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By Charles H. Hopkins, J. M. Lohr

A commercial development requiring a suitable alloy or alloys for sealing into various grades of glass made it desirable to have a more exact knowledge of the expansion characteristics of the nickel-iron alloys than appeared in the published literature. The expansion of the more common types of glass under consideration varies from 2.7 to 10.4 X 10-6 per degree Centigrade, over the range 20" to 400' C. For reference, the t,hermal expansion curves of several types of glass used for sealing by the lamp and tube industries are given (Figs. 1 and 2). This paper covers a detailed investigation of the thermal expansion of a series of nickel-iron alloys in which the nickel content varies from 30 to 70 per cent. Particular stress is laid on the alloys that contain between 40 and 55 per cent Ni.

Jan 1, 1939

By Charles H. Hopkins, J. M. Lohr

A commercial development requiring a suitable alloy or alloys for sealing into various grades of glass made it desirable to have a more exact knowledge of the expansion characteristics of the nickel-iron alloys than appeared in the published literature. The expansion of the more common types of glass under consideration varies from 2.7 to 10.4 X 10-6 per degree Centigrade, over the range 20" to 400' C. For reference, the t,hermal expansion curves of several types of glass used for sealing by the lamp and tube industries are given (Figs. 1 and 2). This paper covers a detailed investigation of the thermal expansion of a series of nickel-iron alloys in which the nickel content varies from 30 to 70 per cent. Particular stress is laid on the alloys that contain between 40 and 55 per cent Ni.

Jan 1, 1939

By ElRoy Nelson

WATER provides to many mineral industries functions similar to those performed by money in the economic system. Water is a medium of exchange. It is also required in chemical reaction for cooling, for transfer of minerals, and for cleaning. To a great extent, water is also a raw material in almost every industrial operation; it becomes a component of the finished product. In the Rocky Mountain region, water is treated with a great deal of respect. There has not been enough of it when needed. Long ago storage facilities were planned and devised to assure a supply during periods of shortages. This comes from the history of the region in irrigation and mineral processing. Within this region the shovel was always the most lethal weapon used in settling disputes over the use or misuse of water.

Jan 10, 1954

By Macelwane

WHAT characterizes a geophysical engineer and sets him apart from all other engineers? This is a question that is important not only for accrediting purposes but is assuming increasing importance in the licensing of professional geophysical engineers by state boards. What is the basis of distinction of one type of professional engineer from another type is answered in part by the need which brought each type into being precisely because that need could not be satisfied by pre-existing types and which nevertheless demanded the special outlook, training, and abilities of an engineer. The need which called for the civil engineer was the adaptation to the tasks of civilian life of the capabilities developed by the military engineer for the design and construction of roads, bridges, dams, earthworks, military buildings, and other structures and of mechanisms required by military operations.

Jan 4, 1954

By G. M. Ritcey

The design of the plant facilities together with the necessary equipment required for the operation is at an optimum only for the specified plant with its peculiar priorities and preferences. Because many alternatives in design are possible to suit a particular plant, each plant designer and contractor must choose carefully in the selection of the site, design and choice of materials of construction, as well as the type of equipment necessary for the process. Basic factors as efficiency, dependability, simplicity, and safety must be considered early in the construction; while the choice of equipment, materials of construction, possible corrosion problems, automation, maintenance, effluents disposal and tailings dam construction can greatly affect the plant costs. While existing plants are in operation, the know-how gained from the operating experience of those plants can be invaluable in the new plant planning, design, and construction.

Jan 1, 1978

By Charles H. Hopkins, J. M. Lohr

A COMMERCIAL development requiring a suitable alloy or alloys for sealing into various grades of glass made it desirable to have a more exact knowledge' of the expansion characteristics of the nickel-iron alloys than appeared in the published literature. The expansion of the more common [ ] types of glass under consideration varies from 2.7 to 10.4 X 10-s per degree Centigrade, over the range 20° to 400° C. For reference, the thermal expansion curves of several types of glass used for sealing by the lamp and tube industries are given (Figs. 1 and 2). This paper covers a detailed investigation of the thermal expansion of a series of nickel-iron alloys in which the nickel content varies from 30 to 70 per cent. Particular stress is laid on the alloys that contain between 40 and 55 per cent Ni.

Jan 1, 1938

By Forbes K. Wilson

Dick Hunt is known for having said, "Ore bodies are found but mines are made." This was certainly true of the Ertsberg-it was stumbled upon, literally, by a group of mountain climbers, but to develop it into a mine took 12 years of concerted effort. For more than a century, explorers had attempted to penetrate the jungles of New Guinea and climb the snow-covered Mt. Carstensz, named for a Dutch navigator who first saw it in 1620. But the first to succeed was the Colijn expedition which reached the 5030-m (16,500-ft) pinnacle in December 1936 after starting out from the south coast57 days earlier. Members of that expedition were A. H. Colijn and Jean Jacques Dozy, employees of Shell Oil Co., and Lt. Wissel, a pilot in the Royal Dutch Navy.

