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Papers published by the Institute are issued in a variety of forms MINING TECHNOLOGY, issued every other month, contains the TECHNICAL PUBLICATIONS on Metal Mining, Minerals Beneficiation (milling and concentration), Industrial Minerals (nonmetallic) and Mining Geology, Mining Administration, and Geophysics papers relating to Metal Mining (A, B, H, I, K, L ) METALS TECHNOLOGY, issued eight times a year, contains the TECHNICAL PUBLICATIONS of the Iron and Steel Division and the Institute of Metals Division, and once or twice during the year those on Non-ferrous Metallurgy (reduction and refining of nonferrous metals) (C, E, and D ) PETROLEUM TECHNOLOGY, issued every other month, contains the TECHNICAL PUBLICATIONS of the Petroleum Division, together with Geophysics papers relating to -the finding of Petroleum (G, L ) COAL TECHNOLOGY, issued four times a year, contains the TECHNICAL PUBLICATIONS of the Coal Division (F ) MINERAL INDUSTRY EDUCATION DIVISION papers appear in a TECHNOLOGY according to classification of subject matter DISCUSSIONS appear in the respective TECHNOLOGY as available MINING AND METALLURGY is the monthly magazine, which contains papers of general interest and news of the membership

Jan 1, 1952

By Kingman, Robert I.

SUFFICIENT testing has been .performed with the Dutch State Mines Cyclone for thickening and desliming flotation feed at the concentrator of the National Lead Co., Tahawus, N. Y., to prove its application for this work. It is the purpose of this article to present some of the test results, operational details and advantages of cyclone thickening and classification. The metallurgy of the mill operation was described by Frank R. Milliken, assistant manager of the titanium division.

Jan 1, 1950

By Alan M., Bateman

MR. JORALEMON'S dispassionate discussion of this subject in TECHNICAL PUBLICATION 340 of the Institute shows clearly some of the failures and successes of geology in the discovery of ore deposits. He forces us to recognize, with humility, that chance has played a greater part than geology in the recent discovery of several great copper deposits. I think, however, he wrongly ascribes to unexpected or chance discovery some deposits that were found as a direct result of geological investigation. I refer to the Rhodesian copper deposits,, particularly Roan Antelope and Mufulira, both mentioned by him as having been found by chance. Also,. I think Mr. Joralemon's paper, inadvertently, does not- give the proper credit for the early recognition of the possibilities of these deposits. I feel sure that Mr. Joralemon and the gentlemen given credit by him will welcome any further information on this subject that will throw light on what will some day- be of. historical interest and importance. Consequently, I should like to set forth some additional data that throw light on who should receive the most credit, and' to indicate that, in my opinion, sound. geological reasoning and not chance is to be, credited for the development of the. Roan Antelope and Muf ulira mines.

Jan 1, 1931

By Albert E. Greene

Processes for the removal of phosphorus from iron or steel are steadily assuming greater importance in view of the abundance of high-phosphorus iron-ore and the diminishing supply of pure ore. In the present methods of removing phosphorus by the basic open-hearth or basic Bessemer process, or even by electric processes, complete control over the metallurgical conditions is either impossible or has not yet been realized. The removal of phosphorus has so long been accomplished along certain well-defined lines, that when the electric furnace made its appearance metallurgists adhered to the same old reactions used in the older processes and failed to appreciate and take advantage of the new forces at their disposal. One object of the present paper is to set forth more clearly the metallurgical reactions by which phosphorus can be removed from iron, and to show the necessity of controlling the conditions, and particularly the temperature, by means other than combustion in the furnace-chamber. Invariably, the commercial removal of phosphorus has been accomplished by oxidation. The reactions involved in oxidation of phosphorus in general consist, first, of the formation of P2O5 and second, the combination of this oxide with lime, forming calcium phosphate, which latter is held in a slag high in iron oxide. In the present-used processes, the phosphorus is never removed without the assistance or presence of considerable quantities of iron oxide. The oxygen for removal of phosphorus in the basic open-hearth process comes largely through the medium of iron oxide and furnace-gases, but not

