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By Joseph H. Allen

Commercial coke is made to-day in the United States chiefly from the Appalachian, the Illinois and the Colorado coal-fields. The measures of the great Appalachian coal-fields furnish by far the largest proportion, only about 1 per cent. coming from those of Illinois and Colorado. This is not due, however, to a corresponding difference in area. The Illinois field covers about 47,000 square miles in Illinois, Southern Indiana and Western Kentucky. The coal is high in both ash and sulphur, and on this account nearly all the attempts which have been made from time to time to coke it have resulted in failure, so far at least as the requirements of ironmasters are concerned. Nevertheless,. I am able to say from a practical knowledge of this field that the physical structure of the coke is perfect, and

Jan 1, 1893

By Walter S. Weeks, Vitaly S. Grishkevich

Considerable difference of opinion seems to exist as to whether the rate of air flow when a fan is placed on a given duct should be determined by the use of static pressure or total pressure characteristics. A little study will show that both methods are correct. Assume that a fan is connected to a duct by an expansion piece as shown in Fig. 1, and that steady flow is established. Considering the atmospheric pressure as zero pressure, let the static head at the outlet of the fan be h and the velocity at this point be vl. The total head at the outlet is then h + „"• The total head at this point must be equal to the total head at the end of the duct plus the losses that have occurred between the two points. Left be the friction loss in the straight duct, s the shock loss in the dif- fuser, and v2 the velocity at the end of the duct. Then ig. 1.—Fan on duct. A curve showing the value of the left-hand side of the equation for different rates of flow is the total pressure characteristic of the fan, while a curve showing the value of the right-hand side is the total pressure characteristic of the duct. If these two curves are plotted on the same chart, the intersection indicates the rate of flow when steady flow is established. We may look at this problem in another way. The static pressure at the outlet of the fan is the static pressure of the fan and it is also the static resistance of the duct from that point to the end. The friction in the straight duct is f. If the duct were the same area as the fan outlet, would be the static resistance of the whole duct system. In the present case, however, this resistance is decreased by the change of velocity head into static head in the expansion piece. If conversion were perfect, the static pressure recovered would be

Jan 1, 1931

By R. T. Um, W. K. Tolley, J. C. Stauter

A hydrometallurgical process for the recovery of lead from sulfide concentrates is presented The process combines the unit operations of selective dry chlormation, brine leaching and fused salt electrolysis as key steps An overview of the chemistry involved in the process 1s discussed as it pertains to overall recovery.

Jan 1, 1981

By H. M. Warrren

IN the past, steam engines were used in practically all cases for driving the machinery, in and about an anthracite breaker, and hence little or no accurate data were available as to the power requirements for starting and operating the individual machines, which make up the complete equipment. It was impossible to segregate the power necessary to drive each individual machine, first, because the equipment was driven in groups, and second, because it was impracticable to obtain graphic, integrated, or instantaneous records of the horsepower used. As a result of these conditions, it was found, when individual electric motors were applied to the various machines, that more accurate and complete data were needed in order to provide motors of the proper power and design for the particular services to be rendered. In order to obtain the desired information, the writers made and collected a number of tests, from time to time, on the individual motor drives in- electrically operated breakers, and as these tests have been of great value, it occurred to them that a paper giving the results might be of service to other engineers interested in similar installations. Table I shows the .results of these tests. All the motors tested were of the three-phase, 60-cycle, 440-volt, induction, squirrel-cage type, except a few, which, on account of size and starting conditions, were of the wound-rotor type. The instruments used in making these tests were: An integrating watt-hour meter, a graphic ammeter, and a graphic voltmeter. These instruments were connected in each motor circuit, and a record of a day's run of 9 hours was obtained from each machine. From these tests, the running light load, the average all-clay load, and the instantaneous peak readings in amperes, volts, and kilowatt input, were obtained. By means of the characteristic curves obtained from these motors at the factory, the power factor, the efficiency, and the horsepower output were calculated for each particular test. Starting tests were made by the brake-arm method, in which the torque in pounds was measured directly on a spring balance.

