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By D. A. Rice, R. L. Stone

Studies of the possible effect of plant water chemistry on the strength of unfired iron ore pellets apparently have not been reported in the literature. Naturally occurring soluble salts were removed from magnetic concentrate filter cakes obtained from several iron ore concentrators. Laboratory balling tests showed that unfired pellets made from these "clean" filter cakes were 50-100% stronger than the usual unfired pellets containing the salts. The fact that certain chemical additives dissolved in the water used for balling "clean" concentrates decreased the strength of unfired pellets indicates that salts in the plant process water may be responsible for lower strengths. According to chemical analyses of plant process waters at these plants, calcium and magnesium are probably the most detrimental salts in the plant circuits. It is suggested that calcium, magnesium, and other polyvalent cations in the mill process waters ion-exchange for lower-valence cations in the bentonite and thereby destroy the electrostatic-charge bonding in the green pellet. Some practical guidelines are also included for plant balling practices.

Jan 1, 1973

By L. J. Boucher

The beneficiation process at Northampton is described and reasons are given for installing a flotation plant. The economics of running the plant, the difficulties of operation, and subsequent remedial action are discussed.

Jan 3, 1953

By Kalanadh V. S. Sastry, D. W. Fuerstenau

Design and operation of a batch balling drum that can be used easily for experimental investigation of the balling or granulation behavior of particulate materials are described briefly. An experimental procedure for ascertaining the growth kinetics of iron ore concentrates or other particulate materials with this kind of apparatus is outlined.

Jan 1, 1972

By Joseph E. Pogue

New economic forces are at work in the petroleum industry. In order to visualize these forces and to see clearly their bearing upon the producer, refiner, and marketer, it is necessary, first, to go back and gain a perspective of the economic evolution of the business. Early Trend to Integration For several decades prior to 1911, the outstanding feature of the petroleum industry was a trend toward integration, culminating in a huge combine, the Standard Oil Co. An important aspect of this integrative trend, however, was its concentration upon a combination and control of refining and marketing, leaving crude oil production, for the most part, to the exigencies of small-unit competition. It is a noteworthy coincidence that during this era the law of oil and gas was formulated and applied, whereby these substances had to be reduced to possession to establish ownership; and the forces of competition in crude oil production were thereby intensified. It was to the interest of an industry, safeguarded in its control of manufacturing and markets, to have supply stimulated by legal convention as well as by individual initiative in order that the growing demand could be met without interruption. And so overproduction of crude oil during this era was no handicap, but rather an aid, to the progress of the industry. Disintegration But the idea of superintegration, despite its efficiencies, became repugnant to the temper of the times and so the Standard Oil Co. was dissolved by Court decree—disintegrated into over 30 parts. And thus, in 1911, was ushered in the second era of the petroleum industry, a period of intense competition. This era coincided with the development of automotive transportation, and a tremendous growth resulted in the effort to keep pace with the mounting demand for gasoline. An intense individualism and unbridled competition were appropriate to this period of entry

Jan 1, 1930

By H. T. Van Ells

The following is a brief description of the cost accounts in effect at the mines of the Anaconda Copper Mining Co. The accompanying chart, Table I., shows the distribution of labor, materials, and redistributable accounts to the various operating and repair accounts. OperatiNG. Development. Owing to the fact that every mine has its peculiarities in formation and methods, the question of arriving at what charges should be included under the head of " Development" is one that has occasioned considerable thought and comment, and in the cost sheet of the Anaconda Copper Mining Co. this account has been sub-divided to show the expenses of breaking ground, tramming, timbering, shaft sinking, up-raising, and cutting stations and skip chutes. It has always been the policy of the company to charge the entire cost of this work to operations monthly, whether the mines are producing or not, also the cost of the opening up of new mines; and only surface construction and additions are charged to capital, excepting original machinery installed for operating pumping plants. Explanations of the charges to the various sub-accounts follow : Breaking Ground.—Work performed in driving cross-cuts from the station, or cross-cuts from the drifts, and diamond-drill work, for the purpose of discovering or developing ore bodies. Tramming.—Cost of tramming waste produced by cross-cuts mentioned above. When waste is hoisted to another level to be used for filling, the charge to this account stops at the station, and when hoisted to surface the charge includes tramming from the collar of the shaft to the dump. Timbering.—Cost of timbering the cross-cuts mentioned above includes the cost of handling and framing such timbers, but does not include the wages of station tenders and top carmen.

