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By J. VAN DEN BERC

Tin production and export from the Far East are still a long way off from the prewar figures. The Malayan Peninsula, which had a rather good start directly after the war largely because of stock piles found in Singapore and elsewhere, has since been hampered in the rehabilitation of its tin mines and dredging operations by material shortages and, more recently and more severely, by revolts and attacks of communist elements and gangster bands. These hindrances make working in the mines dangerous and form a daily threat against the valuable and highly vulnerable dredges. Contrary to the conditions in Malaya are those on the tin islands of Billiton, Banka, and Singkep-all in the Netherlands East Indies-where the Dutch have re-established peaceful relations with the population. Dutch efforts since the fall of 1945 have been rewarded by continuously increasing production, extension of production facilities, and return of moderate prosperity, complete safety, and all-out co-operation among the population ? native and Chinese ? to the benefit of all concerned.

Jan 1, 1949

By Gang Guo, Zhong Liu

"In response to an increasing demand of anchored structures for underground space and transportation infrastructure in China, an innovative underreamed ground anchorage system was created. The novel anchorage system has provided more efficient functions with higher capacity at lower cost, because of the enlarged cylindrical body (known as ECB) sealed in capsule at bottom of anchorage. This paper presents the detailed structure of innovative anchorage system and its special features. To investigate the bearing mechanism of new anchorage, we evaluate its performance and failure mode based on the experimental results, and also indicate its strain-hardening load-displacement relationship. Unlike the shaft anchorages, it is identified no overall failure to be found in soil surrounding the underreamed anchorage. More importantly, the anchorage capacity is governed by the base resistance, which takes more than 80% of total pullout capacity resulting from the contribution of ECB. Finally a case history of anti-floating project introduces the new combined construction approach and procedure, which has provided the contribution to the quality control and cost efficiency.INTRODUCTION AND BACKGROUNDThe construction boom over two decades in China has resulted in an increasing demand for underground space and slope stability. The infrastructures market requires the more efficient anchorage systems for retaining structures, resisting uplift forces and slope protection. The major concern focuses on gaining higher capacity and lower cost resulted from perfecting anchorage systems. There are three main anchorage systems designed to achieve the above objectives: ? single bore multiple anchorage system (Barley 1997), ? regroutable anchorage system (Smoltczyk 1991), ? underreamed anchorage systems (Xanthakos 1991). Generally, the concept ? comparing with the other two, can be more competitive due to its distinct advantages. To improve the performance and durability of ground anchorages under the complex geological conditions and diversified engineering requirements, a number of different underreamed anchorage technologies had been used, which included cone - shape anchorage described by Liao, Wu and Shu (1997) in Taiwan, Soilex anchorage developed in Sweden (Massarsch et al. 1997), Soletanche anchorage proposed in France, blasting anchorage used in Czechoslovakia (Hobst and Zajic 1986), jet-grouting anchorage innovated in Europe (Anon 1988), as well as deep mixing anchorage created in Japan (Cheng et al. 2000).The underreamed anchorage systems have the remarkable advantages compared to the shaft anchorage system. However, there are also some weaknesses inherent in the underreamed systems. For instance, the mechanical underreamed anchorage is unsuitable in sand or waterbearing ground, because the enlarged hole is easy to collapse, and it is hard to ensure the quality of anchorages. On the other hand, relying on the blasting in deep hole, the geometrical space and dimension of enlarged hole is uncontrollable, meanwhile, the continuous blasting operations may easily cause the serious ground deformation and the negative effects to the completed anchorages."

