Search Documents

The Report on the Manufacture of Coke for the year 1880 by J. D. Weeks1 includes an historical account of the early days of coke-making that is very complete and accurate, and but little can be added to it to fully cover the period prior to 1885. The few additional references that have been found follow. The earliest suggestion found about making coke in this country is in a letter from D. M. Randolph to Harry Heth, dated August 22, 1808. Heth was then operating the mines in the Richmond, Virginia coal field and had sent Randolph to England to investigate steam engines for hoisting and pumping and other conditions in the coal industry there. The letter was written in London and said: "I shall explain to you, how, by turning Deep Run fine coal in Coak, to make great profit from what has heretofore been useless. You will do well to ascertain the price and amount of demand for this article throughout the U. States among brewers and manufacturers. I know how also to make every bushel of such fine slaty coal, fetch as much as any of the best grate coal, by turning it into Coak: and that too, after paying all expenses of the process."2 His interest was to use the slack more for domestic purposes than otherwise, probably, although what the interest of brewers would be in coke as fuel does not appear. Nothing ever came of this suggestion, and so far as known, no coal from this field was coked excepting in gas-making. The Plumpsock Iron Works, mentioned by Weeks as having used coke, was advertised for sale in June 1818.3 It was stated that stone coal was the only fuel used at the works, the pit being within 100 yards of the forge. "Three men with a horse and cart are sufficient to raise coke, and haul to the forge all the coal necessary for keeping the works in full operation." The coke, of course, was made in ricks, or heaps, and not in ovens. The first real coke oven in this country was probably built in Connellsville, the coal coming from a mine nearby on Mounts Creek. L. L. Norton operated an iron foundry and was persuaded by his foreman, one Nichols, who came from Durham, England to build a coke oven. The oven was 12 feet square, and the first coke was produced in 1833. Later

Jan 1, 1942

By E. H. Sellards

ON Oct. 9, 1929, a sink formed in the Sour Lake salt dome oil field in Texas, and on Oct. 12 a second smaller sink formed at the north margin of the first. The purpose of this paper is to give such observations as it has been possible to make on the earth movement incident to this subsidence. Sour Lake salt dome is typical of the salt domes of the Gulf Coastal Plain of Texas. Structurally the dome is a plug of salt which rises to within 900 ft. or less of the surface. Above the salt is a cap rock consisting of anhydrite with more or less calcium carbonate. The salt plug, as contoured on the cap rock, is circular in outline with, however, some appreciable irregularities. Overlying the cap rock are relatively uncompacted sediments consisting of sand, clay and gumbo.. At the crest of the dome these deposits are no more than 700 or 800 ft. thick. However, the sides of the dome are steep, and the sediments thicken rapidly away from the crest. The sink formed about 1500 ft. northeast of the crest of the dome where the sediments overlying the cap rock are from 1000 to 1200 ft. thick. The cavity permitting the subsidence was quite certainly either in the cap rock or in the salt below the cap rock, so that the sink was formed by the caving of as much as 1000 or 1200 ft. of earth.

Jan 1, 1930

By J. A. Church

I. Early Furnaces,......423 11. Experiments with the HIgh-Shaft FURnace,..... 426 III. ExperMents wIth the Wide FURnace,..429 IV. ExperEentS with Extreme BOSH,... 43.2 V. Survival of the 56 by 180 IN. Furnace,.434 VI. Recent ExpeEiments,.....436 VII. SUMMary,........438 I. Early Furnaces. Copper blast-furnace construction in America has long recognized a general standard in the rectangular water-jacketed shaft with separate forehearth. The details, however, and especially those relating to shaft dimensions, have had to meet a great variety of conditions, and show no uniformity whatever. Selecting a few of the present day Western plants, we find furnace lengths varying from 12.5 to 87 ft., widths at tuyere level from 42 to 84 in., and heights above tuyeres from 5 ft. 4 in. to 22 ft. 4 in.; and comparing present designs with those of the past, we meet contrasts no less striking. Unlike its transverse section, the length of a furnace has come to depend rather on the size of unit desired than on the requirements of smelting; and if the question of length be ignored, several of the various existing designs can be grouped together on the basis of a common transverse section. This section, having a width at tuyere level of 56 in. and a height above tuyeres of 18 ft., was developed at Great Falls, and the story of its development contains some interesting features. Ground was broken for the Great Falls works in the spring of 1891. About a year later, the concentrator was able to begin operation, followed within the next few months by the Brueckner, reverberatory, and converter departments, and in April, 1893, by the first blast fur-

