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By C. J. Wilhem, J. M. Devine

A corrosion-testing apparatus which operates in the field and which will determine the comparative resistance of various ferrous materials to corrosion by gaseous hydrogen sulfide at ordinary temperatures is described. The principle of the uniform method of testing is to allow natural gas containing hydrogen sulfide, direct from its source in the field, to flow over the group of specimens for a given period of time, and subsequently to estimate the corrosion sustained by each specimen by determining its loss in weight. The comparative results obtained when specimens of 47 representative ferrous materials of described typical composition \\ere tested at ordinary temperatures with natural gas containing hydrogen sulfide are given in tables showing average penetration of metal, Inches per year. The primary purpose of the work Mas to determine the possible utllity to the petroleum and natural gas industries of ferrous materials that are commercially available, and no attempt is made to discuss the results of the tests from the metallurgical standpoint. The following is a summary of the results obtained: 1. Steels containing 12 to 27 per cent of chromium showed the highest resistance to corrosion. The presence of nickel In these high-chromium steels did not affect their resistance. 2. Steels containing approximately 5 per cent of chromium showed comparatively high resistance, but somewhat less than that of the high-chromium steels.

Jan 1, 1934

By Edward S. Cook

For several years past, dating particularly from the days of serious "ore-dirt" complications at the Warwick furnace, I have been desirous of providing some safe, quick and easy method of relieving the tuyeres of slag, when the cinder- and iron-notches are chilled through loss of heat in the clucible or when, from dropping or jumping of stock, the molten slag is forcibly driven into the bellyand leg-pipes. Various methods were proposed, but objections of one kind or another always presented themselves, and the subject was postponed to a more convenient season. In the summer of 1887, while running on anthracite alone, 1 found the various expedients in use to be so utterly valueless, that the importance of a practicable tuyere slagging-valve impressed me more forcibly than ever. The holes left in the cast-iron jacket at one side of the bottom of the water-blocks were found to be of no value whatever. The swinging or hinged cap on the elbow of the belly-pipe, while convenient to permit the removal of lag after the belly-pipe was partially or wholly filled, could not be adapted to discharge the slag before solidifying, except at great risk to the men and loss of time just when the constant running of the engine and the keeping of blast on the furnace was of the utmost importance. By removing keys from the caps and holding them in place with props, the slag could be discharged through the tuyeres and belly-pipes, with the engine running, by knocking the props away at a given signal. This method is extremely hazardous to life and limb, and I have always hesitated to make use of it. When the furnace is in such condition as to require the adoption of some method of the kind, the stoppage of the engine, cooling the blast and the contents of the crucible, always aggravates the trouble. When the caps are blown open and the slag is discharged by removal of the props, it is necessary to stop the engine to replace them. An hour or more will elapse before this can be done, as the slag must be partly removed before the tuyeres can be approached by ordinary mortals, and the caps handled and fastened in place again. Any movement of the stock is liable to burn the workman, as he stands, securing the cap in front or at one side of the open belly-pipe.

Jan 1, 1889

By A. L. Barnes

A number of reservoirs have been partially invaded by bottom water. Water flooding such reservoirs can be especially inefficient if the oil has a high viscosity because injected water will under-run the oil and emerge at producing wells without having displaced much oil. A possible means of improving water sweep efficiency would be to precede the water flood with a slug of water purposely thickened with a chemical additive. This possibility has been studied with a scaled laboratory flow model. The investigation was carried out on a model representing a 20-acre five-spot with one set of reservoir condition~. Displacements were performed with water, with viscous-water slugs of 10 and 25 per cent of the pore volume followed by water, and with all viscous water. Displacement tests were made at several rates of injection. For all cases, compared at the same producing water-oil ratio, an increase in rate resulted in an increase in volumetric sweep. The larger the quantity of viscous slug injected, the greater the crossflow of oil ahead of the displacing front and, thus, the lower the WOR during that period of a displacement. This investigation indicates that the injection of aqueous viscous slugs in this type of system would give some additional benefit over conventional flooding by (I) reducing the life of the flood, (2) reducing lifting costs and (3) increasing ultimate recovery. The benefits of a viscous-slug displacement would warrant its use if the viscous water could be created for a few cents per barrel. INTRODUCTION The most appropriate method for water flooding oil reservoirs which have been partially invaded by bottom water has been a problem of considerable interest. Such reservoirs, having good vertical permeability and unfavorable mobility ratios, are difficult to produce efficiently under normal waterflood procedures. Even though the injection wells have been plugged back above the oil-water contact and the water zone has been squeezed off, injection water will enter the formation and not only displace oil, but also much of it will displace the bottom water, thus creating a high producing water-oil ratio at the start of a flood (see Fig. 1). Since the rate of injection and the viscosity of the displacing fluid are the more easily controlled physical parameters of the reservoir, it is quite natural to study their effects on the volumetric sweep of the oil zone and on the producing water-oil ratio. Increasing the viscosity of the displacing fluid has two disadvantages—it reduces the maximum rate of injection into the reservoir, and it costs more than water. It was thought that the injection of a viscous-fluid slug, followed by water, would minimize these two disadvantages, increase the volumetric sweep of the oil zone and reduce the producing water-oil ratio. Water with an additive to increase viscosity would probably be the most effective. The primary purpose of this investigation was to determine the feasibility of injecting viscous-water slugs followed by water to improve or hasten oil recovery while reducing the producing water-oil ratios. The effect of injection rate upon recovery was also investigated. A laboratory model, scaled to a 20-acre five-spot prototype with one set of reservoir conditions, was constructed. Laboratory studies of displacements with (1) water, (2) viscous-water slugs of 10 and 25 per cent of the pore volume followed by water and (3) all viscous water were performed at several rates of injection. THEORY OF SAND MODEL SCALING There are two conventional means of determining scaling criteria. These are dimensional analysis and inspec-tional analysis. Determining scaling criteria by dimensional

