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By AIME AIME

THAT neither the Reconstruction Finance Corp. nor its subsidiary, the Metals Reserve Corp., are in competition with private enterprise was stressed by Charles B. Henderson in an informal talk before the N. Y. Section, A.I.M.E., on Sept. 23. Among other things, the speaker stated that the R.F.C., since its establishment, had authorized loans of $12,000,000, of which over $8,775,000 has actually been distributed. Of this amount, over $6,600,000 has been repaid. None of this money was appropriated by Congress, the sole assistance from that body being the initial authorization of $500,000,000 capital stock.

Jan 1, 1941

By E. R. Kaiser

COAL research during 1942 was directed in an important degree toward the solution of problems of wartime importance. A wider selection of coals for carbonization to meet the increased demand for coke, and the improved utilization of lower-grade coals for boiler fuel were made possible by fundamental studies on cod and ash behavior that had been started several years ago. The coal industry's interest in the work of the various laboratories brightened significantly as results were demonstrated on smokeless combustion in stoves, on stokers without coke trees, and on pulverized firing of forge furnaces. Despite the limitations of priorities and scarcity of materials, the mineral industries building of the West Virginia University was completed and equipped with facilities for research on coal min

Jan 1, 1943

By D. C. Sisti

A technical evaluation of actual performance of the preparation facilities at Beaver Consolidated Coal Co.'s Stinson plant is presented, with special emphasis on sulfur reduction in 1-1/2 x 3/8 in., 3/8 in. x 28 mesh, and 28 mesh x 0 size fractions. Evaluation of the heavy medium section of the plant and the treatment of the 28 mesh x 0 coal is included. Design criteria considered for sizing and selection of equipment required to process 1-3/4 million tpy of raw coal on coals of divergent washability characteristics are summarized.

Jan 1, 1976

THE Institute met on Wednesday evening, May 22d, in the parlor of the Stanton House, Dr. T. Sterry Hunt, President, in the chair. The President delivered an introductory address on the Brown Hematite Deposits of the Great Valley, after which the following papers were read and discussed : Note on the Result of an Experiment with the Wheeler Process of Combining Iron and Steel in the Head of a Rail, by W. E. C. Coxe, of Reading, Pa. On the Jenks Corundum Mine, Macon County, N. C., by Dr. R. W. Raymond, of New York City. On Wednesday afternoon, previous to the opening session, the members who had already arrived in Chattanooga, were taken by the Local Committee to the works of the Roane Iron Company, and Chattanooga Iron Company, and then to the top of Lookout Mountain, where, at the request of the members present, Dr. Hunt described the geological and geographical features of the Chattanooga region, with the magnificent panorama spread out before them as a map. On Thursday morning an excursion was made by steamboat down the Tennessee River as far as Shellmound. Here cars were taken to the coal mines of the Dade Coal Company, where the members were courteously received by Mr. E. B. Wells, the Superintendent. After a trip through the mines the party partook of a collation provided by the company. South Pittsburgh, on the Tennessee River, was next visited, where the Southern States Coal, Iron and Land Company have a large blast-furnace plant in the course of erection. After conducting the party through the works, shops, etc., Mr. James Bowron, the manager, entertained the members with graceful hospitality at dinner. The second session was held on Thursday evening for the transaction of business. The President, Dr. T. Sterry Hunt, appointed Messrs. W. E. C. Coxe, R. H. Richards, and F. J. Slade, scrutineers, to examine the ballots for officers for the ensuing year.

Jan 1, 1879

By Martin A. Moyers

THE nation's effort to win the war speedily is reflected in current trends in coal utilization, as in all other fields of our lives. In all industries, wherever coal is used for the production of heat and power the emphasis is on getting the most useful result with the least expenditure of matt.ria1. In addition to carrying its own share of the load, increased as it is by the demands of war industry, coal has had to fill in for the other fuels, mainly petroleum products, whose distribution from their more distant sources has been crippled by lack of shipping. Thus, the outstanding note in the utilization of coal this year is not the development of new methods of burning or handling coal but the extraordinary job that the industry has done in producing enough coal to serve all needs.

