Search Documents

By A.A. Gustafson

In diamond or churn drilling for the prospecting of ore bodies, two products can be used for quantitative analyses; i.e., the core and the cuttings, or sludge. Some operators prefer an assay of core; others insist that the sludge be sent for analysis. Both must recover the sludge for check samples or for assays if there is no core recovery for any particular section of the diamond-drill hole. The Freeport Sulphur Co. found that numerous cumbersome sludge boxes or barrels were inconvenient and delayed drilling. The sludge settled slowly in the ordinary shallow, rectangular diamond-drill boxes and its total removal from the container was difficult, time-consuming and unsatisfactory; and sampling of deposits of which the metal contents are easily concentrated, as in ores containing cinnabar, gold and silver, is subject to error if the boxes are not thoroughly cleaned. Mr. Charles Ballard, dredge superintendent at Freeport's operation at Grande Ecaille, Louisiana, developed a portable cone while he was in charge of prospecting a mercury property near Tonopah, Nevada, in 1940. Ballard later improved the design while the settler was being used at a manganese property in New Mexico. The operation is based on the "free settling" of comminuted particles in a quiescent liquid. The ordinary sludge box discharges over a lip 8 to 12 in. wide and consequently the water has sufficient velocity so that the discharge water is never clear. The cone settler used by Free-port Sulphur Co. discharges over the entire circumference, which gives a discharge ltp of 9 ft. in the size of cone used at the cinnabar and manganese prospects. Consequently, the velocity of the discharge water is slow enough so that all fine material settles and the discharge water is clear. When the drilling of a sample interval is complete, the sludge can be drawn off by the time the driller is ready to cut another sample. Thus, only one cone is needed per drill. The cone has been used by Freeport successfully in churn-drilling a manganese deposit, in diamond-drilling a mercury deposit, and in diamond-drilling a deposit of ore containing tin, copper, gold and silver. The cone is greatly superior to the old methods of collecting sludge and is now used on all Freeport drilling campaigns in the western states, both for surface and underground drilling. Fig. I shows the important details of a cone designed for average operating conditions, 30 in. in diameter and 36 in. high. Abnormal conditions may require some revisions in design. Fig. 2 shows a working drawing. A hose or pipe larger than the one used to convey water from the pump to the swivel head of the string of rods is connected to the stuffing box at the collar of a diamond-drill hole, The usual T-connection is used. It is not necessary to use a stuffing box if the top of the cone can be placed lower than the collar of the hole. Then the return water and cuttings can be made to flow by gravity. This hose or pipe discharges the cuttings of the drill bit and the return

Jan 1, 1943

By A. A. Gustafson

In diamond or churn drilling for the prospecting of ore bodies, two products can be used for quantitative analyses; i.e., the core and the cuttings, or sludge. Some operators prefer an assay of core; others insist that the sludge be sent for analysis. Both must recover the sludge for check samples or for assays if there is no core recovery for any particular section of the diamond-drill hole. The Freeport Sulphur Co. found that numerous cumbersome sludge boxes or barrels were inconvenient and delayed drilling. The sludge settled slowly in the ordinary shallow, rectangular diamond-drill boxes and its total removal from the container was difficult, time-consuming and unsatisfactory; and sampling of deposits of which the metal contents are easily concentrated, as in ores containing cinnabar, gold and silver, is subject to error if the boxes are not thoroughly cleaned. Mr. Charles Ballard, dredge superintendent at Freeport's operation at Grande Ecaille, Louisiana, developed a portable cone while he was in charge of prospecting a mercury property near Tonopah, Nevada, in 1940. Ballard later improved the design while the settler was being used at a manganese property in New Mexico. The operation is based on the "free settling" of comminuted particles in a quiescent liquid. The ordinary sludge box discharges over a lip 8 to 12 in. wide and consequently the water has sufficient velocity so that the discharge water is never clear. The cone settler used by Free-port Sulphur Co. discharges over the entire circumference, which gives a discharge ltp of 9 ft. in the size of cone used at the cinnabar and manganese prospects. Consequently, the velocity of the discharge water is slow enough so that all fine material settles and the discharge water is clear. When the drilling of a sample interval is complete, the sludge can be drawn off by the time the driller is ready to cut another sample. Thus, only one cone is needed per drill. The cone has been used by Freeport successfully in churn-drilling a manganese deposit, in diamond-drilling a mercury deposit, and in diamond-drilling a deposit of ore containing tin, copper, gold and silver. The cone is greatly superior to the old methods of collecting sludge and is now used on all Freeport drilling campaigns in the western states, both for surface and underground drilling. Fig. I shows the important details of a cone designed for average operating conditions, 30 in. in diameter and 36 in. high. Abnormal conditions may require some revisions in design. Fig. 2 shows a working drawing. A hose or pipe larger than the one used to convey water from the pump to the swivel head of the string of rods is connected to the stuffing box at the collar of a diamond-drill hole, The usual T-connection is used. It is not necessary to use a stuffing box if the top of the cone can be placed lower than the collar of the hole. Then the return water and cuttings can be made to flow by gravity. This hose or pipe discharges the cuttings of the drill bit and the return

Jan 1, 1943

By A. S. Adams

A GLANCE at the list of papers1 that have been published since 1920 on the general subject of flotation suggests the variety of ideas that exist regarding the underlying cause of the phenomenon. Among these ideas, we find several coherent theories, but none that adequately and completely explain the phenomenon. Ralston2 and Bains3 suggested an electrical theory which has to do with the attachment of mineral particles to a bubble by the attraction of unlike electrical charges. This theory has its root in the fact that a bubble of air in pure water is electrified in such a way that the surface is negatively charged while the body of the water is positively charged. This result, which was first discussed by Helmholtz, also obtains when the water contains anything except a high concentration of hydrogen ions, or ions which are trivalent or tetravalent. The theory also holds that the mineral particles have positive charges on their surfaces, and so there is attachment between bubble surface and mineral particles by the old law of electrostatics, which states that unlike charges attract.

