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By Marlion T. McQuinn

This paper will discuss the design, construction, and performance of the support of excavation on the Dulles East and West Automated People Mover Tunnels and Station projects. The elements of the system included drilled soil nails and rock anchors with reinforced shotcrete to the excavated face. We will discuss the geotechnical characteristics, design and construction considerations, loading criteria, construction techniques, schedule constraints, and performance of the support of excavation system. In consideration of the conference theme, there will be a discussion of the application of the real-time instrumentation monitoring program. The project team worked to design and install approximately 710,000 square feet of shotcrete and 19,000 soil nails/rock anchors as well as excavate over 720,000 cubic yards of rock materials within 15 months and in such a manner as to minimize the disruption to airport passengers and operations.

Jan 1, 2006

By Mehmet Guney

At the Armatcuk mine in Turkey, various modifications of sublevel methods have been tried during the last decade in an effort to eliminate gob fires, dangers from roof falls, and surface subsidence, and also to increase extraction efficiency. From the experience thus gained, it was decided that the most likely system to give maximum benefits, considering the existing geological conditions and coa1-seam characteristics, was hydraulic stowing. This paper examines trends in the working techniques of hydraulic stowing and discusses the favorable results and technical problems that the method produced at Armutcuk. The Armutcuk mine, a subsidiary of Eregli Coal Mines (EKI), produces 1300 tons of run-of-mine coal daily from thick (about 10-90 ft) and highly dipping (about 50-90°) coal seams. The coal is highly volatile with good coking properties that make it highly suitable for industrial use. Most of this coal is used in the iron and steel industry at Eregli on the Black Sea coast. Complete recovery of the coal is of vital importance to industrial development and progress. Initial coal extraction was carried out by means of a sublevel mining system modified to accommodate local geological conditions and coal seam characteristics. This method is similar to that employed in metalliferous mines. Several problems arose from the application of the method, one of them being the prevalence of gob fires which caused periodic shutdowns in some sections. To achieve maximum coal extraction with minimum dilution, to eliminate gob fires and surface subsidence, and to reduce fatal accident rates, a decision was taken to change from this method to a hydraulic stowing system. The pres- ence of large deposits of conglomerate and sandstone on the surface contributed to the decision to employ this new method. Although hydraulic stowing practices have been carried out in America and Germany, Upper Silesia may, so far as coal is concerned, be considered the birthplace of the method. Here the process was adapted to thick coal seams on a large scale to reduce dangers from gob fires and damage from surface subsidence. Today, the mining system is not only widely used in the coal mines of France, the Saar, India and Poland, but has also been successfully applied to the iron ore and potassium salt mines in Russia and Germany. LOCATION AND HISTORY The Kandilli-Armutcuk coal field, the most western outcrop of the North Anatolian coal basin, extends for five miles along the Black Sea coast (Fig. 1). The Armutcuk Mine is situated on the southern boundary of the coal field about 40 miles from Zonguldak and about 12 miles from Eregli. The history of coal mining in the North Anatolian coal basin goes back more than a century. Mining commenced on a small scale in the Kandilli-Armutcuk coal field in the late 1880's, and from this time until nationalization in 1940 the mines were operated by private Turkish and foreign interests. In 1940, Eregli Coal Mines was established to takeover the management of these enterprises. The Armutcuk Mine was developed for the first time in the mid-1940's. Since then it has been in continuous production and it now produces an annual 440,000-ton run-of-mine output from which 320.000 tons of salable coal is obtained. MINE GEOLOGY The carboniferous inlier of the Kandilli-Armutcuk coal field crops out over an area about three miles long and one mile wide. The major part of the inlier consists of the Namurian formation with only a relatively small area of Westfalian-A visible on the surface (Fig. 2). The Namurian formation, which has no exploitable coal seams in the Armutcuk Mine, consists mostly of arkose sandstones and black shales often having

