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By D. A. Grieve

"Mineable coal seams in the East Kootenay region belong to the Mist Mountain Formation of the Jurassic -Cretaceous Kootenay Group. Three structurally separate coal fields (Crowsnest, Elk Valley and Flathead) are recognized, all of which are characterized by compressional tectonic features such as f aiding and thrust faulting, and by /ate-stage normal faulting. Tectonic history has greatly influenced coal mineability and quality. Coals range in rank from low to highvolatile bituminous, and reactive maceral content ranges from less than 60% to greater than 90%. A wide range of metallurgical and thermal coal qualities is found. Measured reserves (up to 1981) include 1.03 billion metric tonnes metallurgical and 165 million metric tonnes thermal coal. Introduction a) Location -Coal fields of the East Kootenays region occur in the Front Ranges of the Rocky Mountains, within 30 km of the Alberta -British Columbia boundary (Fig. 1). They extend over 175 km north from near the U.S. border, and occupy the regions of the Crowsnest Pass and Elk and Flathead River drainages. The deposits are accessible from Highway 3 (Fig. 1) and various secondary roads. The towns of Fernie, Sparwood, Elkford, Coleman and Blairmore serve the coal industry. East Kootenay coal deposits are contained in three structurally separate coal fields, the Crowsnest, Elk Valley, and Flathead coal fields (Fig. 1). Coal is currently being produced by B.C. Coal (now Westar Mining Ltd.) at Sparwood, by Fording Coal 20 km north of Elkford, by Crows Nest Resources at Line Creek 15 km southeast of Elkford, and by Byron Creek Collieries at Corbin. Westar Mining has also constructed a new mine on the Greenhills Range 8 km northeast of Elkford. Pre-requisite engineering and environmental studies have been carried out on the Elco Mining property, 35 km north of Elkford, and on the Sage Creek coal property near the U.S. border (Fig. 1). b) Coal land tenure -Coal rights in the East Kootenays are either held as freehold land, or are licensed from the provincial government. The former category includes lands acquired under the Railroad Act of 1890. Shortly after this the federal government also obtained 50,000 acres of coal-bearing lands from the Crown Provincial, the so-called Dominion Government Coal Blocks. Major holders of coal rights in the area are Westar Mining and Crows Nest Resources. Large blocks are also held by Fording Coal and related companies, Sage Creek Coal, and Canada Permanent Trust Company as trustee for Elco Mining, and small blocks are held by Byron Creek Collieries and Coleman Collieries. In addition the provincial government holds an area in reserve for possible future use of B.C. Hydro at the extreme north end of the Elk Valley coal field."

Jan 1, 1985

By Alfred L. Ransome

GOLD output in Alaska in 1950, following a 2-year decline, increased to the highest point since 1942. Tills unexpected gain in production of the Territory's greatest value commodity was largely responsible for the increase in the over-all value of mineral output in the Territory to $17,852,000 from $15,549,000 in 1949. Although coal continued to rank second to gold in value of output, production was slightly less than the record production of 1949. The mining of platinum continued to be an important factor in the mineral industry, with production of crude platinum metals exceeding that of 1949. The output of lead was three times the 1949 production, and silver gained 46 percent over the previous year's total. Copper and zinc production-entirely as byproducts from other ores-showed an increase, but remained minor. Production of tin was relatively small, but substantially above the total for 1949.

Jan 1, 1953

By T. J. Goff, G. M. Denton

Mintek has developed the EnviroplasTM process for the treatment of solid wastes from the metallurgical industry, especially steel plant dusts, without requiring agglomeration to produce inert slag and at the same time recover metal values such as nickel, chromium and zinc. The products that are generated in the plasma-arc process are usually a metal and a non-toxic slag, which are tapped from the furnace in liquid form. The metal is mainly composed of chromium, nickel and manganese. During the production of stainless steel between 30 and 70 kg of dust and fine waste is generated per ton of steel. Mintek has successfully processed around 1000t of AOD/EAF dust on a toll treatment basis in order to recover the contained Cr and Ni. The metal produced contained 18.5 per cent Cr, and 5.5 per cent Ni. All slag samples tested conformed to US EPA regulations for disposal. The chromium and nickel recovery to metal was 90 and 98 per cent respectively, on a once through basis i.e. no baghouse dust recycle. Slag tapping temperatures varied between 1650°C and 1750°C. The average actual energy requirement excluding furnace heatlosses of smelting steel plant dust with anthracite as reductant was 1.36MWh/ ton of dust. The total mass of feed reporting to the off-gas stream was 10 per cent. The average ZnO content of the fume was 35.5 per cent.

