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By Howard N. Eavenson

Waste of coal, or perhaps more properly the percentage of its recovery in mining, has keenly interested me during an experience of over a half century in coal mining. In the early part of that time and until a few years after World War I the use of better mining plans and supervision resulted in an increased recovery. Since then, and particularly since controlled prices have been effective and mechanized mining has been extensively practiced, the tendency has all been toward lesser recovery in mining. The purpose of this paper is not to criticize the methods being used, which after all are the result of economic forces, nor to point to any particular mining method or to any locality where the best recovery is obtained, but to call attention to the tremendous waste of our national coal resources that is constantly continuing. A possible method of reducing this loss will be suggested, but without any illusions that it will be followed or that such attention will be paid to it. Average Recovery The actual average percentage of recovery of coal in the ground is not known. Many papers giving figures of recovery have been published but no definite base of measurement has been agreed upon by those presenting the data. As an example, the Pittsburgh bed can be considered—it has produced a greater output than any other and has been sold or leased at higher prices in place than any other coal bed. Over a large part of its area where high prices have prevailed it has been customary for many years to draw pillars. In these mines it has been usually assumed that the average recovery was higher than in other beds and percentages of recovery of 85 to 95 per cent are usually said to be realized. In all of these mines, however, it has been customary to leave from 4 to 8 in. in the bottom, and 10 to 16 in. in the roof; thus from 14 to 24 in. of coal has been left in the mines out of a total seam thickness of about 96 in., or 15 to 25 per cent of the total coal. No attempt is made to mine this coal for metallurgical purposes, owing to its impurities, although this unmined coal is of excellent quality and better than much of the coal used for steam purposes. If we add to this discard the coal usually lost in mining and those parts of the bed 'that must be left because of bad seam conditions, barrier pillars, reservations for buildings, gas and oil wells, one can easily see that the actual recovery from this bed cannot be more than 65 to 75 per cent. In addition, the rooster or rider or wild coal over the mining bed—often 3 to 4 ft. of coal, high in ash and sulphur but still good steam coal—is hardly ever mined, nor is any attempt made to mine it. It is safe to say that from a broad economic viewpoint not more than 50 to 60 per cent of the fuel value of this great seam is actually being recovered.

Jan 1, 1947

By J. E. Powell, F. H. Spedding

WHILE rare earths are reported to be widely distributed in nature and are not really rare," in practice, there are only a few minerals which are sufficiently rich in rare earths to serve as practical sources. Perhaps the best known of these is monazite which is a phosphate mineral containing rare earths and thorium. This mineral occurs as a dense brown sand in gravel beds and is particularly rich in the light rare earths of the cerium subgroup. This mineral is processed commercially for its thorium, cerium, and lanthanum content, and, consequently, furnishes rich concentrates from which neodymium, praseodymium, samarium, europium, and gadolinium may be obtained. Unfortunately, monazite is rather lean in rare earths heavier than gadolinium. A second mineral which is rich in the light rare earths is bastnasite, a fluoro-carbonate. Extensive deposits of this ore have been discovered in the western United States and have received considerable newspaper publicity in recent years. While bastnasite is very rich with respect to cerium, lanthanum, and neodymium, it contains even less heavy rare earths than does monazite. One of the better sources of heavy rare earths of the yttrium subgroup is gadolinite, a black silicate rock from which the rare-earth content can be extracted readily by acid leaching. It is obtained chiefly from Norway at the present time, although there are known deposits in the United States. Other sources of heavy rare earths include fergu-sonite, euxenite, and samarskite which are refractory tantalo-columbate ores. These minerals require caustic fusion or reduction to carbides with carbon before the rare-earth content can be extracted. All of the minerals which are rich in the heavy rare earths contain yttrium as a major constituent. After the rare earths have been extracted as a group from an ore by chemical means, it is generally convenient to precipitate them from acid media with oxalic acid in order to eliminate certain non-rare-earth impurities such as iron, beryllium, etc., which are usually present. The oxalate can then be readily ignited to R2O3. The oxide can be dissolved in acid and is the starting point for subsequent separation into the pure components. Perhaps the principal reason why the rare earths have not been studied as extensively as other elements of the periodic table, whose natural abundances are comparable, is that they are extremely difficult to separate from each other by the usual chemical means. Prior to 1945, the separation of one trivalent rare earth from another was a laborious process. All separations were based on repeated fractionation processes, i.e., fractional precipitation, fractional decomposition, fractional crystallization, etc. These processes were repeated from a few hundred to many thousands of times in order to obtain individual rare-earth salts of reasonable purity. Of course, mention should be made that, in the few cases where a rare earth could be oxidized or reduced to a valence state other than three, more conventional chemical means could be utilized to separate the oxidized or reduced ion from the other normally trivalent rare earths. The ionic states which deserve special mention are CeIV, SmII, Eu11, and Yb11. When it is possible to remove an element of the series efficiently, due to an optional valence state, its immediate neighbors also become easier to isolate. For example, binary mixtures of lanthanum and cerium, and praseodymium and cerium can be obtained by a relatively small number of fractional operations. The tetravalent state of cerium then allows the complete resolution of the binary mixtures by ordinary chemical means. Although the tetravalent state of cerium has been known for a long time, the divalent states of samarium, europium, and ytterbium were not used extensively in separations prior to 1930 because they are relatively unstable in aqueous media.'-" No attempt will be made to give a comprehensive review of the extensive literature dealing with the separation of rare earths. Rather, this paper will be confined to a review of those methods which have been developed at Iowa State College during recent years, and which have proved extraordinarily successful for the isolation of highly pure rare earths in quantity. It was obvious that, if pure rare earths were to become generally available, methods would have to be developed wherein the thousands of fractional operations made necessary by the similarity of rare-earth properties could be performed automatically. The development of chromatographic techniques and ion-exchange resins appeared to offer a mechanism by which this objective could be accomplished. A number of early attempts were made to separate rare earths by these means; for example, Russell and Pearce12 passed a mixture of rare earths through a cation-exchange column and reported

