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By John L. Ryon

Experimentation with ammonium nitrate fuel oil mixtures at three under-ground salt mines revealed its excellent applications at those properties. The author relates the present blasting practice used at these mines by the International Salt Co.

Jan 4, 1961

By Peter Haasen

INDIUM antimonide has the zincblende structure. A possible defect that does not disturb the indium tetrahedron surrounding any antimony atom in this lattice (or vice versa) is obtained when neighboring

Jan 1, 1958

By Bruce R. Lipin

Chromite, the only ore of chromium, occurs almost exclusively in mafic-ultramafic rocks and their weathering products. However, not all kinds of mafic-ultramafic rocks are favorable hosts for possible low-grade chromite deposits. For instance, chromium-bearing basalts are not favorable because they commonly contain <0.3% Cr203, and chromite is almost always less than 50 mp in diameter, if it is present at all. Chromite-bearing ultramafic rocks in stratiform and alpine complexes tend to be either ore grade (>25% chromite) or very low grade (<2% chromite); intermediate rocks are scarce. In most complexes, large tonnages exist only in the <2% chromite rocks and the composition of the chromite in those rocks may be unsuitable for metallurgical use. Some nickel laterite districts contain more than lo8 tons of material with 2.0 to 5.5% Cr203, and hence, chromium could be a byproduct of nickel in some laterite districts. In addition, some chromiferous sand placers may contain tens to hundreds of millions of tons of material between 2 and 5% Cr203

Jan 1, 1983

By Minoru Yamada, Eikichi Mohri

INTRODUCTION Most of the copper concentrates treated by the flash smelting furnace at Kosaka smelter come from "black ore" that is produced in the local mines nearby. The copper concentrates contain various impurities such as lead and zinc as shown below. [ ] These impurities are mainly concentrated into the flue dusts in the copper smelting system. The dust production rates of flash smelting furnace and converter at Kosaka smelter are, therefore, fairly high compared with other copper smelters. However, by recovering these valuable metals in the dusts systematically, profit-increase of the by-products must be expected. This also leads to the solution of environmental pollution problems and enables us to establish the technical completion of complex sulfide ore treatment by flash smelting process. HISTORY OF DUST TWATMENT AT KOSAKA SMELTER 1) December in 1967 to January in&apos; 1969 Since the flash smelting furnace started its operation in December 1967, all the dusts from the furnace had been recycled. Only conver-

Jan 1, 1976

By C. A. Stetefeldt

In a former paper (Runs., xxi., 286) I described the plant of the Marsac Refinery, and the manipulations of the process, but cou1d not, at the time, give reliable statistical results. To supply the latter is the object of the present paper. I shall give actual facts as correctly as possible, without any bias one way or the other. For all statistics I am indebted to Mr. W. G. Lamb, who has charge of the Marsac lixiviation-plant and refinery; to Mr. A. Luebeck, assayer at the Ontario mill; and to the Daly Office, Salt Lake City.* Before starting on the work of the year 1892, a most careful clean-up was made, and any remnants were charged to the refinery. During 1892 the Marsac lixiviation-works produced 48.8 tons of so-called "regular" sulphides, which contained, on an average, 11,449 ounces of silver per ton; 11.77 ounces of gold per ton; and 569.8 pounds of copper per ton. To this must be added, 266 pounds of sulphides and by-products left over from the product of 1891, which contained 1380 ounces of silver, 1.41 ounces of gold, and 63 pounds of copper. Before giving the results of the clean-up, a general discussion of the items of expense, methods of assaying, etc., is desirable.

Jan 1, 1895

By Robert Steinitz

Soft iron parts for magnetic applications, particularly pole shoes, constitute a major portion of the ferrous products of powder metallurgy. The residual pores in pressed and sintered parts reduce values such as the magnetic permeability but service experience extended over a number of years has proven beyond doubt that in many instances the lower density of powder parts is not prohibitive to their use as replacement of machined magnetic parts. The magnetic requirements for pole shoes, particularly the permeability, vary within wide limits, especially with the relative size of the air gap in the finished assembly. The overill permeability of an assembly, is given by the formula where is the permeability of the core material, I the total length of the magnetic path, and a the length of the air gap. Fig I shows the variation of the overall permeability with the permeability of the core material, calculated according to Eq I for an air gap of I pct of the total length of the magnetic circuit. It is readily recognized that to use core materials hav- A

Jan 1, 1949

By B. M. Andreas

PRIOR to 1934 all haulage of ore and stripping on the Mesabi Range was by rail. Early rail systems had small narrow-gage locomotives with correspondingly small dump cars. These trains were replaced with larger standard gage rail systems powered by steam locomotives ranging up to 224 tons in weight, which have in turn been replaced by diesel electric locomotives. Along with this development cars have been increased to 30-cu yd capacity. Improvement of cars includes alloy steel construction for lower over-all weight and use of roller bearings to decrease rolling resistance. Despite all of these developments, the total material hauled by rail on the Mesabi Range has decreased every year. Yet, this is no reason to believe that rail haulage is becoming obsolete. Its adaptation to small mine operation has become impractical, but in large mines where normal railroad grades are possible or where hauls to plants or dumps are long, rail haulage is still one of the most economical methods of transporting large quantities of material.

