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Jan 1, 1938

By Edward I. Salkovitz

RECENTLY a set of crystallographic angles for bismuth was calculated and a standard (111) projection was constructed. Since these calculations

Jan 1, 1957

By A. A. Smith, J. S. Smart, A. J. Phillips

The preparation of a sufficient quantity of high-purity copper for extensive laboratory use in the study of impurity effects has been an integral part of a research program in progress at the Central Research Laboratory of the American Smelting and Refining Co. for the past several years. Initially the degree of purity desired was that necessary to meet two essential requirements for experimental accuracy: (I) no impurity was to be present in the copper in an amount capable of producing a detectable effect on the properties to be studied, (2) even the minor changes in propertties caused by the addition of extremely small amounts of individual elements were to be measured without significant interference from contaminants. In the course of the investigation, evidence has accumulated to justify the conclusion that this copper is of exceptional purity; in fact, no impurity can be detected by any chemical method or spectrographic technique known to the authors. The present paper describes the method of production of the copper and presents some of its properties. Preparation oF High-purity Copper The elimination of impurities from commercial electrolytic copper is accomplished by a three-step purification process. The first operation consists of an electrolysis through a purified CuSO4-H2SO4 electrolyte using bagged anodes, low current density (5 amp. per sq. ft.) and low tem- perature (25°C max.). The electrolyte is prepared from commercial Cu2SO4 and is purified by heating the solution and adding I gram Fe as Fe2(SO4)3 to each 100 grams dissolved copper; sufficient hydrated oxide of copper, prepared from Cu2SO4 and NaOH, is supplied to precipitate Fe(OH)3, which carries down arsenic, antimony, tin, selenium, tellurium and other minor constituents. Silver and remaining traces of lead are removed by addition of Na2S to the acidified filtrate, which is then reatered after standing hot overnight. The cold solution is made up to 30 grams per liter Cu and 150 grams per liter H2SO4 and introduced without addition agents into the electrolytic system, which consists of a double row of hard-rubber battery boxes with the inside webbing and partitions removed, arranged in seven steps of ascending height. Electrolyte is uniformly supplied to the two highest cells by glass siphons operating from a constant-level reservoir, and flows by gravity through the bank of seven cells, entering each at the bottom and leaving at the top. Glass air lifts continuously supply the returning liquid to the constant-level reservoir for recirculation. Each cell contains three 4 3/4 by 4 3/8 by 1-in anodes cast from high-quality electrolytic wirebar copper, various lots of which have been used with equal success. The anodes are pinned to sheet copper hangars shaped to prevent crawl of the electrolyte to the multiple-wired bus bars—which would result in fouling of the contacts—-and hang inside wool flannel bags stretched over open wood frames. The deposit

Jan 1, 1941

By A. J. Phillips, A. A. Smith, J. S. Smart

The preparation of a sufficient quantity of high-purity copper for extensive laboratory use in the study of impurity effects has been an integral part of a research program in progress at the Central Research Laboratory of the American Smelting and Refining Co. for the past several years. Initially the degree of purity desired was that necessary to meet two essential requirements for experimental accuracy: (I) no impurity was to be present in the copper in an amount capable of producing a detectable effect on the properties to be studied, (2) even the minor changes in propertties caused by the addition of extremely small amounts of individual elements were to be measured without significant interference from contaminants. In the course of the investigation, evidence has accumulated to justify the conclusion that this copper is of exceptional purity; in fact, no impurity can be detected by any chemical method or spectrographic technique known to the authors. The present paper describes the method of production of the copper and presents some of its properties. Preparation oF High-purity Copper The elimination of impurities from commercial electrolytic copper is accomplished by a three-step purification process. The first operation consists of an electrolysis through a purified CuSO4-H2SO4 electrolyte using bagged anodes, low current density (5 amp. per sq. ft.) and low tem- perature (25°C max.). The electrolyte is prepared from commercial Cu2SO4 and is purified by heating the solution and adding I gram Fe as Fe2(SO4)3 to each 100 grams dissolved copper; sufficient hydrated oxide of copper, prepared from Cu2SO4 and NaOH, is supplied to precipitate Fe(OH)3, which carries down arsenic, antimony, tin, selenium, tellurium and other minor constituents. Silver and remaining traces of lead are removed by addition of Na2S to the acidified filtrate, which is then reatered after standing hot overnight. The cold solution is made up to 30 grams per liter Cu and 150 grams per liter H2SO4 and introduced without addition agents into the electrolytic system, which consists of a double row of hard-rubber battery boxes with the inside webbing and partitions removed, arranged in seven steps of ascending height. Electrolyte is uniformly supplied to the two highest cells by glass siphons operating from a constant-level reservoir, and flows by gravity through the bank of seven cells, entering each at the bottom and leaving at the top. Glass air lifts continuously supply the returning liquid to the constant-level reservoir for recirculation. Each cell contains three 4 3/4 by 4 3/8 by 1-in anodes cast from high-quality electrolytic wirebar copper, various lots of which have been used with equal success. The anodes are pinned to sheet copper hangars shaped to prevent crawl of the electrolyte to the multiple-wired bus bars—which would result in fouling of the contacts—-and hang inside wool flannel bags stretched over open wood frames. The deposit

