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By Leslie D. Marrus

This project and final report represent an effort to collect, analyze, and verify reliability and performance data on currently available medium -to-high seam models of continuous miners being used in underground coal mining. The analysis determined availability, mean time and tons between failures, amounts of down time associated with various failures, labor and part costs required to correct failures, and various indices of maintainability. Machine performance and reliability are discussed relative to cumulative tons (machine age) produced and production rates (machine loading). It was determined that performance can be significantly improved given preventive maintenance programs that will increase machine availability.

Jan 1, 1976

By Albert Ladd Colby

A GLANCE through the Bibliography appended to this paper will show that the Transactions of this Institute contain what virtually contitutes a history of the development of the manu¬facture of steel rails in this country and abroad. It is, therefore, fitting that this paper, bringing one branch of this important subject down to date, should be here presented, and it is also appropriate to select this joint meeting of our Society with the Iron and Steel Institute to compare the specifications covering the rails produced in these two countries, and to propose a standard specification to govern the manufacture of American rails for export. During the last ten years the production of Bessemer steel rails in the United States and Great Britain has amounted to 32,128,720 gross tons. Nearly 19,000,000 tons have been rolled in the past five years. The next five years will see an even larger output, owing partly to the extension of railway projects in the Orient, in South and Central America, in Mexico, and in Australia and the other British Colonies. Of late years, the American rail-mills have so largely increased their daily output, that trade conditions have often made possible the delivery of American rails to foreign ports. The tenders submitted by American mills, however, have always been accompanied by requests for changes in the foreign specifications, chiefly in the reduction of the amount of testing required; and it has only been natural, especially at first, that the engineer, whose specification had always been accepted without question by British mills, should interpret American tenders 'as an evidence that an inferior rail would be furnished

Sep 1, 1906

By E. M. Timoshenko, A. V. Tarasov

The results of laboratory, bench-scale and semi-commercial investigations of a method for adding surfactant (technical-grade lignosulphonate) to the process of pressure leaching of nickel-containing pyrrhotite concentrates have been discussed. Lt has been demonstrated that feeding of technical-grade lignosulphonate distributed along the length of an autoclave ensures a reduction in its requirement by a factor of 1.5 to 2 as compared with single-point feeding; it also results in a decrease by 5% in the unit requirement of metallized iron-bearing precipitator in the process of non-ferrous metals precipitation and reduces by 0.05 to 0.1% (abs.) the nickel and copper contents in the tailings of the given process. Technical solutions have been proposed for commercial introduction of the process.

Jan 1, 2004

By Pedro Lilienfeld

This Final Report describes a program whose objective was to design, develop, fabricate, and test an airborne mass monitor for unattended and recording measurements of the concentration of dust in mining environments. Sensing collection are performed by beta-radiation attenuation and inertial implementation respectively. The instrument is portable, battery or line operated provides a digital printout of the mass concentration during each selection sampling period, as well as the accumulated mass of dust, and the elapsed sampling time.

Jan 1, 1974

By Robert H. Ridgway

This paper presents the results of the second in the series of annual canvasses on the consumption of ferrous scrap and pig iron in the United States, inaugurated in 1935 by the Bureau of Mines and published in Report of Investigations 3329. The study was undertaken in response to requests from trade organizations and others for detailed statistics on this phase

Jan 1, 1937

By Robert H. Ridgway

This paper presents the results of the second in the series of annual canvasses on the consumption of ferrous scrap and pig iron in the United States, inaugurated in 1935 by the Bureau of Mines and published in Report of Investigations 3329. The study was undertaken in response to requests from trade organizations and others for detailed statistics on this phase of the iron and steel industry. Thus, for the first time, producers, buyers, sellers, and consumers of iron and steel scrap have had an accurate statistical picture of this important raw material As originally contemplated, the study was to be continued on an annual basis, but, owing to budgetary limitations for the fiscal year 1937-38, the Bureau may be unable to conduct the canvass for 1937.

