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By David M. Parkes, Junie Lindsay

A review of the movement of coal in water is undertaken from a practical rather than a theoretical view point. Installations are described in which coal is transported on gradients down to 2.5' and others which move coal at a water-coal ratio of 1:l by weight. The water cycle of the hydraulic mining system is discussed. In many applications this can be a closed circuit. The coal dewatering system is illustrated, making particular reference to the problems of storage of coal-water mixtures between the mine and the plant. Water treatment is done in thickeners down to 100 ppm which is normally sufficient for re-circulating through high pressure pumps and monitors.

Jan 1, 1978

By J. H. Berryman

THE use of oxygen as a bath reagent in hearth furnaces during the refining period is a familiar story. Investigations and tests in which oxygen was substituted for iron ore to reduce carbon date back 25 years and include the work of Bigge,1 Browne,2 and Chelius.3 During this past year the majority of the experimental work in the use of oxygen was carried on mainly in open-hearth shops, since it was felt that the greater field for application lay in this type of furnace. Much constructive work was done in evaluating the carbon-oxygen relationships, as reported by Slottman and Lounsberry4 and by Hughes.5 Steelmakers using the electric furnace have been actively engaged meanwhile in an experimental program of their own, with such success that the oxygen injection pipe has become a tool in the day to day production of low-carbon and stainless steels.

Jan 1, 1947

By Frank C. Schader

JOHN CARTER ANDERSON, Kingman, Ariz. (communication to the Secretary *).-From an extended study of the Oatman and Secret Pass districts of Mohave County, Arizona, I believe that the genesis of the ore deposits, in most cases, is directly connected with rhyolitic intrusions later than the Tertiary flows; and that the developments of, the future will prove these intrusives to be the primary source of the ore. In support of this opinion I will instance the Wilhelm-Eclipse dike in Secret Pass and the Murdock, Nellie, Black Range dike and ledge in the southern part of the Oatman district. The Wilhelm-Eclipse dike is a very fine-grained light-colored siliceous rhyolite dike with a strike of N.45W. traversing the full length of the Secret Pass district about midway between two major faults which mark the easterly and westerly boundaries of the district. These faults .have lifted the block between so that erosion has exposed the pre-Cam-

Jan 4, 1917

By N. O. Johnson, J. Boyer, D. H. Sargent, R. B. Frahme

Although the Western bentonite industry has grown rapidly, it is facing major challenges to sustained growth. The fundamental penalty of costly overland transportation to both domestic markets and to US seaports is of increasing importance; as both substitute materials and foreign bentonites present more formidable competition in the historic market areas of drilling muds, foundry sands, and iron ore pelletizing; and as foreign demand grows more rapidly than domestic demand. The Western bentonite industry is facing these challenges by altering its transportation patterns, by upgrading of products, and by emphasizing customer service and stringent quality control.

Jan 9, 1979

By W. R. Ingalls

SOME months ago, I had occasion to make an investigation that introduced the subject of blue powder that is produced as a byproduct in zinc dis-tillation. Although every zinc smelter is aware that more or less blue powder production is inevitable and there is a common practice as regards the treatment of it, the specific and quantitative data respecting the subject were more imperfect than would have been expected. I had reports from eight important works. Some of the data were especially determined for my investigation. Speaking generally, there is a good deal of uniformity in the figures, all of which show that the blue powder product, bears a large proportion to the ore originally charged into the retorts; that a large proportion of the retort capacity is devoted to the redistillation of blue powder; and that of the spelter product of a furnace about 30 per cent. is derived from blue powder, i.e., it is zinc that has been distilled twice. The figures from the works are given in the following table:

Jan 4, 1922

By William B. Plank

Mineral engineering student enrollment in U. S. and Canadian schools for 1955-1956 is 11,408, an increase of 11 pct more than last year. The undergraduate and graduate engineering students in both countries number 251,765, or 13 pct more than last year. These figures have been released by the American Society for Engineering Education. The largest increase in the undergraduate mineral engineering group in the U. S. is in ceramic engineering, with 676 students, or 31 pct more than last year. The next largest increase is in mining which shows a gain of 13.5 pct, compared with a gain of 13.1 pct in the total undergraduate enrollment in all engineering schools approved by the Engineers' Council for Professional Development. This figure is 190,355, which approaches the prewar figure. Metallurgical undergraduates increased 13 pct; geological, 5 pct; and petroleum, 2.5 pct. This year the figures for geophysics are combined with those for geological engineering, making a total of 1610 undergraduates, of which the geophysicists comprise about one seventh.

