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By Robert E. Snow, Douglas J. Cosler

The application and development of computer models for simulation of transient ground water inflow to underground mines can assist in mine planning and operation as well as environmental impact assessment. Applications include planning for water handling, treatment, and disposal operations based on predicted mine inflow rates, determination of mining impacts on ground water movement and potentiometric surfaces in neighboring aquifers, evaluation of methods for minimizing ground water inflow, and determination of ground water inflow quality. The potential ground water inflow components to a mine consist of direct inflow from an adjacent aquifer and infiltration through intervening geologic formations. The rates of inflow are controlled by the geologic conditions, the potentiometric surface of the aquifer, and the hydrogeologic characteristics of the water-bearing and confining formations. The capabilities and potential use of a computer model for simulation of mine inflow are illustrated through an example problem.

Jan 1, 1983

By A. Blake Caldwell

In 1936 the Ertsberg story began and its development is a classic example of the courage it takes to discover one mining prospect and bring it into production. Truly, the finding and working of this mine is a modern exception to the overwhelming odds every modern prospector must surmount to be successful. Today, it takes lots of time, plenty of money and the tenacity of a bulldog to whip the laws of nature. Ertsberg ("ore mountain" in Dutch) is literally an elliptically shaped plug of magnetite which erosion has exposed for 560 ft above ground level. The deposit has been likened to an ice cream cone with the outcrop the ice cream, which is above ground, and with the cone buried below the surface. Assaying about 2.5% Cu, the 33 million tons of ore also carry 0.025 oz Au and 0.265 oz Ag per ton.

Jan 1, 1970

By Seishiro Hirakawa, Hiroshi Tokunaga, Hironori Nakamura

Two unique processes of reclaiming zinc from various secondary materials were developed and have successfully been operated for years by Mitsui Mining and Smelting Co. These processes were established based on the characteristic and local energy conditions; i.e., (1) at Miike Smelter, located above the largest coal deposit in Japan, a combination of slag fuming and semi-blast furnace (MF)processes takes advantage of using coal and the carbon bearing briquette residue from the vertical retort plant as reducing agents, (2) on the other hand, at Kamioka Smelter, a direct reduction of zinc-bearing lead slag by using electric furnaces is of advantage in view of cheap electric power supply from our own hydraulic power plants. The former also consumes lots of zinc bearing fines and drosses from various steel plants, fabricators and secondary zinc smelters, while the latter, zinc leach residue from its own electrolytic plant

Jan 1, 1976

By H. Engelmann

THE very extensive development of a brown coal formation, in the region of the Rocky Mountains, is well known to all of you. The existence of these coals was known years ago, but they were of no practical importance until within a few years, when the mineral wealth of that country began to be developed and railroads were built. As their qualities became better known, their adaptability to domestic manufacturing and metallurgical purposes was more appreciated. They are still much undervalued, although they are mined at some points on a very extensive scale. A large portion of this coal formation is of cretaceous age, while it appears to extend into the tertiary epoch; but whatever difference there may be in the ages of these coals of different localities, they all have some common characteristics which distinguish them from our Eastern stone coals of the

Jan 1, 1876

By H. Engelmann

The very extensive development of a brown coal formation, in the region of the Rocky Mountains, is well known to all of yon. The existence of these coals was known years ago, but they were of no practical importance until within a few years, when the mineral wealth of that country began to be developed and railroads were built. As their qualities became better known, their adaptability to domestic manufacturing and metallurgical purposes was more appreciated. They are still much undervalued, although they are mined at some points on a very extensive scale. A large portion of this coal formation is of cretaceous age, while it appears to extend into the tertiary epoch; but whatever difference there may be in the ages of these coals of different localities, they all have some common characteristics which distinguish them from our Eastern stone coals of the

