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By P A. Tilyard

There have been enormous changes in mineral processing in the past four decades. For example grinding mill power has increased by an order of magnitude, regrinding is done to -10 microns and flotation machines are 100 times bigger. Operating staff have unprecedented opportunities for online monitoring and performance control of mineral processing plants. Sophisticated instruments can provide a plethora of data characterising the mineralogy and surfaces of particles. Digital computers allow complex calculations on huge amounts of data including modelling and simulation of machine and plant performance. However, all these changes have not necessarily lead to better metallurgical results. An analogy can be drawn with the thoroughbred racing industry in Australia. Significant advances in scientific knowledge in animal genetics, physiology, biomechanics and nutrition applied to the business have resulted in only a two per cent reduction in winning times for the Melbourne Cup and Caulfield Cup since the 1920s. A critical look at some mineral processing metrics suggests similar failures to improve performance despite putting in more resources. In fact certain parameters such as operating times and plant start-up performance are considered to have remained static or even deteriorated. There has been an emphasis on 'process' at the expense of 'outcomes'. The industry's strength has been in finding technical (or 'hardware') solutions while its weakness has been at the people end of the business in maximising and consolidating the gains from the technologies. Some trends in plant design over these years have exacerbated the apparent deskilling of operating and technical staff. Despite unparalleled options for communications, some staff are embarrassingly uninformed about technical developments in their fields. The 'boom and bust' cycles of the industry, together with trends in tertiary education and the effects of fly-in, fly-out (FIFO) operations, raise serious questions about the sustainability of human capital in the mineral processing sector. This paper by two experienced mineral processing engineers, with contributions from other senior practitioners, reviews these trends. While there may be an element of 'the older we are, the better we were', it is an attempt to identify the issues and propose solutions.

Jan 1, 2009

By Hazel J. Stratton

IN THE HALF-CENTURY that has passed since the Bureau of Mines was established in July 1910, the research and technologic investigations conducted by the Bureau's scientists, engineers, and other personnel have helped significantly in improving health and safety in the mineral industries and have contributed substantially in conserving the Nation's mineral resources through improved techniques in the mining, treatment, and use of mineral commodities. From Bureau laboratories have come new materials for industry and better methods of extracting and processing minerals and mineral fuels. Bureau safety investigations-complemented by equipment testing and by programs of mine inspection and education-have brought about safer and more healthful working conditions.

Jan 1, 1960

By SME SME

NORTH AMERICAN TUNNELING 2024 PROCEEDINGS

Jun 23, 2024

By Norman] [Seldle

This report describes the development of a mine machinery training system from initial conception through a task and skill analysis, a training system analysis, implementation of a prototype system, and initial validation of the prototype system. The objectives of the training are to improve safety and productivity simultaneously via complete, thorough training. A task and skill analysts was executed for shuttle cars, continuous miners, cutters, loaders, face drills, tractors, and scoops. The prototype training system is for shuttle car operator training.

Jan 1, 1976

The first metal-mine accident-prevention course was prepared and published in 1942-45 as a series of seven miners' Circular (Nos. 51-57). The scope of the course has been broadened, revised, and brought up to date and is being published as a similar series of seven miners' circular pros. 51-57, revised) on accident prevention in metal and nonmetallic mines. These circulars are: Accident Statistics (Miners' Circular 51), dealing with general statistics on accidents and injuries at metal and nonmetallic mines, including causes, costs, and the uses of investigations and reports of all accidents.

Jan 1, 1957

By G. E. Cole

"Amongst the mineral products of Canada gold holds the second place in value of yearly output. . . . . .The production of gold has increased steadily during the past six years and has somewhat more than doubled in that time. For the past four years Canada has been third among the gold producing countries of the world, surpassed only by the Union of South Africa, and the United States of America," and now yields somewhat more than 9 per cent of the annual output of the world."-"The Gold Situation in Canada". Bulletin of Development Branch, Canadian Pacific Railway. The history of gold mining in Canada is comparatively modern and does not take one further back than the late 'fifties of the 19th century. If the efforts of the early explorers in Canada were expended in "seeking with equal ardour, proselytes and gold", history fails of any record of their success in the search for the precious metal. As early as 1849 not a few Canadians travelled from the east by land and water to the Californian goldfields. In the then settled part of Canadathe east-people were alive to the value of any mineral discovery; but the west, owing to its remoteness and to there being no ready means of communication, was virtually isolated from the east.

