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By N. Powell, R. J. Pine

An algorithm is proposed for updating the probability of slope failure on the basis of sequential testing using Bayesian probability theory. The approach is novel and computationally straightforward since, unlike other methods, updating of the probability of failure is carried out directly. This is because the probability is treated as a random variable whereas other methods have considered it as a purely deterministic value or as a function of shear strength parameters that are updated individually. The prior information required for the Bayesian analysis is obtained by a conventional probabilistic analysis. An exponential distribution is then used for the probability of failure, applying the principle of maximum entropy. This distribution is continually updated for individual slope cells, where repetitive excavation creates several such cells and a corresponding series of Bayesian estimates of the probability of failure is obtained. The approach is applicable to most simulations but there are limitations on its use. A more mathematically rigorous refinement using the beta distribution is currently under development

Apr 1, 1996

By Camille Fleuriault

Continuous development of lead recycling technologies has driven the increasing contribution of secondary lead in battery manufacturing over the years. This review presents and compares the different technologies available for pyrometallurgical processing of secondary lead materials. Smelting is most often achieved in reverberatory, blast, rotary or electric arc furnaces, using single or two stage routes. Thermal re fining is the most common technique used for the production of lead and its alloys. Some improvements in battery breaking technologies and emission control have also specifically contributed to improve the performance of the smelting and refining units. Recycling lead is facing the challenge of increasing production while meeting more and more stringent regulations. This review will also include an analysis of the current secondary lead market as well as an economic outlook for the years to come in regards to rapidly changing environmental standards.

Mar 1, 2018

By V. Songmene, R. Khettabi, J. Masounave, R. D. Njoya

L'augmentation régulière des règlements environnementaux et de la sécurité au travail deviennent de plus en plus strictes. L'usinage fait partie des opérations industrielles qui peuvent causer des problèmes de santé au travail et sur l'environnement. La plupart des particules de poussières produites pendant toutes les opérations d'usinage à sec ou lubrifie causent des nuisances environnementales graves. Le travail propose étudie l’influence des paramètres de coupe, des alliages et des états des matériaux sur la formation des copeaux et sur la génération de poussière lors de l'usinage à sec. Deux modes d'usinage (le fraisage et le perçage) sont abordés. Une loi reliant la ténacité des matériaux aux émissions de poussières est proposée. Les effets des matériaux et de leurs conditions, ainsi que des procédés d'usinage sur la génération des poussières ont été mis en évidence. Des mécanismes de formation de poussières sont identifiés et reliés à la formation des copeaux.

Jan 1, 2006

By Francis X. McCullough

After OSHA published a Notice of Proposed Rulemaking on August 5, 1983, to revise its standards for Underground Construction, many contractors and their representative associations became concerned by the sweeping changes in the proposed rule. After reviewing all of the evidence and testimony on file with OSHA, the contractors presented extensive written and oral testimony to the Department of Labor in Washington, D. C. to help insure that the final published rule would be effective without jeopardizing the economic viability of the industry. The results of those efforts, the entire OSHA rulemaking process, and the opportunity for the construction industry to participate in that process will be discussed.

Jan 1, 1985

By Eduardo Lozano, Vilem Petr

The use of explosives bring countless benefits to our everyday lives in areas such as mining, oil and gas exploration, demolition or avalanche control. However, because of the potential destructive power of explosives, strict safety procedures must be an integral part of any explosives operation. The goal of this paper is to provide a solution against the hazards which unfortunately accompany the use of explosives. For this reason, a blast shield is specifically designed and tested for protecting personnel against these unpredictable effects. This document will develop a complete analysis answering the following questions: what are the potential hazards from an air blast; what are their effects; and how can we be protected against them. In order to answer these questions, theoretical, analytical, and numerical calculations are performed. Finally, a full blast shield prototype is tested under blasting conditions proving its effectiveness as a safety device while explosives are used.

