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By D. H. Magoon

The zinc smelter of Cominco Ltd. at Trail, B.C. Is the largest In the western world. A total of 550.000 tonnes of concentrate are proceed at the smelter annually. Approximately 80% of the zinc concentrate is roasted and the remainder Is treated by aqueous oxidation preaaure leaching. The zinc concentrate roasting and sulphur dioxide gas processing plants have undergone many changes over the years. This paper describes the processes and equipment currently used for concentrate roasting, S02 gas cooling and cleaning, mercury removal, sulphuric acid production liquid S02 production, and tall gas S02 scrubbing. The recent Installation of an advanced process control system for the operation of these Integrated processes Is also described.

Jan 1, 1990

By Austin Gudmundsen

"The smoke nuisance, like many other undesirable and longstanding features in our present civilization, is still with us. On reviewing the situation we are astonished to find no authentic record of a major smoke-abatement campaign that has succeeded in eliminating a smoke nuisance, in spite of the fact that the problem has been with us since the use of bituminous coal began. We might well ask ourselves where the trouble lies; is the problem impossible of solution? We can not blame the average citizen for harboring this thought as a conviction. He has been urged for so long but sees so little evidence of progress. He has repeatedly been assured by the scientist and the engineer in most convincing terms that smoke. is unnecessary, that it can be avoided; small wonder is it that he is beginning to distrust so-called authority on the subject.On the other hand, the scientist and engineer are entirely within their rights. We all know that even high-volatile coal can be and is now being burned with no visible smoke. We know that even small domestic heating furnaces, with favorable conditions and with proper care, can be fired by hand without producing much smoke. And we know that when such equipment is fitted with suitable stoking devices, little or no smoke results. What, then, is the answer?Perhaps we may learn something from a critical examination of a typical smoke-abatement problem. Probably one of the most enlightening campaigns that has been waged in the United States is that of Salt Lake City, Utah; therefore, the purpose of this paper is to discuss the important aspects of this particular case."

Apr 1, 1930

By Henry P. Cole

A series of studies are described that identify critical health and safety skills needed by underground coal miners for coping with mine emergencies. First aid and self-rescue and escape were selected as two broad performance domains that include many subordinate skills needed for preventing, recognizing, and coping with mine emergencies. The performance domains and their objectives were used to direct the development of simulation exercises that permit miners to experience mine emergencies in the safety of a training room. The exercises are based upon research with similar simulations for the training of flight crews and medical personnel in information gathering, judgment, and decision making skills. Exercise content is drawn from actual mine accident and disaster case studies. The exercises incorporate recent principles of cognitive psychology and instructional design. Initial studies in annual refresher training classes suggest the exercises are stimulating for miners and their instructors, easy to use and read, sufficiently complex and authentic to challenge experienced miners, and useful devices for both teaching and testing critical problem solving skills required for preventing and minimizing emergencies.

Jan 1, 1988

By James Ransford Dankwah

This work investigates the effect of waste plastics addition on the reduction of iron oxide by sawdust. Composite pellets of iron oxide containing sawdust (SD), high density polyethylene (HDPE) and blends of SD/HDPE were fired under argon in a horizontal tube furnace at temperatures between 1300 and 1500 °C. Reduced samples were weighed after 10 minutes of reduction and the extent of reduction was calculated from the measured oxygen contents of the compact. The results showed improved extent of reduction when SD was blended with HDPE. The highest extent of reduction was achieved at SD:HDPE ratio of 2:3.