Jan 2, 1916

The primary purpose of the Institute is to advance the technologic and engineer-. in- arts embraced by it through inter¬change of knowledge. This can best be clone by the presentation and discussion of technical papers by its members. Short " practical papers are especially welcome. An author should always satisfy himself that his material is of a quality that Will be a credit to him and to the Institute. The preparation of a good paper fre¬quently leads to a reorientation of the author's thoughts, and publication con¬tributes much to the professional standing of the author. Members are urged to submit papers presenting the results of their work. Attention to the following sugges¬tions will greatly further the prompt and efficient handling of manuscripts. 1. SUBJECTS: The subject must be within the field of the Institute.

Jan 1, 1943

By S. W. Parr

The extent to which geological carbonization has taken place in the process of coal formation is a fundamental factor in all considerations relating to classification, oxidation, deterioration, spontaneous combus tion, and especially in all considerations relating to destructive distillation having as an objective the production of marketable coke and by-products. Moreovcr, it may be readily shown that a striking relationship exists between the geological decomposition or geological carbonization processes and those artificially produced by heat. This may be well illustrated by bringing again to view some of the charts more commonly mct with 25 years ago, as in Fig. 1.' In this figurc the line of geological decomposition by decay, pressure, etc., because of its relation to the line of carbonization by destructive distillation, becomes of special significance when we attempt to formulate any system of classification which shall be reasonably scientific and at

Jan 1, 1927

By D. J. Carney, J. Chipman, N. J. Grant

G. Derge—With the development of this last weapon, there is not much of a chance for hydrogen. It is certainly a very interesting paper, and it gives us more confidence in sampling liquid steel for hydrogen than we have ever had before. This satisfactory work gives considerable confidence to all of the chilled methods of sampling which should be more or less successful depending upon the degree of chilling obtained. J. T. MacKenzie—How do you handle a nonmagnetic specimen in that device? D. J. Carney (authors' reply)—I left that out in going over the analytical procedure. For the 18-8 steel, what was done was to get some iron wire which was degassed. One turn of wire was made around the sample; it was inserted into the analytical apparatus, and that was enough to allow the magnet to pull the sample and drop it in the furnace. Other methods could be devised for this apparatus to do the same thing. This was just a quick method. C. E. Sims—This method of sampling and analysis is very ingenious, and the results obtained attest to a satisfactory degree of accuracy. It was noted in the paper that the samples are satisfactory only when there is a complete absence of pipe. This should be empha- sized, particularly in view of the fact that they are cut off under water. Some reservations are held in regard to the adequacy of the method of sample storage prior to analysis. Cooling on dry ice undoubtedly slows down the rate of diffusion to a marked degree, and it obviously suffices when the analysis is made within a few hours. All of the samples, except some of high-nickel steels, were analyzed within 12 hr. It is still unknown how long this method would be safe. In the work at Battelle Institute, it was impracticable always to start analysis within 12 hr for various reasons. Some samples did not reach the laboratory for several days, and some were held as long as a month before analysis. During this period, they were held over mercury, and the gas evolved at room temperature was collected and analyzed. It should be mentioned that both the mercury and the container must be kept very clean.

Jan 1, 1951

By J. D. Raulerson, J. M. Williams

This paper presents a comparative evaluation of several system currently being used or proposed for the transport of matrix from an open-pit mine to a large fixed plant. The matrix is a sticky, wet clay to be carried from 8-16 km (3-10 miles) at 910 t/h to 1.8 kt /h (1,008-2,000 stph). The system is complicated by frequent moves of the open-pit mine site and other factors, such as use of the clay component in land reclamation.