Jan 1, 2015

By Christopher Mark

Six decades ago, the most dangerous job in the USA was mining coal underground. Roof falls were responsible for half of the deaths, killing about 100 miners every year. Fast forward to 2016 and zero roof fall fatalities. Just three miners were killed by roof falls during the following 6 years. How did the mining community achieve this historic goal? This paper starts by analyzing the roof fall fatalities in 1968, categorizing them by their fundamental cause. Then, it shows how each type of roof fall was reduced over time, using snapshots of the fatalities occurring in subsequent decades. Along the way, it evaluates the influence of the regulatory environment, changing mining methods, and better ground control technology. The study found that in 1968 more than half of roof fall fatalities at large mines were attributable to an inadequate safety culture. The immediate effect of the 1969 Coal Mine Health and Safety Act was to reduce the riskiest activities, like needlessly going under unsupported roof. Other hazards, like large roof falls, required technological developments before they were brought under control. Roof Control Plans, which the US Bureau of Mines had been advocating since the 1920s, played a significant role throughout the process.

Mar 12, 2024

By Gordon L. Draeseke

"Before getting into more specific aspects of my talk today I should put in one disclaimer - one week in Mainland China and one day with Premier Kosygin does not make me an expert on Sino-Soviet affairs nor on Canadian-Chinese relations. Perhaps though there is a message in the fact that one meeting took place in relative openness in China and the other was at least partly in a bullet-proof limousine in Canada. I thought it might be interesting and appropriate to explain something of the forest industry to you who are engaged in the mining industry. Our industry, like yours, is based on a natural resource and the basic activity that we engage in is the extraction and conversion of that resource into saleable materials. However, the fundamental difference between our industries is that our resource is on top of the ground - easily visible and easily measurable, whereas yours is under the ground - difficult to find and, having been found, expensive to measure. A second difference is that ours is renewable while yours is extractive, and you must keep finding more to keep up reserves."

Jan 1, 1971

By Peter A. Cain, John C. Folinsbee

"A 4-ft.-diameter shaft has been drilled to a depth of 2,790 ft. in strong, hard, basic Precambrian rocks at Lynn Lake Manitoba. This was done on the property of Sherritt Gordon Mines Limited for the purpose of ventilating and developing the ""N"" orebody, which is located approximately 4,000 ft. south of the Farley shaft.The drilling was done under contract by two drilling companies. Peter Bawden Drilling (1964) Limited drilled the initial 12:1,4-in. pilot hole to a depth of 3,000 ft. Shaft Drillers Limited of Canada then reamed the hole to 4 ft. in diameter to a depth of 2,790 ft. At this point, the reaming was stopped because of the difficulty in passing a change in direction in the line of the pilot hole. The hole was completed by driving a raise 200 ft. from the 3000 level to the bottom of the 4-ft. hole using an Alimak raise climber.Cuttings from the reaming operation were directed into the 12:1,4-in. pilot hole, where they fell to the 3000 level and were removed by a mucking machine and standard mine development cars.The elapsed time from the start of the pilot hole to the completion of the reaming operation was ten months, with an average advance of 279ft. per month. There was a two-month delay between the completion of the pilot hole and the start of the reaming operation.The 12:1,4-in. hole was drilled in an elapsed time of 45 days from the time of setting up the rig. The average advance per day was 66.8 ft.The reaming operation was done in an elapsed time of 194 days. A one-month delay required to repair damaged equipment left 163 days for the drilling and setting-up operation, for an advance per day of 17.1 ft."

Jan 1, 1966

By Allen D. Look, Alan A. Sharp

"INTRODUCTION The bottoming of the United Verde sulfide pipe has shortened the expected life of the United Verde mine to a matter of a few years. First located in 1876, this Arizona mine has had a long period of activity, having reached a peak production in 1929 of over 71,000 trans of copper. Through these many years of successful operation, a safety program has evolved in keeping with the proficiency developed in mining the ore body. It is the purpose of this paper to record the safety practices in effect at this mine so that others may have the benefit of lessons ,learned through experience 'and years of work toward an improved accident record.ACKNOWLEDGEMENTSAcknowledgment 'is 'made to ,the Phelps Dodge Corp. for its cooperation in making available data contained in this paper, and to C. E. Mills, general superintendent; W. W. Little, mine superintendent; John Riordan, employment agent; and G. S. Leisk, safety engineer, for their helpful suggestions and information furnished.GENERAL INFORMATIONThe United Verde copper mine is situated just west of Jerome, Ariz., at an altitude of approximately 5,500 feet. Purchased by the Phelps Dodge Corp. in 1935, the mine employs approximately 500 men - 385 underground and 115 on the surface."

