Search Documents

By Charles Bohdanowicz

The accompanying tables' show that in 1936 production of crude oil in Poland decreased very slightly (Tables 1 and 5), by about 1 per cent, and that gas production increased by about 11 per cent. As in preceding years, drilling (Tables 1, 2 and 3) was devoted principally to extension of oil fields in the Jaslo district (fields 1, 5 and 7) and, in a lesser degree, of those in the Stanislaw6w district (field 27). Production of crude oil is being sustained in a large measure by the deepening of old wells; besides a total number of 183 new wells completed (Table 3) about 152 wells were deepened, and in a general way the results of deepening were better than those of new wells drilled. Reserves of "proved land" have not increased as far as crude oil is concerned, but a notable extension of gas fieldsZ was attained in Daszawa (field 25) and in the Roztoki area (field 5). In the sub-carpathian zone gas fields have been proved in the vicinity of Kalusz, Kos6wJ and in the northwestern sector of that zone, between Tarnow and Lezajsk. The gas horizons of Daszawa occur in the Upper Tortonian, those of Kos6w in the Lower Tortonian (Middle Miocene). Exploratory drilling has been performed near Kalusz, and has been commenced near Kos6w and in the Tarn6w area. The Kos6w gas approaches the "wet" type. A possible gas reserve with a volume of 4,000,000,000 cu. m. (141,000,-000,000 cu. ft.) has been calculated, for an area of about 5 sq. km. of the Daszawa field, on the basis of production obtained and of decreases in pressure and their distribution. The fields of Roztoki and Strachocina (No. 12) have not yet supplied sufficient data for a calculation of reserves, which might possibly be estimated at 2,000,000,000 cu, m. (70,000,-000,000 cu. ft.).

Jan 1, 1937

By C. A. Heiland

The following summary is written for the benefit of the practical operator in the nonmetallic field who wishes to know what geophysics has done and may be expected to do in his line of work. His problem is quite different from that of the geophysicist who has operated with various or all methods and has followed the literature, and who is assumed to be familiar with the geologic possibilities and limitations of each method. This article is not written for the latter, although he may be interested in the four or five hitherto unpublished surveys described. To the operator, on the other hand, geophysics is only secondary. His problem is to determine which geophysical method is best suited to his special needs. If he wanted to know, however, which method could be used to locate a certain material of given physical properties, building stone, for instance, he would have to wade through a tremendous amount of geophysical literature, bibliographies and articles, before he could find what he wanted. Therefore, the purpose of this summary is to present the geological problems first and then to discuss the comparative merits of the geophysical methods that can be, or have been, applied. Choice of Geophysical Methods in Oil, Civil and Mining Engineering In the first two of these fields, the geological problems are not nearly so complex as in the metal and nonmetallic mining fields. The selection of the correct geophysical method in these fields is not nearly so difficult for the operator. For oil prospecting, his problems have been discussed exhaustively by E. DeGolyer.(1) † In civil engineering (foundation and ground-water work), the usefulness of electrical methods has been so well established that there is hardly any choice of other methods at present. The situation may be changed in the future with the perfection of the seismic reflection method for shallow depths. In the mining field the operator and often the geophysicist himself finds difficulty in determining which method is best suited for a given

Jan 1, 1934

By G.A. Moore, C. E. Sims

In previous publications of the writers4-7 it has been shown that vacuum extraction of steel can be carried as close to quantitative completion as desired provided the steel is in the austenitic state and sufficiellt time is allowed. For precise work, the method claims preference because the equipmelit for holding and heating the sample can be made simple, and because crucibles, boats, and other unnecessary materials can be eliminated and the blanks thus made very small. It is well known that the evolution rate of hydrogen is smaller just above the trans. formation than immediately below, as would be expected from the increase in solubility when passing into the gamma state. Many attempts have been made to obtain analyses by extraction just below the transition, using times of approxi. mately 2 hr. while it is true that the rate of evolution drops nearly to zero under these conditions, it has repeatedly been shown that the process is incomplete since on raising the temperature into the austenitic range, evolution will be resumed, usually after a, considerable induction period. The low-temperature evolution process appears to be useful in some cases for comparative tests where the residual crror may be more or less constant between samples, For general use, however, there is no guarantee that the error caused by incomplete extraction is constant; hence, the more laborious but more reliable high-temPe'atu'e Process must be used. At high temperature, an original flash evolution, similar to that at lower temperature, is first observed. After not more than an hour, the flash subsides and cvolution settles down to a regular first-order reaction rate for which the half-life* is usually of the order of a few hours for the 5/8-in. diam cylinder at 1050°C. The regular evolution may be followed for whatever period appears justified, after which the residual gas may be estimated as equal to that which was evolved in the last observed half-life period. Tests have shown that the composition of the evolved gas does not vary greatly during the progress of evolution; therefore the residual gas may safely be taken to have the same composition as the portion col-

