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By W. H. Hoffman

The writer does not claim a right to discnss this subject as a furnace-man or user of iron-ore in this new form. His efforts have been confined to mining, preparing, and separating the magnetic ore from the gangue. Two years' experience in experimenting and another two years in producing concentrates on a commercial scale, have led me to believe that the new trade of making concentrates must be well learned in all of its details. If there have been any partial failures in this most useful branch of the iron business, the failures have been caused chiefly by inexperience or lack of patience. Although I have, within the past five years, constructed machinery

Jan 1, 1892

By F. H. Newell

Measurements of the amount of water flowing in many of the larger rivers of the west have been made by the United States Geological Survey, and by this means the daily discharges of these rivers have been computed for a period of over two years. These measurements have been confined mainly to that part of the country commonly known as the arid region, where the rainfall is insufficient for the needs of plants most useful to man, and the supply of water, not only for agriculture, but also for mining and all other purposes, falls below the demands made upon it. In such localities flowing water has a great value, for without it many industries are impossible. Experience has shown that in the western part of the United States, over an area a little less than two-fifths of the whole extent of the country, there are great bodies of fertile land enjoying a genial climate, and in every way adapted to the support of a large population, except in the one particular of water-supply. By utilizing the water available, portions of this rich land can be rendered valnable. In other words, the laud-values rest directly upon the prospects of a continuous artificial water-supply. The same is true of many mineral lands, which require for hydraulic mining, or for the supply of concentrating-works, stanip-mills, etc., a certain water-supply, and are impaired in value if this supply is inadequate or irregular. The pressure of this need upon the mining industry is not so widespread, or in the first instance so severe as upon agriculture; but as different regions become more thickly settled, and the two industries compete for a water-supply not sufficient for both, it, is probable that the miner will suffer. But he can snspend operations with less inconvenience than the farmer. Agricuitural land, if the watersupply is not continuous, becomes a desert; on the other hand, the profit of mining is greatly enhanced by the presence of agricultural

Jan 1, 1892

By T. A. Rickard

Among the names which won a world-wide fame during the golden age of the early fifties, Bendigo and Ballarat were to Australia, what the Yuba and Grass Valley were to California. The map of Victoria did not for a long time show the name of old Bendigo;* for this first and more distinctive name was replaced with the more English Sandhurst, just as the alluvial diggings gave place to quartz mining. Towards the close of last pear, steps were taken to give back the old name, as associated with the early days of rich alluvium, and more suggestive than the application taken secondhand from an English military academy. History. The first discovery of gold? in this district, was made in the autumn of 1851 ; but there has never been any certainty as to the day or the man. At that time the country around Bendigo Creek was a part of the Ravenswootl sheep-run, and its resemblance to the Forest Creek district (now Castlemaine), induced the first prospecting. It was late in November when the "rush" broke out; the shepherds left their flocks; the sylvan solitudes were disturbed by * The name of Bendigo is said to have been derived from a hut-keeper on the Ravenswood sheep-run, who on account of his fondness for " fisticuffs " was nicknamed Bendigo, after the prize-fighter of that name. It is not aboriginal, as is often supposed, but Spanish ; and equivalent to our Benedict. There must always be some confusion between the two names of Sandhurst and Bendigo; the town, and with it the gold-field, having been three tinies named. Several other old familiar names have been likewise unfortunately replaced by second-hand English ones; so that an old digger talks of Forest Creek when he means the modern Castlemaine, Mt. Ida for Heathcote, Growler's Creek for Bright, etc. I shall use the names Sandhurst and Bendigo interchangeably. The first discovery of gold in Australia, was made by E. H.Hargraves, February 12, 1851, near Bathurst in New South Wales. In August of the same year the discovery at Buninyong, near Ballarat, inaugurated the first of a series of rushes to the Victoria gold-fields.

