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By D J. Kilkenny, D A. O’Toole, P B. Hills, K L. Seah

An investigation was undertaken to critically analyse the use of fibre reinforced shotcrete (FRS) for a variety of applications in large diameter shafts. Those applications included the use of FRS with or without the addition of subsequent rock bolting in the temporary support cycle prior to the installation of a permanent lining, most likely cast in situ concrete or as the final lining medium.Numerous authors have considered the early re-entry and strength characteristics of FRS in recent years. The current study has investigated the practical application of the recommendations of many leading authors in an endeavour to establish practical and acceptable risk-assessed procedures for the use of FRS for rapid, safe, efficient and cost-effective shaft sinking.Shaft sinking is regarded as a specialist and potentially higher risk activity due to the confined work environment, exposure to ground conditions and a high degree of manual handling associated with getting materials to the sinking face. The use of robotically applied FRS as a primary lining in shaft sinking has significant safety advantages in reducing manual handing associated with mesh safety support and bolting, as well as reducing direct exposure to ground conditions.The study involved both field testing and a literature review. The study established an initial set of criteria for the use of FRS in the development of large diameter shafts and demonstrated a number of scenarios where the technique of robotically applied FRS provided significant safety and cycle time advantages. The opportunity for a fully sprayed single pass lining was also investigated as part of the project.CITATION:Hills, P B, O’Toole, D A, Kilkenny, D J and Seah, K L, 2014. Exploring the use of fibre reinforced shotcrete in large diameter shafts, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 295–306 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By R. F. Al-Fariss

The phosphoric acid industry is expected to develop in Saudi Arabia in the near future. There are three main reasons for expecting this: the discovery of phosphate deposits in the Sirhan-Turayf region, the construction of phosphate fertilizer facilities of the TSP, DAP and NPK plants on the east coast of the country, and the availability of an ample amount of sulfur As a by-product from the petrochemical industries. This study is a part of the research work performed in the chemical engineering department At King Saud University to evaluate the Saudi phosphate rocks for the wet process phosphoric Acid production and to test different flotation methods for the carbonate rich phosphate rock In a laboratory scale flotation cell. Experimental results for the above tests, as well as Beneficiation by calcination, are presented.

Jan 1, 1993

By Haydn H. Murray

This paper presents the results of test work performed with a Pacific Electric Motors (PEM) high intensity magnetic separator (20 kilogauss) , a unit capable of separating weakly, as well as strongly, magnetic minerals in the particle size range of sands to clays. Tests were performed on some 40 industrial minerals. With some minerals excellent separations were attained and with others intermediate and poor separations were accomplished. This study is a preliminary survey and many of the intermediate and poor results can be improved as separation problems are worked out with additional test work. It is demonstrated that with a number of industrial minerals high intensity magnetic separation is a viable beneficiation technique that is economic ally feasible.

Jan 1, 1976

By F Mavroudis, M Gaastra

Due to the increasing demand for resources worldwide, efficient utilisation of raw material deposits and recycling technologies become more and more important. Growing industrial nations and increased living standards require a large raw material supply. Hereby responsible handling of existent primary and secondary raw materials is indispensable. By utilising state-of-the-art technologies resources are extracted, recovered and recycled more efficiently which increases sustainability. Hereby sensor technologies combined with intelligent data processing systems in particular provide a considerable research area. Innovative sensor technologies are already implemented during recognition of material-specific characteristics, during elemental recognition as well as during machine control. They are applied to attain increased automation levels of mining machineries, higher recoveries during mining and processing as well as higher recoveries. To be able to face the increased demand for sensor technologies and the integration into raw material industries, an interdisciplinary association of three RWTH Aachen University Institutes has been founded. The association has expertise on increasing productivity and capacity utilisations by automating mining and recovering processes by sensor technologies. Due to the utilisation of sensor systems, materials and structures can now be detected and elementary analysed on a real-time scale. The developed and enhanced techniques are the key for any ambition of autonomous plants and machineries. This paper gives an overview on the regarded sensor technologies for material recognition, machine automation and mineral processing. The authors present concepts based on extensive laboratory and field studies of successful implementation and application the technologies considering special mining conditions. Overall three applications are described to demonstrate the potential of sensor technologies for autonomous and sustainable mining: real-time analysis: recognition of elementary compounds during extraction processes; multi-sensor system EiControlPlus: designed for automation of longwall shearers by complete detection of the machineÆs environment; and sensor-based sorting: applied in recycling and mineralÆs industries.