Jan 1, 1900

By C. K. Leith, W. J. NEAD

(Glen Summit Meeting, June, 1911.) . ONE Of the most significant developments in the iron industry in recent years has been the discovery and opening of enormous reserves of low-grade ore in eastern and northeastern Cuba. The two principal fields are the Mayari and the Moa, situated on Nipe bay, in the Province of Oriente. A less well-known district of the same type is that of Baracoa, at the east of the island, and another is in Camaguey province in central Cuba. In the comprehensive estimates of the iron-ore reserves of the world, published during the summer of 1910 by the International Geological Congress in Sweden,' these Cuban deposits are estimated at about 2,000,000,000 tons. Certain it is that the reserve is a large one. The Spanish-American Iron Co., the Juragua Iron Co. (Bethlehem Steel Co.), the U. S. Steel Corporation, and others have been active in this exploration.. The Spanish-American Iron Co. has established a port for the handling of these ores at Felton, has built a railway 16 miles to the ore-fields, and has opened up deposits for steam-shovel mining. Its expenditures have reached an aggregate of about $6,000,000 in preparation for the handling of these ores. Shipment of the ore to Sparrow's Point, Md., has begun and may be expected to rise to a considerable amount in the near future. The ore reaches this point at a cost per unit of iron considerably lower than Lake Superior ores, and the presence of a low percentage of nickel gives a desirable steel. It is not the purpose of this article to consider these ores from a commercial stand-point, but rather to discuss their-origin. If our conclusions are correct, they throw light on the character of the deposits which should have some commercial significance. 1 The Iron Ore Resources of the World, an inquiry made upon the initiative of the Executive Committee of the Eleventh International Geological Congress, Stockholm, vol. ii., p. 795 (1910).

Mar 1, 1911

By J. Drzymala, K. L. Wolters, T. Chmielewski, T. D. Wheelock, D. H. Birlingmair

Microflotation tests were conducted with a modified Hallimond tube equipped with a fritted glass disk and magnetic stirrer to determine whether the results would support an equation that predicts a linear relationship between particle size and the reciprocal of particle density in water for a specified flotation recovery in a given time. Data obtained with the tube for either hydrophilic or hydrophobic solids fit the equation satisfactorily. It was also shown that the natural flotability of molybdenite is somewhat less than that of elemental sulphur and that sodium dithionite is a good depressant for sulphurised pyrite. In addition, it was found that the untreated pyrite and galena used in the study were hydrophilic and did not float by particle-bubble attachment.

Jan 4, 1992

By John Newby, Ulf Gwildis, Fred Marquis

From the Brightwater Conveyance System in Seattle to the Second Narrows Water Supply Tunnel in Vancouver, BC, the design and construction of deep-lying tunnels in the Pacific Northwest often require the incorporation of deep portal shafts. Alluvium overlying marine and glacial deposits combined with the high regional seismicity is the common geologic setting. The latest example illustrating the development of shaft design for this scenario is the 40-m-deep shafts of the Annacis Island Wastewater Treatment Plant New Outfall System. The main components of the shafts include the initial lining, providing the excavation support system to be used for launching and receiving a 5-m-diameter TBM; and the final lining, designed to withstand all static and seismic loads and to remain viable for the intended design life. This paper presents design and construction considerations for these shafts against the background of and lessons learned from past project experiences.

Jun 13, 2021

By Frank L. Hess

BERYLLIUM is demanding more of the limelight, and the output of beryllium copper (containing 2% to~ 3 per cent of beryllium) seems to have grown 60 per cent above that of 1936, which was double that of 1935. There is increasing interest in beryllium-aluminum alloys and small quantities are being marketed at $50 per lb. for the contained beryllium. Other alloys also can be produced. Further price decreases for beryllium copper (now $23 per lb. for the contained beryllium) seem , possible and desirable. No difficulty has been experienced in obtaining beryl and a 'reserve stock has been built up. One supplier heretofore found reliable has offered to furnish 200 tons per month. Supplies during 1937 have come from the Black Hills in South Dakota, Colorado. India, and South America

Jan 1, 1938

By Barbara Rutter, Phillip Mulligan

This research investigates how changes in shock tunnel geometry affect the pressure versus time waveform. The Large Arena Test Simulator (LATS), which is composed of four different rectangular sections connected by three expansion sections, was used to determine how the changes in geometry affect the shock wave profile.