Jan 1, 1913

By W. J. Schuster

*Original Pages Missing From Book HANNA COAL CO., Division of Pittsburgh Consolidation Coal Co., operates three large under- ground mines in eastern Ohio. The section of Pitts- burgh No. 8 coal seam in which these mines are located varies in thickness from 52 to 64 in. It is immediately overlain by a stratum of shaly material 12 to 15 in. thick locally known as draw slate, which is structurally very weak and which disintegrates rapidly upon exposure to atmosphere. Immediately above the draw slate as it is normally found is a band of extremely high ash material 6 to 12 in. thick known as roof coal or rooster coal, and above this is a stratum of conglomerate material varying from 4 to 10 ft in depth. Overlying the conglomerate is' a relatively thick stratum of limestone, the first stable material above the Pittsburgh coal seam in eastern Ohio. With the method of full-seam mining that has been adopted, draw slate is shot down, loaded with the coal, and removed in the preparation plants. The roof coal then becomes the permanent roof. The major problem in mining the No. 8 seam in eastern Ohio is control of the roof. Since the strata above the draw slate contains no material with a structure firm enough to provide self-support, the roof begins to sag in a relatively short time after the coal and draw slate have been removed. The problem thus becomes one of getting temporary safety posts under this roof as quickly as possible to prevent a break or separation from occurring either in the roof coal or in the conglomerate above it.

Jan 5, 1954

By P. St. J. Perrott

AN explosive of balanced composition might be expected, on first consideration, to develop maximum propulsive strength.1 This hypoth¬esis is based on the assumption that an excess of oxygen would act simply as an inert material with a consequent lowering of flame temperature, also that a deficiency of oxygen would tend toward incomplete reaction of the combustible materials, thereby preventing development of the full strength of the explosion. Actually, however, it can be shown both theoretically and experimentally that an explosive having a certain oxygen deficiency will develop the greatest propulsive strength. This fact has been known to the technical staffs of explosives manufacturers for many years, but it has not always been recognized by explosives engineers in the field. For example: There is a fairly widespread opinion that the wrapper of a stick of dynamite is merely a container for the explosive and that it plays little if any part in the development of propulsive strength. Actually, it can be shown that the wrapper enters fairly completely into the explosive reaction. In the case of most gelatin dynamites, a given weight of explosive from which the wrappers have been removed will develop considerably less strength than the same weight of explosive plus wrapper, in spite of the fact that the latter combination contains less weight of the actual explosive ingredient. It can also be shown that a cartridge 7/8 in. in diameter may be stronger, weight for

Jan 1, 1928

By R. R. Klimpel Discussion by C. C. Harris, L. G. Austin

C. C. Harris (Columbia University) — The authors ' have presented relationships for the random division of a magnitude into r + l parts taking account of the order of selection. Interpreting their model in comminution terms, their Eqs. 7, 9 and 11 refer to the one-dimensional case; that is, to the subdivision of a long thin rod at random. It is assumed that the fragments may be indefinitely small. Real materials, however, are limited in the degree of subdivision which can be attained through the intervention of practical restrictions. One in fine grinding is the depletion of microflaws as material becomes finer. Another is the

Jan 1, 1969

By C. F. Cornell, Henderson, A. F. Dunyon, D. A. Dahlstrom

IN processing magnetic taconites several steps of crushing, grinding, classification, and magnetic separation are required to produce a 60+ pct Fe concentrate. Usually the final concentrate is in a slurry form of 55 to 70 pct solids by weight and is further characterized by a particle size of 60+ pct -325 mesh. In taconite plants already completed or under construction the conventional method used to obtain pellets suitable for blast furnaces is to filter the concentrate slurry, ball the filter cake, and then harden the green pellets in a traveling grate or in a vertical shaft furnace. Large tonnages must be handled in minimum floor space, with reduced maintenance and lowest possible operating cost. Filtration must therefore achieve two objectives: 1) high filtration rate-in terms of pounds of dry solids per hour per square foot of filtration area-at a low filtrate solids concentration, and 2) a filter cake moisture that will always permit efficient balling within the normal fluctuations of plant operating conditions. If moisture contents are too high, balling may be impossible or result in a mushy ball without enough green strength for the firing operation.

Jan 3, 1957

Diffusion in Solid Metals. BY ROBERT F MEHL (Institute of Metals Division Lecture Tech Pub 726 in Metals Tech, Aug , also Trans, vol 122 22,500 words ) Diffusion in solid metals constitutes one of the important fundamental phenomena in metallurgical behavior Apart from its obvious importance in processes such as chromizing, carburizing, nitriding and calorizing, it plays an important part in the processes of homogenization, age-hardening, and transformations in steel, its scientific importance is no less great Diffusion may occur within a grain, along a grain boundary, or upon a surface, though the exact and even the relative values of these separate processes are known for only a very few cases The requirement of solid solution formation presents the possibility of identifying solid solution phases by a study of diffusion layers Some distortion accompanies diffusion, leading to little¬ understood grain-size changes Distortion assists diffusion though usually it dis¬appears before diffusion has become extensive In a binary system the rate of diffusion is the more rapid in the lower melting metal Many of the published data are too qualitative to permit sound scientific conclusions Age-hardening data may be treated as diffusion data and rates of reaction in steel could profitably be studied from this point of view Studies on diffusion are of great importance to the develop-