Jan 1, 1969

R. C. BUCKETT (Lake View and Star Limited) : At the outset I should like to add my congratulations to those already extended to Mr..Norwood on his excellent paper, which has given us all an inspiration to strive further to improve our plant recoveries. In some respects this paper has left us so little to discuss without considerable time spent on. further research work. At all points one is met by a baffling array of facts which leave one feeling hesitant to speak.The careful and methodical way in which Mr. Norwood went along step by step until all channels of research presenting themselves were tested to his own satisfaction leaves me with but a few comments to make. Particularly striking to me is the explanation of the residual gold values in calcines by recrystallization of haematite and here is a line to be attacked by future studies. This will be mentioned again later.Particularizing on the paper, the first point that struck me was the method of change of pyrite through to the final haematite. I have never been able to satisfy myself that a sample taken from various positions along a roaster when cooled, as described on p. 397, represented a fair sample of the conditions at that point, but I must confess that I have not found a substitute that did satisfy me.However, the following figures are illuminating... But to fill dry a receptacle of known volume with calcines, as described by Mr. Norwood, gives the following apparentspecific gravities:

Jan 1, 1940

By AIME AIME

NEW place was assigned to the women for their headquarters at the annual meeting of the Auxiliary but they, as usual, occupied a large place in the activities of the annual meeting. The alcove on the Thirty-ninth Street side of the building was a busy place on Monday morning, as the members of the various sections from New York to California greeted each other. The registration was conducted under the supervision of Mrs. Wolfes, Miss Georgene Davis and Mrs. Jennings, while Mrs. Hursh, Mrs. Hyde, Mrs. Charlton Reynders, and others dispensed tickets to the various functions that had been provided for entertainment. There seemed to be the usual number registered, but when only one member of the District of Columbia Section made herself known everyone wondered why the large delegation of last year had so dwindled. The explanation appeared next day, when a number of others from that Section arrived, telling of a delightful reception on the night before, at the White House. Mrs. Hoover had honored the "Canaries"¬(the organization of Lone Girl Scout' workers) the officers of the Section, and their husbands, who for once became only "so and so's husband." Luncheon was served on the fifth floor on Monday, the hostesses for that day being Mesdames C. F. Ayer, Willis Burns, G. W. Farny, H. G. Moulton, and T. T. Read. A number of sight-seeing trips had been arranged for the afternoon. The most popular proved to be an expedition to the new Riverside Church; where Dr. Fosdick is pastor. Guides were there to conduct

Jan 1, 1931

By PAUL M. Tyier

NOW that analytical chemistry has gone so far to debunk early misconceptions about minerals, the fact that the light of exact knowledge still fails to illuminate many dark corners is often overlooked. By combining the skills of the physicist with those of a chemist, the identification of minerals has become an exact science and the presence of even minute traces of impurities and extraneous elements is readily revealed by spectrographic means, Granted that we can learn all there is to know about the composition of a substance and even about its physical propertied (which latter assumption is somewhat far-reaching) it still does not follow that we clearly understood its commercial designation or utility.

Jan 1, 1941

By Jukka Tuominen

The history of making blister copper in an Outokumpu Flash Smelting Furnace dates back to the late 1960?s, when Outokumpu first piloted the Outokumpu Direct Blister (ODB) process. The first commercial scale applications have been in use at Glogow, Poland, since 1978 and at Olympic Dam, Australia, since 1988. These applications utilize special concentrates, which are low in iron, and thus the formation of slag is also low. In 1995 the same principle was applied to smelting copper matte into blister copper in industrial scale at Kennecott Utah Copper. This application, the Kennecott-Outokumpu Flash Converting process, will celebrate its 10th anniversary of commercial scale operation this year. This paper outlines the development in efficiency and flexibility of Blister Flash Smelting processes compared to other smelting and converting options. The focus is on the economical aspects i.e. on the total feasibility of both greenfield investment projects and revamping of existing smelters.

Jan 1, 2005

By R. A. Reiley

Introduction Democratic countries are founded on the principle that all citizens have the right to participate in policy setting and decision-making processes. Citizen participation is especially evident in environmental issues and policies. In the United States, there are currently over 10,000 environmental organizations and new ones are being formed each year. Many of these organizations are formed on a watershed basis and are particularly concerned about the impact mining has on the environment. While the environmental issues vary from area to area, most concerns center around mining impacts related to subsidence, water pollution, and water diversion. Citizens have a number of avenues for participating in lawmaking that affects the mining industry. Some of these avenues include participation in litigation and citizen ballot initiatives. In addition, there are less formal methods of participation that include attending public meetings, commenting on agency rules or lobbying on specific legislation. The intent of this article is outline the various public participations mechanisms, highlight the latest legal developments that have affected mining industry through citizen participation, and briefly discuss emerging issues.