By Frederick Prime

IN this supplementary list no titles to which an * is prefixed have been seen by the compiler; and he will be most thankful to have any omissions or inaccuracies in the list sent to him to be published as a second supplement in the next volume of the Transactions. The author is indebted to Messrs. Robert Clarke, of Cincinnati ; Thomas Macfarland, of Towanda; Professor F. W. Simouds, of Chapel Hill; and Professor J. J. Stevenson, of New York, for valuable assistance. CEDAR POINT IRON COMPANY, BALTIMORE, July 31st, 1880. ALABAMA. Geological Survey of Alabama. Report of Progress for 1877 and 1878 ; by Eugene A. Smith, State Geologist. Montgomery, 1879. 8vo., 139 pp., and 4 maps.

Jan 1, 1880

By Jan Law

Problems of oil recovery are attacked from the approaches dictated by the two strikingly dissimilar complexes that comprise an oil reservoir—the fluid complex and the interstitial complex. Knowledge of the fluid complex, due to labors in the fields of fluid mechanics and physical chemistry, has far outdistanced knowledge of the interstitial characteristics of the sand complex. This paper is concerned with the latter and applies the technique of statistics to petrographic facts—namely, porosity and permeability—dealing with what might be called petrometry. Statisticians have long worked within the problem of reconstruction of a universe oi variables by means of samples that comprise a small percentage of the universe from which the samples were drawn. Core-analysis data comply with the requisite of random sampling as stipulated by theoretical statistics. A basic concept of statistics employs t.he following substitution: 1. The results of sampling are arranged as a frequency distribution. 2. The observed frequency distribution is compared with a mathematically precise distribution. 3. If a sufficiently good agreement is found between the two, the precise distribution is substituted in all subsequent operations involving characteristics of the sampled material. This mathematically precise distribution is also known as the normal curve, curve of error, the probability, the Gaussian, and the bell-shaped curve and is describable with but two figures. Further, these two figures, the arithmetic average and the standard deviation, are subject to mathematical manipulation. This paper demonstrates that, in some cases in the Dominguez field of Southern California, if sufficient core-analysis samples are taken over not too great a thickness of sediments, the resultant permeability and porosity assemblages give satisfactory agreement with ilormal curves. It is shown that the indications are strong that oil wells wherein a satisfactory agreement is found are predictable as to productivity. Since the predictions are made by employing the laws of chance that are operative within sedimentation, it follows that the mechanism by which the predictions were made is a basic concept of reservoir mechanics. Therefore, tentative examples are given of the application of normal curves to the solution of problems of primary and secondary recovery. Nature of Permeability Frequency Distributions Core-analysis data are made available as a tabulated depth vs. permeability profile. The nature of the distribution of permeability values within a given strati-graphic interval may be approximated from an array constructed with samples plotted in the order of their appearance with depth (accession number) against their permeability value in millidarcys. A wide variation in the nature of the distribution of K (permeability) values for