Jan 1, 2014

By Hugo E. Camargo, Amanda S. Azman, Brian Kim

Repeated noise exposure and occupational hearing loss are common health problems across industries and especially within the mining industry. Large mechanized processes, blasting, grinding, drilling, and work that is often in close quarters put many miners at an increased risk of noise overexposure. In stone, sand, and gravel mining, noise is generated from a variety of sources, depending on the type of ore being mined as well as the final consumer product provided by that mine. Depending on the source of noise generation, different strategies to reduce and avoid that noise should be implemented. The National Institute for Occupational Safety and Health (NIOSH) has evaluated the noise profile at three operational surface stone, sand, and gravel mines. A-weighted sound level meter data as well as phase array beamforming data were collected throughout the mines in areas with high noise exposure or high personnel foot or vehicle traffic. Sound level meter data collected on a grid pattern was used to develop sound profiles of the working areas. These sound contour maps as well as phase array beamforming plots were provided to the mines as well as guidance to modify work areas or personnel traffic to reduce noise exposure.

Jan 6, 2022

By D. H. Rubisov, V. G. Papangelakis

Sulphuric acid pressure leaching is the process of choice to recover nickel and cobalt from laterites with variable iron and magnesium contents. The latter influences the acidity levels required for effective leaching of nickel and cobalt, and during leaching, iron is rejected in-situ as hematite. Classical solid/liquid separation is performed via a CCD circuit, the performance of which depends upon the size and shape of precipitated particles. In this paper, precipitates obtained by acid-leaching of various lateritic feeds at 270°C are characterized using SEM/EDX and laser particle size analysis. It is shown that as acidity increases, the shape of the precipitates gradually changes from platelets to spheres, thus improving the S/L separation properties of the residue. The use of hydrogen ion concentration “at temperature,” calculated from a speciation analysis, allows the explanation of this change of morphology independently of the type of the ore feed. The possibility of precipitating magnesium sulphate “at temperature” is also discussed. In order to take advantage of this precipitation for scale reduction (as has been proposed in the past) without compromising the residue quality, [H+] “at temperature” must be controlled within an optimum range.

Jan 1, 2000

By Cz. Mora, A. Pawelczyk, D. Hreniak, P. Nowak, A. Dyonizy, S. Strek, W. Strek, K. Grabas, A. Ostrowski

Globalization and a growing demand for limited raw material resources have forced changes in the approach to the supply chain. This is particularly true in the case of rare earths, which are regarded as one of the most important development indicators of modern technologies. To ensure a secure supply of commodities, the European economies have been prompted to investigate REE recovery from sources which until recently, for technical or economic reasons, were considered not sufficiently attractive. An interesting example is apatite phosphogypsum waste dumps. The REE content in these waste dumps averages around 0.5-1 %. One of the most important phosphogypsum locations in Poland is the Lower Silesia region where a phosphoric acid Chemical Plant "Wizów" operated for several dozen years. In this work, rare earths are leached from the phosphogypsum crystalline structure by a chemical treatment and can then be separated into individual chemical compounds. The technology used in these recovery tests, matches up to a coherent European raw materials policy supporting effective management of resources and promoting waste materials recycling.

Jan 1, 2014

By J. T. Dunham

Zirconium has possible use in industry where severe corrosion conditions are encountered because it resists attack from a variety of corrosive environments. However, very little experimental testing has been done to evaluate the corrosion behavior of zirconium when simultaneously subjected to high tensile stresses and exposed to corrosive environments. This investigation was initiated for an evaluation test, but was limited to environments consisting of ferric chloride solutions which were known to attack zirconium and were shown to promote stress-corrosion cracking in preliminary tests. Tests for cracking susceptibility were conducted by the Bureau of Mines to show the effect of stress, solution concentration, air aeration of solution, and the method of mechanical processing. Tensile stress was applied to the specimens by a constant-load method which proved more reliable than a constant-strain method.

Jan 1, 1961

By John P. Coughlin

The Bureau of fines has tested a portable microseismic processor recorder at the Galena Mine, Wallace, ID, both in an environmentally controlled enclosure and, with minimal protection, in a working area of the mine. In both trials the device demonstrated effective and reliable data acquisition capabilities.

