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By G. Goodall, R. Jabbar, S. Muinonen, A. Cummings

"Glencore’s Sudbury Integrated Nickel Operations in Falconbridge, Ontario, has been in operation since 1930. Many new technologies and practices, now common in the industry, have been implemented at the site and contribute significantly to the industry’s understanding. Since the last update on the Smelter operation published at the NiCo 2005 conference, the Converter Aisle has undergone significant changes in the operation of vessels. The Aisle continues to consist of 4 Peirce-Smith converters, but the Slag-Make Converter, and the Slag Cleaning Vessel have been re-tooled or re-built as Hybrid Vessels (HV), each generating matte for the two Finishing Converters and clean slag for disposal. The complicated scheduling and the overall benefits to the Smelter are reviewed here as part of the on-going tradition of industry support.INTRODUCTION The Glencore Nickel Sudbury Smelter operates a Roast Reduction Smelting (RRS) flow sheet with a specialized Converter Aisle operation that maximizes metal recovery to Bessemer matte. The main process equipment consists of a pair of Fluid Bed Roasters, a submerged-arc Electric Furnace and four Peirce-Smith converting type vessels (Figure 1). In the RRS flow sheet, concentrate is roasted with air to remove sulphur as SO2. Calcine from the Roasters is mixed with petroleum coke upon addition to the six-in-line rectangular Electric Furnace. The coke back reduces the metallic oxides, producing a matte and a discard slag.Gases from the Roasters are sent to a single pass absorption Acid Plant where the SO2 is converted to acid. Under the previous operating targets, approximately 70–75% of the sulphur in the incoming concentrate was fixed as acid with the balance going to the Electric Furnace in calcine for Bessemer matte production. Off-gases from the Electric Furnace and Converters are combined in a balloon flue, treated for particulates in electrostatic precipitators and discharged to the Smelter stack without any SO2 fixation."

Jan 1, 2017

By X. L. Wang

Hydrothermal method was applied in the preparation of calcium sulfate whiskers in airtight re-actor using gypsum as primary materials. The optimum conditions of preparation are as follows: pH value 9.8~10.1, concentration 5%, material size 18.1µm, which were determined by the analysis of the diameter of CaSO4 whiskers through SEM. On these conditions a product of ultrafine CaSO4 whiskers with diameter of 0.19µm and aspect ratio of 98 is obtained. Ultrafine CaSO4 whiskers with different concentrations, modified by titanate NDZ-401, were added into polypropylene as intensifier and composites of Ultrafine CaSO4 whiskers/ polypropylene were prepared by melting-extruding method. Mechanical performance of the composites was tested and surface morphology of the composites was observed by SEM. The results indicated that impact notched izod of the composites was enhanced by 49.5% compared with pure polypropylene when 10.0% Ultrafine CaSO4 whiskers were added into polypropylene and toughening effect was very remarkable. Dispersion behaviour and interface phenomenon of Ultrafine CaSO4 whiskers in polypropylene matrix were investigated by SEM. The results indicated that Dispersion performance of Ultrafine CaSO4 whiskers modified by titanate NDZ-401 in polypropylene matrix is good, which improved mechanical performance of composites to some extent.

Jan 1, 2014

By Gus Van Weert

Hydrometallurgical oxidation of sulphides is capital and energy intensive, with autoclave and bio-technology competing for lowest overall cost status. The use of surface aerators instead of stirred tank reactors could provide lower costs for bio-oxidation of concentrates. With this in mind, the Delft Inclined Plate reactor was designed with inclined plates above a settler shaped reactor to continuously return slurry from the lowest point in the settler to the surface of the liquid. The multiplate superstructure overcomes the scale-up restriction of the standard circular surface aeration patterns. DIP aerator energy and volume requirements for oxygen transfer from air will be presented in terms of kg O2/kWh and kg O2/m3/h transferred as a function of wt % sand in the slurry and compared to stirred tank performance. Scale up from the 4 m3 pilot unit will be discussed.