Jan 1, 1944

By Jan Law

Problems of oil recovery are attacked from the approaches dictated by the two strikingly dissimilar complexes that comprise an oil reservoir—the fluid complex and the interstitial complex. Knowledge of the fluid complex, due to labors in the fields of fluid mechanics and physical chemistry, has far outdistanced knowledge of the interstitial characteristics of the sand complex. This paper is concerned with the latter and applies the technique of statistics to petrographic facts—namely, porosity and permeability—dealing with what might be called petrometry. Statisticians have long worked within the problem of reconstruction of a universe oi variables by means of samples that comprise a small percentage of the universe from which the samples were drawn. Core-analysis data comply with the requisite of random sampling as stipulated by theoretical statistics. A basic concept of statistics employs t.he following substitution: 1. The results of sampling are arranged as a frequency distribution. 2. The observed frequency distribution is compared with a mathematically precise distribution. 3. If a sufficiently good agreement is found between the two, the precise distribution is substituted in all subsequent operations involving characteristics of the sampled material. This mathematically precise distribution is also known as the normal curve, curve of error, the probability, the Gaussian, and the bell-shaped curve and is describable with but two figures. Further, these two figures, the arithmetic average and the standard deviation, are subject to mathematical manipulation. This paper demonstrates that, in some cases in the Dominguez field of Southern California, if sufficient core-analysis samples are taken over not too great a thickness of sediments, the resultant permeability and porosity assemblages give satisfactory agreement with ilormal curves. It is shown that the indications are strong that oil wells wherein a satisfactory agreement is found are predictable as to productivity. Since the predictions are made by employing the laws of chance that are operative within sedimentation, it follows that the mechanism by which the predictions were made is a basic concept of reservoir mechanics. Therefore, tentative examples are given of the application of normal curves to the solution of problems of primary and secondary recovery. Nature of Permeability Frequency Distributions Core-analysis data are made available as a tabulated depth vs. permeability profile. The nature of the distribution of permeability values within a given strati-graphic interval may be approximated from an array constructed with samples plotted in the order of their appearance with depth (accession number) against their permeability value in millidarcys. A wide variation in the nature of the distribution of K (permeability) values for

Jan 1, 1944

By T. Egleston

AT the Dover meeting of the Institute, Mr. F. A. Canfield showed some of the members a machine which he had invented for dressing mineralogical and geological specimens, which he has since modified and brought to such a high state of perfection, that after having used it for several months in preparing specimens for the cabinet of the

Jan 1, 1876

By T. Egleston

At the Dover meeting of the Institute, Mr. F. A. Canfield showed some of the members a machine which he had invented for dressing mineralogical and geological specimens, which he has since modified and brought to such a high state of perfection, that after having used it for several months in preparing specimens for the cabinet of the

By A. J. Langhammer

Broadly speaking, it may be said that the engineer has two major responsibilities: One is to recommend the choosing of proper machinery and equipment; the other, to assist in the simplification of design, determination of method, and advise about the most suitable material to be used. The products of powder metallurgy enter broadly into both these fields. The oil-cushion, self-lubricating bearing surface on a machine part makes for better machinery and factory equipment, often proves a life-saver in curing difficulties where bearings are overloaded or inaccessible for lubrication, or on installations that with normal practice constitute a problem entailing frequent repairs. On the other hand, other parts may require low porosity approaching solidity. In the second field, powder metallurgy provides many possibilities for improved products, improved performance, solving of technical problems, saving of weight, quiet operation, higher factors of safety, greater flexibility, attractive economies, and so on. Parts We of the automotive industries are making many powdered-metal war-machine parts, both ferrous and nonferrous, including gears, external and internal; ratchets, both external and internal; levers; pillow blocks; sliding blocks; cams; gibs; hubs with external and internal splines, and similar units. Powdered metals play an important part in our war work, as they did in peacetime in the manufacturing of passenger cars and trucks. The art of powder metallurgy is not a panacea. Although on certain parts such operations as turning, boring, facing, reaming, counterboring, milling, countersinking. chamfering, broaching, hobbing, profiling. trepanning, gear cutting, grinding, etc., can be eliminated, there will always be the need for machine tools. Advantages of Powder Metallurgy Simple machining operations often are eliminated by using powdered metal, and also many other intricate operations, some of which are of the type impossible to perform on the most modern production equipment; for instance, an external spline on a flange hub, where the spline must continue to the flange face and at full depth. Another important feature is that some of the machine parts may require a self-lubricating surface at one or more points; for example, proper lubrication of a sliding splined spool, while ordinarily most digcuit, is accomplished automatically with a self-lubricating powdered-metal bearing. Frequently machine parts are made with physical, mechanical and technological advantages unobtainable from cast or forged metals of similar analysis. Thus powder metallurgy offers the designing engineer broader latitude. Similarly, the engineer may take advantage of powder metallurgy in his teamwork with other departments. Another important advantage in powder metallurgy for machine parts is the relatively short time required for tool-up.