Jan 1, 2001

By Hardwick F. W., O'Shea L. T.

The survey covers: coal-mine lighting prior to the invention of the safety-lamp, including candles, the flint-and-steel Spedding mill, and mirrors; the growth in knowledge of firedamp; the Society in Sunderland for Preventing Accidents in Coal Mines; Dr. Clanny's blast lamps and steam lamps; George Stephenson's tube-and-slider lamp, triple-tube lamp, punched-plate lamp and gauze Stephenson lamp; Sir Humphrey Davy's lamps; the controversy over invention priority, and other early forms of safety-lamp; 1816-1835 developments including the lamps of Upton and Roberts, M.Mueseler, John Martin, Dr. Clanny (new 4th lamp), M. Agre, John Newman, Gossart and Roberts, Francis Ellis, John Dillon and Mr. Wood (refrigerating lamp); 1836-1843 developments, notably of Mueseler lamps; 1844-1866, including lamps of the Davy, Clanny, Boty, Eloin and other types; 1867-1879, including the Gray lamp; 1880-1887, including the Marsaut lamp; and 1888-1913. Detailed reference is made to the findings of various relevant Royal Commissions and appendices include a list of the safety-lamps described in an appendix to the 1886 report and a publications list. The paper was prepared for the International congress of mining, metallurgy, applied mechanics and economic geology to have been held in London in July 1915. Discussion (p.718-724) includes a brief comment by Blackett W.C. and a longer contribution by Ashworth J., with the authors' response

Dec 1, 1916

By A. L. Podia

The purpose of this research was to develop a system capable of detecting changes in the structure of rocks, leading to failure of mine roofs, and/or excavations. A prototype system was developed, field tested and delivered to the United States Bureau of Mines for further evaluation and research. This system is based on the analysis of acoustic signals generated on the surface of the roof by an impact device and which are reflected or backscattered by flaws and discontinuities in the rock. The specially designed impact source is capable of generating high frequency acoustic signals with excellent repeatability. The system can also be used in conjunction with conventional acoustic pulse transducers. The received signal is digitized and the data transferred to a minicomputer for processing and display. This capability allows the immediate determination of wave velocity and/or distance to a reflecting interface. Various data processing techniques such as averaging, differentiating, and comparing of different signals can be selected by entering the appropriate commands on the keyboard. Being a programmable system it is possible to implement more advanced signal processing techniques. All results as well as the signal are displayed on a CRT. Furthermore, a permanent record of the data can be generated on paper tape, which can be reentered and processed at a later date. A communications interface allows transmission of the sampled signal to a large scale re-mote computer. The system was tested extensively in the laboratory, and field tested at the York Canyon Coal Mine. These tests proved the feasibility of operation in the mining environment. Results indicate that further investigation and development will have to be undertaken to fully develop the potential of this system in satisfying the goals of this research.

Jan 1, 1973

By Donald M. Liddell

ALTHOUGH the midday lunches of business associations have been re-echoing the phrases that re- search would lead us out of the depression and that the last place to economize is on research, nevertheless most executives apparently concluded that it was their neighbor who ought not to economize in research, and that in their own plants what had been discovered in 1929-30 was sufficient to lead them out of the wilderness. At any rate, I have discovered much less that seems worth noting, and compared with 1931, the report volume of the committee members is off about 40 per cent, and compared with 1929, about 80 per cent. Evidently there is some hookup with the +tee1 industry as to output, and the Report Reading Committee should investigate this and the relative use of commas and periods.