Jan 1, 1985

By Davis RA, Wasp EJ, Cowper NT

The transportation of solids by pipeline is not new. In 1891 a United States patent broadly covering a method of pumping coal with water was granted to W. C. Andrews. His pilot plant was constructed on what is now the site of the New- York Public Library in Manhattan. His process was applied to pumping coal mine waste back into the worked out portion of coal mines. On October 26, 1967, the world's first long distance iron ore slurry line was put into service by Savage River Mines. The commissioning of this 5.0 million dollar installation climaxed three years of development, testing, and construction and proved the Company's faith in pioneering' this unique transportation method for iron ore. This paper will discuss some of the more pertinent items in connection with that three-year period. Also to be discussed will be the operation of this line during the past eleven months.

Jan 1, 1969

In view of the increasing environmental regulations that have been promulgated all over the world in the last 30 years, non-ferrous smelters and refineries have learnt and adapted to treat effectively metals'-containing process waste streams that need to be bled from the plant. However, anions such as sulfates, chlorides and fluorides-presently not a major problem ?are coming under increasing scrutiny and need to be addressed in the near future. The current paper reviews options for waste water treatment with reference to: a) types of waste streams processed b) process chemistry c) discharge options d) recovery and reuse of water and e) solids disposal. Methods to obtain zero liquid discharge ?a possible solution to eliminate discharge of above anions and residual heavy metals- are discussed with case studies. The long term goal of any non-ferrous smelter plant should be to have a zero liquid discharge philosophy-an approach that would become an epitome of water reuse and conservation.

Jan 1, 2009

By V. B. Dale

This is one of a series of reports covering the mineral resources of the Nation. It describes briefly most of the known tungsten deposits in Yuma, Maricopa, Pinal, and Graham Counties, Ariz. Most of those described were examined by the author. An effort was made to determine the position of the various deposits by section, township, and range and to give accurate road direction to each property from a prominent landmark. All available maps have been used in making these determinations, but in unsurveyed areas it was necessary to make approximate projections of subdivisions. The township and range numbers refer to the Gila and Salt River base and meridian.

Jan 1, 1959

The application of biogeochemical methods in mineral exploration in semi-arid to arid environments in Western Australia has been investigated in an area near Norseman.The study involved a comparison of trace element characteristics of rock, soil and plants in the vicinity of the Pioneer BB prospect, where nickel-iron sulphide mineralization occurs in a "greenstone" sequence of ultrabasic, basic and sedimentary rocks.Analyses of unweathered and partly weathered rock from diamond drill cores show the ultrabasic rock to be highly variable with respect to Ni, Cu, Co, Zn and Mn.Samples of weathered bedrock and overlying soil were analysed for total trace element contents and for the trace elements associated with secondary iron and manganese oxides. Approximately 30 per cent of the total nickel content of the weathered basic rock is associated with secondary iron and manganese oxides, compared with approximately 15 per cent in the weathered ultrabasic rock.The soil has a sufficient residual content to provide a reliable indication of the chemistry of the underlying rock. Total trace element analyses of the -89 mesh fraction show strong anomalies for nickel and copper over the mineralized zone. Important amounts of nickel, cobalt and, to a lesser extent, copper are apparently associated with secondary iron and manganese oxides in the soil.Melaleuca sheathiana (tea tree) has been used to study the relationship between soil and plant chemistry. No strong relationship between plant and rock type was observed. Analyses were made of leaves, twigs, wood, bark and roots, and all plant organs were found to have anomalous nickel and copper contents near the mineralized zone. Leaves were found to give the best contrast in the anomalous area and to show fewer erratic values than other organs. It is concluded that the uptake of trace elements by tea tree is low in the semi-arid to arid environment of Western Australia, but that analyses of the plants do reflect the presence of mineralization.