Apr 1, 1956

By John M. Cigan

Samples of copper-lead concentrates from the mine of Cia Minerals Santander, Inc., a Peruvian subsidiary of the St. Joseph Lead Co. were recently subjected to special analysis. This concentrate was known to contain bismuth which, under some circumstances, might have incurred a smelter penalty. In this case, customers for the concentrate accepted it and requested a higher concentration of bismuth. Although chemical analysis would disclose the presence of the metal, it was not possible with equipment available at the mill in Peru to determine the mode of occurrence in the fine grained ores.

Jan 11, 1964

By W. C. Kerr

When Agassiz and his party of geologists commenced their exploration of the interior of Brazil and the Amazon region, one of the first and, to the last, one of the most novel and striking phenomena which met them everywhere was the great depth of decomposed or partially decayed rock in situ, which mantles, and for the most part conceals, the underlying strata. The same facts strike all geological observers from the North who happen to penetrate the middle and southern latitudes of the Atlantic States. In North Carolina, e. g., the entire middle and western regions, outside of the Quaternary clays, sands, and gravels of the East,—that is, all that portion of the State occupied by the Archæan and Mesozoic rocks,—show everywhere this peculiarity, so new to those accustomed to glaciated surfaces. Not only do the hills and slopes, the mountain chains and

Jan 1, 1880

By Herbert C. Hoover

While the importance of the superficial alteration of golddeposits is recognized in pure science, it seems often to be singularly disregarded among engineers in practice. Its great practical bearing lies in the exploitation of new regions; and nowhere are the disastrous results of ignoring it more vividly shown than in Western Australia, where the impoverishment of the ores, and their frequent transition from free-milling' to refractory character in depth (things, as a rule, neither anticipated nor ascertained by exploration beforehand), have brought many companies to ruin, or caused the loss of much money squandered on machinery adapted only to temporary conditions.

Jan 1, 1899

By Alexander Sutulov

The Western industrial nations are facing today what can be defined as a gradual takeover of their investments in the developing world and more importantly, they are beginning to feel approaching problems with their adequate raw materials supply. This puts them into a strategically hazardous situation, which years ago would probably have been solved by conventional wars. However, the present political and military situation, and particularly the development of nuclear arms, makes such confrontations almost impossible or at least extremely dangerous. Thus other peaceful and more pragmatic solutions should be sought. This is particularly important because the present supply-demand situation in raw materials has a very strong political and ideological background. In the ultimate analysis there are two economic systems, that of free enterprise and the other of the collective or socialistic ownership. Both are competing for world domination, and it seems that both are eager to prove their advantages to the yet uncommitted Third World, which commands the great majority of the human race and a large part of its natural resources.

Jan 7, 1974

By F. G. Loper

Simulation as a mathematical technique is not new. However, recent increases in digital computer speeds and the ease of programming with languages such as Fortran have centered a good deal of attention around simulation in the last few years. By ignoring all but the relevant characteristics of a process, a mathematical simulator may be constructed which, when fed operating data, should react as the process would. The output becomes numbers, instead of tons, however. Thus, a trial-and-error operation of such a simulator will permit management to study a major system change at little cost.

Jan 1, 1967

By D. C. Shelton, C. S. Ek

Corneille S. Ek (Assistant Professor in Ore Dressing, University of Liege, Liege, Belgium) — This is a very valuable paper, in that it shows how it is possible to take care of a multitude of laboratory routine tests, and derive from them successful modifications of flowsheets or of operating methods. The author and the Company appear to be test-minded and this is best seen through the case histories described. There are however some corrections to be made, and questions arise when one studies the paper. If all the equations are to be homogenous, one obviously has to write Eq. 4 On the other hand, it is difficult to accept the definition put on Eq. 7, for that equation, which represents the factor of transformation from tpd of solids to cu ft per min of pulp in Eq. 6, has nothing to do with conditioning. It is evidently assumed here that conditioning means, as Gaudin calls it,' modulation of collection. One would prefer, for Eq. 7, the appel-ation "pulp conversion factor". Eq. 8 and 9, giving the amount of reagent to be fed

Jan 1, 1965

By Charles F. King

The only investigations on record of the reactions occurring (luring the Bessemer blow are of charges containing a large percentage of manganese, with the exception of' two partial analyses by Snelus and Barker of the English method, where a low percentage of manganese was used. They do not give the analysis of the spiegel, [lor do they report any graphitic carbon after the first stage of the process. Both report only traces of manganese after the first stage until the addition of spiegel. The slags corresponding to the samples of metal were not analyzed.