Jan 1, 1984

By H. K. van Poollen, H. C. Bixel

A treatment is given of the transient pressure behavior of a well located at the center of a circular region surrounded by a radial discontinuity. On either side of the discontinuity, the values of permeability, viscosity, compressibility and porosity are uniform but may be different from those on the other side of the discontinuity. The results are obtained by solving a pair of finite difference equations. The numerical solution to these equations is obtained using a digital computer. The results are compared with previously published, approximated analytical solutions to the same problem. Solutions, presented graphically, show pressure decline for constant rate fluid production. The range of variables studied include dimensionless time from '0.001 to 100 and storage capacity ratio from 0.001 to 1,000. The well behaves as if it were in an infinite reservoir for dimensionless times less than 0.25. Reservoir properties near the well can be estimated in the usual manner. An overlay technique is used to match an experimental curve with one of the theoretical curves. It is possible to estimate the distance to a discontinuity by substituting the actual time t and the corresponding dimensionless time tD at which a match occurs into the equation a = (0.000264 tk1/tD , µ1 cI)I/2 where kI/ I µI cI is the diffusivity near the well, and may be estimated from data taken at early time. Several buildup curves are computed. These curves show that for early shut-in times, correct values for transmissibility are obtained from conventional analysis. However, erroneous values of static reservoir Pressure are obtained unless data at large shut-in times are taken. INTRODUCTION A mathematical treatment of the transient pressure response of a well located at the center of a region bounded by a circular discontinuity is given. Within a region (Fig. 20) the properties of both the rock and the fluid are considered to be constant on either side of the discontinuity. While these properties are considered constant, they may be different on opposite sides of the discontinuity. A discontinuity of this type could be a fluid-fluid contact or a sudden change in rock characteristics such as thickness, porosity or permeability. Analytical solutions to this problem are available. 1-3 However, they are so involved that they are of little practical use. An approximate solutionl is available but the range of times over which it is valid has not been specified. A numerical solution to a pair of finite difference equations is used to obtain the solution given in this paper. PREVIOUS WORK One of the first solutions to the problem was published by William Hurst.1 Hurst considered unsteady-state flow of fluids through two sands in series with different mobilities in each sand. He used Laplace transforms to obtain a solution for a single well located at the center of the circle enclosing the first of the two sands. In this case, the solution for the pressure change in Region I (Fig. 20) is2

By John A. Wolfe, James A. Niederjohn

Applications of mathematical statistics to the field of exploration are still relatively new. There are two primary reasons why little has been published in this field. First, if one discovers an effective technique for exploration, he does not like to disclose it. Second, the geologist needs to work closely with a mathematical statistician, and the communications barrier between the disciplines is formidable. The authors, one a geologist and the other a statistician, were interested in the economic benefit which appeared to be possible in the inter-disciplinary area they call "geostatistics."

Jan 11, 1962

By K. Aoki, N. Kameda, T. Esaki

The shortage of adequate construction sites and their difficult location has compelled many engineering structures to be planned in old mining areas in Japan. This paper shows, first, the characteristics of the excavated underground environment and next, the necessary preventive measures during construction of surface structures. Where the depth of a mined out area is relatively shallow, there is a tendency of cave-in consequent to surface loadings. The effect of surface loadings is inversely proportional to the depth of goals. Finally, a power plant project is studied as an example.

Jan 1, 1984

By Dwain K. Butler

INTRODUCTION Characterization of a site for the prediction and simulation of dynamic events requires the determination of mechanical properties of the rock at stress/strain levels and rates and at a scale appropriate for the events and critical structures involved. The structures of interest can be on the surface, underground, or designed to impact and penetrate into the site (projectiles). Dynamic events of interest are equally diverse: seismic waves from distance earthquakes or explosions; close-in phenomena associated with earthquakes and explosions; vibrations associated with heavy equipment or machinery; and stress transients associated with impact and penetration. The complexity of site characterization depends on two factors not specifically related to the nature of the site itself: the stress levels generated by the dynamic event and the sophistication of the prediction and simulation techniques. For very high stress levels, such as occur near a nuclear detonation, and for low stress levels, such as occur during seismic wave propagation, site characterization is simplified, and often certain details of the site are not particularly important, such as shear strength variations in the case of very high stress levels. In the intermediate stress range, however, all descriptive relations are non- linear, a complete finite strain constitutive model is required, and all details of the site, such as lithology and fracture distribution, become important. The site characterization must be complete enough to support the most sophisticated prediction and simulation technique that will be applied to the analysis of the dynamic event. The procedures of site characterization are illustrated in this paper by a specific dynamic event, projectile impact and penetration, and a specific site, an outcrop of Dakota Sandstone near San Ysidro, New Mexico. The structure of interest was the projectile itself: nominally, 1.5 m in length, 0.165 m in diameter, 180 kg

