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By P. A. Plunkert, D. E. Morse, L. McCartan, S. F. Sibley

The average annual growth rate of real gross domes-tic product (GDP) from the third quarter of 2001through the second quarter of 2003 in the United States was about 2.6 percent. GDP growth rates in the third and fourth quarters of 2003 were about 8 percent and 4 percent, respectively. Many other indicators reflected a rebounding U.S. economy — rising consumer confidence, higher retail sales, greater industrial production and more housing starts. Inflation also reached a 38-year low in 2003. The upward trends in many sectors of the U.S. economy in 2003, however, were shared by few of the mineral materials industries. Annual output declined inmost non fuel mining and mineral processing industries, although there was an upward turn toward yearend as prices began to increase (Table 1).

Jan 1, 2004

By Shiqiang (Rob) Hui, Jiaren (Jimmy) Jiang, Rees Llewellyn, Yongsong Xie

Wear has been estimated to cost the Canadian mining/mineral processing industry over $15 billion per year mainly for repair/replacement of worn parts in 2013. The associated production loss is difficult to quantify but add considerably to the problem. The Canadian oil sands sector which has to deal with extremely abrasive and erosive solids, has traditionally incurred extremely severe and often unique attack. Demonstrable progress in mitigating the wear problems has been achieved through materials development, more informed materials selections, and better component and operation condition designs. An integral contributor to these advances is a long-term collaborative research partnership between NRC and the mining/supply industry. In this paper, this continuing collaboration will be described. A main focus is to identify degradation mechanisms occurring in the most severe and important service applications and to correlate these findings with laboratory test data. Relevant abrasion and erosion (often combined with corrosion) properties have been established and correlated with composition and microstructures for all classes of resistant materials ranging from relatively soft elastomers to ultra-hard ceramics. A comprehensive wear properties database has been compiled. This capability has been instrumental in facilitating the development of improved materials, optimizing materials fitness/selection for service, wear failure analysis, and quality assurance.

Jan 1, 2015

By John W. Amos, John A. Christophersen

The Deister No. 7, "77" and "88" Coal Washing Tables have been used by the coal industry in the cleaning of finer sizes of coal (-1/2") since washing of coals became necessary. This paper will deal with the in-plant use of the CONCENCO "88" Deister Coal Washing Table, along with a brief description of the Deister Refuse Superscalper. Efficient in-plant operation of the Deister Coal Washing Table can be accomplished by the adjustment of six basic variables. These variables are: 1. Headmotion 2. Feed 3. Riffle Pattern 4. Dressing Water 5. End Elevation Adjustment 6. Side Tilt Adjustment VARIABLE NO. 1 HEADMOTION The reciprocating movement of the "88" Table is developed within the headmotion entirely by rotating eccentric weights. Four parallel shafts each carry pairs of eccentric weights (Figure 1-A). The shafts are geared together with gears of 2 to 1 and 1 to 1 ratios, so that the two shafts in vertical alignment which carry the small eccentric weights operate at twice the speed of the other two shafts. The other two shafts are also in vertical alignment with each other and carry large eccentric weights. As power is supplied to one high-speed shaft, once each revolution the forces produced by the large eccentric weights are reinforced and then opposed by the small eccentric weights in a horizontal plane. The direction of movement of the table decks is reversed much more sharply at the forward end than at the backboard end of the stroke, causing material to move toward the refuse end of the table. Because in the vertical plane all centrifugal forces oppose each other and cancel out, there is no vertical movement and virtually no impact to the support steel. The "88" Coal Washing Table is suspended by wire-rope cables from three overhead steel beams, and operates with a perfectly uniform and exact differential motion curve in every stroke (Figure 1-B). The decks, being attached to the headmotion, are reciprocated in a parallel line from the head- motion to the refuse corner at speeds varying from 260-300 strokes per minute. Both length of stroke and speed are set at the factory for the coal characteristic desired and should not be changed. A 3 HP motor is mounted on the top of the headmotion and uses 3 V-belts to transmit driving power to the headmotion. The headmotion must be kept running on a horizontal plane. Punch marks are provided on the side and end of the main frame for use in leveling the motion (Figure 1-C). In leveling the motion, the work must always be done with two cables. To level the long side of the headmotion both front or both rear cables are raised or lowered to bring motion back to level. To level side to side, both right side cables or left side cables are raised or lowered to bring motion back to level VARlABLE NO. 2 FEED When tabling different size coals, each deck of a "88" DIAGONAL-DECK Coal Washing Table will handle feeds as described in figure 2-A.

