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By Chingyuan Y. Li, C. Y. Hsieh

REALIZING that aluminum will have a great role to play in the coming industrialization of China, Chinese geologists have long been looking about for some aluminum deposits. The possible sources appear to be alunite, the alumina-rich shales, and the bauxite deposits. The locations of deposits are shown in Fig. I. ALUNITE Our attention was first directed to the alunite deposits along the southeastern coast of China. Table I summarizes the reserves now believed to exist in that region. [ ] Other alunite deposits have been found in Kiangpei, Szechuan province; Channing, Liuyang and Hsanshan, Hunnan province; Tsingchow and Chowyuan, Shantung province. No reserve figures are available. HIGH-ALUMINA SHALE Shale high enough in aluminum to serve as a source of that metal has been found in northeastern China (Table 2). [ ] In Manchuria, the Manchuria Light Metals Co., at Antung and Fushun, operating under Japanese control, has been the only active producer of aluminum. It is not known, however, whether the company uses local raw materials or imports ore from elsewhere.* SHANTUNG BAUXITE Bauxite was first recognized in China at Paoshan, Shantung province. Although the reserve is reported to be large (estimated at 271 million tons), the high content of insoluble residue (Si02) and mineral composition (diaspore) are dis-

Jan 1, 1946

By S. C. Termes, R. L. Wilfong

As part of an effort to provide basic data on the fundamental scientific and engineering principles of minerals beneficiation, the Bureau of Mines is conducting research on the flocculation of mineral fines. This paper presents results of studies using cross-linked starches containing carboxyl, diethanolamine, iminodiacetic acid, and xanthate groups to flocculate hematite, goethite, chromite, manganite, pyrolusite, cuprite, and cassiterite fines. The carboxyl and xanthate derivatives flocculated all minerals except cassiterite; the latter was flocculated by only the diethanolamine derivative. The imlnodiacetic acid derivative flocculated hematite, goethite, chromite, cuprite, and pyrolusite fines. Zeta potential measurements were made to help define the reaction mechanism responsible for flocculation. These measurements indicate that electrostatic attraction probably is not involved, except possibly in the case of the diethanolamine derivative. The separation of hematite from quartz by selective flocculation with chelating crosslinked starches under two pH conditions and with two dispersing agents is described. Best recoveries and grades were found when either the carboxyl or xanthate derivatives was added at the natural pH of the pulp in the absence of a dispersing agent.

Jan 1, 1984

By M. Metzger, J. Intrater

IN the large number of important studies on high-purity aluminum (e.g., recrystallization and grain growth, creep, internal friction), it does not seem to have been generally recognized that the iron content, despite its very low figure, has a strong influence on a number of properties. In part, its influence is due to the very low solubility of the Fe-A1 6 phase. For aluminum of about 99.99 pct purity, the iron content may be 0.001 to 0.004 pct. For values in this range, a second phase will be present below 410" to 480 °C. This was determined by extrapolation of a log solubility vs inverse temperature plot of the solid solubility data of Edgar.' One consequence is the inhibition of grain coarsening below the solubility limit. This is shown in Table I, which gives, for three iron contents, the annealing temperature required for the absence of grains smaller than 1/2 mm average diameter together with the minimum temperature for the presence of some grains larger than 2 mm diameter. The specimens were 1/4x 1 1/2-in. strips cut from hard-rolled 1/16-in. sheet supplied by the Aluminum Co. of America.

Jan 1, 1954

By E. L. Kapfer

A preliminary description is made of the field of automation and optimization of the oxygen blast furnace process. The concept of static and dynamic process control is illustrated. After a short general description of all factors concerning the optimization of this process, a learning system is derived which gives better results than models previously used. This learning or self-adaptive control system uses statistical methods with exponential aging of process data and requires derivation of multi-variable functions of the process for which measurements can be made available. The practical application of this new procedure and of additional measuring instruments are discussed, and results obtained in plants using the adaptive control system are described. A survey of European steel plant automation using the Siemens technique is presented.

