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By E. V. Foran

Among the many newer disclosures that have accompanied the petroleum industry's progressively deeper exploratory drilling is the increased frequency with which the operators are encountering reservoirs of which the products at the time of discovery exist wholly or predominantly in the gas phase. The popular term "distillate pool" is most often used within the industry when referring to this type of reservoir, and in this paper the term is used in that sense. These pools have been observed in many different surroundings. In some places the entire reservoir is filled with the wet gas containing its water-white condensible products in the gas phase but apparently with no dark oil or other hydrocarbon liquids in the reservoir. The 8200-ft. horizon in the Big Lake field in West Texas is a good example of this type. At other places the wet, or distillate-bearing, gas may form a large gas cap directly overlying and in contact with an extensive reserve of dark oil. Oklahoma City, Kettleman Hills, the 8500-ft. horizon in the Big Lake field, and many others are examples of this type. There are also many places in which the wet distillate-bearing gas fills nearly the entire reservoir space, while the dark oil occupies only a narrow, bandlike zone, which marks the boundary of the reservoir along its lowest productive contour. The heavier components of these deep pool gases are generally water white in color, a large portion of which are condensible in a conventional oil and gas separator, when operated under pressures of the order of 400 to 800 Ib. per sq. in. Although the water-white products recovered in the separator sometimes have end points of 650" F. and higher on standard Engler distillation, they occur only in the gas phase in the reservoir. It is entirely possible that even some small amounts of dark colored reservoir components may occur in the gas phase when the temperature is 300" F. and pressures exceed 6000 Ib. per sq. in. Close approaches to these conditions have been encountered in the deepest producing wells. The condensible content of the deep reservoir gases of the many pools that have been tested or produced to date shows a wide variation in both condensible content, per 1000 cu. ft. of gas, and physical character.

Jan 1, 1939

By C. D. Stahl, R. Sandrea

This investigation was made to evaluate the comparative effects of the viscosity and the phase behavior of the buffer fluid in the composite solvent displacement of Bradford crude from waterflooded sandstone cores. Buffer slugs of propane, naphtha and other refined hydrocarbons exbihiting increasingly favorable viscosity ratios and decreasing solubility relationships, respectively, with Bradford crude, were used in long Berea sandstone cores. The secondary slug was isopropyl alcohol. The results indicate that higher oil recoveries are obtained for increasingly favorable phase relationships even when these are accompanied by unfavorable viscosity ratios within the range studied. Moreover, when propane is used as a buffer slug with an adverse viscosity ratio of 36, it gives higher oil recoveries than at a similar size slug of an any1 alcohol having a viscosity ratio of 1.09. The investigation was extended to the study of the effect of flooding rate on oil recovery. Residual Bradford crude was displaced from a 6-ft Berea sandstone core at rates varying from 0.3 to 30 ft/ day. The results show that as flooding rates were increased above or decreased below a minimum range of 1 to 2 ft /day, displacement efficiency increased considerably. INTRODUCTION In recent years, the alcohol slug process as a means of tertiary recovery has been the subject of many investigations. Gatlin and Slobod showed the advantages of the combination solvent slugs over the previous single-slug process.1 The combination slugs require less total slug material to obtain similar oil recoveries. The basic combination process involves injecting a primary or buffer solvent which is preferentially oleophilic, followed in turn by a water-driven slug of isopropyl alcohol. This procedure ensures that the buffer slug, which is miscible only with the reservoir oil, displaces and replaces the oil and is in turn displaced, together with the water, by the isopropyl alcohol slug miscible with both fluids. Likewise, for those reservoir oils that show some degree of phase incompatibility with isopropyl alcohol, as does Bradford crude, a proper buffer solvent can artificially make the alcohol process technically feasible. From an economic standpoint, propane or LPG would be the most appropriate primary solvent to be used in the field; however, Taber, et a12 have indicated that the alcohol process becomes highly inefficient in the displacement of light hydrocarbons because of the entrapment of these hydrocarbons during the stabilized bank formation. Moreover, since materials such as propane have such low viscosities, adverse viscosity ratios with most reservoir oils would be penerated, thereby possibly further reducing the efficiency of the buffer solvent. This paper presents the results of an experimental study of the comparative effects of viscosity ratio and phase relationships on the displacement efficiency of Bradford crude by means of dual solvents. The work was extended to include the effect of flooding rate on oil recovery. Rates within the range of field and laboratory values were used. EXPERIMENTAL PROCEDURE APPARATUS The porous media used in this study consisted of two 10-ft and one 6-ft Berea sandstone cores, 3-in. in diameter. These were cast in galvanized steel pipe of 31/2-in. ID and the annulus was filled with Armstrong cement. The 10-ft cores were assembled by connecting two 5-ft units, which were joined together by 8-in. steel flanges fitted to the pipe. Intimate contact between the two sections was obtained by inserting a thin disk of the same sandstone between the core faces. The outlet and inlet ends of the cores were covered with threaded pipe caps. The injected fluid was gravity fed to two variable-rate positive-displacement pumps. The fluids were filtered before entering the core and the effluent was collected in an automatic fraction collector and

