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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 W. H. Blauvelt

THat the problem of utilizing anthracite waste is worthy of the thought bestowed upon it, may be shown in few words. In the year 1889, for instance, 35,408,000 tons of coal were sent to market from the anthracite regions of Pennsylvania. According to the report of the State Geological Survey, the amount of coal thrown on the dumps as waste, varies, with circumstancett, from 44 to 60 per cent. of that shipped to market. The lower of these figures represents 16,579,000 tons of waste for that year, and it is obvious that if this, or any considerable portion of it, could have been saved, it would have constituted an important addition to the fuel-supply of the country. It is not surprising, therefore, that so much attention has been given to the utilization of this waste. Among the many lines of experiment pursued with this object in view, the conversion of the carbon of the culm into producer-gas seemg at first to promise the most satisfactory solution of the problem. It is well known that in foreign producer-plants almost all kinds of

Jan 1, 1892

By Axel Sahlin

Since the days of the infancy of metallurgical industries, slags of various kinds have been accumulating. Until a comparatively recent date hardly any employment had been found for these waste products, which have had, consequently, little or no value. An exception to this rule is the basic Bessemer slag, the value of which has become universally recognized. It is to-day one of the standard fertilizers of the world, and a price of from $15 to $20 a ton is considered reasoiable for the ground slag, which, especially in Germany, finds a ready market as fast as it is prepared. The slags from puddling and re-heating furnaces have only found vol. xx.—25

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 John V. Beall

The Glidden Co., a newcomer to the mining industry, will be putting on stream its Lakehurst mine and concentrator this spring. Ilmenite-bearing placer sands will be mined and concentrated in a spanking new combination gravity, magnetic and high-tension separation plant. Glidden, well known as a paint, chemical and food manufacturer, consumes titanium dioxide as pigment in its paint business. The commodity is produced at the company's Adrian D. Joyce Works in Baltimore from ilmenite purchased in India and Australia, The Lakehurst operation, handily located in Ocean County, N. J., will dampen any deficiencies in quantity or price which might occur from foreign suppliers. This objective is no overnight concoction of The Glidden Co., because the move at Lakehurst was preceded by an attempt to start up in Florida. That project was abandoned when it was found that the titanium dioxide values were largely in rutile-a mineral which does not lend itself readily to the digestion process of the Baltimore chemical plant.

Jan 1, 1962

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

The Pacific Rim and its environment involves a vast array of natural phenomena, and a vast array of situations which show the impact of man. Almost half the world's population of over five billion live in nations" which border the Pacific, but the concentration is focussed in the North. Great experiments are occurring in this region, the industrialization and energy development in- Japan and China, the growth of Indonesia, (now 168 million - soon 368 million; Brown and Jacobson, 1986), the enormous developments of agriculture and the metals resource base in Australia and China. At the same time, the Pacific Rim does not project images of hopelessness, the mood is upbeat. Over the past decade, incomes have increased substantially in most of the major countries of Pacific Rim (e.g. over the period 1980-86, + 58% in China, + 21% in Japan, + 34% in South Korea; Brown and Jacobson, 1986). In September, 1986, at the general assembly of the International Council of Scientific Unions (ICSU) in Bern, Switzerland, representatives of over 50 nations approved a new initiative, "The International Geosphere Biosphere Programme: A Study of Global Change". The focus of this new program is "To describe and understand the interactive physical , chemical , and biological processes that regulate the total Earth system, the unique environment that it provides for life, the changes that are occurring in this system, and the manner in which they are influenced by man. The IGBP will be a tightly-defined programme of research, directed at providing fundamental knowledge that will serve as a basis for assessing likely future changes on the Earth in the next 100 years" (ICSU, 1986). For the earth scientist, and all resource scientists, there is an emerging agenda; new priorities are appearing, new questions are being asked. The recent report of the World Resources Institute (1986) focusses on this emerging agenda. Topics which are at centre stage in this report include the following: The environment and human health Tropical deforestation The atmosphere as a shared resource and climates Soil-degradation Rural-urban migrations Food and agriculture The diversity of species-ecosystems Freshwater as a finite resource Coastal areas and resources

Jan 1, 1987

By Gary A. Campbell

This article is an analysis of world consumption of copper for the years 1976-1996. It is done to provide a comparison of what has happened over this time period with the trends of previous years in order to learn more about world copper consumption and to forecast world copper consumption trends into the new millennium. The analysis begins by documenting the geographic trends of consumption of copper for the years 1976-1996 by both region and key individual countries. Then, variables based on the intensity-of-use hypothesis and the intensity-of-use technique are selected and tested against the observed consumption behavior by using the correlation coefficient technique. The statistical results and their implications for the consumption of copper into the new millennium are discussed.

Jan 1, 1999

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

By Henrique Garcia Pereira

In a large scale mining project, the global feasibility study must take into account the interdependence of three sub systems: the geological subsystem, represented by the orebody model; the technological subsystem, consisting .of mining and ore dressing models; and the economic subsystem, including the selling price of final product, production costs and investments. In cases where the ore is heterogeneous, the interdependence between geological and technological subsystems may be assessed by a Data Analysis technique such as Correspondence Analysis (CA). This technique was applied by David and Dagbert (1975) on examples of data from geochemistry and geology. In the approach used in this paper, CA is used to create the basic framework for defining different types of ore. The final definitions of ore types take into account the mi¬ning method and the results of applying beneficiation processes to the ore.

Jan 1, 1982

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 W. C. J. van Rensburg

Exploration of unconventional mineral resources is stimulated by uncertainties about the cost and security of conventional resource sup- plies. Costs of the latter are likely to increase as a result of inflation, higher energy costs declining productivity, a lack of sufficient investment in politically volatile areas, or through cartel-like action. Exploration of unconventional resources is likely to be delayed by these same factors, insufficient research and development facilities, and a decline in capital formation. World economic growth is likely to be slow, so there will be more emphasis on material conservation. Therefore, the incentive to explore for unconventional resources may be reduced.

Jan 1, 1983

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

By TTE-Europe GmbH

A few years ago, the term Track & Trace for explosives was only known in Europe and Brazil at most; the introduction of this technology is experiencing an undreamt-of boom worldwide. More and more countries are enacting legislation to introduce Track & Trace of explosives and follow Europe and Brazil on this path. At present, the world's leading manufacturers are already using such solutions, are in the process of implementing them, or are in the planning process. However, based on the experience gained in Europe, there are outstanding challenges for all manufacturers. These are questions of compliance, logistics, distribution, and, of course, especially, the necessary adaptation of the production environment. However, this development involves considerable effort on the part of the manufacturers. New devices for marking the explosives and digitally recording the data are integrated into the production process. This should be done as cost-effectively as possible, without restricting production capacity and speed, and with as few process changes as possible. This paper uses real-life customer experiences examples to explain paths from project design to real implementation. Lessons learned from the experience of European explosives manufacturers are presented, missteps are described, and solutions are identified. Individual steps along this path are explained, and solutions are told to avoid pitfalls and bottlenecks. Finally, it refers to the risk analysis and concrete examples in implementing the planning into production. Methods of marking various explosives are shown, and the use of Track & Trace to solve logistics tasks in picking and shipping explosives, including the data exchange with ERP (Enterprise Resource Planning) systems.

Jan 26, 2026