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By Charles Will Wright

I. INTRODUCTION. THE application of the camera as an adjunct to topographic mapping began practically with its invention, and it has been employed with varying success since that time. With the exception of the camera to be described, the plate-camera has been universally used in this work, thus giving a projection of the area photographed on a flat surface. From such projections or photographs, by the rules of geometry and of perspective, points defining topographic features and seen from at least two camera-stations may be projected upon a ground-plane-the map.1 In 1904 I employed the plate-camera for this purpose in Alaska, but found that the labor necessary to plot the maps, even in a general way, was long and tedious. In 1905 a small Eastman panoramic camera was fitted with spirit-levels, a sightalidade and a transparent scale, introduced inside the camera to register the degree-points in the sky-line of the film-negative; also, arrows to indicate the horizon-line. This was, on the whole, successful; but the details in the topography were not brought out in the views with sufficient clearness, and the photographs were too small. These difficulties were overcome by obtaining a larger and more carefully constructed instrument, which was satisfactorily employed in the field during the year 1906. A panoramic view is made up of an integral number of perspective views upon flat surfaces, and logically is the most ac-

Jan 1, 1908

By Luis A. Tondo

The Paracatu Expansion Project III in Brazil was implemented between 2006 and 2008 to increase the existing capacity from 20 to 61 Million tons per year of gold ore treatment. This expansion led the Brazilian subsidiary of the Canadian Kinross Gold Corporation to become the single largest gold producer in Brazil and the largest single gold concentrator in the world, with a nominal capacity to treat around 167,000 tons per day of ore. This paper describes the Project Development areas for the Paracatu Expansion, using the approach proposed by the Project Management Institute (PMI) and the methodology included in the PMBOK (Project Management Book of Knowledge). The author has more than 20 years of experience in the gold mining industry, having worked as a plant metallurgist, mill superintendent and development manager for RPM until he took the position as the Project Manager of the Paracatu Expansion III in 2005. Luis Tondo has a BSc in Mining Engineering from UFRGS-Brazil, an MScEng from the University of Queensland - Australia and an MBA degree from FDC-Brazil. Luis is currently based in Santiago-Chile, acting as the Project Director for developing projects in Latin America for the Kinross Gold Corporation.

May 1, 2009

By Bernard MacDonald

Introduction. OF the treatment of the slime-pulp of gold- and silver-ores by cyanidation, agitation is an essential part. When prepared for treatment, this pulp, consisting of ore reduced to such fineness that approximately 80 per cent. of it will pass through a 200-mesh screen, is mixed with a certain proportion of water, carrying in solution the quantity of cyanide (KCN) and other chemicals required. The water-constituent of the pulp thus prepared usually ranges from 1 to 2 parts by weight to 1 of the dry ore. Thus constituted', the pulp is charged into treatment-tanks, the shape and capacity of which vary, according to the quantity of pulp to be treated daily and the method of agitation to be employed. Tanks have no other function in a cyanide-plant than that of being economical and convenient containers or receptacles for holding the pulp, solution, or water used in the operations. It is by agitation that the solids in the pulp charged into the tanks are kept in suspension in, and mixed with, the solution in the proper proportions required for the treatment. If the proper mixture of solution to solids be determined to be 2 to 1 by weight (which is, approximately, 5 to 1 by volume), this proportion should be maintained in every part of the charge ; -that is, each solid particle of the pulp, whether it be of 180- or 400-mesh size, should, be surrounded by five times its own volume of solution throughout the whole period of treatment. The reason is, that the amount of chemicals ascertained to be necessary for dissolving the gold and silver contained in the solids, is held in uniform solution in the water-constituent of the pulp, and, therefore, the determined proportions of solution and solids must be maintained at all times during treat-