Jan 1, 1996

By Rainer Antretter

"THE CHALLENGE The 14km long, Arlbergtunnel, closed for public traffic during summer 2015, receiving a comprehensive and substantial renovation from 2015 to 2017. The main works discussed here, carried out during 2015, comprise 37 drill and blast SEM/NATM emergency escape tunnels from road level to the ventilation duct plenum have to be constructed as well as eight additional lay-by niches and three transformer tunnels. This presentation comprises the construction ventilation design, designed according to national regulations, suitable for 150 employees working 24/7 simultaneously at more than 40 single working sites lined up along the tunnel. The ventilation-system chosen was utilising two existing shafts for intake/discharge and a cross passage to surface, to handle a total fan power of 1.600kW. DESCRIPTION OF RENOVATION WORKS Linking Tyrol and Vorarlberg, two Federal States of Austria, the Arlbergtunnel is a single tube two-way road tunnel with vent duct plenum, constructed in the mid-1970s. According to latest EU legislation, additional escape exits have become obligatory. The existing seven cross passage links to the adjacent Arlberg Railway Tunnel, with average spacing of about 1.500m constructed in 2007, an additional upgrade to shorter escape spaces of approx. 400m was now required to comply with the updated legislation. Additional transformer tunnels, lay-by niches and small niches for emergency maintenance use, cleaning and other purposes, as well as a the installation of a new fire main in the invert, coupled with the simultaneous replacement of virtually the entire power and signaling cables, generated several dozen small and large single sites distributed along the 14km of tunnel.Purpose of the 37 walkable emergency escape tunnels is to reach the “upper deck” of the Arlbergtunnel, the vent duct plenum. These have an 180deg curve in plan, inclined at 10% and approx. 60m (65yd) long tunnels, excavated using drill and blast method starting from road level and working upwards to the level of an “intermediate soffit”, the vent duct plenum in the crown of the tunnel. The vent duct plenum is separated into a fresh air part and an exhaust air part, shown in Figure 1. The escape tunnels end with a pressure door in the fresh air section of the ventilation duct plenum. From there illuminated signs show the shortest escape route to the safe area between the road tunnel and the railway tunnel, as shown in Figure 2."

Jan 1, 2016

By Lizelle Glaner

An investigation was carried out by Mintek to investigate the influence of additions of gold to ?Fecraloy?, alloys based on Fe-Cr-Al. The aim was to try and improve the oxidation resistance of the ?Fecraloy? alloys at elevated temperatures over extended periods of time. The ?Fecraloy? alloys are very oxidation resistant alloys already employed in industry as substrates for metallic catalysts in auto-catalyst systems for high performance cars. Since their life and durability is limited by the slow, but steady, oxidation of the substrates, any change in the growth or stability of the oxides could be an improvement.

Oct 1, 2003

By R. Havens, B. K. Shilber

"INTRODUCTION In the course of the investigation of the occurrence of manganese deposits in the western United States, ore-dressing tests were made on three samples procured by Bureau of Mines engineers from two properties in southeastern Juah County, Utah, each of which is known by the name Black Jack. To avoid confusion, the tests will be described under the names of the owners Kendall-Duvall and the Empire Mines.None of the samples were amenable to ore dressing for the production of high-grade manganese sinter.Ores from the Kendall-Duvall deposit represent an interesting metallurgical phase of low-grade manganese occurrence, as the occurrence of manganese as silicate (braunite) automatically governs the extent to which they can be beneficiated by mechanical methods of treatment. As less than 50 percent of the total manganese was recoverable by complex methods of treatment in a 40- percent-manganese sinter, attempts were made to recover most of the manganese in a low-calcite, intermediate-grade product that might be acceptable for subsequent metallurgical treatment. By selective flotation of calcite and manganese, up to 68 percent recoveries were obtained in plus 20-percent manganese products..No encouragement can be given for successful ore-dressing of Empire ores as represented by samples received for testing, as no products were obtained that would meet minimum marketing specifications. Empire ore contained only 1 percent lime and might be high enough in grade (19 percent manganese) for direct hydrometallurgical treatment."

Nov 1, 1947

By David A. Orava, Richard C. Swider

"The technical knowledge and practical experience accumulated by industry and others in abating acid mine drainage (AMD) is being proactively applied at every phase of the mine life cycle. This paper traces the mine life cycle from exploration to post closure monitoring and maintenance, and reviews AMD abatement measures that have become an integral component of exploration and mining activities.Attention is increasingly being given to evaluating AMD potential as part of exploration work, and studies related to project feasibility and design. Mining, mineral processing, and waste management options are selected taking into consideration their suitability to inhibit AMD. These inhibition measures are typically committed to in closure plans submit-ted at the permitting stage. Mines are operated and decommissioned, often progressively, as planned and in accordance with environ-mental protection policies."