Jan 1, 1969

By E. J. Bruderlin

A METALLURGICAL process to be economically successful must be carried on under proper conditions of control and equipment. The question of equipment is always of primary importance. In the dis-tillation process for the recovery of zinc by retorting, the retort is the all-important piece of equipment. Each retort in a working block must function as a separate unit. Over-all block efficiency is the result of the ability of the individual retort -to withstand the severe conditions of operation for a maximum period of time. Therefore retort manufacture has been an ever present problem with the operator of a zinc-retort-ing plant. During recent years the zinc-plant operator has been faced with rapid changes in the character of the ores and concentrates. Operating costs have increased as a result of the- introduction of the flotation process and the amount of flotation concentrates to be handled. To counteract increasing costs, the operator has found it necessary continually to attempt heavier loading of retorts, until a 45 to 50-lb. charge per cubic foot of retort space has become common practice. Heavy loading has brought about severe firing conditions, which, in turn, have emphasized the necessity for further improving the quality of the retort. Increasing percentages of detrimental impurities in the retort charges have also added to the operator's difficulties.

Jan 1, 1936

By Nick Barton, Stavros Bandis

The descriptive term "rock mass" encompasses individual block dimensions ranging from centimeters to many tens of meters. Strength and deformability vary both qualitatively and quantitatively as a result of this size range. A key issue is therefore the appropriate size of the test sample. A large body of test data was reviewed to determine the influence of block size on the displacement required to mobilize peak strength. It is shown that the shear strength and shear stiffness reduce with increased block size due to reduced effective joint roughness, and due to reduced asperity strength. Both are a function of the delayed mobilization of roughness with increasing block size. A method of scaling shear strength and shear displacement from laboratory to in situ block sizes is suggested. It is based on the assumption that size effects disappear when the natural block size is exceeded. This simplification appears to be justified over a significant range of block sizes, but is invalidated when shearing along individual joints is replaced by rotational or kink-band deformation, as seen in more heavily jointed rock masses. Recent laboratory tests on model block assemblies illustrate some important effects of block size on deformability and Poisson's ratio.

Jan 1, 1982

By David R. Maneval

At the turn of the century, 90% of the energy output in the United States was generated by coal, and Pennsylvania was the ranking producer of this fuel. With the huge resources of easily accessible coal found by its early settlers, the Commonwealth was the nation's chief powerhouse for nearly 100 years. In 1928 alone, Pennsylvania mined a billion dollars' worth of coal-or enough to fill a train reaching more than twice around the world at the State's latitude. Coal constituted nearly 67% of the freight of Pennsylvania and was responsible for the State's $4-billion iron and steel industry. Pennsylvania was slow to take up its position as the greatest coal-producing state in the union, but the knowledge of its coal assets was not slow in accumulating. In fact, long before the white man arrived, the Indians were aware that many of the hills were underlain by black stones that would burn. But awareness was not enough. The early Pennsylvania settlers confined themselves to the southeastern corner of the State and had little need or concern for resources further inland.

Jan 1, 1971

By Christopher W. Schram, Allan B. Tanner, Frank E. Senftle, George R. Boynton, Philip W. Philbin

Abstract-A borehole sonde wing a 252Cf neutron source and a Ge(Li) gamma-ray detector was field tested in a coal bed in Belmont County, Ohio, to ascertain whether such a device could be useful as a coal-exploration tool. As the sonde was lowered into the borehole, successive spectra were accumulated over short time intervals. The intensities of the capture gamma rays from hydrogen and of decay gamma rays from aluminum were determined simultaneously in each spectrum. A log of the intensities versus depth shows the depth and thickness of the coal bed.

Jan 6, 1978

By H. M. Roche

IN the first section of- this article, published- Feb. 4, the author reviewed the his¬tory of iron ore mining in New Jersey, listed the reserves and possible markets of this ore, and discussed the role of Lake Superior and foreign ores in domestic steel production. This concluding section of the article emphasizes the metal¬lurgical value, future markets and mining coats of Jersey ores. Mr. Roche's thesis is that industry can profit both metallurgically and econom¬ically through a greater use of Jersey ores --that these orebodies are as yet prac¬tically unexploited, and con¬stitute a valuable national re¬serve fully worthy of careful consideration by Mid-West¬ern steel makers.

Jan 1, 1937

By John P. Bingham

GRACE mine and mill, owned by Bethlehem-Cuba Iron Mines Co. and operated by Bethlehem Cornwall Corp., are being developed to produce 9600 tons of 42 ½ pct Fe magnetite ore, to yield 5760 tons per day of agglomerated iron concentrates averaging 65 pct Fe. Located about 14 miles south of Reading, the property is ideally situated in relation to good highways and railroad. Three major steel plants, at Bethlehem, Steelton, and Sparrows Point, Md., are about equidistant from the mine. Discovery of the orebody resulted from an airborne magnetometer survey, completed in 1948, con¬sisting of 7000 lineal miles of flight lines spaced one-fourth of a mile apart and extending from the Delaware River on the east to Gettysburg, Pa., on the west. After examining the magnetic maps, Bethlehem's geologists made limited surface traverses over the Grace mine and Warwick area to check the location, and realtors were engaged to purchase the desired properties over and adjacent to the area showing favorable indication of ore.