Jan 1, 2004

By H. S. Chiang, Y. Luo, S. S. Peng

"IntroductionThe way in which the particle sizes distribute in the airborne coal dust plays an important role in the transportation of the dust in the mine air and human respiratory systems. Though the particles of a size less than 10 microns could be inhaled, the real distractive portion of the dust is that the sizes range from 1 to 5 microns since only they can reach the lungs and be retained there. Those with an equivalent diameter larger than 5 microns will settle on the membranes of the branchial tubes(1) while those with diameter less than 1 micron can either be exhaled out of the lungs or the settled quantity is so insignificant that does very little harm to the lungs. In the transportation process, the finer dust will fly farther away from the sources than the coarser ones. Thus once the fine dust is generated and becomes airborne, it will spread out to a larger area.In this paper, the coal samples collected from two longwall faces were analyzed statistically for size distribu¬tion. A mathematical model is proposed and the effects of different conditions on the dust size distribution were analyzed using the mathematical model.Sampling and Statistical AnalysesSampling Instrument and ProcedureThe instrument used in the sampling were Mine Safety Appliance (MSA) personal sampling units equipped with 10-mm nylon cyclones, pre-weighed MSA PVC filters and constant-flow pumps.Two longwall operating faces were selected for the dust sampling. The two faces were located in two coal mines ex-tracting Pittsburgh seam. The double-ended ranging-drum shearer applying the unidirectional cutting sequence was employed. The two-leg shield supports were used for face support. The width of the two faces was about 215 meters.In each of the two faces, four sampling stations were set up. The stations were located at the cross-cut immediately outby the headentry side, the 15th support (25 m), 65th support (107 m) and 111th support (182 m) from headentry T-junction, and numbered as #1, #2, #3, and #4 station, respectively (Figure 1). At each sampling station, a group of three sampling units was hung at proper position. At cross¬cut (#1) station, the units were hung about one foot under the roofline in the center of the cut (Figure 2a), and at the stations in the face, the units were position near the hydraulic legs and one foot below the support canopy (Figure 2b).One complete set of 12 samples was collected for each day. The sampling were performed for five consecutive days. All the samplings were conducted in the morning shifts. The time duration of the sampling for each day was about five hours. During that time, the shearer might complete 5 to 7 mining cycles."

Mar 1, 1989

By Daniel T. Rogers

The Bureau of Mines, in its alumina miniplant project to investigate alumina recovery from domestic, non bauxitic ores, has conducted research on the use of a hydrochloric acid leaching, gas sparging crystallization technology. An important element of this research is the efficient separation of undissolved, siliceous residue from AICI3 -bearing leach liquors by continuous, horizontal, countercurrent vacuum belt filtration. In an effort to calculate material balances quickly and to predict material balances based on different belt filtration configurations, the perfect-mixing-cells-in-series model (PMCS) for calculating material balances around belt filters was used. Because of the porous nature of the solids, the model produced erroneous material balances. Therefore a reliable model, the shrinking voids model, was developed postulating the presence of an unwashable voids liquor volume that decreases with decreasing liquor AICI3 concentration. This volume decrease postulation is equivalent to assuming that dilute liquors flow more freely, causing more voids liquor volume to become washable. Least-squares based computer programs are provided, which are useful not only in producing material balances from plant data but also in predicting balances for untested configurations using the same feed materials.

Jan 1, 1982

By Philip C. Tully

The Bureau of Mines, in a continuing effort to improve processes and methods of helium purification, has developed a differential distillation method for removing helium-3 from helium-4. Differential distillation at 4.2 to 1.6 K was used to reduce the helium-3 in helium-4 from about 200 to less than 1 part per billion. The results from four stills ranging in size from 1 to 25 liters are reported. The method has the potential to be adapted to commercial-scale separations.