Apr 1, 1912

By Cripps-Clark CJ

Sulphur partition between metal and slag has been examined on a cast-by-cast basis for BTIP furnaces. Partition values. were calculated from thermodynamic equilibrium data together with oxygen activities computed from the manganese partition. The S-C interaction coefficient, esc , was treated as an adjust- able parameter and the agreement between calculated and measured S partition values optimized. In the case of furnaces operating with low viscosity slags this procedure led to estimates of esc in close agreement with previously measured values. The same analysis applied to daily average data for several Kawasaki Steel furnaces led to the same esti- mates of e c s , indicating a similar approach to equilibrium. Silicon partition between metal and slag has been examined on a time average basis and found to be far removed from thermodynamic equilibrium for most Australian furnaces. A study of Japanese furnaces of comparable size reveals a temperature dependence of Si parti- tion which appears to be close to equilibrium. Australian furnaces approach this behaviour only when operating with low viscosity slags. A preliminary examination of the effects of burdening with TiO 2 on the silicon partition is also reported.

Jan 1, 1980

By M. Lahtinen, P. Latostenmaa, I. Kojo, E. Peuraniemi, M. Lindgren, S. Jyrkönen, M. Jåfs

The year 2019 marks the 70th anniversary of Flash Smelting. The technology was operated on industrial scale for the first time at the Outokumpu Harjavalta copper smelter in Finland in 1949. Since then Flash Smelting technology, now owned and developed by Outotec Oyj and the first plant, now owned by Boliden Harjavalta Oy, have been evolving throughout history by optimizing the process for various feeds and raw-materials, as well as through developing the equipment and operating practices. Even though sustainability was not a popular theme during the first days of Flash Smelting, it has still been the key principle in guiding the development. This is well proven by the wide adoption of Flash Smelting for the processing of copper and nickel concentrates, mostly due to its ability to fulfil the economic and resource efficiency criteria demanded by its operators. This paper describes the history and improvements of the Outotec® Flash Smelting process by looking into the early days of operation and how the development of the process and equipment has taken place over time as a joint effort between the technology provider and the users of the technology. INTRODUCTION In the 1940s, Outokumpu Oy refined the concentrate produced in the Outokumpu mine into metallic copper initially in Imatra, and later from 1945 to 1949 in Harjavalta, based on the most modern electrical melting process of the world at that time. After the war, Finland lost a significant part of its hydropower production, and due to the increasing use of electricity, the availability of electricity weakened, and the price rose. To maintain Outokumpu's profitability, it was forced to look for a melting solution that was not based on electricity.

Jan 1, 2019

By K. Collett

Elandsrand started shotcreting back in 1991. This paper will share the experiences of the mine by looking into the past, the present situation and the way Elandsrand plans to approach the future. It looks at the application of drycrete and discusses the factors that led to the introduction of wet fibre reinforced shotcrete. The logistical constraints of getting shotcrete material underground will be solved by the development of an underground batch plant, using run of mine waste rock as an aggregate.

Jan 1, 1998

The first hydraulic roof supports were installed underground in 1950s and ever since that time engineering developments have improved the supports in many different ways. However. advances in three main areas, the roof support mechanical design, hydraulic engineering and electronics have ultimately led to the point where, 35 years after that first installation. automation has been achieved and is now commonplace.The history of roof support automation has involved the continual integration of high technology engineering. Thera ate further possibilities for the future which combine to give some idea of the likelihood of there ultimately being a completely manless face.

Jan 1, 1991

By C. H. Burgess

ON June 5, 1947, Secretary of State George C. Marshall in a speech at Harvard University outlined a plan for the economic recovery of Europe. The plan contemplated that the United States should provide assistance which would enable the European nations better to help themselves and to help each other to reconstitute from their war-torn lands conditions which would make possible decent standards of living. The Foreign Assistance Act of 1948 was passed in April of that year, and established the Eco-