Jan 1, 1933

By Catharine T. Fogg

The Bureau of Mines investigated the availability of flake and high-crystalline natural graphite from 4 domestic and 25 foreign mines and deposits in 11 market economy countries (MEC's). Demonstrated resources were estimated to be 95 million metric tons (Mmt) containing 5.61 Mmt of recoverable flake and high-crystalline graphite products. Fifty-five percent (3.17 Mmt) of the total recovered product is estimated to comprise plus 100-mesh (150-µm) flake pro-ducts and "lump" and "chip" high-crystalline products, designated as "graphite A" in this study; 45 pct (2.44 Mmt) of the total is minus 100-mesh (150-µm) flake products and "dust" high-crystalline products, designated as "graphite B." Total production costs, including all costs needed over the life of each operation, were determined at a 0-and 15-pct discounted-cash-flow rate of return (DCFROR) for both graphite A and graphite B products. For a 15-pct DCFROR, 1.74 Mmt (54.9 pct) of the graphite A products is available at $600/mt or less and 2.13 Mmt (67.2 pct) is available for $800/mt or less. For the same DCFROR, 1.08 Mmt (44.3 pct) of the graphite B is available at $200/mt or less, and 1.71 Mmt (70 pct) is available at $325/mt or less. No domestic resources were determined to be economic at present prices. A sensitivity analysis of the relative economics of the Alabama graphite deposits under various operational parameters is presented in an appendix. All evaluations are in January 1984 dollars.

Jan 1, 1987

By Enver Alan, MerkeziYapı

People are migrating because of economic, social, natural and political reasons. These natural and humane factors effects the distribution of populations. The need for tunnels has grown in order to provide a comfortable life and reduce losses such as waste of time, labor, energy, efficiency and so on. It is inevitable to carry out excavations in rock tunnels (shears, platforms, lines, connections, wastewater, distribution, energy, transportation etc.), that will be built by excavating with conventional method, by controlled blasting regarding with constrains. In this study of applied explosives engineering the blasting applications are evaluated, which were carried out for research and development purposes at Yenisahra Station tunnels in Kartal Formation which was built with the aim of solving İstanbul's transportation problem within the framework of the Kadıköy-Kartal Metro Project. Twenty-four shots were made by using explosives in 60 blastholes that were drilled in the tunnel faces, which were located between and outside of two different faults. Six microphones were used to measure the air shock and eight geophones were used to measure the parameter values of the vibrations (particle velocity, frequency, displacement, acceleration, amplitude, wavelength etc.), which were placed at predetermined points of the surface, occurred during the blasting applications. Data from the geophone and microphones were recorded on six seismographs. The coordinates and the distances between the shot points and the measurement stations are determined by an electronic theodolite. The total number of seismic records, recorded in seismographs, is 118. The number of records of vibrations that crossed the faults is 42 and the number of records of vibrations that did not cross the fault is 76. The particle velocity, frequency, amplitude, acceleration, displacement and wavelength were measured in transverse, longitudinal and vertical directions. The total number of measurements is 354. By evaluating all seismic records, the effect of delay intervals, faults and scaled distances on the particle velocity, frequency, amplitude, displacement, acceleration, wavelength and air shock were investigated. When the vibrations formed during the Research & Development (R&D) blasts were examined, it was determined that the parameter values of vibrations that crossed the faults are lower than the ones that did not cross the faults. In addition, when the particle velocity values of all vibrations are examined according to the present circumstances, it is determined that the waves did not cross the fault in all delay intervals are superposed in all directions, and that the least superposing occurred in the 50 ms delay range.

By Kot F. Unrug

In the premining stage of engineering design, the only available data are obtained from core drilling. It is often not sufficient for a realistic design of strata control. During the development, an access to the geological formation is created, enabling in situ testing. Obtained data can be utilized accordingly to improve preliminary design. The available methods for testing are described with emphasis on their application for a longwall system. The optimum design ensuring continuous operation of the high output longwalls is critical because their downtime is very expensive. Optimization of ground control measures also has the potential for substantial savings by elimination of unnecessary support.