Jan 1, 1957

By Michael B. Gross

A numerical study of the vulnerability of unlined tunnels in jointed rock has been performed with the STEALTH computer program, using the CAVS model for jointed rock. CAVS, for Cracking And Void Strain, is a constitutive model that can simulate the initiation/propagation of fractures and the slip along fracture planes in a jointed rock mass. The CAVS model is unique because it represents a spatially oriented approach to rock failure, rather than the traditional invariant formulation, and because the CAVS submodels for slip friction and slip-induced dilatancy are used to represent the weakening influence of joints, rather than applying ad hoc modifications to the elastic moduli of the host rock. The CAVS model, as embedded in the STEALTH computer program, has performed numerical simulations of tunnel collapse at high overstress levels. These calculations show that the ultimate strength of the tunnel depends strongly on the joint properties, and that the results of the calculations are in qualitative agreement with the observed data for collapse of a tunnel in tuff.

Jan 1, 1984

By Chingyuan Y. Li, C. Y. Hsieh

Realizing that aluminum will have a great role to play in the coming industrialization of China, Chinese geologists have long been looking about for some aluminum deposits. The possible sources appear to be alunite, the alumina-rich shales, and the bauxite deposits. The locations of deposits are shown in Fig. I. Alunite Our attention was first directed to the alunite deposits along the southeastern coast of China. Table I summarizes the reserves now believed to exist in that region. Other alunite deposits have been found in Kiangpei, Szechuan province; Charming. Liuyang and Hsanshan, Hunnan province Tsingchow and Chowyuan, Shantung province. No reserve figures are available. High-alumina Shale Shale high enough in aluminum to serve as a source of that metal has been found in northeastern China(Tab1e 2). In Manchuria, the Manchuria Light Metals Co., at Antung and Fushun, operating under Japanese control, has been the only active producer of aluminum. It is not known, however, whether the company uses local raw materials or imports ore from elsewhere.* Shantung Bauxite Bauxite was first recognized in China at Paoshan, Shantung province. Although the reserve is reported to be large (estimated at 271 million tons), the high content of insoluble residue (SiO2) and mineral composition (diaspore) are dis-

Jan 1, 1948

For the year ending February, 1923 PRESIDENT ARTHUR S. DWIGHT, District 0 NEW YORK, N. Y. PAST PRESIDENTS HERBERT HOOVER, District 4 WASHINGTON, D. C. EDWIN LUDLOW, District 0 NEW YORK, N. Y. FIRST VICE-PRESIDENT J. V. W. REYNDERS NEW YORK, N. Y. TREASURER CHARLES F. RAND NEW YORK, N. Y. SECRETARY FREDERICK F. SHARPLESS,. . . . . NEW YORK, N. Y. ASSISTANT SECRETARY PERCY E. BARBOUR NEW YORK, N. Y.

Jan 7, 1922

By R. W. Raymond

I DESIRE to call the attention of the Institute briefly, and by no means in the way of an exhaustive description, to the interesting developments recently made on the east bank of the Hudson River, in the mining of spathic iron ores. The mines to which I refer are those of the Hudson River Spathic Iron Ore Company, situated at Oakhill on Hudson, Columbia County, N. Y., five or six miles from the city of Hudson, and opposite the town of Catskill. The ore occurs in beds, constituting apparently members of the stratified series of rocks on that side of the river, coursing nearly north and south, parallel with the river, and dipping east. The principal out- crops are presented in a range of low hills, about one mile from the river, along the crest, on the western face of which the stratum of spathic ore is more or less exposed. The length of the line in this range, along which, at various openings the ore has been discovered in profitable quantity, is about two miles. To the northward, the hills are somewhat higher, and the stratification may possibly be disturbed, though the rapid examination of the locality which I made in November last did not, include any determination of this

Jan 1, 1876

By Edgar S. Burkhardt

In mining, the process of comminution starts at the pit and ends at the classifiers. The first machine that breaks or comminutes ore is the primary crusher. There are many types of crushers, but the one most commonly used in large tonnage plants is the gyratory so discussion is restricted to this type of machine. See Figure 1. The primary crusher is the most important piece of comminution machinery in the plant because every ton of ore processed by the concentrator must pass through it, as shown in Figure 2. Most plants can operate if a secondary crusher or a mill is shut down, but if the primary crusher stops, the whole concentrator goes down. It is, therefore, important that the machine be able to produce sufficient ore to keep the concentrator running without hesitation. The plant designer first considers the required daily capacity and an estimate of the size of the ore from the pit. To this he adds an availability factor to compensate for delays due to shovels, trucks and rou- [ ] tine maintenance at the crushing station. This factor is based on experience and can be on the order of 75% (1). With these figures, he determines the hourly capacity required of the primary crushing station to keep the concentrator supplied. See Table I.