Jan 6, 1977

For some years MINING ENGINEERING has published abstracts of the articles appearing in each issue and also of the Transactions papers published in the Quarterly. Beginning this month, a list of key words is being given with each abstract as an aid to indexing the articles for ease in retrieving them when they are needed. The value of a home or office system of indexing and retrieving technical articles is hard to over-estimate. How often is it that a technical problem comes up and someone says: "Oh yes, I've read something about that." Many hours can be expended tracing down that nebulous source. A modest indexing and retrieval system will save those tedious hours, and the person who is able to produce technical documents when they are needed will achieve an enviable status for being on the ball.

Jan 1, 1964

By G. E. Mellor, R. E. Lippoth, T. B. Faddies

The Trixie mine is located in the East Tintic Mining District. Since production began in 1970 over 450 000 tonnes of ore grading 239 grams of silver, 6.9 grams of gold, and 1.2% Cu have been mined from veins in Cambrian Tintic Quartzite. Detailed geologic mapping and extensive sampling are essential for compiling the data base required for efficiently developing and mining known reserves as well as planning exploration and development work. Although the basic techniques used by the geology group at the Trixie were developed many years ago, the reduced activity in underground precious metal mining in the U.S. have made these techniques less familiar to many presently active geologists. The increased activity in precious metals search and exploration again offer cause for the application of these techniques as a prerequisite to efficient exploration, development and production.

Jan 1, 1984

By D. J. Crouse, W. D. Arnold

The potential behavior of radionuclides released in an underground nuclear detonation to fracture copper ore for subsequent in-situ leaching and copper recovery was studied with regard to contamination of the copper product and hazards to operating personnel. The laboratory test results indicate that only small fractions of the radioactive fission products would be dissolved on leaching the ore. Tritium (as tritiated water) would be the dominant radionuclide in the circulating leach liquor, assuming use of a fusion explosive. The test results showed solvent extraction to have important advantages over cementation for recovering copper from the leach liquors. While the radioactivity of the copper metal product produced by either method should be extremely low, the solvent extraction process provides a more effective separation of copper from the radioactive contaminants and entails fewer radiation protection problems. For these reasons it is the preferred process.

Jan 1, 1976

By S. R. B. Cooke, R. O. Huch, C. S. Chang

IN the flotation of iron ores laurylamine derivatives have been used for considerable time.12 To effect satisfactory separation of the gangue, predominantly silica, from the iron oxide minerals, the addition of specific depressants for the iron oxides has been found necessary. Starches and starch products have been used for this purpose. 3 There is, however, very little published information on the effects of these materials and other variables on this process. In some cases it has been found that prior acid scrubbing and desliming are essential, 4 and depending upon the efficiency of the subsequent washing step, there will be accompanying changes in pH. It was the object of this investigation to test and observe the effects of the above factor as well as to examine and compare the action of various starches and starch products.

Jan 12, 1953

By F. Milton Lewis, Roshan B. Bhappu

In Part I of this article, published in the September issue of MINING ENGINEERING, Edward S. Frohling and Robert M. McGeorge of Mountain States Mineral Enterprises, Inc., reviewed the general overall financial aspects and methods of raising the necessary capital for developing the mine. In Part 2 of this two-article series, we will present several case histories to show how realistic feasibility studies are used for evaluating the choices and options entailed in mining ventures. Basically, after a potential ore body has been discovered, and the necessary funds obtained for the development of the deposit, the next major problem is one of ascertaining what specifically is to be produced, and the costs of production. The profit potential of the mining venture can then be accurately assessed by the mine owner, operator, or loan officer.

Jan 10, 1975

By R. J. Charles

SEARCH for a consistent theory to explain the relationship between energy input and size reduction in a comminution process has accumulated, over the years, an enormous amount of plant and laboratory data. Although some correlation of these data has been possible for purposes of engineering design and for the advancement of research in fracture, there is still great need of a means of predicting behaviour of a solid when it is reduced in size by mechanical forces. The best known hypotheses proposed to describe the energy-size reduction relationships in crushing and grinding stem from a common origin. The present article analyzes problems of comminution in the light of the precepts of this origin. Its object is to reconcile points of difference between these well known hypotheses and to present relationships more widely applicable to comminution studies.

Jan 1, 1957

By B. G. Langston, R. D. MacDonald, F. M. Stephens

WITH the development of uranium ores that contain substantial amounts of acid-consuming compounds, the alkaline leach has become an attractive method for extraction. Considerable work has been done on both atmospheric and pressure-leaching with aqueous solutions of sodium carbonate and sodium bicarbonate as the lixiviants.1,2,3 For the treatment of uranium-bearing limestones and other high-lime (CaO) ores, the sodium carbonate leach has proven attractive because it avoids the high reagent consumption incurred by the reaction of sulfuric acid with lime. In addition, the corrosion problems with sodium carbonate are negligible as compared with those encountered in the acid-leach system. The sodium carbonate leach, however, does not yield as high an extraction of the uranium as the acid leach and is not attractive for economic reasons when treating ores that are high in sulfates or sulfides.