May 1, 1949

By G. R. Guillet

THE LATE Dr. D. F. Hewitt, Ontario's foremost authority on industrial minerals, was the first to point out the importance of urban minerals when he produced figures (Hewitt 1968) to prove that the Toronto-Hamilton area was Ontario's second largest mining camp in 1966 (Fig . 1). In that year, the value of mineral production within a 60-mile radius of downtown Toronto exceeded individually that of Steep Rock, Kirkland Lake, Timmins, Manitouwadge and Elliott Lake. Only the nickel and precious-metal production of Sudbury .surpassed in value that of Toronto's pits and quarries. Although that position was unchanged for some years during the early sixties, it was admittedly an unusual situation: gold was still pegged at an artificially low value; uranium was stagnant; and Texasgulf had not entered the scene. However, the point had dramatically been made. The combined value of production from hundreds of sand and gravel pits and dozens of limestone and shale quarries was of formidable proportions. The mining industry of the urban fringe could not be denied. Construction aggregates, cement, building stone and bricks were fueling an apparently insatiable appetite for urban expansion and redevelopment.

Jan 1, 1978

By A. M. King, J. M. Neilsen

"Roughness at varying scales is an important component of the shear strength of discontinuities. Small scale roughness can be assessed in drillcore and through laboratory testing of drillcore derived samples. Large scale roughness, or waviness, also plays an important part in peak shear strength and a number of methods for its incorporation into defect plane strength models are presented.A number of methods for capturing waviness data from exposed faces are reviewed. A method is presented for deriving waviness from downhole televiewer data, which is shown to be significantly more accurate than structural data derived from core logging. The method is based on work undertaken in the highly anisotropic bedded units of the Hamersley Province, Western Australia where televiewer surveys are routinely undertaken. Values of waviness are derived through a review of variation in dip resolved in the direction of the slope face. This method allows design engineers to incorporate large scale roughness in defect plane shear strengths at the design stage.INTRODUCTIONThere are a number of constitutive models currently being applied by rock mechanics practitioners in calculating defect plane shear strength parameters, such as Patton, Barton – Bandis and Hencher [1, 2, 3]. Most of these shear strength determinations are typically undertaken by determining the base or residual friction angle, and applying corrections for small and large scale surface roughness."

Jan 1, 2015

By B J. Monaghan, P Zulli, X F. Dong

In the lower zone of blast furnace (BF), slag trickles down through a packed bed of carbonaceous particles in the form of films, rivulets or droplets. During its downward flow, there are significant interactions occurring between slag and other phases, ie gas and packing particles. In particular, the interaction between gas and slag is closely associated with the key flow phenomena such as loading, flooding or channelling in the lower zone of the BF. With gas introduced laterally through tuyeres and slag flowing downward from the cohesive zone to the hearth, this interaction varies throughout the lower zone and in the cohesive zone:  strong cross-flow of gas relative to the slag occurs in front of the raceway  counter-current flow of gas and slag occurs in the upper parts of the lower zone  both strong cross- and counter-current flow of gas and slag around and within the cohesive zone. These interactions can be linked to furnace irregularities, affecting smooth operation and limiting production. Therefore, understanding the gas-slag interaction and its influencing factors remains critical for BF process control. In the current review, the physical behaviour and key influencing factors of gas and slag flow are initially examined. Numerical models describing gas and slag flows in a packed bed at micro-, mesoand macro-scopic levels, are reviewed. Each simulation approach has its advantages and limitations, as well as unique assumptions when used in BF process modelling. Applications of these approaches to gas-slag flow in key identified functional zones will highlight the differences between approaches and modelling outcomes. As no single approach can fully address all aspects of gasslag interactions, an integration of different approaches is considered an effective and beneficial method in providing a more complete understanding of gas-slag flow in the BF process.

