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By K. L. Komarek

Based on theoretical and experimental evidence a discussion follows of the behavior of phosphorus -bearing iron ores in the R-N Direct Reduction Process and suggestions are made of methods of reducing the amount of phosphorus in the metallic end product. In ferrous metallurgy a direct reduction process is one in which iron ores are reduced to metallic iron with gaseous or solid reductants without the appearance of a liquid phase. A number of attractive features have induced several companies and government agencies to invest in the development of direct reduction processes. A summary of all direct reduction processes up to 1954 has been given by Barrett,' and Wiberg,2 and Willems3 have reviewed the most recent developments in this rapidly expanding field. Many difficulties have been encountered in direct reduction processes and the nature of these difficulties has varied from process to process. One problem common to almost all of them is the removal of phosphorus which is one of the reasons for the rather pessimistic outlook given by some government publications4'5 to direct reduction processes. In this paper an attempt is made to give a theoretical explanation of the variations in phosphorus removal observed in the R-NY Direct Reduction Process. However, many conclusions are general enough to be applicable to other processes. Most iron ores treated by the R-N process yield products lower in phosphorus than the original ore. A qualitative account of the factors has been given by Stewart, Reed, and Herasymenkoe but the erratic removal of phosphorus from some ores and the general importance of this problem make a more careful analysis of the theoretical aspects desirable. In the R-N process mixed ore or balled fines, ex-

Jan 1, 1963

By P. E. McKinney

Developments in engineering during the past decade, particularly as applied to marine construction, mining machinery and other purposes in which corrosion offers a serious problem, have created a large demand for a non-ferrous metal highly resistant to corrosion and at the same time useful in general construction work as a substitute for steel without materially decreasing the factor of safety or increasing the weight of the various parts over that ordinarily used in the case of mild steel. To obtain the combination of desired properties many compositions have been proposed and used with excellent success, but at the present time probably the most popular and most widely used combination is the non-ferrous alloy commonly called manganese bronze. This is nothing more than a high brass to which have been added, by the proper method of alloying, comparatively small percentages of aluminum, iron, or manganese with the definite purpose in view of strengthening the alloy and rendering it more dense and close-grained than the average yellow-brass casting. In the manufacture of manganese bronze a great deal has been said about the importance of using only the highest grades of raw material and the beneficial or detrimental effects, as the case may be, of various impurities, as well as the importance of adding the ingredients according to various formulas proposed; but in most of these cases the literature on the subject has dealt principally with the manufacture of this alloy from virgin metals and raw materials of the highest purity. It is the purpose of this paper to deal particularly with the possibilities that lie in the proper development of methods for manufacturing such an alloy by more economical methods than those which have usually been discussed in other literature on the subject. Shortages have recently existed in raw materials needed for many products entering into the various branches of engineering work, particularly the non-ferrous metals, and during the next few years of reconstruction the country will be flooded with many

Jan 1, 1919

By Ferdinand S. Ruttmann

There is now in use at the mines of the Chateaugay Ore and Iron Co., at Lyon Mountain, New York, an ore-concentrating machine or jig, which, in view of the increasing attention given to the subject of concentrating lean ores of iron, seems worthy of notice. This Conkling Jig, as it is called, is not entirely unknown, having been used at several places with more or less success; but as yet, I believe, no drawings of it or records of its work have found a place in print. Although the jig will be found to be merely an adaptation of old forms, there are several points which deserve attention, particularly the method of central discharge, of freeing the bearings from grit, and the rotation of the sieve or screen. The ore-body at Lyon Mountain consists of a bed of rather compact, granular magnetite, occurring in a gueiss formation. The side walls of the ore-body are not sharply defined, the ore 011 either side becoming gradually poorer as the distance from the central point of the body increases. It is this lean ore, which, before the introduction of the jigs, was thrown away as waste, that is now concentrated. The material treated conseqnently consists of magnetite, intermixed with the component parts of gneiss, viz. quartz, felspar, hornblende, and mica. Grains of trap also form part of this material. These come from dykes of trap, which cross the ore-body at intervals. The ore which is to be concentrated usually contains from 30 to 40 per cent. of metallic iron. It is first crushed to the size of two inches, or less, by two large Blake crushers. The material from these crushers passes by a shute lined with screens, having holes 2 inches in diameter, to a second set of four crushers, set so as to close to one inch. The product from this set of crushers, together with that which passes through the screens in the shute, is then taken by an elevator to the top of the mill, and passed through a revolving screen, perforated with ) inch holes. The ore which passes through the screen goes to the jig-hoppers ; that which passes over goes to a third

Jan 1, 1888

By John V. Beall

Given: One large, but dated open-pit copper mine and processing plants, down about one third in production capacity in decade because of declining ore grade. Solve for: Restoration of former peak capacity without further losses during period of reconstruction. That is the problem that Kennecott's Utah Cop- per Division began solving in 1963. Most of the work went to a task force of engineers, several of whom were plucked out of line jobs and assigned to the so-called "Expansion Project" for the duration. There was no doubt from the beginning that effective cooperation between Expansion Project engineers and operators was critical to success, and personnel was chosen accordingly. This foresight paid off. The Expansion Project is all but complete, and the Utah Copper Division is returning to its rated capacity of 300,000 tons per year of copper metal.

