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By C. Barnett

"The mill at Noranda Mines Limited, Geco Division in Manitouwadge, Ontario went into production in 1957 treating 3,500 tons per day of copper, zinc, silver, lead ore. It was not until 1964, however, that the zinc concentrate drying plant was constructed. In 1970, milling capacity was increased from 4,000 to 5,000 tons per day. The zinc content of the ore is quite variable so that the tonnage of zinc concentrate dried varies from 200 to 650 tons per day.The drying plant was designed to dry 25 tons of zinc concentrate, dry basis, per hour from an initial moisture of 8.5% to a final moisture of 2%. Major components were selected so that capacity could be increased to 35 tons per hour with minor modifications.The rotary dryer is a Hardinge type ""XH-12"" with a diameter of 80"" and a length of 50 feet. The all welded construction shell is 1/2 inch thick mild steel plate with 3/4"" thick reinforcing bands under the tires arranged for operation at a slope of 1/2 inch to the foot. The 3/8"" x 12"" radial flights are welded to the shell. There are no flights in the last ten feet of the shell in order to reduce dusting. This unit is driven by a 50 HP motor through a Hamilton type CD250 double reduction helical gear speed reducer. The shell speed is 5.8 RPM.The standard Peabody horizontal air heater has a rated capacity of 10,000,000 B.T.U. 's/Hr. The combustion chamber is lined with high temperature refractory brick and is air cooled. The conical outlet section of the air heater is lined with insulating fire-brick. The burner is a type AT wide range mechanical atomizer fired by a type ""CR"" gas-electric ignitor.The Bunker ""C"" fuel is supplied by a Compower duplex pumping, heating and straining unit, including tank hotwell, Powertronic oil line heating system with a 550/24 volt transformer."

Jan 1, 1972

By K. Blower

"Since there was no representative from Wesfrob Mines Limited, the information on their infra-red concentrate drying operation, which had been prepared by Mr. K. Blower, was presented by Mr, Dorland. Mr. Blower, in submitting the information, emphasized that their objectives in this operation were (a) to guarantee less than 90%, of flow-moisture in their copper concentrates and thus satisfy marine shipping regulation• and (b) to minimize capital costs, The infra-red dryers have satisfied these objectives.To control final moisture in the copper concentrate, current practice is to preheat the filter cake with steam in the disc filter hood and then conveyor-0r7 the concentrate with infra-red calrod heaters. The application of steam aids the system as follows:1) Improves vacuum pump efficiency.2) Lowers viscosity of filtrate (increased temperature},3) Preheats the cake prior to radiant heating. (150°F)The hot cake discharging from the filter ranges from 10.6 to 10.9% moisture. After radiant heating the moisture level is reduced to 8.5% - 9.7% depending on production rate. Further moisture loss occurs during conveying and transferring to the stockpile for a final shipment moisture ranging from 8.1% to 9.5%. Production rate is frail J to 5 dry short tons per hour.1) #23 Conveyor 18"" flat belt covered from filter discharge to transfer point with 7 heaters end-to-end. Drive - Reeves Vari-Speed, 31:4 ratio, type 332-10-18, class ""D"", driving through a 24:1 ratio Dodge reducer. Speed of Conveyor - 3,9 feet per minute to 19.6 feet per minute. (Speed has been established and is not changed as a rule from the present level of a1:out 15.)2) #23 Conveyor 24"" wide, 20° troughed belt covered with 21 heaters, end-to-end from loading point, Speed - Constant at 54,2 feet per minute."

Jan 1, 1972

By H. P. Whaley

This paper introduces Wabush Mines, including its ownership, physical assets, capacity, goals and achievements. It is to be followed by four papers which will present the detailed story. Wabush Mines, the largest supplier of iron ore to the Canadian steel industry, was brought into production in 1965. The ore is mined and concentrated in Wabush, Labrador, Newfoundland and pelletized at Pte. Noire, Quebec. Annual capacity is over 6,000,000 tons of high-grade iron ore pellets.

