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By Kirkhouse C. B

Soon after the Broken Hill Limited started operations at their Iron and Steel Works at Newcastle, NSW, it was found necessary to install a mill for rolling small merchant bars, rounds, etc.An arrangement of the first mill laid down is shown on Plate 1., Fig. 1. This mill commenced operations on the 18th July, 1917.The feed for this mill was rolled in the existing 18-in. mill and sheared to the lengths required before being delivered to the billet storage yard. The billet storage yard is 90 ft. span, and is served by one 10-ton electric overhead travelling crane. Billets were placed on the billet bed preparatory to being charged into the heating furnace.The heating furnace was of the continuous recuperative with end discharge and had a hearth 40 ft. long by 10 ft. wide. The billets were pushed through the furnace by means of two hydraulic rams, which could either act together and push one row of billets, or act singly and push two rows of billets. This furnace was fired by producer gas from the producers shown on Plate I., Fig. l.The gas was conveyed to the furnace by means of a brick underground flue.

Jan 1, 1935

By Walker E. R

IN the early age of steel it was made hy what is known as the cementation proeess, in which wrought iron was embedded in charcoal and heated in a mufflc furnace to a tcmperature of approximately 1100° C. for varying lengths of time, the length of time depending upon the amount of carbon (or better known in thosedays as the degree of hardness) required in the finished product.By this process the resultant product obtained was not of uniform quality, and because of this uncertainty of quality Huntsman was induced, in the year 1740, to introduee what is known as the crucible process.This process consisted of cutting into small pieces the product of the cementation process, placing these pieces in a crucible, and melting them down with the aid of a eoke-fired furnace, after which the molten metal was cast into suitahly shaped ingots, from which could be hammered any desired shape.A section of crucible furnace is shown in Fig. 1. By this means a product, very uniform in character, was produced.The process is still in use, but, owing to its high operating cost, it is mostly eonfined to the production of very high-grade carhon and alloy steels. Its position to-day as a producer of these high-grade steels is, however, being very seriously challenged by the electric process.It was owing to the excessive cost of crucible steels and the need of producing a steel in commercial quantities and at a reasonable cost, that led Sir Henry Bessemer to introduce what is known as the Bessemer process.

Jan 1, 1930

By Holdgate G. R, Thompson B. R, Webster R. L, Bolger P. F

The Gippsland Basin in south-eastern Australia has an area of approximately 46 000 sq km. It is one of the world's major coal and petroleum bearing basins, with most of the former occurring in the smaller one fifth on-shore part. The stratigraphy, structure and economic resources of the Tertiary sedimentary pile is now well known through extensive drilling for coal and petroleum. In contrast, the older Cretaceous sequences through their lesser economic importance are relatively less explored. The sedimentational history of the Gippsland Basin has largely followed along similar lines of development to the many other southern Australian basins since the Cretaceous break-up of Gondwanaland. However, the scale of accumulation of coal and hydrocarbon source rocks is unprecedented and differentiates this basin, for reasons less well understood, from the others. Large scale open cut brown coal mining since the late-1920s has been carried out in the western extremities of the basin, while vigorous extraction of some two thirds of Australian petroleum products taken place in the offshore part. Brown coal seam thicknesses and economically winnable reserves are huge and outrank most other brown coal basins of the world. Development of the resource currently meets the need for electricity generation throughout the State of Victoria, but other future developments such as conversion to oil, being investigated.

Jan 1, 1992

Indigenous brown coals, which provide a readily available primary energy source, have played a significant part in the industrial development of Victoria. The deposits located in the Latrobe Valley compare in extent with other major deposits of brown coal in the world. Smaller but valuable deposits occur at Stradbroke, Gelliondale, Anglesea and Bacchus Marsh. Extensive drilling, aided by geophysical surveys, and detailed analyses of coal samples, have enabled the extent and quality of these Tertiary deposits to be Defined.

