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By W. G. Davenport

Chapter 6 examined autotherrnal smelting of pure chalcopyrite concentrate with 50 mass% O2-50 mass% N2 blast. It showed that production of 1500 K products with this blast requires: 181 kg of pure oxygen 337 kg of air per tonne, of concentrate. It also showed that the grade of matte produced with this blast is 58% Cu. This chapter re-examines autotherrnal smelting by asking: (A) WHAT COMPOSITION BLAST (MASS% 02 -MASS% N2), 298 K, WILL AUTOTHERMALL Y PRODUCE 65% Cu MATTE 1500 K FROM PURE CHALCOPYRITE CONCENTRATE? (B) HOW MUCH PURE OXYGEN AND AIR WILL BE NEEDED? These are important questions for flash? smelting because furnace operators usually want to send specific composition matte to converting. This chapter shows how a specified matte can be produced autotherrnally with 298 K oxygen-air blast. Later chapters show how it can be done with hot blast, hydrocarbon combustion, different concentrates etc.

Jan 1, 2001

By J. -M. Chautru

A geostatistical simulation of a typical mining site for polymetallic nodules in the North Pacific Ocean is presented. This is the first stage in the design of an industrial mining system. Two variables which have a major effect on the orebody's economic potential are considered, namely: the maximum slope of the ground inside a mining block of 50 x 100 m; and the average quantity of nodules on the same support. Two geostatistical problems have emerged in this study. The first is due to the lack of a change of support model for the maximum of a variable. A provisional solution, considering an experimentally accessible 'equivalent' support, is proposed. The second is due to a non-linear link between the two variables. To be able to take this into account in the simulation, we propose a new method based on the decomposition: X = E(X/Y) + Residue (X). Satisfactory results were obtained with this approach.

Jan 1, 1987

By G. R. Hopkins, E. M. SEELEY

The number of natural-gasoline plants has shown a consistent decline in recent years, but the total capacity has increased steadily. The number of completed plants, as determined by a survey as of January 1, 1932, amounted to 959. Previous surveys of January 1, 1928 and 1930 showed 1,155 and 1,035 plants, respectively. Of the total plants on January 1, 1932, 859 were operating and 100 were shut down, compared with 999 operating and 36 shut down on January 1, 1930. The material gain in the number of inoperative plants in the last two years was probably due to the severe decline in prices of 1931. The low prices of 1931, which were approximately 40 per cent below 1930, made it virtually impossible for the majority of the independent plants, or plants not owned by a large integrated company, to operate at a profit. Accordingly, the majority of the plants removed from the list in 1930 and 1931 were owned by companies which were engaged solely in the manufacture of natural gasoline. The total daily capacity of the plants on January 1, 1932, amounted to 11,387,000 gallons, an increase of 871,000 gallons, or 8 per cent, in the two years 1930 and 1931. That the total capacity of the plants has increased while the number of plants has declined is due to the fact that nearly all the plants constructed in the last five years have been large plants. During 1931 the average total daily capacity of the operating plants was approximately 10,600,000 gallons, while the average daily production amounted to 4,944,000 gallons. This indicates that the plants operated during 1931 at 47 per cent of their capacity, compared with 58 per cent in 1930 and 61 per cent in 1929. Although more plants have been dismantled in Oklahoma in recent years than in any other State, it continues to rank first in number of plants. On January 1, 1932, there were 238 plants in Oklahoma, compared with 145 plants

Jun 1, 1932

By J. G. Craig

This paper initially was to be on the design, construction and operation of the Lucky Friday mill. However, this subject has been pretty well covered in some of the mining publications in the past few years - specifically Mining Congress Journal for April, 1961 and Mining World for March, 1962- : In order to avoid too much repetition, we decided to present in this paper a comparison of the Lucky Friday mill constructed in 1959, and the Mayflower mill built by us in 1962. During the past three years Hecla Mining Company has constructed two relatively small mills: The Lucky Friday mill at Mullan, Idaho 750 T/day; and the Mayflower mill at Heber, Utah - 450 T/day. These mills were engineered, designed and constructed by Hecla, using principally our own personnel, with very little outside (contractor) labor employed. This paper presents a comparison of some of the interesting features of these mills, and where differences occur, it discusses the reasons for the various differences. It compares such points as the testing program, physical layout of the plant, construction costs, the grinding section, the flotation section, tailings disposal, metallurgy, recovery, grades, operating costs, etc. To help illustrate, and to compare these features, we will project pairs of slides showing each of the two mills. First a little background and history on the properties ---

Jan 1, 1964

By John C. Machisak

Employment and related injury experience of the coking industry in the United States for 1957 contained in this publication is summarized under three general sections: (A) General injury experience: Tables 1 to 9: Current and comparable statistics on operating data, number, frequency, and degree of severity of injuries and major accident agencies involved in the cause of Injuries. Data are presented for the industry as a whole, for each type of oven, and for the States in which coke was produced.