Sep 26, 2011

By Charles A. Chase

This paper, descriptive of a single mine, is presented in the belief that it may furnish useful suggestions to mine-managers encountering similar problems; and it includes the details which will enable them to estimate the value of the methods employed—especially where these depart from common practice. Tt should be added, however, that this mine is not typical of the San Juan district, but differs markedly from neighboring mines in physical conditions and metallurgical requirements. The Liberty Bell mine is situated in San Miguel county, Colo., on the west front of the San Juan mountains, 2 miles north of Telluride. The vein was discovered in 1876 by Wm. L. Cornett, who, with subsequeilt locators, took up claims along the apex. A few hundred feet of development-work was accomplished, and a few? tons of ore were smelted or milled; but profitable working proved impossible under existing

Jan 1, 1912

By C. E. Shoenfelt

Operations ill Colorado oil fields in 1934 were not quite so extensive as in 1933, but much better results were obtained and one new oil field was discovered. In all, 26 wells were drilled, of which 9 were oil wells, 1 was a gas well, and 16 were dry holes. New oil production totaled 10,220 bbl. and new gas production totaled 33,714,000 cu. ft. This compares with new oil production in 1933 of 1238 bbl. and new gas production of 14,307,000 cu. ft. Dry holes in 1933 totaled 29 as conlpared with 16 in 1934. Oil was discovered in the Hiawatha gas field, Moffat County, in 1934 in the Mountain Fuel Supply Company's No. 4B Wilson, C. NE. NW. of sec. 23, 12N., 100W. This well was completed in a sand in the Wasatch (Tertiary) at 2304 to 2337 ft., after plugging back from 3797 ft. It made 20 bbl. of oil initially. No. 4B Wilson is the first well in the Rocky Mountain region to discover oil in commercial amounts in rocks younger than Cretaceous, and while it is not expected that Hiawatha will develop into an oil field of important proportions, eventually it may produce a considerable amount of oil as the gas pressure declines. The Hiawatha gas field was discovered in 1926, on one of six structures in what is known as the Vermillion Creek gas area. It is a northeast-

Jan 1, 1935

By Newell G. Alford

Forecasts of future timber consumption in soft-coal mining are handicapped by the lack of adequate experience records for estimating properly the timber requirements of the industry. Data were obtained from plants where records are kept or from operators who collected the information and to these were added composite figures for the continental United States in 1905 and 19191 and for central and western Pennsylvania and for Illinois in 1922.2 The result, representing slightly over 928,000,000 net tons, is shown in Table 1. Some of the companies furnishing data were unable to segregate the timber into classes of use but for those who did, Table 2 shows the board feet of posts and cross ban used per ton of coal mined and the percentage of the total timber consumed that was used in roof support. The wide variation in amounts of timber per ton of coal mined is the result of

Jan 1, 1924

By Bernard N. Moore

At present the demands of the United States for strorltium are met by imports from Germany, England and Canada, which vary considerably in proportions of ore and finished salts, in tonnage and in value. Statistics for the period 1926-1932 are given in Table 1. Domestic deposits arc known in many states, but the larger and purer ones are in the West, particularly in the desert region of southeastern California and western Arizona. These deposits are large enough to command interest, particularly in consideration of future cheap power at the Boulder Dam. The deposits described in this paper were examined during an investigation of the mineral resources of the Boulder Dam region by the United States Geological Survey for the United States Bureau of Reclamation in the spring of 1934. Mr. D. F. Hewett, who had general charge of the investigation, Mr. W. T. Schaller and Mr. M. I. Goldman contributed many helpful suggestions. Mr. N. H. Harshman assisted efficiently during the field work. Celestite Deposits The celestite deposits described in this paper are of sedimentary origin and Tertiary age. They are widely scattered, as shown on Fig. 1,

Jan 1, 1935

By R W. Wilson, F H. von Glehn

With ever-increasing energy costs and the modern focus on system efficiencies, the practice of æventilation-on-demandÆ is gaining momentum. Several examples, ranging from paper studies to practical examples have been recorded and another recent case study is presented here to encourage the practice. In comparison, æcooling-on-demandÆ has received far less attention. This paper explores the possible merits of this practice by investigating the theoretical response of cool intake airways and the thermal interaction between the air and the rock, in order to gain a better understanding of the system behaviour and to quantify the possible savings. A case study is presented that demonstrates the improvements that can be achieved. Recent developments that allow live interaction between ventilation network models and on-line monitoring systems, have the potential for intelligent active control and alarming of ventilation and cooling networks. This will facilitate and maximise the benefits to be derived from ventilation and cooling-on-demand.