Feb 1, 2020

By Helênio Resende Silva Júnior

PT. Krakatau-POSCO coke making plant, located in Cilegon, Indonesia, is the results of the know-how and experience of Paul Wurth (PW) in coke making field. The plant has a capacity of 1,321,000 t/y of gross coke achieved by two coke oven batteries with 42 top charging Paul Wurth “Jumbo” ovens each. PW “Jumbo” oven with a useful volume of 78,92 m3 allows decreasing drastically the number of pushing/charging operation per day with a consequent reduction of the diffuse emissions. Gas treatment plant with a capacity of 88000 Nm3/h has been designed in collaboration with DMT GmbH & Co. KG, adopting the latest technologies with specific design know-how. PT. POSCO-Krakatau plant has been successfully commissioned and started-up in October 2013. The present paper will highlight the main technology features applied in PT. Krakatau-POSCO project for both coke oven and gas treatment plants.

Aug 17, 2017

By S. Banisi, A. Ghasemi, E. Nematollahi

Discrete element method (DEM) has been used as a popular simulation method to verify designs by visualising how material will flow through complex equipment geometries. Although DEM simulation is a powerful design tool, finding a DEM model which includes real material properties (e.g., shape, cohesion and friction coefficients) is not computationally feasible. In order to obtain more realistic results, particle energy loss due to rolling friction has been highlighted by many researchers. To implement a reverse torque to account for rolling friction, various models have been proposed. On account of the complexity of the problem, there is no unique model for all applications (i.e. dynamic and pseudo-static regimes). In this paper, an in-house developed DEM software (KMPCDEM ©) was used to assess the robustness of three commonly used models by comparing the repose angle of iron ore pellets obtained through the draw down test in a laboratory setup and then the elastic–plastic spring dashpot model was modified based on considering the individual parameters instead of relative parameters of two contact entities. Results showed that the modified model could produce higher repose angle. The modified model was used to calibrate DEM simulation of repose angle of iron ore pellets in a laboratory setup of the draw down test. Comparison of the calibrated DEM simulation and laboratory results showed 2° differences between the predicted and measured angle of repose. This difference was attributed to considering the particle shape effects by assuming a spherical shape for particles. Keywords: DEM, rolling friction,particle shape, repose angle

Jan 1, 2020

By Ann Hubbs, Vincent Castranova, Jane Y. C. Ma, De-Hwa Chao, Joseph K. H. Ma

AN OVERVIEW OF THE ACTION OF TETRANDRINE ON SILICOSISBecause of the persistent presence of silica dust in the lungs silicosis is a progressive and irreversible disease. At present, there is no proven effective therapy for silicosis. Limited choices of therapeutic intervention with corticosteroids and other immunosuppressive regimens 1,2 have been accepted for some forms of pulmonary fibrosis. These treatments are only minimally effective, and the results provide little understanding of the disease state due to the lack of correlation between drug activity and the mechanism of fibrosis. Thus, continuing effort must be made in the search for effective antifibrotic agents, which may be used to provide a sequential analysis of the fibrotic process and to open the door for further research and clinical development. Tetrandrine is one of hundreds of drugs screened for antifibrotic activity by Chinese scientists. It has been used in China as a treatment for silicosis in open clinical trials3 and in laboratory animals. The action of tetrandrine on pulmonary fibrosis has been attributed to its ability to inhibit particle stimulation of alveolar macrophages, a key cell type central to the fibrotic process, to release oxygen radicals and inflammatory cytokines. Alveolar macrophages (AM) residing on the alveolar wall, are the predominant phagocytic cells of the lungs responsible for pulmonary defense against inhaled microorganisms and other particles and thus play an important role in maintaining the homeostasis of the lungs. 7 Ample evidence suggests that cells of the monocyte-macrophage series play an important role in the immunopathogenesis of pulmonary fibrosis. When upregulated by silica, alveolar macrophages generate reactive oxygen metabolites8·9 which can damage lung parenchyma and release fibrogenic growth factors and cytokines, 10,11 such as interleukin 1 (IL-1), which can induce fibroblast proliferation and collagen synthesis. The cytokine-mediated fibroblast proliferation and collagen synthesis are key steps in the development and progression of pulmonary fibrosis .11 Previous studies by our group have shown that tetrandrine exhibits strong binding affinity to AM and inhibits particle-stimulated respiratory burst activity (oxygen consumption, superoxide anion release, and hydrogen peroxide secretion) in these cells. 13 In addition, studies by Kang et al. 14 have reported that tetrandrine inhibits silica-induced release of fibrogenic factors such as IL-1 which are capable of inducing fibroblast proliferation and collagen synthesis. Reist et al. 15 further suggested that the antifibrotic action of tetrandrine may be mediated in part by the direct effect of this drug on the ability of fibroblasts to respond to proliferative agents. These results indicate that the mechanism of silicosis involves activation of AM and fibroblasts by silica, resulting in abnormal collagen production due to miscommunications between the cell types. Tetrandrine may interrupt this process by direct interaction with the lung cells.

