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By John V. Beall

It is difficult to understand why they did it. It was a demonstration of total commitment which sent chills of mixed admiration and fear up and down your spine. The scene was the bodega in Section A, 2660 Level on the 12 to 8 shift. The jefe was patiently waiting for the tea leaves to settle in a large metal cup. His attention was distracted by the appearance of a miner who had a problem. The long and short of it was that the miner believed the branch raise he was driving was unsafe and he wanted the jefe to come and see it. After lunch the jefe went around. First cautiously shining his light to peer up the raise from outside the chute, he then scrambled inside and swiftly climbed the cribs to the face. No question, it was hairy; about 4 crib sets were needed to catch up to the face. The unsupported raise was slabbing. It didn't take the jefe more than a few seconds to ascertain this situation and to slide back down. As he came out of the chute, a small avalanche arrived on his heels and provided a sort of exclamation point to his order; "cerrado!" In other words, shut 'er down.

Jan 1, 1970

By E. T. Cox

WHILe engaged, in the year 1856, in determining the oil-bearing properties of some bituminous coals from Western Kentucky, by subjecting them to dry distillation in an iron retort, which held about a pint;, and to the neck of which were attached several bottles, for collecting the carbon oils, and washing and measuring the gas, I observed that there was a very great gain in the weight of coke thus made, over that obtained from the same coal when charred in a platinum crucible, as is usual in the laboratory for making the proximate analysis of coal. It was thought at the time that the increase of coke, by the former mode of treating the coal, was due to the pressure which the retarded gas exerted upon the solid carbon, and the possible fixing of a portion of the carbon from the volatile hydrocarbons. For the purpose of obtaining a more definite idea of the effects of pressure on the coking of coals, a series of experiments were made this spring under my direction, by my assistant, Dr. G. M. Levete. The results are highly instructive and full of interest, since they point out some peculiarities in the nature of bituminous coals which

MELTING in a hearth and in a basket is almost the same thing; charcoal and bellows are used for both. These are made large or small according to the quantity that you wish to melt, and more or less force of the bellows is applied according to the need. The hearth, bowl, or refinery, as the masters call it, is made with bricks and clay like a forge; opposite the middle of the tuyère a round hole is made like a wash- basin, wide at the mouth and narrow at the bottom where there is a hole for emptying it. A little iron plug is put in this so that it may be closed when necessary, or a piece of brick that is cut and pointed. Now, when this has been well covered all over with ashes, and the tuyère has been arranged so that the wind strikes the center, it is first filled with charcoal and baked very well so that the metal may be kept hot once it has been melted. When it has been baked, it is again filled with charcoal, fire is applied, and it is left to inflame gradually by itself. Then put one or

Jan 1, 1942

By Robert F. Shurtz, William J. Verner

Three basic questions must be answered by an engineer performing an economic analysis of a mineral property: (1) How much can the company afford to pay for the property; (2) At what rate should the property be mined; (3) What will be the return on the investment. These questions often defy reasonable analysis, because at the point in time at which they must be answered little may be known about the grade of ore and the reserve tonnage. The purpose of this report is twofold. First, to derive a method of determining purchase price, rate of production and return on investment which is valid under varying conditions of ore grade and tonnage reserve; and, second, to apply this method to the Margay deposit in an attempt to evaluate it as a business enterprise. This is an actual economic analysis of an existing nickel-copper deposit fictitiously named the Margay. It was carried out for a mining corporation and proved to be the determining factor in the subsequent purchase and development of the property. All data referring to costs, quality and quantity of ore, etc., are accurate and truly represented. Prices used are obsolete but the method is not dependent on those variables. Basic assumptions for the analysis are given in Table I, page 71.