Jan 1, 1949

By C. E. Sims, G. A. Moore

In previous publications of the writers4-7 it has been shown that vacuum extraction of steel can be carried as close to quantitative completion as desired provided the steel is in the austenitic state and sufficiellt time is allowed. For precise work, the method claims preference because the equipmelit for holding and heating the sample can be made simple, and because crucibles, boats, and other unnecessary materials can be eliminated and the blanks thus made very small. It is well known that the evolution rate of hydrogen is smaller just above the trans. formation than immediately below, as would be expected from the increase in solubility when passing into the gamma state. Many attempts have been made to obtain analyses by extraction just below the transition, using times of approxi. mately 2 hr. while it is true that the rate of evolution drops nearly to zero under these conditions, it has repeatedly been shown that the process is incomplete since on raising the temperature into the austenitic range, evolution will be resumed, usually after a, considerable induction period. The low-temperature evolution process appears to be useful in some cases for comparative tests where the residual crror may be more or less constant between samples, For general use, however, there is no guarantee that the error caused by incomplete extraction is constant; hence, the more laborious but more reliable high-temPe'atu'e Process must be used. At high temperature, an original flash evolution, similar to that at lower temperature, is first observed. After not more than an hour, the flash subsides and cvolution settles down to a regular first-order reaction rate for which the half-life* is usually of the order of a few hours for the 5/8-in. diam cylinder at 1050°C. The regular evolution may be followed for whatever period appears justified, after which the residual gas may be estimated as equal to that which was evolved in the last observed half-life period. Tests have shown that the composition of the evolved gas does not vary greatly during the progress of evolution; therefore the residual gas may safely be taken to have the same composition as the portion col-

Jan 1, 1949

By N. A. Tiner, Saara Asunmaa

The early stages of nucleation of vacuunz-deposited gold coatings on electropolished surfaces of pure nickel and binary alloys of Ni-A1 and Ni-Ti have been studied, employing carefully controlled temperature and vacuum conditions. The preferential nucleation of gold on slip-plane edges on the crystal surfaces gave rise to a very pronounced decoration effect which was used in studying the morphology of the pain boundaries, etch pits, and slip planes on crystal faces. Characteristic surface patterns were observed with local dimensional variations. Most pronounced geometric patterns were ohserved in the pain boundaries of nickel and on the crystal faces of Ni-A1 alloy. The nucleation behauior of gold indicates contamination on the Ni-T1 alloy and the getter properties of titanium are presented as a tentative interpretation for the detected contamination. The markings and imperfections on cleavage surfaces of crystals have long been observed by optical microscopy.1,2 Surface-replica techniques are also used to detect the smallest steps and structural details on crystal surfaces by electron microscopy. Recently, Bassett3-5 and Sella, Conjeaud, and Trillat 6 have shown that, when gold is deposited onto a rocksalt cleavage surface, there is preferential nucleation at steps and slip-plane edges on the crystal surface. This gives rise to a very pronounced decoration effect which is invaluable for revealing the lattice steps on a cleavage surface. According to Bassett,3 gold atoms arriving during vacuum evaporation at the crystal surface have a certain mobility on the surface after arrival, particularly at elevated temperature. If a significant

Jan 1, 1964

By Thomas B. Douglas

INSTRUMENTATION in the process industries can no longer be regarded as a convenience, but rather an absolute necessity. Although many chemical processes must already be conducted with instruments, every properly designed application of automatic process control will improve operation: 1) the product will be more uniform and of higher quality; 2) the manual labor saved will reduce cost; 3) uniformity of flow and uniform control of process will increase production; and 4) surges will be eliminated, making it possible to operate equipment near ultimate capacity at all times. Industrial instruments fall into two general classifications—those that measure and those that measure and control. The cement industry has been using instruments for a number of years, particularly in the burning process, primarily for indicatlng and recording. Automatic process control makes additional use of these instruments, and others, to control variables. Assisted by the instrument manufacturers, engineers at Ideal Cement Co. achieved considerable progress in determining how well the usual recording instruments could be made to control various phases of cement-making. The results of these experiments were used to make the new plant at Houston as wholly automatic as possible. The original Houston plant, built in 1937 by Gulf Portland Cement Co., consisted of only one 8 x 220-ft kiln and the necessary grinding mills and accessory equipment and had a capacity of 900 bbl per day (300,000 bbl annually). Ideal Cement Co. purchased this plant in 1940 and almost immediately started plans to increase its production. In 1941 a 9 x 220-ft kiln was installed and grinding and storage capacity were increased. The growing demand for cement in the Houston area necessitated a third kiln (9 ft 6 in. x 250 ft) in 1947. This brought the plant up to its present capacity of about 1.3 million bbl per year. Calcium silicates in cement are produced in a burning operation at high temperatures from raw mix of argillaceous and calcareous materials that have been crushed, mixed, and ground to a fine powder. The composition of this mixture must be kept consistent within narrow limits. Raw mixing and grinding may be done either wet or dry, but in both instances the materials must be correctly proportioned, finely ground, and thoroughly intermixed before entering the kiln. As the raw mix passes through a long horizontal rotary