Jan 1, 1928

By A. M. Nicholas

WheN attempting to lift mill pulp containing a considerable percentage of wolframite, in an ordinary bucket elevator, difficulty was encountered from the tendency of the tungsten minerals to settle, on account of their high specific gravity. Lifts not exceeding 20 ft. (6 m.) could be accomplished without particular difficulty, because there was insufficient time for consolidation of the heavy minerals in the bottom of the bucket; but with higher lifts, the heavy tungsten minerals would settle so solidly that when the bucket turned over at the top of the elevator the contents could be only partially dumped. In this case it was necessary to lift the material a distance of 34 ft. (10m.); hence some means had to be adopted to prevent settling, at least to such an extent that the material could be dumped from the buckets. To reduce the carrying time to a sufficient extent would have required a belt speed of 475 ft. (144.7 m.) per minute, which was not feasible. It was decided to try, by vibrating the belt about midway of its span, to keep the material sufficiently agitated during elevation to prevent settling. Underneath the rising side of the belt was placed a 12-in. (30.48-cm.) idler pulley, 18 ft. (5.5 m.) up in the total lift of 34 ft. The idler pulley was set eccentric by % in. (19 mm.) and it was hoped that the vibration thus imparted to the belt, running at a speed of 280 ft. (85 m.) per minute, would prevent settling in the buckets. It was found that the pressure of the belt on the idler, due to the small inclination of the elevator, was not sufficient to overcome sliding on the idler, and the agitation was insufficient to accomplish the desired purpose. The idler was then connected to the drive shaft of the elevator through an intermediate pulley, gearing down to a speed of 20 r.p.m., so that a positive vibration was imparted to the belt; this imparted enough motion to the belt to prevent settling and the contents of buckets dumped satisfactorily. Protecting Elevator Belts When elevating, from the crusher, a rock which was very sharp and abrasive, considerable difficulty arose from cutting of the belt under-

Jan 1, 1918

By H. M. Chance

WITHIN the last 10 years the subject of mine taxation in its relation to coal-mining interests has come to have growing importance, not only to those engaged in the mining of coal, but also to the owners of land underlain by coal. A disposition has developed among legislators to accept the principle, which has been laid down y many judicial decisions, that coal underlying the surface must be regarded as a part of the real value of all properties so underlain, and as such is chargeable with such burdens of taxation as the necessities of the government may impose. These necessities arise from the normal expense of maintaining State and local governments, and in the past have been met principally by, taxes based upon assessments of real estate values, which values in many cases have been confined principally or wholly to the value of the surface, without taking into consideration the value of minerals underlying the surface. It is not proposed here to deal with the question of Federal taxation, whether levied on production, or on products transported from one State to another, or exported from the country, or upon thegross or net earnings of corporations engaged in interstate commerce, or upon the production of materials which may be transported from one State to another, or levied. upon the profits or upon the obligations of corporations. The present discussion will be confined to the appraisal of coal lands as assessed for State, county, township, or borough taxation. The methods heretofore and at present in use in the different States vary widely and have resulted in more or less litigation. Discussions appearing from time to time in the technical and trade journals and in the proceedings of mining and engineering associations frequently direct attention to the need for the adoption of fixed principle in levying taxes, and of uniform methods for applying such principles, but there does not seem to be a general demand from the public for the adoption of such methods.

Jan 7, 1914

By R. C. de Lange

An improved replica technique is developed for a nondestructive study of the nucleation and growth of fatigue cracks. Three different growth stages of a fatigue crack were observed. An initial stage of high growth rate is followed by a long period of very slow growth, until finally a third period of high growth rate leads to fracture. THE metal-fatigue process is of a very complex nature. The experimental approach towards fatigue is susceptible to many minor influences which, together with the unavoidable scatter in testing results, makes the interpretation a matter of extreme care. The generally accepted fact that, in a homogeneous material, the fatigue cracks start at a free surface indicates that surface studies may contri-but in an essential way to a better understanding of the fatigue mechanisms. Indeed metallographic observations of the fatigue phenomena have been very fruitful in the last decade. The study of extrusions, intrusions, and persistent slip bands has contributed much to the present knowledge of the early processes in fatigue.' The drawback of the current metallographic techniques lies in the fact, however, that either observations of fatigue phenomena had to be made in a destructive way after an only partly executed test or a sequence of observations on the same test bar was only possible on notched specimens.2 4 In both cases an uncertainty exists as to the nucleation and growth of the fatigue crack in an unnotched test bar, where the crack can start at any place of a large area and develops in a test bar, which is macroscopically