Jan 1, 1941

Jan 1, 1916

By Cleland N. Conwell

Reclaiming mined land in northern regions is less difficult than reclaiming semiarid lands. In 1972, the Usibelli coal mine near Healy, Alaska, initiated experimental plots to determine the proper grasses and amounts of fertilizer. The following spring, approximately 1600 acres of land disturbed by mining were seeded by low-flying aircraft. The reclamation project was evaluated by the State of Alaska and has been adjudged successful. The information gained is being used in reviewing prospecting permits and granting coal leases on state lands.

Jan 1, 1977

By W. E. Dunn

CHLORINATION of titanium ores and slags is the source of TiCl,4 intermediate between ore and metal. A number of chlorinators are operating in the United States using a wide diversity of ores. These chlorinators vary in design to accommodate the ore source, but all use chlorine and carbon.

Jan 1, 1961

By Young C. Kim, William C. Cassun

A proper economic analysis of pit slope design must reflect the trade-off between the benefits and the increased risk of slope failure inherent in steeper slope angles. This paper describes the results of a case study in which a newly developed probabilistic economic analysis procedure was applied to the selection of a pit slope design at a large porphyry copper mine in the southwestern U.S. The paper also demonstrates the availability of the required data such as the probability of failure schedule and cost of failure models, under "real-life" conditions.

Jan 1, 1978

By Y. J. Wang

A graphical technique by which the operating points for a two-fan ventilation system can be represented as the intersection of the modified fan curves is described. In constructing the diagram, the air quantities associated with the fans are considered to be independent variables and used as the axes of a rectangular coordinate system. The diagram may include, in addition to the modified fan curves, contour lines for resistances, pressures, and air powers. Procedures for drawing the diagram are discussed and illustrated with an example of the ventilation system.

Jan 1, 1986

By L. S. Deitz

This part of the symposium deals with the problems encountered by the consumer of nonferrous scrap, that is, the smelter and refiner who melts the selected scrap items and produces foundry ingots of specified compositions or billets for rolling or extrusion in nonferrous mills. The fundamental problems are quite similar for all secondary' nonferrous metals. However, these remarks will be confined to the copper-base alloys since in the sorting, melting and refining of these alloys probably all the usual types of problems are encountered; in addition, papers are being presented later on secondary lead, zinc and aluminum. While metallurgical

Jan 1, 1943

By Roshan B. Bhappu, Raul A. Deju

The mineral olivine has been the subject of continued research by various authors. Paik1 conducted infrared and flotation studies of the adsorption of sodium alkyl benzene sulfonates on olivine. These studies are of interest from two points of view. First, in the metallurgical field it is of interest to understand the mechanism of silicate flotation using sulfonate collectors and second, hydrologists are interested in studying the chemical reactions that take place when water plus sulfonates encounter a porous silicate medium. On the basis of his study, Paik was able to postulate a possible mechanism for the attachment of RSO3- (sulfonate radical) to the olivine surface.

Jan 1, 1973

By Lester F. Engle

Books have been written, complex charts drawn, great batches of punched cards handled by ever increasing numbers of computers, and innumerable meetings held-all for the purpose of making effective the ultimate objective of new, revised or improved process facilities. It is to the credit of management, engineers, and others that in the vast majority of cases, the outcome of their work has been technically sound and economically rewarding. There is a way, however, to insure even better results.