Jan 1, 1914

J. Chipman (Massachusetts Institute of Technology, Cambridge, Mass.)—The fact that the experimental work has been applied to copper rather than iron and that the paper is presented to the Iron and Steel Division, I regard as rather significant. It shows the unity of metallurgy and the fallacy of trying to cut it up by metals. This result for the solubility of sulphur in molten copper correlates with Professor Schuhmann's finding that the published data on the other side of the copper-sulphur miscibility gap are also in error. I should like to ask the author to say a little bit more about the sulphur capacity of the slag. T. Rosenqvist (author's reply)-—I hope that Dr. Chipman will find the derivation of the expression for sulphur capacity more clearly explained in the printed version of the paper than in the oral discussion at the meeting. I feel that this quantity, which actually is the ratio of two activities, can be measured more easily than the individual activities. Even if the ratio CaO/CaS is chosen as the standard state, the expression can be used for any slag, even for slags completely free of lime, and it represents a way to put the desulphurizing power of all slag constituents into one bag. Some doubt has been expressed as to whether oxygen ions really exist in calcium oxide and in molten slags. From a thermodynamic view point that question is of minor importance. The term oxygen ion activity, or any activity for that matter, is defined rigorously by the equation: activity = exp u/RT, where u is the change in free energy connected with the transfer of one mol of ions from the standard state into the slag. Whatever happens to the ion in the slag is of no concern to the thermodynamicist. Regardless of whether the ion is "free" in the slag or not, or whether it is present in a very small amount, its activity can always be expressed, and for a thermo- dynamic calculation that is all we need. However, ionic activities will only be of some real value if they are simple functions of the slag composition, or can be measured easily. Concerning the real nature of the oxygen in the slag, my feeling is that the oxygen atom has a rather multiplex nature depending on how strongly it is tied by covalent forces or polarized by the other atoms or ions present. The oxides of iron, cobalt, and nickel differ from calcium oxide and blast furnace slags as to the amount of free electrons that can give rise to electronic conductivity. In slags we know that the conductivity is mostly ionic. The fact that reversible emf's can be obtained with oxygen electrodes in certain salt melts, indicates a significant amount of oxygen ions in these melts. But extended work, e.g. polaragraphic studies and measurements of transference number; are needed to obtain quantitative information about the real structure of the slags. D. E. Babcock (Republic Steel Corp., Youngstown, Ohio)—-With reference to the ion, it might be well to remember Dr. Moses Gomberg. All of his life he had no use for the ionization theory and he contributed greatly to the field of chemistry on the assumption there was no such thing as ions. I do not think we have to worry about whether the oxygen is ionic or not. I think one thing specifically should be brought to your attention and this I think is one of the important contributions of Dr. Rosenqvist. He pointed out what we know as oxygen potentials or what is described as oxygen potentials. I have used this concept for a long period of time and I want to state that if this concept is properly applied, it vitiates much of what we have in the literature, or makes our usual ideas regarding oxidation seem primitive. That one thing is more valuable than almost all the rest of the discussion as a fundamental basis on which to build a reasonable in-

Jan 1, 1952

By C. S. Allen

With increased coal production and mechanization of coal mines many transportation problems arise. The main objective is to bring the coal to the tipple or dump it as quickly as possible. Larger and faster haulage locomotives or two locomotives connected in tandem have been adopted to solve the problem. Motor equipment, gears and control systems of locomotives to be placed on these hauls are carefully studied to meet these requirements, by an analysis of motor characteristic curves with the corresponding tractive effort curves, in order to determine the correct load for maximum efficiency and to determine the approximate schedule. Control equipment is usually considered to be the controller and resistance. Sometimes accelerating curves are calculated in order to obtain smooth starting in the least possible time without slipping the wheels. Train control is very important, but why limit this to acceleration ? Deceleratien-or-retardation of the locomotive is a part of the train control and should be given as much consideration as the control for acceleration. Types or Braking Common braking systems for mine locomotives utilize screw-type mechanical brakes, dynamic braking and the air brake. For gathering and haulage locomotives, the srrew-type mechanical brake is regarded as standard. A brake of this kind cannot be applied without much effort and lapse of time. Motormen, like other people, follow the path of least resistance, and therefore have their brakes ready for instant application—which means that the shoes are virtually dragging. Even then, a motorman bucks and plugs the motors to gain time and avoid as much physical effort as possible. "Bucking of motors" consists in turning the reverse cylinder of the controller to parallel position corresponding to the opposite direction of travel while the locomotive is in motion, without applying power from an external source. When this occurs, both motors tend to act as series generators, because the armatures are revolving and there is residual magnetism in the field circuit. Owing to slight differences in motor manufacture, one of these will generate a slightly higher potential and will overcome the generated voltage of the second and tend to drive it as a motor in the reverse Direction.-This action retards the locomotive but is very severe on the segments of the reverse cylinder and on the motor commutators. "Plugging motors" is the application of power to the motors corresponding to the opposite direction of travel. In order to "plug" the motors it is necessary first to "buck,, them (which reverses the connections to the motors) and then to apply power. Theoretically, this should be done only in an emergency, but locomotives in mine service are frequently thus treated., Dynamic braking is retardation of the locomotive by the motors acting as generators, which take no power from the line.