By L. L. Karafiath, S. G. Vick, E. A. Nowatzki

Computer analyses of the trafficability of copper mine tailings by four different commercially available BWEs were performed. A mathematical model incorporating the tailings' Coulomb strength parameters and the vehicles' geometry and operational characteristics was used to study the vehicle terrain interaction. The computer output provides the maximum tractive force (net drawbar pull) that each BWE can develop for given tailings conditions without bnngzng about a state of plastic failure in the tailings. Estimates of sinkage are also provided. The theoretical results for the BWEs and tailings studied compare favorably with the operating experience of similar BWEs used for remining gold tailings in South Africa. This lends some confidence to the validity of the mathematical model. The results of such analyses may be wed to evaluate, on a relative basis, which of a number of different machines would perform better than others under given conditions of a tailings deposit.

Jan 1, 1982

By S. S. Hedge, J. C. Ferm, J. T. Berger

The coal procedures described in this paper address the problems building a body of coal data that is accurate, precise, readily available, and easy to manipulate. The system is a set of interactive computer procedures consisting of a) data gathering (core hole and geophysical logs, their location, elevation, etc.) and standardized computer printouts, b) the graphic outputs of coded logs (log strips-scale variable) wing on-line electrostatic plotter, c) determination of seam continuity via relative movements of the log strips on an interactive graphic display terminal, d) calculation of the seam parameters (minable seam thickness, volume of non-coal material in the seam, ash and sulfur content of the raw or prepared product, roof and floor characteristics and other attributes relevant to mining), e) posting of seam parameters wing on-line drum plotter controlled by a microprocessor on-line to the minicomputer (PDP- 11).

Jan 1, 1983

By Robert Poole

On June 20, 1974, delegations representing the governments of 150 nations convened in Caracas, Venezuela. The occasion: the Third United Nations Conference on the Law of the Sea. (As this article goes to press, the conference is still in session-Ed). Of all the many issues to come before the conference, none is of greater long-term consequence than the issue of jurisdiction over the seabed-the "land" at the bottom of the world's oceans. On the agenda, with widespread support from a majority of UN members, is a proposal to declare seabed resources "the common heritage of mankind," under the sole jurisdiction of the United Nations. Any would-be miner of seabed minerals would have to apply to a UN seabed authority for a permit, and would be forced to pay the bulk of his profits to a UN fund to aid the underdeveloped countries.

Jan 9, 1974

Joseph HartshoRnE, Pottstown, Pa.: I have read Professor Akerman's valuable paper with great interest. Few of the present generation of American steel metallurgists are aware of the very important part taken by Swedish engineers in the successful development of the Bessemer proeess, and I am afraid some of the older ones have forgotten it. Certainly, I think, most of us would have said that Terre Noire was the first to introduce the use of metal direct from the blast-furnace. It is very well, therefore, that honor should be given to whom honor is due. I can speak from personal experience upon one part only of Prof. Akerman's paper; namely, the effect of the temperature at which the molten metal is cast upon the quality of the finished steel. In a general way I have, of course, known for a long time that the

Jan 1, 1894

By George B. Clark, John W. Brown, Hemendra N. Kalia, Ronald R. Rollins

A new theory for three dimensional collapse of conical liners shows why the two dimensional theory may offer a good approximation. Shaped charge design parameters and rock target properties were investigated to determine their effects on penetration and breakage. Penetration in dolomite is somewhat similar to that in steel, but copper does not have markedly better penetration capabilities than brass. Several metals, liner thicknesses, cone angles and standoff ranges for each were investigated. Effective standoff is greater for aluminum than more dense metals. Optimum geometry appears to approximate that for metal targets. Resistance to penetrations was greatest for a red granite and dense siliceous rocks, and least for dolomite and porous sandstone. Hardness and compressive strength appear to be two important conventional proper- ties. The first order law does not apply to the rocks tested. Dolomite may be drilled with shaped charges, the holes sprung and round blasted successfully.

