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By G. M. Potter, J. B. Rosenbaum, Masami Hayashi

Most Japanese copper smelters are located in areas of concentrated industrial activity and high levels of atmospheric pollution. A review of unofficial sulfur dioxide emission control data from major Japanese smelters shows capture of 91 to 99.7 percent of the sulfur in the smelter feed. The bulk of Japanese smel ting capacity was constructed in the last 10 years. Six of the major sme lters use flash furnaces, and two use reverberatory furnaces. A prototype three-furnace continuous system is in use as a parallel train with reverberatory furnaces at one smelter. Most of the sulfur dioxide is manufactured into sulfuric acid. The remainder is captured by gas scrubbers that yield gypsum and sodium salts. Ready markets exist in Japan for the acid and other su lfur byproduc ts.

Jan 1, 1967

By William D. Riley

In order to evaluate the corrosion resistance of zirconium in mineral extraction processes, such as a clay-hydrochloric acid leaching process for extracting alumina, the Bureau of Mines conducted corrosion studies in HCl-AlC13-FeC13 environments. A series of weight loss and electrochemical tests were conducted at 25° and 65° C in aluminum chloride (AlC13) plus hydrochloric acid (HCl) solutions containing 0 to 1,000 ppm ferric ion. It was determined that zirconium, which normally exists in a passive state in chloride-containing solutions, undergoes pitting attack in solutions containing more than 100 ppm of ferric ion. It is also shown that an oxide film prepared in air at high temperature offers protection in acid solutions containing levels of ferric ion from 300 to 1,000 ppm.

Jan 1, 1981

By Wing G. Agnew

The drilling and bit-sharpening practice in the southwest Wisconsin zinc district generally conforms to the procedure described herein, except at very small properties, where drill steel is sharpened by hand. Though hot milling of rock-drill bits is practiced in South Africa on some of the large-scale operations, it is seldom seen at American minus in any form. Because of the simplicity and low cost of the equipment, it was thought that a brief description might prove interesting to same of the operators in ether districts who do not have enough steel to sharpen to warrant equipping an elaborate sharpening shop.

Jan 1, 1936

By R. L. Christie

"THE ISLANDS lying north of the Canadian mainland, and the large Boothia and Melville peninsulas, form one of the great archipelagos of the world; this sparsely vegetated and nearly unpeopled region extends about 1,500 miles east to west and 1,200 miles from the mainland to the northern tip of the northern-most island. Sea access to most of the islands is restricted by ice to the summer season, and the 'polar pack' ice of the Arctic Ocean presses the year round against the northwest margin of the archipelago. Although the region is remote, the accessibility has greatly increased through a network of weather stations, airfields and air routes connecting with southern centres.The area considered in this paper is that part of the island region underlain mainly by sedimentary rocks. In broad terms, this includes the land and sea areas of the archipelago and the adjacent continental shelf, but excludes the dominantly 'Shield' terrain of Baffin Island, and of Melville and Boothia peninsulas. An impression of the size and potential of this sedimentary region may be gained by comparing some areas: the land area of islands underlain mainly by sedimentary rocks is over 300,000 square miles or about 50,000 square miles greater than the area of Alberta. The total area of the region, including the continental shelf and the inter-island areas, may be double this figure, and may approximate one-seventh of the land area of Canada."

Jan 1, 1970

By Auã Kiahla, Tomi Kouvonen, Vinicius Miranda

Through numerical mathematical processing (Taylor’s approach and numerical derivation) the original data supplied by the accelerometer’s sensors was transformed into velocity and, after the data mining, a statistics residue analysis was applied in order to evaluate if the data from the prototype and from the traditional seismographs were similar. The data from each system was used to estimate the attenuation law and the results are shown in this paper

Feb 1, 2020

By H. L. Monroe

Meramec Mining Company, owned 50% by St. Joseph Lead Company and 50% by Bethlehem Steel Corporation,- is engaged in the mining, concentrating and pelletizing of iron ore from the Pea Ridge Mine which is located in the rugged, wooded Missouri Ozarks about 15 miles from the town of Sullivan or 75 miles southwest of St. Louis. The orebody was delineated in the middle 1950's by the St. Joseph Lead Company during the Company's intensive exploration program to discover new lead orebodies to replace the declining reserves of the famous Southeast Missouri Lead Belt. An airborne magnetometer survey was run by the U.S. Geological Survey, the Missouri Survey and several mining companies, (of which St. Joseph Lead Company was the principal supporter). The survey was published in 1950 and disclosed an anomaly in the vicinity of Pea Ridge. In 1950 test drill holes disclosed that under some 1300 feet of sediments there did exist an iron deposit of probable commercial significance. No further action was taken until 1956 when additional drill holes confirmed beyond reasonable-doubt-that this was a major iron ore discovery.