Jan 1, 1943

By John B. Hastings

TEN miles from Hartsel, near Antelope springs, in Park county, Colorado, there is a large area of unconsolidated lake beds, which are interesting because at least a part of the lacustrine sands contains in the aggregate an immense amount of gold. During 1906, one of the arms of this dessicated lake was fairly well prospected with shafts and cuts by an Eastern company to test its value, as favorable amounts of gold had in some instances been found upon it. The claims of the company contain about 5,000 acres of the beds; but this is only a small portion of them, a south branch from a main body, which is at least 7 miles in diameter, with other and very wide lateral gulches, paralleling the one herein described on the east and west. A certain amount of digging and sampling was done in the outside areas; but the result was evidently unsatisfactory, since the work was discontinued. his section of Colorado has not been studied geologically, and the age of the ancient lake is unknown. It is probably Quaternary. I spent two weeks on the ground, in September and October, 1906, but was quite absorbed in the sampling. I looked, however, for terraces on the rim-rock and other evidences of movement and erosion, but did not find anything to denote an earlier age than the Quaternary. The granite rim-rock may be Archean; S. F. Emmons says that some of the granites in central Colorado are as old as that. The rim-rock as observed is a gray quartzose biotite-granite, except a small area in Sections 3 and 34, where it is a felsitic (?) breccia. The breccia is silicified by solfataric action at the corner near Shaft No. 7, in Section 34; but this action is older than the sands and does not extend to them. The shaft averaged 50c. per ton, more than twice as much as the rest.

Jan 5, 1908

By J. J. Lillie

Sublevel stoping was first developed in the Michigan iron mines many years ago. Since that time this method, and modifications with long hole drilling, have been used in a number of non-ferrous mines and have been described in various papers and articles. With a few exceptions, the operations where sublevel methods have been applied are producers of large daily tonnages from ore bodies of considerable size. In selecting mining methods for small properties or relatively small detached ore bodies, sublevel methods often have been overlooked. The method has been used success- fully in relatively small operations at Copper Canyon, Nevada, and, more recently, in mining small ore bodies at Darwin, Calif. As a result of this experience, we believe that a review of the general procedure, the advantages noted, and the results obtained will be of interest to many operators of relatively small mines.

Jan 1, 1949

By Oliver Bowles

PRICES of quartz sold in the United States in 1938 ranged from $1.15 to $36,000 a ton. This startling variation was due simply to the differences between glass sand and rock - crystal, materials that are virtually the same in composition. It illustrates the complexities in qualities, uses, and values of industrial minerals. It is generally stated that mineral deposits are exhaustible resources which can never be replaced when depleted. This statement is no longer true with respect to certain industrial minerals now recovered in increasing quantities from that most inexhaustible of all sources of supply, the ocean. Salt has long been obtained from sea water, particularly on the Pacific Coast, and reference was made a year ago to the large bromine recovery plant at Wilmington, N. C. Now the Westvaco Chlorine Products Corp. is operating a large plant at Newark, Calif., having a capacity sufficient to recover daily from the ocean raw materials that will produce 60 tons of various magnesium products. Lime is used to precipitate the magnesia from salt-water bittern. The products are chiefly magnesium carbonate for chemical uses, periclase and other refractories, and oxychloride cement for flooring.

Jan 1, 1939

By P. E. Fitzgerald

ACIDIZING, as the terns is used in the petroleum production industry, involves the use of hydrochloric acid in predominantly limestone formations, resulting in the lowering of resistance offered to the flow of oil and gas through the oil-bearing formation, usually with resultant increased production. A number of articles have been written on the chemical treatment of oil and gas wells; a bibliography of these works will appear in Volume 123 of the Institute's TRANSACTIONS (1937), and a few other references are appended to this paper.

Jan 1, 1937

By E. C. Houston

The phosphate ores mined in middle Tennessee typically consist of granular rock phosphate particles disseminated in a clayey matrix. In the TVA plant near Columbia, Tenn., the phosphate ore is mined, made into a slurry with the addition of a small amount of sodium hydroxide as dispersant, and treated in a hydroseparator to remove minus 10 micron material. The hydro-separator underflow, comprising a rough concentrate, is transported by pipeline to the plant; the hydro-separator overflow, comprising a tailing, is flocculated by addition of calcium sulphate and is discharged to settling ponds at a rate of about 1400 gpm. Sedimentation in the ponds produces a clarified effluent, which may be recycled for use as process water or discharged to surface drainage. This method of tailing treatment is not entirely satisfactory since poor sedimentation characteristics of the tailing result in poor ultimate utilization of pond storage volume.