Jan 1, 1955

He took a great interest in technical matters and his inclination was strongly toward research investigations. At the same time he was effective in manual and mechanical work and was generally found working side by side with the men under his direction. His nature was unselfish and he was extremely popular socially. He was a member of the Coeur d'Alene Commandery, Knights Templar. Stanly A. Easton. Lieutenant.Louis Baird Louis Baird, a Lieutenant in the Royal Field Artillery of the British Army, died on the battlefield in 1915. Lieutenant Baird was born July 28, 1880, at Stirling, Scotland. His technical education was obtained at King's College, Melbourne, Australia, in 1893 to 1895, and at the Technical College at Glasgow, Scotland, in 1897 to 1900. After an apprenticeship with the Mexican J. & 8. Rec. Co. of Mexico, lasting from 1900 to 1903, he became mill superintendent for the Cia. Minera Benito, at Juarez, Zac. During the year 1905-6 he was assistant manager of the Caridelaria y Anexas, at Pinos, Zac., and from 1906 to 1907 was engineer with the Cia. Minera Jalisco, San Sebastian, Jalisco. At the time of his admission to the Institute, in 1908, he was practising as a mining engineer at Etzatlan, Jalisco, Mexico. For the next four years he practised his profession in the City of Guadalajara, Jalisco, removing, in 1913, to Ixtlan del Rio, in the State of Tepic. It was from here that he returned to England to put his services at the disposal of the British Government. The Institute is not definitely informed as to how, where, or when Lieutenant Baird met his death. iCaptain John H. Ballamy John H. Ballamy, Captain on the Regimental Staff of the 103d Engineers, was killed near Fismes, on Aug. 9, 1918. Captain Ballamy was born at Plvmouth. Pa.. in 1886 and graduated from' the High School of that town in 1903. In the following year he began work as a coal miner, and at the same time began the study of mining engineering in the evening and any other spare time. He continued this diligent and energetic practice for many years. For sixteen years he continued in the employment of the Delaware, Lackawanna & Western Rai1roa.d Company's coal mining

Jan 1, 1920

By A. Sauveur

In an important paper on The Critical Ranges of Pure Iron presented at May, 1913, meeting of the Iron and Steel Institute…