Jan 11, 1966

By D. M. Jamieson, M. P. Pearse, E. R. A. Plumstead

In 1948 the shaft sinking record in the Republic of South Africa was held by the Van Dyk Consolidated Mines Ltd. for a ventilation shaft with a footage of 461 ft sunk during the month of August 1941. This record remained for some ten years; but in the ensuing nine years it was broken no less than 13 times. Table I gives shaft sinking records throughout the world for the 21 years, 1940 to 1960. History shows that the wide, deep, timbered rectangular shaft had passed its peak of popularity by 1948, although it still had a great deal to commend it, both from the sinking and operational points of view. In sinking, it is easy to clean manually, and water can be handled by bailing when wet ground has to be negotiated; its shape also lends itself to equipping concurrently with sinking. In operation it provides the most convenient "in line" hoisting arrangement, and if the ventilation requirements so demand, it offers the simplest solution in that it can be divided into upcast and downcast sections. Furthermore, in the case of a multi-level mine, the shaft compartments can be reduced conveniently if the full area of the shaft is not required to serve all levels.

Jan 4, 1963

By C. W. Parmalee

The ideal fuel for burning ceramic wares is the one that, among other characteristics, has little or no sulfur. For that reason wood was long considered the most desirable fuel but its high cost has practically eliminated its use except in regions where it is very abundant or other circumstances warrant its choice. The fuels commonly employed are natural and producer gas, oil, and coal. The last named is undoubtedly the most important, not only in this country but abroad. Occasionally anthracite is used but the larger part is bituminous. The quality of the coal used depends on the kind and the value of the products being manufactured. For some materials, such as common brick, hollow block, etc., the quality of the coal is of less importance than in the manufacture of polychrome terra cotta, pottery, porcelain, etc. It is obvious that in burning clays that contain notable amounts of pyrite, marcasite or gypsum, as is the case with many common clays, the sulfur content of the fuel is of much less importance. The permissible amount of sulfur in the coal used will depend on the kind of product being manufactured. "A good sample1 of coal commonly used in pottery ovens has something like this quantity of sulfur: total sulfur, 1.20 per cent.; sulfur in ash, 0.11 per cent.; volatile sulfur, 1.09 per cent." This is based on English pottery practice. Correspondence with a. number of leading manufacturers in this country has produced the following figures: Sanitary Ware.—(a) 1.0 per cent, maximum, (b) 0.5 per cent. Sewer Pipe.—(a) 1.2 per cent., (b) 1.1 per cent, present run, 3.0 per cent, has been used. Terra Cotta.—(a) 0.5 per cent, basis of contract, 1.0 per cent, approximate. Pottery.—1.0 per cent, contract, 1.5 per cent, probable content. Enameled Brick.—1.3 per cent, maximum, (a) and (6) designate different firms giving figures. Since a pottery kiln for sanitary ware will require about 14 tons of coal for a bum, the quantity of SO2 that will be generated from a 1-per

Jan 1, 1920

For the year ending February, 1926 PRESIDENT J V W REYNDERS, District 0 NEW YORK, N Y PAST PRESIDENTS E P MATHEWSON, District 0 NEW YORK, N Y WILLIAM KELLY, District 5 IRON MOUNTAIN, MICH FIRST VICE-PRESIDENT E DEGOLYER, NEW YORK, N Y TREASURER , CHARLES F RAND, NEW YORK, N Y SECRETARY FREDERICK F SHARPLESS, NEW YORK, N Y

Jan 1, 1923

By Hannu Penttila, Harrison R. Cooper, Olli Mattila

Two approaches to automated operation in metallurgical processes involve the conventional analog control or, more recently, digital control. The expanding use of digital controls applied to process automation is a comparatively new development. Several current technical reports describe digital control systems in concentrator grinding control, 1, 2, flotation, 3 and smelter operations. 4,5 The principle factors influencing trends to digital control are:

Jan 10, 1976

By George Krauss, Morris Cohen

NUMEROUS investigators1-4 have shown that one of the most conspicuous effects of the reverse marten-sitic transformation in Fe-Ni alloys is the stabilization of the austenite which forms on reversal. However, the present authors5 found a virtual absence of stabilization in a recent study of this subject. The purpose of this note is to account for the discrepancy.