Jan 1, 1959

By Walter L. Maxson, Fred C. Bond

THIS paper is a continuation of two earlier papers, l, 2 and presents new data on the grindability of various ores and other materials-the results of several years of intermittent research work on the nature of grinding and interpretation of test results. It is divided into five parts: 1. The tabulated results of several hundred grindability tests on a wide variety of ores. 2. A method of correcting screen analyses and calculating from them the surface and other properties. 3. A description of a new method of measuring the "surface energy" of an ore by pendulum impact tests. 4. Test results. 5. A general discussion of the test results and their application to grinding problems. 1. GRINDABILITY OF VARIOUS ORES This part is a continuation of the paper listed as reference No. 1. The method of testing is described in detail in that paper. The sample to be tested is crushed to all through 6 mesh in rolls set at x6-in. opening in closed circuit with a screen. Of this sample 700 C.C. is ground dry in a laboratory ball mill under constant conditions of mill speed and ball charge in closed circuit with a screen of the desired size at 250 per cent circulating load. The mill is cylindrical, 12 by 12 in., and rotates at 70 r.p.m. It contains a charge of 285 iron balls weighing 20,125 grams and ranging from 1 ½ to ¾ in. in diameter. Each test is continued for a sufficient number of periods to establish equilibrium at 250 per cent circulating load, or until the composition of the circulating load is constant for successive periods. Tests are conducted at the mesh size to which the ore is to be ground in practice, and the results are expressed as the net production in grams of screen undersize per revolution of the mill. This is designated as the

Jan 1, 1938

By Herbert Clark Hoover, Lou Henry Hoover

PREVIOUSLY I have given much information concerning the miners, also I have discussed the choice of localities for mining, for washing sands, and for evaporating waters; further, I described the method of searching for veins. With such matters I was occupied in the second book; now I come to the third book, which is about veins and stringers, and the seams in the rocks1. The term "vein" is sometimes used to indicate canales in the earth, but very often elsewhere by this name I have described that which may be put in vessels2; I now attach a second significance to these words, for by them I mean to designate any mineral substances which the earth keeps hidden within her own deep receptacles.

Jan 1, 1950

By Leslie G. McMillion

A field project to develop and demonstrate a method for alleviating problems of highly mineralized ground water where they occur as isolated zones or pockets in fresh-water aquifers is being conducted in the Ogallala aquifer of eastern New Mexico by the Robert S. Kerr Water Research Center. Removal of contaminated water is by a large-capacity well and the pumped poor-quality water is used locally for secondary recovery of oil. Benefits of the operation are threefold in that the aquifer is being reclaimed for future fresh-water production, contaminated water is being used beneficially, and fresh water which otherwise would have been used for waterflooding is available for other purposes. Ground-water quality in the site has improved markedly after two years of operation. Use of water in the arid and semiarid Southwest has grown so rapidly that demands in many localities far exceed available supplies. In the High Plains region of New Mexico, Oklahoma, and Texas, the only large sources of water are underground reservoirs, being depleted at an alarming rate. In some parts of this region, the aquifers contain pockets of highly mineralized waters; and the mineralized waters in some of them have started spreading in response to the drawdown effects of pumping wells. The aquifers of this region are primarily composed of sand and gravel beds; any cleanup by natural processes will require many tens or even hundreds of years. Most of these pockets of highly mineralized water were caused by oil-field brines seeping downward from earthen disposal pits. Thousands of these pits were in use in the region until only a few years ago when they were prohibited by the oil regulatory agencies of the respective states. The resulting areas of poor quality water are serious enough to warrant much corrective attention. Correction will involve one or more of three approaches: 1) Restrict the pumping of fresh water in the zones where the drawdown of the pumping well will significantly influence the movement of the contaminant. 2) Remove the highly mineralized water entirely from the affected area. 3) Develop and pump the poor-quality water in such a manner that its movement is held in check, even though only a part of the contaminant is actually removed. The principal hurdle to overcome in applying methods 2 or 3 is financing of the operations, since there are very