Jan 1, 1959

By D. Beneteau, L. Feldman, D. Milne, A. Hyett, G. Snell

"Behaviour of rebar bolts subjected to combined shear and bending in underground potash mining applications is not well understood. An experimental investigation compared load applied to resin-grouted No. 25 metric rebar to theoretical load, calculated using elastic bending theory. Distributed optical sensing (fibre optic) technology allowed axial strain measurements at 1.25 mm increments along the length of rebar. Experimental procedure, data processing methods, and equipment improvements are needed for field applications of optical sensing technology. Goals were to adopt procedures for instrumenting rebar bolts, conduct tests, and develop data interpretation methods to measure field deformations and loads. ¦ KEYWORDS Fibre optic, Potash mine, Rebar bolts, Transverse load testing RÉSUMÉ On appréhende encore mal le comportement des boulons d’ancrage pour barres d’armature soumis au cisaillement et au cintrage pour un usage dans des mines de potasse souterraines. Une étude expérimentale compare la charge appliquée aux barres d’armature de diamètre n° 25 (25 mm en mesure métrique) enduites de résine époxy à la charge théorique, calculée à l’aide de la théorie de la flexion élastique. La technologie de détection optique distribuée (fibre optique) a permis d’effectuer des mesures de la contrainte axiale à des différentielles de 1,25 mm sur toute la longueur de la barre d’armature. Pour des applications sur le terrain de la technologie de détection optique, il faut envisager une procédure expérimentale, des méthodes de traitement de données et une amélioration de l’équipement. Les objectifs établis consistent à adopter des procédures d’instrumentation des boulons d’ancrage pour barres d’armature, à effectuer des essais et à mettre au point des méthodes d’interprétation des données pour mesurer les déformations et les charges sur le site. ¦ MOTS CLÉS boulons d’ancrage pour barres d’armature, essai par charge transversale, fibre optique, mine de potasseINTRODUCTION Resin grouted rebar bolts are commonly used in potash mines in the province of Saskatchewan, Canada, in areas where shear deformation is observed in the rock, or where potentially unstable ground is present, including locations such as clay seams. Opportunities to observe deformations of rebar, as shown in Figure 1, are rare because it is unusual in underground potash mining to excavate supported ground. In this situation, a block of potash containing a rebar bolt had failed."

Jan 1, 2019

By K L. C Gontalves

In 1999, the Mineral Development Centre of CVRD (CDM) acquired a flotation device referred to as Mini Pilot Plant (MPP), which is able to run continuous flotation tests with drill core samples. Since then this equipment has been used to define the flotation circuit and process conditions during the pre-feasibility phase of CVRDÆs copper sulfide projects. Until now, the MPP results had not been validated for an industrial flotation operation. The present work consists of a comparison and correlation of the results from a flotation MPP and an industrial plant. In order to make this comparison, an industrial plant was completely sampled and the feed ore was tested on bench scale and on a MPP. The metallurgical and mass balances of each test were used for the comparison.