Jan 5, 1966

By M. J. Virnig, G. A. Kordosky, K. D. MacKay

LIX 34 liquid ion exchange reagent, one of a totally new class of metal extractants, is discussed in terms of its properties. Specifically, these properties include improved selectivity for copper and greater recovery. Some comparisons to the well known General Mill's LIX 64N have been made. Particular emphasis is given to treating solutions containing very low copper values and high impurity levels.

Jan 1, 1978

The 118th meeting of the Institute was under the auspices of the Institute of Metals Division and the Iron and Steel Section, and was held at Milwaukee, Wis. The opening session was a joint meeting with the American Foundrymen's Association and the American Malleable Castings Association, and was presided over by Benjamin D. Fuller, President of the American Foundrymen's Association. At this time Hon. Emanuel

Jan 12, 1918

By Zhengbo Pan, Fujun Gou, Jifei Chen

This paper discusses the various alternatives that are technically feasible for "over-the-raise" continuous advancing in gently inclined coal seams and the computer-aided selection of the optimal mining option. Examples in Wangshiao Coal Mine and Chaohua Coal Mine are cited to illustrate the interval between raises, face length, single or double raise layout and single or double face layout.

Jan 1, 1983

By W. A. Boyer

Mine hoisting ropes can be loaded to capacity only when the strength of each component is exactly known. Characteristic curves provide this information. When load and rate of acceleration are specified for an individual rope, the characteristic curve assumes a predetermined shape. The factor of safety is the value derived by dividing the breaking strength of the rope by the total stress on the rope where it goes over the sheave wheel. Total stress is made up of the weight of skip and cage, weight of ore, weight of rope between sheave and rope clevise or attachment, friction load, and acceleration force. Bending stresses are neglected in this discussion, as sheaves and drum diameters are assumed to be large enough to reduce these stresses to a negligible value.

Mar 1, 1956

By J. F. Pashak, T. E. Leontis

The effects of zirconium on the properties of sand cast Mg-rare earth metal alloys were discussed in detail in an earlier publication.' It was shown that a significant improvement in strength properties at temperatures up to 400°F resulted from the zirconium addition. In general, the properties of cast Mg-Didymium-Zr alloys were superior to the corresponding alloys containing Mischmetal and the optimum rare-earth level was approAmately 3 pet. Jessup, Emley, and Fisher have also shown the advantages of didymium in Mg-rare earth-Zr alloys, 2

Jan 1, 1961

By T. W. Martin, T. J. Crocker, J. M. Goris

The current technology of large rock conveyors is reviewed. Based on this investigation two large rock conveyor concepts have been developed and a test facility investigation designed and fabricated. The USBM will test these concepts along with loading and transfer points for handling mine run rock material up to 1.5 m (4.9 ft) in size. An evaluation of open pit mining systems using large rock conveyors documents substantial cost savings when compared to truck haulage.

Jan 1, 1983

By J. D. Livingston, Bruce Chalmers, R. L. Fleischer, R. S. Davis

INTERACTION of dislocations on intersecting slip planes has long been considered a primary cause of work hardening in metals. Easy glide and low work-hardening rates have been observed experimentally only when single-crystal specimens were oriented so that one slip plane was initially favored. When single-crystal specimens have been oriented so that initially two or more slip planes were equally favored, high initial work-hardening rates have been observed. In a polycrsstalline aggregate, glide on five systems is in general necessary for a crystal to deform in conformity with the change in the shape imposed by the other crystals.* Only a small fraction of the crystals of a polycrystal will be oriented so that two

Jan 1, 1958

By R. G. Robins

The processing of gold bearing sulphide minerals which contain arsenopyrite and various complex arsenic sulphides results in arsenic containing emissions and effluents which are suspect in relation to clean air and clean water standards. Removal of arsenic from gaseous emissions is briefly reviewed. The use of lime to stabilise aqueous residues as either calcium arsenate or calcium arsenite is shown to be inadequate for long term disposal since both compounds are converted into calcium carbonate due to the influence of carbon dioxide in the atmosphere. Mixed calcium arsenate-phosphate residues are similarly unstable, but present better stability than the straight calcium compounds. Alternative disposal methods are reviewed whereby the arsenic is converted to more stable compounds, such as barium arsenate, titanium (IV) arsenate, and arsenic sulphide.

Jan 1, 1984