Jan 1, 1963

By Robert Glass Cleland

IN gathering material for this book, I have made extensive use of the archives of Phelps Dodge, contemporary news- papers, and a wide range of secondary sources. Two manuscripts-one on the history of Phelps Dodge by Arthur Train, Jr., and John L. Lawler, the other a biography of William E. Dodge by Richard Lowitt-have been of the greatest value. I owe a particular debt to the authors whose names I have just mentioned. I have also gathered important information and obtained revealing points of view from conversations with many people. Personal visits to the company's mines and plants added knowledge and understanding that nothing else was able to supply. I am greatly obligated to the officers of the company, especially to Mr. Louis S. Cates, chairman of the board of directors, Mr. Robert G. Page, president, Mr. George R. Drysdale, vice-president of Phelps Dodge Corporation, and Mr. Walter C. Bennett, president of Phelps Dodge Refining Corporation, for their co-operation and assistance. Mr. Wylie Brown, former president of Phelps Dodge Copper Products Corporation, also supplied valuable data and deeply appreciated hospitality. In my visits to the Phelps Dodge properties, company representatives extended every hospitality and placed at

Jan 1, 1952

By W. P. Rawles

In the foreword by C. K. Leith, Chairman of The Mineral Inquiry, it is pointed out that the ordinary mineral production tables do not show the commercial control, and that some knowledge of the situation is desirable as a background for the consideration of problems involving mineral raw materials. The report consists principally of tables, accompanied by a brief text, giving the production and an analysis of the control, according to nationality, of 18 minerals: aluminum, chromite, copper, iron and steel, lead, manganese ore, mercury, molybdenum, nickel, nitrates, petroleum, potash, silver, sulfur, tin, tungsten, vanadium, and zinc. For the most part, the production figures for 1929 and the latest figures for reserves have been used. When feasible, the control has been shown at the various stages of production; mining, smelting and refining. American capital was dominant in the production of 10 mineral commodities, including six of the most important; British capital, in four instances; while Spanish, German, Chilean or Chinese interests cach led in the control of one. British, French, German, and Dutch capital occupied second place in the control of most of the important minerals. Between two-thirds and three-fourths of the world's mincral production is controlled by British and American capital.

Jan 1, 1934

By F. C. Blake

THE test of the English cupellation furnace should be so supported that the cupeller can change readily the elevation of the test, and at the same time watch the litharge channel. It is also important to raise or lower either side, independently of the other, in me of uneven wear of the side walls or of the breast. If the refined silver is poured from the test, it is much better to control the lowering of the test from the front than to raise the back by screws or a lever. In order to enable the cupeller to manipulate the test with one hand, when the litharge is running, and to pour the refined silver from the test without aid, I have altered the common support to the test, as shown in the accompanying drawing. The common method of supporting the test is by four screws, working in cross-bar nuts beneath the test. The points of the screws set, into the test plate upon which the test rests. These screws are usually worked by pounding or pulling upon the heads, which may be either small pulleys or straight bars, as shown on the back screws in the drawing. The screws are also worked by turning a crank, which is

Jan 1, 1882

By F. C. Blake

THE test of the English Cupellation furnace should be so supported that the cupeller can change readily the elevation of the test, and at the same time watch the litharge channel. It is also important to raise or lower either side, independently of the other, in case of uneven wear of the side walls or of the breast. If the refined silver is poured from the test, it is much better to control the lowering of the test from the front than to raise the back by screws or a lever. In order to. enable the cupeller to manipulate the test with one hand, when the litharge is running, and to pour the refined silver from the test without aid, I have altered the common support to the .test, as shown in the accompanying drawing. The common method of supporting the test is by four screws, working in cross-bar nuts beneath the test. The points of the screws set into the test plate upon which the test rests. These screws are usually worked by pounding or pulling upon the heads, which may be either small pulleys or straight bars, as shown on the back screws in the drawing. The screws are also worked by turning a crank, which is