Jan 1, 1988

By Robin J. Batterham, Stephen H. Algie

It is often stated that innovation is central to the economic survival of mining and mineral processing in the face of global competition, and yet technology is often far from a core strategy in our industry - hence the concerns that are often voiced about the apparent slow rate at which new technology is applied. Much of the discussion stems from a lack of understanding of the role of technology in innovation, and of the role of R&D within the innovation process. To a large extent this has all been said, however, the messages are clear and deserve repetition. This paper expresses the personal views of the authors, based on experience in government-funded (CSIRO and universities) research, and in CRA Ltd, a large mining and mineral processing company. Further than this, it explains how our own development unit within the CRA Group has come to see its key roles as including the transfer of technology, and the training of technologists to move into the operating business units. We conclude that these critical tasks are the keys to creating the environment that will allow us to maximise the contribution of technology.

Jan 1, 1995

By Kyle Apple

The following is a case study of how LuckStone Corporation improved their blast monitoring and documentation program. A number of resources already at their disposal have been utilized to improve the body of data collected from each blast. The tools being used include GPS, aerial photos, and a user-friendly push button format excel spreadsheet. The data collected include product by product records of materials used, distances to all concerned neighbors, seismograph data, etc: The spreadsheet has been designed to perform an ongoing analysis of blasting trends. The program has been carried out at a corporate level and is in use by blasters at each location. This paper addresses the advantages and drawbacks of this program. It also addresses the ways in which the various tools were integrated, Discussed as well is the need for simplicity when bringing “new” technology to the field and the steps taken in familiarizing the end user to changes.

Jan 1, 2001

By B. H. Dunshee

THIS paper is not intended to be a technical discussion of square-set framing as used in mines, but merely a short description of the different kinds of framing that have been used in the Butte mines, and what has been decided upon, after years of practical experience, as being the best, taking into consideration the physical condition of the veins and country rock, and. also the supply of timber available for mining purposes. Butte is, essentially, a square-set district. Virginia City, Nev., was the first mining camp to use this method of timbering, and to Philip Deidesheimer, who went to the Ophir mine in 1860, is given the credit of solving the problem of square-set framing, where large bodies of ore were stoped and the timbers were supposed to hold the ground from caving without any filling. That he did his work well is shown by the fact that the main features of his framing are in use to-day. In the Butte mines the conditions are such that this method of timbering is generally used. We do not, of course, depend upon the timbers any more than is necessary. The worked-out stopes are filled with waste rock as close behind the miners as possible and not interfere with mining operations. The waste rock is obtained from development work on the different levels or from the surface. In the earlier days of mining in Butte there were numerous independent companies and naturally there were different ideas as to the best way to frame the square sets, although the general features were the same.

Jan 8, 1913

By Sims D. A

This paper primarily describes the application of geology to the different mining methods employed in a large underground mine. The steeply dipping stratiform Silver/Lead/Zinc mineralisation at Mount Isa include up to 28 mineable orebodies. The orebodiea are mined by cut and fill, sublevel benching and sublevel open stoping; the method chosen depending mainly on orebody geomechanics.The sources and methods of data collection, and the interpretation process undertaken, are described. The paper emphasises the different geological input required, by each individual mining method, to provide the necessary production and strata control. This input contributes significantly to the success and efficiency of the operations.