Jan 1, 1937

This talk was delivered in Kalgoorlie in April this year, to the Kalgoorlie Branch of The Institution of Engineers, Australia. We believe it is of such interest to members of our Institute and readers of this publication we believe it important to extend the audience who have the opportunity to read it. An edited version follows:"Why should we be so concerned about Mining Related Education; after all is said and done, the mining industry is not a great employer of persons?"The mining industry is capital rather than labour intensive. It employs only 2.7 per cent of the national workforce. However; the minerals industry is Australia's major exporter accounting for over 40 per cent of the nation's total export of goods.In Western Australia the value of minerals production in 1985 was about $5,000 million and consequently mineral exports accounted for about 53 per cent of the total value of overseas exports from the State. The diversity of the mining industry is also worthy of mention and produces iron ore, alumina, gold, nickel and mineral sands. That apart, our potential to become a major producer of diamonds, rare earths and petroleum products is considerable, not to mention base metals (copper, lead and zinc) and uranium.Our mining industry is of national importance and contributes in excess of 30 per cent of the total value of Australian overseas trade. Although the mining ind ustry does not employ many people, the people it employs contribute very much more, per capita, to the wealth of the nation than do employees in any other sector of our economy.No-one would deny that during the 20th century Australians have depended on the export earnings from the sale of relatively unprocessed agricultural products and more recently the sale of relatively unprocessed minerals for their standard of living.Not surprisingly, therefore, our economy is highly vulnerable to unstable world commodity market prices.The slump in trade we are currently experiencing (in first quarter 1987-Edition) was brought about by the over supply of the raw materials we produce. However, the recent downturn in world market prices is more serious than previous slumps because in part it is due to technological advances 'in other countries which could have a permanent effect on the world trade of primary products.

Jan 1, 1987

By C. E. Gregory

In terms of a Research Proposals supported by a Grant Agreement dated 30 June 1973, the author was commissioned to prepare an annotated bibliography of mine fires. The main objective was to conduct a comprehensive program of library research and search of official files to prepare a list of articles dealing with actual occurrences of mine fires. This bibliography as now completed includes an annotated reference from each article or report cited, underlining the cause, extent, methods used, procedural errors made, results achieved, ventilation effects, and lessons learned from the operation of subduing the particular fire.

Jan 1, 1974

By Felix du Breuil

Contract H0177044 included three objectives; (1) consolidate, maintain, and distribute information on STE approved lighting systems; (2) develop and present one-day seminars on underground mine lighting; (3) determine direct labor and hardware costs associated with the installation of mine illumination systems. All objectives were completed with results as follows: Task I - A file containing 1350 Statements of Test and Evaluation (STE) for all types of underground equipment was developed and publicized throughout the coal fields, A total of 40 requests for STE information was received and processed. Task II and III - A series of 50 seminars was scheduled and presented to 942 attendees throughout the coal fields. The seminars were well received and attendees indicated the information presented would be helpful in bringing their equipment into compliance. Holding a series of seminars in the coal fields, instead of a few in population centers, was favored by attendees. Task IV - Installation cost data obtained on 415 lighting systems indicate that the factors which most affect installation costs are higher hardware cost for DC powered systems and slightly higher manpower requirements for systems installed underground. Based on these data, the total cost to industry of retrofitting existing underground equipment could range up to $50 million.

Jan 1, 1979

By C. A. Herbert

Coal-mine explosions in the United States during the past 10 years ranked third among the causes of coal-mine fatalities and constituted 16.1 percent of the total fatalities. In Indiana, however, during this same period the percentage of fatalities from this cause was much higher than the average percentage for the entire country. It is only through knowledge of the factors that have led to these past explosions that intelligent steps may be taken to prevent similar occurrences in the future. Although information concerning many of the earlier explosions is lacking, an attempt has been made to tabulate the information available in the hope that it may be of assistance in calling attention to some of the principal causes of explosions in Indiana.