Jan 6, 1967

By J. M. McCormack, R. K. Saxer, J. R. Myers

ThE Knudsen effusion technique was used to determine the chemical activities of copper and platinum in binary Cu-Pt alloys in the temperature range 1542" to 1673°K. Wiebke and Matthes1 previously obtained chemical activities of copper and platinum in this system at 673° and 923°K by the electromotive-force measurement method. They reported that the copper activities exhibited negative deviation from Raoult's law at all compositions. The chemical activities of platinum were found to change from a positive to a negative deviation at 923°K. Myles2 recently studied this system in the temperature range 1265° to 1356°K by means of the torsional-effusion technique. His results indicated that both copper and platinum exhibited negative deviation from ideality at all compositions. The use of the Knudsen effusion technique to obtain the vapor pressure of metals and alloys is well-known.3 In this work, Knudsen cells were fabricated from seamless tantalum tubing of 1-in. OD and 0.020-in. wall thickness; cell bases and covers were cut from 0.010-in.-thick tantalum sheet and welded to the cells in an argon atmosphere. Orifices were drilled and reamed to approximate a knife-edge of 30-deg included angle. Calculation based on Balson's4 derivation showed the orifice to be nearly ideal. All temperature measurements were made with a Leeds and Northrup disappearing-filament-type optical pyrometer at the orifice of the cell, which closely approximated black-body conditions and eliminated the need for emissivity corrections. Details of the experimental techniques used, and the necessary correction factors required during this investigation are essentially those previously described.5,6 Before investigating the Cu-Pt alloys, vapor-pressure measurements were obtained over specimens of pure (OFHC) copper. The pure-copper data5 served to assure the accuracy of the experimental apparatus and technique.

Jan 1, 1967

THE paper on "Specific Efficiency of the Blast Furnace" by Richard Franchot, which was pub-lished in the September issue of MINING AND METALLURGY, was presented for discussion at the Pitts-burgh meeting. The session opened with a discussion among S. P. Kinney, Mr. Franchot, and J. N. Reese as to the methods and results in sampling for cyanides in the blast furnace. This is covered in detail in writ-ten discussion below. T. T. Read objected to the use of the term specific efficiency as likely to be confusing. The blast furnace has to perform the function of reducing Fe, 03 to Fe as well as that of fusing the metal and, since the reduc-tion of Fe, 0? involves a CO equilibrium, it seems mis-leading to calculate efficiency on the basis of burning the , all carbon to CO? since it is not possible. Mr. Franchot replied that he used the term in the sense defined by Richards in his "Metallurgical Calculations;" but a subsequent search failed to reveal the term in Richards, who says (page 245, 1st edition): The practical conclusion is that a blast furnace generates in itself not much over 40 per cent of the calorific power of the fuel used, and rejects nearly 60 per cent; by using part of the waste gases to heat the blast, however, some of this rejected heat, to an amount representing net 5 to 10 per cent of the calorific power of the fuel used, is returned to and injected bodily into the furnace, thus rendering available for the purpose of running the furnace about 50 per cent of the calorific power of the fuel as a maximum. The efficiency with which the furnace applies this 50 per cent usefully to the objects of the reducing and smelting is another question for investigation.

Jan 2, 1927

By Ellis Clark

Within the last ten years the progressive party of China, headed by Li Hung Chang, the Viceroy of Chi-Li, has been making great efforts to develop the mining resources of that country, and particularly those that are within reasonable distances of the sea-board. Attention was first paid to the coal-deposits, especially those at KaiPing, which have been placed on a profitable basis with an output of 1500 tons per day, under the energetic management of Mr. Claude Kinder, M.I.C.E., and the successful financiering of Tong King Sing. These coal-mines were described in a report by Kwong Yung Kwang, edited as a paper for the Institute (Duns., xvi., 95.) The attention of the leaders of the progressive party has for the past five years been turned also toward the development of the precious and related metals—gold, silver, copper and lead. De-