Jan 1, 1998

By Patrick D. McLaughlin, C Fordham

"The project outlined in the accompanying paper was to densify beach sands on the pond side ofa tailings dyke to the strength required for future dyke construction, This was to be achievedthrough the detonation of relatively small explosive charges in the sand to cause settlement intoa denser state."

Jan 1, 1992

By D. L. Blakeman, Trimble. J. W., S. W. Banning

Noranda's Grey Eagle mine and mill, in the Siskiyou Mountains of northern California, began shakedown operations in the late fall and early winter of 1982. This paper describes some of the unique features in mineralogy, milling, and water treatment operation at Grey Eagle. In addition, major start-up problems in the mill and water treatment plant are discussed along with measures taken to correct these problems.

Jan 1, 1986

By Gary L. Simmons

Noranda's Grey Eagle Mine and Mill, located in the Siskiyou Mountains of Northern California, began shakedown operations in the late fall and early winter of 1982. This paper describes some of the unique features in mining, milling and water treatment operation at Grey Eagle. In addition, major start-up problems in the mill and water treatment plant are discussed along with measures taken to correct these problems.

Jan 1, 1984

By Kavanagh M. E, Henley R. W

The Meekatharra mining district lies in the northern pan of the Murchison Province of the Archaean Ynlgam block of Western Australia. Since dis- covery of the Paddy's Flat belt in the district in 1897 total gold production has been 67 tonnes and a further 33 tonnes in resources have been defined by drilling. The Paddy's Flat gold deposits occur within the Gabanintha Formation, a basal formation of the Murchison greenstone sequence containing komatiitic basalts, ultramafics and minor banded iron formations. The regional control on the distribution of deposits is an anastomosing shear belt which extends over 350 km and incorporates the Mt Magnet, Reedys and Meekatharra deposits. The following gold deposit styles may be recognized based on lithological association and alteration: Albite porphyry hosted, Carbonate-fuchsite- quartz alteration hosted deposits, Banded Iron Formation hosted sulphide replacement gold deposits and quartz vein deposits. With the exception of the banded iron formation hosted deposits, the Paddy's Flat alteration zone shows strong similarities to the alteration styles at Kerr-Addison (Ontario).