Jan 1, 1965

By R. W. Raymond

THE Brüclrner roasting-cylinder is well known as an apparatus which has done good work in the desulphnrization, particularly of refractory silver ores, in the western districts of this country. A paper by Mr. J. M. Locke, of Cincinnati, describing the cylinders, as constructed by Messrs. Lane & Bodley, in that city, may be found at p. 295, vol. ii., of the Transactions of the Institute; and a paper by Mr. N. H. Cone, vol. iv., p. 226, gives an account of their operation in Colorado. The purpose of the present paper is to present an .improved construction, designed by Mr. Brückner. This is clearly shown in the accompanying plate, which scarcely needs explanation. It will be seen at once that this construction involves two cylinders, instead of one. Mr. Brückner thinks that three cylinders might be better yet, as securing an exact mechanical reproduction of the work of the well-known three-hearth Fortschaufelungsofen, the most perfect of the reverberatories in which delicate roasting is performed with hand-labor. THE APPARATUS. Erection of the Cylinders.—Although the cylinders may he put lip at any locality, or added to existing works, it is preferable, if possible, to choose the site on a hill sloping naturally, say about 30' or 33. Two excavations are made, one 8 to 12 feet higher up than the other; and each is protected by a wall with a batter of about 1 inch to the foot, to prevent slides of stone and earth. Each cylinder being 20 feet long and 7 feet in diameter, the total excavation should be 60 to 70 feet along the hill, and 15 to 25 feet wide. On each level a building is erected 35 feet long by 20 feet wide and 12 feet high, with the roof containing a ventilator against the hill. When both buildings are on the same level, there should preferably be a solid frame-work of very heavy timber, to carry the four rollers which bear the upper cylinder. The four rollers carrying the lower cylinder should preferably rest on two very heavy pieces of timber, strongly braced together and laid to their top in a foundation made of stone or brick and cement. Foundations are necessary only under each two opposite rollers, but they must be made carefully,

Jan 1, 1886

By K. T. Audt

The Yayoi period, from about 300 B.C. to A.O. 300, represents a time of important changes in Japanese history. During this period the advanced rice culture of the Asian continent was introduced to Japan, along with the techniques of animal husbandry, spinning, bronze casting and metal working(1) . As was the case in the Jomon period (11000 B.C. to 300 B.C.), the Yayoi period is traditionally defined by a particular type of pottery, characterized by the use of the potter's wheel and an extreme simplicity of decoration and form(2) . Pieces of this pottery were found in 1884 in a district of Tokyo, known as Yayoi-Cho, not far from Tokyo University. Within a decade the name Yayoi had come to be used for the period which also saw the first casting of metals in Japan121. During the Yayoi period, the foundation of the ancient Japanese state was laid as the individual small communities were unified and as labour specialization and social levels developed. In fact, the Yayoi may be the true ancestral culture of Japan(3) . However, the origin of the Yayoi is not definitely known. One theory indicates that the Yayoi people may have been driven from the Asian mainland (via Korea) by the dynastic wars that accompanied the unification of China under the Ch'in and Han and that these settlers rapidly displaced the Jomon. Bronze objects and the cultivation of rice may have arrived about the same time - in the third century B.C. Iron was in Japan within another century, but since it rusts badly and disintegrates, only a few small pieces are known from such an early date(4) . After about 50 B.C., the Yayoi cultures of western Japan were in fairly close and regular contact with the continent via Korea(5)

Jan 1, 1999

By Hans Ehdwall, Erling Strandon, Friedrich Steinhäusler, Victor A. Leach

INTRODUCTION The basis for any measures in radiation protection is the quantitative assessment of the radiation exposure. Due to the extensive requirement in health physics manpower and related cost it is necessary to develop certain criteria regarding the necessity of monitoring and the selection of population groups to be monitored. Depending on the overall objective of the particular programme, the specific requirements for the measurement of atmospheric levels of radon, thoron and their daughters for practical radiation protection purposes differ significantly for those in the case of research applications, such as use of data for epidemiological studies. As part of the OECD-NEA Programme on Radon Dosimetry and Monitoring Task Group 1 reviewed available models for lung dosimetry in the case of inhalation of radon 222, radon 220 and their daughters (James et al., 1981). Using defined reference atmospheres for underground- and open-pit mining conditions as well as for dwellings, normalized conversion factors were calculated for the mean bronchial dose (mGy) per Working Level Month exposure (WLM). Task Group 2 discussed the features and adequacy of the Working Level (WL)-concept as a physical correlative of the absorbed lung dose and its limits of confidence and accuracy (Johnson and Leach, 1981). The WL-concept was found acceptable for radiation protection purposes provided that modifying factors like particle size, unattached fraction and respiratory minute volume did not cause the effective dose equivalent per WLM as calculated by either the James-Birchall or Jacobi-Eisfeld lung models to be more than 50 % above that given by ICRP of 0.01 Sv/WLM. For application in epidemiological studies the WLconcept is considered acceptable if the calculated absorbed dose to the tissue does not vary by more than 50 % (at the 95 % confidence level) from that given for defined reference conditions. In the following, objectives and requirements for the measurement of radon, thoron and their daughters are discussed for operational health physics routine and special research applications according to the scheme outlined in Fig. 1.