Jan 1, 1969

By Kish. L.

"The results of a chemical and mineralogical study of eighteen opaque-oxide occurrences are discussed and the detailed chemical, metallurgical and mining feasibility study of a vanadium-rich magnetite deposit is summarized. A plot of the mol-percentages in the system FeO- Fe2O 3-TiO2 indicates that the deposits fall into two distinct groups: some contain hematite with ilmenite, and some others have magnetite with ilmenite (titaniferous magnetites). The plot also suggests that the two types of deposits were crystallized from liquids of different compositions. Each group has its distinct structural features. Vanadium is present in all of the studied specimens, however concentrations of economic importance have so far been found only in the titaniferous magnetite deposits. The vanadium content of the oxide concentrations of the Dore Lake Complex is the largest among the studied occurrences. Analyses of the concentrates of the drill-core sections show a compositional variation across the orebody; a continuous increase in the tenor of Ti02 and a decrease in the vanadium content upward in the layered sequence is found. Concentration tests on several tons of samples indicate that about 80 per cent of the vanadium is recovered in the magnetite concentrate."

Jan 1, 1972

By S. W. Henley

"Shaft sinking design is typically driven by what has been successful in the past and the availability of sinking plant. This document considers a project where the sinking design and methodology is unconstrained by conventional thinking and removed from the commonly held belief that a sinking methodology should be developed from available winding plant. Schedule was a key driver for the Project and led to an alternative sinking design that aimed to optimise sinking advance rates by specifying new winders that compliment known sinking plant while providing improved safety, redundancy and flexibility within each part of the sinking cycle. KEYWORDS Consistent, Efficient, Flexible, Improved, Innovative, Optimise, Redundancy, Safety, Schedule INTRODUCTION The project is remotely located in the South Gobi region of Mongolia on a brownfield site and the scope of work included the concurrent blind sinking and concrete lining of two (2) ventilation shafts to an approximate depth of 1,150 m at a finished diameter of 10 m and 11 m respectively. All sinking and lining operations to be completed as in-line activities, (no lining whilst other activities are undertaken). The project was schedule driven with a completion date set for the first quarter (calendar) of 2021 and there were no restrictions imposed on the successful Contractor with respect to their equipment selection. Existing sinking plant already onsite from three previous shaft sinking operations would be made available to the Contractor if required on an as is where is basis Sustained advance rates in excess of 2.4 m per day would be required in order to achieve the completion milestone, therefore the design would have to include contingency and demanded flexibility to account for equipment down time. Previous shafts that had been sunk onsite have utilised a single double drum kibble (bucket) winder (hoist) with a single excavator loading on the shaft floor into a large capacity kibble (bucket). DESIGN Mucking The sinking design centred on the mucking cycle given that this is traditionally the most restrictive part of the sinking cycle and typically accounts for one third of the overall sinking cycle. The Vertical Shaft Mucker (VSM) and/or diesel excavator are commonly used plant for shaft sinking that were under consideration. The use of Cactus Grabs was not considered given the higher risk associated with grab ropes and hoist failures."