Jan 1, 1972

By Robert M. Grogan, Gill Montgomery

Fluorspar, the commercial name for fluorite, is a mineral composed of calcium fluoride, CaF,. Its valuable properties are due to its content of fluorine, and it is the principal commercial source of that element. The name is derived from the Latin word "fluere," to flow, because the mineral has a low melting point and is used in metallurgy as a flux. Cryolite is a sodium aluminum fluoride, Na,AlF,. It is a rare mineral which has been found in commercial quantities in only one place in the world, Greenland. Small amounts of it are shipped from stock in that country, and its place in industry has been taken over almost completely by synthetic cryolite. Because of the relative unimportance of cryolite, discussion of it has been relegated to a short section at the end of this chapter, which is principally concerned with fluorspar. History Fluorspar was used for ornamental purposes by the Greeks and Romans, who fashioned such things as vases, drinking cups, and table tops from it. Various peoples including the Chinese and the American Indians carved ornaments and figurines from large crystals. Its usefulness as a flux was known to Agricola (1564), who wrote about it in 1546. Mining began in England about 1775 and at various places in the United States during the period 1820 to 1840. Production became substantial following the development and widespread adoption of the basic open hearth method of making steel, in which fluorspar is used as a flux. After that, production and usage were stimulated by growth in the steel, aluminum, chemical, and ceramic industries and were accelerated by World Wars I and II. Fluorocarbons entered the picture in 193 1 and the use of anhydrous hydrogen fluoride (HF) as a catalyst in the manufacture of alkylate for high octane fuel blends began in 1942. The development of the froth flotation process in the late 1920s, a differential flotation scheme for separating fluorspar from galena, sphalerite, and common gangue minerals in the 1930s, and the application of heavy-media concentrating methods to the treatment of low grade ores in the 1940s were outstanding technological contributions that enabled increased production of fluorspar concentrates. In recent years the development of pelletizing and briquetting processes for making flotation concentrates into gravel-size particles for use in steel furnaces and the development of more efficient and selective flotation schemes for treating crude ores containing abundant dolomite and barite have been major improvements in the industry.

Jan 1, 1975

By M. L. Fuller

IN connection with an investigation in this laboratory on the high-zinc side of the copper-zinc system, it was observed that well developed segre-gate structures of the Widmanstätten type were formed when a secondary phase precipitated from the solid solution of copper in zinc. This paper presents an analysis of the crystallographic relationship between the segregate and the solid solution matrix. The data to be presented are an interesting addition to the literature on segregate structures in that the plane of segregation is one of the less densely populated planes. In agreement with the generalization of C. H. Mathewson and D. W. Smith1 the plane of segregation in the matrix con-tains the direction of closest atomic packing of the lattice. Furthermore, the matrix and the segregate are both hexagonal close-packed, which has not been reported hitherto in the literature.2 The increasing com-mercial importance of zinc alloys containing copper makes this funda-mental study of value to the metallography of zinc alloys.

Jan 1, 1933

By J. L. Lamont, W. Crafts

Studies of the effect of composition of steel on hardenability by Grossmann,' and as-quenched hardness by Field2 and by the authors, have made it possible to predict the results of quenching when the composition and cooling rate are known In order to extend the application of the hardenability calculation to the quenched and tempered condition in which steel is finally used, a survey has been made of the hardness changes caused by tempering. From this study a method has been developed for the prediction of hardness and tensile strength of steel in the tempered condition. The method of calculation was developed from Rockwell C hardness tests on quenched and tempered Jominy specimens and is expressed in Rockwell C hardness units. It is of an additive type in which the degree of softening from as-quenched hardness is estimated. Tem-pred properties may be calculated within about plus or minus 5 Rockwell C hardness or plus or minus 15,000 lb. per sq, in. tensile strength. This degree of accuracy is less than that necessary for the control of heat-treatment, but is adequate for the comparative evaluation and selection of alloy steels. The formula indicates that tempered hardness is primarily dependent on as-quenched hardness and, as in the hardening reaction, the progress of tempering is controlled mainly by the carbon content. Alloys tend to retard softening by a secondary hardening mechanism in which the alloy appears to migrate from ferrite to the carbide phase. The factors for the effects of alloys in tempering vary so much from the effects of alloys in hardening that different steels of equivalent hardenability may, after like heat-treatment, differ considerably in tensile strength. Procedure In developing the method for calculating tempered Rockwell C hardness, simple and complex steels were tested over a range from 0.08 to 0'65 per cent carbon and up to 2.68 per cent manganese, 2.18 silicon, 3.50 chromium, 4.94 nickel, and 1.06 molybdenum. The steels were made as small induction-furnace heats at the Union Carbide and Carbon Research Laboratories, Inc' The accuracy of the method was finally checked on a variety of carbon, low-alloy and high-alloy types of heat-treating steels produced under commercial conditions. The method was based on a study of tempered Jominy bars, and its validity was tested by correlation with the center hardness and tensile strength of oil-quenched and tempered bars from 1/2 to 4 in. in diameter. The method of calculation was derived from the differences in Rockwell C hardness between as-quenched and quenched and tempered Jominy specimens. Prenormalized Jominy hardenability speci-menS quenched from a normal temperature for austenitizatios were used to obtain a range of as-quenched Rockwell C