Jan 1, 1915

By Joseph Pogue

OVER a period of years the writer has presented a number of studies1 on various aspects of proration, in a progressive attempt to analyze critically and constructively the economic complexities of this interesting institu-tion, which in a decade has revolutionized the economics of oil production in the United States. In the course of the investigations leading to these papers, the changing nature of proration and the principles under-lying its evolution have gradually become clear, so that it is now possible to depart from the analytical method and to construct a synthesis of the steps that, if furthered by the industry, should carry proration past the economic hazards that still surround it to the goal of maximizing the value of the petroleum resource to the industry and the public alike. NATURE OF PRORATION Proration literally means the allocation of demand among competing producers on a pro rata basis, but the term now carries a much broader significance for it is employed to describe the entire process by which the production of crude oil in the United States is regulated. There is naturally much confusion of thought on the subject, for proration is an evolving system of control based upon principles of conservation and equity and embracing a body of practices that are tending to adjust themselves to the needs of the situation but are subjected to varying and divergent influences in the process. As it is now constituted, proration is a planned production measure designed to prevent waste, insure ratable takings, and balance supply and demand. The procedure is administered by State regulatory bodies through use of the police power of the States under authority of State conservation laws; the practice is supported by a considerable degree of voluntary conformance on the part of operators; and the Federal Government has accorded its cooperation by providing advisory quotas, circumscribing imports, checking movements of hot

Jan 1, 1939

Jan 1, 1945

By J. B. Goddard

Crystallization of ammonium paratungstate (APT) is frequently the last effective purification step in producing high-purity tungsten. However, crystallizer mother liquors are often several times higher in tungsten than predicted by the solubility of APT. The formation of heteropoly anions, particularly those containing phosphorus and silicon, is largely responsible. Solubility of tungsten in APT mother liquor can be linearly correlated with the concentration of these and other impurities. The problem can be overcome by direct treatment of the crystallizer feed solution with aluminum sulfate. By appropriate treatment, the aluminum hydroxide flocculates and is easily filtered, resulting in a purified low-aluminum crystallizer feed from which high APT yields can be attained.

Jan 1, 1985

By William Fraser

SINCE the operative word in the subject on which I have been asked to speak is "international," I need hardly emphasize before such an audience as this that it is one which calls for some discretion on my part at the present juncture of world affairs, since, in some respects, it may not be devoid of a controversial aspect. For though the war is over, it has left behind it a sorry state of health in the political and economic complex of the world we live in; and however different may be the impact of these factors on each of us, yet none of us can any longer hope to devise a system or policy to escape from much of its controversial heat, or evade the obligation of doing what we can to diminish it. I would like, therefore, to consider with you how one great form of world enterprise whose range is coextensive with material civilization itself-that is, the Petroleum Industry-can make and is competent to make, a contribution to international health; for it is now an agreed commonplace that oil is arterial in the world's system and we need no telling that a healthy body needs healthy blood. Before embarking on my subject, let me assure you that I have no need to be told that this country before all others-and for obvious reasons is the major sounding board of opinion in matters affecting most aspects of the petroleum industry-technical, economic, national and international (but, may I please add parenthetically, not to the exclusion of quite a