Jan 1, 1971

By V. R. Thompson, R. C. Westgren

In a recent paper,1 the solid-solution strengthening of tungsten and tantalum in a portion of the W-T;-MO-C~ alloy system was described. Additions of tantalum and columbium to tungsten led to significant strengthening, and the introduction of dispersions into these alloys was suggested as a means of further increasing strength. Dispersion strengthening of columbium and molybdenum alloys has been studied extensively.2-4 The approach used to dispersion-strengthen molybdenum alloys appeared equally suitable for tungsten alloys, and, therefore, a brief study was undertaken to determine to what extent the introduction of carbide dispersions would strengthen a solid-solution tungsten-base alloy. A base composition of tungsten and 10 to 12 pet Cb was selected; previous work1 had shown that the tensile strength of this solid-solution alloy was 50,000 psi at 3000°F. For the study of the effects of small additions of

Jan 1, 1964

By Hans Rumpf

INTRODUCTION Agglomeration is based on adhesion between particles. Production of agglomerates of specific strength, strain properties, size, porosity and structure necessitates the activation of the adhesive forces. To achieve this, it is important for us to know details of the various systems of adhesion. Reports on the work of our Institute for the investigation of systems of adhesion were published on various occasions. A reference to those publications is made in the following abstract, and the findings previously published are presented only to the extent necessary for a better understanding of more recent test results, or of changed ideas. 1. MECHANISMS OF ADHESION We must distinguish between various "mechanisms of adhesion". By "mechanism of adhesion" we understand the interaction between a particle and a substrate resulting from a clearly definable physical or physico-chemical process resulting in a definite mathematical interrelation- ship between the decisive variables.

Jan 1, 1977

Joseph HartshoRnE, Pottstown, Pa.: I have read Professor Akerman's valuable paper with great interest. Few of the present generation of American steel metallurgists are aware of the very important part taken by Swedish engineers in the successful development of the Bessemer proeess, and I am afraid some of the older ones have forgotten it. Certainly, I think, most of us would have said that Terre Noire was the first to introduce the use of metal direct from the blast-furnace. It is very well, therefore, that honor should be given to whom honor is due. I can speak from personal experience upon one part only of Prof. Akerman's paper; namely, the effect of the temperature at which the molten metal is cast upon the quality of the finished steel. In a general way I have, of course, known for a long time that the

Jan 1, 1894

By W. F. Carew, H. D. Kessler, F. A. Crossley

AS part of a program on phase relationships and transformation processes of titanium alloy systems, the titanium-rich corner of the Ti-Mo-V system has been investigated. This region was surveyed primarily to supply information toward the development of a creep resistant, weldable alloy, with a minimum alloy content, for use in the 425° to 550 °C range. Specifically, the investigation was directed toward the development of a stable ß alloy with less total alloying additions than is found in the Ti-30 pet Mo alloy. A secondary objective was the development of a creep resistant, weldable a-ß alloy for application around 300°C. Molybdenum was selected as primary additive to titanium on the basis of an investigation1 which showed that the Ti-30 pet Mo alloy had promising elevated temperature tensile properties. Furthermore, aging studies1 showed no tendency for this

Jan 1, 1957

By Chester A. Rowland, David M. Kjos

Mineral ore comminution is generally a feed preparation step for subsequent processing stages. Grinding, the fine product phase of comminution, requires a large capital investment and frequently is the area of maximum usage of power and wear resistant materials. Grinding is most frequently done in rotating drums utilizing loose grinding media, lifted by the rotation of the drum, to break the ores in various combinations of impact, attrition and abrasion to produce the specified product. Grinding media can be the ore itself (autogenous grinding - primary and secondary), natural or manufactured non- metallic media (pebble milling) or manufactured metallic media - steel rods, steel or iron balls. This chapter covers rod and ball mills which utilize manufactured metallic grinding media. Fig. 1 shows the cross section of an overflow rod mill, Fig. 2 an overflow ball mill, and Fig. 3 a diaphragm (grate) discharge ball mill.