Jan 1, 1937

Henry Carlisle: This is June, 1961, and my friend Arthur Bunker is on the other side of the tape recorder. I, Henry Carlisle, am pursuing the hobby of chronicling the interesting parts of the mining careers and the lives of well-known mining engineers. Now, Arthur, supposing we skip, for the time being, where you were born and brought up, and start right in with where you went to school. Arthur Bunker: I graduated from Taft School and then went to Yale, Sheffield Scientific School, and took a course in electrical engineering. I was quite fascinated by higher mathematics and physics, and this offered more in mathematics and physics than any other one of the engineering courses at that time. The school was only a three-year course, and so I graduated from there in 1916.

Jan 8, 1963

Jan 1, 1964

By Tadeusz Cyrul

Results of a large scale compression test in situ are the subject of discussion. A cube of coal having an edge length of 1.5 meters was subjected to uniaxial compression tests in situ. At the same time both load and deformation were controlled. Deformations were measured on 60 short measurement bases, each 23 cm in length. The bases were uniformly distributed on the side surface of the cube, forming five horizontal rows and twelve columns on the development of the surface. Readings were taken from each gauge for each level of loading which was increased step by step. Due to heterogeneity of the rock, readings showed scatter. Scattered data were approximated by a plane, using the least squares method for each row separately and for the entire population of bases. Orientation of the planes are analyzed. The geometrical measure of the bending moment is introduced. It shows that the magnitude of the bending moment and the bending plane differed from row to row, thus implying that the cube was not only bent but twisted as well. This complex behaviour of the coal cube is apparently caused by its heterogeneity and vertical anisotropy. The results constitute a contribution to the verification of existing design criteria on the stability of mining pillars.

Jan 1, 1984

By E. F. Koch, J. L. Walter

In a study of the structure and properties of tungsten wire used for lamp filaments, it became desirable to perform transmission electron microscopy on the wire in the annealed as well as in the drawn condition. Wire used for lamp filaments is generally drawn to diameters less than 0.010 in. which is too fine for the preparation of transmission samples from single wires. Thus, it is clear that some assembly of wires must be used to form a "wire sheet" similar to that used by Glenn and Duff.' Also, because recrystallized tungsten wire is brittle at room temperature, the "wire sheetJ' must be rigidly contained during any subsequent grinding and polishing operation. With these conditions in mind, a technique was devised for thinning tungsten wire of 0.001 to 0.010 in. diam for transmission electron microscopv. Sample Preparation. The commercially doped (218) tungsten filament wire was obtained from the Lamp

Jan 1, 1969

By M. R. Geer, H. F. Yancey

THE performance of coal-washing equipment, that is, the effectiveness with which coal and impurity are separated, is a subject of undisputed interest to all concerned with the preparation of coal. Through the years much has been written in both American and European literature on the performance of coal-washing equipment and its interpretation, but until recently no effort has been made to consolidate this wealth of information into a single, comprehensive treatment of the subject. A splendid effort in this direction was made at the First International Conference on Coal Preparation held in Paris in June 1950 in which representatives from virtually every coal-producing country participated. Although the scope of the conference covered the entire field of coal preparation, many of the sixty-odd papers and a great deal of the discussion dealt with the subject of evaluating washery performance. Prominence was given this subject by the Centre d'Etudes et Re-cherches, des Charbonnages de France, which sponsored the conference. This research organization, generally referred to as Cerchar, was formed in 1948 following the nationalization of the French coal industry. Since that date it has conducted an intensive study of coal preparation. Perhaps because of a fresh viewpoint, Cerchar realized immediately that complete information on the performance of French washeries and a thorough understanding of the mechanism of gravity separation were the fundamental prerequisites in a program to improve preparation practice. For this reason Cerchar concentrated on obtaining performance data and on a comprehensive study of methods of evaluating such information. Some idea of the magnitude of this work will be appreciated from the fact that 175 performance tests were made in 44 plants. The work performed by Cerchar emphasized a condition that is recognized by many of those concerned with coal preparation, namely that the lack of uniformity in presenting data on washery performance, the diversity of methods used in evaluating such information, and the frequent confusion of the terms related to performance have been prime factors militating against the progress from art to science. Thus, Cerchar feels that standardization of the methods employed for evaluating washery performance, not only in France but in the entire world, is essential to progress, and the prime objective of the Paris conference was to seek international standardization of the evaluation methods advocated by Cerchar. At the conclusion of the conference the question of standardization was referred to the International Standards Organization. A careful study of the dozen papers on the subject of evaluating washery performance presented at the conference reveals that none of the methods is new; most of them date back over a decade. Nevertheless, the intensive scrutiny of these methods brought about by the conference unquestionably has resulted in a valuable exchange of ideas and a clarification of thought that could scarcely be achieved in any other way. The object of the present report is to make available to the American coal industry the ideas developed at the conference which seem most important from an American viewpoint and to provide a critical analysis of some of the evaluation methods advocated by Cerchar. The various methods of evaluating washery performance are illustrated partly with data that have been published in American literature, and some new data have been obtained as the result of experimental work undertaken since the conference to provide information on certain controversial points. An English translation of the proceedings of the conference, including the discussion as well as the papers, will be available,' and previous to the conference Coal Age2 published a very brief description of some of the principal evaluation methods used by Cerchar. Americans will appreciate as well as do the French the desirability of standardizing both the termi-

