Search Documents

By R. B. Lawrie

Diesel powered underground mining equipment is presently the most productive, safest and efficient equipment used in underground mining operations. The widespread application of this equipment to underground mining is restricted, however, largely because of the difficulty of controlling the diesel engine exhaust emissions. This paper briefly examines control devices currently available for underground application, and also discusses the theory and mechanics of controlling diesel missions with particulate traps and filters.

Jan 1, 1985

By T. E. Kobrick

When Ralph Banks called and asked if I would agree to present a paper on environmental health in the coal industry, I was reluctant because I have not been actively involved in coal mine dust control on a day-to-day basis for a number of years. Ralph reminded me that I am one of the few industry people with an industrial health background who remembers the pre-1969 Federal Coal Mine Health and Safety era. This marks the second time within the past year that I have had a similar request based on the same basic reasons. While I was pleased to have been remembered, I'm beginning to feel like the football player who has played one too many games. In responding to Ralph's request to present an overview of the past, present and future of environmental health in the coal industry, I have attempted to take the broad approach of someone who, having been intimately involved in an area of endeavor for a number of years and then leaves, has an opportunity to revisit that area at a later date to see what has changed and what remains the same, what have been the successes and the failures. Since none of us can foresee the future, trying to project too far ahead is fraught with frivolity, except that unless one is foolish enough to accept a future invitation to review those predictions compared to actual events, no one will recall how accurate or inaccurate those projections might have been. I can assure you that I will not ask to accept that challenge, so you can rest comfortably that five years from today you will not be asked to sit through a similar presentation by me - and that's a promise.

Jan 1, 1985

By William C. Peters

"A large proportion of the earth's surface is blanketed by young sedimentary formations and by recent lava flows. How many Guanajuatos lie concealed beneath the rhyolitic capping of the Sierra Madre of Mexico? How many Kirkland Lakes are under the drift cover of the Canadian Shield? How many Wilunas are still hidden by the alluvium of the desert of Western Australia? How many ore deposits lurk underneath the basalt-covered plateaus of the Columbia River region? If erosion at Goldfield, Nevada, had stopped 100 feet higher, probably no ore would have been exposed. How many Goldfields are still awaiting discovery?" --Hugh Exton McKinstry, 1948

Jan 1, 1969

By Adolf U. Honkala

Dundee Cement Company was incorporated in 1958. The equity capital for the venture was supplied by a Swiss firm called Holderbank Financier and a group of its principals. Holderbank Financier, a holding company, is a direct outgrowth of Holderbank Cement Company, a company founded in 1912 by the father of Dr Hans Gygi who is the president of Dundee Cement Company and a member of the Board of Holderbank Financier. From one plant in 1912 located in Zurich, Switzerland, Holderbank grew to its present size of 32 plants in 17 countries, having a capacity of 90 million barrels of cement per year. Dundee Cement Company constructed its first cement plant near the little town of Dundee, Michigan. This site was selected because there is an abundance of limestone and clay of the correct chemical composition for cement manufacture and the deposit was advantageously located near the large population centers of Detroit, Toledo, Cleveland, and Chicago. Construction of the 5. 5 million barrel, two kiln, plant was completed and the plant started up in the fall of 1959. After a year or two of the usual problems in a new plant and the expected difficulty of breaking into a nearly saturated market, Dundee began to prosper.

Jan 1, 1970

By Thomas V. Falkie

Of the various critics of federal energy and minerals policy we are hearing these days--and they are legion--few make their points more vividly than our fellow SME member and eloquent spokesman for the mineral industry. Mr. Eugene Guccione. In a moment of comparative mellowness. Mr. Guccione recently characterized Washington's time-honored legislative and bureaucratic machinery as a case of "...scientific illiterates asking the incompetents to do the unnecessary." I hope the prevailing industry view of government is not quite that harsh, and yet one cannot deny that government intervention is indeed pressing in on the mineral industry with increasing force. What is happening today in Washington and in state capitols will have enormous impact--both short and long term--on the future of coal and mineral production in the United States. Symptoms of this trend are everywhere. In the first place, there is a sentiment, widely held and still spreading, that the government must become involved-- that no matter what the problem, the solution lies in more government intervention. Free enterprise versus statist, reflex reaction organizations. When it cones to regulation in the resource field, there is too often a tendency to start out by assuming guilt on the part of the mineral industry. This can lead to laws governing mineral recovery that are more punitive than constructive...laws drawn up with little research into the scientific or economic considerations involved.