Jan 1, 1945

By J. S. Kennedy, G. L. Simard, A. A. Lefrew, C. M. Judson, R. B. Booth

DITHIOPHOSPHATE collectors are commonly used in the flotation of sulphide minerals. Studies of the interaction of a typical dithiophosphate collector with galena surfaces have been previously reported from these laboratories.'* These fundamental studies were carried out by employing phosphorus labeled radioactive dithiophosphate. Radioactivity determinations then could be used to measure readily and accurately the small concentrations of dithiophosphate that are present under conditions of flotation processes. Measurements were made on ground mineral, determining the amount sorbed indirectly from the concentrations in solution; and studies were also made with single crystals, determining the amount sorbed directly by counting the crystal surface. The rates, isotherms and reversibility characteristics of dithiophosphate sorption, the competition between phosphate and dithiophosphate for the mineral surface, and the exchange of sorbed dithiophosphate with dissolved dithiophosphate were studied. These studies have now been extended by sorption measurements in flotations with a Fagergren machine. For this work, the selective flotation of galena and sphalerite from quartz was chosen, using ammonium di-(sec-butyl) dithiophosphate as the collector, sodium cyanide as depressant for sphalerite, and copper sulphate as an activator for sphalerite. While the selective flotation of galena and sphalerite using a single dithiophosphate collector is not typical of flotation practice (two different collectors are generally used), it was found that a reasonably good separation could be obtained by using zinc sulphate with the sodium cyanide in the galena flotation and by cleaning the sphalerite concentrate or by carrying out the sphalerite flotation in an alkaline medium. Data of practical importance on the distribution of collector between the concentrates, tailings, and solutions were obtained, particularly with regard to the effect of copper sulphate and sodium cyanide. In addition to the selective flotation of galena and sphalerite from quartz, single flotations of galena-quartz and sphalerite-quartz mixtures were carried out, along with blank flotations on quartz alone. The present paper describes the results of these experiments. As in previous papers, the term sorption is used to designate uptake of collector by the mineral, without implication as to the nature of the processes involved. Experimental Materials: The mineral system was a ground synthetic mixture of galena, sphalerite, and quartz. The galena was from Galena, Kans., and contained 75 pct lead (theoretical 85.6 pct Pb for PbS); the sphalerite, from Ottowa County, Okla., contained 63 pct zinc (theoretical 67.2 pct Zn for ZnS); and the quartz from Klondike, Mo., analyzed as 99.97 pct SiO,. Sulphur labeled radioactive di-(sec-butyl) dithiophosphate was prepared from SS supplied by the Oak Ridge National Laboratory on allocation from the U. S. Atomic Energy Commission. The synthesis consisted of precipitating barium sulphate, reducing the barium sulphate to barium sulphide, acidifying to form hydrogen sulphide, and oxidizing the hydrogen sulphide with iodine to elemental sulphur.

Jan 1, 1953

By J. S. Kennedy, A. A. Lefrew, C. M. Judson, R. B. Booth, G. L. Simard

DITHIOPHOSPHATE collectors are commonly used in the flotation of sulphide minerals. Studies of the interaction of a typical dithiophosphate collector with galena surfaces have been previously reported from these laboratories.'* These fundamental studies were carried out by employing phosphorus labeled radioactive dithiophosphate. Radioactivity determinations then could be used to measure readily and accurately the small concentrations of dithiophosphate that are present under conditions of flotation processes. Measurements were made on ground mineral, determining the amount sorbed indirectly from the concentrations in solution; and studies were also made with single crystals, determining the amount sorbed directly by counting the crystal surface. The rates, isotherms and reversibility characteristics of dithiophosphate sorption, the competition between phosphate and dithiophosphate for the mineral surface, and the exchange of sorbed dithiophosphate with dissolved dithiophosphate were studied. These studies have now been extended by sorption measurements in flotations with a Fagergren machine. For this work, the selective flotation of galena and sphalerite from quartz was chosen, using ammonium di-(sec-butyl) dithiophosphate as the collector, sodium cyanide as depressant for sphalerite, and copper sulphate as an activator for sphalerite. While the selective flotation of galena and sphalerite using a single dithiophosphate collector is not typical of flotation practice (two different collectors are generally used), it was found that a reasonably good separation could be obtained by using zinc sulphate with the sodium cyanide in the galena flotation and by cleaning the sphalerite concentrate or by carrying out the sphalerite flotation in an alkaline medium. Data of practical importance on the distribution of collector between the concentrates, tailings, and solutions were obtained, particularly with regard to the effect of copper sulphate and sodium cyanide. In addition to the selective flotation of galena and sphalerite from quartz, single flotations of galena-quartz and sphalerite-quartz mixtures were carried out, along with blank flotations on quartz alone. The present paper describes the results of these experiments. As in previous papers, the term sorption is used to designate uptake of collector by the mineral, without implication as to the nature of the processes involved. Experimental Materials: The mineral system was a ground synthetic mixture of galena, sphalerite, and quartz. The galena was from Galena, Kans., and contained 75 pct lead (theoretical 85.6 pct Pb for PbS); the sphalerite, from Ottowa County, Okla., contained 63 pct zinc (theoretical 67.2 pct Zn for ZnS); and the quartz from Klondike, Mo., analyzed as 99.97 pct SiO,. Sulphur labeled radioactive di-(sec-butyl) dithiophosphate was prepared from SS supplied by the Oak Ridge National Laboratory on allocation from the U. S. Atomic Energy Commission. The synthesis consisted of precipitating barium sulphate, reducing the barium sulphate to barium sulphide, acidifying to form hydrogen sulphide, and oxidizing the hydrogen sulphide with iodine to elemental sulphur.

