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My roots span four generations. My great grandfather, Christian Frederick Fisher, along with twenty-one others was drowned in the New Australasian mine disaster at Creswick in Victoria in 1882. My grandfather, also named Christian Frederick Fisher, escaped and then followed a career of shaft sinking for large companies and operating small mines (very unprofitably according to my father) when funds allowed. My father, an excellent practical mining and mechanical engineer, was also a small miner and my early entry into the industry was, like many before me, very basic. My introductions to the business end of a No. 4 shovel, drilling with hand steel and later with jack hammers without the benefit of airlegs, feeding heavy cordwood to hungry boilers and felling trees for mine timber soon dispelled any illusions I had that mining was a bed of roses.Before it became well known I knew "Life was not meant to be easy".In a family-owned small gold mine in a remote part of Cape York Peninsula in far north Queensland I was fortunate in obtaining an excellent grounding in reef and deep alluvial mining. Operating in vertical and underlie shafts the variable ground conditions often required close timbering. Steam pumps were used underground and steam winders for hoisting.The complete absence of municipal or government infrastructure in this remote mining field threw responsibility on each mine operator to be self-sufficient, and responsible for mine development and installation of crushing and milling equipment, accommodation and water supply. Conditions, although harsh, were acceptable in the 1930s, and fostered great self-reliance.The first crushing from our Black Cat Mine in 1935 returned nearly 200 oz from 10 tons of ore. Gold was then worth $13 an ounce compared to about $400 an ounce today; but in those depression years of the 1930s our operation was profitable.This basic education not only returned dividends when confronted with difficult mining problems, but created a deep respect for the miners who develop the small mines and who continue to contribute to the industry today, often under difficult conditions.Australia and mining are synonymous. The industry has been immortalised by the famous historian, Professor Geoffrey Blainey, in his book "The Rush that Never Ended".Initial gold discoveries were concealed and exploration was frowned upon by authority as being disruptive to early rural development. But with the discovery of gold in the Bathurst area of New South Wales by Hargreaves in 1851, the rush to the gold fields began followed by an influx of migrants. The traumatic effect on industry and society that followed, created the pattern of the love-hate relationship that at times became temporarily submerged, but is so evident today.In the harsh economic climate of the 19th century with low wages and no welfare, the opportunity to wrest riches from the earth was literally "rushed" by the adventurous, the poor, the rich, people from all walks of life. Pressures developed on preFederation Governments to provide law, order and infrastructure to the rushes that have never ended.

Jan 1, 1984

By E. G. Valdez

Laboratory research demonstrated that ceramic wall and floor tile can be produced from electric furnace phosphorus slags composed of calcium silicates. Grinding the slag in a pebble mill, followed by magnetic removal of deleterious magnetite, produced a raw material that could be compounded and formed into wall tile by dry pressing, sintering, and glazing. The effects of process variables such as forming pressure and sintering temperature were investigated. Wall tile bodies produced by this method were comparable to commercial tile. The tiles were readily glazed to a smooth shiny finish and met ASTM Specifications C34-62 for structural clay load-bearing tile. The estimated cost of producing wall tile by this method compared favorably with the retail market value for similar wall tile. Addition of borax or other additives to the ground slag followed by dry pressing and firing likewise produced a commercial grade of floor tile.

Jan 1, 1974

By T. H. Patching

This paper provides a review of the available information on the origin and mechanisms of the release of gas from coal seams. With the opening up of new mines in Western Canada and the increased mechanization of underground coal mines, the study of gas emissions is of increasing importance in providing safe working places underground.

Jan 1, 1970

By Isa Nozari, Asghar Azizi

The extraction of copper from sulfate leaching liquor was investigated using Acorga M5640 commercial extractant in kerosene diluent. The effects of important factors such as the extractant concentration, contact time, liquor pH, and temperature were examined on the separation factor Cu/Fe and the extraction efficiency of copper. The results indicated that nearly 92.32% copper was extracted from the leach liquor at 10% (v/v) Acorga M5640 concentration, 1:1 aqueous/organic phase ratio, 20 min contact time, pH 2.5, and 25 °C temperature. Also, the further increase in the values determined had no positive impact on the extraction of copper. Under these conditions, the separation factor Cu/Fe was obtained about 29.64. The extraction mechanism was studied applying the plot of log(D) – 2 pH against log [extractant] and it proved the association of two moles of Acorga M5640 for the extraction of one mole of copper. McCabe–Thiele diagram was constructed and a single-step extraction process was found to obtain themaximumextraction. Additionally, thermodynamic datawere investigated and the extraction process was endothermic and non-spontaneous at 298 K (ΔH = 27.05 and ΔG = 15.52 kJ mol−1). Moreover, the loaded organic phase was stripped and 80.94% copper was recovered after 20 min using 10% sulfuric acid concentration.