Jan 1, 1994

By K. Goshtasbi

In this paper a genetic algorithm is used in a heavily jointed rock mass in order to investigate the critical circular slip surface and modification of slope surface. This method was applied to the southern wall of the 6th Golbini Jajarm bauxite mine. The mine is the largest bauxite deposit in Iran, located to the northeast of the town of Jajarm in the Khorasan province. Estimated reserve of bauxite in this deposit is about 160 million tonnes. Field and laboratory investigations were conducted in order to determine rock mass behaviour. A genetic algorithm code that uses the Simplified Bishop method as an objective function was developed for findingt he safety factor of circular slip surfaces. Sensitivity analysis was applied to determine the optimum values of the genetic algorithm variables, such as population size, selection method, crossover and mutation rates. After finding the critical circular slip surface, slope modification is carried out by removing unstable sections from marked critical slip surfaces, and this process is repeated until the last unsafe section is removed. Based on this code, modification occurred during 7 steps, by reaching a safety factor of 1.3 in the last step. Finally, the modified slope angle of the southern wall of the 6th Golbini Jajarm bauxite mine was determined to be 48.44 degrees. Keywords: Genetic algorithm, slope modification, circular slips surface, 6th Golbini Jajarm bauxite mine .

Jan 1, 2008

By Primak. George J.

"In the development of a new product as well as during its introduction on the market, it is very important to give due consideration to problems involving patents, licenses and trade marks. At the very beginning of the research and development program, it is obviously essential to ascertain, through a suitable patent search, that the product in question will not infringe any patents which are still in force. Then, a possibility of achieving one's own patent or proprietary position on the product or the process of its manufacture should be carefully explored. Licensing arrangements that one may reach with respect to patents and know-how covering such new product may, in the final analysis, determine its over-all success or failure. If one can count on licensing revenues or some favourable cross-licensing arrangements with respect to a newly developed product, this may go a long way to achieving profitability and success. The selection of a good trade mark is probably one of the most important acts that one has to perform once the product is developed, as customers will identify the new product by such a trade mark. In many instances, successful marketing and widespread acceptance of a product are largely due to its appealing name or trade mark, accompanied by proper promotion and advertising. Once the trade mark has been adopted, it should be registered in the Trade Marks Office to provide the protection afforded by federal statute. If the product is to be manufactured, sold or licensed in some other countries, similar considerations should be made with regard to each such country."

Jan 1, 1973

By F. D. Forgeron

"ONE OF THE FIRST DOCUMENTED APPLICATIONS of soil geochemistry in the Canadian Shield was that carried out by Chisholm in the Kenora district in 1949. This survey proved successful in outlining sulphide-associated gold veins utilizing cold-extractable metals. Since then, mining companies, government agencies - both provincial and federal - and universities have conducted soil investigations. Some of the results are documented in publications, others are on open file in provincial and federal mines departments and, unfortunately, many other investigations with both successful and unsuccessful results are buried in company files or have been discarded. This paper deals with soils within the scope of chemical studies of overburden in the Canadian Shield. The subject is a broad one and some definition is required. The soil investigations discussed herein are those aimed at the testing of specific targets more or less in the source area. This definition distinguishes soil investigations from other overburden studies which commonly monitor metal accumulations at some substantial distance from the metal source. Naturally this distinction is relative, because in many instances there is overlap."

Jan 1, 1971

By Sidney Katell

This report covers the period January 1962 through December 1962; it is a continuation of the series that began with the publication of Information Circular 7510 in October 1949. Also, it is the fourth in a series of reports prepared under a cooperative agreement between the Bureau of Mines and the American Association of Cost Engineers. The agreement provides for the publication of an annual cost bibliography with the work load evolved in the preparation shared equally. The abstracted articles, concerned with all facets of cost engineering in the field of chemical and petroleum plants and related subjects, are from tile following sources: 1. American Association of Cost Engineers Bulletin. 2. Bureau of Mines Information Circulars. 3. Bureau of Mines Reports of Investigations. 4. Chemical Engineering. 5. Chemical Engineering Progress. 6. Chemical Week. 7. Coal Age. 8. Coal Utilization. 9. Cost Engineering. 10. Hydrocarbon Processing and Petroleum Refiner. 11. Industrial and Engineering Chemistry. 12. Nucleonics. 13. Oil and Gas Journal. 14. Petroleum Management. 15. World Oil.