Jan 1, 1975

By P. Niessen, S. J. Bercovici

RECENTLY Aust et al.&apos; proposed a model of non-equilibrium grain boundary segregation based on a vacancy gradient induced uphill diffusion process of solute to grain boundaries. According to their proposal, solute atoms which are attracted to vacancies would, during the cooling of a sample, migrate with vacancies toward grain boundaries (vacancy sinks) and thereby enhance the solute concentration in boundary regions. For solute atoms which are not attracted to vacancies no such boundary solute enrichment would be expected. These concepts were given experimental support by boundary and bulk mi-crohardness measurements of various thermally treated dilute zinc and lead alloys and also doped aluminum oxide. The underlying assumption in their work was that solute enrichment in boundary regions is indicated by higher microhardness values. From thermodynamic considerations1&apos;2 it appears that the solid-liquid solute distribution coefficient (K), defined as the concentration of solute in the solid to the concentration of solute in the liquid at equilibrium, indicates whether attractive or repulsive forces exist between vacancies and solute atoms. K < 1 indicates a solute-vacancy attractions, K > 1 indicates no, or a repulsive, vacancy-solute interaction. This note is to report on observations of different grain boundary etching phenomena in high purity zinc alloys. These phenomena appear to depend on whether a K < 1 or K > 1 solute is present. In experiments designed to measure directly the solute enrichment in grain boundary regions, samples of zone refined zinc with 0.1 at. pct solute additions were cooled from 380°C at a rate of 3°C per min. A surface layer of approximately 50 was then removed from the samples by chemical polishing. The samples&apos; surfaces were then protected by a chromating treatment such that in a subsequent etch only grain boundary regions were dissolved. The dissolved regions were approximately semicircular troughs, 10 µ in width. The grain boundaries were usually in the middle, i.e., at the bottom, of this trough. For zinc containing the K < 1 solutes cadmium and aluminum, the grain boundary was always indicated by a ridge as shown in Fig. 1. For pure zinc, and zinc containing the K > 1 solutes copper and gold, a groove at the bottom of the trough indicated the boundary position, Fig. 2., To test if these different grain boundary etching behaviors were possibly connected with the segregation process discussed above, the Zn-Cd alloy was again heated to 380°C and quenched into brine. After surface protection and etching it was found that this specimen no longer exhibited the grain boundary ridges but rather grain boundary grooves as shown in Fig. 2. It would appear, therefore, that the boundary ridge is a consequence of a process occurring during the slow cooling of the samples. From absorption spectrophotometric analysis it was found that for slowly cooled samples containing K < 1 solutes, the solute/zinc ratios of the material from the boundary trough were consistently considerably higher than the solute/zinc ratios of the bulk alloys. This boundary region solute enrichment was not observed in quenched samples. It is concluded therefore, that the boundary ridge shown in Fig. 1 is directly or indirectly connected with nonequilibrium solute segregation.

Jan 1, 1970

The principal activities of the Bureau of Mines Explosives Research Center from July 1, 1962, to June 30, 1963, are described briefly in part 1. Part 2 gives short abstracts of publications that appeared during fiscal year 1963; in general, the research reported in these publications antedates the report period.

Jan 1, 1965

By James F. Kelly

"Research and development on the production of liquid fuels from coal is rapidly expanding worldwide. AImost every industrialized country is engaged in coal liquefaction research and process development. In Canada, the federal government, through CANMET, is actively supporting coal liquefaction research and development in a number of areas.A review of the basic principles and some of the processes in the production of liquid fuels from coal is presented with reference to the characteristics of the Canadian coal resource base. An overview of the CANMET coal liquefaction contract program is presented and specific results from the batch autoclave studies carried out with Saskatchewan lignite and Nova Scotia high-volatile bituminous coals are discussed. The development of a laboratory-scale continuous-flow coal liquefaction unit at the Energy Research Laboratories of CANMET to investigate the co-processing of coal and bitumen/heavy oil is also described.IntroductionThe CANMET coal liquefaction program is made up of two interrelated parts. The first part consists of the research and development work being carried out at the Energy Research Laboratories near Ottawa, Ontario. The second focuses on contracted research and development as part of the Coal Conversion Program of Energy, Mines and Resources Canada. The long-term objective of the liquefaction program is to contribute to Canadian liquid fuels production through the definition, research, development and demonstration of different coal liquefaction technologies for the Canadian marketplace.In coal liquefaction, the main objective is to produce liquid hydrocarbons with a higher hydrogen-to-carbon (HIC) ratio than the coal feedstock while reducing heteroatom (S,O,N) content, removing mineral matter and minimizing gas production. Typical atomic HIC ratios for a variety of Canadian fossil fuels are shown in Figure I. Canadian coals have about 500/0 of the HIC ratio present in tar sand bitumens and heavy oils and only about 20% of the ratio available in methane. In general, the cost of synthetic fuels production is related to the cost of hydrogen and, therefore, to the increase of HIC ratio between feedstock and products. On this basis, the production of liquid fuels from coal would be expected to be more costly than liquid fuels produced from bitumens and heavy oils. However, for mined tar sands and some heavy oils this difference tends to be offset by the large sand content (>90 mass %) of tar sand bitumens and the increased production costs of viscous heavy oils. For example, it can easily be shown that for equal weights of distillate <525°C) yield, current coal liquefaction processes required between two and three times less mined coal by weight than the mined tar sand s required for the most technically advanced processes proposed for bitumen upgrading."