Jul 31, 2020

By N. O. Johnson

This is one of a series of-Information Circulars dealing with mining and milling methods and costs at mines in various districts in the United States. The Hog Mountain gold mining district is of the northern edge of Tallapoosa County, in the east central part of the State of Alabama. The district is equally close to Goodwater and to Alexander City, both stations on the main line of the Central of Georgia Railroad. From Alexander City the mine is reached by 13 miles of graded road, traveling in a northeast direction. In dry seasons the road is good; in wet weather it is bad but passable. Improvements are being made constantly on the road, so that in the near future the gravel road should be good under all weathered conditions.

Jan 1, 1936

By W. H. Bassett, C. H. Davis

The late J. P. Sparrow, chief operating engineer of the New York Edison CO., carried out a series of practical tests on condenser tubes of several copper alloys and reported on the results to the Association of Edison Illuminating Companies at its meeting in September, 1913. In the preparation of these tubes the senior author had the pleasure of cooperating. Copper-zinc alloys in the proportions of 60-40,70-30,80-20, 90-10, and Admiralty metal, which is in effect 70-30 with 1 per cent. of tin, were tried. Monel metal and several copper-nickel alloys, and 8, 5, and 3 per cent. aluminum bronze were also tried. At the time of this report, the aluminum bronze had been in service for 4 1/2 years and seemed to be giving especially good results but later it began to fail and showed no substantial improvement over Admiralty metal. Monel metal was unsatisfactory and the nickel alloys apparently did not give better service than the Admiralty alloy. Previous to the publication of the report, and after considerable discussion, it was agreed that a test where tubes of different kinds could be under laboratory observation would be advisable, so the apparatus described here was set up in The American Brass Co.'s Waterbury Laboratory. This was fitted with tubes of copper, brass, bronze, nickel silver, cupro-nickel and other alloys, and the test started on Oct. 11, 1912. Salt water from East River, New York harbor, was barrelled and transported to the laboratory for the test. A fresh supply, completely replacing the water in service, was obtained at the end of each six months period. Plan of Procedure In general, the procedure was to inspect the tubes at short intervals and to remove those that had begun to leak. The tubes removed were carefully examined and a photographic and microscopic record of the

Jan 1, 1925

By Tim M. Benson, Adam L. Lamanna, Carolina Martinez-Gutierrez, Mark J. Stephani

The Lower Concourse C Extension (LCE) 108-in Storm Sewer consists of a 2,797-foot long, 27 to 55-foot deep, 108-in I.D. storm sewer tunnel. Situated beneath active taxiways and a terminal apron at Hare International Airport (D), the tunnel diverts ows from existing storm sewers located within the footprint of a future satellite concourse. The project was delivered via Construction Manager at Risk (CMAR) as part of Chicago Department of Aviation’s (CDA) ongoing O’Hare 21 Capital Program. This paper presents project details, multiple stakeholder coordination, subsurface risks and challenges, TBM performance, and impacts to existing infrastructure.

Jun 23, 2024

By Hans Ruge

The El Soldado copper mineralization occurs as relatively high-grade irregular ore bodies with assay contacts and with frequent inclusions of barren rock. The sampling method must be timely for production grade control purposes, as well as accurate and inexpensive. Sampling techniques evolved from sampling dump cars at the haulage level to sampling scooptrams at the loading pockets. These were abandoned in favor of sampling production blast holes. Several sampling alternatives are discussed. These involve the selection of optimum volumes and sampling frequencies while taking into consideration geological parameters and statistical analyses of sampling data.