Jan 1, 1942

By C. S. Allen

With increased coal production and mechanization of coal mines many transportation problems arise. The main objective is to bring the coal to the tipple or dump it as quickly as possible. Larger and faster haulage locomotives or two locomotives connected in tandem have been adopted to solve the problem. Motor equipment, gears and control systems of locomotives to be placed on these hauls are carefully studied to meet these requirements, by an analysis of motor characteristic curves with the corresponding tractive effort curves, in order to determine the correct load for maximum efficiency and to determine the approximate schedule. Control equipment is usually considered to be the controller and resistance. Sometimes accelerating curves are calculated in order to obtain smooth starting in the least possible time without slipping the wheels. Train control is very important, but why limit this to acceleration ? Deceleratien-or-retardation of the locomotive is a part of the train control and should be given as much consideration as the control for acceleration. Types or Braking Common braking systems for mine locomotives utilize screw-type mechanical brakes, dynamic braking and the air brake. For gathering and haulage locomotives, the srrew-type mechanical brake is regarded as standard. A brake of this kind cannot be applied without much effort and lapse of time. Motormen, like other people, follow the path of least resistance, and therefore have their brakes ready for instant application—which means that the shoes are virtually dragging. Even then, a motorman bucks and plugs the motors to gain time and avoid as much physical effort as possible. "Bucking of motors" consists in turning the reverse cylinder of the controller to parallel position corresponding to the opposite direction of travel while the locomotive is in motion, without applying power from an external source. When this occurs, both motors tend to act as series generators, because the armatures are revolving and there is residual magnetism in the field circuit. Owing to slight differences in motor manufacture, one of these will generate a slightly higher potential and will overcome the generated voltage of the second and tend to drive it as a motor in the reverse Direction.-This action retards the locomotive but is very severe on the segments of the reverse cylinder and on the motor commutators. "Plugging motors" is the application of power to the motors corresponding to the opposite direction of travel. In order to "plug" the motors it is necessary first to "buck,, them (which reverses the connections to the motors) and then to apply power. Theoretically, this should be done only in an emergency, but locomotives in mine service are frequently thus treated., Dynamic braking is retardation of the locomotive by the motors acting as generators, which take no power from the line.

Jan 1, 1942

By Albert Brokaw

THE so-called ?paraffin dirt" of the Gulf Coast oil fields has been con¬sidered an indication of the possible presence of oil and gas, and not a few wells have been brought in solely on the basis of such evidence. In a sense, it may be empirically justified as evidence of the presence of oil or gas, though it cannot be said to be infallible. If the writer is correctly informed, its association with oil and gas was pointed out by Lee Hager some years ago, and while it is commonly mentioned by geologists and operators in conversation, no discussion seems to have found its way into print. The present interpretation is based on laboratory study rather than on field investigation, and is put forth with the hope of stimulating discussion which shall lead to more complete understanding. The term "paraffin dirt" has been applied to soils with a peculiar texture, which has been described' as "curdy" or "rubbery." When moist, the material breaks much after the fashion of "green" cheese. It is rubbery under compression, but does not resemble rubber in tenacity or cohesion. When dry, the material ranges from hard clods to a horny mass of high tensile strength. The shrinkage in drying is very great, especially in the hornlike matter. The moist material ranges in color from dark brown in the specimens rich in organic matter to grayish in specimens containing more inorganic matter. All of the specimens studied were readily attacked by molds, which in some cases grew in great profusion on the samples. Samples exhibited a rather characteristic "swampy" or "mucky" odor when wet, and a characteristic odor of humic soils when moist.