Jan 1, 1892

By Geo. H. Eldridge

This sketch of the Florence oil-field, presented to the Institute by permission of the Director of the U. S. Geological Survey, is accompanied with a map, Fig. 1, the topography of which has been taken from a field-manuscript of the Survey. The scale of the map and

Jan 1, 1892

By John Birkinbine

Four meetings of the Institute have been held in the anthracite coal-fields of Pennsylvania, and excursioris into the district, in connection with meetings elsewhere, have familiarized our members with

Jan 1, 1892

[Note.—The paper of Mr. Hoffman on " Practical Results in the Magnetic Concentration of Iron-Ore " (page 602); that of Mr. Langdon on "The Use of Magnetic Concentrates in the Port Henry Blast-Furnaaces" (page 599); and those of Mr. Landis on "The Determination of Iron in the Tails from Magnetic Concentration " (page 609) and "Note on Sampling Iron-Ore" (page 611), were all prepared as contributions to this discussion.] The papers of Mr. Langdon and Mr. Hoffman were presented. W. H. Hoffman, Croton Mines, N. Y.: I will add a few remarks, by way of answer to inquiries for further details. The Croton Mines are particularly well located for cheap mining. The ore-bed is very large, and so lies in relation to the railway tracks of the Harlem and other railroads that a very large proportion of our mining for several years to come can be done above these tracks. The concentrating-mill is now 400 feet from where we are working in the quarry. In blasting we never remove less than 2500 tons at a blast,

Jan 1, 1892

By Karl Eilers

This process, invented by Messrs. Hanisch and Schroder, of Rosdzin, was patented in 1883. It has attracted considerable attention in Germany, as a very neat and simple method of extracting sulphurous acid from the gases produced by roasting, and of condensing this acid so as to obtain it in the very compact anhydrous liquid form. The special importance which such a process may have at this time in the United States is suggested by the growing inconvenience, amounting to distress, experienced in such localities as Butte, Mont., where the sulphurous gases from large roast-plants have proved not only fatal to vegetation but injurious to human health. It is reported that the authorities of Butte are earnestly considering the enterprise of removing, if practicable, the dense and suffocating cloud which now hangs over that city, and of which sulphurous acid undoubtedly forms the greater and most oppressive, if not the most poisonous, part. May it not be that the solution of this problem is furnished by a

Jan 1, 1892

By Alfred E. Hunt

Tars paper is suggested by the appointment on the part of the American Societies of Mechanical and of Civil Engineers of committees upon the subjects of " Standard Tests and Methods of Testing," and " Uniform Methods of Tests of Material used in Metallic Structures," respectively, and by a study of the report of one of these committees, and other papers. Moreover, the writer has had frequent occasion to hear the complahts of tnanufacturers who furnish structural material subject to specifications, that in the tests prescribed, the number of tests required, and the methods of making

Jan 1, 1892

By Rufus J. Foster

During the discussion on the Preparation and Utilization of Sniall Sizes of Anthracite (page 613 of present volume), several inquiries were made concerning the use of the McClave grate, which was mentioned by Mr. Coxe as having proved satisfactory in the generation of steam at his collieries, and also at a large number of industrial estal)lishments in Scranton and elsewhere. For a more satisfactory repIy to such inquiries than could be furnished in the oral discussion, I have prepared the following paper to be included in the published proceedings. And, as the use of the fuel under consideration necessarily requires the employment of a blower to change the fire, from a condition giving an incandescent radiant heat only to one giving a hot gaseoua flame as well, I shall add a description of the McClave Argand blower and its method of action. The grate and blower combined form a complete and effective system fcr burning small fuels, such as anthracite culm, birdseye, buckwheat, bituminous slack, etc., in boiler and other furnaces; while the grate alone is now extensively used with the larger sizes of hard and soft coal in furnaces where blast is riot required. Fig. 1 is a view of the RlcClave grate as built in two sections. It is constructed on the principle best approved by practice to prevent warping and burning out; that is, it presents no long lines of