Jan 1, 1984

By Thomas T. Read

THE official title of our topic for today is "Resources of Metals and Other Strategic Minerals," but in accepting the invitation to open this discussion I claimed the privilege of being allowed to talk about problems other than resources for the two reasons that a great deal has already been said about resources and because we can never discuss them with the degree of certainty that an engineer likes. Resources are uncertain for many, reasons. One is that we do not know what is in the earth. It is four thousand miles to its center and although oil wells 1 ½ miles deep are becoming common and engineers are now talking of drilling holes 2 miles deep, even when they do they will have advanced only one two-thousandth part of the total distance. Only a relatively few mines are over a mile deep as yet. We know certainly that it is comparatively expensive to work at such great depth, but it would be a very foolish man who would assert it will be' impossible, one or two hundred years from now, for engineers to obtain from great depths mineral supplies that are now being obtained at or near the surface. As long as- I can remember I have been hearing that our petroleum resources were in imminent danger of speedy exhaustion, and yet the yearly output is now of the same order of magnitude as the total resources were once estimated, with ' the cry of over-production the loudest it has ever been. Tapping progressively deeper and deeper sources of supply, has produced this result. Even in the thin layer that we are now working much-exploration still remains to be done. .

Jan 1, 1929

By Yury Kapelyushin

Formation of cementite in the reduction of hematite by CO–CO2 gas was studied in situ using high temperature XRD (HT XRD) analysis. Reduction of hematite was examined in the temperature range 873–1173 K by CO–CO2 gas mixture with high carbon activity. When carbon activity in the system was 1.5, cementite was formed only at 1023 K; it was not observed in experiments at 973, 1073 and 1123 K. Formation of cementite was observed at 923–1073 K when carbon activity increased to 3–5; and at 873 K when carbon activity was 10. Formation of cementite at 973–1073 K proceeded through metallic iron; however, in the reduction of hematite at 873 and 923 K, iron was not observed; cementite apparently was formed directly from wüstite. XRD spectra were used to estimate concentration of carbon in austenite in the process of cementite fromation.

By William M. Bowron

THIRTY years ago, when I stood on the cliff of red fossil iron-ore, on Red mountain, Jefferson county, Ala., I asked what were the geological relations of this remarkable deposit. In reply I was told that it was a limestone colored and saturated by some unknown but wholly external influences, and that at a reasonable distance from the surface the color would disappear. I could find no satisfactory explanation either of the nature of this wonderful external permeating influence, or of the cause of such a ferrous impregnation selecting this one particular bed of limestone, to the exclusion of the higher and lower beds of the same material which are not even stained. I. THE PRESENT THEORY. Referring to this subject, Dana says:' "The clays, clayey sandstones and limestones of the Clinton epoch, through New York and the Appalachians, show that the mud-flats and sand-banks, and hence the shallow seas of the coast region, still continued. . . The beds of argillaceous iron-ore, which spread so widely through New York and some of the other States, south and west, could not have formed in an open sea, for clayey iron-deposits do not form under such circumstances. They are proof of extensive marshes, and, therefore, of land near the sea-level. The fragments of crinoids and shells found in these beds are evidence that they were, in part at least, salt-water marshes, and that the tides sometimes reached them." At first, this explanation seemed satisfactory, but the more I studied the ore the less satisfying the explanation became. 1. In the ore itself I found associated with the small particles of rounded matter (now consisting of iron oxide in which organic structure, if ever present, has become lost, though the

Nov 1, 1905

By ALICE V. Petar

Thallium is one of the rare metals that has come into commercial use within recent years . Its comparative scarcity , combined with a resemblance to the common metal lead , have retarded the development of uses for thallium . Although production is still measured in pounds rather than in tons , it is now finding application in a number of fields . Perhaps the earliest commercial use of thallium was as a constituent of optical glass of higher refractive power than similar glasses containing lead . One of the later applications to attract attention was the use of the oxysulphide in a sensitive electrical device similar to the selenium cell . The " Thalofide " cell , which was patented in 1919 , constituted for a time the most important outlet for thallium. During the next few years the limited use of thallium and its salts in other fields was insufficient to absorb an annual production of a few hundred pounds , and the price dropped from $ 16 or $18 per pound in 1922 to $ 5 per pound in 1924 . Beginning in 1925 several new uses were developed , especially as a poison for rodents and ants , and as a result the demand for thallium increased sufficiently to cause a recovery in price to the present level of from $12 to $15 per pound .

Jun 1, 1931

By d&apos, I. J. Agati

The stockpiling and reclaiming of bulk materials can be a challenging task for engineers seeking the optimum solution for plant needs, reliability, and at lowest unit cost. The objective of this paper will be to expose advantages, disadvantages and limitations of many storage and reclaiming systems to the responsible engineer and management. The paper will emphasize the practical aspect of stockpiling and reclaiming methods. Many valuable and interesting papers are available dealing with the theoretical viewpoint and application of a particular manufacturer's machine. Several of these are mentioned in the bibliography. As many practical parameters as possible will be given. After twenty years in the field of designing and selling bulk materials handling systems, the needs of the user and the plant are recognized and reasonably understood. This paper cannot give solutions to all problems In this vast field but will stress practical applications and examples of various installations. The evolution of advancements in materials handling is based upon not only technological innovations, but learning from many experiences of others and utilizing them as stepping stones to improved installations.

