Search Documents

By T. K. Bose

According to the Intergovernmental Panel on Climate Change (IPCC), the average global temperature has risen over the last century. If this trend continues over the next century, the IPCC projects a significant increase in temperature and a rise in sea level. The changes in climate could adversely impact human health, agriculture, water resources and ecosystems. Most national and international agencies have concluded that our use of carbon-rich fuel is responsible for global warming through the greenhouse effect. In the future, the situation may get worse if the increased need for energy in countries like China, India and Brazil is fulfilled by burning fossil fuel. Advanced natural gas-fuelled vehicles have the potential to reduce carbon monoxide and reactive hydrocarbon emissions substantially compared to gasoline vehicles. Further environmental benefits can be realized by using a blend of natural gas and hydrogen. Such an approach will help create an infrastructure for an eventual transition to hydrogen.

Jan 1, 2005

By J. W. Meier

Introduction The great importance of air warfare during World War II and the introduction of large-scale air transportation and airborne operations created an immediate demand for large quantities of high quality light alloy products. Before this war, the use of magnesium, the lightest structural metal, was barely in the development stage, and considerable research work was needed to overcome difficulties in improving its properties and to attain uniform quality in mass production of magnesium alloy products. The Canadian Bureau of Mines was frequently called upon, by various agencies of the Armed Forces and of the newly established war industries, to examine magnesium alloys that had failed in fabrication or in actual service, and to advise on proper alloys and fabrication methods to be used. Failures in magnesium alloy castings were connected mainly with lack of knowledge of proper founding and surface-protecting techniques. Most of the defects were due to microporosity and faulty heat treatment. To aid the foundry industry, small-scale investigations were started on the effect of various factors in the casting technique in order to improve the quality of the products. These investigations were made in co-operation with representatives of the Armed Forces and the Canadian magnesium industry. This work was later co-ordinated into a broad research programme on magnesium alloys, comprising problems on melting, refining, various casting methods, heat treatment, and testing of properties of standard and special alloys. This research programme? is still in force, and the present paper contains some results of the first series of investigations on magnesium casting alloys carried out at the Experimental Foundry of the Bureau of Mines.

Jan 1, 1948

By WILLETT G. MILLERS

GENERAL RECEPTION COMMITTEE.-Willett G. Miller, Chairman; F. G. B. Alan, Hon. Frank Cochrane, Eugene Coste, Thomas W. Gibson, Cyril W. Knight, J. C. Murray, 0. N. Scott, Alan Sullivan, J. B. Tyrrell, J. W. Wells, A. B. Willis. COBALT RECEPTION COMMITTEE.-Arthur A. Cole, Chairman; Will. Ask with, R. W. Brigstocke, Robt. Bryce, Fred Coombs, M. I. Culbert, I. R. Drummond, J. W. Evans, A. Ferland, F. N. Flynn, E. L. Fraleck, S. R. Heakes, Joseph Houston, D. L. Jemmett, I. R. Jones, Major Leckie, Capt. Jack Leckie, R. W. Leonard, W. H. Linney, Alexander Longwell, Frank Loring, Murdock McLeod, John Martin, D. B. Rochester, W. E. Running. COBALT RECEPTION COMMITTEE (Ladies).-Mrs. A. A. Cole, Mrs. A. Edwards, Mrs. R. Jennings, Mrs. S. H. Logan, Mrs. A. Longwell, Mrs. H. F. Marsh, Mrs. J. Smith. SUDBURY LOCAL COMMITTEE.-Mayor L. O'Connor, Chairman; S. Fournier, Secretary; A. H. Beath, W. J. Bell, F. B. Bennett, D. M. Brodie, J. S. Buchanan, F. C. Busby, Wm. Chalmers, R. Dorsett, W. A. Evans, John Frawley, J. S. Gill, A. B. Gordon, J. G. Henry, T. N. Kilpatrick, Major Leckie, Chas. McCrea, John McLeod, Wm. McVittie, R. Martin, R. S. Mitchell, J. H. Morin, J. A. Orr, James Purvis (President Board of Trade), C. R. Reid, Major Smith, W. W. Stull, J. F. Templeton, S. E. Wright. The first session, held in the Banquet Hall of the King Edward Hotel, was called to order Tuesday, July 23, 1907, at 2.30 p.m., President John Hays Hammond presiding. Prof. Willett G. Miller, chairman of the General Committee, introduced Alderman J. J. Graham, who, in behalf of the City of Toronto, extended a hearty welcome to the members and guests of the Institute. To this welcome, President Hammond replied in a few well-chosen and hearty remarks. In the hall in which the session was held there was exhibited a fine, full-length, life-size portrait of Dr. Rossiter W. Raymond, in 1871 Vice-President and acting President, in 1872, 1873 and 1874 the elected President, in 1876 and 1877 Vice-President, in 1883, by appointment of the Council, and for the last 24 years by annual election, Secretary, of the Institute. Dr. James Douglas, of New York, N. Y., on behalf of numer-