Jan 1, 1981

By George Rice

THE A.I.M.E. Ground Movement and Subsidence Committee, pro-posed in 1920, held its first technical meeting in February 1923, under the able chairmanship of Mr. H. G. Moulton. The following list of papers and discussions, indicating the scope of the problems and relation to various conditions and method of mining, were given at that meeting by the distinguished mining engineers: J. Parke Channing, on Subsidence at Miami, Arizona; Howard N. Eavenson, on Mining an Upper Bitu-minous Seam after a Lower Seam Has Been Extracted; J. J. Rutledge, on Subsidence in Two Oklahoma Coal Mines; Benjamin F. Tillson, on Caving Cracks at the Franklin Mine, New Jersey; Dr. F. W. McNair, on the Dome Theory; William Kelly, on disadvantageous effects in Mining and Back-filling Working Upward a Steep-Pitching Iron-ore Bed; Eli T. Conner, on the good results of Back-Filling by Hydraulic Means in Preventing Destructive Subsidence in the Anthracite District; Thomas H. Claggett, on the merit of Systematic Pillar Drawing in Preventing Cracks in an Upper Seam; Henry H. Otto, successful results in the anthracite district in Mining Lower Seams before Upper Seams; Douglas Bunting, on Leading Factors Incident to Successful Mining of an Overlying Seam; Edwin Ludlow, on there being "less damage to buildings when there was complete removal of coal with complete packing than when room and pillar is used without extracting the pillars"; Edward O&apos;Toole on "bumps" in eastern Kentucky mines, which he thought were the result of geologic stresses: H. A. Buehler, on Upheaval of Surface in an Illinois Case in Advance of the Face; and R. Dawson Hall, on The Mechanics of Subsidence from Mining. The author of this paper discussed various Winds of problems of ground movement and subsidence in both metal mining and coal mining; the production of great landslides by workings near an outcrop, as at Turtle Mountain, Alberta, Canada; and general

Jan 1, 1939

By C. D. Anderson, C. G. Anderson, P. R. Taylor

"Rare Earths have become critical for our energy and materials driven society. While primary production must ramp up to fill growing demands, the recycle of these strategic elements must also be initiated. This paper will outline the potentials of and metallurgical technologies employed for Rare Earths recycle from various secondary sources.INTRODUCTIONWhen investigating the recovery of rare earths from secondary sources it is necessary to understand the nature of the sources to be processed. As of 2009, the USGS reports the distribution of rare earths by end use, in decreasing order, was: chemical catalysts 22%, metallurgical applications and alloys 21%, petroleum refining catalysts 14%, automotive catalytic converters 13%, glass polishing and ceramics 9%, rare earth phosphors for computer monitors, lighting, televisions 8%, permanent magnets 7%, electronics 3%, and others 3% (USGS, 2011). Additionally, it is reported that the amount of recycling was quite small and consisted primarily of rare earth magnet scrap, although with the sharp increase in the price of rare earths, and the potential shortage in supply, focus in this area is continually growing. Thus, the opportunities, whether realistic or not, are extremely vast in the recycling of rare earth containing materials. The following subsections will present methods proposed for the recycling of rare earths based on the feed material type.RECYCLING OF RARE EARTH MAGNETSCurrently, investigations are ongoing in the area of recycling production scrap and end-of-life materials in the rare earth magnet industry. The following techniques illustrate potential methods for the recovery of rare earths from secondary RE magnet sources.Recycling of Rare Earth Magnet Sludge by Selective ChlorinationDuring the production of neodymium magnets, a by-product of production is the so called “magnetic sludge”. This by-product contains high amounts of neodymium, thus a process for the recovery of Nd has been proposed. In this process the Nd present is selectively chlorinated/distilled by the addition FeCl2 via the following reactions."