Jan 1, 1954

By D. R. Spink, D. N. Okuhara

Two reagents have been proposed for the commercial extraction of copper from leach liquors, namely LIX64N produced by General Mills Chemicals, Inc. and Kelex 120 produced by Ashland Chemical Company. Each of these reagents consists of an active extractant and an additive. In the LIX system, the additive improves the kinetics of the extraction reaction whereas for the Kelex system, the additive acts primarily as a third phase inhibitor. Equilibrium and kinetic studies have been conducted with both systems. In general, the Kelex system effectively extracts copper at a lower pH than LIX64N; furthermore, the rate of extraction with Kelex is considerably faster than with LIX which indicates that systems employing the Kelex extractants might also be able to employ agitated columns rather, than mixer- settlers which are absolutely necessary for effective extraction with the LIX reagents.

Jan 1, 1973

By H. B. C. Nitze

Monazite is a phosphate of the rare earths, cerium, lantha num, and didymium (Ce, La, Di)PO,. It also contains thoria (Tho,) and silica, which are present in varying percentages, probably as impurities.

Jan 1, 1896

Terminology Relating to Nonmetallic Elements in Metals. BY T D YENSEN AND C H HERTY, JR (Tech Pub 555, Metals Tech, June 6100 words ) The paper gives arguments for confining the term "gases in metals" to its proper sphere and recommends the name "nonmetallic elements in metals" as a general title of the subject dealing with: (1) nonmetallic elements introduced into metals unintentionally or for various specific purposes; (2) phenomena occurring in metals caused by non¬metallic elements It also recommends a classification of the subject in which "gases in metals" occupies a definite, logical place

Jan 1, 1935

Jan 1, 1949

By J. J. Scott

INTRODUCTION Rock mechanics theory needs to be applied to solve ground control problems, but in the final analysis the mining method and equipment which is used will be those which solve problems in a practical manner. Equipment and its inherent productivity and safety as supplied as "off the shelf" items by manufacturers often dictate the size of mine openings. Operators may tolerate falls of ground and associated hazards if productivity and safety problems are not too severe. In this whole process the costs of mining finally dictates just what system will be employed and what equipment will be used. True solutions to ground control problems sometimes require that the mine operator step back and totally rethink his problems. The true cost of accidents are often missed and hidden in overhead costs. Losses in production and accompanying profit are not fully considered, false economics, such as using inappropriate roof support devices, are undertaken at times when using the most expensive devices to totally eliminate accidents may be the best overall solution. Automation to remove the worker from the hazard area is often over- looked as the initial capitol expense to apply it may be high. Cooperation between mine engineers, mine operators, safety personnel, equipment suppliers, and government inspectors, both state and federal, is required to reach workable solutions that best meet the goals of all parties.

Jan 1, 1983

New Products Equipment

Jan 4, 1953

By Harvey S

After considerable experience in connection with the magnetic iron-ores at the South, especially in the Cranberry district of western North Carolina and eastern Tennessee, the writer was led into a thorough investigation of the magnetic separation of iron-ores, and, from this investigation, has gradually been developed a separating machine which it is the purpose of this paper to explain. Numerous United States patents have been issued upon machines for magnetic separation. Since the original patents date back to 1849, it is not possible to-day to establish broad claims upon the principles of electro-magnets as applied in such machines. Among these inventions there are certain types of separators which have very marked practical advantages over the others; and these successful machines, while varying radically from each other in their proportions and arrangements, are all based upon a principle originally explained in a patent which was granted in 1870, and which has now expired by limitation. The problem of practically separating iron-ores, as found in the mines, is very different from the separation of a purely magnetic substance from a purely non-magnetic one, since the crystals of magnetite, scattered through the ore-bearing rock, and sometimes collected in masses, are of very different sizes. The average size of the particles may be definitely ascertained for each mine, and the crushing- and screening-machinery may be adapted thereto, but there will still be a large percentage of very fine crystals which, in the crushing for the average, will not be broken apart from the gangue. If these mixed particles are thrown into the heads they carry gangue with them, and if thrown into the tails they occasion a loss of ironore. There are two methods for preventing such loss. One is, to crush all the material to the size of the finest particles, which means, of course, a large crushing-plant, heavy wear and tear, and excessive cost for repairs, and the production of only a very fine-grained concentrate which our blast-furnace managers, to say the least, do not