Jan 1, 1934

During the first quarter of 1973 ADL worked closely with PMSRC staff, under an extremely compressed time schedule, on all aspects of the detailed planning, organization and overall coordination and preparation of the lectures and in-mine demonstrations for the Bureau's Technology Transfer Seminar on Mine Communications given in March of 1973 to representatives of the mining industry. Our efforts centered on the detailed organization and preparation of each of the five technical seminar lectures and associated supporting material, and the coordination of tasks assigned to ADL and other seminar participants. Revised and expanded drafts of the seminar papers were prepared from rough draft versions obtained from PMSRC, Collins Radio and ADL staff. Measurements were made to gather key data on the operation and performance of each of the following systems installed in the Bruceton Safety Research Mine; call alert paging, roof bolt paging, section wireless radio, and guided wireless radio systems. These data were analyzed, manufacturer's equipment specifications utilized, and calculations made to provide performance curves and data for each of the above systems. A substantial amount of artwork was conceived and prepared for 35 m slides, system identification posters in the mine, and seminar handouts. This artwork included some forty 8-1/2" x 11" line sketches, graphs, block diagrams, circuit diagrams, coverage maps, and other line drawings; five 30" x 40" block diagram system identification posters suitable for in-mine use; a 20" x 30" detail perspective illustration of a representative coal mine layout; forty viewgraphs; and seventy 35 m slides of the artwork and word charts. Conferences, discussions and review sessions were held with conference participants to help coordinate the various efforts, obtain technical information, and make final plans regarding the lecture presentations, associated visual aids, and the communication system installations to be demonstrated in the Bruceton mine. These meetings included final systems checkouts and dry run presentations and reviews of the lectures and mine demonstrations. This phase of the seminar effort concluded with R. Lagace and R. Spencer of ADL participating in two days of seminar presentations in the lecture hall and in the Bruceton mine.

Jan 1, 1974

By J. E. Shelton

Flotation tests are described on samples of two lowgrade nickeliferous ores of Oregon and Washington. The sample from the Congress mine, Ferry County, Wash., contained 1.2 percent Ni, occurring chiefly as millerite. The sample from the Shamrock mine, Jackson County, Oreg., contained 2.20 percent Ni and 0.78 percent Cu occurring chiefly as pentlandite, nickeliferous pyrrhotite, and chalcopyrite. The millerite in the Congress ore was concentrated by flotatioin with aulfydric collectors in a series of locked tests to recover 73 percent of the nickel as a 7 percent bulk concentrate. By successively regrinding and floating the bulk concentrate, it was further concentrated to 12.4 percent Ni at a recovery of 59 percent and 21.8 percent Ni at a recovery of 50 percent. Attempts at selective concentration of the copper-nickel Shamrock ore were only partly successful because of the intimate association of pentlandite and chalcopyrite. The nickel concentrate, which contained 86 percent of the nickel, had an analysis of 4.42 percent Ni and 1.03 percent Cu. The copper concentrate had an analysis of 18.8 percent Cu and 1.96 percent Ni and contained 48.5 percent of the copper. A bulk sulfide concentrate contained 92 percent of the copper and 01 per¬cent of the nickel and had an analysis of 4.17 percent Ni and 1.63 percent Cu.

Jan 1, 1956

By I. Anazia

Selective fatty acid flotation of carbonate gangue from sedimentary apatites was achieved under acidic pH's without a specific apatite depressant and without conditioning the pulp with the collector. Concentrates (35-38% P205, 0.8-1% MgO) with high recoveries (80-85%) were produced from Indian and Chinese dolomitic ores. The calcareous and/or dolomitic-siliceous phosphate ores of South Florida and Utah required two flotation stages: one for carbonate removal, as mentioned above, and the other for phosphate recovery from siliceous gangue. Preliminary tests on the South Florida ore gave concentrates analyzing 29% P205 and 0.8% MgO with a P205 recovery of 76%. Data are also included showing the applicability of the process to the dolomitic-calcareous-siliceous Western U.S. phosphate ore from Utah. A concentrate obtained from this ore assayed 30% P205 and about 1% MaO.