Jan 1, 2012

By John Jermain Porter

The chief purpose of this paper is to indicate the laws governing the fuel-economy of the cupola, to examine the feasibility of some of the proposals for increasing its fuel-economy, and to show that the conditions limiting fuel-economy here are altogether different from those prevailing in the blast-furnace. The two methods available for studying the thermal efficiency of the cupola and determining the factors limiting fuel-economy are: 1, by the determination of the total heat-balance; and 2, by the application of the theory of critical temperatures. The case selected as an example represents a cupola operating under fairly efficient conditions. The data are as follows : Cupola, GO in. in diameter, 15 ft. high to the charging-door, with a 9-in. lining. Bed-charge, 2,000 lb. of coke and 4,000 lb. of iron. Subsequent charges, 400 lb. of coke and 4,000 Ib. of iron. Total number of charges, 20. There was 800 lb. of coke recovered from the drop, hence the total coke burned is 8,800 lb., or 0.11 lb. of coke per Ib. of iron. Coke contains 90 per cent. of fixed carbon and 2 per cent. of moisture. 300 1b. of kindling-wood is used in lighting. 80 lb. of limestone (95 per cent. of CaCO,) is used per charge, or 0.02 lb. per Ib. of iron. Melting-loss, 4 per cent.; distributed thus : Fe, 3.5; Si, 0.25; Mn, 0.25 per cent. Average analysis of top-gases : CO2, 15.1; CO, 10.0 per cent. Average temperature of top-gases, 1,600" F. Temperature of air and stock charged, 60" F. Dew-point of air, 50 F. The items entering into the total heat-balance and their calculation are as follows: 1. Heat of combustion of fuel.—Total heat evolved = 14,580 x lb. of carbon burned + 7,200 X Ib. of wood burned. Hence B.t.u. per lb. of iron charged =

Jan 1, 1913

By R. P. Nicholson

On September 3rd, 1947, the Acadia Coal Company put into operation a central coal preparation plant. This plant was designed to process all coals mined by this Company in the Pictou County coal field. The problem, briefly, was to make a three-way separation of the raw coal fed into the plant. It was desired to remove all stone, metal, and wood from the marketable coal and to produce a splint coal from the raw material which would be suitable for making power. This splint coal product is belted directly to the power plant which is adjacent to the wash plant. To attain this object it was therefore necessary, first, to wash the raw coal, removing all splint, stone, metal, and wood. The stone, metal, wood, and highest-ash splint had then to be removed by a second washing in order to obtain the lower-ash splint for use in the power plant. The plant is on the east side of the Allan colliery, in the town of Stellarton (see accompanying photograph). It is of steel frame construction with wood siding, covered on the exterior with corrugated galvanized iron. Considerable concrete had to be poured for the foundation piers as the plant site is largely &apos;fill&apos; ground. This necessitated the construction of extremely heavy footings containing a large amount of reinforcing steel. In all, 884 cu. yds. of concrete were poured for the various pits, tanks, and foundations; its average test was about 3,500 lb. per square inch. At the time the plant was constructed, the steel shortage in Canada and the United States was acute and, in order to obtain steel for the structure which is four stories high- an unused part of the Allan bankhead was torn down. Enough steel was obtained from this demolition to fabricate the new plant.