Jan 1, 1996

By E. T. W. Bailey

A HISTOR Y of the development and application of instruments, from the simplest U gauge to a modern indicating recording controller, would contain many interesting accounts of difficulties experienced and over-come. Important as is the history of development to any branch of science, this phase will, of necessity, have to be omitted from this paper and remarks confined to the results from the use of instruments in their present form. The steel industry bas, in the past decade, become increasingly instrument minded. More than ever, economy and adherence to doser specifications are demanded, and any tool that will aid in attaining these objectives by intelligent application and use finds a ready acceptance. The open-hearth furnace bas offered a field for instruments which is different from almost any other and one in which even a small percentage saved in operating costs may represent a considerable sum. Nevertheless, this department of the steel industry has been more cautions than most others in accepting the benefits which automatic control bas given on many other types of industrial furnaces, and one is puzzled why open hearths have not more generally benefited by the application of controlling instruments. The furnace operator bas to adjust the same three main valves that control fuel, combustion air, and stack draft as on most other furnaces, with the additional regulation of reversing the furnace. He is just as aware of the importance of proper draft control and correct air volume to burn most economically the applied fuel as any good boiler-plant engineer. What, then, are the special conditions that pertain to the open-hearth furnace?

Jan 1, 1939

By A. G. Starliper

Laboratory studies were made to produce whiskers of tungsten over a wide range of operating temperatures. Hydrogen reduction of tungsten hexachloride in a vacuum furnace at temperatures from 2,7000 to 3,3000 C yielded a small quantity of tungsten whiskers, provided a low degree of supersaturation was maintained. Direct measurements of 3,000,000 to 4,000,000 psi were obtained for the ultimate tensile strengths of individual whiskers averaging 3 to 4 microns in diameter with average aspect ratios of 1,000. This compares with strengths of 300,000 to 400,000 psi for 13-micron-diameter commercial filaments.

Jan 1, 1968

By Jerzy A. Mielczarski

The separation of albites from quartz by flotation applying the conventional HF-methods is no longer acceptable from an environmental and health point of view. Therefore, the search for a new reagent scheme without using HF depressor for separation of albite from quartz is under consideration. The flotation behaviour of ore mineral components depends on the produced hydrophobic or hydrophilic surface coverage (chemical functionalization). Currently we have excellent possibility of monitoring surface composition and structure at molecular and atomic levels at surfaces of natural minerals contacted with aqueous solutions of collectors, activators, depressants which is vitally important for the understanding of the surface chemistry that govern selective and efficient flotation. Detailed surface characterization of minerals before and after their exposition to different solution conditions was performed by the most modern spectroscopic techniques such as developed by us the infrared external reflection technique combined with spectral simulation and X-ray photoelectron spectroscopy (XPS). It is possible to monitor surface reactions which facilitate the separation process and those which bring disadvantage to selective flotation. At first we found that a small amount of ?mineral impurity? presented in natural ore could play important role in selective hydrophobization process. It was found that the pH of solution (parameter possible to control) and natural mineral impurities present in mineral samples (parameter related to ore origin) play a very important role in the separation process. Another important parameter is interaction between minerals, quartz and albite, present in aqueous solution. The limitation of flotation separation resulting from chemistry will be discussed. Moreover, the most promising scheme for separation of albites from quartz will be examined.

Jan 1, 2014

By D. Emadi

The ASTM B108 Mould and a Modified Mould were used to cast test bars under a variety of conditions: mould and pouring temperatures, mould coating and tilt. Mechanical properties were determined in the as-cast and heat-treated conditions. The ASTM Mould is less sensitive to casting variables. Enlarging the gating system and adding additional gates to the ASTM mould can improve properties in the tilt position. The reproducibility of properties in as-cast and T6 heat treated bars was investigated.