Jan 1, 1973

By Kássio Nogueira Cançado

A perda de temperatura das barras de aço no intervalo entre a saída do forno e a entrada do laminador é fator determinante no processo de laminação e na qualidade do tubo produzido. O estudo feito tem como objetivo modelar matematicamente o resfriamento destas barras durante o transporte entre o forno e o laminador, permitindo avaliar a temperatura mínima necessária para desenfornamento e também o máximo tempo de transporte sem comprometer o processo de laminação, possibilitando um melhor setup dos equipamentos reduzindo os custos de produção. Os resultados obtidos com o modelo matemático de resfriamento foram comparados com valores reais de temperatura coletados através de campanhas de medições com termopares instalados em uma barra e com medições de pirômetro. Valores de temperatura foram coletados com termopares em barras de 270, 230 e 180 mm de diâmetro. As medições com pirômetros foram feitas em barras de 180 mm de diâmetro. O modelo de resfriamento apresentou para todos os casos erro relativo às medições inferiores a 3%.

Aug 17, 2017

By Fabio Tavares Chamonge

Este trabalho visa mostrar os principais benefícios alcançados na qualidade dos produtos e a evolução da produtividade nas linhas de produção da Laminação a Frio com a estabilização operacional da nova Decapagem. Os recentes investimentos na modernização tecnológica, com a aquisição e implementação da nova Decapagem com os recursos modernos de controle e automação permitiu que houvesse uma evolução significativa da qualidade dos produtos, eliminando o desvio, reduzindo o descarte e melhorando a produtividade ao longo do processo de fabricação. Com inicio de funcionamento da nova Decapagem possibilitou processar bobinas com maior peso, maior flexibilidade na formação de bobinas soldadas e menores descartes por qualidade, estes fatores afetaram positivamente o peso médio na saída da Decapagem. A melhoria do material processado na nova linha proporcionou elevação da produtividade do Laminador de tiras a frio, considerando os aspectos: oleamento, planicidade, peso de bobina, solda e isenção de manchas e defeitos superficiais. O processo de Encruamento também foi beneficiado com peso de bobina e melhoria da forma do material. O produto final e os processos de acabamento também tiveram impactos positivos dos resultados obtidos na Decapagem 3.

Aug 16, 2017

By J. D. Rice, S. C. Pitzer, C. E. Thomas

Interpretation of pressure build-up data obtained in the conventional manner has often been difficult because of the deviation from theoretical behavior. Major causes of this deviation have been attributed to damage and afterflow, and to fluid redistribution in the wellbore which, in extreme cases, can result in a pressure hump in the early portion of the build-up curve. Theoretical investigations show that bottom-hole pressure is definitely influenced by phase redistribution in the tubing column during surface shut-in tests, and that the magnitude of the effect is sensitive to the producing gas-oil ratio and stabilized rate of flow in the well. For field experiments a wire-line tubing packer, which can be run in the tubing against a stabilized flow rate, was developed for bottom-hole shut-in tests. By use of this bottom-hole .shut-in method, pressure humps previously observed in surface shut-in tests were completely eliminated and the effects of afterflow minimized. Analog and digital computer studies have been made to obtain theoretical curves for comparison with field curves, and remarkable agreement between the results of bottom-hole shut-in tests and theoretical curves has been obtained. INTRODUCTION Pressure build-up data from shut-in wells have been used by the petroleum industry to determine the permeability of the formation, to estimate wellbore damage, to evaluate the static reservoir pressure and to speculate reservoir volume. Calculation of these factors is based on methods of analysis developed for theoretical systems whose build-up curves have a charac- teristic shape when the wells are shut-in at the sand faCe.1,2,3,5,8,10 However, field curves obtained by conventional surface shut-in methods do not always exhibit this characteristic. Such factors as stratification, rock heterogeneities and irregular reservoir geometry can cause the character of a build-up curve to deviate from that predicted by theory for a simple system. In addition, all field build-up data are affected by the methods utilized in obtaining the measurements. Conventional surface shut-in techniques allow two effects to occur which contribute directly to the manner in which pressure builds up at the sand face. The first, afterflow, has been recognized for some time and methods are available for estimating the magnitude of its effect and for correcting its influence.' The second, phase segregation in the tubing column after shut-in, has been reported only recently and appears to exert a considerable influence on the character of field build-up curves.!' In extreme cases, phase segregation can produce "pressure humps" in the early portion of the build-up curve. Such curves have been considered anomalous and have defied analysis. It is the purpose of this paper to discuss the effect of phase segregation in the tubing string during build-up and to present a bottom-hole shut-in technique for obtaining field build-up data which minimizes the influence of afterflow and eliminates phase segregation effects. It will be shown that reliable reservoir information can be calculated from build-up measurements obtained using this method, even though conventional surface shut-in tests on the same wells yield anomalous data. DISCUSSION OF PHASE REDISTRIBUTION EFFECTS Some of the effects of phase redistribution on pressure build-up curves have been described previously by Matthews and Stegemeier" who have presented evidence that phase segregation is responsible for the pres-