Jan 1, 2005

By M. Bourgon

The conductivity of liquid copper sulfide has been measured as a function of the mole fraction of sulfur in the melt at three temperatures: 1170°, 1250°, and 1300°C. The results show that a) the conductivity of copper-rich Cu,S is independent of the sulfur pressure in the furnace, and b) the conductivity of sulfur-rich copper sulfide increases rapidly with sulfur pressure. Assuming that the band theory is applicable to liquids leads to the conclusion that copper-rich copper sulfide is an intrinsic semiconductor, in which case electrons act as carriers. The activation energy for conduction in this case has been calculated to be 0.7 ev. On the other hand, sulfur-rich copper sulfide behaves as a p-type semiconductor, positive holes being responsible for conduction. IN order to elucidate the structure of Liquid copper (1) sulfide, Derge, Pound, and Osuchl have studied the electrical conductivity of this compound as a function of temperature. Their results showed that the conductivity is rather high, of the order of 100 ohm" cm", and that the temperature coefficient of conductivity is positive. This high conductivity seemed to indicate electronic rather than ionic conduction. This conclusion was checked further by Derge, Pound, and Yang,2 who measured the current efficiencies of copper sulfide melts at various temperatures. In all cases, the current efficiency was found to be nil, indicating the absence of appreciable ionic contribution to the conduction in

Jan 1, 1958

By E Christodoulou, L Zoumpoulakis

The kinetics of the thermal decomposition of MgCO3 was investigated using isothermal experiments performed in a thermogravimetric analyzer under a nitrogen atmosphere at 380¦, 400¦, 450¦ and 480¦C. The weight loss data as a function of time were modified to give the fraction that reacted (ß) and the rate of reaction (dß/dt) vs. time (t). Kinetic analysis of the experimental results, using three different methods, showed that diffusion predominates the MgCO3 decomposition over the investigated temperature range, with the data being best fitted by JanderÆs equation ([1−(1−ß)1/3]2=kt). The activation energy was estimated by Arrhenius plots using both the initial reaction rates and rate constants from fitting the above equation. The values estimated were 27.1 and 171.4 kJ/mol respectively.

Jan 1, 2001

Coal Division Industrial Minerals Division Minerals Beneficiation Division Mining, Geology and Geophysics Division Elmer A Jones, President President-elect Will Mitchell, Jr, Past President J B Morrow, Eastern Regional Vice-President G Donald Emigh, Central Regional Vice-President J D Forrester, Western Regional Vice-President R B Ladoo, Treasurer John Cameron Fox, Secretary AIME 29 West 39 St, New York 18, N Y

Jan 1, 1957

By John B. Knaebel

Hammer machines are now widely used for underground sampling and exploration. Their application to such work can be divided into two classes - sampling and testing with ordinary drilling equipment to shallow depths of 22 feet or less, and "long hole" drilling with heavy machines and special equipment to depths of as much as 250 feet or more. In the first category hammer drills are employed for either of two distinct purposes: first, as a means of checking the results of grab or cut samples or, in certain types of ore deposits, as a substitute for these methods; and second, as a method of sampling the ground 5 to 20 feet beyond existing faces and thus aiding in the control of stoping operations or in the direction of development headings, as the case may be. The deep-hole drill, in the second category, has proved to be a valuable adjunct to the old established methods of exploring, end developing ore, provided it is employed under natural conditions to which it is suited, handled by men thoroughly familiar with the technique of its operations, and used with its possibilities and limitations clearly understood.

Jan 1, 1932

CLEAR sunny skies that prevailed all through the 175th General Meeting of AIME were not the 1east of the details that resulted from the many months and man-hours of p1anning by the Southern California Local Section. Some 2600 persons left the 1953 Annual Meeting technically enlightened, having had a choice of over 300 papers presented by 400 authors to listen to, learn from, and criticize. During the meeting, Mike Haider turned over the Presidency of AIME for 1953 to Andrew (Drew) Fletcher.