Jan 1, 1979

By J. M. Locke

BRÜCKNER's revolving cylinders for roasting ores, etc., are now used at a number of the mills in Colorado and New Mexico, for the purpose of roasting and chloridizing silver ores, with highly satisfactory results, even from those cylinders of small size, erected before the many improvements of recent date. As examples of the larger improved cylinders, reference can be made to those erected at the Tennessee Reduction Works, Silver City, Grant County, New Mexico, and those which were built, in 1871, at the celebrated Caribou Silver Mill and Mines, Colorado, a mining enterprise which has proved so satisfactory as to have been lately sold to a Holland company for an enormous amount. These cylinders, as now constructed by Messrs. Lane & Bodley, of Cincinnati,, Ohio, are shown in Plate III, in which Fig. 1 is an elevation in perspective, Fig. 2 a longitudinal, and Fig. 3 a trans¬verse section. Fig. 4 is a sketch of a mill, with Brückner's cylinder. The exterior of the cylinder is a shell of boiler iron, 12 feet long by 5 feet 6 inches in diameter. The ends are partially closed with similar material, leaving in the centre a circular opening about 2 feet in diameter, bounded by a flange projecting several inches.. Upon one side is placed an opening closed by a hinged door. Upon the outside of the cylinder are bolted three bands, as shown in Fig. 1, in which the section of the first is square, and that of the third semi¬circular; the second, or middle band, is a strong spur gear. Passing through the cylinder are six pipes parallel to one another, in a plane at an angle of 15° to the axis of the cylinder; these pipes also lie in this plane at an angle of from 30° to 35° to the longitudinal, axis of the plane, as shown in Fig. 2, where the internal arrangement of the cylinder is seen, a perforated diaphragm being formed through part of the cylinder by means of perforated plates placed between

Jan 1, 1874

By T. Nishi, D. Teguri, K. Saitoh

In recent years the requirement for high carbon ferro-manganese (HCFeMn), which is the key product of our company, has increased due to bullish demand for steel products. In our Tokushima works, we have 2 closed types of electric furnaces (1F and 2F), with which we are manufacturing HCFeMn. In order to meet the increase in demand, we made various modifications to these furnaces and we tried to increase the furnace operating loads. Especially for 1F, we deepened the furnace. In this paper, we report the results of this modification. The operational situations of the above-mentioned two furnaces are different because they have different individual profiles. As for 1F prior to modification, the depth of the furnace was one meter shallower than2F, because 1F was designed for the manufacturing of SiMn. On the other hand, our Tokushima works specialized in HCFeMn 14 years ago. However, the profile of 1F was not optimized for HCFeMn. In comparison to 2F, 1F was more difficult to stabilize due to the smaller tolerance for the adjustment of the electrode length, the metal / slag level, and the coke-mixing ratio. We deepened 1F by 770mm by disposing of the furnace rolling mechanism. We consequently achieved a 10% increase in production capacity. This meant the operating load was enhanced from 24.5MW to 27MW, the furnace became more stable and the tapping speed of both metal and slag increased, all which made the tapping easier than before.

Jan 1, 2007

Dimension stone is the term generally given to rock used in building construction. During early European history in Otago, locally available dimension stone products were easily obtained. Crude rock shelters built on river banks with schist rock within Central Otago soon gave way to more established and sophisticated permanent homesteads constructed with the same materials. Victorian architectural achievement is celebrated in Otago with many fine bluestone block buildings. When the University Council decided to build substantially in stone, it narrowly escaped disaster. It was well known at the time that brick in Dunedin was of an inferior quality and that it soon wasted. Rev Dr Stuart said before the 1879 Commission that æthe Council had some old-world notions and liked to have the University with some architectural styleÆ. Contemporary utilisation of dimension stone is generally restricted by expense to a simple veneer. Stone products produced from Otago quarries have found ready markets in other areas in New Zealand , particularly prior to the share market crash in 1987.

Jan 1, 1992

By Associates

The headwaters of Skippers Creek and the Shotover River are reputed to be among the richest alluvial gold catchments in the world. This alluvial gold has no doubt been derived from reef systems similar to, and associated with, the Bullendale lodes. Physiographically the prospect covers steep ridges and deeply incised gullies between the Richardson Mountains in the west and the Harris Mountains in the east. Vegetation is mainly tussock with bush either side of Murdochs Creek. Access to the area is by metalled road to Skippers and then by 4WD track to Bullendale. Alternatively the prospect area can be reached by helicopter from Queenstown in around ten minutes.

Jan 1, 1992

By Catherine C. Kilgore

The Bureau of Mines investigated the availability of fluorspar from 35 domestic and 50 foreign, mines and deposits in 13 countries. Only 6 domestic properties are considered to be economic reserves, as 29 domestic deposits were found to have an average total cost of production that was uneconomical at a breakeven (0 pct) DCFROR. The 50 foreign properties evaluated were selected to represent at least 85 pct of the known demonstrated fluorspar resources located in market economy countries and China. All evaluated foreign operations were found to be economic to marginally economic in January 1984 dollars. World demonstrated ore reserves of 344 million metric tons (mt) containing 123 million mt of CaF2 were evaluated for the 56 operations. Average total costs needed to cover all costs over the life of each operation were determined for all recoverable fluorspar products. Comparisons of mining, beneficiation, and transportation costs per mt of fluorspar concentrate illustrate advantages between countries. Of the three largest producing countries, China, with its high-grade, low-cost operations had the lowest weighted average total cost of production ($38/mt concentrate). Mexico was next at $54/mt concentrate, and South Africa needed an average of $90/mt of concentrate to cover all costs of production for its low grade deposits.