Jan 1, 1953

By E. P. Bucklen, L. J. Prelaz, J. R. Lucas

Today, the future of the coal industry is extremely bright because coal can be produced at a cost which makes it competitive with other energy sources. However, the industry has been forewarned that further cost reductions must be made if it expects to remain a serious contender in the growing energy market. Surface as well as underground operations must be improved. The very same elements which affected production a few years ago still exist today and will continue to be present in the future. Improvements in production mining equipment, mining methods and auxiliary equipment have resulted in reduced costs over the past few years. Efforts must be continued toward further reducing costs in areas which have been previously improved and new areas should be investigated for possible improvements. Therefore, new techniques must be developed which will enable the industry to augment its current efforts in reducing the cost of mining. The logical place to begin evaluating the factors affecting production and cost is in the immediate face area where a substantial part of the total cost of mining is incurred. The coal industry stands to gain much through the development of new techniques for analyzing the numerous variables affecting production and by establishing methods for eliminating or minimizing the adverse effect of those variables which can be controlled. Intuition and trial-and-error methods have been the standard means used to resolve many of the factors which influence production. As a result, many elements are overlooked or ignored because their effects on production are not pronounced and cannot be readily resolved.

Jan 3, 1965

By P. J. Conroy, E. A. Curth

INTRODUCTION In June 1962, the first attempt at longwall mining in Illinois was initiated by Old Ben Coal Company in their No. 21 Mine. Longwalling was continued intermittently using various supports until April 1970. During this period, longwall mining techniques were used on separate occasions at six faces within Mine No. 21. However, due to various problems that developed at each location the faces were eventually terminated. The most significant problems concerned the support systems and roof conditions that were present in the mine during each attempt. Between 1965 and 1972, similar conditions were met by Freeman Coal mining Company during four attempts at longwall mining in their Orient No. 5 and Orient No. 6 mines. In 1975, the U.S. Bureau of Mines and Old Ben Coal Company entered into a cost-sharing agreement to demonstrate the application of longwall mining in Illinois. The first phase of the demonstration was to conduct a premining investigation to review previous attempts at longwall mining, perform rock mechanics tests, and establish support requirements based on the lnvestigation results. The information obtained during the demonstration at Old Ben's No. 24 has been utilized to optimize subsequent face equipment and panel geometry. Mining of the first panel began in September 1976 and was successfully completed in May 1977, and two additional panels were mined under the cooperative agreement. Currently, Old Ben Coal Company is the only longwall mining operator in Illinois. In addition to the face in Mine No. 24, five longwall faces are being operated in four other mines.

Jan 1, 1981

By Ronald K. Linde

Metastable Ag-Cu solid solutions at two compositions beyond the maximum limits of solubility obtainable by quenching from the solid state were obtained by rapid quenching from the liquid state. The process of transformation of the metastable solid solutions into the equilibrium phases was studied by means of X-ray diffraction intensity measurements and electrical-resistance measurements; metallographic examination was also performed. Results are compared with those for an alloy quenched from the solid state at a composition which exists as a solid solution at elevated temperatures. Activation energies for the trans-formation were computed to be 33,600 * 2500 and 33,100 * 2000 cal per g mole for the 60.1 and 75.0 at. pct Ag;Cu compositions, respectively THE kinetics of precipitation in supersaturated solid solutions obtained by quenching from high temperature has been thoroughly studied in many alloys, and detailed investigations of the early stages of nucleation and subsequent growth of the equilibrium phases have been carried out. All of these studies have been made on alloys quenched from the solid state, however, and it is the purpose of this paper to present some of the results on the kinetics of transformation of metastable solid solutions in Ag-Cu binary alloys whose compositions lie outside of the solid-state limits of solubility. Limits of solubility in the solid state can be increased by rapid quenching from the liquid state. This was first demonstrated by Falkenhagen and Hofmann, who obtained appreciable increases in solubility limits of the elements of the first transition series in aluminum by rapid cooling of liquid alloys through contact with a copper mold maintained at liquid nitrogen temperature.' The same basic idea of cooling a liquid alloy by conduction onto a substrate rather than by convection of a gas or liquid (conventional quenching) has been recently revived and extended to very high rates of cooling by Duwez and his collaborators. The new technique was first applied to Ag-Cu alloys because the existence of a eutectic in this system is not predicted by the Hume-Rothery rules of alloy phase formation. Rapid quenching from the liquid state resulted in metastable solid solutions at all concentrations. The kinetics of decomposition of these metastable solid solutions containing 60.1 at. pct Ag;Cu (eutectic composition) and 75.0 at. pct Ag;Cu is the subject of the present paper. EXPERIMENTAL TECHNIQUES Alloys were made in 10- to 20-g heats using silver of purity 99.99 pet and copper of purity >99.999 pct. Components were weighed accurately to 0.1 mg and melted by induction heating in an alumina crucible under an atmosphere of hydrogen. Weight losses amounted to less than 0.02 ~ct in all cases. Rapid cooling from the liquid state was achieved in an apparatus of the type described by Pietrokowsky. 3 In this technique a freely falling drop of molten alloy is caught between a stationary anvil and a fast moving piston, both anvil and piston being lined with copper. The resulting foils were approximately circular (about 2 cm in diam) and from about 50 to 150 u in thickness, depending on the pressure driving the piston. Metallographic samples were prepared for polishing by edge-mounting foils in Quickmount. The mostef-fective etching procedure was found to be: 10 parts NH4OH (concentrated), 1 part H2O2 (30 pct), 5 parts H2O, swab for 5 to 10 sec. The transformation of the metastable alloys to equilibrium was followed by X-ray diffraction and electrical-resistivity measurements. The peak intensity and the integrated intensity of suitable Bragg reflections of the metastable and stable solid solutions were studied with a Norelco dif-fractometer, using nickel-filtered copper KO radiation. The peaks were step-scanned at intervals of 0.05 deg. Using either a Kelvin bridge or a null circuit with a Leeds and Northrup K-2 potentiometer, the changes in electrical resistance due to phase transformation were measured for specimens cut into strips about 20 mm long and 4 mm wide. All resistivity measurements were carried out at liquid-nitrogen temperature. The isothermal heat treatment was accomplished by sealing the samples in argon-filled aluminum containers with stainless-steel O-rings. Containers were then suspended in wax baths with temperatures in the