Jan 1, 1987

By Marek Dworzanowski

Dense medium separation (DMS) is critical to the operation of coal and diamond beneficiation plants. It is also utilised in iron ore, manganese, chromite and andalusite beneficiation as well as pre-concentration for platinum-bearing UG2 ore. Gravity concentration plays an important role in the processing of diamonds, coal, gold, platinum, titanium minerals, zircon, chromite, iron ore and manganese. The DMS and Gravity Concentration operations and technology in South Africa conference will focus on the operation of DMS and Gravity Concentration circuits in the South African Mining Industry. The current status of the technologies and equipment employed will be presented as well as future developments. The conference was set up to showcase South African DMS and Gravity Concentration operations and provide a forum where operators, technology and equipment suppliers can engage in knowledge sharing. The papers cover a wide spectrum of topics, including descriptions of operations, optimisation projects, new capital projects, equipment applications, process monitoring and process selection. Most commodities and unit processes associated with DMS and Gravity Concentration are covered. The conference venue was selected to be the CSIR Convention Centre in Pretoria. The CSIR has contributed to DMS research in South Africa and it is located not far from many coal, diamond, gold, platinum and chrome mines that extensively utilise DMS and Gravity Concentration in their beneficiation plants. I believe that the papers and presentations submitted for this conference will provide a valuable future reference for DMS and Gravity Concentration, thus making the work of all the contributors to this conference highly rewarding and worthwhile.

Jan 1, 2006

By John D. Sullivan

The recovery of copper by leaching from relatively low grade ores containing both oxidized and sulphide minerals is rapidly gaining in commercial importance. There is an economic limit below which certain ores can not be treated by concentration methods, and material with values below this limit must be discarded, possibly to be treated later, or the copper must be extracted by wet processes. Heap leaching has been carried out by the Phelps Dodge Corporation, Copper Queen Branch, for several years, and to-day its plant is a large producing unit. The Ohio Copper Coy at Bingham, Utah; has been leaching in place since 1919. Many other leaching operations are also being; carried out in various parts of the United States and in foreign countries. The plant at Rio Tinto, Spain, may be considered the father of heap leaching.

Jan 1, 1931

By Subhash Bhagwat

The definition of high sulfur coal varies from plant to plant and is subject to changes over time as the environmental regulations change. In plants constructed after September 1978 hardly any domestic coal can currently be burned without the use of Flue Gas Desulfurization (FGD) because a 70 percent reduction in potential S02 emission is mandatory even when the potential emission is less than 0.6 lbs. S02/106 Btu heat input. On the other hand older power plants may in many cases be legally emitting up to 6 lbs. S02/106 Btu or more under some State Implementation Plans (SIP). The Clean Air Act requires, however, that in the long run all stationary sources of S02 pollution must abide by the ceiling of 1.2 lbs S02/10 Btu heat input.. Coals with a potential to exceed this limit must, therefore, be considered as high sulfur coals. Such a definition would be unrealistic because many SIP's aim at an emission level of 1.8 to 2.0 lbs. SO2/106 Btu for existing plants and a stricter limit does not appear to be enforceable in the next 5 to 10 years. As a result, coals with an emission potential of greater than 2.0 lbs of S02 per 10 Btu heat input are considered high sulfur coals for the purpose of this investigation. Based on this definition and the 1984 actual consumption of coals by U.S. electric utilities (table 1) only 7 out of the 24 coal producing states could be categorized as low sulfur states. The actual S02 pollution, however, depends on total tonnage of a type of coal as well as the sulfur content of the coal. Table 1 also indicates that only 6 states--Kentucky, Illinois, West Virginia, Ohio, Pennsylvania and Indiana-account for nearly 77 percent of S02 pollution potential in the United States. These 6 states have therefore been chosen for this investigation.

Jan 1, 1986

Consumption and intensity of use trends for twelve metals, by industrial end use, were estimated for 1972 through 198Z. The trends were then forecast through 1993 using standard statistical methods. The intensity of use measure selected is the quantity of metal consumed per constant dollar output of a specific industrial sector. The metals studied were aluminum, chromium, cobalt, copper, lead, manganese, nickel, the platinum-group metals, tin, titanium, tungsten, and zinc. Average annual growth rates for the following four of the twelve metal increased from 1972-82 as follows: aluminum, 1.00 percent; platinum-group metals (consisting of platinum, palladium, and iridium), 8.83 percent; titanium, 7.82 percent; and tungsten, 6.09 percent. Consumption. for the remaining eight metals decreased at average annual rates ranging from 0.58 percent (copper) to 5.37 percent (manganese).