Jan 1, 1966

By J. C. Donnell, O&apos

Sinking an inclined ventilation shaft at the Never Sweat mine of The Anaconda Co. has required a unique underground hoisting arrangement because the shaft changes direction from vertical to 71.5º. Access to the project is made through the High Ore shaft to the 2800-ft level, then by crosscut to the bottom of the vertical Never Sweat shaft. The 71.5º incline shaft starts at this point, which makes an unusual operation as the 60-cu ft sinking skip coming up the incline changes into a vertical position above the 2800-ft level before going into the dump scrolls. This requires both rollers and guide shoes on the skip. Coming up the incline to the collar of the shaft the loaded skip enters into a guard before reaching the vertical section. The tendency of the surface- mounted Never Sweat hoist is to lift the front wheels of the skip off the track, so the guard keeps the skip on the rails during the transition.

Jan 11, 1965

By Victor V. Damiano

THOMPSON1 proposed a very convenient nomenclature in which an imaginary regular tetrahedron was used to facilitate the analysis of dislocation interactions in fcc materials. The faces of the tetrahedron were constructed parallel to four different sets of (111) planes, and the six edges of the tetrahedron then represented the six 1/2 [110] Burgers vectors. The lines which joined the midpoint of a tetrahedron face with the ends of one of its edges represented the Burgers vectors of the partial dislocations into which the six 1/2 [I101 Burgers vectors dissociate. Using Frank&apos;s2 notation, all of the dislocations and their partial dislocations were identified and numerous possible interactions were postulated. The case of hexagonal crystals is unfortunately more complex, but it appears convenient to introduce a system similar to that of Thompson1 to describe the various slip planes and Burgers vectors encountered in cph structures. The system proposed has limited application but serves to identify the following slip systems {0001} <l20>, {1010} <1120>,

Jan 1, 1963

By Jacob T. Wainwright

The object of this paper is to describe some efforts and observations by the writer relating to this subject. Althongh the usual type of&apos; blast-furnace is a most efficient device for smelting and melting purposes, it is not suitable for utilizing the cheaper grades of fuel, such as coal-slack and certain gaseous fuels. This problem not only involves the consideration of the furnace as a suitable apparatus, but also embraces the consideration of the chemical and calorific properties of the proposed fuel. In the hearth of the ordinary blast-furnace an extremely high temperature is maintained. This extreme temperature is due to the complete combustion of the fuel in the hearth, and before the gases reach the zone of fusion their temperature is reduced, by the absorption of carbon, 2300 degrees Fat). In a smelting-furnace, the maintenance of this extreme temperature at the hearth becomes useless when it can be reduced without

Jan 1, 1889

By Paul H. Lu

This paper proposes an unconventional, simple, and practical method of measuring mining-induced ground stresses with hydraulic borehole pressure cells. The method is a direct ground stress measuring technique. It does not require the value of deformation modulus for back-calculation of stresses; instead, it directly measures the ground stress in situ. The applicability and practicality of the technique are shown by two case studies. The technique may be applied to monitoring a stress buildup that may lead to mine roof failure or to rock and coal outbursts.