Jan 1, 1891

By T. B. Gyles

Zinc is made by the National Smelting Co. and its associates by both the horizontal retort process and the vertical retort process developed by the New Jersey Zinc Co. This paper deals only with the horizontal retort practice at Avonmouth. That the horizontal retort process does survive in all countries in some form or other is due to at least partial success in overcoming some of the inherent difficulties of the process. The horizontal retort furnaces ran into considerable difficulties when the product of the selective flotation of mixed lead and zinc ores became the normal material for treatment. It is necessary, therefore, to make some reference in connection with the process to the preliminary treatment of the ore prior to distillation.. Therefore we include some small reference to this aspect in our description. Furnace Design and Structure Of the types of furnaces in operation at the company's various works, those at Avonmouth are perhaps more typical of the trend to utilize large units, with a subsequent saving in costs, such as heating and supervision.

Jan 1, 1937

By J. B. Morrow, D. H. Davis

THERE are two general approaches to the problem of increasing profits from an operation. One is to lower expense; the other is to raise income. Mechanical preparation of coal may be used for either purpose but a prudent consideration of many details must precede any decision lest the results be negative instead of positive. It is quite possible that any net gain will result from a combination of the two. Since mechanically prepared coal invariably is a better product qualitatively than a hand-picked coal from the same mine, it is a reason¬able expectation that the customer will be willing to increase the pro¬ducer's income by paying a higher price. Or there may be the possibility that a combination of mechanical mining plus mechanical cleaning will give a lower over-all production cost for the coal in the railroad car. More likely, there will be found a combination of these two factors. From the customer's point of view, the competitive delivered cost per B.t.u. considered in relation to such incidental factors as dust nuisance, handling properties, ash disposal, and ash fusibility determines what he will pay. In a bulk tonnage product such as coal, freight is a very considerable part of the delivered fuel cost, and obviously freight paid on incombustible ash has no economic attractions.

Jan 1, 1943

By W. B. Hall, Joy D. Lewis

Mine-run ore is received at Vitro in gondola cars and fed directly to a Cedar Rapids impact crusher. Following screening, the undersize travels through a recently installed three-stage sampling plant where successive cuts are executed by conventional Geary-Jennings type cutters to produce a final sample of 1 lb per ton of raw ore fed. Crushed ore is transported to one of three storage silos or to stockpile, depending upon grade and type of amen- ability. This permits the blending of a mill feed with some degree of consistency. Final grinding is accomplished in one of two closed circuit ball mill-classifier systems allowing simultaneous processing of two basic types of ores. High acid consumers may be leached separately in the required environment. Part of the free acid remaining can then be utilized by an ore stream entering later whose component ores require much less free acid for leaching.

Jan 11, 1958

NEW MEMBERS The following list comprises the names of those persons who became members during the period Oct. 10 to Nov. 10, 1914: Members ADDAMS, CHARLES EDWARD, Asst. Supt.. . Ray Consolidated Copper Co., Ray, Ariz. ALEXANDER, HARRY H., Asst. Mgr. and Mgr., American Smelting & Refining Co., Maurer, N. J. ALLING, MARK,N., Min Engr Downieville, Sierra Co., Cal. ANDERSON, LESLIE DOUGLASS, Supt U. S. Smelting Co., Midvale, Utah. ATKINS, WILLIAM, JR., Sec'y Kingwood Coal Co., Howesville, W. Va. BLAKE, TRUE WALTER, Min. Engr Rombauer Coal Co., Novinger, Mo. BRACKETT, GEORGE SYLVESTER, Supt... Pittsvein Coal Co., Flemington, W. Va. BRAINERD, HOWARD STANFORD, Met Ingersoll-Rand Co., Phillipsburg, N. J. BROWN, THOMAS J., Genl. Supt., Nova Scotia Steel & Coal Co., Sydney Mines, N. S., Canada.

Jan 12, 1914

By R. G. Ward, P. L. Sachdev

Using an improved maximum bubble pressure technique, the densities of iron silicates at 1400°C have been measured under nitrogen. At the wiistite composition the density has been measured by bubble-blowing experments with both argon and nitrogen and calculated from the measured volume of a known mass of melt under nitrogen. The densities under nitrogen are significantly different from those measured under argon for melts containing less than 28 wt pct SiO2. THE constitution of liquid slags is not well understood, largely because no single property or parameter can be measured which gives conclusive evi- dence of the types and packing of the ions present. Of the many property measurements which can provide information leading to a picture of the constitution of slags, density gives the most direct evidence and has been studied extensively. The work reported here is part of a program of study of densities in multicomponent melts in which the iron oxide-silica system is the solvent. These melts are important as they are fundamental to basic steelmaking, and they allow the study of basic silicate compositions which have hitherto been largely neglected. As considerable disparity exists