Jan 4, 1918

By Henry Rawdon

THE structure of wrought iron as usually described by metallographists and workers in metal in general is that of a fairly pure iron. Impurities, if present, are usually considered as being in solid solution in the crystals of the ferrite matrix or as forming part of the ever present "slag streaks." Attention is herein directed to one type of these dissolved impurities; to the detection of such impurities, particularly in low-grade irons, and to their possible influence on the physical properties of the metal. The attention of the Bureau of Standards was first directed to wrought iron of the peculiar and unusual characteristics to be described later, in material which had failed in service and was submitted for test. The examination was extended to other grades of wrought iron, to see whether such features are of common occurrence in this class of material. MICROSTRUCTURE OF WROUGHT IRON Usual Structure The general microstructure of wrought iron is so well known that a detailed description of it here is needless. There is shown in Fig. 2 the structure of a sample of Swedish iron which illustrates well the matrix of ferrite crystals in which are embedded the slag threads so characteristic of the puddling process and the subsequent working of the material. The usual commercial product contains varying amounts of the impurities commonly associated with iron and steel, i.e., manganese, phosphorus, silicon, and sulphur together with small amounts of carbon. Of these, the larger part of the phosphorus and some of the silicon present are held in solid solution in the ferrite while most of the remaining impurities, other than carbon, exist in the inclosures of slag. Aside from the discontinuities introduced by the slag streaks the ferrite matrix has the microstructure and appearance of a pure metal. No definite orientation of the various crystals or grains is apparent; deep etching of the specimens reveals no intracrystalline features (i.e., within the grains) other than those noted in "pure" metals in general (etching pits).

Jan 9, 1917

By W. F. Holbrook, C. E. Wood, E. P. Barrett

The Blast Furnace Studies Section, Metallurgieal Division, Bureau of Mines, has been working for several years on the mechanism of desulphurization of iron and steel by slags. The usual assumption that desulphurization takes place by diffusion of FeS from metal into slag and subsequent reaction of this FeS with CaO to produce CaS has seemed to us inconsistent with a number of experimental results we have obtained. We undertook, for example, to determine the proportion of sulphur in a slag present as FeS. An entirely satisfactory method of doing this has not yet been evolved. The results of extraction with metallic antimony led to an interesting conclusion, however. FeS is readily soluble in metallic antimony, either physically or by chemical reaction. On the other hand, CaS was found to be insoluble. Hence it would appear that by rapid extraction of the slag with antimony we might expect to determine the distribution of sulphur between iron and calcium. The results showed that much of the sulphur was present as FeS. In some instances the extraction of sulphur as FeS was almost quantitative. For example, in a slag containing 3.8 grams Fe and 3.7 grams S, extraction removed 1.18 grams S and 2.12 grams Fe. If all the iron present in the antimony had been FeS, 1.21 grams S would have been extracted. In another slag with 8.6 grams Fe and 0.06 gram S present, 0.14 gram Fe and 0.08 gram S were extracted. This was obviously extraction of sulphur as FeS within the analytical error and showed that FeS was present either in solution or as a dispersion. Attempts to determine the solubility of FeS and CaS in slag by quenching and ultramicroscopic investigation have indicated that the solubility of FeS is very low, and that reactions in the slag are probably not to be considered as homogeneous. A more detailed report on these theoretical considerations will be made at a later date.

Jan 1, 1940

By W. F. Holbrook, C. E. Wood, E. P. Barrett

The Blast Furnace Studies Section, Metallurgieal Division, Bureau of Mines, has been working for several years on the mechanism of desulphurization of iron and steel by slags. The usual assumption that desulphurization takes place by diffusion of FeS from metal into slag and subsequent reaction of this FeS with CaO to produce CaS has seemed to us inconsistent with a number of experimental results we have obtained. We undertook, for example, to determine the proportion of sulphur in a slag present as FeS. An entirely satisfactory method of doing this has not yet been evolved. The results of extraction with metallic antimony led to an interesting conclusion, however. FeS is readily soluble in metallic antimony, either physically or by chemical reaction. On the other hand, CaS was found to be insoluble. Hence it would appear that by rapid extraction of the slag with antimony we might expect to determine the distribution of sulphur between iron and calcium. The results showed that much of the sulphur was present as FeS. In some instances the extraction of sulphur as FeS was almost quantitative. For example, in a slag containing 3.8 grams Fe and 3.7 grams S, extraction removed 1.18 grams S and 2.12 grams Fe. If all the iron present in the antimony had been FeS, 1.21 grams S would have been extracted. In another slag with 8.6 grams Fe and 0.06 gram S present, 0.14 gram Fe and 0.08 gram S were extracted. This was obviously extraction of sulphur as FeS within the analytical error and showed that FeS was present either in solution or as a dispersion. Attempts to determine the solubility of FeS and CaS in slag by quenching and ultramicroscopic investigation have indicated that the solubility of FeS is very low, and that reactions in the slag are probably not to be considered as homogeneous. A more detailed report on these theoretical considerations will be made at a later date.