Jan 1, 1964

By R. E. Head

Under existing economic conditions, the treatment of gold ores occupies an outstanding position in metallurgical activity. The increased price of gold has automatically brought about a reclassification of old dumps and low-grade orebodies, and many that formerly were considered valueless are now being vigorously investigated and worked. This situation has developed problems that have taxed the ingenuity and ability of metallurgists to the utmost. Some gold ores give a high extraction of gold by standardized methods of treatment; other ores of apparently similar character yield but a relatively small percentage of their gold when treated by the same processes. Surface Contamination The experience gained by microscopic study of numerous gold ores and tailings has shown that there are pronounced differences in the physical characteristics of the minerals composing them, more especially of the gold. Repeated studies of tailings from flotation and cyanidation of gold ores has established the fact that surface contaminations on gold particles are often directly responsible for high gold losses; comparison of gold particles isolated from flotation concentrates and the resulting tailings have showed that the clean gold has been recovered and the tarnished or contaminated gold invariably lost in the tailing. Obviously, it is not possible to make such a comparison of gold ores treated by cyanidation, as the clean gold has been taken into solution; but when the gold found in cyanide tailing has a tarnished or coated surface, one may infer, with a reasonable degree of certainty, that the clean gold has been extracted. This premise is supported by experimental evidence obtained by isolating particles of tarnished gold and exposing them to cyanide solution in small parting cups. In one such experiment, tarnished gold particles picked from a cyanide tailing showed but slight evidence 01 dissolving at the end of 27 days. In this test, a cyanide solution of 1.6 11). per ton was used and the leach solution was decanted arid renewed every

Jan 1, 1939

By R. E. Head

Under existing economic conditions, the treatment of gold ores occupies an outstanding position in metallurgical activity. The increased price of gold has automatically brought about a reclassification of old dumps and low-grade orebodies, and many that formerly were considered valueless are now being vigorously investigated and worked. This situation has developed problems that have taxed the ingenuity and ability of metallurgists to the utmost. Some gold ores give a high extraction of gold by standardized methods of treatment; other ores of apparently similar character yield but a relatively small percentage of their gold when treated by the same processes. Surface Contamination The experience gained by microscopic study of numerous gold ores and tailings has shown that there are pronounced differences in the physical characteristics of the minerals composing them, more especially of the gold. Repeated studies of tailings from flotation and cyanidation of gold ores has established the fact that surface contaminations on gold particles are often directly responsible for high gold losses; comparison of gold particles isolated from flotation concentrates and the resulting tailings have showed that the clean gold has been recovered and the tarnished or contaminated gold invariably lost in the tailing. Obviously, it is not possible to make such a comparison of gold ores treated by cyanidation, as the clean gold has been taken into solution; but when the gold found in cyanide tailing has a tarnished or coated surface, one may infer, with a reasonable degree of certainty, that the clean gold has been extracted. This premise is supported by experimental evidence obtained by isolating particles of tarnished gold and exposing them to cyanide solution in small parting cups. In one such experiment, tarnished gold particles picked from a cyanide tailing showed but slight evidence 01 dissolving at the end of 27 days. In this test, a cyanide solution of 1.6 11). per ton was used and the leach solution was decanted arid renewed every

Jan 1, 1939

By W. D. Kruger

Methods for analyzing flooding or cycling projects by means of two-dimensional flow calculations are presented in the literature. The use of these methods allows the determination of optimum operating conditions for such projects and provides information on pattern efficiencies, relative flow rates, pressure distributions and floodout histories. The accuracy of such analyses depends on the basic reservoir data employed, especially the absolute permeability distribution in the reservoir; however, absolute permeability data normally are determined from well flow tests and/or core measurements and are so limited in quantity and quality that they do not adequately describe the reservoir flow properties. A calculation procedure is presented for determining the areal permeability distribution in the reservoir. Use of the procedure allows verification of the basic reservoir data through the matching of past reservoir conditions, thereby providing proper data for reliable predictions of future operations. The calculation procedure is a numerical technique based on a mathematical model of the reservoir and is designed for solution by means of an electronic digital computer. Results from field application of this procedure are presented. Permeability distributions from measured data are compared to those calculated to indicate the need for the analysis. Comparisons of field-measured and calculated pressure distributions are given to establish the validity of the calculation procedure. The conclusions of this paper are (I) use of the calculation provides data that allow a match of past reservoir conditions and thus reliable prediction of future operations; and (2) the procedure should, where applicable, be used to provide adequate reservoir data for use in two-dimensional flow calculations and related reservoir analyses. INTRODUCTION One means of providing more precise engineering control over reservoir operations during all stages of depletion is to develop some type of model to simulate the reservoir, using information developed from the behavior of the prototype to predict the performance of the actual reservoir. The use of mathematical rather than physical models for this purpose has been gaining in importance recently because of the application and availability of electronic computers. Mathematical models avoid instrumentation difficulties and allow easier handling of large-scale problems. At present, analyses employing two-dimensional models are common, and thought is being given to the use of models in three dimensions. The use of multi-dimensional models is necessary to show not only what is occurring in the reservoir, but also where in the reservoir the phenomena of interest are taking place. Methods for analyzing flooding or cycling projects by means of two-dimensional numerical models are presented in the literature. The use of these methods allows the determination of optimum operating conditions for such projects and provides information on pattern efficiencies, relative flow rates, pressure distributions and floodout histories. The applicability of numerical models and the results of using such analyses have been presented through field examples. The references indicated here discuss fully the data necessary to build the mathematical reservoir model and the way the model is used to study or predict the future performance of the reservoir. The accuracy of the analysis of such projects depends on the basic reservoir data employed in the construction of. the model. In order to be sure the model represents the reservoir, it must be used to match some known set of reservoir conditions, i.e., to match past reservoir performance. The accuracy of the model is directly dependent upon the absolute permeability distribution in the reservoir; however, absolute permeability data are normally determined from well flow tests and/or core measurements, and are so limited in quantity and quality that they do not adequately describe the reservoir flow properties. There is always the need for better data and for verification of existing data. The purpose of this paper is to show the use of the mathematical model to match past performance in flooding or cycling projects, the use of numerical techniques to adjust the basic absolute permeability data if necessary so that a match is obtained, and in this way to generate the effective areal permeability distribution of the reservoir. A review of the basic concepts of the numerical model will be given, followed by a discussion of the data-adjusting technique for matching past performance. TWO field examples will be cited to show