Jan 1, 1963

By Sidney Katell

This report covers the period January 1962 through December 1962; it is a continuation of the series that began with the publication of Information Circular 7516 in October 1949. Also, it is the fourth in a series of reports prepared under a cooperative agreement between the Bureau of Mines and the American Association of Cost Engineers. The agreement provides for the publication of an annual cost bibliography with the work load evolved in the preparation shared equally. Tile abstracted articles, concerned with all facets of cost engineering in the field of chemical and petroleum plants and related subjects, are from tile following sources:

Jan 1, 1963

By Sanjeeva Latchireddi

"Deteriorating ore grade and high demand of metals has tremendously influenced the unit capacity of SAG mills. Pebble circuits have been added to the existing SAG circuits to increase their unit capacity. To make the pebble circuits justifiable, the grate openings are increased almost to 4.5 inches to draw large quantity of pebbles. The inherent transportation problems associated with SAG mills in closed circuit with pebble fraction are more complicated than the single stage SAG mill operation, because the coarse pebbles behave significantly different to that of slurry in pulp lifters. In addition, operation of mills at higher speed, to take advantage of precise design of high release angled shell lifters significantly reduces the discharge efficiency of the conventional pulp dischargers. The presence of a sizable quantity of pebbles in the pulp lifter limits the space available and reduces the flow gradient through the grate thus increases the load inside the mill and hence the mill power-draw. This paper analyses all the problems associated in discharge of slurry and pebbles in SAG mills with pebble circuits. The Outokumpu patented Turbo Pulp Lifter (TPLTM) aims at eliminating the inherent material transport problems to ensure good grinding conditions. Recent installation of TPLTM in a 26-ft SAG mill has proven these claims by reducing the specific power consumption while increasing the mill capacity.INTRODUCTIONThe conventional wisdom is to look at the semi-autogenous grinding (SAG) mill as just another grinding mill in which ball charge, mill filling, and mill speed are varied to attain maximum throughput. Liner design for the SAG was also approached more from a wear perspective rather than a metallurgical and hydraulic-flow perspective. The extensive research work carried out by Latchireddi and Morrell (1997,2003a and 2003b) has demonstrated to think of the SAG as more of a pump in which the grates and pulp discharger end (“impeller”) were designed to efficiently discharge the product sized particles smaller than the grate size with minimal recirculation out of the mill.The rock load in the mill is essentially depends on ore characteristics and the discharge rate of broken particles. The discharge rate of the product material depends on how efficiently the discharge pump (grate and pulp lifters) is operating. Similar to the impeller design affecting the pump capacity, the pulp lifter design affects the discharge capacity (or mill throughput) of the SAG/AG grinding mills. The general arrangement of AG/SAG mills discharge system is shown in Figure 1."

Jan 1, 2007

By B. C. Alberts

Planning the use of South Africa's energy resources, especially coal, is of the utmost importance. The State and the mining industry require reliable official estimates of the economically mineable coal reserves for planning purposes. An overview of al the previous reserve estimates is given, with specific attention to the two most recent estimates-those of Petrick and De Jager. The differences between these two estimates are highlighted. The following important aspects are discussed: . the need to update the information regarding South Africa's mineable coal reserves, . the necessity of understanding and agreement between the coal-mining industry and the State department responsible for updating the coal-reserve data, and . the importance of the specific assumptions used in the updating of the data. A downward adjustment of mineable reserve figures is proposed, and the factors that influence the meaningful exploitation of the coal reserves are discussed. A recommendation is made as to how the Waterberg coal reserve should be exploited, and it is concluded that the Soutpansberg Coalfield cannot be exploited economically in the foreseeable future. An evaluation of the status of the coal-export trade is made and compared with the assumptions and targets set at the start of the coal-exportation scheme. The comparison shows the extent to which the exploitation of the coal reserves is being negatively influenced by the current market situation. Recommendations are made regarding planning for the coal-export market, and the aspects that have to be taken into account to keep South Africa in the export market are identified. Reference is made to the fact that the present unrestrained wage and salary adjustments, which show a total disregard of South Africa's poor productivity record, require serious thought and speedy rectification if the country is to survive in the export market. A salary and wage strategy must be developed to suit the specific needs of the Republic of South Africa.

Jan 1, 1987