Jan 1, 2004

By Ralf M. Kleine

THE property of Consolidated 1 Discovery Yellowknife Mines Limited, (Figure I) is situated in the Northwest Territories, approximately 50 air miles north of the town of Yellowknife. The mine is reached by a shaft which extends from surface to a depth of 4,000 feet, with working levels established at 1 50-foot intervals. Stopping operations are carried on throughout a vertical range of 2,000 feet, with both shrinkage and cut and fill methods being used, depending on the ground conditions. Production started in 1950 and milling is done in a 1 65-ton per day cyanide plant. During ten months of the year, the property is serviced entirely by air, utilizing charter aircraft from Yellowknife. A 4,000-foot runway near the mine was constructed from mill tailings. This strip is adequate to receive Bristol freighter planes carrying heavy loads. Other servicing is done by Otter aircraft, equipped with skis or wheels for winter and with pontoons for summer operations.

Jan 1, 1962

By F. Calizaya

A booster fan is an underground ventilation device installed in the main airstream to handle the total quantity of air circulated to one or more working districts. It is installed in a permanent stopping and equipped with airlock doors, a monitoring system and interlocking devices between the main fan and the booster fan. When adequately installed, a booster fan can be used to reduce the main fan pressure, reduce leakage and decrease the power consumption. However, an inadequate installation can increase the likelihood of mine fies and recirculation of air contaminants. This study identifies hazards associated with the operation and maintenance of booster fans. It analyzes the accompanying risks and recommends control measures to reduce those risks to acceptable levels. The ventilation network of an existing coal mine was updated to include a booster fan. The hazards associated with the operation of this fan were identified, the risks analyzed and the esponse to each failure mode established.

Mar 1, 2014

By E. Gaucher, M. St-Amant

"Among the electromagnetic surveys performed by SOQUEM in the last three years, a certain number of the more instructive cases have been chosen to illustrate the theory of electromagnetism by field examples of: (a) The depth penetration of the TURAM as compared to the SLINGRAM (Ronka) method. (b) The limitations of the TURAM as compared to the SLINGRAM method when a conductor dips the wrong way, or when it is small in size. (c) The expression of a shallow-dipping conductor in a SLINGRAM survey. (d) The effect on the SLINGRAM survey of deep ditches or reef structures.(e) A comparison between the CRONE and the SLING-RAM method in the Abitibi clay belt, by means of field and model studies, indicating a usually better signal-to-noise ratio for the SLINGRAM method. From the above and from other experiments, different electromagnetic methods are now being used by SOQUEM, depending on field conditions."

Jan 1, 1970

By Thomas Mütze, Petya Atanasova, Kai Bachmann, Urs A. Peuker, Thomas Leißner

"A method is presented for the evaluation of mineral processing by liberation and upgrading. The method bases on the plot of recovery of valuables versus the recovery of gangue (Fuerstenau upgrading curve). The locking curve of a feed material was plotted together with the upgrading curve in a Fuerstenau diagram. The assessment of liberation and upgrading is done by a comparison of surfaces formed by the curves and some characteristic lines of the diagram. This plot allows the calculation of two new quantitative measures for liberation and upgrading. Both parameters can be combined to a third parameter describing the quality of the whole technical setup for mineral processing by subtracting the upgrading parameter from the liberation parameter. The third parameter shows a positive value in cases of upgrading determined processes, a negative value in cases of liberation affected processes and about zero for processes affected equally by liberation and upgrading. Thus it is easily possible to distinguish between poor results in the mineral processing caused by insufficient liberation or poor results caused by insufficient upgrading. Preliminary results from two case studies, performed on two different ore types, are very promising illustrating the practical use of such an approach."

Jan 1, 2014

By A C. Robertson

World urban expansion puts constraints on the available land surface area of our major cities both for accommodating people as well as providing infrastructure and services whilst at the same time attempting to preserve the remaining natural environment. Whilst consideration is often given to underground planning for private and public transport infrastructure, the author is of the opinion that the current lack of underground planning of our cities that are suitable for underground development will have major long implications when finally the need for underground space planning is critical and ultimately recognised. This paper identifies the need for our city planners to integrate surface planning and underground planning as a ‘total planning solution’ where the city plan incorporates the elements of underground space planning as identified in this paper. Investigations by the author reveal that there are very few cities in the world that actually incorporate underground space planning in their city plans. The author uses the City of Brisbane as a case study for the potential introduction of underground space planning as part of the city plan. Despite efforts by the author to include the planning concept of underground commercial development in the latest Brisbane City Plan 2014 as well as four underground space workshops in Brisbane over the past 20 year through the Australasian Tunnelling Society (ATS), underground space planning for the City of Brisbane, apart from infrastructure projects, is not considered of significance to the City of Brisbane.CITATION:Robertson, A C, 2014. Commercial underground space – planned development for the future, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 513–518 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By G. Coryell, S. Blaskovich