Jan 1, 1940

By John W. Wagner, Robert K. Willardson

Single crystals of Pbl-xSnXTe have been grown from The melt under liquid B2O3 using the Czochralski technique. The PbTe-SnTe crystals were grown from near-stoichiometric melts and from melts with slight deviations from sloichiometry. Crystal growth rates ranging from 1 mm per hr to 1 cm per hr were employed, the latter being generally used. Several investigations were performed to characterize the single crystals grown In this study. The phase diagram of the PbTe-SnTe system was examined. X-ray analyses verified the single-crystal character of the crystals, and powder pattern lattice parameter determinations showed that Vegard's law was followed within the limits of the experimental error. The as-grown crystals were p-type with apparent carrier concentrations of -8 x 1018 to -8 x 1020 carriers per cu cm. Hall coefficients, resistivities, and carrier mobilities were determined as a function of composition. Dislocations were revealed by an electrolytic etch, and the crystals were found typically to contain 2 to 4 x 105 dislocations per sq cm. Microhardness measurements were performed; no maximum in the Vickers hardness us composition curve was seen. Mass spectrometry was used for impurity analyses, and the crystals were found to contain 1 to 2 x 1017 total p-type impurities per cubic centimeter. Distribution coefficients were calculated for the major impurities which were Na, Mg, Al, Si, Cl, and Zn. RECENTLY interest has been stimulated in the preparation and characterization of many alloys of the binary compound semiconductors. This interest is due primarily to the almost unlimited possibilities of adjusting the semiconducting characteristics of these materials by varying the alloy compositions. One alloy system which has been receiving extensive investigation is the PbTe-SnTe system, since these alloys show promise of being useful as emitters and detectors of electromagnetic radiation in the spectral range of 8 to 14 µ. This paper reports on the growth of PbTe-SnTe single crystals by the Czochralski technique and investigations of the general properties of these crystals. The phase diagram of the PbTe-SnTe system was investigated so that specific alloy compositions could be attained. I) CRYSTAL GROWTH The PbTe-SnTe single crystals were pulled from the melt using the Czochralski technique. Generally, the crystals were grown from near-stoichiometric melts, although special growth runs were made from both lead-rich and tellurium-rich melts. Growth of single crystals from up to 5 pct lead-rich melts presented no problems; however, melts with tellurium in excess of -1 pct caused volatilization problems which generally made crystal growth impossible. All melts were prepared from high-purity materials as follows: 1) lead— 6 N— Cominco (Cominco Products, Inc., Spokane, Wash.); 2) tin—5N—Cominco; and 3) tellurium— 5N+— American Smelting & Refining Co., Plainfield, N.J. No further purification of materials was undertaken in this study. The elements were reacted at -1000°C in a vacuum-sealed silica tube for a few hours, a gentle rocking action being used to ensure thorough reaction. The cast ingots were then transferred to a silica crucible for crystal growth. A schematic diagram of the growth apparatus is shown in Fig. 1. The Vycor tube is sealed at both ends by O-ring flanges so that a vacuum or a positive pressure may be maintained in the growth chamber. The pull rod and crucible may be rotated; all crystals produced in this study were grown with the crucible sta-