Jan 1, 1948

The October General Meeting of the Institute was held in Kelvin House, Johannesburg, on 15th October, 1969, at 4.30 p.m. Mr J. K. E. Douglas (President) was in the Chair. There were also present 17 Members, Messrs: M. Barcza, R. C. J. Goode, J. A. Nixon and V. C. Robinson (Council Members), M. L. Fitzgerald, D. F. H. Graves, C. G. Hinds, S. D. Hill, J. S. Hall, D. F. Malan, T. Meyer, W. pyne-Mercier, K. S. Rae, S. G. Taussig, L. W. P. van den Bosch, Dr A. Whillier, C. H. Wyndham. Four Associate Members: Messrs O. Davel, M. J. Martinson, M. P. J. Sandys, T. G. Harington. One Student: R. P. W. Henrard. Three Visitors: Messrs A. V. Pike, B. Schmitz, A. P. Raats. Secretaries: D. C. Visser and S. de. Gersigny. Total present: Twenty-eight. OBITUARY The President: "It is my said duty to announce the death of Pieter Ulrich Fischer, Member, who joined the Institute in 1961 and passed away on 24th June, 1969. As a mark of respect to the memory of the deceased and in sympathy with the bereaved I would ask you all to rise and observe a few moments&apos; silence." MINUTES The President: "The minutes of the last meeting will only appear in next month&apos;s Journal and I would request that the confirmation of these minutes be held over." MEMBERSHIP The President: "I have much pleasure in announcing that the names of the undermentioned candidates, having been published in accordance with By-Law 5.2.2, Council has elected them to membership of the Institute in the following grades:" Members: Alexander Edward O&apos;Meara, Anton Leopold Melvill, WilIiam Harold Wise, Eric John Dunstan, Frank Nel, Lubertus Hendrikus Jakob Poortier. Associate Members: Michael Irvine Britten, Selwyn Wilson Lange. James McCormack, Christiaan Lodewyk de Jongh, WilIiam Andrew Hustrulid, Reinhold Johannes Ortlepp, Felix Henry Lancaster. Graduates: Willem Adriaan Gericke, Hamish David Sneddon Miller, David lan Ossin, Robert Antony Layboume, Ewart John Shillaber, Colin Hewitt Wiggett. Affiliates: Bernard Andre Thomas, Waiter Arthur Wood, Andrew John George Paschalides, David John Perry, Alex Richardson, Gert Blekker Kotze. Student: Matthys Jacobus de Beer. MEMBERS TRANSFERRED TO A HIGHER GRADE From Associate Member to Member: David Alphonso Viljoen. From Student to Associate Member: Michael Charles Carruthers. "I welcome the newly elected members to the Institute and congratulate the members who have been transferred to a higher grade." PAPERS FOR PRESENTATION The President: "Professor Wyndham, may I call on you to deliver the paper entitled &apos;Factors affecting the mechanical efficiency of men shovelling rock in stopes&apos;, written jointly with J. F. Morrison, J. H. Viljoen, N. B. Strydom and A. Heyns." After the presentation of the paper the President said: "Gentlemen, I would like to thank Dr Wyndham and his colleagues for once again reporting through the medium of this Institute the results of the very important work they are carrying out at the Human Science Laboratories. It is most appropriate that this work which is leading to a better understanding of the capabilities and efficiency of the human body under the arduous conditions encountered underground should be reported to this forum. In this way our members, who are actively engaged in the job of mining, can firstly learn something of this research and secondly, can, with their practical knowledge of conditions underground, contribute to what has been learnt and possibly pose new problems for our scientists in the laboratories. The scientist should always have the opportunity of subjecting his research to the scrutiny of people engaged in practical operations. By the very nature of our gold mines we are unfortunately heavily dependent on a large labour force and while mechanization has been introduced wherever feasible, we are likely to continue to be heavily dependent on this labour. In accepting this fact we can be proud in this country of what has been achieved, not only in obtaining the best efficiency from labour but in ensuring that their working conditions are reasonable and that their health and well-being are adequately cared for. When one visits our gold mines, one cannot help being impressed with what is being done to ensure that we have a satisfied, happy and healthy labour force. The Human Sciences Laboratory with its scientific approach has assisted greatly in promoting a better understanding of the problems associated with labour under the conditions experienced on our mines. Thank you." Mr M. Martinson then contributed to the discussion. (This contribution will appear in a later issue of the Journal.) "Professor Wyndham, may I call on you to deliver the paper entitled &apos;Acclimatizing men to heat in climatic rooms on mines,&apos; written jointly with Prof Strydom." After Dr Wyndham had presented the paper the President said: "Thank you Dr Wyndham for so ably describing the work associated with the acclimatization procedures on our gold mines. It has certainly been an eye-opener to those of us not familiar with this work and I believe it is very important that everyone and not only people in the gold mines should know about it. It is fortunate that all industries do not have the same arduous heat conditions experienced on our mines but other industries such as our chemical and metallurgical industries do have other problems relating to the adjustment of labour to the work situation. The scientific approach employed by the gold mines in tackling this problem is an example to these industries of what can be achieved by logical