Jan 1, 1985

By R. Hope, C. van Heerden

In any process or organization inefficiencies are costly. In times of abundance this reality often does not receive much attention. During such times the focus is rather on increasing capacity to increase production. However, there is a growing awareness in the world of tougher economic, social as well as environmental conditions, and enterprises find themselves facing greater demands for accountability towards shareholders, the environment and the public, as well as growing competition for market share and limited global resources. This reality is no different in ensuring a sustainable mineral sands operation. In order to achieve this, any operation needs to be stripped of all process as well as operational inefficiencies. In this context it has become essential for any Mineral Separation Plant (MSP) to have the necessary process monitoring and control systems in place to continually monitor and optimize the production of on-spec products and maximize operational efficiency and consistency. The MSP Grade Control Solution developed by Crusader Systems and running on top of the CSense platform contributes towards these goals by improving the consistent production of on-grade product. This allows the process to operate closer to the maximum allowable product grade constraint, which in turn maximizes production.

Jan 1, 2003

By Zachary Mayer

Agenda ? Kidd Mine ? Background ? Problem & Opportunity ? Challenges associated to depth - Production Rates - Productive Work Time - Operational Delays - Transfer Levels - Mucking Time - Impact on Hoist ? LHD Automation ? Sandvik AutoMine Lite ? Expected Benefits Kidd Mine - Background ? Located in Northern Ontario, Canada ? Underground base metal mine operating since 1966 ? Total 148 Mt mined (2.31% Cu, 6.08% Zn, 75 gpt Ag) ? 2.35 Mt/Y from stopes as deep as 9500 ft (2.9km) below surface ? Mining method: blasthole open stoping ? Mine/Mill: 1263 employees and contractors ? 2012 National John T. Ryan Safety Award

Aug 1, 2013

The fundamental features of the Cable Belt Conveyor are described. It consists of independent wire ropes which take the transmission load, and a special reinforced rubber belt which acts 'only as carrier of material. The first cable belt installation in Scotland is described briefly.A general description of this type of conveyor is followed by details of the rubber belt construction and the method of joining sections of belt. The drive unit, the tensioning arrangements and the power requirements are outlined.Applications of the cable belt conveyor are 'dealt with and its advantages summarized.INTRODUCTIONThe cable belt conveyor, as its name implies is a conveyor composed of steel wire ropes and a rubber belt, in which the ropes serve as transmission members, and the belt merely as a carrier of materials.Over the years it has been the ambition of engineers connected with the belt conveyor industry to develop a conveyor that would use the high tensile strength of wire ropes to transmit the stresses involved in the driving of large capacity belt conveyors. Different lines of approach have been adopted in the United States of America and in Britain. In the United States the method adopted was to introduce a large number of flexible steel cables into the rubber belt itself, in the form of a closely packed layer arranged across the full width of the belt. These small cables are packed in a nylon filled duck envelope which is incorporated in the rubber belt. This is commonly known as the steel corded conveyor belt. In Britain, a Scottish firm developed a rubber belt conveyor in which full advantage was taken of the high tensile features of wire rope, without embodying or moulding the wire rope into the rubber belt, so that the two wire ropes and the rubber...

Jan 1, 1957

The Cadjebut Mine is located 80 km southeast of Fitzroy Crossing. Cadjebut is owned 58 per cent by BHP Minerals and 42 per cent by Billiton Australia. Cadjebut is a 'Mississippi Valley Type' (MVT) deposit. Minerals present are sphalerite, galena and marcasite in a sedimentary host of dolomite and siltstone. The ore contains few deleterious impurities and no silver. The mill was commissioned in the first half of 1988 at a rate of 320 000 tonnes per annum. An expansion in the latter half of 1989 has since increased production to 550 000 tonnes per annum. The initial geological resource at the commencement of mining was 3.8 million tonnes at 13.5 per cent Zn and 4.4 per cent Pb. There is sufficient ore left to sustain operations to 1995 at a grade of 11.2 per cent Zn and 3.9 per cent Pb. The ore from underground is stockpiled on the surface via a drift conveyor and from the stockpile is fed into a grinding circuit consisting of a SAG and ball mill. Cyclone overflow at a Pgp of 90 pm gravitates to the flotation circuit. Lead and zinc are sequentially floated to produce an 80 per cent Pb grade at 90 per cent recovery and a 61 - 62 per cent Zn grade at 96 per cent recovery. The concentrates are thickened and filtered before being trucked to the port of Wyndham 600 km away. From Wyndham the concentrates are shipped to smelters in Asia, Europe and Australia.