Jan 1, 1981

The underwater explosions have been used for several decades for the determination of energy content of explosives. This test method is the only one by which shock, fly rock and total energy can be measured separately. It enables to develop the energy content of explosives for different purposes; the military high explosives should contain more shock energy whereas the fly rock energy is very important feature for the blasting explosives. The purpose of this study was to establish a test place for the underwater experiments in an old water filled open pit, to estimate the repeatability of the energy measurements, to calculate the standard deviations and to compare the total energy content of commercial explosives to the theoretical values calculated by the thermo dynamical program. The test method seems to work quite well especially for the homogeneous explosives. The difference between the energy content of theoretically calculated and measured values for the homogeneous emulsion explosives was about -3% and for the dynamite about -5%. The energy difference for the unhomogeneous ANFO was detected to be -19%. The diameter of the charge was 15 cm and it was obviously too small for ANFO to detonate ideally. On the basis of the test results this test method seems to fit best for the cap sensitive, completely homogeneous, spherical charges whose masses are big enough and which are initiated from the centre of the charge. The underwater explosions as a test method is the only one which can separate shock, bubble and total energies from each other and therefore makes it possible to develop the properties of explosives for different purposes which is very important feature of this method.

Jan 1, 2005

By Clarence O. Babcock

This Bureau of Mines publication presents guidelines for mining near surface and underground bodies of water. The guidelines were based on information developed under contract in three phases of study, as follows: (1) Collection and documentation of data from worldwide sources; (2) application of existing guidelines, foreign, Federal, and State, to case histories of previous inundations; and (3) development of recommended guidelines for underground coal mining near bodies of water aimed at maximum efficient utilization of underground coal resources consistent with minimizing inundation hazards. While the contract guidelines were for the mining of coal seams, they may also be used for mining any tabular sedimentary mineral deposit. Tables are given for the determination of the size of coal pillars needed; for other bedded deposits, similar tables could be determined based on their strength properties.

Jan 1, 1977

By Alen Shibu Joseph, Arvind Rajnarayan Singh, Mudila Dhanunjaya Rao, Kamalesh K. Singh

In this article, the cementation of major impurities from zinc sulphate leach solution by the addition of zinc dust was studied by considering different parameters including time, mesh size, and percentage of excess zinc dust. The output obtained from various experiments was utilized for the design of experiments. A multi-level categorical factorial design with a quadratic model was employed during this study. Results were predicted to minimize the concentration of impurity metals in the solution by altering the parameters. Furthermore, these predicted results were validated by performing another experiment. Successfully, it showed that the predicted and experimental data values were close to each other. The predicted optimized values were 40 min, 100% excess zinc dust, and 300 mesh size for copper; 42 min, 100% excess zinc dust, and 300 mesh size for cobalt; 37 min, 100% excess zinc dust, and 300 mesh size for cadmium; and 34 min, 100% excess zinc dust, and 300 mesh size zinc dust for nickel. At these optimized values, the experimental results showed 99.99%, 55.7%, 99.6%, and 76.6% cementation efficiencies for copper, cobalt, cadmium, and nickel respectively. The statistical design of experiments for the effective cementation of impurities corroborates the economic feasibility of optimizing parameters for the proposed process.

Jul 18, 2022

By E. Goodwin

The mechanics of formation of wear-metal suspensions in lubricants is discussed, along with the relationship of the concentration of the metals and other particles to the wear of lubricated machinery parts. The importance of particle and suspension analysis of used lubricants in a preventative maintenance program is stressed, in particular with regard to mobile equipment in a mining operation.

Jan 1, 1978

By Paulo von Krüger

This paper deals with the cell design and operation of a tin electrorefining 1:5 pilot plant. The purpose of the work was the fitting of the basic parameters to be used in a full-scale tankhouse from a major Brazilian tin producer. The main specific difference was the use of permanent stainless steel cathodes instead of conventional tin starting sheets. The results of both product quality and operating parameters are discussed.