Jan 1, 1947

By Wallace W. Key

Chalk is a natural calcium carbonate occurring as the remains of soft, friable, minute marine organisms. Whiting can be either finely ground calcium carbonate prepared from chalk, marble, or limestone or the product obtained by chemical precipitation from a solution or suspension containing lime. Until relatively recently, whiting made from limestone was termed "whiting substitute," but it is now usually designated as limestone whiting. Precipitated calcium carbonate, sometimes called "precipitated whiting" or "precipitated chalk," is a finely divided calcium carbonate product obtained by chemical precipitation from a solution or suspension containing lime. Considerable quantities of precipitated calcium carbonates are produced from many chemical processes. Naturally occurring calcium carbonate in a variety of crystalline forms and in all degrees of chemical purity forms a substantial part of the earth's crust. Exactly where a chalk grades into a marl or calcareous shale through increase of clay or silt or into a hard limestone through consolidation and crystallization is difficult to determine because no rigid specifications have been promulgated for classifying them. Composition and Properties Once considered to be amorphous, chalk was later found to be cryptocrystalline. In the pure state it consists entirely of CaCO3, but many deposits are impure. When impurities are removed and the material is reduced to a finely divided state, it is known as chalk whiting. Much confusion attends the use of the term "chalk" as well as the classification of whiting materials. For instance, blackboard chalk is not necessarily chalk but is sometimes plaster of paris or a form of talc. Colored "chalks" may be true chalk colored and compressed with a binder but are probably such materials as hematite, clays, or carbonaceous matter. The term whiting was applied exclusively to the product derived from true chalk before World War I. Chalk imports were difficult to acquire during World War I, and whiting substitutes, a term applied to the products derived from natural rock deposits and precipitated calcium carbonate, were introduced. Substitute whitings were not acceptable at first, but it was found that blending true chalk with substitutes often created an improved product; eventually by selection of limestone and finer grinding, products not only acceptable, but for some uses superior to chalk whiting, were developed. Gradually the term "substitute" was dropped because chalk whiting had lost its importance, being largely supplanted in the United States by other whiting materials. Whiting is now made in ever-increasing quantities from limestone, marble, dolomite, marls, vein calcite, oyster-shell, as well as primary and byproduct precipitated calcium carbonates. Distribution of Chalk Europe-In England, France, Belgium, Denmark, and other European countries highpurity chalk occurs in extensive beds. The Cretaceous period, or the "age of chalk," in geologic history receives its name from the great deposits of chalk exposed on either side of the English Channel. It has been estimated that oceans in which chalk and allied deposits were formed covered more than 500,000 square

Jan 1, 1960

THE bellows are important and necessary agents in most melting processes. In addition to seeing that these have sufficient soft cloth, extend far and wide, and are of good design, including good valves and good long tubes, and that they cannot break and lose the air received, it is very important to give attention to their installation so that they may easily effect their purpose. Therefore I now wish to proceed by noting some common devices for moving them, both with water and with man power, so that you may make use of them as the need arises.

Jan 1, 1942

By F. J. Dunkerlery, V. Damiano, J. Fulton, F. Pledger

Grain-growth and recrystallization characteristics of a commercially pure zirconium prepared by the iodide process are reported. Grain growth from 640° to 800°C was continuous once initiated and obeyed D = kt". Recrystallization of zirconium occurred at temperatures of 450° to 550°C after deformations of 20 and 50 pct. Hardening from partially soluble inclusions prevented determination of the absolute rates of recrystallization, but the relative rates of recrystallization obtained are useful as a guide in fabrication practice. BASIC information needed as a guide in the hot and cold working and annealing of metals includes recrystallization and grain-growth data. A search of the literature revealed no such information for pure zirconium. This is a report of practical grain-growth and recrystallization results obtained for a commercial grade of pure zirconium on a project sponsored by the Office of Naval Research. In this work, isothermal grain-growth curves were obtained at five temperatures from 640" to 800°C inclusively; while recrystallization curves have been determined at 450°, 500°, and 550°C for the metal at the deformation levels of 20 and 50 pct. In addition to the usual variables of temperature, time, and deformation, distribution of the second phase found in all commercial grades of iodide zirconium is also treated as an important factor in these grain-growth and recrystallization studies. In conducting this work, two properties of zirconium were particularly pertinent in dictating experimental conditions. First, since zirconium undergoes a transformation from the a close-packed hexagonal form to the ß body-centered cubic form at 862°C, no recrystallization or grain-growth studies were made above 800°C. Second, because dissolved gases (oxygen, nitrogen and/or hydrogen) increase the hardness and lower the ductility of the solid metal, all annealing treatments in this investigation were carried out in vacuum or in a helium atmosphere. Materials and Methods The zirconium used in this investigation was prepared by the Foote Mineral Co. by deposition from its iodide. A spectrochemical analysis of the metal showed the following composition in weight pct: Hf, 2.1; Mg, 0.012; Fe, 0.035; Si, 0.095; Ti, 0.023; Al, 0.037; Mo, trace; Ni, trace; Cr, trace; Ca, 0.006. Conventional metallographic procedures involving hand polishing on wet metallographic papers, followed by final polishing on fine, levigated alumina on gamal cloth and a medium speed wheel were used throughout this investigation. Grain boundaries were revealed with modified Tucker's etch containing 20 parts glycerine, 2 parts hydrofluoric acid, and one part nitric acid. Grain-Growth Procedure: Three lots of zirconium, designated here as series A, B, and C were prepared for the grain-growth studies as follows: Series A was prepared by cold swaging the % in. as-deposited rod to a 3/16 in. final diameter, followed