Jan 1, 1990

By L. S. Austin

I. Introduction............ 431 II. Organization............ 432 III. Production............ 434 IV. Transportation............ 435 V. Sampling..........436 VI. Concentration............ 440 VII. Blast-Furnace Plant........... 442 1. Construction........... 442 2. Operation............ 450 VIII. Advantages of Large Furnaces........ 455 1. Saving in Fuel........... 455 2. Saving in Jacket.Water..... 455 3. Quick and Large Discharge of Matte and Slag... 455 4. Decrease of Incrustation... 456 5. Elasticity of Operation..457 6. Large Flow Through Fore.Hearths...4. 57 7. Alterations Without Interruption..458 8. Variations in the Composition of Slag....458 9. Less Labor-Cost.......... 458 10. Less Initial Cost.......... 460 IX. Briquetting.Plant........... 460 X. Roasting-Plant............ 462 1. Kilns............ 462 2. Reverberatory Furnaces...468 XI. Converter-Plant........... 474 1. Construction ..........474 2. Operation.......... 476 XII. Flues and Stacks........... 478 XIII. Arsenic-Plant............ 480 XIV. Coke-Washing Plant.... 452 XV. Slime.Ponds ........... 483 XVI. Brick-Plant............ 484 I. Introduction. The Washoe plant; in Anaconda. Mont., together with the local street-railroad, ranches. a foundry and machine-shop. A

Jan 1, 1907

By B. J. Guarnera

There have been major changes in the makeup and nature of the uranium exploration industry in recent years. Significant price increases precipitated an increase in exploration activity-according to the Department of Energy, exploratory drilling in 1977, by 140 companies, was almost 8 million m (26 million ft). This represents a 37% increase over the prior year's drilling. Projections for 1978 indicate at least 9 million m (30 million ft) of exploratory holes will be drilled in the US. Exploration expenditures in 1979, including land acquisition, drilling, and other costs, were estimated by DOE at over $236 million. Domestic expenditures for 1978 are estimated at over $250 million.

Jan 10, 1978

By T. Iwasaki

This paper points out two key elements in resource trade in general and the Canada-Japan relationship in particular. The first is that the advanced countries have a more important role than one would expect in the supply of resources in world trade. Canada 's dual role as a major resource supplier in conjunction with an advanced economy will continue to increase. The second point is the heavy reliance on foreign resource supplies in some advanced economies, particularly in Japan. Finally, as regard the future of the Canada-Japan economic relationship, particularly .in resource development, it is suggested that trade could be enhanced by an accelerated exchange of various types of resources between the two countries. These include natural resource commodities as well as the more abstract capital, technological and human resources.

Jan 1, 1978

By J. Donald Rimstidt, Jeanette K. Jerz

Acid mine drainage is a major environmental problem worldwide. A key to remediating this problem is understanding the rate and mechanisms of the complex, multistep pyrite oxidation reaction under geologically relevant conditions. Because many waste piles are not submerged, a large amount of pyrite oxidation actually occurs in air. We have designed a Barcroft-manometer reactor to measure the rate of pyrite oxidation in air as a function of relative humidity and oxygen partial pressure. The reactor consists of two chambers joined by a manometer. Each experiment occurs at constant temperature, initial oxygen partial pressure, and relative humidity, although these variable can be changed between runs. Oxygen consumption was measured and pyrite oxidation rates were calculated from those data. Initial data indicate that rate of pyrite oxidation by oxygen in humid air is much faster than the rate of oxidation by oxygen in solution. The rates determined by this study can be used to develop better remediation techniques for acidic mine waters.

Jan 1, 2000

By J. Wayne Erickson

Hundreds of millions of dollars have been spent to discover or purchase uranium resources that cannot, or should not, be mined with conventional methods if human, natural and financial resources are to be conserved. Three years ago, an industry-supported research stud was initiated to determine whether a safer and more efficient (in terms of cost and environment) uranium mining method could be designed to replace existing techniques. As a result of this study, the "underground in situ" method was conceived and developed to the stage where it is now feasible. This approach involves: (1) sinking a shaft; (2) driving a drift on the ore horizon the length of the ore body; (3) drilling almost-horizontal long holes the width of the ore body; and (4) oxidizing and leaching the uranium drawn from these holes. The method is unique in that the uranium is removed with a minimum of disturbance to the natural hydrology of host or surrounding sands.