Jan 1, 1975

By Robert H. Oliver

Flowsheet flexibility in new 750 TPH coal cleaning plant provides three unusual capabilities. Two compartment drum coarse H.M. washer can be adapted to provide two stage separation. Coarse section of plant can be operated without fine section when washing surface mined coal. Fine section can operate with flotation cells bypassed if strip coal oxidation kills the froth. Plant can be fed by belt from bulk storage, front end loader from storage piles and truck from the mines. Raw coal and each of four washed products can be fed by belts to three separate loading points on two separate railroads.

Jan 1, 1979

By Allan Gebhard

The purpose of this paper is to summarize the role of water resource monitoring in mining activities and to discuss the considerations that go into designing and implementing a monitoring program. The design of a monitoring program is invariably based on sound engineering and scientific judgement since no design formulas exist that can be universlly applied to the monitoring of all activities. As discussed in this paper, however, a methodology of designing a water resource monitoring program does exist. In order to cost-effectively monitor the water resource impacts of mining activities, the following three monitoring related items should be understood: 1. the role of water resource monitoring in the planning, construction, and operational stages of mine development, 2. the available water resources monitoring methods and the proper role of each method in the various scages of mine development, and 3. the strategies that should be followed in designing and implementing a water resource monitoring program.

Jan 1, 1976

By Jorgen Elbrond

Shovels, trucks and repair bays for the trucks each play their role in the capacity of an open pit operation. It is therefore convenient to have a procedure for the capacity calculation which takes all 3 factors into consideration in a comprehensive manner. This can be done by means of a cycle model, earlier developed for the shovel-dumper circuits, when the repair facility with its number of repair bays is added as a superimposed service system, which the trucks visit at certain specified intervals. The calculation model transforms the mechanical availability of the trucks into their operational availability. The system's capacity in truckloads per shift and the trucks' operational availability of certain combinations of shovels, trucks and repair bays are shown.

Jan 1, 1981

By Mehmet Guney

[The Atlantis-II-Deep is a hydrothermal mineralization located along the median valley of the Red Sea at a water depth of about 2200 m. Extensive exploration of the metal-rich brine deep revealed a potentially mineable deposit on economic interest consisting of oxides, silicates and sulphides with considerable concentrations of zinc, copper, cadmium and silver. Geostatistics was applied to assess the most likely in-situ vague of the metal potential for economical exploitation. Semi-variograms were constructed to characterize the structure of the regionalized distribution of the geological parameters. Volume grades and thicknesses were determined by the kriging technique, avoiding systematically biased high or low grades, and then block .tonnages were computed. The estimation variances, distribution of errors and histograms of observed and kriged values in each grid Mock were also produced.]

Jan 1, 1983

By Charles W. Merrill

The price records of 7 representative mineral commodities for the 68-year period 1890 through 1957 have been compiled and analyzed for significant trends. When reduced to real prices in terms of dollars of constant purchasing power or to the purchasing power of industrial wages at average rates, a substantial overall fall in prices is revealed. This downtrend contradicts the widely held concept that, heavy drafts on a mineral resource must lead to scarcity, reflected in rising prices. Three metals (aluminum, copper, and pig iron), two fuels (bituminous coal and petroleum)', and two nonmetals (sulfur and cement) have been chosen because of their preeminence in their respective categories, their significance in an industrial economy, and the ready availability of their price records. It might be added that these seven commodities. were selected before any price figures were compiled, none was selected or rejected to substantiate any preconceived notions as to price trends, The overall importance of the seven is demonstrated by the fact that, taken together, they composed over three-fourths of the value of all minerals produced in the United States in 1957. The first step in the analysis was to reduce the price records to a basis for significant comparisons, Two such comparisons have been made: (1) The quantities of each of the commodities that could have been purchased for an average hour's wage in each year; and (2) the unit price of each commodity through hhe years in terms of deflated dollars. These data are set forth in the accompanying table and two charts.