Jan 10, 1950

By G J. Corbett, T M. Leach

Although hosted within an Ordovician magmatic arc, the Peak Hill high sulphidation system displays features typical of youngerPacific Rim high sulphidation epithermal gold deposits. Regional NW trending transfer structures are inferred to localise the magmatic source at their intersection of the NS trending arc. Fluids have migrated from the magmatic source along NW structures and thence exploited permeable horizons, which have become silicified. Alteration displays typical zonation from silicification through assemblages characterised by alunite, pyrophyllite and kaolinite and is followed by breccia/fracture controlled sulphide and gold deposition. Sinistral rotation on the NS arc has dilated NW trending fractures to produce the WNW to EW dilational fractures which host the higher grade ore. Mineral assemblages are typical of formation distal to the magmatic source in an epithermal environment. The combination of alteration and mineralisation zonation with structure provide fluid vectors which target a magmatic source to the SE of Peak Hill.

Jan 1, 1995

By John G. Payne

The Pebble deposit contains three contiguous zones. In the Pebble West zone, granodiorite stocks intrude gently warped volcanosedimentary rocks that had been intruded by diorite sills and two felsic intrusion breccias. In the Central zone, volcanosedimentary rocks are cut by diorite and granodiorite sills; the latter are genetically associated with the granodiorite stocks. In these zones, widespread potassic alteration consists of brown biotite and K-feldspar, with abundant quartz-carbonate-sulphide vein stockworks. Chalcopyrite/pyrite ratios range from 2/1 to 1/20. Diorite hosts the highest-grade mineralization, with much of it being disseminated. Patchy, later phyllic alteration is moderate and commonly depleted in copper. The Pebble East zone occupies a granodiorite stock and intruded host rocks below an eastwardly thickening wedge of barren Tertiary volcanic and sedimentary rocks up to 600 m thick. Brown biotite alteration and copper mineralization are strong, with chalcopyrite/pyrite ratios commonly over 1/1. The zone extends to a depth of at least 1200 m below surface; some drill holes bottomed in strong mineralization. Later, weak to moderate sericitic alteration removed some chalcopyrite and locally remobilized gold. The Pebble deposit has a Measured/Indicated resource of 3 billion tonnes grading 0.28% Cu, 0.32 g/t Au and 0.015% Mo (= 0.5% copper-equivalent) and an Inferred resource of 1.13 billion tonnes grading 0.30 g/t Au, 0.27% Cu and 0.015% Mo (0.55% copper-equivalent). The Pebble East zone has an Inferred resource of 2.13 billion tonnes grading 0.55% Cu, 0.34 g/t Au, and 0.037% Mo (0.97% copper-equivalent). The Pebble East zone is open to the east and to a lesser extent to the north, south, and to depth.

May 1, 2006

By M. J. Gregory

The Pebble Cu-Au-Mo deposit in southwest Alaska is one of the world's largest porphyry deposits. The western part of the deposit was discovered by Cominco America in 1987, who sold the project to Northern Dynasty Minerals Ltd., in 2001. Northern Dynasty discovered the high-grade eastern part of the deposit in 2004 and went into a 50:50 partnership with Anglo American PLC in 2007, forming the Pebble Limited Partnership (Lang et al., 2008). The Pebble Limited Partnership has continued to delineate the deposit through diamond drilling with the most recent resource estimate released in February 2010 (Pebble Limited Partnership, 2010). The Pebble deposit mineral resources comprise 5.94 billion tonnes of measured and indicated resources grading 0.78% Cu EQ, containing 55 billion pounds of copper, 67 million ounces of gold and 3.3 billion pounds of molybdenum. Also delineated are 4.84 billion tonnes of inferred mineral resources grading 0.53% Cu EQ, containing 25.6 billion pounds of copper, 40.4 million ounces of gold and 2.3 billion pounds of molybdenum (Pebble Limited Partnership, 2010). Resources are calculated using a 0.3% Cu EQ cutoff. GEOLOGY AND MINERALIZATION Deposit Geology The Pebble deposit is located in the Kahiltna terrane, between terminal strands of the north-east-striking Lake Clarke strike-slip fault. This fault represents an accretionary boundary and separates the Kahiltna terrane to the north-west from the Peninsular terrane to the south-east (Lang et al., 2008). The Pebble deposit represents a large magmatic-hydrothermal system centered on a group of 90 million year old porphyritic hornblende granodiorite intrusions. An east-west cross section through the southern part of the deposit (Figure 1A) shows the typical relationships between the various rock units which host sulfide mineralization. Sub-parallel ~96 million year old granodiorite and diorite sills were intruded into siltstones of the Jura-Cretaceous Kahiltna flysch. In the west, these sills were cut by a ~96 million year old alkalic intrusive complex composed of porphyritic monzonites and monzodiorites and related intrusion breccias (Bouley et al, 1995). The mineralized 90 million year old hornblende granodiorite intrusions cut all rock types and comprise four small stocks in the western part of the deposit and a larger pluton in the eastern part of the deposit. Recent deep drilling indicates that these intrusions coalesce at depth. The strongest porphyry-style mineralization is centered on the eastern granodiorite pluton and extends into the surrounding rock units (Figure 1A). The western half of the deposit crops out at surface, whereas the eastern side is un-conformably overlain by a cover sequence of Late Cretaceous to Eocene sedimentary and volcanic strata. The deposit was tilted 20º to the east during the Eocene.