Jan 1, 1984

By C. S. Chang

PEARL starch, a corn starch prepared with a minimum of alteration, is a good selective depressant for iron oxide minerals.1 From what is known of the complex chemistry of corn starch, there is evidence that it consists of a mixture of saturated giant polymeric molecules, both straight and branch- chained, the constituents consisting of glucose units with hydroxyl radicals as active or polar groups. To add to the existing knowledge of the chemistry of the flotation process, it is desirable to ascertain the effects on the corn starch as an iron oxide depressant when some of the hydroxyl radicals are replaced by other active groups that are common to flotation reagents. The ideal way to carry out this investigation would be to test reagents containing different active groups derived from corn starch. The preparation should be such that the reagents possess the same degree and location of substitution and are ac- companied by little or no degradation of the starch molecules. This, of course, is almost impossible to realize, as it is difficult to control the degree and location of substitution as well as to prevent degradation of the starch molecule during preparation.

Jan 9, 1954

By Magnus Troilius

The importance of having methods for the rapid and accurate determination of manganese in modern steel manufacture cannot be overestimated. The method adopted in the laboratory of the Midvale Steel Works is very satisfactory, and I think it will be of interest to some of the members to give a description of it. Before giving the more detailed account of the manipulations, a review of some well-known methods and chemical facts may not be out of place. The " bromine and ammonia" process, as fully described in the tenth volume of the Transactions of this Institute, was certainly an improvement on the methods in which fixed alkaline salts were used, as these gave invariably too high resnlts, as generally carried out. But the separation of all the iron before the manganese was, in both methods, a source of great inconvenience and delay.

Jan 1, 1884

By Joseph Hartshorne

The attention which this process has attracted, especially in Europe, has led me to believe that members of the Institute would be interested in a report of the progress which has been made in the year and a half that has elapsed since my paper on the subject was read at the Colorado Meeting of this Institute. As already described in that paper (Duns., xxvi., 380), this process is a modificatioii of the open-hearth steel manufacture, whether acid or basic, collsistillg essentially in the division of the charge between two furnaces, one of which is charged about two hours earlier than the other, and tapped into the other after the charge in the latter has become fluid, the slag of the first bath being removed from it during the transfer. This description still remains true as far as it goes, but further experience has demonstrated that circumstances will very materially modify the relation of the two furnaces to each other, and the character of the work done in each of them. The function of the primary furnace has become more clearly and entirely that of doing the rough work of desiliconiziug and dephosphorizing, while that of the second or finishing-furnace has become almost entirely that of decarburizing and finighing the heat. To indicate these developments and their results is the object of this paper. In order to avoid needless repetition, I shall try to accomplish part of this object by giving a short resume&apos; of what has been published elsewhere on this subject since my former paper was read. This will at least enable those interested to study the matter for themselves from original sources. Since that time the following papers have been read and published: " The Bertrand-Thiel Process of Making Steel," by Percy C. Gilchrist (Cleveland Institution of Engineers, Session of 1896-

Jan 1, 1899

ATHOUGH the open-hearth charge contributes CO, CO2, and water vapor to the combustion gases and absorbs oxygen from them, in the main the thermal effects in the melting charge and molten bath can be considered independently of those in fuel combustion, the latter being regarded simply as the source of any extra heat required to finish a heat of steel. First of all, it should be remembered that a large percentage of the heat supplied to the bath is furnished by oxidation of the various elements in the charge itself. If this charge consisted of 80 to 100 per cent of hot metal and the oxidation were obtained by blowing in air or oxygen, as is the case in the Bessemer converter, then the net heat absorption would be negative, that is, the bath would contribute part of the heat required to keep the melting chamber hot, in addition to that contained in the finished steel and slag. In actual open-hearth practices, probably the nearest approach to this is in the duplex furnace, charged with Bessemer-blown metal and some hot metal, where very little heat is required to complete the refining and nearly all the heat energy from fuel combustion is used to keep the roof and walls of the melting chamber up to around 2900 to 3000°F. (1600 to 1650°C.) so that the bath will not cool off during the refining. The other extreme is with all-cold charges containing around 80 per cent steel scrap and 20 per cent cast iron or cold pig iron, in which case a very large proportion of the heat in the bath at tap is supplied from the fuel combustion. THERMAL EFFECTS IN MELTTNG In the previous chapter it was pointed out that in a typical heat, the fuel furnishes about four million B.t.u. per ton of steel produced. The heat required for the metallurgical processes is not easily defined in useful manner (as is shown later), but it ranges downward from about one million B.t.u., depending not only on the charge but on the manner of calculation. In any event this requirement appears quite small in comparison with the heat furnished by the fuel and invites