By E. O. Lilge, H. Siebert

A design of a multiple-bomb leaching unit particularly suited for the study of heterogeneous reactions, i.e. sol id-liquid-gas interfaces at high temperatures and pressures is presented. The component parts and overall design are described and illustrated in detail. The system has been tested by a limited number of experiments and found to work satisfactorily. Heterogeneous reactions at solid-liquid-gas interfaces, at high temperatures and pressures, are studied in either autoclaves1'4 or bombs5'9. Autoclaves are usually fairly large vessels which have a stirring arrangement incorporated in the design. Mechanical design limits the use of these vessels to relatively low temperatures and pressures. They are particularly well suited to rate or kinetic studies. Bombs can be designed to be operated at high temperatures and pressures, and are smaller vessels; because of this, stirring arrangements are not easily incorporated. In this paper a multiple-bomb system is described, that has been designed to incorporate the desirable features of both the autoclave and the bomb. The described unit has flexibility for an over all study of leaching. Most of the component units in this assemblage are standard equipment, designed and produced by well known manufacturers. No claim is made to the design of this equipment, and although described in some detail, this is done merely for clarity in the elucidation of the system presented. The general layout of the multiple-bomb assemblage is shown in Fig. 1A and 1B. The basic units in this system are: 1) 6 stainless steel 100 ml bombs (Fig. 4)

Jan 1, 1964

By Phillip E. La Moreaux

Fluoride, generally less than 0.5 ppm, is present in ground water from rocks of Paleozoic age and older, in northern and eastern Alabama. Some of the water-bearing formations in the Coastal Plain area of the State yield water with as much as 6.8 ppm fluoride. IN June 1940, the U. S. Geological Survey, in cooperation with the Geological Survey of Alabama, began a study of the ground-water resources of the part of Alabama where water is obtained from Cretaceous rocks. The purpose of the study was to determine the quality, quantity, occurrence, and availability of ground water in that area. These studies have been expanded to include ground-water investigations in the area of Tertiary rocks, or southern quarter of the State, and certain areas in northern Alabama. The first report issued on these studies was by C. W. Carlston,1 of the Alabama Geological Survey. In the present paper all references to ground-water data for the Cretaceous area are taken from this earlier publication. In 1945, the Dentistry Division of the Alabama Department of Public Health became interested in the correlation of tooth decay and mottled enamel with the chemical quality of ground water used for public supplies in the State. Through a cooperative arrangement between the State Department of Public Health and the Ground Water Division (now Branch) of the U. S. Geological Survey, a report by the author2 was published in 1948. These two reports give accurate information on the occurrence of fluoride in the Coastal Plain of Alabama. At present, only scattered information is available on fluoride in ground water of the crystalline-rock or Piedmont area and for the Paleozoic area of Alabama, but it is hoped that in the future more complete information on the presence of fluoride in ground water in these areas can be collected. Outline of Geology and Ground Water: As described by Adams,3 the State of Alabama includes parts of two major geologic divisions, the Appalachian region and the Coastal Plain. The boundary between these divisions is irregular and is known as the Fall Line of the Atlantic and Gulf Coast States. The Fall Line enters Alabama near Phoenix City, extends westward to Wetumpka, Clanton, and Tuscaloosa, and then swings northwestward to the northwest corner of the State. The Appalachian region in Alabama includes three major provinces, the Piedmont province, the Appalachian Ridge and Valley province, and the Appalachian Plateau province (fig. 1). The rock formations in the Piedmont province in east-central Alabama are mainly of pre-Cambrian age, chiefly crystalline schists and gneisses injected by younger igneous rocks (fig. 1, I). They are faulted and folded and have a complicated structure. These rocks are the oldest and among the most complex rocks in the State. Generally, only small yields of ground water are obtained from rocks in this area. Even though ground water is of great importance for the development of domestic and farm supplies in rural areas and a few small industrial and municipal wells, yields in the area from individual wells generally range from 5 to 25 gpm and rarely exceed 50 gpm. The geologic formations of the Appalachian Ridge and Valley province and the Appalachian Plateau province (see fig. 1, II, and III) are separated on the basis of their structure. These rocks are of Paleozoic age, ranging from Cambrian to Carboniferous, and comprise a succession of formations consisting chiefly of shale, sandstone, limestone, and dolomite, aggregating many thousands of feet in