Jan 1, 2012

By C. Vanvoren

"Since 1975, the Aluminium Pechiney Research Centre at Saint-Jean-de-Maurienne (LRF) has been concentrating its efforts on designing, testing and perfecting the Aluminium Pechiney point-fed prebaked reduction cell.In 1979, the AP18 cell (180 kA) was industrially launched with the construction and start-up of the F line in Saint-Jean. The following generation, the AP30 (300 kA), with prototypes started in 1981, was launched in 1986 on the Saint-Jean G line. Along with cell design, efficient process control systems were developed to pilot alumina feeding and bath composition. Together, these pots are currently producing 4.6 Mt of aluminum, i.e., 18% of the world’s overall yearly production.In 1989, the research centre faced a new challenge: to push the limits for the size of a reduction cell to further improve the profitability of Greenfield projects. This new generation development was also the opportunity for a significant redesign of the Aluminium Pechiney electrolysis information system.With a track record of ten years of semiindustrial operation with three prototypes, the AP50 technology is now ready for industrial implementation and enables a significant breakthrough to be made in terms of return on investment of a Greenfield smelter."

Jan 1, 2002

By John J. Stetler

The Companhia Vale do Rio Doce in Brazil operates one of the most extensive systems in the world for the mining, transportation, processing, pelletizing and shipping of high grade hematite iron ore and pellets. Current shipping of unbeneficiated, sized, high grade ore from its ports at Tubarão and Vitória is now at the rate of 17,500,000 metric tons annually. An increase in this annual rate is now under study. Using the technology and facilities of Lurgi (1) and Arthur G. McKee company CVRD undertook a program to process and pelletize two types of fines - "Blue Dust" and ?Itabira Fines?. Blue Dust is a high grade fine ore which was bypassed while mining the direct shipping ores and which, also, exists as a very large ore body called the Conceição Mine. Itabira Fines is a lower grade of fine ore which is comprised of in-situ fines and, also fines which are generated in sizing the direct shipping ores for a rigid specification market.

Jan 1, 1970

By H. P. Pew

THE Pembina oil field is in west-central Alberta, about 88 miles west-southwest of Edmonton. The field, about 35 miles long by T HE Pembina oil field is in west-central Alberta, about 88 miles west-southwest of Edmonton. The field, about 35 miles long by 85 miles wide, is the largest in Canada in areal extent, in the amount of oil in place and in the current producing rate. The discovery well was completed in the middle of 1953. The field has grown until its present area is 369,820 acres. There are 74 working interest owners in the field. Early in the producing history of the Pembina field a committee of operators was formed on a permanent basis. The Pembina Operators' Committee has established a permanent staff, which compiles and distributes pertinent field information on a regular basis to all participants. The Alberta Oil and Gas Conservation Board has dealt with field-wide problems primarily through this committee. Expansion of the field was rapid as shown by the number of wells completed -from 135