Sep 1, 1907

By Michel Ruel

"PID loops – also known as base layers or regulatory controls – form the foundation of any plant’s control layer and it is generally accepted that PID loop health has a direct impact on the plant’s bottom line. Keeping these thousands of control loops in good health has a direct impact on the plant’s bottom line: it reduces variability, improves quality and throughput, and decreases energy costs and raw material usage. This has been well proven and documented in many articles. In the last ten years, technology has evolved: control engineers can now keep track of control loop performance and link it to the root causes of variability. However, they lack industry-wide best practices and criteria for determining what can be considered as excellent, good, fair, or poor performance. To ensure that PID control loops continue to perform well and meet their objectives, control engineers need a combination of (a) an appropriate monitoring technology and (b) best practices for doing the maintenance of base layer controls.Most plants have limited resources and operate with an increasing number of constraints; therefore, using the right tools and including reports in daily workflow is key for success. This paper suggests roles and responsibilities of key players needed to work toward control performance best practices and discuss organisational changes to succeed.INTRODUCTIONAlthough PID controllers are reliable workhorses in the process industry, they are often underrated. Since the 1980’s, computer control has evolved and the control algorithms used by control engineers have become increasingly complex. However, PID controllers still handle over 90% of the control loops in operating plants. Table 1 shows the savings that can be realized by achieving best-practice in several different process control categories (Brisk, 2004). The savings are expressed as a percentage of production costs."

Jan 1, 2011

By A. Roy MacLean

This paper outlines the changes in modern-day coal mining that have been brought about by the increased cost of labour and the use of new and highly efficient equipment. In the latter category are mentioned the ramp-plate, the Bretby cable carrier, armoured face conveyors and the shearer-loader. Greater productivity and increased safety are emphasized.

Jan 1, 1969

By D. Puckett

The feasibility of maintaining equipment location, personnel location and vital statistics in surface and underground mining operations has increased with advances in radio frequency identification (RFID) technology. The paper addresses the use of this technology, relatively new in the mining industry, to track surface equipment in mine pits, loading points, and processing facilities. Specific applications are discussed including a simplified and a complex truck tracking system and an automatic pit ticket system. The paper concludes with a discussion of the future possibilities of RFID technology in mining, such as monitoring biofeedback of personnel (heart and respiration rate, body temperature, exertion level, etc.) repetitious movements to study work habits, and logging air quality via personnel sensors.

Jan 1, 1996

By S. E. James

EAF dust has been listed as a "hazardous waste" due to the presence of lead and cadmium, and at times chromium. The 550,00 tpy production of . .EA]' dust, estimated for the United States alone, contains more than 10,000 tpy of lead and about 250 tpy of cadmium in addition to nearly 1'00,000 tpy zinc. Even though the listing of .EAF dust as a hazardous material stimulated extractive metallurgical work worldwide, process development efforts have focused only on the recycle of the potentially-valuable zinc units. However, the recycle of the lead and cadmium, while not lucrative, is the more critical effort. Horsehead Resource Development Company, Inc. (HRD), in conjunction with its sister company, Zinc Corporation of America (ZCA), has taken a unique approach to total recycle of the toxic heavy metals found in the EAF dust. Impure oxide, produced by either a Waelz kiln or FLAME REACTOR Process and containing the lead and cadmium, is calcined in a rotary kiln at Palmerton, Pennsylvania, to produce a refined zinc-rich intermediate for ZCA's electrothermic zinc plant at Monaca, Pennsylvania. During the calcining operation, lead and cadmium are concentrated in a fume product and shipped to ZCA's electrolytic plant at Bartlesville, Oklahoma. At Bartlesville, a new hydrometallurgical circuit has been constructed and the existing cadmium plant expanded. The combined facilities permit the total recovery of cadmium to refined metal and the lead to .a silver-rich intermediate, which is sold to lead smelters. In this paper the Waelzing, calcining and new leaching facilities will be described.