Jan 1, 1948

By W. Crafts, J. L. Lamont

Studies of the effect of composition of steel on hardenability by Grossmann,' and as-quenched hardness by Field2 and by the authors, have made it possible to predict the results of quenching when the composition and cooling rate are known In order to extend the application of the hardenability calculation to the quenched and tempered condition in which steel is finally used, a survey has been made of the hardness changes caused by tempering. From this study a method has been developed for the prediction of hardness and tensile strength of steel in the tempered condition. The method of calculation was developed from Rockwell C hardness tests on quenched and tempered Jominy specimens and is expressed in Rockwell C hardness units. It is of an additive type in which the degree of softening from as-quenched hardness is estimated. Tem-pred properties may be calculated within about plus or minus 5 Rockwell C hardness or plus or minus 15,000 lb. per sq, in. tensile strength. This degree of accuracy is less than that necessary for the control of heat-treatment, but is adequate for the comparative evaluation and selection of alloy steels. The formula indicates that tempered hardness is primarily dependent on as-quenched hardness and, as in the hardening reaction, the progress of tempering is controlled mainly by the carbon content. Alloys tend to retard softening by a secondary hardening mechanism in which the alloy appears to migrate from ferrite to the carbide phase. The factors for the effects of alloys in tempering vary so much from the effects of alloys in hardening that different steels of equivalent hardenability may, after like heat-treatment, differ considerably in tensile strength. Procedure In developing the method for calculating tempered Rockwell C hardness, simple and complex steels were tested over a range from 0.08 to 0'65 per cent carbon and up to 2.68 per cent manganese, 2.18 silicon, 3.50 chromium, 4.94 nickel, and 1.06 molybdenum. The steels were made as small induction-furnace heats at the Union Carbide and Carbon Research Laboratories, Inc' The accuracy of the method was finally checked on a variety of carbon, low-alloy and high-alloy types of heat-treating steels produced under commercial conditions. The method was based on a study of tempered Jominy bars, and its validity was tested by correlation with the center hardness and tensile strength of oil-quenched and tempered bars from 1/2 to 4 in. in diameter. The method of calculation was derived from the differences in Rockwell C hardness between as-quenched and quenched and tempered Jominy specimens. Prenormalized Jominy hardenability speci-menS quenched from a normal temperature for austenitizatios were used to obtain a range of as-quenched Rockwell C

Jan 1, 1948

By JOHN JERMAIN

In my opinion, the explanation of the fuel-requirements involving the conception of heat available and necessary above a critical temperature, as advanced by Johnson 1 and elaborated by Howe, Raymond and others,2 affords a theoretically correct basis for such an accounting. It is the purpose of this paper to set forth a first crude attempt to construct a formula which shall show quantitatively the relation between the various factors affecting fuel-economy, and afford a means of comparing the enormous amount of data on the fuel-consumption of various blast-furnaces, at various times and under various conditions of operation. I have also applied this formula to a large number. of individual cases, and have, by its means, compared the furnace-practice of several important iron-making districts. II. DERIVATION OF FORMULA FOR FUEL-REQUIREMENTS. The general expression for the fuel-requirements of the blast-furnace, which I believe to be theoretically correct as to form, is as follows Carbon per ton of iron = Heat per ton of iron necessary in hearth above Tc./Heat per pound of carbon available in hearth above Tc. XFactor of rate of driving. +Carbon dissolved by CO2 of flux. +Carbon dissolved incidental to reduction of ore. + Carbon dissolved in pig-iron. (NOTE.-Tc = critical temperature.) Since, according to Johnson's theory, fuel-economy is usually limited by heat available and necessary in the hearth, rather than by the total heat supplied and necessary, we may write Carbon needed in hearth = Hn/Ha in which Hn is the heat per ton of iron necessary in the hearth above some critical temperature, and Ha is the heat per pound of carbon available in the hearth above this same critical tem¬perature. 1 Trans., xxxvi., 454 (1906). 2 Trans, xxxvi., 792 to 798 (1906) ; Trans, xxxvii., 216 to 237 (1907).