Jan 1, 1969

By Donald A. Brobst

The minerals barite (BaSO4) and witherite (BaCO3) are the chief sources of the element barium and its compounds needed for many industrial processes and products. Barite, the principal ore mineral, is found the world over and is abundant and widely distributed throughout the United States.3 Witherite is much less common than barite, though more desirable in many ways as a raw material for the production of barium chemicals. England is the chief producer of witherite. Witherite is not mined in the United States at the present time, but it has been mined with barite from a deposit at El Portal, California. Barite is also called barytes, tiff, cawk, or heavy spar. Ordinarily it is a heavy mineral that crystallizes in the orthorhombic system. It is colorless, white, or gray, and transparent to opaque. In some deposits barite is black, yellow, brown, red, green, or blue because of included impurities. The streak is white and the luster vitreous to resinous or pearly. The specific gravity of pure barite (65.7 pct BaO and 34.3 pct SO3) is calculated to be 4.5, but inclusions and impurities in natural barite may reduce this value considerably. Well-formed crystals are generally tabular and have three cleavages. The barite of many deposits, however, has an uneven fracture and an apparent cleavage caused by separation along planes between successively deposited layers. The hardness is 2.5 to 3.5 on Mohs' scale. Commercially the terms "hard" and "soft" are used to refer to ease of grinding. Barite is relatively insoluble in water and acid, and thus can be used as a chemically inert material. Witherite, the natural carbonate of barium (77.7 pct BaO and 22.3 pct CO2), crystallizes in the orthorhombic system. The fracture is uneven and the luster is vitreous to resinous. The hardness is 3 to 3.5. The specific gravity of the pure mineral is calculated to be 4.29. It is transparent to opaque. The color is ordinarily white, gray, yellow, brown, or green. Geology and Distribution of Deposits Workable deposits of barite are widely distributed throughout the world in many geologic environments in sedimentary, igneous, and metamorphic rocks. Most deposits can be classified into three main types: (1) vein and cavityfilling deposits; (2) bedded deposits; and (3) residual deposits. 1. Vein and cavity-filling deposits are those in which barite and associated minerals occur along faults, gashes, joints, and bedding planes, and in breccia zones and solution channels. They also occur in various collapse and sink structures in limestone. Sharp contacts of the veins and cavity fillings with wall rocks are common. Barite cements fault and collapse breccia by replacement of the matrix or by filling voids. Large-scale replacement of the wall rocks beyond ore-controlling structures is rare. Barite in vein and cavity filling deposits is generally dense, "hard," and white to gray. Associated minerals are fluorite, calcite, ankerite, dolomite, quartz, and many sulfide minerals, especially pyrite, chalcopyrite, galena, and sphalerite. Gold, silver, and rare earth minerals occur with barite in some deposits in the western United States. Barite is also a gangue mineral in metallic ore deposits but production as a byproduct from such deposits will be affected by many economic factors. The host rocks are igneous, sedimentary, and metamorphic rocks of pre-Cambrian to

Jan 1, 1960

By William E. Schoeneck

This paper presents the problem of oil-well abandonment as a group of studies involving the compilation of physical well data, the use of special curves, maps, and interpretative Procedures, in order that operations can be analyzed and means for reducing costs can be effected. Methods for the calculation of the economic limit of production and resultant oil reserves are suggested in order that profitable production may be continued and premature abandonment prevented. INTRODUCTION Purpose Extensive studies have been made and much has been written on the procedures for prospecting, drilling, completion, production and repair of oil wells, but the writer has long felt the need for a study of the procedure that should be followed when considering the abandonment of a well. The production from numerous well bores of a fluid material (a circumstance peculiar to the oil industry) that is continually decreasing in quantity leads to an increasing ratio of operating cost to production. It is for this reason that oil fields are not abandoned as a whole and detailed consideration of each well is required before it can be determined whether more is being expended than will be returned On any well or lease in question. It is the purpose of this paper, therefore, to compile, correlate, and present all matters worthy of consideration in the problem of oil-well abandonment; to suggest interpretative procedures based on such compilations, to the end that reliable estimates of reserves and life may be obtained; to show, as a result of such interpretative procedures, the possibilities for corrective measures conducive to economical production, thereby extending both profitable reserves and length of life. Scope and Approach Compiling data and outlining a study having the complexity of the problem at hand are naturally subject to the personal experiences of one who undertakes the study; however, the chosen approach and grouping of the subject material may be helpful in the consideration of abandonment problems. Consideration has been given to wells that make gas and water incident with the production of oil; but consideration has not been given to either gas wells or condensate-producing wells, for wells of the latter type have sufficient problems to warrant separate investigation. The major subdivisions of this paper-— physical considerations and economic considerations—do not imply that either of these phases can be considered independently, but rather that the two are mutually dependent and are the component parts of an engineering study.