Jan 9, 1957

By Donald F. Saunders

Means and relative standard deviations were calculated for eU, eTh, K, and their ratios for aerial gamma-ray spectral data in 29 quadrangles at 1:250,000 scale. Known or suspected uraniferous provinces were characterized by: 1) Higher eU, eTh, and K means (due to generally higher radioelement concentrations); 2) Higher relative standard deviations for eU, eU/eTh, and eU/K (reflecting the presence of local uranium enrichments); and lower mean eU/eTh and eU/K values (showing uranium loss from "average" rocks to form local enrichments). "Uranium favorability indexes," i.e., combinations of the sensitive variables, show an excellent qualitative relationship to known occurences and geologic favorability. Results appear to confirm the existence of long-term crustal uranium provinces formed at the time of emplacement of the oldest known rocks.

Jan 1, 1980

Capable of processing 3500 tpd of uranium ore, the United Nuclear-Homestake Partners' mill in Grants, N. M., differs considerably from the nearby mills of Anaconda and Kerr-McGee in at least two major aspects: it leaches uranium ore with an alkaline solution of Na2C03 and NaHC03 instead of sulfuric acid; and it recovers yellowcake directly by precipitation from the pregnant alkaline leach solution, without any need of ion exchange or solvent extraction circuits. A first look at the flowsheet shows that this mill has two separate grinding and leaching circuits. Reason for the double circuitry: the mill treats, on a toll basis, uranium ores for Anaconda as well as for the partnership, and it must also treat ores coming from mines separately owned by Homestake Mining Corp. and from mines owned by United Nuclear Corp.

Jan 8, 1974

By A. Tobey Yu

Despite its inherent low Btu content, western coal's low sulfur content may provide a near-ideal answer to satisfy US goals for clean air and energy self-sufficiency. Vast reserves, amenable to low-cost strip mining, serve as a powerful economic basis for its viability as a primary and dependable source of energy for the coming decades. A major consideration, the solution of which may not be obvious, is the transportation cost. These deposits are remote from the utilities of the heavily populated eastern regions of the US (Fig. 1). A coal mine in Montana is likely to be more than 1500 miles from its utility market, while an eastern coal mine may be situated only 200 miles away. Thus, the question raised is: how can the haulage cost of western coal be substantially reduced to an acceptable level?

Jan 7, 1975

By Brij M. Moudgil

Disposal of fine coal refuse is one of the major technical problems which could adversely affect growth and development of the coal industry. At present one of the most: common methods for disposal of fine coal refuse slurry involves impounding the slurry behind dams. However meeting new federal and state government regulations for building, maintaining and reclaiming these impoundments in addition to terrain and space considerations render this technique to be only marginally competitive with other disposal methods. The coal industry has been actively engaged in developing alternate disposal techniques which are economically feasible and environmentally acceptable. A review of coal refuse disposal problem and current refuse disposal practice both in the eastern and western coal fields is presented. Various promising techniques being developed for economical and safe disposal of fine coal refuse slurry are also discussed.

Jan 1, 1980

By Raymond A. Bradbury

The first diesel-powered Scooptram has now been in service for 21/2 yr at the I-C mine of Martin County Coal Corp. It has become the workhorse of the operation, being used around the clock many days. The fleet of nine 20-ton capacity Teletrams used behind three Jeffrey Heliminers now have more than 1 1/2-yr experience in the Coalburg mine. They have been exposed to some difficult conditions which, include steep grades, water, mud, and rutted roadways. These units have proven to he both rugged and powerful. The safety components and shutdown systems make these haulage units very safe for underground coal mines. A clean-burning engine, a satisfactory exhaust conditioning system, and good ventilation are the keys to maintaining a safe and healthful atmosphere for the underground operators and other employees.

Jan 1, 1976

By H. A. Guess

INTRODUCTION. HISTORY AND PRODUCTION STATEMENTS. SOUTHEAST Missouri is the oldest of the large producing districts of the United States. The first recorded production from disseminated ores was in 1869, although for many years prior to that time lead had been mined from shallow pockets, and steady growth in production has been shown ever since, the greatest increases being during the past five years. The production by years for each of the operating companies from 1869 to 1907, inclusive, is given in Table I. In Table II. is given the production by years from 1908 to 1912, inclusive, for the district as a whole, showing the tonnage of crude ore mined, yield in concentrates, average assay of concentrates; yield in metallic lead both per ton of crude ore and in total; also approximate value of the yearly production.

Jan 12, 1913