Jan 1, 1944

By John Croston

IN the closing months of 1936 the copper industry gave every evidence that it was at last on the threshold of an improved era. At the beginning of the year prices stood at 9 1/4¢, which in itself was a great improvement over prices prevailing for the three previous years. Industry generally was showing signs of moving forward in this country, and business was definitely good in certain foreign quarters. The threat of war and prep-arations for rearmament in Europe and Asia acted as a further stimulus purchasing. By midsummer the situation had so improved and stocks to been so reduced that the cartel of foreign producers (including American producers with foreign mines) decided to increase the produc-tion quota to 75 per cent on Aug. 1. Large-scale buying gave continued strength to the price and by Oct. 1 the quota was increased to 80 per cent, and again on Oct. 15, to 85 per cent. Notwithstanding this the price of copper continued its advance and on Nov. 1, with stocks declining con-tinuously, the cartel increased operations to 95 per cent, then to 105 per cent on Nov. 5. In the meantime the domestic producers, because of the great increase in home consumption, had increased their production by nearly one-half. At the close of the year copper sold at 120 per pound, and since the turn of the present year has reached 170. This rapid increase has not been wholly justified. Much of the increase was due to the legitimate demands of recovering industry, but rearmament orders plus accumulation of reserve stocks in case of war, purchases in anticipation of labor strikes and purely speculative activities on the London Metal Exchange accounted for the balance. Certainly in view of the state of industry and the general world price level, it appears unnecessarily high. Talk of a copper shortage is sheer nonsense, the recent condition in the market being created by overbuying, leaving but a small volume for speculative supplies. It takes some months for an increase in mine output to reach the market, but production is again overtaking apparent consumption, stocks have begun to increase, and this, together with the reopening of many small

Jan 1, 1937

By A. William Johnson

It was pointed out in an earlier paper1 that our understanding of the atomic mechanism by which diffusion occurs in metallic alloys is scarcely in an advanced state. This unsatisfactory condition is the result not of any lack of interest, but of the difficulty of designing experiments that .will yield suitable data. The diffusion coefficient of an alloy, measured in the usual way, is simply a number specifying the rate of homogenization of a nonhomo-geneous metal; this number, of itself, can furnish neither the rate at which the individual atoms move nor information as to the mechanism by which they move. It does not necessarily follow, however, that such information cannot be obtained, even if the path to be followed is still not clear. Much success has been attained in the study of diffusion in ionic crystals. A number of experiments, for which there are few counterparts in connection with metals, yield information often indicating a detailed mechanism by which diffusion probably occurs. From such work, quite acceptable theories of lattice imperfections have been developed by Wagner, Schottky, Frenkel, Jost and others.2 It is postulated that real crystals of stoichiometric composition contain, in equilibrium, certain imperfections of which the most importarlt types are: (I) vacant cation sites, with an equal number of interstitial ions; (2) vacant anion sites, with an equal number of interstitial ions; (3) equal numbers of anions and cations in interstitial positions; (4) equal numbers of vacant anion and cation sites. The classification of a particular crystal according to this scheme then follows from studies of the variation of electrical conductivity with pressure of the electronegative component surrounding the crystal, with ion size, and with temperature; other physical phenomena, such as the Hall effect, have aided in establishing the classification. The relative mobility of the anion and cation may be determined by chemical analysis of the salt at the electrodes following electrolysis. With such information, and knowing that one ion never occupies the lattice site normally belonging to an ion of opposite sign, it is usually possible to ascertain the diffusion mechanism. It is clear that the same experiments are not applicable to metal crystals, and substitute experiments that yield as much information have not yet been devised. Much can be learned, however, about the mobilities of the two* kinds of atoms in alloys by the use of radioactive metals as indicators. Only one such experiment has been performed in the past. In 1933, Seith and Keil,3 in an effort to explain the great difference between the rate of diffusion of gold in lead and of lead in lead, measured the rate of diffusion of radioactive lead in 3 gold-lead