Jan 1, 1952

By Forrest K. Pence

BENTONITE deposits are known to occur in Texas within the Jackson group of formations. This group represents the uppermost Eocene age sediments found in the coastal plain area of Texas. It outcrops across this area of the state in a narrow band of some 4 to 20 miles width. The outcrop pattern roughly parallels the present Gulf of Mexico shore line and is some 100 miles inland from the Texas shore, Fig 1. The principal bentonite deposits are found in the areas where this outcrop pattern cuts across the south-central Texas counties of Karnes, Gonzales, and Fayette. In these deposits, the better quality bentonite is found in the lower or bottom layers of the volcanic ash deposits in which they occur. Some of these better quality bentonites develop very light colors upon firing and therefore justify their being classified as "white firing." The deposits in Karnes and Gonzales Counties apparently occur in commercial quantity, whereas the white firing strata so far uncovered in Fayette County have been too thin to be classified as yet as "commercial." A study of the ceramic properties of the weathered ash in Gonzales and Karnes Counties was reported in 1941.1

Jan 1, 1949

By John F. Walker

WITH an estimated production of over 936,000,000 for the first six months, the gross value of mine production for 1937 in British Columbia should exceed $70,- 000,000. This figure, if attained, will establish an all-time record for the Province. Great changes have taken place in the different divisions of the mining industry since 1929, the previous peak year of mineral production. A brief review of the earlier history of mining in the Province will also be given.

Jan 1, 1937

By Allen D. Gorrison

EFFORT to develop fundamental quantitative information and improved technique in the production of petroleum has long been faced with difficulties of a particularly evasive nature, owing to a combination of circumstances. In the first place, petroleum comes from far below the ground, out of sight, so that information derived from indirect observations must be extrapolated to reservoir conditions. If one does not force the analogy too far, the petroleum engineer may be said to be somewhat in the position of the astronomer. The actual phenomena which he wishes to observe in detail appear at a place so deep in the earth?s crust that personal observations and direct experiments are impossible.

Jan 1, 1942

Jan 1, 1939

By I. E. Rosenzweig

The problem considered in this paper is as follows: An arbitrary horizontally stratified area is given. The electrical properties of this area are characterized by a function p(z) (Fig. I), which shows the relationship between resistivity p of the soil and the depth z. For such general case the apparent resistivity p* will be computed, by earth-resistivity measurements carried out by any given configuration of electrodes. General solutions of this problem appear to be very important for interpretation of field results of resistivity measurements, concerning structural investigations. Such solutions have been given by many authors for the special case of a finite number of homogeneous layers (Fig. 2)lV4 as well as for the more general case of continuously ranging resistivities.5-8

Jan 1, 1940

By Raymond E. Funderburk

Today, there are four alternatives available for disposal of highly toxic, non-radioactive hazardous waste: deep well injection, chemical processing, landfill and incineration. However, based upon research conducted by the author, a fifth alternative now exists. Disposal in salt. Salt, because of its chemical characteristics, is an ideal medium for retention of inorganic hazardous waste. Except for a few elemental compounds such as lithium and potassium, there is no reaction with sodium chloride. In the family of inorganic wastes, there are basically seven suites of waste that may be mixed together without any chemical reaction. The process developed by the author would be to take a suite of waste, either dewater or add moisture, add a solidification agent to the mix and slurry pipeline the mass into a cavern. Residence time before hardening can be adjusted, but the nominal time until full solidification is 48 hours. Once solidified, the mass will reach compressive strengths exceeding 3000 psi. The slurry can be introduced into an evacuated cavern pumped free of brine, or it can be placed beneath the brine and the waste will force the brine to the surface. The latter technique requires a high degree of engineering control to prevent contamination of the brine leaving the cavern-thus creating more hazardous waste and additional problems. The Environmental Protection Agency endorses the concept both at the research level and within EPA Headquarters. The technology will soon be utilized in a salt formation in Texas.

Jan 1, 1985