By Jack L. Woodward

The evolution of surface mining equipment has resulted in larger, faster haulage units, loaders, etc., resulting in increased demands on steering technology. Careful analysis of these systems was warranted to determine if steering-related safety problems have been introduced. The objectives of this program were to: 1. Define the generic types of steering systems being used on mobile mining equipment used in surface mining operations. 2. Gather information on steering-related accidents in mining operations. 3. Assess the need for initiating government-sponsored research into steering system technology. A comprehensive literature survey was conducted concurrent with extensive contacts with mining operations, mining equipment manufacturers, steering system component manufacturers, and government agencies. A Technical Evaluation Group composed of representatives from the above organizations was formed to review the data gathered. It was concluded that the steering systems in use on surface mining equipment are reliable and do not present a safety problem. The Society of Automotive Engineers, Inc. is active in pre-paring voluntary consensus standards to assure that the minimum levels of performance are defined for industry.

Jan 1, 1979

[*E. O'C. Acker '86 Jinzoc Adachl '88 T. H. Aldrich '96 *Truman H. Aldrich '78 Walter H. Aldridge '89 *Anson W. Allen '87 John H. Allen '84 *Thomas Andrews '94 *William R. Analeby '90]

Jan 1, 1946

By F. W. Gray

Summarized Foreword This paper is one of a series arranged by Institute Divisional Committees for the Fiftieth Anniversary Meeting, reviewing the experience of the major mining and metallurgical industries during the life of the Institute. The viewpoint is national and broadly technical. Geology is stressed on a continental scale without regard for provincial boundaries. The boundary between Canada and the United States is, however, so decisive a factor in our coal-mining economics and our political evolution that mention of its implications cannot be avoided. The Laurentian Shield in Canada makes the occurrence of coal deposits a geological impossibility between the St. Lawrence Lowlands and the Great Plains. All but five per cent of Canadian coal resources occur west of Winnipeg. The utilization of this ninety-five per cent of our coal wealth has to date been a consequence of transcontinental railways' development, and the small fuel needs of thinly populated wheat farming and cattle-raising territory, in what- to judge from the development of mixed farming and greater population density of Manitoba- is merely an initial stage of agricultural intensification and accordant population growth. There is no useful purpose in measuring coal resource against consumption rate in the West as a whole, because the resource is but partially known, and it is difficult to believe that industrialism based upon coal utilization is in any but its infant stage of growth. Canada west of Winnipeg possesses, moreover resources of petroleum and natural gas, which, together with the power-potential in the long watershed of the eastern slope of the Rocky mountains, give to population centres such as Calgary and Edmonton a choice of energy resources that is almost an embarrass des riches.

Jan 1, 1948

By Thomas R. Bur

The strain and pressure gage methods for evaluating the relative performance of explosives in rock were compared. This comparison was based on a study of the responses of strain and pressure gages to explosion-generated seismic waves. Several explosives) representing a wide range of detonation pressures) were used. In general the relative performance of these explosives) as determined from amplitude) impulse parameter) and energy parameter measurements) is the same if the compressive portion of the strain pulse and the comparable portion of the pressure pulse are considered. Other similarities and differences of the two methods are also discussed.

Jan 1, 1967