Jan 1, 1942

By A. William Johnson

It was pointed out in an earlier paper1 that our understanding of the atomic mechanism by which diffusion occurs in metallic alloys is scarcely in an advanced state. This unsatisfactory condition is the result not of any lack of interest, but of the difficulty of designing experiments that .will yield suitable data. The diffusion coefficient of an alloy, measured in the usual way, is simply a number specifying the rate of homogenization of a nonhomo-geneous metal; this number, of itself, can furnish neither the rate at which the individual atoms move nor information as to the mechanism by which they move. It does not necessarily follow, however, that such information cannot be obtained, even if the path to be followed is still not clear. Much success has been attained in the study of diffusion in ionic crystals. A number of experiments, for which there are few counterparts in connection with metals, yield information often indicating a detailed mechanism by which diffusion probably occurs. From such work, quite acceptable theories of lattice imperfections have been developed by Wagner, Schottky, Frenkel, Jost and others.2 It is postulated that real crystals of stoichiometric composition contain, in equilibrium, certain imperfections of which the most importarlt types are: (I) vacant cation sites, with an equal number of interstitial ions; (2) vacant anion sites, with an equal number of interstitial ions; (3) equal numbers of anions and cations in interstitial positions; (4) equal numbers of vacant anion and cation sites. The classification of a particular crystal according to this scheme then follows from studies of the variation of electrical conductivity with pressure of the electronegative component surrounding the crystal, with ion size, and with temperature; other physical phenomena, such as the Hall effect, have aided in establishing the classification. The relative mobility of the anion and cation may be determined by chemical analysis of the salt at the electrodes following electrolysis. With such information, and knowing that one ion never occupies the lattice site normally belonging to an ion of opposite sign, it is usually possible to ascertain the diffusion mechanism. It is clear that the same experiments are not applicable to metal crystals, and substitute experiments that yield as much information have not yet been devised. Much can be learned, however, about the mobilities of the two* kinds of atoms in alloys by the use of radioactive metals as indicators. Only one such experiment has been performed in the past. In 1933, Seith and Keil,3 in an effort to explain the great difference between the rate of diffusion of gold in lead and of lead in lead, measured the rate of diffusion of radioactive lead in 3 gold-lead