Jan 1, 1986

By J. Cseff

A variety of shaft and hoist equipment exists in the United States. Nearly all hoist systems are electrically driven. Machine elements which comprise the hoists and ancilliary equipment include bearings, shafting, drums, gear reducers, couplings, brakes, clutches, sheaves and electrical motors. Volume I, Systems Description, describes the various components encountered in most mine hoist and shaft installations, and brief descriptions of functions and constructions. Hoist ropes and balance ropes are specifically excluded from this report. Associated with the hoisting system is the headgear, shaft and equipment, loading/dumping facilities and the actual conveyances and their rope attachments. Volume II, Inspection and Maintenance Procedures, discusses scheduled Inspection and preventative maintenance in general terms. Preventive scheduled inspection and maintenance procedures assist in the smooth operation of mine hoisting plant, by the prevention of unscheduled or catastrophic equipment failure and its attendant downtime. Schedules and overall maintenance planning is required at the management level. Records and equipment logs must record inspection and maintenance, and unusual operations or incidents. A cross reference between MSHA regulations and various equipment components is included as part of the report. A discussion of the various non-destructive testing methods which may be applied to hoisting equipment is also included.

Jan 1, 1981

By K. Terhaar, K. Prisbrey

The objective was to determine operating protocols for a lead and silver column flotation cleaner, being considered for installation at Sunshine Mining & Refining Co.’s Kellogg mill in Northern Idaho. In this column, tetrahedrite and galena were floated, and pyrite and other gangue minerals, including siderite and silica, were depressed. The procedure was to develop a dynamic simulation using a linear transfer function approach. The transfer function related cause and effect variables such as the influence of collector and depressant dosages on recovery and grades. Bench-scale flotation tests followed by pilot column testing provided the data used to develop a linear transfer function. The transfer function was derived using a spreadsheet. This model was applied to simulate how the flotation column could be made to respond to disturbances in feedgrade. The results were that xanthate, zinc sulfate, and sodium cyanide were found to be suitable controls for grade and recovery. Simulations showed the best sequence of manipulations of these reagents, and these sequences were useful for future operator training. The conclusion was that linear transfer functions were able to simulate lead and silver recovery, develop scenarios for operator training, and provide a foundation for future on-line control.

Jan 1, 1999

By W. W. Adams, T. D. Lawrence

"Despite the manpower shortage and other difficulties of operation in war time, the National Safety Competition of 1943 for the promotion of safety in the mineral industries of the United States was notable for having a larger enrollment of mines and quarries than in any other year except 1941 and 1942 since the yearly safety contests were inaugurated in 1925. The competition was also notable for having a larger number of man-hours represented by the competing companies than in any previous contest except that of 1942. The ratio of accidents and days of disability resulting from accidents to the number of man-hours of work performed was more favorable than in 1942; the accident-frequency rate was lower and therefore better than in 13 of the 19 years during which the annual safety competitions have been conducted, and the accident-severity rate was better than in 16 of the 19 years.The National Safety Competition is a yearly safety contest conducted by the Bureau of Mines, United States Department of the Interior. Companies that win first place in their respective group in the contest are awarded a bronze trophy, ""The Sentinels of Safety,"" which is provided by THE EXPLOSIVES ENGINEER magazine. Competing companies are segregated into six groups: Underground bituminous-coal mines, underground anthracite mines (in Pennsylvania), underground metal mines, underground nonmetallic-mineral mines, open-cut mines (without regard to kind of mineral produced), and open quarries (without regard to kind of stone produced). The bronze trophies are retained by the six winning companies for 1 year and are then transferred to the winners of the succeeding year's contest. On the pedestal of each trophy is engraved the names of the winners of the trophy. With the award of the trophies for 1943, therefore, the pedestal of each trophy bears the names of 19 winners."

Aug 1, 1944