Jan 1, 1927

By Walter W. Kaufman

The braking performance of underground, rubber-tired, non-coal mining vehicles is evaluated. Surveys of mining equipment and braking manufacturers and underground stopping tests are discussed as they relate to this evaluation. Stopping performance recommendations are included as well as related aspects of roadway construction and runaway vehicle protective devices.

Jan 1, 1977

By L. D. Schmidt, W. C. Schroeder, A. C. Fieldner

"INTRODUCTION The highly mechanized character of modern warfare makes steel the most vital raw material. The shortage of steel scrap in the United States is forcing the use of increased quantities of pig iron in steel manufacture, so that the rate of pig-iron output will continue to be the controlling factor in steel production. 5/ At the same time, the construction of new blast furnaces is limited both by time and the amount of strategic material available. Under such circumstances, every effort must be made to attain and then maintain maximum pig-iron output from the equipment now in use.When forcing a blast furnace to the ultimate in production the highest standards for quality and uniformity of the coke must be maintained. In view of these facts, the Bureau of Mines, in cooperation with the Office of the Solid Fuels Coordinator for War, is surveying the coke industry to study the various steps in producing coke of higher quality and greater uniformity. 6/ The engineers conducting the survey are visiting key men in coke-oven and blast-furnace organizations to determine, first, the major and most common problems in coke production and use; and, second, the best and quickest method for solving them. Various operators have made good progress in solving individual problems, and a Nation-wide exchange of information among them will make possible widespread adoption of the best practices. It is the purpose, of the survey and reports such as this preliminary one to facilitate such exchange of information. As an outgrowth of the survey, it was soon revealed that many operators could be helped by cooperation with various Government agencies, particularly to procure suitable coals, minor additions to equipment facilities, and tests on certain properties of coal or coke, or specific advice concerning the operation of various types of equipment. The machinery and organization necessary for securing this cooperation have been set up as a part of this work."

May 1, 1943

By R. E. Gray

[The purpose of the study is to investigate cases of subsidence over abandoned mined-out areas of the Pittsburgh Coal identified from published and unpublished sources and to determine through a consideration of the geology, topography, climate, mining activity, and evidence at ground surface, what mechanisms control subsidence .and under what circumstances it takes place. The study wan performed it two phases, the first to identify all documented incidents of subsidence in mined-out areas of the Pittsburgh coal Region; and the second, to study a particular portion of the region in detail, collecting pertinent data relative to the sites within, characterizing roil the nature of the subsidence and its economic consequences, and determining the applicability of the findings to other areas whore similar problems with the collapse of abandoned miner have been encountered.]

Jan 1, 1977

By F. D. Everett

This report, based on information made available by four uranium-producing companies, describes the geology, exploration, open-pit development and mining, and shaft sinking in the Gas Hills uranium district of Wyoming. Open-pit stripping features motor-scrapers push-loaded by crawler or rubber-tired tractors. The ground generally can be ripped, and little blasting is necessary. Detailed data are given on grouting for ground stabilization in sinking a small-diameter shaft in the relatively unconsolidated sandstone and siltstone, Cost and performance data are presented as made available by the companies.

Jan 1, 1963

By F. D. Everett

This report, based on information made available by four uranium-producing companies, describes the geology, exploration, open-pit development and mining, and shaft sinking in the Gas Hills uranium district of Wyoming. Open-pit stripping features motor-scrapers push-loaded by crawler or rubber-tired tractors. The ground generally can be ripped, and little blasting is necessary. Detailed data are given on grouting for ground stabilization in sinking a small-diameter shaft in the relatively unconsolidated sandstone and siltstone, Cost and performance data are presented as made available by the companies.