Jan 1, 1952

Just three years after researchers announced its development, Dravo is putting the finishing touches on a new $60-million Thiosorhic lime mine/kiln complex near Maysville, Ky. Electric utilities in western Pennsylvania and Ohio have already signed long-term contracts for over three-quarters of the projected 907 000-t/v (1-million-stpy) production. Thiosorbic lime, a flue gas desulfurizing agent, proved in industrial testing that at high emission levels (greater than 3000ppm SO2) it could be twice as effective in SO2 capture as conventional lime, while eliminating the major problem of scaling and plugging of scrubber equipment.

Jan 4, 1977

WHAT was certainly the greatest event of January, and perhaps it will prove to be the greatest of 1923, or even of the next decade, was the meeting of the premiers of the principal Euro-pean powers in Paris on Jan. 2, to consider what should be done with respect to German reparations. The French and British were unable to come to any agree-ment, and the conference broke up on Jan. 4. The French and British parted friends, but each with the determination henceforth to pursue its own economic and political way. This event was profound in its significance and perhaps will be calamitous) in its consequences. Following the disruption of the Conference at Paris, the French immediately began preparations to occupy the Ruhr district on the ground that Germany was in default on coal deliveries, without waiting. for Jan. 15, the next due date for reparation payment. This action by the French led to orders being issued by President Harding on Jan. 10 for the withdrawal of the remainder of the American troops on the Rhine. Thus ended the physical participation in. European affairs by the American army, whose vanguard landed in France in June, 1917. The French occupation of the Ruhr Valley, i.e., the great industrial region of western Westphalia, was made with a large military force. The Germans offered no physical resistance, and passed under French control with sullen resentment. The coal miners to a con-siderable extent refused to work and there was more or less disorganization of railway service. Before the end of the month the opinion was expressed that the French occupation was an economic failure and there were reports of French blast furnaces being blown out for lack of coke.

Jan 2, 1923

Jan 1, 1889

By Vernon E. Swanson, Tom G. Ging

Experiments indicate that simple addition of water to mixtures of untreated trona and otherwise insoluble leonardite yields a rich, black, slightly alkaline solution of concentrated humic substances. Prices of both trona from Wyoming and leonardite from South Dakota and Wyoming are very similar-$10-30 per ton. Leonardite is the term commonly given to naturally weathered, oxidized coal that is readily soluble in slightly alkaline water.1 Several tens of thousands of

Jan 1, 1973

By R. W. Nelson

Methods for determining permeability presented by W. D. Kruger3 in a paper entitled "Determining Areal Permeability Distribution by Calculation" have considerable merit. They can be expected to contribute significantly to analysis of flow in heterogeneous systems. Some rather subtle yet important conditions must be met, however, to assure that the computed permeabilities are correct. The conditions which insure a unique permeability distribution may have been overlooked in the method as proposed and presented in the subject paper. The subtlety of the special requirements may permit good agreement between computed and measured pressures in the reservoir; but the computed permeability may still be in error. The general theory and discussion of the requirements for a unique determination of the permeability distribution are presented elsewhere in more detail.7'8 Accordingly, only major features will be presented here in the notation of Kruger. GENERAL DESCRIPTION OF REQUIREMENTS A brief mention of the route to be followed in showing the special requirements may be helpful. The equation to be solved is a quasilinear, first-order, partial differential equation in the unknown permeability. This equation can be solved through an extension of Lagrange's method by reduction to a system of subsidiary ordinary differential equations. Through consideration of the identity of one of the Lagrange subsidiary differential equations with the stream function, a special interrelationship can be shown. The interrelationship has special significance with respect to the boundary condition. If the boundary function satisfies part of the subsidiary differential equation, no unique solution for the permeability distribution exists. In the physical problem this requirement for uniqueness indicates that the permeability measurements used as a boundary condition can not be along a stream tube. The boundary condition must be along a line, or series of lines, which completely traverse the region and pass through every stream tube.