"A computer model has been developed to simulate the flash furnace and converter operations at the ASARCO Hayden Copper Smelter. The focus of the modeling was to optimize the converter operation to eliminate high matte level episodes in the flash furnace. These episodes (reducing feed to the furnace) resulted from the lack of converter operation scheduling. The model provided ""what if?"" scheduling scenarios that led to increased efficiency of the converter and flash furnace operations.This paper discusses alternatives studied to optimize the converter operation and the development of the computer modeling program, including implementation of the project. The discussion details the results of the project including the conversion from batch to a real time converter scheduling process. IntroductionASARCO's Hayden Smelter consists of a fluid bed drying system, an Inco oxygen flash smelting furnace, Peirce Smith converters, two anode furnaces and two casting wheels, gas cleaning plant, 2800 stpd sulfuric acid plant, 650 stpd oxygen plant and 200 gpm water treatment plant. The process flow sheet of the plant is shown in Figure 1.Over the past several years, the Hayden smelter has been involved in productivity improvement and cost reduction programs. This has been necessary to become a low cost copper producer in today's market. Part of the productivity improvement program was the use of process control to streamline the flash furnace and converter operations. Process control, through the use of computers and electronic controllers, has played an increasingly important role in optimizing processes in the Hayden Plant since the startup of the Inco flash furnace in 1983."

Jan 1, 1989

By K Timtner

As shown in former publications there are problems in load sharing of backstops in multiple drives of conveyors. Therefore, detailed calculation methods and design recommendations are required. In this paper various designs of load sharing methods are described and a dynamic torque calculation method will be presented. With this method the loadsharing properties for low and high speed backstops are calculated and compared. These properties depend on the spring characteristic of the drive train between backstop and load. Furthermore, the properties depend on the method of torquearm support and shock absorber configuration. Remarkable differences for external and internal backstops are shown

Jan 1, 1998

By John H. Low

Introduction Despite the fact that the .association of magnetite with chrysotile asbestos in the parent producing area of the world, the Thetford Mines - Black Lake area, has been recognized since the ores of that region were first known, magnetic methods were not extensively employed in exploration for asbestos until about the beginning of 1949. Since then, large areas of Ontario, Quebec, and the eastern United States have been prospected both by aeromagnetic and conventional ground magnetic methods. Prior to 1949, a limited amount of magnetic work had been done, notably that of A.H. Miller (1, pp. 184-186), which was carried out in conjunction with the geological survey of the Thetford area by H. C. Cooke (2) in the years of 1930 to 1932. At that time, Miller pointed out that the occurrence of asbestos is associated with very large magnetic 'anomalies' and that, within the Pennington dyke, an area of asbestos- bearing peridotite could be distinguished, by the anomalies, from adjacent areas of non-asbestos ?-bearing peridotite. Since he .also observed large anomalies in what were believed to be ?barren areas, Miller concluded, however, that the magnetometer could hardly be of much or any value in the direct location of asbestos War .and post-war demands on known reserves of asbestos ore, however, stimulated the search for new deposits, and an economical and rapid method of directing speculative drilling was most desirable.

Jan 1, 1951

By D. R. Parker

"This paper canvasses emerging trends in public policy and law, which may influence the zinc industry's interest in recycling. There are forces at work beyond direct economic benefits that will drive recycling of zinc, including:• corporate determination to pursue sustainable practices and product stewardship.• public perceptions and pressure,• customer and investor demand,• workforce recruitment, and• protection and expansion of marketsIn this paper, these ""indirect"" forces are examined with particular focus on the zinc industry: It is concluded that, in today's world with an emerging precautionary approach to policy and law making, public perception concerning the environmental implications of metal products, and the need to conserve resources for future generation, a strong industry response is required."

Jan 1, 2000