By K. Mikulash

"Agnico-Eagle Mines Limited is located at Joutel in North-Western Québec. The mine is about four miles north-west from the town on the left bank of the Harricana River. The present mining is 1,800 feet deep with an extensive geological development below this level.HISTORY The development of the ore body started sometimes in 1967 and then the operation ceased in 1969 and again reopened in 1973 due to higher prices of gold. During these periods of active development, a considerable metallurgical research has been done by different laboratories and research and design companies.The original capacities of the Mill differed as much as 30%. So did the concept of the ore treatment. The original design of the mill was for 200 TPD of ore with straight cyanidation. The problems with low gold extraction, high reagent consumption and poor filtration resulted in a decrease of the expected mill output to an initial 550 TPD with gold recoveries in the order of 40 to 60%.Although the studies and research work done on the ore varied, all of them had a common conclusion: a very fine grind is needed to expose gold. The mining method (sub-level blast hole mining) now provides the ore that differs from that on which the metallurgical test work was conducted and the original capacity calculations had been done.These variations in the concept consequently led to the conclusion that the size of gold is a determining factor for the process.Kilborn Engineering provided the original design with the Leslie Eng¬ineering completing the design. The metallurgical test work has been done by the Department of Energy, Mines & Resources, Lakefield Research of Canada, Kilborn Engineering and Sidam Incorporated.The new flotation section with secondary grinding has been designed and put into operation by the company in December 1975 with the results yet to be evaluated."

Jan 1, 1976

By Fred Bond

THE process of comminution by grinding is properly classified as an art, rather than as a science. Like most other operations concerned in ore dressing, or in the treat-ment of nonmetallic minerals, the mathe-matical relationships of rock breaking are still obscure, and much disputed. If some basic formula exists, comparable for in-stance to E = RI in electricity, it has not yet been placed in common use. The absence of such a comprehensive mathe-matical background undoubtedly is the cause of many inefficient designs and installations, as well as of much poorly oriented experimental work. On the other hand, the mathematical immaturity of the process constitutes an opportunity for a real contribution on the part of those who enjoy mental pioneering. Some of the statements made in any such exploratory work may be little more than opinions, and it is to be expected that some will later be proved untrue; but such an evolutionary development is necessary if we are ever to arrive at the fundamental laws, the discovery of which can change the empirical art into a mathematically exact science. The most significant principle of com-minution that we possess is probably Rittinger&apos;s law, which states that the work done in crushing or grinding is proportional to the area of the new surface produced. There is an alternative theory, known as Kick&apos;s law, which formerly was preferred to Rittinger&apos;s but which now is rather dis-credited. According to Kick, the work done in comminution is proportional to the volume, or weight, of the pieces broken, or to the cube of their diameters, while accord-ing to Rittinger it is proportional to the square of the diameters.

Jan 1, 1940

By V Kumar, A S. Venkatesh, R K. Upadhya

The enormous iron ore deposits of eastern India are part of the volcano-sedimentary basins containing iron and to some extent manganese deposits that belong to the Iron Ore Group (IOG) of Archaean Singhbhum Craton, occurring as western and eastern limbs of a broad synclinorium. The eastern iron basin contains typically huge amounts of blue dust and powdery ores. There is a remarkable difference between the western flank ores and the eastern flank ores and the present study is part of the eastern flank ores from Noamundi. Demand for sintered fines as blast furnace feed coupled with the higher export price for lumpy ores that produce enormous amounts of fines during processing has created a situation whereby both primary and secondary fines, such as classifier fines, are being increasingly used as sintered feed for blast furnace. Systematic mineralogical and geochemical characterisation indicates that in many cases the ROM and classifier fines have to be processed to increase their Fe content and at the same time reduce their Al, Si and P contents. The fines which are already at micron sizes are amenable for beneficiation using the Mozley mineral separator and sink float test. It was observed that beneficiation was better and significantly greater by the sink float method than the Mozley mineral separator. Mineralogical and chemical studies of the fines reveal that around 80 per cent of alumina bearing minerals (gibbsite, clay and silicates) are present in the liberated form. Microscopic studies confirmed that the iron minerals are well liberated by controlled grinding to -300 mesh sizes with the beneficiation of iron ore fines and low-grade ores carried out using the Mozley mineral separator and sink float test. Beneficiation using the Mozley mineral separator increased the grade of concentrate with increasing flow rate of water as well as increase in amplitude of oscillation of the tray, but not very significantly with the increase in slope of the tray. In this method, though, iron concentration improved from 47 to 63 per cent with a recovery of around 67 per cent. It is not suitable for industry scale operation as only a small quantity of ores can be handled at a time. Beneficiation using the sink float test produced a better result with the Fe content increasing from 47 - 49 per cent to 66 - 68 per cent with a recovery of approximately 58 per cent. Initial feed Al2O3, SiO2 and Fe contents of 9.85 per cent, 15.3 per cent and 49.8 per cent respectively were beneficiated to 2.13 per cent Al2O3, 1.5 per cent SiO2 and 67.5 per cent Fe in the concentrate, with a recovery of 54.1 per cent. In contrast, using the Mozley table resulted in beneficiable contents 66.3 per cent Fe, 3.01 per cent alumina and 2.05 per cent silica. The combined alumina and silica content for the Mozley Table was >5 per cent, which exceeds the industry requirement of