By Sabert Oglesby, Albert L. Thomas

Until recently, probably the best means of sampling airborne dusts has been the impinger method. Dust-laden air is drawn into a sampling tube, and the particulate matters separated from the air and collected in the liquid in the impinger. A sample of the suspension is prepared on a slide and counted through a projection microscope. This method is simple and reliable, but it does suffer drawbacks. Since the collected particles must be counted visually, results of the dust count are taken. This seriously impedes studying the effectiveness of dust inhibitors, such as water sprays, or making adjustments in equipment. Greatest disadvantage of all, however, is the tedious task of counting particles in the sample. With the growing desirability of taking more samples, the effort involved in making these counts is a real factor in the cost of dust control. Finally, it is generally recognized that impinger dust counts can be related to health hazard only for specific kinds of dust and under similar conditions. This is because the rather complex mechanism of dust damage depends so much on size distribution of the dust. Counts determined by impinger samples cover a limited size range that does not necessarily correlate with retention by the lungs and upper respiratory tract.

Jan 3, 1959

By Kichizo Niwa, Toshio Yokokawa, Mitsuo Shimoji, Yoshihiko Watanabe, Satoshi Kado

A LTHOUGH a systematic research on diffusion in liquid metals has not been carried out, partial studies have been developed by various workers in several systems. A few recent papers among them have shown that this line of approach is quite useful for understanding the structure of the liquid state. Furthermore, it has been found in kinetic

Jan 1, 1958

By AIME AIME

WHETHER by the Mohawk Trail, Sound steamer, air plane, railroad or any other route or mode of locomotion, all roads will lead to Boston the week of National Metal Congress, Sept. 21-25. The Institute of Metals and Iron and Steel divisions of the Institute are then to meet jointly at the Hotel Statler, and the American Society for Steel Treating, the American Welding Society, the Society of Automotive Engineers and the Iron and Steel Division of the American Society of Mechanical Engineers present carefully planned programs at their respective sessions. The National Metal Exposition will be held on Commonwealth Pier.

Jan 1, 1931

By W. R. Seyfried

THE -problem of extracting alumina from clay and low-grade bauxites has been the subject of considerable interest for some time. The basic reason, of course, lies in the fact that known reserves of high-grade bauxite are not inexhaustible and that the present commercial process cannot successfully cope with low-grade bauxites or clay. Ultimately it may be necessary to use these poorer raw materials for all commercial operations, An unprecedented demand for aluminum during the war emergency and the constantly threatened shortage of imported bauxite caused the United States Government to take an active role in this problem. Through the National Academy of Sciences, the War Production Board and the Defense Plant Corporation, it investigated processes and finally selected four to be used in the construction and operation of four experimental plants. Each plant was to be designed in such a way as to facilitate its incorporation into a larger commercial plant should the need arise. The Chemical Construction Corporation process, or "Chemico" ammonium sulphate process as it is better known, was one of the four selected. The extensive literature and patents on record before the war generally follow one of two process-types depending upon the extracting reagent used. One group uses an acid reagent, the other an alkali. The Chemico process uses an acid reagent. For those interested in other processes described in literature, there is a short bibliography at the end of this paper, The basic steps of all acid extraction processes are: (I) to make the aluminum silicates acid soluble, (2) to separate the released alumina from impurities and insoluble gangue, and (3) to recover the reaent for re-use. THE PROCESS AS PLANNED In April 1941, a group of chemists and engineers of the Chemical Construction Corp, became interested in the problem of extracting alumina from clays and low-grade bauxites and, under the leadership of Mr. Blakeslee Barnes, Vice President and General Manager of the Company, first drafted a process in July of that year-five months prior to Pearl Harbor. The work continued in our research laboratories and with a small pilot plant, By June 1943, the work had progressed to a point where it was possible to apply for a patent on the process which was U.S. patent 2,405,426, granted August 6, 1946. Immediately prior to the development of the Salem plant, the process was envisaged to be as follows: I. The first step was to make the aluminum silicates acid soluble. It was planned: (a) Clay or low-grade bauxite would be roasted at 700 to 800°C (1292° to 1492°F). (b) The roasted ore would then be leached .with hot aqueous ammonium bisulphate to form a slurry. In this way the

Jan 1, 1948