Jan 1, 2005

By Wade L. Karlsen

"Revision surgery to replace joints in the human body requires materials that are strong, long-lasting, and biocompatible. Metallic implants made of cobalt-chromium-molybdenum alloys are already popular because of their proven corrosion and wear resistance properties, but there is an on-going effort to economically improve their performance. Alloying with inert nitrogen can enhance the mechanical properties of the alloy, enhance its corrosion resistance, and elevate the temperature at which the metallic implants can be thermally treated, without increasing the threat to the human body. The current work has produced a high-nitrogen Co-Cr-Mo alloy through HIP consolidation of metal powders that have undergone nitriding in a mechanically fluidized bed. The already fine microstructure of the powders combined with the increased nitrogen content resulted in significant property gains in the consolidated materials.IntroductionMetallic implants made of cobalt-chromium-molybdenum alloys are already popular because of their proven corrosion and wear resistance properties, but there is an ongoing effort to improve their performance. Research on a Stellite 21 cobalt-chromiummolybdenum alloy has shown that nitrogen alloying can be desirable from several standpoints [l]. Firstly, it has indicated that nitrogen can enhance the mechanical properties of the alloy, which could allow more demanding implant designs. The same work also demonstrated that nitrogen can elevate the temperature at which the metallic implants can be thermally treated, which is desirable in situations in which surface textures are to be sintered to the implant to enhance its fixation properties. Finally, that research work discovered that, not only does nitrogen not harm the corrosion resistance of the cobalt-chromium-molybdenum alloys, but it may in fact enhance it. Combining this with the fact that small amounts of nitrogen are not considered a threat to the human body, makes nitrogen alloying an attractive alternative for enhancing the properties of Co-Cr-Mo."

Jan 1, 2000

By A. A. McCloskey

APPROXIMA TEL Y 95 percent of Waite-Amulet's Lower A orebody will be mined by diamond-drill stoping. This method of stoping was developed, and has been successfully applied, at the Noranda mine in recent years(1) and is now used in several base-metal and gold mines in north-western Quebec and in other parts of Canada, South Africa, and Australia. The purpose of this paper is to deal with the features of the Lower A ore-body which led' to the adoption of this method of stoping, and in addition to give a general description of stope layout, stope development, main haulage development, chutes and grizzlies, diamond drilling for stope blasting, diamond drilling and equipment, primary blasting, secondary blasting, haulage and loading, ore pockets, pumping and drainage,. and shafts at Waite Amulet. Figure 1 is an isometric projection of the orebody, illustrating the mining system. The factors that led to the adoption of diamond-drill stoping of Lower A orebody are as follows: (1) Safety.0 (2) Size and shape of the orebody, and depth of the orebody below surface. (3) Strength of the hanging-wall, footwall, and sulphide ore. (4) Continuous ring-drilling from sub-level drifts, with no delay for blasting. (5) Large-tonnage blasts at the end of Saturday afternoon shift, after ali men are out of the mine. (6) Sub-levels may be retreated from top to bottom simultaneously, or lower sub-levels may be retreated first without any change in the ring-drilling la yout. (7) Large stopes up to 100 feet wide can be mined, leaving substantial pillars up to 60 feet in width, which may be partially recovered by âiamond~drill stoping or by other stoping methods. (8) A large tonnage may be drilled-off in advance of blasting, but only a supply of unoxidized ore for flotation treatment is blasted. (9) Better ventilation during working shifts. (10) Gravity flow of all broken ore to grizzlies located in the footwall of the orebody. (11) Electric blasting by a crew of two men.

Jan 1, 1941

The following list comprises the names of those persons who became members during the period of Mar. 10, 1918, to Apr. 10, 1918. ADAMS, NOAH- :.. Geol.,. E. N. Gillespie & Co., Box 1875, Tulsa, Okla. ALVAREZ, PEDRO Asst. Met., American Smelt. & Refin. Co., Blue Hill, Maine. BARTRAM, JOHN G., Pet. Geol., Roxana Petroleum Co. of Oklahoma, Cheyenne, Wyo. CHANEY, S. E Supt.., Arizona Binghamton Copper Co., Stoddard, Ariz. CLEVELAND, EARL C Mgr., Deadwood Min. Co., Mogollon, N. M. DENNIS, HOWARD B Min. Engr., Empire Mines, Grass Valley, Cal. FOWLER, ARTHUR A., Partner, Rogers, Brown &- Co., 30 Church St., New York, N. Y. FRIEDMAN, L. A Pres. and Gen'l Mgr., Rochester Mines Co., Lovelock, Nev. GUIBERSON, S. ALLEN, JR 923-24 1. N. Van Nuys Bldg., Los Angeles, Cal. KROHN, ARTHUR Mine Supt., Missouri Metal Corpn., Mine La Motte, Mo. KURSELL, H. A., Mgr., Altai Mines Ltd., Zmeinogorsk, Altai Gov't, Siberia, Russia. LANE, L. RAY Mine Examinations, Galiano 24, Aptd. 1066, Havana, Cuba.