Jan 1, 1990

By Stanley W. Ivosevic

The South-Central area of the Osa Peninsula, Puntarenas Province, on the Pacific coast of southern Costa Rica, may have produced on the order of 30,000 kg (100,000 troy oz) of gold since prehistoric times. The Peninsula lies along an 800- to 900-km-long belt of late Mesozoic eugeosynclinal rock deposition, hydrothermal activity, and deformation (Campanian). The oldest rocks exposed in the area are basalt and tuffaceous mudstone of the Late Jurassic or Cretaceous Nicoya ophiolite complex. The Nicoya Complex is overlain by weakly lithified Pleistocene Older Sediments, predominantly conglomeratic sandstone and derived from erosion of the Nicoya Complex. Erosion reduced the Complex to a surface of high relief, so that the detrital source was in the area originally; the source retreated with subsidence. Stratigraphically, the Older Sediments are followed by surficial deposits of intermediate age, consolidated Younger Sediments reworked from Older Sediments, and unconsolidated Holocene surficial deposits reworked from Younger Sediments. The most prominent structures are a northeast-trending anticline and northeast and northwest fault sets. Some deformation was Cretaceous, but folding and much faulting occurred after deposition of the Older Sediments. Remnants of plainlike features and destructional terraces on the Older Sediments attest to stepwise downcutting of the terrain during successive stages of uplift. Near the end of this process, the present valley floors and coastal headlands developed. During a probable epeirogenic rise in sea level, Younger Sediments filled the valley bottoms and an aggradational coastal plain developed. Sea level dropped by stages and with some reversals to its present position; this caused stepwise incision of the valley fill, stepwise beveling of the coastal plain, and development of the present wave-cut platform. Spilitization around the time of the Campanian orogeny caused some parts of the Nicoya complex to be calcitized and others to be silicified. Gold, pyrite, and probably additional silica were introduced during subsequent hydrothermal activity. Native gold was eroded from Nicoya Complex lodes and reconcentrated through three generations of placer gold deposits. First, the gold was deposited as a detrital.

Jan 1, 1977

By Oliver Bowles

THE ADVERSE CONDITIONS that have gripped industry during recent years have to some extent submerged technical developments under the more pressing demands of economic problems. Progressive operators, nevertheless, have given attention to improvements in processes and equipment even when sales were at a low ebb. The array of facts relating to technical advancement here presented, although doubtless incomplete, is sufficient to indicate that the spirit of inquiry and research has not been quenched by adversity. During the latter part of 1933 a new element has focused interest more fully on improved methods of quarrying, mining, and preparation of nonmetallic minerals. Codes established under the NRA have fixed minimum wages, reduced working hours, and tended to establish selling prices .on a basis of reasonable profit. Labor adjustments will in many instances increase the cost of production, and stabilization of selling prices will tend to emphasize quality and service rather than price as sales arguments. These new conditions point to a growing necessity for improving technique in the interest of reducing cost of production and improving the quality of products. Thus, technology is linked with economics more firmly than ever.

Jan 1, 1934

By R. V. Ramani

"Exposure to respirable contaminants in mine atmospheres has long posed a serious hazard to miners. The control of these hazards, some of which can have sudden and catastrophic effects and some others, slow and long enduring consequences, has been a major concern for labor, management and government alike. This concern has manifested itself in four primary mechanisms of control -- (1) regulatory control through minimum standard setting by the passage of mine health and safety laws, (2) engineering control through design and operation of 'mines according to the best recommended practices, (3) medical control through periodic physical examinations, wearing personal protection devices, etc., and (4) legal and social control through workmen's compensation laws for occupation related health deterioration:-The respirable contaminants in mine atmo¬spheres are toxic and explosive gases, toxic and explosive dusts, diesel exhaust particu¬lates, radon progeny, etc. Perhaps the most important of all these and the most widely occurring in mine atmospheres is respirable dust, an inevitable product of fragmentation, a unit operation fundamental to all mining operations. In fact; the-most serious health hazard for workers in the mining and minerals processing industries is still the exposure to respirable dust, and solutions to the problem of respirable dust disease remain to be found.The 1969 Coal Mine Health and Safety Act and its provisions for the respirable dust standards in underground coal mines are briefly reviewed. An overview of the research accomplishments in meeting the standards is presented. The current state of knowledge on the effectiveness of the standards and the new and emerging problems are discussed. A brief summary of the research programs of the Generic Technology Center on Respirable Dust is presented.In general, underground mines are becoming increasingly safe. The mine atmospheric environment is definitely improving * Professor and Head, Department of Mineral Engineering,-The Pennsylvania State University, University Park, PA for the better. Significant progress has been made in lowering the dust levels in mines. It is generally agreed that mines are less dusty today than they were a decade ago. However, as long as the risks of occupation-related diseases are not completely eliminated, vigilance can hardly be relaxed, and the search for engineering solutions must be intensified."