Jan 1, 1892

By Kerry Spickelmier

The only nickel smelter and the only active nickel mine in the United States is Glenbrook Nickel Co., a joint venture (50% each) of Cominco Resources International Ltd. and Cominco Ltd. In 1989, with the nickel price riding high between $2.30 and $2.70/kg ($5 and $6/lb), Glenbrook seized the opportunity to purchase and recommission a southwestern Oregon ferronickel smelter and the adjacent nickel-ore mine. This Douglas County site is only about 97 km (60 miles) due east of the Pacific Ocean, and California's border lies a similar distance to the south. Hanna Mining Co. had closed the operation in 1987. And the following year, the equipment had been largely stripped for salvage value. From November 1990 through August 1992, the mine supplied an average 5 kt/d (5500 wet stpd) of ore. Currently, with import ore supplying 40% of the smelter feed, the mine's daily tonnage averages 4.2 kt (4600 wet st). From November 1990 through August 1993, the mine has delivered 2.1 Mt (2.3 million st) of ore grading 1.22% nickel with an average moisture content of 26%. Buffaloed nickel? A nickel is not worth what it was in 1989 and neither is ferronickel, with recent prices hovering around $1.13/kg ($2.50/lb). To survive, Glenbrook has focused on increasing smelter production to lower its operating costs. And this strategy has triggered several bold moves: • a new, $30 million, port facility and • a 10-year importation contract for ore from New Caledonia, an island approximately 1000 km (625 miles) east of Australia. For a Glenbrook update, a May 25, 1993 visit was made to the company's Oregon operations - the mine and smelter near Riddle plus its new Coos Bay port facility. Unfortunately, as the rain came down that day, so did news of another temporary shutdown. The previous suspension had lasted from Dec. 20, 1992 until Feb. 22, 1993. Barely three months back to work on a wet May afternoon, more than 250 of Glenbrook's approximately 300 employees contemplated yet another shutdown, effective July 31, 1993.

Jan 1, 1993

By A Price, D Okle, K Brooks

The operation of flotation plants has been improved over the years by use of fundamentally based design techniques, a better understanding of reagent chemistry, online metal analysis and the use of digital control systems. However, optimal operation of flotation banks is not consistently achieved using manual operation. The reason for this is that the system is a highly interacting one, with changes in air addition, cell interface level and reagent dosages all being available, without it necessarily being clear as to which change should be made for a particular situation.This situation is made more complex by the fact that the feed to a flotation bank can vary in flowrate, composition and density over a fairly short period of time. It is not possible for a human operator to reject these disturbances, given the extent of the operation that is typically being monitored.Model predictive control (MPC) is a control and optimisation technique, developed in the oil refining industry, that aims to manage just such interacting multiple input multiple output (MIMO) systems. This technology makes use of linear dynamic models of the plant, that are experimentally derived. These models are then used in a receding horizon strategy to determine an optimal trajectory of the inputs to the system.MPC has been applied to four areas of the lead zinc flotation unit at Mount Isa mines. A total of 31 cells are being controlled by the system, which varies air to the cells, levels and reagent addition on a minute-by minute basis. The MPC controls concentrate and tail grades, reagent dosages, as well as recoveries to ranges set by the plant metallurgists.The development of the MPCs is discussed, together with the benefits realised. The key factors in insuring an ongoing return on investment are described.CITATION:Price, A, Okle, D and Brooks, K, 2018. Glencore Mount Isa lead zinc flotation circuit – experiences from the implementation of model predictive control, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 101–110 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By Y. Shiraishi, Y. Sakurai