Jan 1, 1946

By William E. Schoeneck

This paper presents the problem of oil-well abandonment as a group of studies involving the compilation of physical well data, the use of special curves, maps, and interpretative Procedures, in order that operations can be analyzed and means for reducing costs can be effected. Methods for the calculation of the economic limit of production and resultant oil reserves are suggested in order that profitable production may be continued and premature abandonment prevented. INTRODUCTION Purpose Extensive studies have been made and much has been written on the procedures for prospecting, drilling, completion, production and repair of oil wells, but the writer has long felt the need for a study of the procedure that should be followed when considering the abandonment of a well. The production from numerous well bores of a fluid material (a circumstance peculiar to the oil industry) that is continually decreasing in quantity leads to an increasing ratio of operating cost to production. It is for this reason that oil fields are not abandoned as a whole and detailed consideration of each well is required before it can be determined whether more is being expended than will be returned On any well or lease in question. It is the purpose of this paper, therefore, to compile, correlate, and present all matters worthy of consideration in the problem of oil-well abandonment; to suggest interpretative procedures based on such compilations, to the end that reliable estimates of reserves and life may be obtained; to show, as a result of such interpretative procedures, the possibilities for corrective measures conducive to economical production, thereby extending both profitable reserves and length of life. Scope and Approach Compiling data and outlining a study having the complexity of the problem at hand are naturally subject to the personal experiences of one who undertakes the study; however, the chosen approach and grouping of the subject material may be helpful in the consideration of abandonment problems. Consideration has been given to wells that make gas and water incident with the production of oil; but consideration has not been given to either gas wells or condensate-producing wells, for wells of the latter type have sufficient problems to warrant separate investigation. The major subdivisions of this paper-— physical considerations and economic considerations—do not imply that either of these phases can be considered independently, but rather that the two are mutually dependent and are the component parts of an engineering study.

Jan 1, 1946

By Kenneth K. Humphreys, Joseph W. Leonard, Robert L. Llewellyn, William F. Lawrence

INTRODUCTION Cleaning fine coal sizes utilizing air currents in machines as the primary separating medium is called dry concentration or pneumatic cleaning. In 1947 approximately 18 million tons (16.38 million mt) of bituminous coal were cleaned by air machines; in 1965, 25.4 million tons (23.1 14 million mt); but in 1975, only 7 million tons (6.37 million mt). Table 11-1 shows the tonnages cleaned of bituminous coal and lignite in the United States by various types of equipment from 1938-1963. Table 11-2 shows only tonnages cleaned by pneumatic methods from 1964-1975. The decrease in tonnage to approximately 7 million tons (6.3 million mt) is due to a higher moisture content in the mined coal and the greater difficulty in cleaning the coal by air. There also was a definite trend to load raw coal at the mines, especially the slack which is the most expensive to clean due to the dewatering and drying requirements. While there have not been any applications of pneumatic cleaning in the anthracite field, its use has not been fully explored. The same is true for lignite and subbituminous coals.

Jan 1, 1979

By L. S. Darken, H. A. Wriedt

THE constitution diagram of the iron-copper system derived by Daniloff' exhibits, at the iron-rich end, phase fields similar to those of the iron-carbon diagram. At 1484° 1094°, and 850°C there are, respectively, a 6-y-L peritectic, a y-E-Lperitectic, and a a-y-E eutectoid. The phase designated E is copper-rich, containing 4 pct Fe or less according to the temperature. The composition of copper-saturated ferrite (a-solid solution) has been determined previously only twice as a function of temperature. By electrical conductivity measurements, Buchholtz and Köster2 found 3.4 pct Cu in ferrite at a eutectoid temperature of 810°C. They represented the composition of saturated ferrite by the equation, log (%Cu) = 4.32-4125 (1/T) Gregg and Daniloff3 reported that Köster later modified his opinion, raising the indicated eutectoid temperature to 833 °C and the copper content of eutectoid ferrite to 3.7 pct. The literature contains several indications4-7 that the work of Köster and his co-workers is not reliable. Norton,8 using an X-ray method, found that 1.4 pct Cu dissolved in ferrite at the approximate eutectoid temperature of 850°C and that the solubility decreased to about 0.3 pct at 700°C. Below 700°C his experimental data show almost no change in solubility. These findings, although inconsistent with the work of Ruer and Goerens4 and of Smith and Palmer,7 have been used generally since their publication. In investigations involving the observation of arrests in temperature during continuous heating or cooling the precise location of the eutectoid temperature has been obscured by a large hysteresis. The more reliable work 579 where the results are not effected by this hysteresis indicates a eutectoid temperature between 840° and 850°C. The foregoing discrepancies, along with a few observations in this Laboratory relating to the precipitation of copper from ferrite, prompted us to rein-vestigate the lower temperature portion of the Fe-Cu system. In this investigation the solubility of copper in ferrite was obtained by the chemical analysis of high-purity iron equilibrated with copper-silver alloys. This method eliminated the necessity for retaining by a quench the physical state of the specimen existing at the equilibration temperature. EXPERIMENTAL The reaction of the iron with the copper alloy was