Jan 1, 1984

By D. G. Westlake, E. S. Fisher

The habit planes for zirconium hydride precipitation in crystals of a zirconium have been determined at various hydrogen concentrations. The (10 • 0)planes are the predominant habit planes; some (10 • 5) and (10 -1) planes were observed after charging conditions which pevmitted formation of a surface layer of hydride. No platelets zrlere observed parallel to any of the twinning planes. Mechanisms for em-brittlement due to hydride precipitation are discussed. LANGERON and Lehr1 found, in 1956, that zirconium hydride precipitates in zirconium in platelets lying parallel to (10.0) slip planes. In 1960, Kunz and Bibbz reported observing the platelets in three different families of twinning planes, (10.2) {11.1), and {11.2), but never in the slip planes. The present study was undertaken to ascertain the cause of these seemingly contradictory results. EXPERIMENTAL Two specimens of iodide zirconium were used in the experiments. Specimen I was a single crystal, while specimen II contained three grains. Grain growth was accomplished by the technique of Lange-ron and Lehr. Three faces were ground on specimen I; the first was 2 deg from the (00.1) basal plane, a second was 2 deg from the (10.0) prism plane, and a third was 4 deg from the (12.0) plane. One face was ground on specimen II such that the poles of the surfaces of crystals A, B, and C were as shown in Fig. 1. After the faces were ground on 600 grit silicon carbide paper, they were chemically polished by dipping in a solution of 8 parts hydrofluoric acid, 50 parts nitric acid, and 50 parts water. This removed all cold worked metal from the surface. The samples were charged to various levels of hydrogen content by heating in hydrogen gas which had been purified by reaction with uranium powder. The various charging conditions are shown in Table I. Specimen I was heated to the reaction temperature at the indicated hydrogen pressure and allowed to react until essentially all the hydrogen was used up. Then the temperature was raised for homogenization. Specimen II was charged by making periodic addi-

Jan 1, 1962

By C. E. Cannon, R. C. Craze

This paper discusses the results of a study of reservoir pressures in the Gulf Coast area of Texas and Louisiana, showing the general relation of the reservoir pressure to its subsea depth, as well as excessive reservoir pressures that have been encountered. The latter are particularly important in mud-control work, and the data show why it is necessary to use muds having a relatively high density in many of the deeper wells drilled in this area. Only a comparatively few of the wells drilled in the Gulf Coast that have encountered excessive pressures are discussed, but as far as is known those omitted fall within the range of pressure observed by the writers. Measurement of Pressures The following methods were used to determine the values of the original pressures: 1. Estimation of original pressure from subsequent pressure behavior of fields. This method is not precise, and was used only in a few of the older fields in which better methods of obtaining original pressures were not available. Only normal pressures were determined by this method. 2. Measurement of shut-in pressures soon after completion of the first producing well. With one exception, all pressures measured by this method were normal, this well having a pressure slightly higher than normal. 3. Measurements of pressure in connection with drill-stem tests. 4. Estimates from the maximum hydrostatic head of mud that failed to prevent flow from the high-pressure formations into the hole. This method is not exact, tending generally to indicate low pressures. Normal Pressures All pressure measurements available are plotted in Fig. 1, with original pressure at the water-oil contact as abscissa and subsea depth as ordinate. All producing fields fall close to the solid line, which passes through the origin and has a slope of 0.465 lb. per sq. in. per ft. By way of compari-