Jan 1, 2019

By L. Iacopetti, A. Calderara, M. Perego, P. Perrone, T. Furusawa

De Nora, a global leader in the development, manufacture and sale of all DSA® anodes based on titanium coated with mixed metal oxide (MMO) for electrochemical processes will present key advancements made to Self-Protected Anodes (SPA) for metal electrowinning. (DSA® is a registered trademark of Industrie De Nora S.p.A., Italy). In 2017 pre-commercial demonstration cells were operated in industrial environment. The program’s focus was to fully demonstrate the SPA anode’s superior mechanical and electrochemical robustness during normal and induced dendrite shorting occurrences while providing quality of plating in commercial operation. De Nora specialists focus on key components, in particular the engineering of the self-protection system, DSA® anodes and catalyst formulation capable to cope with high levels of pollutants while providing long service life in the meantime. Results of field trials confirmed the expected anode performance and enabled the selection of the most suitable “SPA” structure, based on resistive protective elements. Summarizing the economic benefits to copper electrowinning tankhouse operation with De Nora’s self- protected all DSA® anodes are; Double-digits power savings Cobalt-free electrolyte operations Minimal dendrite shorting damage incurred at the SPA anode Smoother, uniform cathode deposits with tangible improvement on current efficiency Tankhouse operations producing lead-free copper quality cathodes, in addition to elimination of lead waste for improved operator health and environment. INTRODUCTION De Nora’s engineered “Value Technology Package” (“VTP”) for electrowinning, consisting of our DSA® anodes coated with mixed metal oxide specifically formulated for copper electrowinning in conjunction with an advanced self-protected full titanium anode (“SPA”), underwent an intense field qualification program, inclusive of the behavior under massive short-circuits as part of the field investigation, with the goal to select and appoint the ultimate design configuration of “SPA”. Optimized wireless-based monitoring system was included in the field program, demonstrating good functionality for cell parameters monitoring and remote shorts detection.

Jan 1, 2019

By K. D. Bulin

"An interesting brief history review of shovels as the primary excavating tool will permit the reader to see that immeasurable development and resources have preceded the shovel excavators which today are used extensively throughout the mining industry. With this as a background, the shovel manufacturer has the ability to utilize his resources best in those areas of shovel development in which the maximum benefits of increased reliability, performance and ease of maintenance will improve the operating rewards to the user of the equipment. The author explains the function of the shovel as a part of the material handling system. A detailed description of those areas of the shovel in which the most recent developments and major improvements have been implemented in the manufacture of the shovel excavator arc included."

Jan 1, 1973

By E. Barnard, J. Tero, J. Rajala, N. Avenido, M. Fullam, A. Nashitati, S. Mbalamba

"The Otjikoto mining and milling complex is 90% owned by B2Gold Corporation, and began commercial operation on February 28, 2015. The milling circuit operates at a throughput 3.3 million tonnes per annum, with an average reserve gold grade of 1.28 g/t. The ore is high in Gravity Recoverable Gold (GRG), which varies between 73-91%, depending on ore type. Overall gold recovery since start-up is 98.2%, with about 63.5 % coming from the gravity circuit as doré. 2016 cash operating costs, and all in sustaining cost (“AISC”) were $361 and $604 per ounce, respectively.During design, three ore types were tested for GRG content, and based on the high GRG value of all three ore types, the decision was made to treat the full ball mill circulating load by gravity. Once operating, the gravity circuit performance was characterized by performing a detailed gravity audit, which included the ore, cyclone classification, Knelson concentrators, and the Consep Acacia intensive leach system. The deeper ores contain significant pyrrhotite, and this created some unusual challenges that had to be overcome. This paper presents the gravity circuit design process, the circuit commissioning, and the audit results and ongoing improvements.IntroductionHeadquartered in Vancouver, Canada, B2Gold Corp. was founded in 2007. Currently, B2Gold has five operating mines, and numerous exploration projects in various countries, including Nicaragua, the Philippines, Namibia, Mali and Burkina Faso. The Otjikoto Mine is located in the north-central part of the Republic of Namibia. It is situated approximately 300 kilometers north of Windhoek, the country’s capital, within the Province of Otjozondjupa. The Otjikoto mining and milling complex is 90% owned by B2Gold Corporation, and began commercial operation on February 28, 2015. The milling circuit operates at a throughput 3.3 million tonnes per annum. During design, a large emphasis was placed on gravity recovery, as the Otjikoto ores are unusually high in Gravity Recoverable Gold (GRG)."