Jan 1, 1951

By Phillip E. La Moreaux

Fluoride, generally less than 0.5 ppm, is present in ground water from rocks of Paleozoic age and older, in northern and eastern Alabama. Some of the water-bearing formations in the Coastal Plain area of the State yield water with as much as 6.8 ppm fluoride. IN June 1940, the U. S. Geological Survey, in cooperation with the Geological Survey of Alabama, began a study of the ground-water resources of the part of Alabama where water is obtained from Cretaceous rocks. The purpose of the study was to determine the quality, quantity, occurrence, and availability of ground water in that area. These studies have been expanded to include ground-water investigations in the area of Tertiary rocks, or southern quarter of the State, and certain areas in northern Alabama. The first report issued on these studies was by C. W. Carlston,1 of the Alabama Geological Survey. In the present paper all references to ground-water data for the Cretaceous area are taken from this earlier publication. In 1945, the Dentistry Division of the Alabama Department of Public Health became interested in the correlation of tooth decay and mottled enamel with the chemical quality of ground water used for public supplies in the State. Through a cooperative arrangement between the State Department of Public Health and the Ground Water Division (now Branch) of the U. S. Geological Survey, a report by the author2 was published in 1948. These two reports give accurate information on the occurrence of fluoride in the Coastal Plain of Alabama. At present, only scattered information is available on fluoride in ground water of the crystalline-rock or Piedmont area and for the Paleozoic area of Alabama, but it is hoped that in the future more complete information on the presence of fluoride in ground water in these areas can be collected. Outline of Geology and Ground Water: As described by Adams,3 the State of Alabama includes parts of two major geologic divisions, the Appalachian region and the Coastal Plain. The boundary between these divisions is irregular and is known as the Fall Line of the Atlantic and Gulf Coast States. The Fall Line enters Alabama near Phoenix City, extends westward to Wetumpka, Clanton, and Tuscaloosa, and then swings northwestward to the northwest corner of the State. The Appalachian region in Alabama includes three major provinces, the Piedmont province, the Appalachian Ridge and Valley province, and the Appalachian Plateau province (fig. 1). The rock formations in the Piedmont province in east-central Alabama are mainly of pre-Cambrian age, chiefly crystalline schists and gneisses injected by younger igneous rocks (fig. 1, I). They are faulted and folded and have a complicated structure. These rocks are the oldest and among the most complex rocks in the State. Generally, only small yields of ground water are obtained from rocks in this area. Even though ground water is of great importance for the development of domestic and farm supplies in rural areas and a few small industrial and municipal wells, yields in the area from individual wells generally range from 5 to 25 gpm and rarely exceed 50 gpm. The geologic formations of the Appalachian Ridge and Valley province and the Appalachian Plateau province (see fig. 1, II, and III) are separated on the basis of their structure. These rocks are of Paleozoic age, ranging from Cambrian to Carboniferous, and comprise a succession of formations consisting chiefly of shale, sandstone, limestone, and dolomite, aggregating many thousands of feet in

Jan 1, 1951

By R. R. Harvey

Recent evidence has indicated that the films forming at crude oil-water interfaces are the result of naturally occurring su,rface-active components in the crude oil rather than oxidation products resulting from exposure of the oil to air. Since the presence of such films may strongly affect the displacement of oil from porous media, a knowledge of their composition and formatiorz is of fundamental importance. In this study, without the assumption of a specific mechanism, film formation is considered to involve the transfer of a weakly surface-active species in solution in the oil to the oil-water interface. The film gas law and the Gibbs adsorption equation may thus he applied to the system. The rigid films which form upon decrease of the oil-water interfacial area are considered a result of the very slow rate of re-solution of the film material into the oil. When the shrinkage of the interface is very rapid, the amount of film material leaving the interface is negligible, and the system may then be treated in the same manner as an insoluble film. The combination of these treatments leads to a new concept of the film factor in which it may he quantitatively related to the concentration of film-forming material at the interface. Suitable experiments can then yield the following information. 1. Original concentration of surface-active species in the oil. 2. The change of concentration with time. 3. Concentration of surface active species at the interface. 4. The change of this concentration with time. 5. Interfacial tension of the system at any time and its variation with time. 6. Equilibriunz concentrations for a given set of conditions. 7. Concentration requirements for solid film formation. 8. Molecular diameter of the adrorbed species. These calculations may be made solely from data taken from measurements on the original oil. While using the pendant drop method of interfacial tension measurement of crude oil-water systems, Bartell and Niederhauser' remarked on the thin, transparent, pliable, solid films or membranes which were often formed at the interface between crude oil and water. As a result of their observations of these films, Bar-tell and Niederhauser concluded: 1. The films are formed by material from the oil adsorbed at the interface rather than by a reaction at the interface. 2. The adsorption of the film-forming material is a rather slow process. 3. There are good indications that the process is reversible; i.e., the film constituents may re-dissolve into the oil. 4. The film will spontaneously spread over any new surface formed. 5. The process of adsorption at the interface is accompanied by a decrease in the interfacial tension of the system. Although they had proved that film formation was not due to a reaction at the interface, Bartell and Niederhauser were unable to demonstrate conclusively whether these film-forming constituents were present in the original reservoir oil or whether they were formed as oxidation products after exposure of the oil to air. Recent evidence seems to point to their presence in the original oil. Although the true nature of the film-forming constituents is still uncertain, these conditions would be fulfilled by the assumption of the presence of a slightly soluble surface-active component in the original oil. This component would migrate to a freshly formed interface because it would thereby lower the free energy of the system. The component at the surface constitutes an expanded monolayer which would become compressed, upon retraction of drop, due to the slow rate of re-solution of the film components into the bulk of the oil. It is possible, by involved extraction processes, to separate or at least concentrate this film-forming fraction. However, using the assumptions made above, the technique of monolayer film study may be applied to reveal much of the nature of the adsorbing material without resorting to an actual separation of the film-forming constituents.