Jan 1, 1942

THE first session, on alloys, took place on Feb. 20, Mr. Hibbard presiding in Mr. Campbell&apos;s absence. The session covered papers on manganese, chrom-ium, and silicon-iron systems. The paper by Mr. Wohr-man was presented by title. This paper showed that manganese produced many of the effects generally at-tributed to carbon and indicated that our ideas on manganese-bearing carbon steels will have to be modi-fied. Mr. Krivobok discussed this paper at length, the gist of the discussion being that Mr. Wohrman had not taken sufficient precautions in carrying out some of his work, particularly as to the effect of silicon content. Mr. O&apos;Neill&apos;s paper was also submitted by title and no discussion was presented. Mr. Kinzel showed an accu-rate determination of .the carbon-free chromium-iron loop obtained by means of a specially constructed tele-scopic dilatometer. The loop ends at 12.2 per cent chromium and the A-3 line at 900° is unaffected by chromium content. The A-4 line runs from 1400° to 900° at 12.2 per cent chromium as an oblique hyperbola. Mr. Armstrong noted that the brittleness in high chromium alloys is often attributed to the gamma trans-formation and, according to Mr. Kinzel&apos;s diagram, this was impossible, as the alloys contain a great deal more than 12 per cent chromium. Mr. Kinzel pointed out that the presence of carbon in the commercial alloys caused the elongation of the loop and made possible local austenite transformation. Mr. Styri discussed the relations of the coefficients of expansion as shown in Mr. Kinzel&apos;s diagram. Mr. Corson presented the iron-silicon diagram as he has worked it out, showing a pre-viously unknown intermetallic compound, Fe3Si, to-gether with characteristic martensitic microstructure varying with the heat treatment. This compound formation is the real cause of brittleness in certain re-gions of the iron silicon system. Dr. Hoyt believed some of the evidence presented by Mr. Corson to be in contradiction to the phase rule. Mr. Corson, however, explained that true equilibrium does not exist under the conditions at hand so that the diagram was accurate in spite of the discrepancies. The meetings of the subcommittee on the physical chemistry of steel making were interspersed through-out the day. Mr. Feild presided and a program of future activities was outlined. This includes plans for a symposium at the next annual meeting and methods for interesting physical chemists, particularly those in the universities, in the steel man&apos;s problems. This committee has been newly formed and bids fair to be especially active. The Iron and Steel Committee met at lunch at the Engineers&apos; Club at noon, with Dr. Mathews presiding. After disposing of the food the report of the Nominat-ing Committee was called for, and the following were elected as officers for 1928: R. H. Sweetser, chairman; F. C. Langenberg and W. J. Priestley, vice-chairmen; and T. T. Read, secretary. The report of the commit-tee appointed at the last meeting to consider publica-tion and general policy for the committee was then called for and freely discussed, after which it was unanimously voted to instruct the new chairman to se-cure from the Board of Directors the necessary author-ization for the Committee to recognize as a Division. This action was reported to the Board at its meeting the following night and the authority granted.

Jan 3, 1928

By John T. Galey

The restrictions placed on drilling by the Federal Government, which caused a severe curtailment in activity at the beginning of the year, were relaxed somewhat so as to permit the drilling of one shallow† gas well per 40 acres. New wells numbering 574† were drilled for a combined depth of nearly 1,500,000 It., and of this number 131 were dry holes with a footage of slightly over 375,000. Inside locations account for the majority of these totals and the increasing demand for natural gas would normally have increased the number considerably, but many of the independent operators chose to ask for fewer exceptions to Order M-68 of the Office of Production Management, and consequently to curtail the number of wells drilled. Initial open flow of natural gas developed from all operations§ is over 230 million cu. ft. Nearly 191 million cu. ft. of this volume resulted from the 410 new gas wells drilled to horizons above the Lower Devonian, and the footage drilled in these wells accounts for approximately 93 per cent of the total. Shallow Development Oil.—Thirty oil, wells, with a total initial production of slightly over 152 bbl. and a footage of 50.000, were drilled during the § Including deepening wells previously drilled.

Jan 1, 1943

By John Goheen

CONSIDERABLE work has been done in developing a pyrometer to measure the temperature of molten brasses, bronzes, and aluminum in the crucible. On account of the high melting points and the amount of zinc and sulfurous fumes given off from molten brasses, the conditions are somewhat severe for a thermocouple of standard design; but satisfactory results are obtained with a portable pyrometer, 3 ft. (0.9 m.) of connecting lead wire, and a special 5-ft. nickel-nickel chromium thermocouple, composed of rods ¼ in. (6.35 mm.) in diameter. The lower 12 or 24 in., as desired, may be made detachable so that new tips may be connected at little trouble or expense. The portable instrument need not be of the extreme high-resistance type, as the movable parts of the galvanometer of a lower resistance instrument may be better constructed to withstand the continuous handling such an instrument receives. Platinum-platinum rhodium thermocouples, protected with porcelain and graphite tubes, have been used, but the lag in registering the temperature is too great. It has been found that the range of temperature for various brasses is as follows: Red brasses 2200-2250° F. (1205-1234° C.) Yellow brasses 2250-2400° F. (1234-1318° C.) Bronzes 2300-2550° F. (1260-1400° C.)