Jan 1, 2018

By M. Harrison, C. H. Stockwell

"Metals vah1ed at more than $200,000,000 have been obtained, mainly since 1930, from the mines of northern Manitoba. The greater part of this production has been copper, zinc, and gold from the Flin Flon, Sherritt Gordon, and Mandy mines. The chief mines from which gold alone has been produced are God's Lake, Laguna, and Gurney. At present (May 1947) Flin Flon and Sherritt Gordon are the only producing mines, but the Nor-Acme property is being developed for large-scale production of gold. Large deposits of nickel and copper are being diamond drilled at Lynn Lake, and the Thompson, Ferro, and other properties are being developed. The mineral deposits lie within irregular or elongated areas of Precambrian sedimentary and volcanic rocks, surrounded by granite ( Fig. 1).The common rock types include basic and acidic flows, agglomerate, ruff, greywacke, arkose, argilli te, conglomerate, and their gneissoid and schistose derivatives. They are invaded by sills, dykes, and irregular bodies of gabbro and diorite, and all are cut by granite. Some of the sediments are interstratified with volcanics, and others are deposited unconformably on them.STRUCTURAL GEOLOGYLittle is known of the structures of the rocks in the area as a whole, because by far the greater part is unexplored or has been covered only by reconnaissance surveys. Available information indicates a general east structural trend in the southeast part, whereas in the west part the folding is mote complex with no definite overall trend. However, in a few small areas in the western part where detailed work has been done, as around the Flin Flon, Sherritt-Gordon, Nor-Acme, and other properties, the structure is fairly well known. The following descriptions apply chiefly to these areas ."

Jan 1, 1954

By T. Xu

"The CTL-500 centrifugal extraction machine, which was independently developed by Baotou Shibo Rare Earth Extraction & Equipment Co., Ltd., is presented in this article. The machine is based on centrifugal extraction principle and has been used in P507-HCl-RECl3 extraction system. Automatic control has been utilized in the system. In this paper, a comparison is made between centrifugal extraction and conventional mixer-settler extraction and satisfactory results are shown. INTRODUCTIONCentrifugal extraction is a fast and efficient liquid-liquid extraction method. The process includes solute transfer and separation of the two liquid phases. In the CTL-500 machine, the organic and aqueous phases individually enter a lower mixing chamber in certain proportions and are mixed and dispersed and solute thereby transferred from one phase to the other. The mixed phases pass into a rotating drum and the two liquid phases are separated under centrifugal force. As it flows upward, the aqueous phase, which has a higher specific gravity, flows away from the rotating drum centre towards the drum wall and the organic phase flows towards the drum center. The two liquid phases enter into collection chambers through independent weir plates and are discharged from the machine.The centrifugal extraction machine has been widely used in liquid-liquid separation, either without solid or with small quantities of solids (Chen, Zhang, Zhuo, Chen & Li, 2008; Duan, Jing, Zhu & Chen, 2007; Duan, Zhou & Zhou, 2006). Examples of the use of the centrifugal contactor include the separation of water from crude oil, treatment of heavy oil and diesel to eliminate water and salt; the extraction of penicillin, garlic oil, malathion, and interferon; the hydrometallurgy recovery of nickel, copper and uranium; extraction of edible oil, spice, refined oil and food color; treatment and recycle of print and dyeing wastes; treatment of hydroxybenzene-contaminated sewage by multistage extraction and separation of water from oil in ship sewage."

Jan 1, 2012

By B. K. Gorain

Barrick' s Buzwagi copper-gold deposit in Tanzania comprises oxide, saprock and sulphide mineralized zones averaging approximately 0.058oz/t gold, 0.13% total copper and 0.03% cyanide-soluble copper. A comparative evaluation of the project based on two potential flowsheet alternatives is presented. The first flowsheet included a gravityconcentration and carbon-in-leach (CIL) plant. The second flowsheet was based on a Gravity-Flotation-CIL plant, which proved to be more economically robust. Selective flotation of copper minerals to produce a saleable copper concentrate proved to be challenging. Detailed characterization of the Buzwagi deposit was carried out through understanding of ore mineralogy, mineral liberation, floatability and selectivity, reagent chemistry and regrinding issues. With this insight, a flotation concentrate of greater than 25% Cu was achieved, recovering a significant amount of copper minerals and tellurides. The overall economics of the project improved significantly with the addition of flotation. Leach tests on gravity and flotation tailings showed an overall increase in gold recovery of approximately 6% for a Gravity-Flotation-CIL plant compared to that for a Gravity-CIL plant.