By C. D. Hall

This paper may be divided into two main parts: (1) analysis and data to show that Eq. 6 adequately correlates the authors' experimental data, and (2) the assertion that Eq. 20 "should permit scale-up with data taken from one pipe diameter for Newtonian, inelastic non-Newtonian, and viscoelastic fluids, such as dilute polymer fracturing fluids, which produce considerable pressure reductions." The authors might well recommend that this broad grouping of fluid types could be correlated by using Eq. 6 (requiring data from at least two pipe diameters). On the other hand, Eq. 20 is only shown to be adequate for conditions within the range of the present data set. Specifically, predictions by Eq. 20 for diameter scale-up to casing sizes would give larger deviations than implied in Table 2, and scale-up for some other fluids that give large drag reduction could be grossly in error. The description of a class of fluids "which produce a diameter family of straight parallel lines on a log (d?p/4L) vs log (8 v/d) plot. . ." defines a necessary condition for using Eq. 6; i.e., that s shall be constant for each fluid. The proposal that Eq. 20 is applicable to turbulent flow of such fluids is equivalent to saying that the spacing of these parallel lines, with A being constant, will be found to correspond to m = -1.20 for all such fluids. Table 1 shows the values of m derived from data on 16 non-Newtonian fluids. The key statement of this paper is that the diameter exponents "do not vary significantly from . . . -1.20." In statistical terms, this says that the m value for each fluid, which was obtained from all the measurements made on that fluid. has not been shown to be different from the arithmetic mean of the m values for the 16 fluids tested. This implies that the group mean, -1.20, is a more reliable value to use for an individual fluid than is the m value derived from the data on that fluid alone. No statistical test is described to support the key statement that the diameter exponents do not vary significantly from -1.20. Such a test would have to take into account that each individual m value is shown to correlate the pressure gradients for its fluid, with only about 3 percent standard deviation over the diameter range covered. That is, the m value is not the result of a single independent measurement. Thus, it would not be sufficient, or valid, to compare the deviation of one of the m values with the variance of the 16 values of m about their mean. An alternative interpretation of the key statement is that the diameter exponents do not vary appreciably from -1.20; i.e., that using -1.20 does not cause serious inaccuracy. Table 2 seems to be offered in support of such an assertion. However, such a statistical treatment (1) is unnecessary and (2) cannot lead to any valid scale-up generalization. The amount of error introduced by using a 1"wrong" value of diameter exponent — i.e., -1.20 instead of m — is determined by Eq. 6. The ratio of the pressures predicted by Eqs. 6 and 20 for scale-up from ds in small pipe to d, in casing is The pressure for 30-percent calcium carbonate slurry (m = -1.112) in 10-in. ID pipe would be predicted 30 percent higher by Eq. 6 than by Eq. 20, if based on tests in 0.5-in. ID pipe. The data set tested in Table 2 represents only a limited sample of pipe diameters (ratio of about 4:l) out of the population of diameters that would