Jan 1, 1988

By G. Chahal, L. C. So, S. Faucher, S. Mostaghel, S. -Y. Oh, S. K. Lee

Slag dumping and water granulation are the most commonly used slag treatment methods in the metallurgical industries. In both processes, water is present (by desire for cooling and dispersion or as a result of rain accumulation) and thus equipment and operations are designed to minimize and mitigate the risk of steam explosions resulting from the inappropriate contact of slag with water. Slag handling practices have, therefore, never been inherently safe; even good design, operation, and maintenance are not sufficient to prevent explosions or other related injuries from occurring. For slag handling to become inherently safe, our industry must eliminate the potential contact of water with molten slag. This is today feasible with the advent of dry granulation technologies, a review of which is presented, and it thus falls to us, in the metallurgical sector, to lead the way in their final stages of development and adoption. Furthermore, while slag dumping and water granulation offer some metallurgists the means of valorizing their slag as a by-product, for most, this is not the case. The energy in slag is lost through dumping and water granulation processes, and where slag is sold as a by-product, it is for its chemical content only. Here, dry granulation processes also offer advantages including the production of by-products which hold value in both their chemical content and physical properties and heat recovery. Dry granulation, therefore, augments the methods by which slag may be valorized over traditional processing methods.

Jan 1, 2015

By G. Grassmück

The question of whether the air curtain principle could be used under conditions prevailing in Canadian metal mines was investigated. A vertical, portable BERRY air curtain was tested, at first in a wind tunnel built at Ecole Polytechnique at full scale (8-by 8-ft cross section) to simulate a drift and its lateral connections, and then in the haulage ways of a metal mine under actual conditions. The results permit us to predict under what conditions this type of air curtain is capable of acting as an air stopping or flow regulator and how it could be further developed.

Jan 1, 1969

By H. J. Oterdoom

SMS Group (SMSG) has always been concerned about safety aspects of electric smelter plants for the ferro-alloy and non-ferrous industry. The awareness for safety increased significantly over the past decades and also SMSG contributed with its design features to a safer operation. Today, safety aspects are not only part of the smelter design but also of the overall plant layout. Explosions in electric smelters are rare, but have a huge impact on peoples’ lives, on equipment and on production. For this reason, SMSG wanted to have a better overview of explosions within the smelting industry in order to see if useful statistics could be extracted. Generally, there is a lack of statistics regarding explosions in the electric smelting industry, and not enough information is collected or published. A significant portion of the explosions seems to be water related. Many companies, both operating and engineering, are trying to handle the risks of water, and apply methods to detect water leakages. Installing such a system is a management decision and management has then to make sure the system is properly implemented. The disadvantages and limitations of these systems should be carefully considered and communicated to operators and authorities.

Jan 1, 2015

By Jr. Raleigh

As part vi the development of the Coal Quality Expert (CQRN) --a computer program capable of predicting the impacts of coal quality on power plant performance, costs, and emissions control--several nationally important coals are being characterized to augment the coal quality database associated with the software. The project is sponsored by the U.S. Department of Energy and the Electric Power Research Institute (EPRI) under the Clean coal Technology Program. Since 1989, CQ Inc. (a subsidiary of EPRI) has characterized seven bituminous coals from Alabama, Illinois, Kentucky and Oklahoma and six sub-bituminous coals from the Powder River Basin (PRB) in Montana and Wyoming. Coals from the PRB region--being burned more frequently in Midwestern and southern power plants to reduce emissions of sulfur oxide compounds--can sometimes contain significant concentrations of potentially toxic elements. Although no limits were imposed on air toxics emissions from fossil-fuel fired utilities by the Clean Air Act Amendments of 1990, future regulations may be implemented at the conclusion of Federally-mandated emissions studies. One possible result is that any increased utilization of coals, including those from the PRB, may depend on the potential for removing toxic trace elements prior to combustion.