Jan 1, 2007

By B. Ignasiak

Laboratory studies suggest that improvements of coke strength brought about by pre-heating caking coals before carbonization accrue from inadvertent oxidation rather than from other low-temperature changes in the coal mass. Controlled oxidation of highly caking coal, followed by laboratory carbonization, produces cokes which, in terms of a laboratory scale tumble test index, are equivalent to those obtained from prime metallurgical blends. Appropriately formulated blends of exhaustively oxidized and fresh caking coal similarly yield cokes with strength indices comparable to those of cokes made from the same coal after oxidation under optimum conditions.

Jan 1, 1979

By R. Rumpold, J. Antrekowitsch

"The continued increase of the automobile production leads to a higher platinum, palladium and rhodium (PGM) demand. Due to the high value of the PGMs the recycle of these metals from automotive catalysts is of special interest. Pyrometallurgical processes, which are only focused on the PGMs, represent the state of the art of automotive catalysts recovery. However, hydrometallurgical recycling processes offer additional recovery of other valuable metals and compounds. The method presented in this paper is based on a combination of hydrochloric acid and hydrogen peroxide to dissolve the valuable metal fraction which can be precipitated afterwards.INTRODUCTIONPlatinum and the corresponding metals from the PGM group, especially palladium and rhodium are well known as catalytic active materials. They support chemical reactions which are inhibited. This effect is used to decrease the amount of harmful compounds like hydrocarbons, carbon monoxide or nitrogen oxides in automotive exhaust gases. The generation of these toxic substances is based on incomplete combustion, which in turn is caused by non-ideal conditions in the combustion chamber. Catalytic converters minimize the harmful compounds by supporting the following Reactions 1 – 3 (Votsmeier et al., 2009).CO + ½ O2 ? CO2 (1)CnHm + (n + ¼ m) O2 ? n CO2 + ½ m H2O (2)2 NO + 2 CO ? N2 + 2 CO2 (3)Platinum and palladium are very effective for the oxidation (Reactions 1 and 2), while rhodium supports the decomposition of nitrogen oxides by carbon monoxide (Votsmeier et al., 2009). The classical three way catalyst was a platinum – rhodium combination with a Pt:Rh ratio of 5:1 (Hagelüken et al., 2005). Today the platinum, palladium and rhodium ratio is highly variable and strongly depends on the engine type as well as on the car producer. Diesel engines are operated with a super stoichiometric air addition in comparison to spark ignition systems. Therefore the exhaust gas composition and off gas temperature is different. Based on the high oxygen amount, diesel engines produce less carbon monoxide and hydrocarbons but more nitrogen oxide in contrast to gasoline engines. This leads to various requirements for the catalytic converters."

Jan 1, 2012

By Matthew R. Ward

This paper aims to describe the reasons and methods to extend enterprise networks into underground mines. Currently mines use a number of communication networks for telephones, PLCs, two-way VHF radio and computer networking. Each system can have different wiring, protocols, converters and interfaces all which require expansion and maintenance. The convergence of voice, video and data using Ethernet and TCP/IP has the very real benefit of one ?wire? for underground networks. Now that the majority of underground equipment can communicate using TCP/IP, network convergence can offer reduced network expansion and maintenance costs. Cost savings are good, but the truly exciting aspect of network convergence using Ethernet is the low-cost, high speed wireless networking now available . These wireless networks offer an opportunity to facilitate mining automation even on a small budget. How would mine operators change they way they operate if they could gather vehicle location and data in real time? What about controlling equipment remotely? The list of applications is long and includes traffic control, dispatching, real-time ore blending, tele-operation, automated production reporting, vehicle health monitoring, elimination of paper forms and immediate network access for surveyors and geologists. An ideal converged network for underground mining would be robust, inexpensive, easy to expand, enable fast and secure connections while keeping voice communication performance equivalent or better than what is now provided by VHF radio