Jan 11, 1978

By Niels Verbaan, Ernesto Bourricaudy, Ronald Molnar, James Brown, Sunil Jayasekera

"SGS Minerals commissioned an internal R&D program to develop in-house expertise to design, set up and operate REE separation pilot campaigns at its Lakefield, Canada site. A team approach was used that included expert consultants in the field of REE separation as well as in-house expertise supported by the on-site Analytical Laboratories.A mini pilot scale SX circuit was designed and constructed consisting of several modular banks of 30 stages each. About 80 stages of mixer-settlers were used to separate Pr and Nd from La and Ce contained in a synthetic REE chloride stream simulating the raffinate from an initial La-Nd|Sm-Lu+Y separation.Two pilot campaigns were operated totalling 25 days of 24/7 operation with 99.4% plant availability in the final 20 day campaign. Purities of > 99.9% in the Pr-Nd strip liquor and > 99% in the La- Ce raffinate were achieved and simultaneously sustained in the second campaign for prolonged operating periods. Key to controlling and adjusting the circuit was the rapid assay turnaround (as low as 2 hours) provided by the on-site SGS analytical lab. This permitted the operating team to modify conditions and observe the effect of changes relatively quickly considering the large number of stages. A portable XRF analyser was also used to track evolving assay trends in the circuit. The small physical size of the circuit enabled longer operation with a limited amount of sample.This paper discusses the design of the circuit, operating conditions, some of the key operating factors and controls and results obtained.INTRODUCTIONSGS Minerals commissioned the design of and built a solvent extraction (SX) pilot plant for the separation of rare earth elements (REE). The plant consists of a battery of 120 mixer-settlers set up in a dedicated piloting facility.The purpose of the programme was to develop capabilities and in-house expertise in REE SX separation technology. The program aimed to establish operating procedures, sampling regimes, and analytical methodologies and protocols for this type of process/plant. A team comprised of SGS personnel and several external consultants with prior industrial and REE separation piloting experience was assembled to achieve these objectives."

Jan 1, 2016

By C. D. Wittreich

The University of Idaho, Department of Metallurgical and Mining Engineering, through the Generic Mineral Technology Center, has been engaged in mine design research at the Lucky Friday Mine, Mullan, Idaho. The purpose of the research is to develop and implement the longwall underhand cut-and-fill mining method for conditions at the Mine. The longwall underhand cut-and-fill mining method involves backfilling mined stopes with a compacted tailings-cement mix. After the backfill has been allowed to cure, mining is resumed from underneath. Horizontal stresses in the Lucky Friday Mine are exceptionally high and rock bursts are a common problem. Beus and Chan (1980) have reported a 2:1 horizontal to vertical stress ratio at the mine with a 65-MPa (9,500-psi) maximum horizontal stress at the 1,295-m (4,250-ft) level. Using this mining method under these stress conditions, it is desirable to have a backfill material that has sufficient strength to safely carry the high horizontal wall loads while minimizing external steel supports.

Jan 1, 1987

By T. Bertke

This document assesses the environmental aspects of a preliminary design for processing kaolin clay as the domestic resource for recovery of alumina by a hydrochloric acid leach-HCl gas induced crystallization process. The report covers waste sources, control measures, and potential environmental and health effects applicable to the process technology.

Jan 1, 1980

By R. L. Grayson, S. S. Eslambolchi

"In making strategic economic decisions, it is important for a mining company to gain insights on the impact of significant political, social and economic issues when planning for present and future mines. The size of any mine, measured by the average number of employees working in the mine, will likely vary according to the pressures generated by the significant issues from one year to another. The objective of this study is to develop a model that represents U.S. underground coal mine size transitions during the period 2002-2012 using data derived from the MSHA databases. Coupled with information on significant issues over the past ten years, this model is used to gain insight on the impact of the issues on mine sizes. Results indicate that the structural impact of the combined driving pressures can be discerned by examining the year-to-year stability of mine-size categories. The effects of The MINER Act, the Obama Administration environmental policies on coal, and the coal market are evident. The lessons learned from these analyses give good insights on what the industry and market responses have been on the structure of the underground coal industry over the period of study. INTRODUCTION It is apparent that key driving issues affect the structure and viability of the coal industry. The driving issues may be political, social, and/or economic in the final analysis, but are generally rooted in reaction to dramatic and publicized events or movements. Mine disasters, an increase in miners’ disease prevalence, strife in the coal fields, and negative environmental impacts on air, land or water can capture the attention of the media and the public. Some of the issues occur over a long period of time, like the current global climate change movement. The coal industry veteran can sense the changes in political and social sentiment, and attempt to react to the economic repercussions; however, the insights from the media and from unique combinations of driving pressures are difficult to fathom. Thus decisions made on inadequate information related to the driving pressures and their likely impacts could lead to missteps in corporate and market restructuring. One way to gain some more insight on the potential impacts is to examine the complicated restructuring of mine operations in reaction to the driving pressures of the recent past. This paper examines an 11-year history of the changes in the underground coal industry structure, as reflected by changes in the numbers of mines in various statuses by mine-size categories. Superimposed on the results of mine-size changes is a mapping of the key driving pressures that occurred over the same period, 2002-2012. It is assumed that using this methodology, some important insights can be gained on the immediate and delayed responses to the driving pressures during that period."