Jan 1, 1969

By Jeffrey Shawn Peterson

The testing procedures of the u.s. Mine Safety and Health Administration specify that intrinsic safety acceptance tests be conducted using a standard tungsten-cadmium electrode configuration in the break-flash apparatus. However, in realistic mining environments, other materials may be more likely sources of sparking. Information defining the probability of spark ignition between common materials such as aluminum, brass, copper, lead, tin, cold-rolled steel, and stainless steel is of more practical value in determining ignition hazards. The U.S. Bureau of Mines has completed an investigation of the influence of material on the ignition probability using the breakflash apparatus. By comparing ignition currents or ignition voltages corresponding to a probability of one ignition per thousand sparks to those found previously for cadmium, a margin of safety may be estimated for each material. This report presents the results of an investigation into the influence of disk electrode material on the probability of ignition.

Jan 1, 2010

By Sang Han Son

The vapor pressures of FeCL2 and ZnCL2 in the FeCL2?ZnCL2 system were measured by the transpiration method at 873K and 9I7K, The vapor pressure data were interpreted to indicate the formation of complex ions in the FeCL2?ZnCL2 melts, It is presumed that the complex molecule FeZnCl4 as well as FeCL2 and ZnCL2 exists in the vapors in equilibrium with molten FeCL2-ZnCL2 mixtures, The activities in the FeCL2-ZnCL2 system are shown a negative deviation from Raoult's law. These results suggest the formation of complex ions such as ZnCL14 in molten FeCI2?ZnCL2 mixtures.

Jan 1, 2003

By Arthur V. Petty

The Bureau of Mines has researched the utilization of mining and pro-cessing wastes as raw materials for the production of glass-ceramic pipe. Characterization of various wastes as to occurrence and chemical composition is reported. A computer program was developed and used to identify waste materials and mixes that would result in glass melts from which glass-ceramics could be produced after cooling and subsequent heat treatments. The production of abrasion-resistant pipe from inexpensive and readily available domestic resources could offer an economical substitute for high-alloy steels containing the critical and strategic materials cobalt and chromium.

Jan 1, 1984

By W. T. Culler

"The ""rate-of-preduotion curve"" described in the revised Treasury Manual* was devised by the author in May, 1920, and since that time has been use by the oil and gas valuation section of the Treasury Department in determining the rate of production of wells for purposes of taxation. This curve is most useful for estimating the future production of a well, or group of wells, of known daily settled production, where future-production curves and tables based on yearly production records are available. It also provides a means for determining the past year's production of a well of known daily settled production, or conversely, the estimated production on any day for a well of known yearly production.The rate-of-production curve is auxiliary to the production decline curve and is derived from it in estimating the future production of a tract, a production decline curve formed from the records of the tract itself should be used. If such records are not available, and there is no information which leads to the belief that the average production decline of the wells in this tract differs from the average for the pool or district, an average curve for the pool or district may be used.The accompanying chart illustrates a typical rate-of-production curve, with the yearly production decline curve from which it is derived. The production decline curve shown is for an average well in the Augusta district, Butler County, Kansas, and has been constructed from the tables given on page 128 of the revised Treasury Manual.The ordinate (vertical scale on the chart) of any point on a yearly production decline curve represents the production of the well during the year previous to the date shown by the abscissa (horizontal scale). For example, the chart shows that an average well, which produced 100,000 barrels of oil in 1915. produced 92,000 barrels in the year previous to January 19, 1916, produced 53,300 barrels in the year previous to June 1, 1916; produced 49,000 barrels in the year previous to July 1, 1916, 27,000 barrels in 1916, and 10,000 barrels in 1917."