Jan 1, 2003

By H. B. Comstock

This paper reviews the trends in supply and consumption of the principal magnesium compounds in the United States in relation to domestic requirements and world resources. The data are confined to these principal magnesium compounds: Magnesium chloride, magnesium hydroxide, precipitated magnesium carbonate, and magnesium oxide (commonly referred to as magnesia). The properties and uses of magnesium compounds are shown in various chapters of' the 2nd edition of Industrial Minerals end Rocks. 3/ The third edition of this reference is in preparation. A more recent description of properties, uses and sources of magnesium compounds appears in a Bureau of Mines publication.4/ The American Iron and Steel Institute and the Refractories Institute have published comprehensive data on the properties and uses of basic refractories. Many magnesium compounds are prepared by the producers to meet specifications set by individual consumers.

Jan 1, 1960

By Arthur F. Taggart

TO all Mineral Dressers, but particularly to those in the Coal and Industrial Minerals Divisions: Ted Counselman, retiring after two years at the helm of the Milling Committee, pointed with pride to the continued growth of that committee, and sang the swan song "Why ain't we a Division of Mineral Dressing?" Our genial Secretary pointed out, handily, that, you see, the way the Institute is divided there are several blocks running across this way here, and one running all the way down here, and another running part way down here, and they all cut across each other like this, and anyway the miners want to be a Division now, so why not you Mineral Dressers be good and not upset the big Institute organizational chart? And anyway again, Divisions have vested interests, and a Division of Mineral Dressing would take something away from Coal and something from Industrial Minerals, and any good institutional man can see that a Division would never give anything up. It was all quite confusing, and apparently not too convincing, because then the Milling Committee went ahead and voted unanimously it is a good idea, let's see what the other fellows think about it as well.

Jan 1, 1944

By Ö Aydan

Rock dynamics is one of the most important topics in the field of rock mechanics and rock engineering. The spectrum of rock dynamics is very wide and it includes the failure of rocks, rock masses and rock engineering structures such as rock bursting, spalling, popping, collapse, toppling, sliding, blasting, non-destructive testing, geophysical explorations, science and engineering of rocks, earthquakes, and impacts. Undoubtedly, the rock dynamics issues in Mars would remain to be the same. Although mankind has no direct access to Mars yet, the Mars exploration rovers (Opportunity, Sprit, Curiosity and Perseverance), Mars Reconnaissance Orbiter and InSight Lander provided very valuable data so that some rock dynamics issues can be recognised. The author reports his considerations on rock dynamics issues in Mars from very careful examination of images and data provided from MERs and MRO and discusses their implications.

Nov 29, 2022

By Joseph Hamuyuni, Dmitry Sukhomlinov, Pekka Taskinen, Mari Lundström

The standard thermodynamic properties of the compound Ca2CuO3 were determined electrochemically by the Electromotive Force (EMF) method. The ternary phase Ca2CuO3 was synthesized from the pure oxides CaO and CuO at CaO saturation using a ceramic route. The EMF measurements were performed over a temperature range 973 T/K 1124. The standard Gibbs energy of formation of the ternary compound Ca2CuO3 was determined using the EMF technique as: DfðoxÞGCa2CuO3 ¼ 21:88422:92 103 T: ð1Þ

Mar 1, 2017

By Frank D. Lamb, Lloyg H. Baning

"The crushed-stone industry has long been troubled with the problem of producing a more or less cubical product for use as concrete aggregate. Its seriousness varies widely for each producer, depending upon the character of the rock employed for raw material and the ultimate use of the crushed stone. For many construction uses, such as the macadam or bituminous-concrete- type road, flat pieces are not objectionable and may even be preferable to more cubical rock. However, most specifications for concrete require that the stone must be reasonably free from flat and elongated pieces.The rigid specifications set by many contractors have resulted in the rejection of coarse aggregate that, except for the presence of an excessive amount of flat and elongated pieces, would be entirely acceptable. In many instances, if an efficient, economical method of removing flat and elongated pieces were available, local producers could meet the requirements of the contractor and thus eliminate the necessity for importing more cubical material.A brief investigation of the problem of removal of flat and elongated pieces from crushed aggregate, carried out at the Eastern Experiment Station of the Bureau of Mines, indicated that it is mechanically possible to remove flat pieces from crushed rock.TEST EQUIPMENTA number of mechanical devices are used by the coal industry for separating slate from coal; these depend upon the difference in shape of the crushed slate as compared with the coal. Such devices as shutter screens, spiral separators, and the Norman picker would be suitable for removing flat pieces from crushed rock in the same manner as they are used by the coal industry. None of these devices was immediately available for testing purposes, so an attempt was made to construct a simple device that could be used in commercial operations."

Sep 1, 1944

By W. G. Stevenson

With the author's background of extensive experience, this paper delineates the role of the prospector in modern-day exploration programs. The stages in the development of a prospect to a producing mineral district are outlined, and examples are given from the Ross River area of the Yukon Territory and the Peachland and Highland Valley areas of British Columbia.

Jan 1, 1970