Jan 5, 1918

NEW YORK LOCAL SECTION Executive Committee Louis D. HUNTOON, Chairman ARTHUR S. DWIGHT, Vice-Chairman THOMAS T. READ, Secretary, Woolworth Bldg., New York, N. Y. E. MALTBY SHIPP, Treasurer GEORGE F. KUNZ W. DE L. BENEDICT Meeting, Jan. 16, .1914 A meeting of the New York Local Section of the American Institute of Mining Engineers was held at the Engineering Societies Building, 29 West 39th Street, New York City, Jan 16 1914 the Chairman, -L. D. Huntoon, presiding. Forty members weld present. In the absence of the Secretary, C. A. Bohn was appointed Secretary pro teen. N. H. Darton, Geologist of the U. S. Geological Survey, delivered an address on. The Occurrence of Gas in Coal, illustrated by lantern slides of charts, curves, and tables showing various features of gas occurrences. J. W. Richards, J. T. Beard, W. L. Saunders, L. D. Huntoon, and Mr. Darton participated in the discussion which followed the address. THOMAS T. READ; Secretary.

Jan 3, 1914

By Qingqing Huang, Mohammad Rezaee

The Mineral & Metallurgical Processing Division (MPD) of the Society for Mining, Metallurgy & Exploration held the 12th MPD Student Poster Contest on March 2, 2022, during the MINEXCHANGE 2022 SME Annual Conference & Expo. The event showcased the work of 32 graduate and undergraduate students from U.S. and international institutions. The contest began in January when the students submitted one‐page abstracts for judging. In February, they prepared and presented posters that explained their research, and each student had five minutes to explain their research to a panel of judges during the conference. Recognizing the students’ efforts in working hard on their research topics and setting aside time to complete the necessary steps to enter the poster contest, the MPD provides monetary rewards to all participants. For graduate students, first place receives $1,000, second place $500, and third through seventh places $200 each, and for undergraduate students, first place receives $1,000 and second place $500. The main authors of nonplacing entries receive $125 each. Participation in the contest includes a free ticket to the MPD Luncheon, where the winners are announced.

Nov 22, 2022

By R. S. McClellan

In order to meet the ever-increasing demand by consumers for uniformity of ground talc, a new method of blending its finished product has been developed by Gouverneur Talc Company, Inc., at its plant near Gouverneur, N. Y. The method has been in use for a sufficient length of time to be now judged a success. The Gouverneur district is the leading talc producing area of the world, inasmuch as more tonnage is produced there than from any other state in the U.S. or, so far as is known, from any other locality in the world. Almost all of the output goes into industrial uses, with ceramics and paint being the principal consuming industries. The physical and chemical specifications imposed by these industries are stringent and the trend, as in most industries, is toward ever increasing severity. The blending method described herein has aided Gouverneur Talc to keep up with this trend.

Jan 3, 1961

C. H. WILSON,* New York, N. Y. (written discussion?).-On page 2680, under the heading Junction Box and Zone Box, the authors say, with reference to the zone-box principle of connections between primary couple, compensator couple, and copper leads, which method in its appli-cation to a single couple is shown in Fig. 34, that if this principle is adopted for a multiple installation, so as to save compensating leads; a selective switch may be (and the inference is that it must be) inserted between the zone box and the different couples, putting the switch at an inconvenient point, or putting up with some complicated interlacing of connections.. Wilson-Maeulen Co. has employed the zone-box method extensively for several years and in none of the many multiple installa-tions has either of those alternatives been resorted to. Instead there has been used a method of wiring with the switch at the indicator and involv-ing no more complications than the junction-box method shown III

Jan 11, 1919

W. H. PORTH, New York, N.Y.-I would like to ask what effect segregation of lead would have upon the corrosion of sheet zinc; also what effect would abnormal percentages of iron have upon the ductility of Sheet zinc? One of our difficulties seemed to be that the cells, when standing on the shelf, corroded. We have attributed this to local action in the zinc sheet. We would like to know whether the segregation of, these impurities in this sheet zinc will have any effect on the local action occur-ring in sheet zinc. Lately we have had difficulty in punching some sheet zinc, in that the sheets split in the die. The section that split seemed to have an abnormallly high percentage of cadmium and iron; would that cause it to become brittle? C. H. MATHEWSON.-Iron is one of the most unwelcome impurities when high ductility is the principal requirement in rolled zinc. High