May 1, 1911

By E. A. Breitenbach

A computer program has been developed to afford rapid and complete quantitative log analysis for exploration and production decisions. The computation consists of automatic selection of tops and bottoms of porous intervals from the digitized data, and then point-by-point calculations within each selected interval. Nearly all log types can be analyzed. This paper presents the calculation techniques found to be appticable to machine evaluation and gives examples of their use. INTRODUCTION As the quantitative interpretation of well logs entails repetitive use of charts and equations, it is natural that digital computer programs would be written. A Universal Log Interpretation Computer Program (ULICP) has been developed to afiord rapid and complete analysis for exploration and production decisions. Application of this program enables the log analyst to: (I) apply rapid quantitative log analysis for exploration and production decisions on either a field, a well or on a single zone basis; (2) apply concepts of interpretation requiring detailed numerical analysis; (3) analyze all porous intervals on each log, rather than a few selected zones, and complete the analysis in less time than previously required. Computations are reported for every digitized point in each zone; (4) use empirical techniques applicable to a given area as an integral part of the computation; (5) experiment with the empirical coefficients and exponents in the interpretation equations to find the best possible solution; and (6) automatically plot both the original and computed data to scales analogous to the field prints. The primary utility of a log interpretation program stems from its ability to do an overwhelming amount of work with very little man-power. If a calculation procedure or thought process can be formalized to the extent that step-by-step logic can be written, a computer program can be developed that follows this logic. The major question is one of economics. A feasibility study of the costs for such a program indicates that digital processing is economical primarily as a means of increasing the productivity of the log analyst. In effect, the probability of missing productive intervals in any well, because of a lack of time to do detailed calculations, is greatly reduced. The nucleus of ULICP is programmed to compute large sections of a suite of logs by selecting zones automatically and then performing all pertinent computations on a data point by data point basis within each zone.'.' An entire suite of logs can be processed in this manner with very little manual intervention. Sufficient programming logic is available so that each log analyst can request computations pertinent to his area. These requests are made by simple additions or deletions of information on the input header cards. Hence, the log analyst is always in complete control of the computation process. The evaluation of a suite of logs requires pre-editing, digitization, computation, presentation of results and interpretation. Work by the log analyst is reqilired only in pre-editing and interpretation. Thus, he is allowed more time for comprehensive interpretation, rather than calculation. For continuity, the discussion of ULICP is organized sequentially: pre-editing, digitization, computation and presentation of results. DISCUSSION PRE-EDITING The extent of pre-editing prior to computation is dependent on the format of the original data. For analog prints, it requires inspection, correlation and editing of the logs, plus the entering of required data an special forms. For digitized data such as magnetic tape field recordings, only the special forms are necessary. The process for analog prints will be given here. The inspection and correlation process involves the selection of sections for digitization and the correlation of the traces to a common depth. To decrease the cost of digitization, traces that exhibit large variations in shale formations can be redrawn to a non-zero baseline. The next step is to enter all pertinent data on the input header cards. The header cards presently used for ULICP are presented as Figs. 1 through 6. Cards 1, 2, 3 and 4 (Fig. 1) are defined as the Main Header Cards. They describe the particular well for output identification and give basic information. Cards 5 through 15 (Figs. 2 through 6) are defined as the Block Header Cards. As such, they define the log types and the interpretation parameters for the block of data immediately following. Cards 1 through 10 are required for every computer run. Cards 11 through 14 pertain only to nuclear logs. Card 11 is required if any nuclear log is supplied, and cards 12 through 14 are required only when gamma-ray, density or neutron log data, respectively, are supplied. Card 15 (Fig. 6) must be supplied when cross-plot calculations are required. Either two- or three-component

Jan 1, 1967

By H. M. Day, C. H. Mathewson

THE constitution of the system silver-mercury has attracted the attention of many investigators during the last two decades, but since their results are for the most part in poor agreement, there is little need for a review of their individual contributions. It remained for the very careful thermal and microscopic investigation of Murphy' in 1931 to give the constitutional diagram in its present and unquestioned form, which is shown in Fig. 1. He devised methods for taking cooling curves on alloys under high pressures and for the microscopic observation of alloys which contained liquid mercury as a structural constituent at ordinary temperatures. The compositions of the intermediate phases were confirmed and supplemented through X-ray analyses by Preston2 and Stenbeck.3 According to Murphy, at 276° C. silver is able to dissolve 44 to 45 weight per cent of mercury, which may increase at lower temperatures to about 50 per cent. Preston concluded that the saturation boundary occurred at 46 ± 2 per cent at 100° C. From the values reported in the literature, these are the only ones that may be accepted as lying even in. the right region. PREPARATION OF ALLOYS The silver used in the present investigation was supplied by the United States Metals Refining Co. through the courtesy of the Committee on Industrial Uses of Silver and, since a complete spectrographic and chemical analysis was furnished, no attempt was made to purify it or to further establish the impurities present. The analyses reported by the company are shown in Table 1. Milligan4 has found that the magnesium content is probably less than 0.0005 per cent.