Jan 1, 1959

By Kirk Carlton

This paper deals with a group of subjects so familiar to all of us that we might question the need for discussion. Even so, nearly every day's business turns up expensive examples of differences in understanding, misdirected assumptions and incomplete technical purchase documents. As our international activities increase, so do these problem areas. Their expense in both money and embarrassment gives rise to this attempt to focus a little extra attention on technical criteria and specifications. The two terms ?criteria? and "specifications" are, we believe, worth separating with respect to meaning. They should not be used interchangeably, although they often are. Criteria are by definition "standards for judging", whereas specifications are "enumerations of particulars". In relation to plant or project engineering, the criteria are the general rules and data which apply to the whole project and the specifications are the further listing of detailed requirements for specific contractual items or pieces of equipment. We'll look a little more closely at specifications after we give another minute or two to this "criteria" subject,

Jan 1, 1973

By F. L. Pierson

Since the discovery of 'potash in the Carlsbad area in 1926 and the start of mining operations in 1931, "first mining," operations have been carried on. This is a room and pillar system in which approximately 62% of the total ore is removed. Or the basis of ore reserves and rates of extraction, the life of the mine in the early; days was estimated to be well over 50 years, however, even with an increase by additional ore reserves, it became increasingly apparent that the life of the mine was being shortened considerably by increased production. Further cause for the shortening of mine life was due to the exceptionally weak back over the northeast quadrant of the main orebody which had .caved in on first mining up to a height of 8 feet. Thus, in 1953 the decision was' made to begin pillar pulling, also called, second mining or final mining, and in December of 1953 this program was started after much discussion.

Jan 1, 1965

By Paul Soros

The rationale for innovations in two directions is identified: raising capital and annual throughput, in order to avoid the cost of constructing and operating an additional system and to reduce the capital cost of pits and tunnels, applicable to installations of any capacity. Cast histories cover railroad unloading of bottom dump cars, rotary dumping of random cars, with and without indexer, and unit trains as well as truck unloading of multiple grades of coal.

Jan 1, 1985

By M. Misra

The dispersion of oily collector has significant effect on the flotation recovery of ultrafine coal. Generally, reagent dispersion is accomplished by mechanical mixing and/or ultrasonic agitation, followed by direct addition of dispersed collector into the flotation cell. However, such dispersion and reagent addition techniques are invariably inadequate and non-selective. A new collector utilization technique involving gas phase transport of atomized collector has shown improved results when compared to conventional reagent addition techniques. This new technique involves atomization of the collector into the gas stream. Under these circumstances an aerosol is introduced into the flotation cell. Initially, the oil is dispersed within the gas phase (continuous with respect to oil) and the gas phase is dispersed within the pulp (continuous with respect to aerosol). In the flotation cell, the atomized oil droplets coalesce on the bubble's surface and create a de-facto oil-encapsulated bubble. This approach provides excellent dispersion, increases selectivity, and most significantly increases the flotation rate of ultrafine coal. Furthermore, atomization of collector/frother combinations yielded improved flotation yields and maintained near uniform froth levels which is a desirable feature in coal flotation. In addition to flotation experiments, microscopic examinations of the attachment of oil-coated bubbles at a coal surface were conducted by attachment-time and contact-angle measurements. The oil coated bubbles attach at significantly faster rates and with a higher contact angle than do oil free bubbles.

Jan 1, 1987

By A. A. Sobek

Controlled release systems delivering the required concentration of an effective bactericide over an extended time period have been developed by The BFGoodrich Company's ProMac® Systems group. The ProMac system is site-specific and includes a four-step approach to controlling acid mine drainage (AMD): (1) Diagnosing the problem, (2) Prescribing the treatment, (3) Supervising the application of controlled release bactericides, and (4) Honitoring the success of applied treatment. The success of the ProMac system is evidenced by improved water quality, healthy vegetation, a reduction in levels of acidophilic thiobacillus, and a corresponding increase in population of beneficial microorganisms.

Jan 1, 1986

By Hemendra N. Kalia

The target to double the coal production by 1995 presents a formidable challenge to the coal mining industry. The mines of future, probably will be located in relatively difficult geological environment because of the exhaustion of the well defined bedded and easily minable deposits. To compound the problems of mining industry will be the reliance of power plants need for coal. The coal must reach the power plants on schedule to avoid expensive blackouts and brown¬outs. It will be imperative that the mines operate without interruptions and at designed capacities. The parameters which have been traditionally responsible for the interrup¬tions of production are: breakdown of production machinery, labor management relations and geological anomalies. Of these three problems, solutions for the first two can be arrived at by developing procedures to correct the situation. A planned maintenance and preventive maintenance program will go a long way in minimizing the equipment breakdowns. Labor relations will eventually improve as the miners begin to enjoy long-term employment. However, with the geological problems, the situation will probably continue to deteriorate and would require careful planning to minimize the impact of geological problems on production and safety. Some of the geological aspects which interfere with production are: faults, washouts, slips and slickensides, water bearing overlying strata, impuri¬ties in the coal seam, and presence of expansive clays in the coal floor. The design of large capacity mines will have to incorporate the geological distur¬bances and mine through them it may become very uneconomical to abandon producing sections because of the presence of the geological anomalies. This paper discus¬ses the geological aspects of coal mining which should receive consideration from the inception of the mining ventures. Pertinent geological aspects are discussed to develop the data base which will aid in evolving safe and efficient mine layouts.