Jan 1, 1992

By J Williamson, M Griessmann

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Watershed tungsten deposit is located in the Hodgkinson Province of north Queensland, Australia. The deposit is hosted by Siluro-Devonian flysch-type meta-sediments of the Hodgkinson Formation, which were subjected to four major deformation events. Mineralisation has occurred syn- to post-D4 and is related to the intrusion of S-type granitoids of the Permian Whypalla Supersuite.Watershed is located within a regional NW–SE-striking melange zone composed of brecciated and intermixed arenites and shales. The major NW–SE-striking Tullah fault zone is situated in close proximity to the east of the deposit.The Watershed deposit occurs within a tightly folded upright anticline with NW-plunging fold axis. The anticline contains a major package of coarse-grained to conglomeratic arenite, which harbours the Watershed mineralisation. Several alteration styles occur within the arenites, of which Fe-poor calc-silicate alteration dominated by clinozoisite/epidote is the most significant. Less widespread but locally important alteration styles comprise garnet-dominated calc-silicate alteration, albitisation and sericitisation. The arenites are enveloped by unmineralised carbonaceous shales and shale breccias.Tungsten mineralisation occurs solely as molybdenum-poor scheelite and can be found as three styles: disseminated mineralisation in calc-silicate altered arenites, vein-style mineralisation with quartz-albite-scheelite veins and minor but high-grade mineralisation in albitised felsic dykes.Contact metamorphic rocks and geophysical data indicate the proximity of an underlying granitic body. It is believed that this granitic body was the main driver of the hydrothermal system generating the Watershed deposit. An early mineralisation stage caused the selective calc-silicate alteration of the arenites, while a second stage caused the vein-style high-grade mineralisation. The folded shales enveloping the arenites worked as an effective barrier that kept the mineralising fluids in a confined rock volume.The scheelite mineralisation at Watershed is open to depth, with a granite-hosted porphyry or greisen-style mineralisation anticipated below the current resource.CITATION:Griessmann, M and Williamson, J, 2015. The calc-silicate-hosted Watershed tungsten deposit, far north Queensland, Australia , in Proceedings PACRIM 2015 Congress, pp 545–550 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By R. J. C. MacDonald

"The first recorded discovery of placer gold in Canada was on the Chaudiere River in Quebec's eastern townships in 1832 and the first major production came from placer deposits in British Columbia in 1858 (Verity 1974). Placer deposits were the major source of gold until the late 1890's, although lode deposits were found in Nova Scotia in 1862. In 1896 the Klondike Gold Rush commenced with the discovery of gold by Henderson and Carmack in the Yukon. The peak was reached in 1900 when over one million ounces of gold valued at approximately $22.3 million were recovered. With the exhaustion of the easily accessible deposits, more capital intensive operations were necessary such as those initiated in 1906 by the Yukon Gold Corporation. This giant dredging operation continued to produce until 1966. Today only a few small operations remain.The development of Canadian lode gold mining began in earnest around 1900 when the railroads were opening up the interior and western part of the country. At this time many discoveries occurred, particularly where mineral outcroppings were near surface. Tremendous impetus for exploration and the reopening of former producers followed the elimination of the gold standard by Great Britain around 1931, and more importantly the United States in 1933, with subsequent stabilization of the price of gold at $35 per ounce in 1934. Prior to this the price of gold was basically unchanged since 1717, approximately, $20 per ounce (Verity, 1974; Green, 1973).The depression of the 1930s adversely affected most industries, however for the gold producers it was a very profitable time. Prices of materials and equipment declined and labour was cheap and plentiful. Interest in gold mining was further stimulated in 1936 when a three year tax exemption was declared for all new metal mines. In 1938 a decline in the value of the Canadian dollar relative to the U.S. dollar benefitted the industry. The second world war provided yet again further incentive for gold production and in 1941 Canadian gold production reached a high of approximately 5.4 million ounces. This figure was not surpassed until 1991 when approximately 5.6 million ounces were produced (Natural Resources Canada, 1996 )."

Jan 1, 1998

Currently in Canada there are 15 major mining companies with a minimum of $1 billion in market capitalization or net private value. This group forms the core of an important sector for Canada. The mining sector had gross revenues of about $35 billion in 1988. This compares to a Canadian GDP of $410 billion in 1988. There are at least three different sub-groups within the mining group, each facing the future with very different prospects for the coming years.