Jan 1, 1893

By A. P. Coldren, V. Biss

SINCE the r ? a transformation rates of many carbon-free ferrous alloys and low-carbon alloy steels are relatively fast, conventional equipment is not suitable for the dilatometric determination of continuous cooling transformation diagrams. On the other hand, a method based on metallographic analysis of quenched specimens would not be practicable because the various products of shear-dominated transformation are essentially indistinguishable in low-carbon iron-base alloys. Both problems may be avoided by a thermal analysis method employing gas quenching of small specimens austenitized in vacuo. The laboratory equipment employed in the present study consisted of a Tektronix Type 564 Storage Screen Oscilloscope and a Kinney high-vacuum evaporator, modified as shown in Fig. 1, to permit heating a small specimen and cooling it slowly by programmed cooling or rapidly (up to about 8000°F per sec) by a controlled quench with helium gas. The oscilloscope records the electromotive force of a 40-gage (0.003-in.-diam) Chromel-Alumel thermocouple in the specimen during cooling. The temperature at which the cooling curve begins to show the influence of the heat produced by the phase change in the specimen was arbitrarily taken as the transformation-start temperature.*

Jan 1, 1970

By Ray Schmidt

When your committee approached me for a talk on "Mechanics of Secondary Metals Collection," I replied that this subject would probably not be very interesting to a group of engineers and requested permission to dwell on the Westinghouse Salvage Setup. I will attempt to avoid duplicating the points covered by Mr. Bliven. The Westinghouse Electric and Manufacturing Co. has main manufacturing Divisions in 25 cities and 9 different states, scattered throughout the country, as well as Naval Ordnance Plants in two midwest cities, and a Merchant Marine Turbine Plant, and two special War Production Plants in Eastern cities. You can, therefore, see that we must have a well rounded pro- gram with the entire respect and sponsorship of the various Division Managements. That was not so easy to get. Management has been a great deal like the general public in the past. I am sure most of you can remember the not very ancient day when each town had a ragman who had a horse and wagon and went through the streets of the town, from door to door, picking up what scrap he could accumulate. He was known as a junk man, and indeed, with the exception of the very last few years, the attitude of manufacturing management was: "We have a job to do. We have a product to manufacture. We don&apos;t have time to bother with the junk business."

Jan 1, 1943

By John B. Pearse

IN order to get an idea as to the strength of steel rails, it will be well to review the tests to which iron rails have been subjected. In England, Mr. Ashcroft found that the best 80 pound rails broke under a 300 pound weight, falling 15 feet. In Germany the Society of Railway Managers determined on and have long applied a test of 1000 pounds falling 101 feet, as the standard which all first-class iron rails must reach. In this country no inspection nor test is applied, but tests made show that iron rails from our most reliable makers, break under a 6 foot fall of a 1500 pound drop as an extreme test, most of those tested breaking under a far less test; some breaking with less than a 3 foot fall of the same weight. Everywhere where steel has been used, engineers have come to the conclusion that some test is required to show the regularity and strength of the product. As compared with iron, the tests which steel will stand are wonderful. After numerous experiments partially based on the experience of the rail-mill at Graz, belonging to the Southern Railway of Austria, the Society of German Railway Managers fixed upon a test of 2000 pounds falling 13 1/2 feet. They found that this test represented the steel which suited their necessities, and also found that with steel of otherwise average purity, this test represented about one-half per cent. of carbon, and made it a rule to take no steel containing under three-tenths of a per cent, of carbon, because it was too soft. They expressed a hope that a harder steel could soon be made tough enough to stand the same test. In England, a test was adopted of 2240 pounds, falling 15 to 17 feet on the rail on heavy bearings. This test has been found satisfactory under heavy traffic on average road-beds, and has been invariably

Jan 1, 1873

By K. Osseo-Asare

LIX63 In combination with DNNS selectively extracts nickel and/or cobalt from acidic leach liquors with pH values as low as 10 Nickel/cobalt and cobalt/nickel selectivities are achieved by varying the relative concentrations of LIX 63 and DNNS Increasing LIX63 concentration retards both extraction and stripping rates while DNNS has the opposite effect. Slope analyses of equilibrium data Indicate that both LIX63 and DNNS are present in the extracted complexes. Examples of possible flowsheets are presented.

Jan 1, 1981

By C. W. Purington

Jan 1, 1900

Executive Committee Board of Directors L F Reinartz, Chairman, H DeWitt Smith, Vice-Chairman, T B Counselman, M L Haider, Philip Kraft Finance Committee Board of Directors Andrew Fletcher, Chairman, A B Kinzel, D Wilson Endowment Fund "X" G F Moulton, Chairman, Erle V Daveler, &apos;55, Philip Kraft, &apos;56, I Brigden, &apos;57 Honorary Memberships W M Peirce, Chairman, &apos;56, M L Haider, ex officio, Andrew Fletcher, ex officio, John M Lovejoy, &apos;55, D H McLaughlin, &apos;57, Henry Krumb, &apos;58, L F Reinartz, ex officio Investments Erle V Daveler, &apos;57, Chairman, W M Peirce, &apos;55, Henry Krumb, &apos;56, G F Moulton, ex officio as Treasurer, Andrew Fletcher, ex officio as Chairman Finance Committee Local Section Appropriations A B Kinzel, Chairman, M L Haider, W S. Cumings, Fred J Meek

Jan 1, 1954