Jan 1, 1991

All the TECHNICAL PUBLICATIONS and CONTRIBUTIONS published in 1940 are available at Institute headquarters, unless otherwise noted. They are also on file in many public, university and technical libraries and, when so indicated in the list, may be found in the TRANSACTIONS. TECHNICAL PUBLICATIONS in Classes A-Metal Mining, B-Milling and Concen-tration, H-Industrial Minerals, and I-Mining Geology are distributed in MINING TECHNOLOGY, which is issued every other month. Technical Publications in Classes C-Iron and Steel Division, D-Nonferrous Metallurgy and E-Institute of Metals Division are distributed in METALS TECHNOLOGY, which is issued twice quarterly. TECHNICAL PUBLICATIONS in Class G-Petroleum Division are distributed in PETRO-LEUM TECHNOLOGY, which was issued quarterly in 1940 but will be issued every other month in 1941. TECHNICAL PUBLICATIONS in Classes F-Coal Division, J-Mineral Industry Education Division, K-Mining Administration, and L-Geophysical Methods of Exploration are issued as separate pamphlets. An Institute member is entitled to one copy of any TECHNICAL PUBLICATION or CONTRIBUTION. Copies of TECHNICAL PUBLICATIONS listed have been mailed to members of the Institute accord-ing to their registration by classes. CONTRIBUTIONS and other TECHNICAL PUBLICA-TIONS will be sent upon request. A member may purchase an additional copy of a TECHNICAL PUBLICATION or a CONTRIBUTION at one cent a page; minimum charge, 25¢. Nonmembers may purchase any CONTRIBUTION or a TECHNICAL PUBLICATION of the F, J, K, or L classes at the same rate, but the nonmember price per copy for METALS TECHNOLOGY, MINING TECHNOLOGY or PETROLEUM TECHNOLOGY is $1.25 domestic, $1.35 foreign countries. TECHNICAL PUBLICATIONS (separate pamphlet form), $2 per annum domestic, $2.50 foreign. METALS TECHNOLOGY, $7 per annum domestic, $7.80 foreign (Iron and Steel Division and Institute of Metals Division ferrous and nonferrous papers). MINING TECHNOLOGY, $6 per annum domestic, $6.60 foreign (metal mining, milling and concentration, Industrial Minerals Divi-sion, and mining geology papers.) PETROLEUM TECHNOLOGY, $6 per annum domestic, $6.60 foreign. Bound volumes have been mailed to members that have requested them, and MINING and METALLURGY is mailed each month. A member is entitled to one volume a year on his membership and he may purchase for $2.50 one copy of a volume not already received; additional copies of the same volume, $5. Nonmembers may pur-chase the volumes listed, at $5 each, plus 60 cents for Canadian or foreign postage. Extra single copies of MINING AND METALLURGY, 25¢ current issue, back numbers 50¢ each to members; to nonmembers 506 current issue and $1 each, back issues. Subscription price to nonmembers and to members for extra copies, $3 per annum domestic, $4.00 foreign.

Jan 1, 1940

By T A. J Hopper, S Mukkisa, M L. Johns, K T. O’Neill

Technological advances the sensor design and performance for logging while drilling (LWD) instrumentation offer considerable opportunities in iron ore exploration. Here we focus on the development of a nuclear magnetic resonance (NMR) LWD tool. NMR is an advanced geotechnical logging technology capable of providing in situ measurements of the porosity, pore size and permeability of the formation of interest. The ability to provide real-time characterisation of iron-ore systems is beneficial to both drilling operations as well as real-time formation evaluation. The development of an NMR LWD tool for mineral exploration drilling has previously not been achieved due to the significant technical and environmental challenges associated with the design and operation of such a tool. The tool outlined in this work is designed to work in reverse-circulation (RC) drilling systems. As such, the tool needs to be compatible with the RC drill-string, as well as being highly robust to survive the shocks and vibrations experienced during RC drilling operations. The magnetic physics of the probe must be capable of measuring at the appropriate depth into formation whilst being subject to the array of motions experienced during drilling operations. Furthermore, conducting accurate NMR measurements in an iron ore formation is challenging and the measurement methodology must be tailored to characterise the magnetic environment. The tool also requires high-powered electronics capable of operating the necessary pulse sequences for excitation and acquisition. The resultant tool design must therefore optimise the inherent trade-offs which exist between the physical components (ie mechanical structure, magnetic components and electronic hardware) in order to operate appropriately whilst not hindering RC drilling operations. Current experimental analysis of the prototype indicates that the current probe design exhibits the required measurement specifications and is nearing field testing. Future work will look towards commercialisation of the instrument.