Jan 1, 1989

By D. L. Ogonowski, J. O. Marsden

The Candelaria copper-gold mine is located approximately 25 km south and east of Copiapo in Region III, Chile. The original concentrator was designed to treat 28,000 t/d (30,800 stpd) of chalcopyrite-bearing ore through a circuit consisting of a single 11.0 m(36 ft) diameter SAG mill, two ball mills, conventional rougher and scavenger flotation, column cell cleaner flotation, and ceramic disc filtration. The plant was commissioned in August 1994 and quickly reached design capacity and expected levels of metallurgical performance. In May 1996, a decision was made to double the capacity of the concentrator by the addition of a second line of equipment. The expanded facilities were commissioned in October 1997, less than 18 months after the decision to proceed, and well within the budget. The original concentrator facilities were replicated or duplicated as much as possible, however, a number of important equipment changes were made to take advantage of industry developments since the original concentrator was designed. These included the use of Eimco 120 m3 (4,200 ft3) cells for rougher and scavenger flotation and the installation of a Svedala VTM-800Vertimill for regrinding. This paper describes the rationale behind these changes and explores the reasons for the success of the project.

Jan 1, 1999

This discussion of the paper of Chester W. Washburne should have been printed following the remarks of H. A. Wheeler, in Bulletin No. 100, April, 1915, pp. 835 and 836, but was inadvertently omitted. ROSWELL H. JOHNSON:-There is one reason why the hydrostatic interpretation of gas pressure is not wholly acceptable. As we go clown in the sands we seem to get excesses of gas. Particularly in this field it becomes excessive in quantity relative to the amount of water in the sand. If this holds in other fields as well it must mean that there has been an ascension of water, because these sedimentaries when laid down, were filled with connate water. If we do get an ascension of connate water, produced by some such phenomena as its expansion by heat or by the formation of new gas by pressure upon organic materials at great depth, we can hardly expect the pressure to be controlled merely hydrostatically. * In reply to Mr. Wheeler's inquiry as to gas wells with pressure higher than hydrostatic pressure, I would cite the original wells given by Orton on which he based the hydrostatic theory. He used in his calculation a head of 600 ft. above tide, assuming the outcrop of the Manitoulin Islands to be in Lake Superior, whereas the Trenton does not outcrop at Lake Superior. The Manitoulin Islands are in Lake Huron, the level of which is 580 ft. above tide. No allowance is made for the lower density of the fresher water near the outcrop, the weight taken for the whole column being the water of high density found at the wells.

Jan 5, 1915

By F. V. Antonio, R. S. Pizarro

Masbate Gold Mines, dormant since WWI I, are now back in operation. The ore treatment plant incorporates carbon-in-pulp processing, utilized because of the ready availability of coconut shell charcoal in the Philippines and the high clay content of the ore. A detailed description of the plant, including the surprisingly fast and efficient alcohol stripping facility is presented. Operating data for the plant is provided together with an interesting performance evaluation of mechanical versus air- lift agitated leach tanks.

Jan 1, 1981

By Henry M. Howe

PART I. § 1. Introduction. After giving certain definitions, this paper gives the reasons which led to Roozeboom's form of the diagram of the freezing-point curves and general equilibrium of the iron-carbon compounds, steel and cast-iron ; and then those which led to replacing it with the present or double diagram, in which graphite is at all temperatures held to be the more stable and cementite the less stable (metastable) form of carbon. Next in § 10 the evidence supporting this greater stability of graphite is examined, then in § 17 that which seems to oppose it, and in § 22 a summary of the evidence is presented. The second part of the paper considers the topography of the graphite-iron diagram, rejecting summarily the solubility-lines based on the data of Charpy and Grenet and of Mannes-mann, on the ground that the data even on their face do not really point toward these lines, and that they are wholly incompetent to determine any solubility-lines whatsoever, because they report together with the dissolved carbon also an indeterminate quantity of cement-carbon, and because even such carbon as is actually dissolved, only in part represents the solubility of graphite, and in another and indeterminate part represents the solubility of cementite, or at least of carbon in presence of cementite as distinguished from graphite. It might be thought that graphite is but slightly soluble in iron, because of the absence of any suggestions of eutectoid graphite, corresponding to the eutectoid cementite of pearlite in very many cases in which the cast-iron seems to consist of ferrite and massive graphite only, and because of the micrographs of Goerens and Gutowsky. In these the primary austenite of cast-iron quenched but little below the eutectic freezing-

Jan 7, 1908