Jan 1, 1961

By H. Groeneveld, C. A. Connally, P. J. Hoenmans, W. L. Mason, John J. Justen

"A miscible displacement pilot, using a slug of LPG driven by separator gas, was conducted in the Cardium Reservoir of the Pembina Field. The injection pattern was a 10-acre, inverted, isolated five-spot. Upon completion of the LPG-gas phase, an .experiment was conducted using a slug of water followed by gas. Calculated performance of the pilot is compared with actual performance. Equations are developed to cakulate the distribution of LPG into zones of varying permeability, to estimate the progress of the flood at different times in the various zones, and to estimate gas rates after breakthrough. The analysis indicates that permeability stratification was a dominant factor in con-trolling oil recovery and that oil was completely displaced from the swept pore volume. The results of the pilot indicated that miscible flooding is a practical means of pressure maintenance in this reservoir. The total recovery from the pilot area was good in spite of the early breakthrough of LPG. The effects of stratification were reduced by injecting a slug of water into the partially swept reservoir."

Jan 1, 1960

By K. P. Wang

Mining and metallurgy have had a long history in China, and resources there have always been considered promising. Under the People's Republic of China (PRC), a remarkable industrial renaissance is underway that should further gain momentum in the years ahead. Rapid development of minerals have not only brought the PRC prominence in industrialization, but also in world affairs. Chinese mineral developments, especially petroleum, have been increasingly in the news. Oil and gas may have great potential, but a very large coal industry is already in existence. The steel industry ranks fifth or sixth in the world. The PRC is also prominent in fertilizer, cement, and salt production. The export metals are well known. Also, the country is buying heavily in nonferrous base metals. The need to know and the intense interest in the subject have prompted this study. The world significance of Chinese minerals is pointed out. The history of growth and PRC's mineral supply position are reviewed. Evaluations are made of policy considerations and regional and technical factors affecting mineral development. PRC's mineral trade and efforts to obtain equipment, supplies, and know-how are assessed. Specific reviews are made of major mineral sectors, including coal and power, oil and gas, iron and steel, nonferrous metals, industrial minerals, and fertilizers and chemicals. The overall outlook is summarized.

Jan 1, 1975

Jan 1, 2009

By A. B. Fox, R. P. Thackray, K. C. Mills

The role of mould fluxes in continuous casting is reviewed. The main functions of the flux are described and the importance of the flux in providing lubrication and the right level of heat transfer between the shell and the mould is described. The major problems of longitudinal, transverse and star cracking, gas and slag entrapment and deep oscillation marks in the steel product and ?sticker breakouts? are analysed. The important physical properties of the flux in combating these various problems are identified. Physical property data for the fluxes are given.

Jan 1, 2004

By W. T. Walter

High-G centrifuges from five preparation plants were sampled to determine and quantify the various operating factors affecting performance. The operating factors that were considered include feed rate and percent solids, size of feed material, screen-basket type, hardness of coal and age of the flights. The performance parameters that were measured include product surface moisture, recovery and degradation of the coal. Regression equations with good significance levels were developed.

Jan 1, 1982

By B. R. Bowerman, W. J. Thoburn, M. J. Humphris

"Nickel granules are produced for carbonylation by pouring a molten stream into a path of high pressure water. Granules and water are separated in dewatering bins. The overflow, which contains up to 0.1 weight percent solids, was initially cooled and recycled to the granulating step. However, the rate of buildup of these solids in the handling system was intolerable. A lamella thickener was installed to solve the problem by removing solids from the dewatering bin overflow. Its description, application and performance to date are discussed.The lamella thickener treats a slurry containing about 0.1% solids of which about 30 weight percent is less than 325 mesh. It recovers 80 to 90 percent of the input solids in an underflow slurry containing 90 weight percent solids. Since its installation the frequency of cleanout of the recycle water handling system has dropped from about once per month to about once or twice per-year."

Jan 1, 1977