Jun 19, 2024

By G. S. Rice, H. P. Greenwald, H. C. Howarth

"""Rock-dust barriers""5 as they are termed in this country, are for the purpose of confining a coal-dust mine explosion to the limited area in which it originates. These barriers were first tested in 1910-1911, with favorable results under the conditions of test, at the French official gallery which was then at Lieven, Department of Pas-de-Calais. Shortly afterwards the Bureau of Mines in the course of its investigation of all practical explosion-prevention methods tried barriers in the Experimental Mine near Bruceton, using the primary form of simple fixed cross shelves 20 inches wide extending over the passageway and laden with rock-dust. The Bureau termed them “Taffanel barriers"" in honor of the director of the Lieven testing station. The trials were made in conjunction with tests of explosibility of different coal-dusts.Experience showed that although the principle of barriers had merit when they were used for secondary defence, the primary form was uncertain in effectiveness. This led the senior author to design mechanically discharging barriers to be operated by the compression air waves which precede the flame of an explosion. For the better understanding of the principal involved, it is pointed out that the advance air waves are what make a coal-dust explosion possible by stirring up the coal-dust from the walls and floor of the passageway. If a barrier can throw inert dust into the air to form a cloud as dense or denser than that formed by the coal-dust, it will neutralize the explosiveness of the coal-dust, and the flame of the explosion will be extinguished. When the flame ceases, the pressure dies away in a short distance if the 'area that had been traversed by the explosion is not large."

Jan 1, 1930

By Iwueze Anaekperechi Rose

The International Labor Organization has declared mandatory adequate provision of safe workplace and safety for all workers in all occupations including the mining sector. Early scientists like Agricola (1559) who studied the health of Miners, found that there are peculiar health problems associated to their work and working environment. This unsafe working condition was one of the major factors that resulted to the Industrial revolution in England and eventually led to the establishment of regulations and laws guiding operations in all workplaces and workers in England and all over the world. Recent studies by Heinrich suggested chains of events of safety issues in the mining sector. Occupational injuries, accidents and ill health have huge social and economic implications on workers, their families and communities. Top mining top issues are respiratory diseases, noise, explosives, ventilation, fire, and explosion. However, one of the principal mechanisms for achieving Occupational Health and Safety (OHS) goals and mapping the future is government regulations of employers. In Nigeria, the situation is not different; mining operations are equally hazardous and have far reaching implications. In 1995 the Ministry for Solid Minerals was established to focus on the development of other categories of mineral products ranging from gold, coal, uranium, and tantalum deposited across the country. Prior to this an Act of Parliament Act Cap 121 of 1946, was in place to regulate amongst other contents mining safety. This was subsequently reviewed following the incidence of Lead poisoning resulting from small scale miners processing gold ore highly contaminated with lead in Zamfara state (northern Nigeria). Hundreds of children died as a result of exposure to lead poisoning, it was clear that the regulations were not sufficient (details to be discussed). However, advances have been achieved in mining engineering since then. A review team was constituted to provide a more stringent law to regulate mining operations in Nigeria. The strategies for mapping the future of OHS in mining engineering will employ amongst others setting and adopting ISO/ILO standards and enforcement; providing technical assistance; and establishing sustainable developmental structures as surveillance and compensation. The management systems approach was also developed as a result of cases of accidents. The accepted international standards guidelines and requirements will be proposed. Furthermore in mapping the future for Mining Engineering, it is suggested that most countries have their own management strategies and legislation to improve safety of workers through greater consistency and efficiency of OHS programs. Some American researchers came up with the Safety Engineering Model. The Australian Mining Council of mineral and petroleum resources after the Catastrophic Maura Disaster developed the National Mine and Safety Framework. In Canada, after the Hillcrest mine disaster in 1914, Allan shaft coal mine catastrophe in 1918, Westray mine explosion in 1992 and other disasters, Occupational Health and Safety Act R.R.O 1990 was sufficiently developed to provide adequate safety conditions and standards. In Nigeria after the disastrous Zamfara lead poisoning, which claimed the lives of hundreds of children due to exposure and lack of appropriate safety measures, stringent measures were developed by the federal ministry of Justice to address and regulate mining process in Nigeria.

Aug 1, 2013

By John S. Alexander

By J. Kretschmann, H. Mischo, O. Drusche, S. Krause

Mining is and will be inevitable in spite of the increasing implementation of circular strategies. The energy transition and population growth will boost the demand for critical raw materials. It is the opportunity for miners to reinvent their business models. Generating attractive new business cases with sustainability-oriented innovations meets investor and stakeholder expectations from the beginning. This contribution guides managers on their pathway towards sustainable success. Contextual sustainable business model patterns will be presented that can be adjusted individually, regardless of actor’s size. It will also point out, how sustainable value creation can be measured on business model level.