A new method, the gliding cylinder method, was proposed as a wide range viscometer for the measurements of molten salts, slags, and glasses. The method consists of two coaxial cylinders, cylindrical bob and a vessel containing a liquid sample. There is a narrow gap between bob and vessel. When the vessel moves against the bob, the generated force on the bob consists of three types of resistance: (1) Stokes’s resistance on the bob, (2) a capillary flow resistance though an annular gap between vessel and bob, and (3) lubricating resistance in a gap. The last two can be calculated on a theoretical basis but the first cannot be estimated by a simple calculation since a wall effect did not calculate easily. However, it can be assumed that the generated force depends on both the viscosity of a liquid and velocity of the vessel. Thus, the relation between viscosity and a force at desired velocity of the vessel was measured using several standard reference materials including glycerol aqueous solutions and standard reference oils. The results depended on the magnitude of the gap between the bob and the vessel. For the wider gap, it was shown that the viscosity is a linear function of a gradient of force with respect to a vessel velocity. In contrast, if the gap is small, the viscosity depends on the gradient (of force with respect to velocity). This implies that the non-linear phenomena would occur in Stokes resistance. Though detailed analysis is in a further investigation, a calibration method can be applied to determine the viscosity by this method, because good correlation was obtained among these quantities. Viscosity of molten salts, such as NaNO3and ZnCl2was measured by this method as high temperature demonstration. Keywords: viscometer, viscosity, sphere pull-up method, fused salts, molten slags, glass melts

Jan 1, 2004

By Jim Robertson

Summary of Presentation ??What is the GARD Guide ??The Need for a GARD Guide ??Mining Industry?s Commitment to Solving ARD Problems ??The Ultimate Solution ?You ??The GARD Guide ?Scope ??The GARD Guide ?Structure ??Wiki Demonstration

May 1, 2009

A series of fault slip seismic events have occurred at Garson mine. The events have occurred during development advancement exposing faults, after the extraction of single stopes due to mining induced stress change, and due to time effects after delays of many days during which no mining had been conducted. This paper discusses the study completed consisting of a global or holistic approach aimed at mitigating some of the risks associated with the structurally controlled rockbursts at Garson. Background Garson mine is located in the south east area of the Sudbury Basin (Ontario, Canada). Mining occurs in two main ore bodies (the #1 Shear and the #4 Shear) which are copper-nickel-sulphide and occur within shear zones that (as well as the ore bodies) strike approximately east-west and dip steeply south. From the north (footwall), lithologies progress (Figure 1a) from norite (NR), to greenstone (GS), and finally to meta-sediment (MTSD). A generally WNW-ESE striking, bifurcated sub-vertical dyke of olivine diabase (OLDI) cuts the series. The current active mining block at Garson is between 4700L and 5100L (levels denote depth in feet below surface).

May 1, 2009

By R. F. Baxter, C. M. Read, R. I. McCulloch

"Globalization of the aluminium industry continues to increase the pace of change and the intensity of competition, while simultaneously, society demands better products, cleaner technologies and sustainable industries. Bechtel, a global engineering, construction and project management company, is not immune to either the opportunities or the challenges created by globalization. However, and not withstanding the challenges, for aluminium industry ""players"" with a true global perspective, globalization presents very real opportunities that may be leveraged to deliver value creating goods and services. The following paper will focus on the exploitation of one of the opportunities created by globalization in the Knowledge Management domain - the application of high level tools and methodologies to improve global delivery of greenfield and brownfield aluminium smelter construction projects. Specific examples will be presented of value driven solutions that were delivered at the early stages of project engineering."

Jan 1, 2006

In recent years new instrumentation and digital technology have Wrote possible a new facet of goo-physics: broadband seismology. From digitally record-ing networks and arrays. broadband scistnograrns of body waves that are flat to displacement and veloc-ity in at least the frequency range from 0.01 to 5.0 liz can now be routinely obtained for most carthquakes of magnitude greater than about 5.5. In contrast to data from conventional narrowband seismographs, broad-band body waves have sufficient spectral information to nvest,igate the many frequency-dependent eflects that may arise from source finiteness and from wave prop-agat ion phenomenon. Besides the usual parameters of depth. moment and focal mechanism, broadband data have sufficient spectral information to provide estimates of radiated energy, associated stresses and the frequency dependence of source parameters. Moreover. teleseis-mically recorded broadband data and near-field strong motion accelerograms overlap in the frequency band be-tween about 0.1-2.0 Hz. Thus. v it h broadband data it is possible to connect far field and near field data in order to make estimates of acceleration for almost any seismically active region of the circum-Pacific.