Jan 1, 1882

By Maximo Monte-Flores

A PERUSAL of the most recent literature on the subject of hydrocarbons reveals that one point seems, to have been neglected by the various theories; that is, the influence of the bed-rock on the accumulation and distribution of oil and gas. This can be seen from the following statement of the principles of the most accepted theories. ANTICLINAL THEORY The anticlinal theory claims that the accumulation of the hydro-carbons in deposits of commercial importance was brought about by the gravity of the hydrocarbons, the oil and gas being forced to the top of the porous stratum by the difference of the specific gravity of the hydro-carbons and the water. The principal factors toward the accumulation were the general stratigraphic condition of the rocks, their texture and porosity, and their water content. This theory advocated the preexistence of structural deformation as the basis of the motion of gravity, thus implying the principle that the forces that have caused the deformation have had no influence on the movement of the hydrocarbons. STRUCTURAL THEORY According to the structural theory, the accumulation is due, chiefly, to the structure of the subsurface rocks and differs from the anticlinal theory, mainly, in not considering that the motion of the liquids have been caused by the force of gravity.

Jan 1, 1920

By Chu-Phay Yap

This is the first of a series of theoretical papers on the iron-carbon system. A simple critical analysis of the ordinary constitution diagram of the iron-carbon system yields valuable information regarding the nature of the equilibria in the liquid and solid states. It is shown, for example, that the solute in the melt is Fe3C, but in solid Fe (austenite) the solute is carbon. The thermodynamic laws of the depression in the freezing point of solid solutions have been developed and discussed. Using the usual method of plotting the logarithm value of the concentration of the solvent (in this case, the ratio of concentrations of the solvent in the liquid and solid phases) against 1/T, curves are obtained. A rigorous thermodynamic analysis of these curves has been shown to yield considerable information regarding the internal equilibria of the system, with which the phase rule does not deal altogether. In this way, it is shown again that the solute in the melt is Fe3C, but in the solid rFe the solute is carbon. Various heats of reaction (fusion and transition) and other thermal data have been derived: and discussed with a view to correlating the conflicting experimental data obtained by different investigators of the system.

Jan 1, 1931

By Robert E. Tally

The ore reserves of the United Verde Copper Co. in 1907 were estimated at 4,500,000 tons, averaging about 7 per cent copper. Seventy-five per cent of this tonnage was confined to the so-called fire stopes and the remainder was virgin ore. The fire area was being operated at a maximum capacity of 150 tons per day, and the other workings furnished the remainder of the ore, approximately 600 tons per day. The mine was developed to a depth of 900 ft. and the lower levels were considered lean and unpromising. The smelter had been built directly over the ore-bodies. Its site was congested, the ground was settling and maintenance costs were excessive. The major needs of the United Verde obviously were 1. Additional ore reserves. 2. A new and modern smeltery. 3. A method for the mining of the fire-stope ores commensurate with the tonnage and values involved. It is the method specified in point, 3 with which this paper is chiefly concerned. Such a method required the removal of the old smelter, and additional ore reserves were essential not only for the maintenance of production but for the investment necessary for the building of a new smelter.

Jan 1, 1932

ARTHUR KNAPP, Ardmore, Pa. (communication to the Secretary*). -The author has failed to consider the point which in my mind is the most convincing in advocating some sort of a bureau for the collection of well logs. I venture to say that 90 per cent. of the logs as taken today are absolutely worthless to any one but the one who has taken the log. This is largely due to the careless use of nomenclature. The author says on page 289, "He must ascertain which of the many factors might account for the dry hole in question and often only careful examination of well logs will convey this information." I believe that even a most careful examination of the average log reveals nothing. I have at hand a book on petroleum, by a well-known author. This book has a number of logs from fields all over the world, from which I shall illustrate. In a well log from Kansas I find "Soft gray shale" and in one from Humble I find "Hard blue shale." As a matter of fact the shale from Humble is softer than the shale from the Kansas well. The difference is that the drillers in Kansas, being used to limestone and