Jan 1, 1949

By Claiborne C. Van Zandt

THE heavy postwar demand for Portland Cement has created shortages that are gradually being overcome by increases in plant capacity. In the post-war period, the Lone Star Cement Corp. has expanded several of its existing 15 plants and has built 2 new plants, now in operation, with a third new plant under construction in Brazil, of design somewhat different from that of the two preceding ones. The new domestic plants are located at Lone Star, Va., near Roanoke, and at Maryneal, Tex., near Sweetwater, and went into operation during 1951. Each plant is equipped with two rotary kilns and has an initial capacity of 1,500,000 bbl per year, or 6,000,000 sacks. The total cost of each plant was about $10,500,000, and on this basis $7.00 in 1951 money are required per bbl of annual capacity; at 376 lb per bbl, this corresponds to $37.00 per ton of output. The investment corresponds to approximately $80,000 per hourly-wage earner employed. The purpose of this paper is to describe the most interesting design features of the two new and almost identical Lone Star plants. Why the Dry Process Was Chosen The two new domestic Lone Star mills employ the dry process because: 1-The raw materials at both properties are particularly suitable and can be dried very, readily. 2-The Maryneal, Tex., plant does not have water available for slurry. 3-Very substantial kiln fuel savings can be obtained. 4-Dry raw grinding reduces ball and liner wear and- general maintenance, without any sacrifice in power. Operating costs to date have more than justified the choice of the dry process for these two plants. Raw Materials The chemical composition of Portland Cement raw material after crushing, grinding, and mixing, but before burning, is about as follows: [ ] sometimes tailings from an iron ore concentrating plant. Certain objectionable materials occur in raw mix: magnesia, limited in cement to 5 pct, in excessive amounts; alkalies, as sodium and potassium; phosphorous; and sulphur, generally present in coal and oil. The Roanoke raw, materials are dense limestone and shale. The Maryneal materials are soft limestone and a hard brittle clay that can be handled much like shale. Sand and iron ore are required in small quantities. General Plant Layout and Construction The two plants are so similar that one joint description will cover both, with such exceptions as will be especially indicated. The crushing plant is located in the quarry, and raw material is conveyed by belt to the storage building, where all materials are stored and handled. Fig. 1 identifies the various structures of the Roanoke plant. The large storage building is used for the storing and handling of all materials, including limestone, shale, sand, iron ore, coal, clinker, and gypsum. Directly adjoining the storage building is a structure under a similar arched roof, containing the raw and clinker grinding departments and the electrical substation. The discharge ends of kilns and coolers, and coal or gas burning equipment are also placed at one end of the mill building. The 340ft long kilns extend away from the main buildings to form the long leg of an L, at the end of which is the feeding and kiln dust collecting equipment, and the raw blending silos are conveniently located adjacent to the feed end of the kilns. The machine shop, storeroom, electrical shop, foremen's office, service rooms, and meeting hall are combined in one structure in the center of the plant, and the office and laboratory are close by. The cement silos and packhouse do not have to be tied directly into the manufacturing process and are therefore located at a point convenient to the railroad tracks.

Jan 1, 1952

By R. Gilman Brown

INTRODUCTION. MINES are interesting by reason of what they have done for man, or of what has been done for them by nature. Not all are interesting on both scores. Many profitable mines are commonplace to the geologist; and many presenting unique geological conditions have been sad failures commercially. The Standard group at Bodie has produced in 25 years, $14,500,000, paying $5,000,000 in dividends.' On the other hand, this output has been mined (almost wholly above the 1,000-ft. level) from a system of more than 100 veins, ranging in thickness-from 0.5 in. of "specimen rock" to 30 ft. of clay and quartz; distributed through a zone about 2,000" ft. in width, and representing from three to five distinct periods of formation. This group, therefore, by reason of its industrial record as well as its geological features, may fairly be regarded as doubly interesting. The Bodie district occupies an island of recent (Tertiary) hornblende-andesite, surrounded by a complex of igneous rocks and breccias. It lies at the summit of the eastern foot-hills of the Sierra Nevada mountains, and within the Great Basin, a few miles from its western edge, marked here by Mono lake on the line of the Great Fault. The average elevation of the outcroppings of the veins may be taken at about 5,700 ft. The andesite projects from south to north in a great tongue, 12,000 ft. long and 5,000 ft. wide, reaching an extreme height at the northern end of perhaps 1,000 ft. above the adjoining small canyons. These separate it from the main mass of the foot-hill