Jan 1, 1881

By Charles F. Brush

The compression of gases to a very high degree, for purposes of scientific research, has long presented serious difficulties to the physicist. Great advances have been made of late years in the construction of ordinary air or exhaust pumps, while very little has been done towards the improvement of compression pumps. The principal difficulties encountered in the construction of such apparatus are the existence of the so-called "dead space" in the pump barrels, leakage of the piston packings under high pressure, and the trouble arising from the unequal expansion of parts caused by the development of the latent heat of the gas during compression. Of these obstacles to success, the "dead space" is far the most serious, as it fixes a limit to the performance of the pump beyond which it is impossible to carry the compression. The writer having occasion, some time since, to make a series of investigations on gases very highly compressed, and finding no apparatus, or description of apparatus, adequate to produce the required

By David A. Summers, Steven McGroarty

The last ten years has witnessed the change in water jet cutting studies, on rock, from laboratory testing to prototype use of field equipment. Unfortunately, while equipment and technological developments have occurred, the understanding of the exact mechanisms of water jet erosion have been less well developed. Commonly, theoretical evaluations have used the uniaxial compressive strength of the target rock as the major parameter of rock erosion resistance . It is considered that the structural properties of the rock, and most particularly, the flaw density and heterogeneity of the rock are much more important parameters. This is demonstrated and discussed. Locating the jet and target under water and pressurizing the containing vessel makes it is possible to induce cavitation in and around the water jet and create a much slower erosion process.

Jan 1, 1982

By Gerald C. Mathis

FERGUS County, Mont., shown in Fig. 1, is known for its once famous gold mines near the old towns of Gilt Edge, Maiden, and Kendall. But at Heath, a small farming community near the foot-hills of the Snowy Mountains, thousands of tons of gypsum have been mined since 1916. The value of the gold taken from the mines of Fergus County runs into millions of dollars; the value of the products made from the gypsum of the Heath mine is also in the millions. The gypsum mine will continue to produce for many years, while the gold mines are closed today.

Jan 2, 1953

By W. E. C. Eustis

In September last I had my attention called by Mr. R. G. Leckie to a deposit of nickel in the township of Orford, province of Quebec. In many ways it has proved to be a subject of great interest. As this ore is, as far as I can learn, entirely new in mineralogy and metallurgy, it has seemed to me that it would be a matter of interest to the Institute to have laid before it, in a short paper, the peculiarities I have met with in studying it. This deposit of nickel was first described by Dr. T. Sterry Hunt, our President, in the Geology of Canada, 1863, p. 738, in the follow ing terms: " The general diffusion of nickel throughout the magnesian rocks of the Quebec group has been already noticed. It has, however, never been met with in any considerable quantities in these rocks, although workable deposits of its ores may reasonably be looked for

Jan 1, 1879

By C. G. Dunn

THE present note, which was given in the form of a Research in Progress item,' traces the origin of secondary recrystallization grains produced on annealing a cold rolled bicrystal specimen. The investigation began with the realization that a recently acquired conception for the origin of secondary grains produced on annealing cold rolled single-crystal specimens might require modifications for the case of polycrystalline materials. The stated conception2,3 begins with several conditions to be met by primary recrystallization: 1—a primary re-crystallization structure to consist of many small primaries and relatively few large primaries (diam- eters two or three times the average); 2—a primary recrystallization texture to consist of one strong preferred orientation or component and one or more weak components; and 3—a primary recrystalliza-tion structure-texture combination with some of the large primaries belonging to the weak components of the texture. When these conditions occur, some of the large primaries from the weak components of the texture

Jan 1, 1955

By Edward A. Loria

A SERIES of papers on the study of austenite grain A size in cast steels has been published recently.'" These studies show that in the as-cast state, the austenite grains are quite large, for they form as the steel freezes at a very high temperature, but a simple reheating above the critical range produces a new set of austenite grains which, in many instances, is finer than ASTM grain sire No. 8. Furthermore, there is no apparent relationship between as-cast austenite grain size and subsequent grain size produced by heat treatment. The as-cast austenite grain size can be determined easily in plain carbon and low alloy steels which produce a continuous grain boundary f errite envelope in the as-cast structure. In the case of cast steels whose alloy content produces greater hardenability and suppresses the proeutectoid ferrite transforma-

Jan 1, 1952

By D. R. Franklin, L. L. Lien, C. W. Hoffman

The initial operation of a mining facility is a unique and often underplanned phase of the Project development process. The subject of this presentation is a detailed strategy to effectively and efficiently bring a mining facility to design production capacity. This plan has been applied successfully on projects. It addresses developing the initial operation organization, management of information and problem, putting an appropriate management system in place, developing operations and maintenance information, and effectively training personnel.

Jan 1, 1983