Feb 1, 2023

This summary of State laws on explosives wag compiled primarily to ascertain what subjects relating to their control have been acted upon by each State legislature and, in general, how they have been treated. It does not Include any legislation passed after 1942, or any proclamations, regulations, or administrative orders. It does not purport or attempt to be authoritative. If any problem arises involving interpretation of the statutes of any particular State, the original source must be consulted for the exact words used by the legislature. This summary, however, will be useful in determining whether relevant statutes exist, and in locating them quickly, with a minimum of effort. It will be of value also in comparing statutes in other States to determine what construction has been placed upon them by the courts of these jurisdictions or to contrast the varying provisions of many States upon a similar subject. To make these comparisons easier, the statutory provisions for each State have been grouped under several major topics in outline form. Although this sometimes has resulted in disruption of the continuity of individual acts, the increased general clarity and availability of comparable sections have more than justified the procedure followed.

Jan 1, 1943

By Ray Mason, Damien Label, Howard Bernier, Kevin McDermott, Kevin Coombs

"GeneralWabush Mines is an unincorporated joint venture of seven steel companies and Pickands Mather & Co. The mining and concentrating facilities are located in southwestern Labrador and the pelletizing and shiploading facilities are at Pointe Noire, 200 miles south, near the town of Sept-lies.The operation is based on a 5 ½ sq. mi. specular hematite deposit with a reserve of 375 million tons of concentrate. Annual production capacity is rated at 6 million tons of pellets per year. The final upgrading process utilizes high-tension separation of silica following wet autogenous grinding, spiral gravity separation and fluo-solids drying. The concentrate is railed in closed cars to Pointe Noire. The concentrate is reground dry and pelletized on Dravo Lurgi travelling grate machines to produce an oxide pellet with 65.5% Fe, 3.0% Si02, 1.95% Mn and 93.5% Tumble Index.HistoryPlant operations commenced in 1965 with a concentrator capacity of 5.3 million tons per year and a pelletizing capacity of 4.8 million tons per year. The original facilities for classifying the crude ore into fine and coarse fractions for storage purposes before reblending as autogenous mill feed were found to be unnecessary and were by-passed after plant startup. Capacity of the operation was increased to 6.0 million tons of pellets per year in 1968. This increased capacity required the installation of an additional160 cleaner spirals in the ore dressing plant, a new 5000 hp ball mill, three balling circuits and increased cooling air capacity in the pellet plant.In 1970, the regrind circuit in the pellet plant was converted to dry grinding and a significant reduction in grinding media consumption and maintenance costs was realized. A ninth grinding mill of 5000 hp capacity was installed to compensate for the reduced capacity in going from wet to dry grinding."

Jan 1, 2000

By Arthur H. Redfield

The expansion of city street laving which characterized the ten years ended December 31, 1929, according to a survey of 201 representative cities, made by the bureau of Mines, reached it climax in 1927, with decreases reported for 1928 and 1929. The upward trend, followed by a decline, was general in cities of all sizes included in this study, but was most pronounced in cities of 40,000 to 100,600 inhabitant and in the Northeastern, Southeastern, and Southwestern States. In the North-Central States the trend of paving; was downward from 1925 to 1929; in the Pacific, and Rocky Mountain States it was generally upward. Over the nation as a whole, bituminous types of paving continued to lead, furnishing two-thirds of the total street pavement laid in the 201 cities from 1925 to 1929. The actual yardage of bituminous pavement laid in these cities, however, was 3.8 per cent less in 1923-than in 1925, and the ratio of bituminous pavement to the total pavement t dropped from 70.4 per cent in 1925 to 62.1 per cent in 1928, rising to 65.1 per cent in 1929. The area paved with Portland-cement concrete amounted to only one-fourth of the total, pavement laid in these cities from 1925. to 1923., but the yardage of Portland-cement pavement increased by half during the period, and its share in the total pavement grew from 19.3 per cent in 1925 to 30.0 per cent in 1928, declining to 29.5 per cent in 1929. Brick, block, and stone pavements, which constituted the remaining one-twelfth of the total pavement laid in the 201 cities, decreased one-third in yardage, and declined in relative importance from 10.3 per cent in 1925 to 6.6 per cent in 1929.

Jan 1, 1931

By Wm .. O. Vanderburg

This paper describing the mining practices at the Block P mine of the St. Joseph Lead Co. at Hughesville , Mont . , is one of a series of similar papers being prepared by the Bureau of Mines on mining practices , methods , and costs in the various mines of the United States .

Mar 1, 1931