Jan 1, 1961

By E. S. Leaver

THE presence of soluble base metals in precious-metal ores usually precludes cyanidation as the best method of treatment. The laboratory experiments described in this paper show the possibility of cyanidation of gold-silver ores containing less than 0.5 per cent, of cyanide-soluble copper and the effect of zinc in the cyanide solution. PART I.-COPPER IN CYANIDATION The proposed process of cyanidation of precious-metal ores containing copper is based on the regeneration of about 80 per cent., of the cyanide used in the dissolution of the copper. The method of regeneration involves a combination of the sulfide and the acid precipitation of the copper and silver. The resultant solution is made alkaline with lime, and the gold is precipitated with zinc dust. Solubility of Copper Minerals in Cyanide Solution In order to determine the solubility of copper minerals, including metallic copper, under the usual conditions for cyanidation, experiments were conducted with synthetic ores. Each ore sample was prepared by mixing the particular pure copper mineral with barren sea sand. Both the mineral and sand were ground to pass 100 mesh before they were thoroughly mixed. The percentage of copper in each head sample was determined by direct assay, excepting the metallic copper sample, which was computed on weights before mixing. Table 1 gives the results.

Jan 1, 1929

Jan 1, 1941

Jan 1, 1940

By Kenneth Cottingham

The number of wells completed in Ohio during I940 was about 20 per cent more than during the preceding year, the comparative totals being 1020 and 1228. Of the 1940 completions, 327 were oil wells, 491 gas wells, and 410 dry. The completions for the past five years, divided into oil wells, gas wells, and dry holes, are shown in Table 2. Wells drilled deeper and input wells in water-flood areas are not included in the tabulation. The annual production of oil has decreased steadily in Ohio from the maximum of 23,941,000 bbl. produced in 1896. Table 3 shows the quantities of oil produced in the last five years. In 1940, the total was 3,052,000 bbl., produced by about 25,500 wells. The number of wells and the approximate quantities by grades are shown in Table I. Table i ,—Tabulation by Grade Grade 1 2 Barrels __________________________________________________________________________________________ Pennsylvania ............. . 1,198,000 Lima.................... . 325,000 Corning................... 3,730 1,159,000 Lodi...................... T,040 350,000 Cleveland................. 30 1:1,000 Total................... 25,500 3,052,000 The prices paid for Ohio crude oil in 1940, together with dates of changes in posting, are shown in Table 4. The production of natural gas in 0hio has declined from a maximum of 79,510,032 M cu. ft. in I9I5 S to 36,469,000 M cu. ft. in 1939, the most recent year for which a figure is available. Consumption reached its peak in Ohio in the year 1916, when it was 169,480,01r M cu. ft., declining to 114,720,ooo M CU. ft. in 1939. The produc-tion and consumption of natural gas in Ohio for the past five years are shown in Table 5. TAble 2.—Completions in Ohio during Past Five Years Numbs of Wells Drilled during Year YearI, ] Oil Gas Dry Total 1936............. 263 570 324 1,157 1937............. 317 503 45I 1,271 1938............. 189 433 288 gro 1939............. I70 501 349 1,020 19391940............. 327 491 410 1,228 Total.......... 1,266 2,498 1,822 5,586 Table 6 shows the number of oil wells and the number of gas wells completed by sands during 1940, with the average initial production per well for each sand. Table 7 shows the total number of wells drilled—oil, gas and dry—by sands. Development during 1940 Szth-Trenton.—For several years, considerahle interest has been shown in a horizon lying some 500 to 700 ft. below the top of the Trenton, known to the driller in western Ohio as the "green sand," and in eastern Ohio as the St. Peter. In 1939, ten 'lgreen sand" tests were drilled, all in western Ohio and all dry- In 19401 eight wells were drilled to this horizon, one of which was a small oil well (one barrel) in Men county- Of the remaining seven—all of which were dry-—one in Franklin County, in central Ohio, was drilled to a depth of 2903 ft. .Another was in Medina

Jan 1, 1941