Jan 1, 1965

By Persifor Frazer

At a time when all those interested in the iron trade are carefully scanning the horizon for new sources of the raw material, a few words concerning a field, which though not new, has not been hitherto fruitful of statistical information, may be deemed appropriate at this meeting. The district alluded to is the belt of the Middle James River, or in other words, that portion of the ferriferous belts of Virginia lying between Josua Falls and the little settlement of Norwood, in the counties of Amherst and Nelson, and on the left bank of the James River. This region shows unmistakable signs of developing a very considerable market for iron ores and for iron in the future, as well as a tempting appearance of possible productiveness in the former. It, is extremely hazardous to deal in generalizations as to the productiveness or non-productiveness of these measures without a more thorough development than has yet been attained. It is true that they probably constitute an horizon whence comes a part of the marvellous mineral wealth of the northern peninsula of Michigan. But

Jan 1, 1883

By W. Rostoker, S. A. Spachner

FOLLOWING the discovery of the w transition phase in certain titanium-chromium alloys by Frost, Parris, Doig, and Schwartz, much interest has centered on the alloys in which this phase is found and its mode of precipitation. The w phase has been found in alloys of Ti-Cr, Ti-Fe, Ti-Mn, Ti-MO,2 and Ti-v.3 The temperature-time-transformation characteristics have, as yet, not been determined for most of these. In this study, such transformation characteristics have been investigated for two heat-treatable titanium alloys known to exhibit transition phase phenomena. The alloys chosen, Ti-8Cr and Ti-13M0, are representative of two classes of binary equilibrium systems. In the

Jan 1, 1959

By E. Buehler, R. H. Willens

A Hew melting technique has hem adapted to the rapid quenching of- alloys from the liquid state. The inelting method has no limitations on the alloys investigated for there is no reaction with crucible materials and the most refractory materials are easily melted. The vate of heating is so rapid that alloys which have a high vapor pressure constituent can be melted with a minimal loss in material. Several new superconductovs have been discoveved by vapid quenching of lolten alloys. THE rapid quenching of alloys from the liquid state has led to the discovery of many new metastable phases. The methods initially used were limited to alloys which did not react with crucible materials.1,2 There was also the unmentioned limitation in tem- perature. Alloys with melting points much greater than 2000°C could not be melted in the rapid-quench apparatus. Recently, there have been successful attempts to rapidly quench reactive alloys by Moss et at. and Matthias Moss et al. injected powdered material (325 mesh) into a high-temperature plasma and the high-velocity molten droplets impinged on a cooled copper plate. The technique innovated by Matthias was to melt the alloy in an arc furnace and splatter it against a copper plate by means of a high-velocity gas jet aimed at the melt. I) FAST COOLING APPARATUS The creation of a metastable phase in a given alloy system by rapid cooling from the melt is contingent on the quenching rate. Some alloys require very slow rates while other alloys require the ultimate in quenching rate. At the present time, the vertical-gun technique of Duwez and willens' has demonstrated, in practice, the highest quenching rates and thus the best

Jan 1, 1967

By John W. Frey

[Minerals, generally of great geological age, are to a very large extent the material basis of what we know as modern civilization. In most of the so-called civilized world the use f minerals has become such a commonplace that it is easy to se sight of their importance. It was the use of minerals, obably more than anything else, that made it possible for e American people to expand from the Atlantic seaboard the Pacific in a little over one hundred years. As the 1 to use the natural wealth at hand constitutes a funda¬ental element in American life, there seems to be justification for the thought that American geography is largely mineral geography. Of all American environmental reactions, the most striking are those which have come about through the use of the metals and the power fuels. If we turn to the ancient industry of agriculture, we find very little that is unique in North America except those developments which have come about through the use of machinery and transportation, both of which are contingent upon the use of minerals. Practically every crop now grown n North America was grown in some part of Europe before merica was discovered. One can point out exceptions to statement but in general it is true. Analysis of the es of North American agriculture shows that the outstand¬ characteristics are: regional specialization (i.e., the Economic Geographer; Chief, Petroleum Section, Minerals Division, u of Foreign and Domestic Commerce.]