Apr 1, 2005

By C. E. Dowker

"IntroductionMechanization underground at the Buffalo Ankerite mine in Deloro township, Porcupine district, had reached a high level by 1944, both in equipment available, and in the use of this equipment, for all stoping operations. Power feed leyners and the latest type of stopers for drilling, slushers for moving ore and fill, and tugger hoists for all servicing, did much to halt rising stope costs, and in some cases decreased them. On the other hand, little beyond the use of mucking machines and power feed leyners had been adopted in the effort to reduce level development costs, or to increase the advance per man-shift.Faced with ever increasing level development costs, caused by rising prices of equipment and supplies, coupled with increasing wage demands for less physical effort, it was realized that more mechanization of development work was essential. The objectives of such further mechanization were:(1) Decreased development costs(2) Increased footage per man-shift(3) Less physical effort by development crews, with greater take-home pay (4) A more satisfied and stable labour force"

Jan 1, 1950

By C. A. Anderson, C. A. Young, H-H. Huang, L. G. Twidwell

An equilibrium calculational computer program (STABCAL) can be used for titration simulation. The program can handle various forms of titrants: solid, aqueous, gaseous or another solution, and various type of reactions: reductive, oxidative and adsorption. Background chemistry, mathematical considerations, and program development will be illustrated. Also, simple titration applications such as how to determine the acidity of aqueous solutions and alkaline sulfide leaching of gold are presented. Processing of an acid mine water from the Berkeley Pit in Butte, Montana has been used for illustration purposes. The treatment studies included: cementation, sulfidization, and neutralization. The calculational results for the neutralization treatment using various alkaline reagents are compared to actual experimental data and potentially appropriate processes are discussed. Computational

Jan 1, 2005

By W. C. Whittaker

Introduction When one thinks of a coal stripping deposit, the picture that usually comes to mind is that of a more or less flat seam from two to twenty feet in thickness overlain by ten to fifty feet of overburden, in suitable ratio for economic operation. This is the usual type of stripping deposit and is quite a common occurrence in various parts of the prairie provinces. Rather unusual types of coal stripping deposits are being presently worked as open-cut mines by Sterling Collieries, Limited, and the Co al Valley Mining Company, Limited, at Miles 47 and 48 on the Alberta Coal Branch, some 150 miles south west of Edmonton. These deposits are of interest chiefly because they represent turned-up and greatly thickened sections of the Mynheer seam, and as such they present their own problems, peculiar to the commercial exploitation of a seam of this type. The area in which these deposits occur was originally owned by the Pacific Pass Collieries, whose operations, however, were confined to under-ground mining at Lovett, some eight miles to the southeast. It was not until l918 that the value of these deposits was realized, when the Company now known as Sterling Collieries, Limited, opened their pit at Mile 47. At the inception of the work, coal was loaded directly into the railway cars by men using wheelbarrows. In 1920, a tipple was built, after which the coal was loaded by steam shovel into mine cars, hauled by steam dinkeys, and loaded over the tipple into railway cars. In 1922, the Coal Valley Mining Company entered the field at Mile 48, with an entirely mechanical equipment, and at the present rime these two are the only stripping properties in Alberta using mechanical equipment both for the removal of overburden and the loading of the coal. These Companies have operated continuously since that time, and have to date mined and shipped 4,000,000 tons of coal, and moved some 5,255,000 cubic yards of stripping. The present annual coal output for the two mines is about 240,000 tons.