Jan 1, 1982

By W. F. Laverty

Two recent papers in this journal1,2 contain experimental evidence for an anomaly in the concentration gradient for tracer diffusion. In both papers, the authors suggest that this anomaly is due to a Gibbs' absorption effect. Their hypothesis is that surface active tracer elements tend to remain in or near the surface adsorption layer, thereby altering the diffusion flux and concentration gradient. It is not clear how the anomaly can be explained in terms of an adsorption effect. Surface tension forces act parallel rather than perpendicular to a surface and therefore should affect only the rate of spreading of surface active agents tangentially across a surface. Frenkel3 has given a short treatment of surface tension as a driving force for surface diffusion. While the equilibrium concentration of a surface active agent at the surface of a solution is known to be higher than in the bulk, its chemical potential is necessarily the same. It is difficult to see how adsorption can result in an anomaly in the chemical potential gradient, which is the driving force for diffusion. A more detailed explanation by the authors of the adsorption mechanism is in order. A similar anomaly does not seem to arise where

Jan 1, 1970

By A. Springer

Chemists, physicists and others, whose occupations necessitate the use of fine scales, have heretofore regretted their inability to obtain any which would remain uniformly accurate. The difference between the theoretical and the actual results obtained in the ordinary balance (provided the pivot-distances are exact) is mainly due to the frictional resistance between the knifeedges and their bearings. This frictional resistance, although reduced to a minimum in the finest scales when new, constantly increases, thereby decreasing the sensitiveness proportionately. When examined under the microscope, neither the surface of the knife-edge nor that of' its hearings ever appears perfectly smooth. Soft kunife-edges are easily blunted, whereas hard ones are brittle and liable to crumble under the effects of over-load or shock. Prof. Frederick A. Roeder for many years attempted to discover some means by ,which the knife-edge could be replaced with some device free from the above-mentioned objections. His experiments convinced him that a torsion-joint was best suited for that purpose. After he had communicated his conclusion to me, we jointly developed the system to its present form. A torsion-wire had been used for the centre of rotation, prior to Prof. Roeder's invention, but it was found impossible to replace the terminal knife-edges with torsion-joints.

Jan 1, 1884

The third special war meeting of the New York Section was held on Thursday evening, Sept. 27, in joint session with the New York Section of the American Electrochemical Society, in conjunction with the Third National Exposition -of-Chemical Industries, at the Grand Central Palace. The topic for discussion was ferro-alloys, and the supply' of raw materials for their manufacture. After a few introductory remarks by President Philip N. Moore, of the Institute, and President Colin G. Fink of the American Electrochemical Society, Mr. C. S. Newcomb presented his paper on "Chrome Mining and Concentration."

Jan 11, 1917

By Young C. Kim

Abstract-The use of computer models to design the ultimate open pit limits during feasibility studies as well as during long-range mine planning is becoming an enforced Practice in all types of mining, e.g., ferrous, non-ferrous, and coal. As a result, the state of the art in computerized ultimate pit limit design methodologies and associated computing and optimizing techniques has advanced considerably in recent years. Unfortunately, very little has been published to date regarding the preferred ultimate pit limit design philosophy, i.e., optimizing m satisfying, or regarding the modeling approaches being used for different types of orebodies. This paper reviews the current state of the art in various modeling approaches and optimizing techniques that are in use for different types of deposits, through available literatures and personal communications.

Jan 10, 1978

By Arthur W. Rose

Statistical techniques are being widely used in geochemical exploration to answer questions involving sample spacing, analytical and sampling errors, thresholds, data smoothing, and optimum combination of several elements into one measure of favorability. The applications of sampling theory, mean and standard deviation, trend surfaces, moving averages, factor analysis, cluster analysis, discriminant analysis, and regression analysis to these questions are discussed with examples. Although the techniques are very useful as means of handling large amounts of data, they require as much geological and geochemical judgment as any other approach to data interpretation.

Jan 1, 1973