Jan 1, 1914

By C. F. Chung

This paper will discuss an application of multivariate discriminant analysis to aid in predicting mineral potential from regional geological data and information on mineral deposits, with particular emphasis on the use of the logistic discriminant function. Logistic discriminant analysis is a generalization of standard discriminant analysis in that the discriminant analysis becomes applicable under a much wider class of distributions. As a practical example, the standard multiple discriminant analysis and the logistic discriminant analysis are applied to data from the Bathurst area in the Appalachian region of Canada and the results are compared with one another.

Jan 1, 1977

By B. M. Andreas

PRIOR to 1934 all haulage of ore and stripping on the Mesabi Range was by rail. Early rail systems had small narrow-gage locomotives with correspondingly small dump cars. These trains were replaced with larger standard gage rail systems powered by steam locomotives ranging up to 224 tons in weight, which have in turn been replaced by diesel electric locomotives. Along with this development cars have been increased to 30-cu yd capacity. Improvement of cars includes alloy steel construction for lower over-all weight and use of roller bearings to decrease rolling resistance. Despite all of these developments, the total material hauled by rail on the Mesabi Range has decreased every year. Yet, this is no reason to believe that rail haulage is becoming obsolete. Its adaptation to small mine operation has become impractical, but in large mines where normal railroad grades are possible or where hauls to plants or dumps are long, rail haulage is still one of the most economical methods of transporting large quantities of material.

Jan 1, 1954

By B. Misra, N. Brook

A new method of determining a "Rock Impact Hardness Number" by comminuting cylindrical specimens in a "Syskov" mortar is proposed. The method of finding Protodyakonov Number by the stamp-mill method was first examined, and the effect of initial size of specimen thoroughly investigated. A method of determining the correct number of blows to use in a test is developed and the inaccuracies involved in the original method, which stem from the measurement of a volume of fines, are avoided by using mass measurements. A graph of percentage fines below 50µtm and number of blows is statistically examined to obtain an accurate estimate of the number of blows to produce 25% fines, from regular initial specimens. This number was defined as the "Rock Impact Hardness Number". The effect of specimen size on this strength index was investigated. A comparison was made between this method of determining rock strength, and a 'field' method using irregular specimens.

Jan 1, 1971

By N. B. Davis

I . INTRODUCTION WHILE working with a number of very sticky cracking clays from western Canada the writer became interested in a study of the cause of the excessive plasticity, This led to a review of the rather bulky literature on the subject and the finding that plasticity still remains to be satisfactorily explained. Most of these investigations seem to have been carried on solely from the chemical viewpoint, the geologic aspects having been ignored. In nearly every case, the investigators have worked with the higher-grade clays of low to medium plasticity, such as the kaolins, the excessively plastic ones having generally been neglected, partly because of their limited application, yet the author believes that these are

Jan 2, 1915

By E. Topuz, S. S. Bhamidipati, M. Bartkoski

Air Leakage in underground mines is the most common cause of inefficient distribution of ventilating air. Depending upon various factors, more than one half of the fresh air entering a mine short-circuits to the return airways before reaching the working faces. Consequently, large leakages create an additional demand for increased intake air, which substantially affects the efficiency of a mine system. This paper deals with the identification of the physical variables of air leakages and offers an overview of the methods of measuring leakage.

Jan 1, 1982

By Fenton Scott, Patrick Hannon

Some occurrences of lead-zinc mineralization in Mississippian carbonates of central Nova Scotia are briefly described. The results of geophysical and geochemical prospecting are presented. Because the deposits do not give a positive response to these indirect techniques it is necessary to site exploratory drilling through the development of geological concepts.

