500 tons per day. This has been increased in stages to its present rated capacity of 11,000 tons per day. The latest stage was in 1949, when several major projects, including the underground crushing plant, the sink-float plant and the installation of a rod mill, were completed. Some 112,800,000 tons of ore have been treated in this concentrator to November 1975. The plant started on a 48-hour/ week schedule, but was reduced to 44 hours/week in October 1946 and down to 40 hours/week by the end of 1949. Except for a 6-month period in 1952 when the mill operated continuously, the 40-hour/week, Monday to Friday schedule was in effect.

Jan 1, 1977

By R. J. Mitchell

"High narrow backfills of significant strike length approach the stress conditions associated with a free standing wall but this lower bound design approach is not considered efficient for earth structures. This paper considers the design of high narrow backfills using upper bound limit analysis, retaining wall theory with backfill arching and centrifuge model tests. Complex toe support situations pertaining to operational factors at Falconbridge&apos;s Lockerby Mine are investigated. It is shown that the susceptibility of high narrow fills to toppling is much lower than anticipated from the retaining wall analysis and that toppling can be avoided by a suitable toe support. It is also concluded that adhesion between the fill and an adjacent pillar can markedly increase the stability of the fill. INTRODUCTIONFalconbridge&apos;s Lockerby Mine pillar projects will expose cemented tailings backfills to heights (H) up to 55 m. The exposed backfills may have strike lengths (L) greater than the heights but are relatively narrow, having widths (w) of up to 12 m. The bulk cement content of the fills varies from 8.3% (12.1 T:C) to 3.0% (33.1 T:C). Exposed faces may have up to a metre of overhang due to stope overblasting, as shown in Figure 1. These fills have a solids specific gravity of close to 3.0 and were placed at a pulp density of about 68%. The tailings have a fairly uniform grain size with 32% less than 0.075 mm (200 sieve) and about 12% slimes (less than 0.02 mm sizes). The fill exposed by early pillar removal will be backed by adjacent, near vertical, ore pillars. Future pillar removal may expose similar fills which are not supported by an adjacent ore pillar but which will be backed by either an open void or by uncemented backfill. Furthermore, these fills may be undercut when the pillar slot is driven, further reducing stability (case 3, Fig. I) or a wedge could be left to help support the fill (case 2, Fig . 1). This paper presents limit equilibrium analyses for these various backfill conditions in a 22: 1 T:C fill and com- pares the results to data from centrifuge model studies at a scale factor of A= 157 as indicated in Figure I. Prototype fills have a 6 m deep cone plug of 16:1 T:C which is accounted for in the comparison of centrifuge model test with analytical results."

Jan 1, 1989

By Neillm Alastair S.

"This paper looks at what has happened in the past decade in the rare earth industry, particularly for those companies outside China trying to develop alternative projects to the Chinese dominated supply chain. The rare earth industry has gone through a metamorphosis over the past decade. The industry was basically unknown outside China until overnight it became the next hot topic on the financial streets of Canada and Australia. Suddenly various junior miners shifted from uranium and other out-of-favor commodities to rare earths as funds were easy to access from an investment community that did not understand the complexities of the space. The initial funding was done on traditional junior mining metrics of grade and deposit size. This has morphed over time to:1) Lights versus heavies2) Making a concentrate3) The importance of separation4) Off-take agreementsAt the peak of the market frenzy certain flagship operations were built using the “Not Made in China” moniker. Unfortunately certain errors were made during implementation, which are finally coming to the surface and making the rest of the pack wondering what will happen next. A review and update of some of the mistakes made and lessons learned will be discussed.BACKGROUNDAbout ten years ago awareness started to form around the rare earth industry and various groups recognized that because of the closure of Molycorp, Mountain Pass, and the dominance of China, there was a risk of uncertainty of reliable supply. This was not news for those active in the industry like Rhodia (now Solvay), the Japanese, South Koreans and other key consumers but to others it was like a light went on and rare earths became the new “.com” trend for investment banks, investors and some mining companies looking for the next hot topic.In the late 1990’s Molycorp accounted for around 20-25% of the world’s supply of rare earths, mostly lights (La, Ce, Pr and Nd), with small amounts of heavies from other sources. Then environmental issues forced the closure of the operation at Mountain Pass. Within six months China had increased production to plug the gap in supply. Around that time China was developing a strategy to leverage their position in rare earths and implemented a series of regulations to increase the value added component of rare earths inside China."

Jan 1, 2016