Jan 1, 2005

By A-A Latscha, C Boyle

Geological modelling has historically been done using sectional interpretation of paper sections or on a computer screen. Boundaries of geological units or grade shells are interpreted by a geologist section by section and the shapes are drawn onto paper to be digitised later or they are directly digitised into a computer. This approach is referred to as explicit modelling. Such methods are time consuming if there are many section lines or boundaries to be interpreted. The number of metres drilled and resource models made is increasing each year and it will be difficult to keep up using explicit modelling methods. Alternatively, it is possible to use information carried in the drill holes, known geological relationships and point estimation methods in two or three dimensions, to create similar geology boundaries, while eliminating or at least greatly reducing the need to manually interpret and digitise detailed sectional interpretations. Such methods are referred to as implicit modelling and are available in a number of software packages. Implicit modelling approaches have been used in iron ore and found to significantly reduce the time needed for modelling while producing results that are comparable or better than standard explicit modelling approaches. A number of case studies have been undertaken of implicit modelling in iron ore deposits. Stratigraphic surfaces of bedded, folded and faulted iron ore deposits have been modelled in various deposits by Leapfrog Geo, GOCAD (with SKUA) and Vulcan Integrated Stratigraphic Modelling. Leapfrog Mining was used to model iron grade shells at particular cut-off grades. The modelled surfaces are of a high standard equivalent to those that could be produced by traditional explicit modelling but the time required by the implicit methods is far less. Implicit geological modelling is an active area of software development and improvements in software are likely.CITATION:Boyle, C and Latscha, A-A, 2013. Implicit geological modelling of iron ore deposits, in Proceedings Iron Ore 2013 , pp 57-66 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

WILDER D. BANCROFT,* Washington, D. C. (written discussion?).¬In two-phase systems there are three possibilities and Mr. Alexander has only considered two. We may have the first phase the internal one and the second the external one; we may have the first phase the external one and the second phase the internal one; and we may have both phases continuous. This last case occurs when we have a roll of wire fencing standing in the air; the wire is continuous and so is the air. It is quite probable that this case occurs very often in alloys and it it, therefore, important that it should not be overlooked. With gulch,

Jan 3, 1919

By M. A. Hosmer, Job Goostray, R. F. Harringon

In this paper, as in so many discussions of an historical nature, there is little chance for original material and much has had to be rewritten from older papers, documents, accounts, reports, and the like, some of which are of doubtful authorship or contain conflicting statistics. Fully aware of these pitfalls, the authors have tried to quote the origin where possible, and also to seek further confirmation when the statement warranted it, but they cannot assume responsibility for certain facts and dates. The Encyclopedia Britannica was frequently consulted. The authors wish to acknowledge assistance from Mackintosh-Hemp-hill Co. (formerly the Fort Pitt Works) and also from officials of the Watertown Arsenal who loaned valuable books and gave much necessary information. They are particularly indebted to Colonel Dickson of that institution. The data on modern guns were furnished by Mr. F. Brauer of the Watertown Arsenal; Mr. H. S. Chaffee assisted by obtaining records and data of work carried on by the Builders&apos; Iron Foundry of Providence, R. I. Three Epochs in History of Cannon Among the great industries of New England, the manufacture of iron was the first to receive attention. Iron ore in considerable quantities was known to exist within the territory of the Massachusetts Bay Colony; and as early as 1629 some steps appear to have been taken toward the manufacture of iron by the Court of Assistants in London, under whose patronage the colony was founded. During the next ten years, deposits of bog ore were found in numerous ponds in the Plymouth Colony; and, in 1652, iron manufacture was begun at Raynham. The "Old Colony" was known as the main seat of this industry in New England, out of which grew a concern which was later to become one of the principal

Jan 1, 1925