Jan 1, 2015

By Peijian Zhang, Yansheng Liu, Yuusaku Tominaga

The directions for ventilation control are often given in linguistic styles such as "if the airflow rate measured is small, a high value of rotation on a local fan should be chosen." In order to control the underground climate using a computer instead of a human being, both the reliability of data values measured underground and the application of human recognition of data values are required. The efficiency of data transmission is dependent on a method of checking a signal which is changed by mixing noises resulting from cases of electrical and mechanical damage to cables. In the study, fuzzy reasoning is adopted to choose a checking method for underground conditions from a normally operating state to an emergency. Fuzzy reasoning is applied to control airflow rate under the linguistic control rules given. It is shown that an effective series of linguistic control rules derived by fuzzy-sets theory is available in ventilation control when used in conjunction with an air velocity sensor, a computer and a local fan with thyristor control. Moreover, a system to make an optimum series of linguistic control rules for ventilation control is introduced.

Jan 1, 1987

By Charles Behre

THIS paper deals with recent geologic studies in the slate belt of Northampton, Lehigh and Berks counties, Pennsylvania. The work was conducted under the auspices of the Pennsylvania Topographic and Geologic Survey. Three years have now been spent in detailed consideration of the economic geology of this region. In the field, particular attention was paid to the bearing of geology on quarry development and property valuation and the object of this paper is to summarize the results from that viewpoint. Excellent studies of a somewhat similar nature have already been carried out by Bowles,1 but with the emphasis upon the details of quarrying and fabricating methods, rather than upon the geologic relations. THE NORTHAMPTON-LEHIGH-BERKS DISTRICT Location The region here discussed lies in east-central Pennsylvania and extends southwestward from Delaware River, on the New Jersey line, to the Schuylkill in north-central Berks County. It is an elongated belt occupying the northern sections of the three counties mentioned and lying along the southern edge of Blue Mountain. Its length is about 50 miles and its average width five or six, though in places it attains a maximum of 10 miles.

Jan 1, 1928

By B. M. Bench

This Bureau of Mines report describes photo lineaments obtained from stereoscopic examination of vertical aerial photographs and by the Ronchi grating study of aerial photoindex sheets. The photolineaments are compared with the trends of oriented fracture systems procured by measuring the compass direction of joints in bedrock. The relative reliability of the methods is shown, and the results are presented in graphical, tabular, and written form. Analyses of field measurements of strikes of bedrock joints in the project area indicate for the most part two intersecting sets of major joints oriented N 76° W -N 15° E, and N 57° W -N 27° E. The analyses of lineaments determined by stereoscopic examination of aerial photographs show dominant trends of lineament zones of weakness to be an average of N 65° W -N 20° E. Analysis of lineaments found by Ronchi grid viewing of aerial photoindex sheets indicate dominant trends of N 70° W -N 27° E. The three methods give similar findings and verify the work of previous authors. The Ronchi grid method is a useful guide, but it cannot be substituted for the two more painstaking methods.

Jan 1, 1977

By Henry C. Meeves

The Bureau of Mines, between 1956 and 1963, examined 18 major pegmatite districts in Arizona, Colorado, New Mexico, South Dakota, Utah, and Wyoming to evaluate their content of beryllium, a material in short domestic supply that has become increasingly important to modern industry. This examination report includes the salient statistics on the production of pegmatite minerals other than quartz and feldspar; and brief descriptions of 170 specific pegmatite deposits.

Jan 1, 1966