Jan 1, 1938

By A. A. Beard

ABOUT three years ago, I. L. Dunn, of Marietta, Ohio, found that wells could be cleaned by blowing with compressed air; this method has been used with great success on many wells in the Marietta, Ohio, district, where compressed air is being used to increase production, by forcing oil through the depleted sands. About a year ago, the process was successfully used to clean out wells in the Lenapah pool in Oklahoma, where an air plant had been installed, under the supervision of I. L. Dunn. Wells from 900 to 1000 ft. deep, with 40 ft. of sand and cavings in them, were cleaned out in from two to three days. The use of this process had, so far, been limited to properties using the Smith-Dunn process, where compressed air, under suitable pressure and volume, was available. For other properties, a portable compressor seemed essential; this was built and successfully demonstrated by Mr. Dunn, for the Tidal Oil Co. in September, 1924. The process of cleaning out with air has been described.1 It consists of lowering the tubing into the well, with a shoe or nipple of heavy pipe substituted for the perforated anchor on the bottom. Into the tubing, compressed air is introduced through a rotary swivel hose at the top, or by means of swing connections. The tubing is lowered to the top of the cave to be cleaned out, several barrels of water are put into the hole, and the compressed air is turned on. This blows out the material between the casing and the tubing, the tubing being lowered as the material is removed.

Jan 9, 1925

By M. N. Nabighian, J. R. Odekirk, D. M. Hausen

Preliminary investigations based on the concept of cross-power indicate that quantitative volume percentages of minerals, including quartz, orthoclase, plagioclase, fluorite, and chalcopyrite can be obtained by X-ray diffraction analysis. Pulverized samples are scanned from 4° to 65°, 2e, using a Norelco diffractometer, with the output recorded on a punched tape at 40 intervals per degree, 29. Errors from crystal orientation are minimized by (1) gridded surface packing, (2) sample spinning, and (3) quantitative measurement of all major diffraction peaks. Computer programming enables rapid quantitative evaluation of X-ray diffraction data. Results to date indicate that most minerals analyses can be performed within an accuracy of ±2%. Metallurgical applications include analysis of various flotation concentrates and tailings.

Jan 1, 1973

By Dewitt T. Ring

Lack of reliable detailed production figures for earlier years, together with the loose nomenclature in reference to producing horizons and the application of the term "field" without any definite meaning or restriction, has made it impossible to gather statistical data suitable for the Institute's form. In common with all other producing areas in the United States, Ohio has felt severely the economic ills of the entire industry during the past year. With overproduction, not only of crude but also of refined products, going on throughout the country, the price structure as a direct consequence has weakened on Ohio oils. Valuable crude is being sold at a big loss today because producers arc willing to, and do, sell more than the market can absorb. The axe hangs heavy over the heads of Ohio producers, and will until something constructive is done to keep supply in proportion to demand. This not only applies to Ohio but to the entire industry. Production of Pennsylvania grade in Ohio was under 50 per cent proration, which has been in effect since Oct. 1, 1937. Three price cuts since February have lowered the posted price from $1.70 to $1.18, a 30 per cent reduction; other grades were less drastically reduced. Pipeline storage facilities were limited; many producers were faced with the problem of providing their own storage or the risk of ruining their wells. If they wanted to pull and abandon wells, there was no market for junk equipment. Many employees have been cut to half time and in a number of instances their services entirely dispensed with. Summary of Production and Drilling Both oil and gas production in the state during 1938 showed a definite decline over the previous year. (A table showing production by years from 1876 through 1937 was published in Vol. 127 of the Transactions.) The total production of crude oil in the state for 1938 was 3,357,914 bbl., as compared with 3,654,000 bbl. in 1937, a decrease of 7.1 per cent. At

Jan 1, 1939

By Dewitt T. Ring

Lack of reliable detailed production figures for earlier years, together with the loose nomenclature in reference to producing horizons and the application of the term "field" without any definite meaning or restriction, has made it impossible to gather statistical data suitable for the Institute's form. In common with all other producing areas in the United States, Ohio has felt severely the economic ills of the entire industry during the past year. With overproduction, not only of crude but also of refined products, going on throughout the country, the price structure as a direct consequence has weakened on Ohio oils. Valuable crude is being sold at a big loss today because producers arc willing to, and do, sell more than the market can absorb. The axe hangs heavy over the heads of Ohio producers, and will until something constructive is done to keep supply in proportion to demand. This not only applies to Ohio but to the entire industry. Production of Pennsylvania grade in Ohio was under 50 per cent proration, which has been in effect since Oct. 1, 1937. Three price cuts since February have lowered the posted price from $1.70 to $1.18, a 30 per cent reduction; other grades were less drastically reduced. Pipeline storage facilities were limited; many producers were faced with the problem of providing their own storage or the risk of ruining their wells. If they wanted to pull and abandon wells, there was no market for junk equipment. Many employees have been cut to half time and in a number of instances their services entirely dispensed with. Summary of Production and Drilling Both oil and gas production in the state during 1938 showed a definite decline over the previous year. (A table showing production by years from 1876 through 1937 was published in Vol. 127 of the Transactions.) The total production of crude oil in the state for 1938 was 3,357,914 bbl., as compared with 3,654,000 bbl. in 1937, a decrease of 7.1 per cent. At