Jan 4, 1953

Jan 1, 1902

By D. V. Carter, Dan C. Williams, Franklin M. Hackbusch

During 1939 little of consequence happened in East and East Central Texas in the way of oil discoveries. At the end of the year, there were 47 oil and gas fields in the district. Twelve other fields, 11 oil and one gas, have been abandoned. The ranking fields in order of the number of completions for the year were East Texas, Talco, and Rodessa (Texas portion). There were 511 oil wells (distillate wells included), 32 gas wells, and 257 dry holes completed in the district. Exploration, Discoveries and Extensions During the year, 113 exploratory wells were drilled, the same number as in 1938; four oil fields and one gas-distillate field were discovered. Perhaps the most important discovery, which has been named Barron field, was that of M. Samuel et al., No. 1 Barron in Limestone County. The wells in this field are of the gas-distillate type. Other than the Talco and Sulphur Bluff fields, which produce oil from the Paluxy sand (Upper Trinity), this is the first field on the Corsicana-Mexia fault zone to obtain commercial production from deeper Trinity strata. This "pay" is the Petit lime of the Lower Glen Rose of the Trinity group. The four oil discoveries were: Redland, Angelina County; Bazette, Henderson County; Rowe and Baker, Henderson County; and Marion County Shallow in Marion County. It is believed that the Bazette field, Navarro County, represents an extension of the Flag Lake field. For details concerning discoveries, extensions and important wildcat wells drilled during 1939 see Table 2. Production and Proration The district produced 175,053,729 bbl. of oil (distillate production included) which is a decrease of 4.0 per cent from the 182,369,484 bbl. (distillate production included) produced during 1938. The district's production for the year 1937 was 208,594,453 bbl. The East Texas

Jan 1, 1940

Henry Carlisle: This is June, 1961, and my friend Arthur Bunker is on the other side of the tape recorder. I, Henry Carlisle, am pursuing the hobby of chronicling the interesting parts of the mining careers and the lives of well-known mining engineers. Now, Arthur, supposing we skip, for the time being, where you were born and brought up, and start right in with where you went to school. Arthur Bunker: I graduated from Taft School and then went to Yale, Sheffield Scientific School, and took a course in electrical engineering. I was quite fascinated by higher mathematics and physics, and this offered more in mathematics and physics than any other one of the engineering courses at that time. The school was only a three-year course, and so I graduated from there in 1916.

Jan 8, 1963

By Corby G. Anderson

Today, with a stringent economic and environmental climate prevailing in the copper business, there is increased interest in evaluating new processing alternatives for production. Hydrometallurgical pressure oxidation of copper concentrates is one of the more viable approaches and several technological candidates have emerged. Of these, an overlooked but, ironically the first industrially proven methodology, utilized nitrogen species catalyzation in the oxidizing pressure leach system to produce copper via SX!EW. Given its many inherent process advantages, this may prove to be a feasible process alternative for the future. In this paper, the history of the system and its application to chalcopyrite concentrates will be outlined. In particular, a novel methodology for effective recovery of precious metals from chalcopyrite concentrates will be discussed. Finally, the perceived economics of this unique industrially proven process will be delineated.

Jan 1, 2000

By Eugene Coste

Although some of the observers who first paid especial attention to the occurrences of oil and gas in the strata (such as Hunt in 1859, Andrews in 1861; Winchell in 1865, Mendelejeff in 1876, Höfer in 1876, Minshall in 1881, and I. C. White in 1883) seem to have been impressed with the fact that oil and gas deposits were connected with the disturbances in the rocks caused by their upheavalll yet, with the exception of Mendelejeff, and possibly Andrews, these observers do not appear to have understood what is really the one essential factor in the occurrence of oil and gas in the strata: viz., the faulting, uplifting, fracturing, fis-suring, and jointing always accompanying even slight rock disturbances, and in certain districts (petroliferous provinces)2 allowing solfataric hydrocarbon emanations to force their way up from the interior and to reach and impregnate the porous portions of sediments subjected to the disturbances. Instead of this simple explanation to account -for the observed connection between petroleum deposits and rock disturbances, most of the observers mentioned above, and many others who have foliowed them on the same lines since, have entirely reversed the problem. To them, instead of the dissemination of gases from fissures into the sediments, it presented the accumulation and concentration, according to anticlinal or other geologic structures, of oil and gas originally present throughout the whole mass of the strata where they were produced by the decomposition or distillation of organic remains. Whether this important problem involves accumulation from sources within the strata themselves, or infiltration and dissemination from outside sources, may be easily determined if all preconceived ideas are put aside and the established facts only are considered. Physical Facts Sedimentary strata are composed of alternate beds of shales, sandstones, and limestones, most of which are sufficiently close-grained to

Jan 1, 1915

By F. D. DeVaney

Metallurgists and coal-washing engineers have used heavy liquids for years in studying the characteristics of ores and coal. By such means true separations can be made between the various specific-gravity increments in the materials examined. To use of heavy liquids has permitted determination of the possible grades of tailings and concentrates by specific-gravity methods on any particular size, and therefore the size to which the ore must be crushed to free the valuable material. The simplicity of float-and-sink separation and the high degree of efficiency attained in the laboratory are factors that commend the method for commercial concentrations.

Jan 1, 1940