Jan 1, 1935

By G. Beckstead, L. F. Sawatsky, R. Nutbrown, D. Long, G. Gould

"This paper presents a case study for optimizing water management at Gregg River Coal Mine located near Hinton, Alberta. The optimization study was derived based on a review and assessment of existing management practices and plans for future operation and final reclamation. A proactive water management strategy was developed to assist mine staff in adopting a rational, environmentally sound, and economical approach to water management. A plan was developed to provide for safe operation, self-sustaining operation, low maintenance, minimum negative environmental impacts, and anticipation of future needs for existing and future operations. A plan for final reclamation drainage was developed including establishment of effective, sustainable, and maintenance-free water management systems. The study demonstrated the importance and benefits of a proactive approach for integrated mine water management. This approach is recommended for other similar mine operations because it will improve environmental compliance and reduce costs of water management. IntroductionGregg River Resources Ltd. (GRRL) operates an open pit coal mine on the eastern slopes of the Rocky Mountains, located about 45 km south of Hinton, Alberta. GRRL opened the mine in 1982 and expects to continue operations after Year 2000. GRRL has progressively reclaimed the disturbed area and expects to complete mine-land reclamation shortly after mining in the area is complete. The existing disturbed area and reclaimed area covers approximately 9.5 km2 and will expand to about 10.5 km2 upon mine closure.Like other coal mines in the mountainous areas of Alberta and British Columbia, the GRRL coal mine is subject to highly variable temperatures and moisture conditions. Average monthly precipitation varies from a low of 12.6 mm in January to a high of 113.0 mm in August, based on the precipitation record at the mine site since 1982. Despite the relatively high rainfall during the spring and summer months, excess water problems during rainfall events are quickly replaced by water deficit conditions during periodic droughts. Surface runoff varies from near zero in the winter to a mean annual monthly maximum of 78 mm during the month of June. The mean annual surface water yield is 345 mm."

Jan 1, 1997

By A. B. C. Stothart

"IntroductionIn the past four years Ontario Mines have made great progress in the development of reliable mine conveyance safety dogs. History shows that, prior to 1945, a rope failure on a descending conveyance was usually followed by unsatisfactory safety dog operation.It is proposed in this paper to discuss briefly;The history of this development. Progressive .development of one type (E. Long).Free fall testing of safety dogs. Anti-trailing rope device.HistoryOn February 2nd., 1945, a hoisting rope broke at the Paymaster mine. The safety dogs proved ineffective and permitted the cage to crash through to the bottom of the shaft, with disastrous results.Following this accident, the Ontario Government appointed a Technical Committee to investigate The Safety of Hoisting Equipment and Hoisting Practice in Ontario Mines. This Committee consisted of Dr. C. R. Young (Chairman) and Professors T. R. Loudon, E. A. Allcut, V. G. Smith, and Lloyd M. Pidgeon. The Ontario Mining Association (at the request of the Ontario Government) also appointed a Committee consisting of Messrs. R. E. Dye, R. D. Parker, and R. L. Healy."

Jan 1, 1950

By A. Warczok

Smelting slags contain payable metals in a dissolved form and as mechanically entrained matte or metallic inclusions in the size range from 2 to 1000 µm. Slag cleaning requires reduction of magnetite and metal oxides and sedimentation of inclusions. Slag cleaning in an electric furnace is carried out in batch or semi-continuous mode. The strong trend for continuous slag cleaning generates the basic question about the optimal geometry of the electric furnace. Results of combined CFD, potential distribution and heat transfer modeling allowed for the determination of the fluid flow pattern and the temperature distribution in a classical, circular electric furnace as well as in a rectangular furnace. For the rectangular furnace, various length/width ratios and position of electrodes have been simulated. Analysis of key phenomena pointed out the advantages of the rectangular electric furnace over the circular furnace, particularly for continuous slag cleaning. Phenomena that have been analyzed were mass transfer, the rate of slag reduction, coalescence and settling of inclusions, all on the basis of the calculated slag flow pattern and the temperature distribution.

Jan 1, 2007