Jan 1, 1976

By C. L. Colburn

THE statutory requirements of the States and the district rules are, broadly speaking, similar. There is just enough difference to make it tantalizing. DIFFERENCES IN STATE LEGISLATION GOVERNING THE LOCATION OF MINING CLAIMS Discovery Discovery is the first step in the location of the claim. The provision of the Revised Statutes (2320) is, "No location of a mining claim shall be made until the discovery of the vein or lode within the limits of the claim located." Strictly speaking, discovery may be defined as the finding of ore or metalliferous rock in place in a well-defined vein. This definition was too strict, so discovery extended later to cover such indications of the presence of ore, within rock in place, as would justify an experienced miner in spending his time and money with a reasonable expectation of finding ore in paying quantities. According to Colorado statutes a discovery must show a well-defined crevice; in Arizona, a lode, deposit, or mineral in place; in Montana, a well-defined crevice or valuable deposit; in Nevada, a lode or deposit of mineral in place. It is wrong to require a discovery. An honest prospector, wishing to obey the law, finds himself compelled, in most cases, to evade this point. In Clear Creek district, Colorado, a quartz seam will constitute a discovery; in Butte, a red capping; in Leadville or Ely, it is any place where a man can find a piece of vacant ground big enough upon which to sink a 10-ft. hole. If the vein or deposit outcrops a man can show a discovery, but if it does not outcrop it is foolish to compel him to show one; and this point has been gently side-stepped. Any hole 10 ft. deep now constitutes a discovery. It is no use having laws that the people cannot consistently obey. No sane man will dig unless he expects to find mineral, and he should be protected while digging. He should be required to show that he has mineral ground only when he comes to patent.

Jan 6, 1914

By A. L. Holley

The three principal mines from which the celebrated Salisbury iron ores are obtained are called respectively the "Old Hill," "Davis," and "Chatfield" ore beds, and are situated in the town of Salisbury, Litchfield County, Conn., on the eastern slope of the Tocconuc range of hills.* The Old Hill Ore Bed is a tract of land of 100 acres, originally granted by the General Court in October, 1731, to be laid out by Daniel Bissell of Windsor. It mas Boon after surveyed and located by Ezekiel Ashley and John Pell. The descendants of Ashley are still proprietors in the mine. The supply of ore has been very abundant, and for many years was easily obtained, but latterly the cost of raising has been greatly increased. Up to about 1840 the average yield was estimated to be about 4500 tons per annum. The production has gradually increased until the average yield at present is estimated at 15,000 tons annually. The largest production in any one ymr was about 20,000 tons. The proprietors of this mine were incorporated many years ago under the style of " The Salisbury Ore Bed Proprietors." The Davis Ore Bed, named after an early owner, was originally called Hendricks Ore Bed, and was owned before the organization of the town of Salisbury by Thomas Lamb, one of the first settlers

Jan 1, 1879

By W. P. Lass

(San Francisco Meeting, September, 1015) THE gold precipitate from the zinc-dust presses in the cyanide plant of the Alaska-Treadwell Gold Mining Co.; Treadwell, Alaska, is treated, in the refinery adjoining, by the Tavener or lead-smelting method. About. 3 or 4 tons of this precipitate are produced monthly having a gold assay value of $40,000 to $60,000 per ton. It was formerly the practice to treat the by-products from this process, consisting of 2 tons of slag, 300 lb. of matte, 500 lb. of refinery refuse, flue dust, etc., in a 24-in. water-jacketed blast furnace. This' practice was discontinued in the summer of 1914 by reason of the difficulty of keeping the lead-well open when treating a high-grade lead product; of preventing the loss of gold in the flue dust; and of avoiding injury to the general health of the refinery operators; a plain single-phase electric furnace was substituted for the blast furnace. The furnace was constructed from an old steel acid drum by cutting off the top and introducing a cable, made from strands of bare copper wire, through the bottom and spreading the strands out fan-shaped on the inside of the drum. Powdered graphite, obtained by grinding up old crucibles, mixed with 10 per cent. cement, was tamped wet into the bottom of the drum, around and completely covering the copper wires. The graphite was carried up to the bottom of the furnace, or lead-well, and acted as the lower electrode. The sides were built up of ordinary firebrick forming a melting chamber 14 in. in diameter by 20 in. high.

Jan 7, 1915

By J. P. Witherow

The plant of Messrs. Oliver Brothers and Phillips, the only one in operation until January, 1886, has not been available for any further experiments since those of Mr. R. W. Hunt, described in his paper on the subject, at the Chattanooga meeting. Continuous working has, however, led to important improvements in plant, and furnished valuable results in practice. The difference between the converter and plant of 1884, as illustrated in our Transactions, vol. xiii., p. 759 and following pages, and those of 1885, may be observed in Plates 1. and 11. accompanying this paper. Plate I. gives the elevation and plan, in half-section, of one of our latest 3-ton converters. Plate 11. gives a plan of the general arrangement of a plant adapted to turn out slabs, blooms, and billets for the general market. The letters on Plate I. refer to the following parts :