Jan 1, 1938

By W. O. Philbrook, K. Natesan

The oxidation kinetics of spherical pellets of zinc sulfide made from Santander concentrates were studied using a thermogravimetric technique. The experiments covered a temperature range-. of 740" to 102O°C, 0-N mixtures varying from 20 to LOO pct O2, and pellet diameters between 0.4 and 1.6 cm. Mathematical models were formulated to Predict the reaction rate on the assumption that a single transport or interface reaction step was rate -controlling. Analysis of the data indicated that the process of oxidation was predominantly controlled by transport through the zinc oxide reaction-Product layer. ROASTING processes, which are reactions between solids and gases, are very important because they are employed in the production of a number of basic metals. These processes are highly complicated, and one needs to consider the transport phenomena of heat and mass between the solids and gases in addition to the kinetics of various chemical reactions involved. Because of such complications there is a lack of knowledge concerning the rate-limiting factors, which may strongly depend on temperature, particle size, gas composition, and solid structure. The oxidation of zinc sulfide, which is of commercial importance in zinc production, falls into this class of reactions. The major goal of this work was to elucidate the roles played by different process variables, such as reaction temperature, gas composition, pellet size, and pellet porosity, on the kinetics of oxidation of single pellets of zinc sulfide. Roasting of zinc sulfide single particles has been a subject of both experimental and theoretical investigations.&apos;-&apos; The reaction is exothermic and may be considered to be irreversible. Such a reaction has been found to proceed in a topochemical manner. In other words, as the reaction proceeds, a progressively thicker outer shell of zinc oxide is formed, while the inner core of unreacted sulfide decreases. It has been found experimentally, both in the present work and in the previous investigations,1-9 that the particle retains its original dimensions and the process requires transport of gaseous oxygen across the porous product layer for continued reaction. The reaction may be represented by ZnS(s) + 3/2 O2(g) = ZnO(s) + SO2(g) [1] The solid product considered here is only zinc oxide, since the diffraction patterns of zinc sulfide pellets oxidized partially at &apos;798" and 960°C showed K. NATESAN, Junior Member AIME, formerly St. Joseph Lead Fellow, Department of Metallurgy and Materials Science, Carnegie-Mellon University, Pittsburgh, Pa., is now at Argonne National Laboratory, Argonne, Ill. W. 0. PHILBROOK, Member AIME, is Professor of Metallurgy and Materials Science, Carnegie-Mellon University. This paper is based on a them submitted by K. NATESAN in partial fulfillment of the requirements for the Ph.D. degree in Metallurgy and Materials Science at Carnegie-Mellon University. Manuscript submitted December 2, 1968. EMD lines corresponding to original zinc sulfide and the newly formed zinc oxide. OXIDATION MODEL The generalized model for gaseous oxidation of zinc sulfide is illustrated in Fig. 1. This depicts a partially oxidized sphere of zinc sulfide in a gas stream surrounded by a laminar film of gas. The spherical sample of zinc sulfide of unchanging external radius r0 is suspended in a flowing gas stream of total pressure PT and composition specified by the partial pressures of the individual components. Partial pressures of the gaseous species in the bulk gas phase, at the exterior surface of the pellet, at the ZnS/ZnO interface, and at equilibrium for Reaction [I] are identified by the superscripts b, o, i, and eq, respectively. The overall reaction involves the following ~te~s:&apos;~&apos;~&apos; Step 1. Transfer of reactant gas (oxygen) from the bulk gas stream across the gas boundary layer to the exterior surface of the pellet and the reverse transfer of the product gas (sulfur dioxide). Step 2. Diffusion and bulk flow of oxygen from the pellet surface through the product shell (ZnO) onto the ZnS/ZnO interface and the reverse transfer of sulfur dioxide. Step 3. Chemical reaction at the interface, which results in consumption of oxygen gas and generation of sulfur dioxide gas and heat; at the same time the _________ PARTICLE SURFACE / x^^^^n^X / MOVING INTERFACE core-----/ sJSNxy " /T^T^02 \ V\V$\ ^NWX/ "*/— GAS BOUNDARY x. \\ZnO SHELLV/ / \^ . / &apos; ^ BULK GAS --------N_______ _____,------p£ w \ P« / (f> \ / a \ <i) / <----------------- _(o) ^^--------------(b) °- pso, pso2 ro ri 0 ri ro RADIAL POSITION Fig. 1—Generalized model for oxidation of a sphere of zinc sulfide.