Jan 1, 1993

By S. Kariyawasam, R. McNealy

Pipelines are subject to multiple threats often requiring quantification of pipeline risk and engineering evaluation of in-line inspection and other data to effect discovery of conditions defined by the regulation. Public concern and pressure from regulatory bodies are accelerating the need for pipeline operators to formalize and intensify their approach to integrity management. Most operators need a phased approach to progressively adopt the most relevant and needed assessments. The organized and relevant assessment steps need to be introduced according to data available and maturity of the integrity management program. Each refinement to the quantification offers distinct advantages to the user. In this paper, the progressive integrity assessment solutions using quantitative methods are presented. Methodologies for engineering evaluation of integrity in-line inspection data for immediate and future integrity are summarized. Corrosion is used as an example, but the approach is applicable to any time-dependent defect based hazard. Strategies for pipeline integrity management are discussed.

Jan 1, 2005

By Maria I. De Rosa

Combustible materials, when burned, produce toxic gases and smoke, which may vary dramatically from one material to another, with resultant different total toxicity and smoke obscuration levels. This U.S. Bureau of Mines report presents smoke property data acquired for a variety of mine combustibles and shows that there exists a correlation between the smoke properties, the relative toxicity, and the smoke obscuration levels of those combustibles tested. These correlations can be used to devise simple, standard tests for determining the toxic and smoke obscuration hazards of mine materials during fire.

Jan 1, 1989

By A. R. Taylor

This report describes the design, construction, and operation of a low temperature adiabatic calorimeter for measuring heat capacities of solids or liquids from 60° to 300° K. A brief discussion of the basic theory involved in chemical thermodynamics and the problems involved in obtaining accurate experimental data is presented. The operation of the calorimeter was tested by measuring the heat capacity of a sample of benzoic acid obtained from the National Bureau of Standards over a temperature range of 60° to 300° K. The measured heat capacity values of the benzoic acid compared favorably with similar values obtained by the Bureau of Standards, the maximum deviation being 0.5 percent. THEORY A brief discussion of the basic theory involved in chemical thermodynamics will illustrate the applications of heat capacity data and the problems involved in obtaining accurate experimental data.

Jan 1, 1962

By P. A. Korpi

In March of 1978 the first set of Angular Spiral Liners utilized in grate discharge ball mills for wet grinding was put into service in the San Flanuel Concentrator of Flagma Copper Company. The use of these liners has decreased grinding media consumption by 19.2% and grinding energy consumption by 15.8%. In addition a 1.1% increase in grinding throughput is being realized through the use of the system. This paper describes the Angular Spiral Lining System and reviews the test program at the San Manuel Arizona Concentrator. Operating parameters are discussed in addition to the current testing program to futher optimize the system.

Jan 1, 1982

By Patrick Tassot

Increased worldwide highly competition in steel market imposes innovative measure for the steelmaker targeting cost reduction and climate-friendly steelmaking process in order to have the ability to withstand the pressure of the market. At the same time the demand for high purity and highest quality steels continues to grow from year to year, especially in the sector automotive in transportation of oil and gas, in the construction Industry and in the manufacture of heavy plate. As they allow producers to be up to the requirements while allowing expanding their product mix, new secondary metallurgical treatments have become a must additionally to standard equipment elements of steel plants modern. Most of these treatments occurs in the steel ladle increasing the pressure to ensure a reliable and as possible neutral reactor. Intelligent solutions for refractory lining ladles should integrate better adaptation to the operational process parameters and the high reliability/availability at the best cost/performance. This challenge has conducted Refratechnik to develop new concepts to overcome the frontier between shaped and unshaped materials and that’s what will be covered in this paper.

Aug 17, 2017

By G. C. Presley

With plant construction scheduled for the Spring of 1997, U. S. Zeolites will become the new source for quality in natural zeolites. The company will selectively mine, dry process, package, and market a very high quality clinoptilolite possessing many unusual properties. These unusual chemical and physical properties provide a multitude of industrial, commercial, and consumer applications. Extensive testing has determined many potential applications.

Jan 1, 1997