Jan 1, 1886

By Ralph Wilcox

The diamond drilling of certain characters of unstable rock formation, as, for example, the copper-bearing schists of the Miami district in Arizona, is rendered most difficult by what is known as a caving " of the sides of the drill holes. As this caving is very greatly increased by the action of flowing water, it occurred to me, after experiencing a great deal of difficulty with caving in diamond-drill holes which I was drilling for the Miami Copper Co., that if I could substitute air for water, much of the caving—with resultant difficulties, such as decreased speed of sinking and increased consumption of diamonds—would be overcome. After some experimenting, I found that it was perfectly practicable to substitute air for the water; forcing the air down the hollow rotating rods in the same manner as is done with water, the air passing out around the bit, which is thus cooled, and ascending on the out~ide of the rods to the collar of the hole, carrying the borings in just as satisfactory a manner as had been done by the water, but without the accompanying destruction or caving of the sides of the drill holes such as had been so generally experienced with the water. When water was encountered in the drilling this water was forced up to the collar just as it would have been had water been used in the drilling, but with the correspondingly decreased flow there was relatively less washing or caving of the sides of the drill holes. The only change necessary in the arrangement of the drill is that a cross instead of a tee is used at the collar of the hole. A tightly woven jute bag is attached to one arm of the cross, for collecting and filtering the sample; and when drilling in dry ground a jet of water is attached to the opposite arm of the cross, to collect the dust and wash down the sample into the bag. The rods rotate through a stuffing box attached to the upper opening of the cross. The distention of the jute bag by the issuing air indicates the operating conditions as sufficiently as did the flow of water when using water in the drill hole. The small percentage of core recovery rendered it necessary to

Jan 1, 1914

By Wei-Kao Lu, G. Bitsianes

An improved general rate equation for a one-ditnensional gas-solid system has been derived. Fov the veversihle interfacial chemical reaction, there are concentrations of gaseous reactant and product at the reacting zone to be considered. They have been calculated with the velations fuvnished by the constraints on the system, namely, quasi-steady state and equimolal counterdiffusion of the gases. The results of the diffusiori study of Evans, Watson, and ,Mason based on the "dusty gas" model have been applied here. The interfacial chemical reaction is taken as first-order with respect to the concentration of the gases involved. The equation has proper dependence on gas composition and on solid structure through the relative values of Knudsen and normal diffusivities. The existence of the total pressure gradient inside the specimen has been predicted and confirmed experimentally. In a previous communication' we introduced a general rate equation for gas-solid reactions by considering the contributions of chemical reaction at inter- phase boundaries and diffusion through the solid product layer simultaneously. These equations, for one-dimensional and spherical specimens, take care of the whole range continuously from purely diffusion control to purely chemical reaction control. In this paper we study only the one-dimensional system. The corresponding rate equation is reproduced here: Of the two terms on the right-hand side of Eq. [I], the first represents the contribution of interfacial chemical reaction and the second that of gaseous diffusion. The shortcomings of Eq. [I] are that in its derivation the interfacial chemical reaction was assumed to be irreversible and the diffusion rate of gaseous product was not considered. Any pressure effects building up within the porous media were also neglected. Evidently. these simplifying assumptions will limit the general applicability of these equations. The rate of reduction of iron oxide by hydrogen, for instance, is very sensitive to the concentration of water vapor in the main gas stream, as has been reported by cewan' and by Quets et a1.3 Furthermore, the gaseous phase at the reacting interface will contain an appreciable amount of the gaseous product of reaction. If this were not true, a sufficiently high concentration gradient for the outward diffusion of the gaseous product could not be maintained. With these shortcomings in mind, Eq. [1I cannot be rigorously ap-

Jan 1, 1967

By W. D. Grundy, Frances Wahl Pierce, Jean-Paul Marbeau, Carol Waite Conner

Resource and coal quality estimates of three coal deposits in the Western United States were estimated by kriging, a geostatistical method that yields unbiased estimates with maximum achievable precision. Derived geostatistical models were used in kriging to estimate the tonnages of the deposits and to derive contour maps of thickness, structure, and sulfur content. Where data were available on quarter-mile spacing, kriging was used to obtain detailed information applicable to mine planning and design. Where data were sparse, kriging was used to do a preliminary evaluation of total resources. Geologic studies were required to correlate the individual coal beds and to identify complicating conditions such as the presence of faults, burnt zones, channels, and regional changes in thickness and elevation. Where these conditions were identified, they were explicitly integrated into the estimation procedure.