Jan 1, 1963

By William O. Vanderburg

This paper 3/gives the results of a reconnaissance of mining districts in Clark County, Nev., made from November 18 to December 22, 1936, and from February 9 to March 8, 1937-in all, 63 days. While the field work Was being done, virtually all of the mining districts in the county were visited and many data on active and inactive properties were obtained. The report covers the locations of the various mining districts, the nature of the deposits, information on past operations, current activity, and general data likely to be useful to operators, investors, and others interested in mining. The geology of the deposits is discussed only briefly. The principal metal-mining districts in the county are Goodsprings, Eldorado, and Searchlight. The zinc-lead ores of Goodsprings have been the most important economically, followed by the gold-silver ores of Eldorado and Searchlight. In the industrial-mineral field, gypsum, limestone, silica sand, and borates are the principal products. Metal mining in the county is characterized by numerous small operations and the ores are either milled locally or shipped to distant smelters.

Jan 1, 1937

By Walter W. Kaufman

The braking performance of underground, rubber-tired, coal mining vehicles is evaluated. Surveys of mining equipment and braking manufacturers and underground stopping tests are discussed as they relate to this evaluation. Stopping performance recommendations are proposed.

Jan 1, 1977

By W. L. Saunders

(Wilkes-Barre Meeting, June, 1911.) I. INTRODUCTION. IT is now generally admitted by experts that at least so far as rapid progress is concerned the Alpine system of tunnel-driving is superior to any other. This is perhaps natural in view of the record of experience in driving tunnels through the Alps. These great mountain-chains cannot be treated in the ordinary way by shaft-sinking and driving headings, thus multiplying the points of attack. The work must be done from the ends only, hence speed in driving is of the utmost importance; and, as necessity is the mother of invention, the concentration of effort to make progress has resulted in an organization and in mechanical appliances that have produced results so much in excess of the usual practice, even in America, that a discussion of the subject in detail should be of much value to the engineer and contractor. The first Alpine tunnel was the Mont Cenis, length 7.5 miles, driven with a progress that averaged about 7.75 ft. per day. Next came the Saint Gothard, 9.5 miles long, 18 ft. per day; Arlberg, 6.5 miles long, 27.25 ft. per day; Simplon, 12.25 miles long, 36 ft. per day. The figures represent progress when driving from two headings, so that by dividing them in two we get the daily single-heading progress. The latest of the Alpine tunnels is the Loetschberg, now being driven. In this work the world's record has been beaten by a single day's record in one heading of 36 ft. and by an average daily record in. one heading of 29.5 feet. The Alpine range forms a natural barrier between a large section of northern and southern Europe. This range extends from the southeast of France to the frontier of Hungary, between Italy and the plains of southern Germany. The contour

Jul 1, 1911

By P. S. Haury

"INTRODUCTION Many ore deposits were discovered in the Wallapai Mining District, which covers the Cerbat Range in Mohave County, Ariz., during the early period of mining there from about 1865 to the 1890's. A considerable amount of production was obtained from shallow lead carbonate ores that carried considerable gold and silver.Mining was revived in 1906 and again during the First World War, and soma of the mines were deepened into the underlying sulfide zone. Substantial quantities of metal were recovered from two mines, the Golconda and the Tennessee-Schuylkill, that were, developed to depths of 1,600 and 1,400 feet, respectively. The Golconda is credited with $6,500,000 gross productions. 2/ This mine was not operated after 1917. The Tennessee-Schuylkill is still operating after a yield of about 300,000 tons of ore that averaged 4.33 percent lead and 7.74 percent zinc and contained an appreciable amount of gold and silver.Many of the old mines were reopened in 1942 or 1943 under the stimulus of premium prices for lead and zinc. A large proportion of this work was finished with loans from the Reconstruction Finance Corporation. It was believed that a good deal of lead and zinc could be recovered from the mines if a custom mill for concentration of the ores was available locally."