Jan 1, 1967

By Bernard MacDonald

The writing of this paper was prompted by the discussion by H. M. Chance of the paper written by Thomas M. Chance,l and by the remarks of the editor in which he stated that while the matter contained in discussion did not refer to the original paper it " was presented as of interest to the operators of cyanide and other lixiviation processes dealing with fluid mixtures of varying specific gravity." For some years past the principle enunciated in the discussion referred to has been known to the writer and demonstrated by him to be an efficient and economical way of separating water or solution from solids in the cyanidation, lixiviation or acid leaching of ore pulps. In utilizing this principle in commercial practice he has invented a method whereby not only the separation of solution from solids may be effected in any given tank, but also the counter migration of the solids and solution may be effected continuously through a series of tanks in which the hydro-metallurgical treatment of ore pulps is being carried on. In effect this method is analogous to the counter-current system, but is different physically in that it is carried on throughout a series of tanks on practically the same level, continuously and automatically, by hydrostatic pressure and gravity-flow, without the aid of intervening pumps or elevators, at the same time that agitation is being carried on in the same tanks. In the Parral system, agitation is effected in tanks by a number of air lifts of comparatively small diameter through which the pulp is continuously transferred from the bottom of the tank and spouted horizontally on top of the charge. The spouting force of the several streams thus discharged maintains a rotary flow in the pulp charge which extends from top to bottom of the tank. This continuous transfer of pulp and the spiral flow from top to bottom of the tank maintains the pulp constituents in uniform proportions and meets the requirements of efficient treatment in a most economical manner. The quantity of compressed air required is very small, as the pulp is not lifted but simply transferred from the bottom to the top of the tank charge under hydrostatic balance. Fig. 1 gives a bird's-eye view of two adjoining tanks in any series equipped with the apparatus for producing the separation of