Jan 1, 1976

By John E. Litz

Since the 1974 introduction of catalytic converters to automobiles in the United States, more than 150,000 kg (5,000,000 oz) of platinum, palladium, and rhodium have been used in the converters. An estimated 8 to 10 million converters are being used annually in the United States, each containing from $5 to $15 of PGM metals. In addition, use of converters is beginning in Europe which will significantly increase the quantity of PGM used. Two basic types of catalysts for converters are being used: pellet and monolithic. The pellets are small, discrete spheres or cylinders of gamma-alumina coated with platinum group metals, Figure 1. The monolithic are honeycombs of a cordierite, A13(Mg,Fe)2Si5AlO18, base coated with gamma-alumina and subsequently with platinum group metals, Figure 2. Pellet catalysts are being used by General Motors and American Motors; whereas Ford and Chrysler are using monolithic catalysts. The table below compares the PGM content and value of the catalysts.

Jan 1, 1986

By Alexander Sutulov

It is calculated that since the beginning of last century, which practically coincides with the beginning of the Industrial Revolution, our civilization has consumed around 239.5 million tons of copper (see: Table 1). According to the most pessimistic projections of today, with only a 2.5% annual growth rate in demand, we are bound until the end of this century to consume another 200 million tons of copper in remaining 17 years. A recent study made by US Bureau of Mines (1) indicates that the proven ore reserves of 150 major operating mines and about 120 deposits sufficiently explored for development and feasibility studies accumulate a total mass of 49.3 billion tons of ore, assaying an average of 0.82% Cu and containing around 324 million tons of recoverable copper. Consequently, there is a high grade of probability that the bulk of our future ore supplies, for our demand of, say, next 25 years will cane precisely from these mines. The interesting point in USBM study is that it indicates the recoverable byproduct content of these ores and which is: 118.2 million troy ounces of gold 2277.4 million troy ounces of silver 7.1 million tons of lead 24.7 million tons of zinc 1.3 million tons of nickel 3.1 million tons of molybdenum 765 thousand tons of cobalt, and 720 thousand troy ounces of platinum. This information gives us a relatively reliable profile of our future ores for next 25 years, and thus makes possible evaluation of byproduct credits in our future copper mining and producing activities.

Jan 1, 1983

By K. T. Mau

Hawaii is located approximately 2,500 miles from the mainland, but has basic needs for its thriving developing community. Cement is one of these needs Cement production in Hawaii is not without handicaps. The necessary raw materials are practically non-existent except for limestone. Even at that, the available limestone is marine in origin, coralline in nature and amorphous in characteristics - unlike calcite which is normally the calcium carbonate source for cement manufacture. There is no clay or shale for the argillaceous portion of cement raw mix. Hawaii being volcanic in origin is too young geologically for clays and shales to evolve and whatever there is, most likely is washed into the ocean.

Jan 1, 1982

By Irwin H. Reiss

Gentlemen, the title of my paper is Surface Mining An Interim Land Use. Surface mining has become one of the major controversies of our time. This has happened in spite of the fact that all surface mining to date has involved only 6 million acres out of a total of 2300 million or approximately one-fourth of one percent of the total land area in the United States. I'm not going to dwell on whether peoples' perspectives are out of focus in light of the area involved, the energy crisis, national security, or the international balance of payments problem. While these things are all critically important, it is not the function of this paper to relate to them. Maybe the amount of attention attracted to surface mining is out of proportion to a lot of other things, but I don't feel that we should use that as a basis for procrastination. However, let me categorically state that anything that affects the surface of the earth is a form of land use --- be it an interstate highway, a power plant site, a golf course, a corn field, a strip mine, or the plot of ground on which your house is located.

Jan 1, 1974