Jan 1, 1939

By S. D. Michaelson

[CONTENTS PACE See TP 2377, Min. Tech, May 1948 for discussion of A Technique for Photographing Difficult Subjects through a Petrographic Microscope (TP 2092 by DONALD W. SCOTT, Min. Tech., Nov. 1946. Discussion by HORACE WINCHELL). Metallurgical Efficiency-a Yardstick in Lead-zinc Flotation Metallurgy (TP 2141 by R. A. ....... PALLANCH, Min. Tech:, March 1947. Discussion by S. D. MICHAELSON). I Symposium on Milling Devices and Practices. (TP 2162 by J. F. MYERS and R. J. TOWER, Min. Tech., May 1947. Discussion by HARLOWE HARDINGE). ............ 2 Rod Milling-Plant and Laboratory Data. (TP 2175 by J. F. MYERS, S. D. MICHAELSON and F. C. BOND, Min. Tech., July 1947. Authors' supplement and discussion by HARLOWE .......................... HARDINGE, and B. H. IRWIN) 2 A New Separating Vessel for Sink-float Concentration. (TP 2182 by E. C. BITZER, Min. Tech., May 1947. Discussion by E. H. CRABTREE, JR.) .................. 5] Metallurgical Efficiency-a Yardstick in Lead-zinc Flotation Metallurgy S. D, MICHAELSON*-The method of determining the efficacy of a separation described in this paper, gives the metallurgist a most useful guide for keeping his ship on an even keel When the ore Waves vary from placid seas to high breakers. Now that such a method of evaluating metallurgical efficiency has been developed and proven practical, it Would seem logical to introduce the next, and more final, factor of Economic Efficiency. I choose to define this term as the percentage ratio of net return from milling to the theoretical maximum net return. The actual operating cost subtracted from the actual mill return represents the net actual amount received for the material treated. Experienced operators of most plants Would ordinarily have enough data on hand to estimate a theoretical milling cost per ton, based on labor, power, supplies and maintenance When operating at maximum tonnage With minimum trouble and under ideal ore conditions. When this theoretical estimated cost is subtracted from the theoretical maximum ore return (calculated by Pallanch's method) the resulting figure is the maximum theoretical net amount the mill operator could hope to realize in processing the ore. The percentage ratio of these sums, of actual to theoretical, is the economic efficiency of the operations. This economic efficiency, if determined on the basis of a fixed market price for metal and similarly fixed base rates for labor, power and supplies, Will reflect the effect of changes in milling practice, labor efficiency and equipment condition. When computations made on the basis of actual current rates for labor, power and supplies are compared With similar actual figures for past periods they will show forcefully how energetic our hunt must be to develop man saving controls, more effective metallurgy, and better equipment to maintain profitable operations. Such computations also offer a simple means of determining how much more labor, supplies and power can be put into the mill operation to obtain an increase in metallurgical recovery at a profit.

Jan 1, 1947

By James J. Bean

Although determining and controlling specific gravity of operating medium in a heavy-media plant manually presents no problem, there are advantages to automatic recording and control. The two installations discussed employ the usual method of measurement. Pneumatic control with band control and reset features is used to regulate dilution water and hence specific gravity. Difficulties have been mechanical in nature and associated with obtaining a proper sample and maintaining tight air connections in bubble-tube piping.

Jan 3, 1950