Jan 1, 1919

By D. B. Hunter, H. W. Rosenberg

The titanium-rich portion of the Ti-Pd system was investigated from 0 to 75 wt pct Pd by metallo-graphic and X-ray techniques. A 0 eutectoid occurs at 24 wt pct Pd and 1190°F. Two compoutzds are indicated in the region below 75 wt pct Pd, Ti,Pd and Ti2Pd3. The solubility of palladium its a titanium is low, probably less than 1 pct. In 1960 Rudnitskii and Birunl published a complete version of the Ti-Pd phase diagram. However, their work was in disagreement with the earlier literature in that they reported only one inter metallic compound, whereas three had been reported earlier. In view of these discrepancies, it was therefore necessary to redetermine those portions of the diagram of immediate interest. The following account describes our work on the system over the range of 0 to 75 wt pct Pd. MATERIALS AND METHODS Distilled titanium sponge and elemental palladium were used in the formulation of the alloys; the chemistry of these materials is detailed in Table I. The alloys were prepared as 10 to 50 g blended compacts that were melted into buttons by arc melting under gettered argon on a water-cooled copper hearth. Weighing of the ingredients before and after melting showed that negligible weight changes occurred. Therefore, no analyses were undertaken and the compositions of all alloys are nominal. All alloys were fabricated by hot rolling at 1700°F to 0.070-in.-thick sheet. Scale was removed by sandblasting and pickling in a 5 pct HF-35 pct HNO,, balance H20 solution. For metallographic examination, specimens were mounted after heat treatment transverse to the rolling direction, ground on silicon carbide papers of increasing fineness to 600 grit, and then electro-polished using a solution containing 600 ml me-thanol, 60 ml perchloric acid, 360 ml butyl cello-solve, and 2 ml "Solvent X". Unless otherwise specified, etching of alloys containing up to 42 pct Pd was carried out by swabbing with a 12 pct HN03-1 pct HF aqueous etch where a bright etch was required, or by a 1 pct hydrofluoric in saturated oxalic acid solution where contrast between phases was required. The Ti-52.8 Pd alloy was etched with a solution of 25 ml HF, 40 ml glycerine, 35 ml methanol, and 18 g benzalkonium chloride. For X-ray examination, 1/2-in.-square speci- mens of sheet were mounted flat in a standard 1-in. metallographic mount and ground and polished as above. X-ray diffraction was performed using a Norelco type 12045 Diffractometer, employing CuKa radiation with a nickel filter at 40 kv and 20 ma. Specimens were rotated about the sheet normal during exposure. Although this procedure did not remove the effects of sheet texture from the relative intensities, it had the advantage that oxidation or contaminants entering during preparation of powder samples could not confuse the patterns obtained. RESULTS AND DISCUSSION Fig. 1 illustrates the Ti-Pd phase diagram according to Rudnitskii and Birunl with the work of the present authors superimposed. Both interpretations agree that the system is of the 0 -eutectoid type with an extensive 0-phase field, and that the eutectoid temperature is just below 1200°F. There is also agreement that the solubility of palladium in a titanium is restricted. Our work would indicate that the a solubility of palladium is low, probably less than 1 pct. However, whereas Rudnitskii and Birunl place the eutectoid composition at 41 wt pct Pd, this investigation shows it to be at about 24 wt pct Pd. Moreover, this investigation confirms the existence of compounds at Ti2Pd and Ti2Pd3, whereas Rudnitskii and Birun report only a single Berthol-lide phase covering the TiPd to TiPd, range. Laves et a1.' and Wallbaum, whose work was summarized by Maykuth , reported the existence of Ti2Pd3 and TiPd, in addition to Ti2Pd. More recently, Nevitt and Downe~' have reported the structure of

Jan 1, 1965

By E. J. Fasiska, H. Wagenblast

The dilalion of a ivon by interslilial carbon was measured by two independent techniques —dilatometric mesurements at 719 c and X-ray measurments of the urlil cell parameters a1 room temperature after quenching. The relative expansion per increase in cavbon content by both methods is (2.9 + 0.3) x 10-3 pev at. pcl C nrzd is temperature- independent within experimental error. This corresponds to (6.3 5 0.6) cu cm per g-atom for the partial gram-atomic volume of carbon in a iron-only slightly smaller than the atomic volume for iron in the same temperature vange. THE only previous quantitative study of the dilational effect of carbon dissolved in a iron was performed in 1934 by Burns1 which, at the time, generated some discussion of possible sources of experimental error.2 For a system of such widespread importance, we felt that a new investigation was merited. Both X-ray diffraction and dilation measurements were used to determine the expansion of the a iron lattice by dissolved carbon, avoiding as much as possible any previous experimental problems and deficiencies. The dilation method at solution temperature offers not only measurements which are free of residual strain but also, in conjunction with the room-temperature X-ray measurements, a method to detect any large temperature dependence of the partial gram-atomic volume of carbon. To insure that quenching strains did not affect the room-temperature X-ray measurements, wire specimens of constant carbon content but different diameter were examined for such an effect. SPECIMEN PREPARATION The material used for both experimental techniques was "Ferrovac E" iron received in the form of 19-mm-diam rod and stated as having the following impurity contents: C, Cr, Cu, Mn, P, and V, each in the range of 10 to 50 ppm; Co, O, Mo, S, and Si, 60 to 100 ppm; W, 200 ppm; Ni, 230 ppm; N, 4 ppm. The stock material was cold-swaged to 0.71 mm diam for the Debye-Scherrer X-ray camera specimens and portions were cold-rolled from 6.3 mm diam to 0.79- and 0.25-mm sheet for X-ray diffractometer and dilation measurements. The wires were annealed in wet hydrogen for 6 hr at 840°C and 15 hr at 720°C, and then quenched into 0°C water. A chemical analysis for carbon after this treatment gave 0.0046 + 0.0014 at. pct C. Three portions of these wires were subsequently held at 719°C in three different hydrogen + methane mixtures and then quenched, resulting in carbon concentrations of 0.0283, 0.0598, and 0.1067 at. pct C by chemical analysis. After carburizing, the wires were swaged to 0.48 mm and electroplated with silver to prevent carbon loss during subsequent heat treatment. The final heat treatment consisted of holding the wires at 72 1°C for 5 min in a He-2 pct H mixture followed by quenching into 0°C brine. The wires were held at room temperature for a few minutes to remove the silver plating using a phosphoric acid-hydrogen peroxide solution, and then stored in liquid nitrogen until the measurements were made. EXPERIMENTAL TECHNIQUE A) Dilation Measurement. The dilatometer consisted of a gas-atmosphere vertical tube furnace modified so that length changes of a ribbon-shaped specimen could be measured externally. This was done by installing a gas-tight mercury seal at the top of the furnace as shown schematically in Fig. 1. The specimen (21.0 cm long, 1.27 cm wide, and 0.25 mm thick) was suspended in the center of the furnace by 3-mm-diam quartz rods with the upper one passing through the cap of the mercury seal. Above the cap, the upper quartz rod was coupled to a lever exerting a load of about 25 g (-12 lb per sq in.) on the specimen and having a 10 times mechanical magnification. The vertical position of a marker at the other end of the beam was read with a traveling microscope with a precision of 0.01 mm. The temperature gradient of the furnace was meas-