Nov 8, 2021

By Henry A. Wentworth

(New York Meeting, February, 1912.) ELECTROSTATIC separation of ores in its present form is generally known as the Huff' process from the name of Charley H. Huff, of Boston, Mass., through whose constant and persistent labors (with the invention of Clinton E. Dolbear as a basis) the successful commercial process embracing separative machinery and the various electrifying devices has been developed step by step, and the finances for the long period of development provided, and the method finally established and recognized throughout the world as an important and successful addition to the ore-dressing department of metallurgy. The permanent field-success of electrostatic separation began in 1908 with a 20-ton Huff experimental mill built specially for the purpose by the American Zinc, Lead.& Smelting Co., in Platteville, Wis., a plant which was a success from the start and was gradually increased in capacity as the market-conditions warranted to 100 tons of concentrates per day. Much credit is due to the above-mentioned company for its initial venture, and for its assistance in applying the process to field use. Prior to 1908 electrostatic separators had been installed and operated (but for a comparatively short time, however) in a number of places; some under the patents of Mr. Dolbear by himself and associates, and some under the patents of Lucien I. Blake and Lawrence N. Morscher, by W. G. Swart, mining engineer, of Denver, who has always been a courageous advocate of electrostatic separation. Due to the difficulties experienced in the generation of the electrical charges, the primitiveness of the separators, the wooden construction instead of iron as at present, the lack of control of the electrical fields and other difficulties overcome by the later inventions of the Huff Electrostatic Separator Co.,

Jun 1, 1912

By Hormando Leocadio, CWM van der Geld, Julio Cesar Passos

Impinging water jets promote high heat flux extraction rate. Steel industry widely employs the process for accurate temperature control to improve the microstructure and to ensure adequate mechanical properties. The range of surface temperatures, heat fluxes and cooling rates are very large, which makes it important to obtain an accurate value of the heat transfer coefficient. This paper presents an experimental and numerical study of the heat transfer behavior of a high temperature (450°C - 900°C) steel plate cooled by a water jet at 20°C to 70°C. High-speed imaging (up to 20,000 fps) within water jet impingement zone allowed the characterization of the boiling regimes in the early stages of cooling. The effects of initial temperature, water jet temperature and velocity on the heat transfer coefficient were analyzed by inverse heat conduction method that predicts the heat flux and temperature on the top surface from temperatures measured with thermocouples inserted in test plate. Heat transfer is strongly affected by the initial temperature of the hot steel, water jet temperature and, less intensely, by jet velocity. High cooling rates start when liquid water is in direct contact with surface temperatures above 700°C.The results will contribute to the enhancement of the temperature cooling control on the runout table and cooling model employed at Usiminas Hot Strip Mill.

Oct 1, 2019

By E. C. Perkins, R. S. Lang, D. M. Taylor, H. Dolezal

The amenability of titaniferous slags and domestic mineral concentrates to chlorination was determined in a 6 - inch diameter fluidized bed chlorinator . Ilmenites from Valley County , Idaho ; Aiken , S.C ,; Trail Ridge , Fla .; and MacIntyre , N.Y .; and a titaniferous magnetite from Iron Mountain , Wyo . , were used in preparing the slags . The domestic minerals tested were an ilmenite concentrate from Valley County , Idaho , and a rutile concentrate from Magnet Cove , Ark . A high - grade Australian rutile was used as a standard for comparison . The impurity content of the slags and minerals tested , which was the most critical factor affecting their performance , was dependent on the geographical source of the material . All of the materials tested were amenable to chlorination in a fluidized bed although some required special operating conditions . Titanium extractions and chlorine utilization were over 90 percent for most of the slags and the Australian rutile . The Valley County , Idaho , ilmenite performed well in the reactor despite its 34 percent iron content .

Jan 1, 1963

By E. C. Tarpley, R. A. Drogowski, R. F. Abernethy

Three of the test methods frequently used for the determination of moisture in the analysis sample of coal were employed in analyzing a series of coals ranging in rank from anthracite to lignite . For most coals , the variation between the three methods are within the tolerances allowed between duplicate determinations by the same method . The processing variables studied included atmosphere , flow rate of atmosphere , inert atmospheres , oven temperatures , heating time , exposure of the dried coal to laboratory air , and surface area of the test sample . Unless close control is kept on these variables , erratic results will be obtained .

Jan 1, 1964