Jan 11, 1921

By John T. Galey

The restrictions placed on drilling by the Federal Government, which caused a severe curtailment in activity at the beginning of the year, were relaxed somewhat so as to permit the drilling of one shallow† gas well per 40 acres. New wells numbering 574† were drilled for a combined depth of nearly 1,500,000 It., and of this number 131 were dry holes with a footage of slightly over 375,000. Inside locations account for the majority of these totals and the increasing demand for natural gas would normally have increased the number considerably, but many of the independent operators chose to ask for fewer exceptions to Order M-68 of the Office of Production Management, and consequently to curtail the number of wells drilled. Initial open flow of natural gas developed from all operations§ is over 230 million cu. ft. Nearly 191 million cu. ft. of this volume resulted from the 410 new gas wells drilled to horizons above the Lower Devonian, and the footage drilled in these wells accounts for approximately 93 per cent of the total. Shallow Development Oil.—Thirty oil, wells, with a total initial production of slightly over 152 bbl. and a footage of 50.000, were drilled during the § Including deepening wells previously drilled.

Jan 1, 1943

By R. H. Sweetser

There are probably as many variations of the method for blowing-in blast-furnaces as there are furnace superintendents. That some of these variations are poor practice is shown by the troublesome and sometimes disastrous experiences of many furnace-men, even within the last few years. It is the object of this paper to put on record a blowing-in practice that has gradually developed to the point where the results are sure, safe, and satisfactory; and also to bring into discussion several variations that are questionable. The blowing-in of a modern blast-furnace is one of the greatest of metallurgical operations. On its degree of success depends much of the future life of the lining and the subsequent behavior of the furnace; and it involves possibilities of danger to the men engaged in the work. The objects to be attained are the heating of the interior of the furnace to the high temperature necessary for smelting iron; the starting of the smelting process; and the gradual movement of the stock in its downward course. The most critical points are the placing of the kindling-wood, the " bringing down " of the gas, the closing of the iron-notch, and the first cast. The lighting of the first gas, the opening of the cinder-notch for the first flush, and the running of the first cast are anxious times for the superintendent and the furnace-men. Drying-Out the Furnace. As soon as a furnace-lining is completed it should be thoroughly dried out, whether it is to be blown-in soon or not; and the longer it is dried, the better for the furnace. At least two weeks is desirable; but good results can be had with 10 days of firing. The crudest and least desirable method of drying is to build a wood fire in the bottom of the furnace, throwing the wood in through a tuyere-arch, and using the iron-notch for

Jan 1, 1913

By Robert Y. Grant

This study outlines the history of metal mining in Japan and the characteristics of the industry as they existed from 1925 to 1945. Mining and milling operations are described together with the role of the Japanese Government. A description of post-hostilities conditions and the present state of the industry is included.

Jan 11, 1951

By S. J. Aresco, A. A. Orning

This paper presents a scheme for determination of precision for the various steps in coal sampling, sample preparation, and analysis. It also gives resulting data on 100 American coals from various coal fields covering all ranks from lignite to low-volatile bituminous. The variances of the various steps of the process are studied as a function of the coal preparation, the top size of coal as sampled, and the ash content. To understand the variables that control the overall precision of coal sampling, sample reduction and analysis, there is need for measurement of the variances due to successive steps of the process. The purpose of the present paper is to study these variances as a function of the coal preparation, the top size of the coal as sampled, and the ash content. The sampling data included are from 100 individual preparation plants from various coal fields in the United States and cover all ranks of coal from lignite to low-volatile bituminous; various types of preparation; deep, strip and auger mines; and, in many instances, mixtures from two or more coal beds or types of mines. The collection of data is continuing, but sufficient work has been done to draw some important conclusions. Since the work was done in conjunction with the Bureau of Mines sampling of coal, the time that could be spent at any one preparation plant was limited. This, in turn, limited the number of samples that could be taken for each coal. For this reason, the results from various plants were pooled in blocks. Two major blocking categories were "raw" and "washed!&apos; The raw coals had no preparation other than crushing and/or screening. The washed coals were prepared further by some combination of wet or dry mechanical cleaning. The categories were further divided ac-

Jan 1, 1965