Jan 1, 1970

By C. W. Chen

MARTENSITE transformations in ß Cu-Al alloys have been studied by Greninger1 and other investigators. According to Greninger, the parent phase ß1 an ordered body-centered-cubic structure obtained from ß phase by suppressing the eutectoid decomposition, transforms into an ordered hexagonal-close-packed phase in composition containing 12.9 to 14.7 pct Al. The M, temperature decreases with increasing aluminum content; for the alloy containing 14.5 pct Al, for example, the ß1??' transformation occurs below room temperature. More recently, Kurjumow2 studied the transformation in ß Cu-Al alloys with the addition of nickel. His report stimulated new interest in the subject due to the observation of completely reversible transformation without hysteresis in the transformation temperature ranging from 10° to —10°C. In the present paper some characteristics are described of the transformation of Cu-Al-Ni alloys that were partly studied by Kurjumow. Experimental Procedure High purity copper (99.999 pct) and aluminum (99.99 pct) and electrolytic nickel were used in the preparation, by the Bridgman technique, of single crystal specimens which contained aluminum and nickel of 14.5 and 0.5 to 3.0 pct, respectively. Polished surfaces were prepared mechanically. Specimens were then chemically etched to remove distorted material, homogenized at 1000°C for several hours, and quenched drastically to room temperature in a 10 pct NaOH bath to produce the parent phase ß1. The transformation was studied under a microscope and, in some cases, recorded by means of motion pictures. A device similar to that designed by Greninger and Mooradian3 was used to cool and reheat the specimens. Results and Discussion When the specimens were cooled below room temperature, the ß1 to ?' transformation began at 10°C with the appearance of ?' crystals In relief, Fig. la. As the specimen temperature dropped further, the transformation continued, either by the growth of the ?' crystals, with the ß1 — ?' interface moving into the ß1 phase, Fig. 1c and 1d, or by the formation of new ?' crystals, Fig. 1b. As a consequence of the former process, banded structure is observed as a common feature of the low temperature phase. According to the theory of the formation of martensite by Wechsler, Lieberman, and Read,' the bands of ?' phase are probably twin-related, as is the case in the diffusionless phase change of In-T1 alloys,5 but this was not revealed by X-ray tech- niques. New ?' crystals, in needle form, often emerged suddenly across the ?' bands during the transformation. These acicular crystals then grew, both in length and in width, see Fig. 2a through 2d. The transformation on cooling is completed at about -35°C. Upon heating, the reverse transformation started at —10° C, in a manner nearly opposite to the transformation on cooling, and completed at 35°C. There was no noticeable change in the transformation temperature when the nickel content was varied within the limits previously mentioned. Through control of the specimen temperature, the transformation can be started, stopped, or reversed at will. This phenomenon has frequently been observed in the martensite transformation of many nonferrous alloy systems. Other systems are Au-Cd6 and In-Tl.5 ow-- ever, in the latter systems, the transformation is accomplished by single interface motion if the specimen composition is homogeneous and the temperature gradient in the specimen is uniform and sharp, whereas in the Cu-Al-Ni specimens, only multiple interface transformation is observed. The speed of the interface motion appears to be a functionof the rate of temperature change and the temperature gradient across the specimen length. In one case, in which the temperature increased at the rate of 10°C per min and there was no temperature gradient along the specimen axis, the speed of the disappearance of a ?' plate was determined, by the study of the motion pictures made, to be 26 µ per sec. Quench markings were observed on the polished surfaces of specimens. The markings were grouped into one or more sets of different orientations, and were parallel in each set. The ?' plates formed in subsequent transformation were parallel to the markings, indicating that the ?' plates and the quench markings had the same geometric relation-ship to the ß1 matrix. The quench markings on two intersecting surfaces of a specimen were therefore used in the determination of the habit plane of transformation, by the trace method suggested by Barrett.' Results obtained from five sets of markings in three specimens indicate that the habit plane is an irrational plane about 2" from one of the {221} planes. This is very close to the habit plane (3" from 221 planes) of ß Cu-Al alloys containing more than 13.0 pct Al.1 The martensite transformation of Cu-Al-Ni alloys is reproducible. No sluggishness was found between consecutive transformation cycles, although a slight difference in the distribution pattern of the ?' plates was observed, compare Figs. Id and 2d. The transformation can be strain-induced. This characteristic has been tested by a simple method. When a specimen was elastically strained slowly in a vise, ?' plates were gradually produced in the same fashion as during transformation on cooling, This test was done at room temperature, and thus above the M,

Jan 1, 1958

By L. L. Oriard

INTRODUCTION In order to make effective plans for the control of blasting effects, it is necessary to understand a few basic principles relating to the behavior of explosives. For the purposes of discussing this behavior, it is convenient to divide blasting effects into two zones. The first zone is the non-elastic zone in close proximity to the explosive charge where rupturing of the rock occurs. For this zone, our discussion will be oriented towards the factors which affect the rock breakage, and the means of controlling the limits of this breakage. The second zone is that zone more remote from the charge location where elastic vibrations are transmitted through the surrounding medium. In this zone, we are interested in the factors affecting vibration intensity, and the means of controlling the intensity so that no damage is done to structures, utilities, or excavated slopes. It has been easier to gather data in the elastic zone, because the stress levels are lower and time durations are longer. The instrumentation for obtaining data in this zone can be less rugged and less sophisticated. Consequently, more information of ad empirical nature has been gathered. In the non-elastic zone, there has been more dependence on theory, fewer measurements, and more questioning of the validity of the measurements. In spite of these questions, there has been an encouraging advancement in knowledge in recent years, both theoretical and empirical, of the effects that take place close to the source of an explosion. When discussing the problems encountered in rock excavation, we can simplify the terminology by referring to the physical phenomena encountered in the non-elastic zone as a problem in "over-break". The phenomena in the elastic zone could be called "vibration effects". Although there is some interdependence between the two, it is possible to control the rock breakage to neat surfaces and still have very high vibration levels. Similarly, it is possible to control the vibrations to moderate levels and still have a great deal of overbreak. THE ROCK BREAKAGE ZONE First, let us discuss the effects in that zone close to the blast source that we might call the non-elastic zone. This is the zone of cratering, breakage, rupturing, and fracturing. These effects will vary with the site conditions, and a meaningful, specific analysis could

Jan 1, 1972

By Anson Hayes

FOR the purpose of the following discussion the word "research" is interpreted as including all phases of development work on methods of manufacture, metallurgical characteristics, and uses of iron and steel. Research in the iron and steel industry then includes both plant re- search and laboratory research. Since iron and steel came into being, the steel consumer's plant and the steel producer's plant have been important factors in the development of the steel industry. Good minds have always been associated with both consumer and producer plants, so marked progress was made in the industry even when these were the only types of research and development groups in action.