Jul 1, 1907

By R. A. Burmeister, P. E. Greene

Two methods for the synthesis and growth of single crystals of B6 P are described: a solution-growth process employing nickel as the solvent, and a vapor-growth process employing BBr3 and pH3 as the reac-tants. Relevant portions of the Ni-B-P phase diagram have been examined and liquidus data are presented for an isobaric section at an equivalent P2 pressure of 3.8 Torr, and an isothertnal section at 1300°C. Solution-growth techniques are described and the purity and crystalline perfection of the resulting material is discussed. Epitaxial growth of BeP on &P substrates has been obtained using the vapor-phase system. Evidence is presented which supports the assignment of the stoichioknetry B6P to boron sub-plwsphide. THE B-P system differs from other III-V systems in that it contains two distinct compounds. The existence of the monophosphide (BP) has been known for some time,' whereas the subphosphide (B6P) was reported only recently.' Both of these compounds are large bandgap semiconductors (Eg = 2.0 ev for BP~ and 3.3 ev for B6P4), and are therefore of interest for optoelectronic applications. The crystal structure of B6P is quite different from those of most semiconductors, being derived from that of a-rhombohedral boron by the incorporation of the two phosphorus atoms in the intericosahedral sites of the a-boron unit cell?76 B6P also exhibits a number of unusual characteristics, including a high degree of chemical inertness, hardness, and high-temperature stability. No information concerning other physical properties is available in the literature. The present study is part of a broader investigation of the preparation and properties of B6P. This paper considers methods of growing single crystals of B6P of suitable size and quality for physical-property measurements. A detailed discussion of the electrical and optical properties of B6P will be given elsewhere.' GENERAL CONSIDERATIONS The method first used to synthesize B6P was the disproportionation of BP' according to the reaction The equilibrium P2 pressures corresponding to this reaction were also determined .'" It is therefore possible, in principle, to apply several of the reactions reported for the synthesis of BP to the synthesis of B6P merely by selecting lower phosphorus pressures or higher temperatures, in accordance with the equilibrium data. Other techniques for the direct synthesis of microcry stalline B8P have also been reported.1°

Jan 1, 1968

By Nicholas J. Grant, John Chipman

A full understanding of the behavior of sulphur in the basic open-hearth process has been delayed by lack of dependable data covering a wide range of slag conditions in the absence of other complicating factors that are likely to be present under operating conditions. It has been generally accepted that strongly basic slags will dissolve more sulphur than will those in which the acidic and basic constituents are more nearly balanced. It has been known that both slag and metal would absorb sulphur from the flame when the sulphur content of the fuel is high. It has been generally believed that manganese assists in the transfer of sulphur from metal to slag. Almost nothing has been known of the effect of temperature upon desulphurization;the data have been conflicting and there has been a tendency to depend rather heavily upon analogy with the better understood desulphurizing reaction of the blast furnace. Many attempts have been made to build up from open-hearth data a satisfactory theory of the chemical reactions involved in the process. That this has been an extremely difficult task is owing to two reasons that have been very generally recognized. The first is the parallel and simultaneous reaction of sulphur transfer between flame and bath. The second is the difficulty of distinguishing between the factors that ultimately limit the transfer from metal to slag—i.e., equilibrium conditions—and those whose influence is only upon the rate of transfer. It has been the object of the work here recounted to study the equilibrium distribution of sulphur between slag and metal in the absence of these complicating factors, with the hope that a better understanding of the equilibria involved would lead to a better control of the over-all process in the open-hearth furnace. A review of the literature on steelmaking reveals almost complete agreement with respect to the paramount importance of lime in promoting desulphurization. In expressing this effect in quantitative terms, however, and in formulating the relationships between the concentrations of other slag components and the desulphurizing power, there is little agreement. For instance, the "basicity" or basic strength of the slag is commonly measured by some kind of ratio of concentration of basic to acidic oxides. Of these, the following have been reviewed by Schenck:20 V radio = % CaO/%SiO, Körber and Oelsen's _ % CaO'. 100/% CaO + % SiO2 where (%CaO') = % CaO- 1.18% P2O5. Herty's B ratio = % CaO - (0.93 . % SO2) - (1.18% P205) Among others there appear the following: 20 References are at the end of the paper.