Oct 1, 1921

The New Southern Railway (NSR) involves the excavation of approximately 10 km of single bore tunnel from Tempe Reserve, Tempe, to Prince Alfred Park (PAP). PAP is located just south of Central Railway Station in SydneyÆs Central Business District (CBD). From Tempe Reserve the alignment takes the tunnel under Sydney Airport including the main north/south runway. Sydney Airport is approximately 8 km south of the CBD. The NSR is being constructed by a private group, the Transfield Bouygues Joint Venture (TBJV). Transfield is a major Australian contractor and the French contractor, Bouygues, is providing the soft ground tunnel construction expertise and is also responsible for the design of the concrete segmental lining. This paper sets out to present in some detail the issues involved in tunnelling under the airport and in particular under the north apron, the main north/south runway and the new elevated roadway. The paper concentrates on these three areas on the airport with an emphasis on the following. The risks involved and measures taken to minimise the risks in tunnelling under the International Terminal north apron (with Jumbo Jets parked immediately above). Secondly, settlement predictions, settlement and runway operation criteria and the actual settlements that have occurred on the main north/south runway. Finally, the criteria that was developed during the construction of the deep bored piers for the elevated roadway at the Domestic Terminal as the TBM passed through this area of construction activity.

Jan 1, 1999

By A. Jolly, A. R. Kumar, T. Novak

"Coal dust in an underground mining environment has always been a health and safety issue, especially with longwall faces. Efforts to integrate a flooded bed scrubber within a longwall shearer are underway at the University of Kentucky (UK) in order to reduce worker exposure. Small scale physical modeling, along with numerical modeling and full-scale experimentation, are engineering tools being used by the authors for simulating operating conditions underground. Recent advances in affordable 3D printers offer a means for fabricating accurate, scale models for obtaining timely insights prior to building large, expensive test setups. Comparing scale-model results with those of numerical modeling, such as computational fluid dynamics (CFD), lends guidance and confidence in a proposed design. This paper discusses the small scale physical modeling of a longwall shearer with an incorporated flooded-bed dust scrubber in its operating environment. A tracer gas was used in the model in lieu of dust to measure dust-capture efficiency. Results obtained from the physical model are presented and compared with those of CFD model. The small scale model and the CFD results demonstrate good agreement. Dust capture results show the usefulness of the approach in advance of actual design implementation. INTRODUCTION Dust generation is an undesirable, but innate, byproduct of all mining processes. It is particularly problematic in underground coal mining, where coal dust poses potential hazards from two fronts – health and safety. Coal workers’ pneumoconiosis (CWP), commonly referred to as black lung, is a chronic lung disease that results from the long-term overexposure to respirable coal dust. Although the prevalence of CWP has steadily and significantly declined over the three decades following the Federal Coal Mine Health and Safety Act of 1969, a study by the National Institute for Occupational Safety and Health (NIOSH, 2008) indicates that significant health hazards associated with respirable dust still exist within the coal mining industry. In addition to being a health hazard, coal dust can also create a potentially catastrophic safety hazard. Dust that is not captured or removed at its source is suspended and transported throughout a mine by the ventilation airstream. This float dust is subsequently deposited on all mine surfaces along its travel path. Without adequate application of rock dust to these surfaces, forces from a localized methane ignition can reintroduce settled coal dust into the airstream creating an explosive mixture. Therefore, capturing and removing coal dust at its source mitigates the probability of two major hazards that continue to plague the mining industry."

Jan 1, 2016

By A. Lawson

"Continued and expanded use of underground diesel-powered equipment is considered desirable in order to achieve necessary production capability, particularly when coal becomes increasingly in demand as an energy source. Although diesel engines are derated for underground use, concern has been expressed in many quarters regarding the health effects of worker exposure to diesel-generated particulate and NOx emissions. This concern will increase as Canadian diesel fuel quality becomes heavier and with higher sulphur content. This could result in a requirement to increase ventilation rates by 50%.This paper describes the results of studies of various approaches designed to reduce diesel emissions. Two major approaches have been followed: fuel modification, and emission control hardware development. The results of progress in the development of these approaches will be described.Fuel modification includes the application of water/diesel and methanol/diesel fuel emulsions to the engine. Details of the techniques employed in this approach will be described, together with the effects on diesel emissions. (The paper is concerned with the emission aspects only, not the possible major engine modifications and/ or substitute materials of construction for 100070 methanol.) Use of methanol has the added advantage of acting as a diesel fuel substitute and extender, and there are expectations that underground diesel engines could eventually operate on close to 100% methanol fuel, thereby eliminating particulate emissions. The results of emission control hardware development will also be presented and will include the effects of catalysts, water scrubbers, exhaust filters and exhaust gas recirculation techniques on emissions. A combined systems approach employing a number of these components appears to be the most viable method of controlling the complete array of diesel emissions.This work should culminate in a better understanding of the costs involved in employing fuel modification or emission control hardware relative to the costs of increased ventilation which mpy be necessary to maintain a safe working environment for the underground worker."

Jan 1, 1981