Jan 5, 1917

By David Baker

In a paper presented to the American Institute of Mining Engineers, September, 1904, entitled uImprovements in the Mechanical Charging of the Modern Blast-Furnace,"' I showed the great fault of mechanical charging-devices to be that the materials charged by the dumping of the skip were separated, the coarse materials having high velocity, and the fine, low— thus giving paths of low resistance through the stock in the furnace, which resulted in unequal distribution of the furnace-gases, unequal reduction, slips, scaffolds, irregular cutting of the inwall, "of" iron, and increased fuel-consumption. I showed how this could be prevented by rotary distribution, through which the irregular distribution in one layer charged is compensated by charging the subsequent layers from succeesively varied positions of the charger, and becomes practically eliminated when the angle between two successive positions is a little more or less than an even fraction of a full circle. Of all the devices then on the market, the nearest approach to the ideal arrangement was found in the Brown distributor, a full description of which was given. The one defect pointed out, however, was the difficulty of maintaining so much mechanism on the top of a blast-furnace. Since the presentation of that paper, I have designed a very

Jan 1, 1907

By John V. Beall

One Sunday night last month the phone rang and it was George Schenck from Penn State. How would we like to see a big scrap operation, he wanted to know. A few days later we were on the Connecticut turnpike headed for New Haven to visit a large scrap operation, M. Schiavone and Sons. George had a large clam basket in the back which he explained was for collecting trophies. The car shredder, he said, turns out some fancy metal shapes. In fact, they have gained a certain acceptance as objets d’art among George's friends and relatives. He thinks there may be a small, but possibly lucrative secondary market for shredded cars in the art world if the idea is imaginatively promoted. On the way to New Haven we received a briefing on the scrap industry. The scrap business grew from humble beginnings. Mostly it was started by a few immigrant Jews who collected junk in hand- or horse-drawn carts. The fortunate one might even have had a truck. Before proceeding further, we hasten to point out that the word "junk" is strictly taboo among scrap people, who prefer to refer to their industry as the "secondary metals industry."

Jan 1, 1970

By Jose J. Alvarez

INTRODUCTION Three major plant processes control the operation of an uranium in-situ mining plant. The three pro- cesses can be categorized under the headings termed - loading, elution, and precipitation. All other plant processes can be subcategorized under the three. In summary, the major plant processes in an in- situ mining plant are: 1. Loading - The pregnant lixiviant from the production wells flows through anion exchange resin. The loading of the uranium on the resin is controlled by various factors, such as ionic strength, valence, functional groups, etc. 2. Elution - The uranium-loaded resin is eluted or regenerated by a high ionic strength solution. The effluent from this process is de- fined as the pregnant eluate. 3 . Precipitation - The pregnant eluate is chemically treated to attain the ideal conditions for the selective precipitation of uranium. Hydrogen peroxide is an ideal precipitating agent under URI conditions. This paper will focus on two of the major processes: Elution and Precipitation. For the most part this relatively young industry has grasped the theory of liquids in continuous flow for the operation of the plant processes. Likewise, URI initially operated the two processes of interest with the continuous flow concept. Through laboratory experiments, URI has abandoned the flow concept and operates the eluting and precipitating stages with the concept of "batch" processes, whereby only one container, filled to a specified liquid level, is chemically processed. In the proceeding sections, each of the two pro- cesses will be discussed in detail, from their original concept to the present operation. Only minor modifications were made to the existing circuits for the conversion with results revealing a greater level of efficiency. ELUTION The elution of the loaded anion exchange resin can be achieved by different high ionic strength solutions. The selection of constituents is dependent on both chemical and economic considerations (i .e., efficiency and operating/restoration factors). The regenerant presently used is a pH 9.5 solution containing 7.5% NaCl and a mixture of Na2C03/NaHC03. expressed as 2.5% NaHC03.

Jan 1, 1980