Jan 1, 1937

By J. W. H. Clare

An equilibrium isotherm at 550°C is given for ternary alloys rich in aluminum containing 0 to 15 wt pct Cr and 0 to 20 wt pct Mn. Phases encountered are: aluminum solid solution; stable temary compound G; and MnAl8,. In addition, a limited number of alloys were annealed at 450°C to check for differences from the 550°C isotherm. These experiments limited the composition of the G phase at 550°C and further experiments established that the G Dhase is not stable above 590 ± 1 °C. RAYNOR and Little1 established several equilibrium isotherms using aluminum-rich alloys containing up to 5 pct of the elements chromium and manganese. These isotherms showed that, in addition to an a solid solution and the two binary intermediate compounds 8 and MnAl6, a stable ternary compound ex-isted in the system. This phase was called the G phase because of its ghostly appearance in micro-sections. Little, Raynor, and Hume-Rothery2 found a similar phase in binary aluminum-manganese alloys and, as a result of their experiments, concluded that the G phase was a metastable phase existing in the aluminum-manganese system. This phase was stabilized by the addition of chromium. The constitutional work of Raynor and Little,' although showing the existence of the G phase in the aluminum-chromium-manganese system, did not establish precisely the composition limits of the phase or the temperature above which the phase became unstable and disappeared from the system. The work described in this paper was undertaken to provide this information. An examination of the previous work' showed that an isotherm at 550°C would provide the required data regarding composition in the shortest possible time, as the (a + G) phase field narrows considerably at higher temperatures. The same work showed that the G phase ceased to exist between 580° and 595°C. A more precise estimate of the transformation temperature would therefore be obtained by annealing selected alloys at successively higher temperatures beginning at 580°C. EXPERIMENTAL PROCEDURE 1) Materials Used—The experimental alloys were prepared from four master alloys containing 15.00 w pct Cr, 15.28 wt pct Cr, 19.80 wt pct Mn, and 19.38 wt pct Mn which were made from super-purity aluminum, electrolytic chromium, and electrolytic manganese. The aluminum was of 99.996 pct purity, the principal impurities being copper, iron, and silicon. The chromium and manganese were 99.9 pct pure, the principal impurities being antimony, calcium, and magnesium. 2) Preparation of the Experimental Alloys—The alloys were prepared in 20-g quantities by melting together the requisite amounts of master alloy and aluminum in an alumina-lined crucible and, after thorough stirring with an alumina rod, cast into a cold copper mold to give ingots 1/4 in. in diam and 3 in. in length.

Jan 1, 1960

E. W. Parker, Washington, D. C.: In connection with Mr. Blauvelt's paper, a brief sketch of the development of by-product coke-making in the United States may prove of interest. The first radical departure from the prevalent beehive oven to the by-product retort oven was inaugurated in 1891 by the Solvay Process Company, at Syracuse, N. Y. In that year was begun the construction of 12 Semet-Solvay ovens, which were completed in 1893. During 1893 these ovens produced 12,850 tons of coke, an average.of a little over 1000 tons each. In the following year the production amounted to 16,500 tons, not quite 1400 tons per oven. These 12 ovens were in reality an experiment, the success of which was attested by the addition to the same plant of 13 more ovens, begun in 1895 and completed in 1896. They were followed by the construction in 1896 of 25 ovens of the same type at Sharon, Pa., and 50 more at Dunbar, Pa. These 100 ovens represented the total number of Semet-Solvay ovens completed and in operation up to the close of 1897. The construction of 180 more, however—120 at Ensley, Ala., and 60 at Benwood, near Wheeling, W. Va.—was begun in 1897. The plant for the latter is laid out for double the number stated. The 60 ovens begun in 1897 have now been completed. An initial plant of Otto-Hoffman ovens was built at Johnstown, Pa., in 1895, and began making coke in 1896. One hundred and twenty additional ovens of this type were begun in 1896 and completed in 1897 at Glassport, near McKeesport, Pa. During the present year 100 Otto-Hoffman ovens are being added to the plant at Johnstown, and 400 of the same type are in course of construction at Everett, near Boston, Mass. The plant at the latter place is laid out for a total of 1200 ovens.

Jan 1, 1899

By CHARLES HOPPER

In preparing the Steep Rock Lake iron ore body for mining, it was necessary to drain Steep Rock Lake. Using diamond drills, a cut 1800 ft long, 100 ft wide, and maximum depth of 95 ft amounting to 300,000 cu yd of material, was excavated in Greenstone to provide a drainage channel. This was done under the general contractor C. A. Pitts, of Toronto, who in turn employed a diamond drill contractor, Boyles Bros., to do the drilling. The method of excavation was selected be- cause a clean square cut and grade could be maintained in the bottom of the channel. Bootlegged holes would have left blocks of rock in the corners which would have created a situation which would have become progressively worse as the open cut advanced from one side of the ridge to the other.

Jan 1, 1949