Jan 1, 1970

By Robert D. Pike

In November 1939, on behalf of the Harbison-Walker Refractories Co., the author undertook the study of the problem of utilizing the dolomite of northwestern Ohio for the manufacture of calcined magnesia suitable for use in refractories. Grateful acknowledgment is made of the unfailing assistance and encouragement throughout this work from the executive and technical staff of Harbison-Walker Refractories Company. The dolomite of the Niagara formation that is exposed or near the surface of a wide area in northwestern Ohio1 constitutes a vast supply of almost pure dolomite. It offers a virtually unlimited supply of cheap raw material of uniform dependable analysis for the manufacture of magnesia. A typical analysis of dolomite from the vicinity of Luckey, Ohio, follows: Stone Completely Calcined CaO(Sro)a............. 30.35 57.806 Mgo................... 21.55 41.050 SiO2. ................... 0.30 0.572 R2O3................... 0.30 0.572 Ignition loss............. 47.50 a SrO about 0.06 pct. Brines containing magnesium chloride or sea water can be reacted with calcined dolomite to produce magnesia.2&apos;3 In such reactions the MgCl2 of the brine supplies some of the magnesia and the amount of dolomite required is thereby reduced by an equivalent amount, but brines of commercial importance containing magnesium chloride are some distance away from the purest grades of the dolomite of northwestern Ohio. It was decided therefore to concentrate upon the development of a suitable process for separating the lime and magnesia of dolomite, depending upon the dolomite itself as the sole source of magnesia. This would make it possible to place a plant at the dolomite quarry, thus eliminating the cost of transporting the stone and also rendering the calcined magnesia available at a most convenient production point, considering the cost of delivery throughout the steel industry. The selection of a process depending solely upon the dolomite as a source of magnesia also necessarily entails production of the lime content of the dolomite as a by-product. It was recognized that if such a lime by-product could be produced in a suitable form, a plant location in northwestern Ohio would also be advantageous for marketing the lime. The problem, therefore, was the discovery and development of a low-cost process for separating the magnesia and lime of the dolomite of northwestern Ohio and producing each in a form relatively free from the other, and meeting the respective requirements of established markets. A satisfactory solution of this problem has been found, and it is the

Jan 1, 1948

By Robert D. Pike

In November 1939, on behalf of the Harbison-Walker Refractories Co., the author undertook the study of the problem of utilizing the dolomite of northwestern Ohio for the manufacture of calcined magnesia suitable for use in refractories. Grateful acknowledgment is made of the unfailing assistance and encouragement throughout this work from the executive and technical staff of Harbison-Walker Refractories Company. The dolomite of the Niagara formation that is exposed or near the surface of a wide area in northwestern Ohio1 constitutes a vast supply of almost pure dolomite. It offers a virtually unlimited supply of cheap raw material of uniform dependable analysis for the manufacture of magnesia. A typical analysis of dolomite from the vicinity of Luckey, Ohio, follows: Stone Completely Calcined CaO(Sro)a............. 30.35 57.806 Mgo................... 21.55 41.050 SiO2. ................... 0.30 0.572 R2O3................... 0.30 0.572 Ignition loss............. 47.50 a SrO about 0.06 pct. Brines containing magnesium chloride or sea water can be reacted with calcined dolomite to produce magnesia.2&apos;3 In such reactions the MgCl2 of the brine supplies some of the magnesia and the amount of dolomite required is thereby reduced by an equivalent amount, but brines of commercial importance containing magnesium chloride are some distance away from the purest grades of the dolomite of northwestern Ohio. It was decided therefore to concentrate upon the development of a suitable process for separating the lime and magnesia of dolomite, depending upon the dolomite itself as the sole source of magnesia. This would make it possible to place a plant at the dolomite quarry, thus eliminating the cost of transporting the stone and also rendering the calcined magnesia available at a most convenient production point, considering the cost of delivery throughout the steel industry. The selection of a process depending solely upon the dolomite as a source of magnesia also necessarily entails production of the lime content of the dolomite as a by-product. It was recognized that if such a lime by-product could be produced in a suitable form, a plant location in northwestern Ohio would also be advantageous for marketing the lime. The problem, therefore, was the discovery and development of a low-cost process for separating the magnesia and lime of the dolomite of northwestern Ohio and producing each in a form relatively free from the other, and meeting the respective requirements of established markets. A satisfactory solution of this problem has been found, and it is the

Jan 1, 1948

By E. H. Rennhack

When cast hypoeutectic Zn-Ti alloys are rolled, the TiZn15 compound particles arising from eutectic decomposition form a network of fibers promoting improved creep resistance.&apos; The effect is magnified with increasing titanium content and extends to hy-pereutectic concentrations. Strip produced from the latter-type alloys, however, also contains large, primary crystals of the compound that tend to initiate cracking during subsequent fabrication operations. In a study of the influence of various casting modifications on the size and distribution of these crystals, the phase relationships existing between the eutectic and the TiZnIs intermetallic compound in the Zn-Ti system were of major interest. Although several in- vestigators1 4 have explored the equilibria within this compositional range, their results show considerable lack of agreement. Consequently, with the exception of the solvus boundary, the constitution of this system containing up to approximately 1.0 wt pct Ti was . The findings are reported in the present note.

Jan 1, 1967