Jan 1, 1932

By C. A. Mitke

The United Verde Extension mine is located in the Jerome mining district, on the eastern slope of the Black Hills, approximately northeast of the town of Jerome, Yavapai County, Arizona. The ore deposit may be termed a replacement in Yavapai schist. This schist is one of the oldest formations in the district, being probably of volcanic origin, and has been folded and faulted and contains intrusions of diorite and quartz porphyry. It is believed that the mineralization followed the porphyry intrusions and replaced the country rock; this was followed by erosion and a period of secondary enrichment, all completed in pre-Cambrian time. Later sediments of sandstones and limestones, to the depth of approximately 600 ft. (182 m.), were laid down, followed by volcanic flows. Faulting and erosion again took place, resulting in the present complicated arrangement of the strata. Prospecting, therefore, is very difficult, because the sediments practically cover the mineralized areas. This necessitates the sinking of deep shafts, cross-cutting, and, in some instances, diamond drilling to learn something of the various relations of the different formations and the occurrences of intrusions associated with ore deposition. The locating of new orebodies, therefore, is beset with innumerable difficulties. EARLY MINING METHODS The two orebodies constituting the principal resources of the company are known as the small orebody and the Bonanza, or large orebody. These are about 150 ft. (45 m.) apart, and while they appear to be distinct orebodies may later prove to be connected. The character of the ore, the general associations of the porphyries adjoining the orebodies, and other characteristics, both in the ore and general environment, are very similar. The small orebody was the fist to be discovered and was mined for some time before the Bonanza was found. At first, a large amount of ore was extracted by means of development work, but as the smelters treating this class of ore were located from 60 to 400 mi. (96 to 643 km.) away, only the highest grade yielded a fair profit and it became necessary to do selective mining. The main workings

Jan 1, 1920

By Anthony Anable, J. V. N. Dorr

When separate treatment of sand and slime by cyanidation was the rule rather than the exception, as now, and when gravity concentration, rather than flotation, was the accepted method of dressing copper, lead, zinc and other base ores, classification was a separate step in ore treatment. Today, however, the picture is much different. The trend toward all-slime treatment in cyanidation and flotation has made fine closed-circuit grinding essential, and the mechanical classifier is of equal importance with the mill in the preparation of an ore for its treatment. Actually, a mill and classifier are a unit, a variation in either affecting the desired results. In developing this thesis—the mutual interdependence of the rotary mill and the classifier in modern fine-grinding practice—it would be well to consider first the different types of classifiers and mills in use today, their scope and limitations and the factors governing their selection. From such a basis as this a logical approach may be made to modern closed-circuit fine grinding, the evolution of multiple-stage grinding practice, the relation of the classifier to the mill and, finally, the trend to higher and higher circulating sand loads in the mill-classifier circuit. Such data as are germane to the subject will be given to support the thesis advanced. Mechanical Classifiers Theory.—Stokes' law, applicable to the uniform slow motion of a rigid sphere in a viscous fluid of infinite extent, states that the velocity of a particle settling under the influence of gravity is a function of the square of its radius: _ 2 g(ds - de)?2 v =9 S Where V = velocity of particle in cm. per see. g8, acceleration due to gravity d8, density of particle de, density of fluid ? = radius of particle S = viscosity of fluid

Jan 1, 1935

By David R. Mitchell, R. B. Hewes

MANY processes for cleaning coal that are in use depend primarily on physical properties of coal and refuse other than specific gravity and surface conditions relating to froth flotation. These properties are shape, coefficient of sliding friction, resilience, friability, magnetic susceptibility, and electrical conductivity. In many of these processes specific gravity does have some effect and many separators are designed to utilize more than one of the physical properties cited. Although the processes described herein do not have a widespread application, yet for specific coals and specific conditions, they are economically important. A problem confronting many coal-mining districts is the marketing of the slacks or screenings and dust passing the final sizing screens. Processes in commercial use installed primarily to increase the form value, and hence the market value, of these slacks and dusts include briquetting, packaging, and low-temperature carborization. MECHANICAL PICKERS Machines utilizing shape, fictional resistance, and differences in resilience of coal and impurities are usually called mechanical pickers. They require a closely sized feed, therefore their use is confined to the pea, nut, and egg sizes. Various types of these devices are described by Berrisford, 1, 2 Taggart, 3 and Peele. 4 Shape In general, coal differs in shape from its accompanying dirt throughout the range of commercial sizes. Coal, breaking into roughly, cubical particles, contains a greater number of axes that are approximately the same length than does the dirt. The latter, consisting of pieces of slate and shale and lenses of pyrite, is flatter in nature. Further, flat coal often has a dirty, slaty appearance, even though of high quality. Mechanical pickers known as flat pickers, or "flatters," are widely used in the Pennsylvania anthracite region to remove flat coal from the final clean coal. This practice greatly improves the appearance of the final market product.

Jan 1, 1943

By A. Matsubara

Jan 1, 1922