Jan 1, 1990

The last time Mining Engineering presented an issue with a special focus on Canadian Mining (ME, August 2008 pp. 28 to 40) things were going well. A feature story took a look at Xstrata?s Nickel Rim South Mine in Sudbury and the booming Canadian oil sands were discussed at length. Potash prices were soaring, large diamonds were being found and British Columbia was launching plans to find more workers. How things have changed in six short months. What began as a mortgage crisis grew into a credit crisis, then mutated into a financial crisis, that has taken its toll on the value of bonds, loans, stocks, real estate and commodities. Miners that were flying high on unprecedented commodity prices six months ago have begun scaling back with delays, shut downs and layoffs as they struggle to survive this most recent economic downturn.

Jan 1, 2009

By Constantin D. Pitis

?Demand-side measure" means a rate, measure, action or program undertaken to conserve energy or promote energy efficiency?? (BCUC, 1996) In actual economical environment, business sustainability requires high-efficiency technological processes. That is why the efficiency concept has to be present at all levels of industrial activities. Nowadays, some purchasing decisions are still driven predominately by the purchase price, in spite of the evidence that such price represents up to 5 % to 7 % of the total costs of ownership with full consequences of energy efficiency and the impact on total ownership costs. The paper presents essentials of converter types and basics of the Global Efficiency (GEff) Concept that has been promoted over the last few years in South African industries (Pitis et al., 2006/7). GEff concept is proven as a useful tool used on price-efficiency decisions. Theoretical and technical aspects of this concept were substantiated with case studies. First part presented in this paper will describe how GEff concept was used on price ? efficiency decisions when single input or direct converters and systems (considered as low value equipments) have been replaced. Besides the impact of energy savings and new innovative developments, the paper suggests general other benefits of: ? Technical and economical performance improvements and competitiveness of mining corporations to international standards; ? Defusing incipient energy crisis in the sector; ? Improving environmental conditions; ? Creating new job opportunities in mining sector. Proposed concept in this paper could be further developed as models of improving companies? corporate energy policies.

May 1, 2010

A review of the most widely used global extraction sequences in sublevel is undertaken. The review includes techniques used to extract massive as well as single or multiple steeply dipping tabular orebodies. The paper also deals with thick flat lying orebodies suitable for open stoping. Techniques used to minimise the effect of stress redistributions on a global scale are discussed for all the extraction sequences analysed.

Jan 1, 2003

By Kenneth Holmnerg

About 100 million terajoule is used annually worldwide to overcome friction and that is one fifth of all energy produced. The largest quantities of energy are used by industry (29%) and in transportation (27%). Based on our recent studies on energy use in passenger cars, trucks and buses, we concluded that it is possible to save as much as 17.5% of the energy use in road transports in the short term (5-9 years) by effective implementation of new tribological solutions. This equals to annual energy savings of 11.6 exajoules, fuel savings of 330 billion liters and reduction in CO2 emission by 860 million tonnes. In a paper mill, 15-25% of the energy used is spent to overcome friction. The electrical energy used by a paper machine is distributed as 32% to overcome friction, 36% for the paper production and mass transportation, and 32% is other losses. In paper machines, 11% of the total energy used to overcome friction can be saved by the implementation of new tribological technologies. This would result in electrical energy savings worldwide of 130,000 terajoule, economic cost savings of 2 billion euros and CO2 emission reduction of 11 million tonnes annually. An overview of the total energy saving potential by improved tribology in transportation and industry is presented.

Jul 31, 2018