Jan 1, 1968

By C. P. PERIN, DONALD BELCHER

T HE production of pure iron by electrolyzing solutions of its salts has been the object of scientific curiosity and research for about 80 years; and in the last two decades a realization of the unusual physical and chemical qualities of electrolytic iron has turned the attention of chemists and metallurgists toward a commercial application of this accumulated knowledge. Thus Burgess and Hambuechen in America, . Cowper-Coles in England, and Fischer in Germany- devised methods, more or less successful, for the electrolytic refining of iron, but none of these processes has yet attained large-scale operation. During the war some interesting ,work was done in France and England on building up worn or defective machine parts by electrodeposition of iron. It remained for the Société "Le Fern in France to carry on the process commercially. For six years Les Fonderies et Forges. de Sainte-Maire et Gravigny and the works of Bouchayer & Viallet at Grenoble have manufactured pure-iron boiler tubes in competition with established practice. The French process originated in the researches of Anthelme Boucher in 1910, and was, not put into operation until several years of experimentation had passed.

Jan 1, 1921

By R. E. Head

Some mixtures of sulphide and oxide ores from the Tintic district in Utah are of a sufficiently good grade to be shipped to the smelter without beneficiation. In mining this type of ore, however, a material tonnage of ore of a similar composition but of lower grade is obtained. It is a question of economics whether such ore should be shipped with a certainty of a small return or concentrated if that would yield a sufficiently increased return to amortize plant construction and upkeep and yield a higher rate of profit than at present. It may be assumed that the tonnage of this borderline ore is constantly increasing and that eventually it will attain such proportions as to justify plans for milling on a relatively large scale. Under existing conditions, the producer of mixed sulphide and oxide ores is not greatly concerned about the physical characteristics of his ore or of its mineralogical complexities, since his contract with the smelter calls for payment on the basis of chemical analysis. When concentration is contemplated an entirely different picture is presented. Percentages of valuable metal content must then be con-sidered in terms of minerals, for it is in the form of minerals that recoveries are made and losses sustained. In describing the performance of a given flotation mill and reagent combination, it may be stated as a generality that a specific percentage recovery of valuable elements is made. Technically, however, the concentrator is really constructed and the reagents are selected to recover the valuable minerals. These considerations must be given prominence in discussing borderline ores from the Tintic district because of their physical characteristics and mineralogical composition. Because of these peculiarities they may be justly termed complex, since their lead, silver, and copper contents are each represented by two or more minerals of different chemical composition and presenting widely divergent physical properties. This paper sets forth the results of a microscopic study of a type of borderline ore from the Tintic district that is now being treated by direct smelting. A

Jan 1, 1939

By R. E. Head

Some mixtures of sulphide and oxide ores from the Tintic district in Utah are of a sufficiently good grade to be shipped to the smelter without beneficiation. In mining this type of ore, however, a material tonnage of ore of a similar composition but of lower grade is obtained. It is a question of economics whether such ore should be shipped with a certainty of a small return or concentrated if that would yield a sufficiently increased return to amortize plant construction and upkeep and yield a higher rate of profit than at present. It may be assumed that the tonnage of this borderline ore is constantly increasing and that eventually it will attain such proportions as to justify plans for milling on a relatively large scale. Under existing conditions, the producer of mixed sulphide and oxide ores is not greatly concerned about the physical characteristics of his ore or of its mineralogical complexities, since his contract with the smelter calls for payment on the basis of chemical analysis. When concentration is contemplated an entirely different picture is presented. Percentages of valuable metal content must then be con-sidered in terms of minerals, for it is in the form of minerals that recoveries are made and losses sustained. In describing the performance of a given flotation mill and reagent combination, it may be stated as a generality that a specific percentage recovery of valuable elements is made. Technically, however, the concentrator is really constructed and the reagents are selected to recover the valuable minerals. These considerations must be given prominence in discussing borderline ores from the Tintic district because of their physical characteristics and mineralogical composition. Because of these peculiarities they may be justly termed complex, since their lead, silver, and copper contents are each represented by two or more minerals of different chemical composition and presenting widely divergent physical properties. This paper sets forth the results of a microscopic study of a type of borderline ore from the Tintic district that is now being treated by direct smelting. A

Jan 1, 1939