Aug 1, 1947

By GLENVILTE A. COLLINS

(Presented at a Meeting of the Spokane Local Section of the Institute, Feb. 17, 1912, and accepted for publication in the Bulletin. ) WHILE I am not at the present time engaged in active mine-management, my duties permit of extensive study and examination of many mines, mills, and reduction-works in various places throughout the United States. Being much interested in efficiency-work in general, and an ardent reader of writings on this subject by Frederick W. Taylor and others, as applied to manufacturing-plants, and having served my apprenticeship from mucking to the engineering design of ore-dressing and underground plants, I hope that this paper will lead others to investigate the field more fully, to the improvement of general mine- and mill-operations, as well as the advancement, intellectually, physically, and financially, of the employee and his relations with the employer. If a man who is prepared to look closely and observe broadly starts in Canada and zig-zags from camp to camp to southern Mexico, taking time casually to inspect mines, mills, and smelters, he will be pitifully impressed by the great difference in customs, and the general waste of labor, time, and money throughout the country. He will so seldom observe a dollar's worth of results given in exchange for a dollar spent that he will form a poor opinion of operating-efficiency and management. This highly-scientific department, requiring an amount of skill and executive ability equaled in few, if any, of the professions, certainly falls short of the standard established in our greater manufacturing industries. It is easily said that this is due to the diversity of conditions in mining, milling, and smelting. But on second view it must be admitted that there is room for tremendous improvements in nearly every mining-organization. The proposal of such improvements is often met by the argument that any mine

Sep 1, 1912

Jan 1, 1925

By Gordon E. Green

This report addresses remote monitoring of coal waste impoundments for stability. Existing automated geotechnical monitoring systems are described and reviewed along with details of instruments suitable for such systems. An impoundment in West Virginia which was in the construction stage was instrumented and monitored between July 1979 and may 1981. Sensors which measure surface and subsurface parameters including settlement, horizontal deflection, surface tilt, pore water pressure, seepage, pond level, and meteorological parameters were installed. Data from the 37 sensors were collected by on-site logger and transmitted by telephone to a central processing station in Seattle for recording and interpretation. Difficulties were encountered with telephone and powerline outages and malfunction of electronic units. Detailed descriptions of the design and performance of the system are provided along with evaluation and comparison with other systems. Recommendations for improving and expanding the capabilities of the monitoring system are given.

Jan 1, 1982

By C. S. Harloff, Frank R. Corwin

THE Nichols Copper Co., associated with the Phelps Dodge Corp. and the Calumet & Arizona Mining Co., has constructed at El Paso, Tex., and is now operating a copper refinery with a yearly capacity of 100,000 tons of anodes. Transportation facilities were perhaps the most important of the considerations that led to the selection of this site. The rapid industrial development of the Middle and Far West has increased the consumption of copper there. The advantage of local refining as against shipping the copper to the Atlantic sea- board is apparent. Copper refined in the Southwest is equally competitive for export shipment, either from the Gulf or the Pacific Coast ports. The tonnage of copper produced in the Southwest not only justifies the construction of this plant, but may warrant considerable expansion in years to come.

Jan 1, 1930

By Carlie E. Banks

Tasks during Phase I of this contract effort were performed in four principal functional areas. These were geology, hydrology, reclamation and mining. Data were gathered from literature reviews, mine visits, survey of manufacturers, consultation with government agencies, and unpublished or private communications with contractors and consultants. The data collected were analyzed for omissions or inaccuracies, then organized into tables, graphs and flow charts to provide a concise body of technical and cost data suitable for the engineering analyses required in Phase II of this contract. Maps illustrating estimated grade and thickness of the oil shale were prepared, some of which are included as exhibits to this report. A preliminary mine layout was performed to test the completeness of the collected data.

Jan 1, 1975