Jan 1, 1983

By Bernard Greifer, Walter Rose

The purpose of this note is to call attention to a source of difficulty which can be responsible for inaccurate estimates of wetting liquid pressure gradients in mixture flow experiments of the Hassler1 type. It has been our experience occasionally to observe what were indicated to be negative pressure gradients, and these were regarded as anomalous in the sense that physically they seemed to contradict the requirement that the flux be in the direction of the potential field. At first it was thought that our scheme of assembling barriers and core sample led to such asymmetry in the distribution of isobars that the manometric leads at each end of the core were responding to internal pressures (within the core sample) which could be either positive or negative with respect to each other, and which in fact might tend to reflect on different effective core lengths in an unpredictable fashion as the wetting liquid saturation was changed. However, no compelling evidence of this possibility has been established. In addition, we were cognizant of the requirements to be satisfied in selecting manometric instrumentation to minimize the delay in response of the manometer to the differential pressures being measured, and were thus assured that our observations of anomalous pressure gradients could not be explained by faulty instrumentation. What we suggest is that if a leak sink occurs in the fluid lines connecting the core to either side of the differential manometer, errors exceeding 100 per cent may result in the estimation of wetting liquid pressure gradient, even though the leak is of such small magnitude that its existence would tend to be obscured by evaporation effects. This is because in a system with leaks at the specified places, the manometer rec- ords at steady state the pressure drop across the manometer barrier elements in addition to the pressure drop across the core sample. This possibility will be illustrated below analytically and by numerical example for the special case where the leak occurs on the high presure side of the core, since we are especially desirous to explain the significance of our observations of the so-called negative pressure gradients. It will be indicated, however, that leak sinks on the low pressure side of the core can account for observations of anomalously high values of pressure gradient, and that multiple leaks on both sides of the core can provide for some compensation so that the errors in pressure estimation are reduced. However, the major point to be emphasized is the fact that the impractical-ity of detecting the small leak sinks which give rise to the difficulties makes it a complicated task for the experimenter in a particular case to know with certainty that his estimation of pressure gradient lies within the limits of error which can be tolerated. Fig. 1 shows the electrical analog of the flow system we have employed in our studies. The inflow and outflow barriers. Rbl and Rb2, the manometer barriers, Rm1, and Rm2, and the core sample, Rc— for a particular fluid saturation and distribution— are all designated as resistance elements; the flowmeter is designated by an ammeter, A; the pressure source is designated by E; and the manometric device is designated by the voltmeter, V. Included in the circuit are the variable resistances, Rx and Ry, which may be regarded as the leak sinks, and which, in general, can vary in magnitude from zero (i.e., a large hole or shunt in the system) to infinity (i.e., no

Jan 1, 1950

By Edward L. Estabrook

This paper gives a brief account of the geologic and production problems encountered in the Grass Creek oil field, the methods used in their solution, and the beneficial results obtained from the work. The author wishes to acknowledge the assistance received from J. H. Pearson and Miss Ninettta A. Davis in the collection of the data and the preparation of the cross-sections. Permission for its publication was given by the officials of the Midwest Refining Co. and the Ohio Oil Co. The Grass Creek oil field is located in Ts. 98-99 W., R. 46 N., Hot Springs County, Wyo. The productive area includes about 2 1/2 mi. (4 km.) on the apex of a great anticlinal fold occupying more than 150 sq. mi. Fig. 1 shows the structural contours of the field. Oil was dicovered in the field in June, 1914; development proceeded rapidly and production rose to a maximum in 1918. The marketed production has been approximately as follows: Barrels Barrels 1915.................... 94,073.5 1918................... 2,946,774.27 1916................... 1,404,183.97 1919................... 2,000,584.84 1917.................... 2,780,697.51 1920................... 1,485,080.94 About 350 wells, 800 to 1500 ft. (243 to 457 m.) deep, have been drilled to reach the upper oil sands; two companies, the Ohio Oil Co. and the Midwest Refining Co., operate the entire field. The principal producing sands in the field are members of the Frontier Formation, a series of sands and shales occuring in the upper portion of the Colorado Group of the Upper Cretaceous seriee. These Frontier, or "Wall Creek" sands are also productive in the Salt Creek, Big Muddy, and Elk Basin fields and, therefore, are much the most important reservoirs of light oil in Wyoming. At Grass Creek, the sands in the Formation are more numerous than in the other fields and much less uniform in thickness and character. Usually, eight distinct beds are encountered and in some wells twelve sands have been reported. The formation above

Jan 1, 1923