Jan 12, 1919

By S. Subhawong

Following the startup of the zinc plant in Clarksville, Tennessee, in 1978, the original effluent treatment plant did not perform as designed. The sludge, produced in a conventional lime neutralization treatment, settled poorly and began to fill the permitted lined impoundment within two years, well short of the original design capacity. Another sludge pond had to be constructed. This led to a new process modification of the original design. Although the design is still based on the conventional lime precipitation of heavy metals, the current effluent treatment plant has evolved into a hydrometallurgical circuit, capable of producing good quality water without generating sludge. Undesirable elements are bled from the zinc circuit and are rejected through the effluent treatment operations. Wallboard grade gypsum is produced, instead of sludge, and all the gypsum is sold to cement and wallboard plants. This operation also recovers and returns more than 1,500 tonnes of zinc annually to the 105,000 tonne/y zinc plant.

Jan 1, 2000

BOSTON LOCAL SECTION Executive Committee HENRY L. SMYTH, Chairman ALFRED C. LANE, Vice-Chairman AUGUSTUS H. EUSTIS, Secretary-Treasurer, 131 State St., Boston, Mass. ROBERT H. RICHARDS ALBERT SAUVEUR Meets on the first Monday evening of each winter month Twenty-fourth Meeting The Twenty-fourth meeting of the Boston Local Section was held at the Exeter Street Theater, Boston, Monday, Jan. 4, 1915. The Chairman, Henry L. Smyth, introduced Mr. S. Le Fevre, of Mineville, N. Y., who presented an exhibit of moving pictures, illustrating the various operations of mining and milling iron ore as carried out at Mineville. Mr. Le Fevre pointed out, as the pictures were run off, the dangers of the various operations, and the precautions that should be taken to avoid or minimize these dangers. . After the exhibition of pictures, the members adjourned to the University Club, where dinner was served. At the close of the dinner and an impromptu recital by Mr. Weeks, the meeting was adjourned. AUGUSTUS H. EUSTIS, Secretary.

Jan 2, 1915

PHILIP L. GILL, New York, N. Y. (written discussion*).There is one feature of the fire-refining of electrolytic copper which I believe should be mentioned when the relation of oxygen content to the "pitch" or "set" of refined copper is under discussion; that is, the segregation of impurities. Variation of "pitch" or "set" is frequently noted in castings of different shapes, cast at the same time from the same furnace, though the oxygen content remains identical. For instance, it is possible to cast two wire-bars in the same shaped molds from the same ladleful of copper, the one 2 in. thick showing a good level set, the other, 4 in. thick, being overpoled. Also, when two bars are cast of the same weight and at the same time from the same furnace, one bar in a copper mold at the proper temperature, the other in a mold that has been allowed to get overheated, the bar in the hot mold will show

Jan 8, 1918

By J. A. Voigt

In an effort to determine the optimum conditions for preparing high purity, fine particle size high temperature superconducting oxide powder, we have investigated how calcination conditions influence the conversion of a chemically prepared hydroxycarbonate precursor powder to YBa2Cu307. We find that the precursor can be converted to phase pure YBa2Cu307 in either oxygen or synthetic air (20% 02. 80% N2) at 850°C. This temperature is substantially lower than the temperature (>900°C) normally used for the calcination of mixed-oxide powders. The lower calcination temperature prevents particle sintering and maintains the desired fine particle size. Powder processed in synthetic air shows a low degree of crystallinity indicating it may be more sinterable than the highly crystalline powders produced when an oxygen atmosphere is used. Intimate contact between powder particle surfaces and a flowing gas atmosphere promotes the reaction between the BaCO3 component of the precursor powder and the Y and Cu constituents.

Jan 1, 1989

By M. McChesney

Modern materials for underground support* by M. McChesney The properties required of a support material for underground tunnels are discussed and, because concrete is both economical and easy to apply, a number of new reinforcing materials for concrete are examined with particular reference to these properties. From about thirty tests on different types of reinforced concrete, it is concluded that the addition of polymer to a concrete does not seem to influence the concrete's post-failure behaviour, and the on'y benefit to be achieved by this addition is to increase its flexibility (or to decrease it, depending on the polymer). Steel fibres tend to increase both the strength and stiffness of the concrete, but polypropylene fibres, although having definite loadcarrying capacities, provide non-stable failure, also known as brittle failure. The best result was obtained for concrete reinforced with steel wire: the post-cracking strength was very good and was maintained for a considerable deformation.

Jan 12, 1976