Jan 1, 1978

By Joseph Singewald

AMONG the genetically interesting iron ores of the United States are those of the St. Francis Mountains near Ironton and Iron Mountain, Missouri. They are specular hematite in porphyry. The Iron Mountain and Shepherd Mountain deposits are generally spoken of as veins and those of Pilot Knob, Cedar Hill, and Russell Mountain as bedded deposits. Iron Mountain has produced nearly 4,000,000 tons of ore and Pilot Knob about 1,500,000 tons. The output of the other three localities has been insignificant. Pilot Knob is no longer worked as an iron mine, but the rock is now being crushed for use as road metal. Iron Mountain has continued as an active producer. In 1927, the property was acquired by the M. A. Hanna Co. and an extensive prospecting and exploration campaign was undertaken, so that the ultimate production of Iron Mountain will doubtless greatly exceed the figures mentioned.

Jan 1, 1929

Albert SauveuR, South Chicago, Ill. (communication to the Secretary): Mr. Howe remarks (nuns., xxiii., 656) that, running through my paper, there is a tacit assumption that there is a constant and known relation between the coarseness of the grain of steel and its quality. The above assumption was not made tacitly. On the contrary, it is based upon the very experiments embodied in my paper. Indeed, most of those experiments were undertaken with that end in view, i.e., to ascertain the existence of such a relation. Mr. Howe calls attention to the fact that of two pieces of manganese-steel, originally from the same bar, the coarser-grained showed the greater strength and ductility. This refers to the fracture of the pieces; whereas, I have considered the micro-structure only, independent of the fracture; and I do not think that a coarse fracture

Jan 1, 1895

By G. E. Goodspeed

THE Cornucopia gold quartz veins form a parallel vein system traversing metamorphic and granodioritic rocks. Field and petrographic evidence suggests that metasomatism has played an important role both in the emplacement of the granodiorite and in the formation of the veins. Structurally the veins appear to be related to the major tectonic features of the Wallowa Mountains and to be narrow shear zones rather than filled fissures. Petrographic studies indicate a complex history of formation starting from initial alteration along fractures or joints followed by recurrent fracturing and a quartz-forming stage, and closing with continued shearing and microbrecciation, which permitted the upward percolation of the later ore- forming solutions. The precipitation of ore minerals from these solutions formed ore shoots. Postmineral effects include the injection of Tertiary basaltic dikes, a slight amount of cross faulting, and some movement along the planes of the veins as well as oxidation.

Jan 1, 1939

By Marcus A. Grossmann

This paper offers for consideration certain somewhat radical modifications in the iron-carbon diagram, these modifications being the result of the presence of notable amounts of alloying elements. When only small amounts of alloys are present, the standard iron-carbon diagram (Fig. 1) can be used with but insignificant changes; when larger amounts of alloys are present, however, it assumes a distinctly altered appearance. No comment is offered for the present except to call attention to the delta area, A4BM, which represents a region of mixtures of austenite and delta iron, just as area A3SP represents mixtures of austenite and alpha iron. Absence of Carbon We may turn at once to the effect of the presence of alloys. It has been found that in the complete absence of carbon, the gamma change will sometimes disappear entirely when sufficient alloying element is

Jan 1, 1927

By Carl Pierce

THE writer of this article has not attempted to write a technical paper; on the contrary, he has tried to express in "steel-plant English," for steel men, a viewpoint drawn from his practice and experience. It is not his thought that it shall be taken as the "last word" in the making of this class of steel, or that good rimming steel cannot be made by any other practice. The paper was written to serve as the basis of a discussion from which it is hoped much benefit may be derived. The paper deals only with rimming steel made by the open-hearth process, and with the lower carbon steels, such as sheet and tin bar, rivet stock, skelp, etc., although good rimming steel as high as 40 to 50 carbon can be made by having good open slags and giving proper attention to working and tapping temperatures.

Jan 2, 1926