Jan 1, 1947

By Nicholas J. Grant, John Chipman

A full understanding of the behavior of sulphur in the basic open-hearth process has been delayed by lack of dependable data covering a wide range of slag conditions in the absence of other complicating factors that are likely to be present under operating conditions. It has been generally accepted that strongly basic slags will dissolve more sulphur than will those in which the acidic and basic constituents are more nearly balanced. It has been known that both slag and metal would absorb sulphur from the flame when the sulphur content of the fuel is high. It has been generally believed that manganese assists in the transfer of sulphur from metal to slag. Almost nothing has been known of the effect of temperature upon desulphurization;the data have been conflicting and there has been a tendency to depend rather heavily upon analogy with the better understood desulphurizing reaction of the blast furnace. Many attempts have been made to build up from open-hearth data a satisfactory theory of the chemical reactions involved in the process. That this has been an extremely difficult task is owing to two reasons that have been very generally recognized. The first is the parallel and simultaneous reaction of sulphur transfer between flame and bath. The second is the difficulty of distinguishing between the factors that ultimately limit the transfer from metal to slag—i.e., equilibrium conditions—and those whose influence is only upon the rate of transfer. It has been the object of the work here recounted to study the equilibrium distribution of sulphur between slag and metal in the absence of these complicating factors, with the hope that a better understanding of the equilibria involved would lead to a better control of the over-all process in the open-hearth furnace. A review of the literature on steelmaking reveals almost complete agreement with respect to the paramount importance of lime in promoting desulphurization. In expressing this effect in quantitative terms, however, and in formulating the relationships between the concentrations of other slag components and the desulphurizing power, there is little agreement. For instance, the "basicity" or basic strength of the slag is commonly measured by some kind of ratio of concentration of basic to acidic oxides. Of these, the following have been reviewed by Schenck:20 V radio = % CaO/%SiO, Körber and Oelsen's _ % CaO'. 100/% CaO + % SiO2 where (%CaO') = % CaO- 1.18% P2O5. Herty's B ratio = % CaO - (0.93 . % SO2) - (1.18% P205) Among others there appear the following: 20 References are at the end of the paper.

Jan 1, 1947

By J. E. Pavlick, W. W. Mullins, H. W. Paxton

The growth of nitrogen-austenite during nitriding of large-gvained ferrite between 650" and 800°C has been studied as a functimz oJ time and nitrogen potential of the atmosphere for a variety of alloying elements dissolved in the ferrite. Whereas no preferential grain boundary penetration by aistenite takes place in zone-refined iron, the addition of aboit I zot pct oj' V, Ti, Cr. Si, or A1 produces significant protrusion of austenite down former 0-0 boundaries. This group of elernents also produces ragged y-0 interfaces in the a grains which advance more slozuly than those in zone-refined iron. 1 zut pct of Ni, Co, Mn, or Mo dissolved in ferrite leads to essentially smooth 7-a interfaces, which advance at rates very sinzilar to those in zone-refined iron. The reasons for this effect are not clear. Two possible limiting hypotheses, not necessarily exclusive, are discussed. One involves p.referentia1 grain bozindary diffusion of nitrogen. the other the production of a zone of ferrite, stpersatcirated with respect to nitrogen, from which austenite precipitates helerogeneozisly on the a-a gyain boundaries. In many phase transformations which occur by nu-cleation and diffusion-controlled growth, information on the parameters which control the rates of nuclea-tion and of growth is frequently not quantititative. The present work describes a continuation of efforts to obtain quantitative data on growth rates in systems where thermodynamic and kinetic factors are known independently, and thus where comparison with models of the growth process is possible. The work has been conducted on iron-base systems for two reasons. Firstly, there are several interesting transformations in this system, many of which are of practical importance. Secondly, the information on phase diagrams, activities, and diffusion coefficients is more complete in this system than in any other. These data are still inadequate to check all the effects of alloying elements, but at worst it is possible to make estimates and thus examine order-of-magni-tude agreement with proposed models. It will be necessary to do this in the present work. The problem studied was the growth of nitrogen-austenite in from the surface of large-grained columnar crystals of alloyed ferrite exposed to an NHs/Hz atmosphere. Earlier work by Grozier et al.' had suggested that growth of austenite may occur preferentially along grain boundaries of alloyed ferrite, whereas zone-refined (ZR) iron shows no such effect, Fig. 1. Growth of nitrogen-austenite into single crystals of zone-refined ferrite is planar provided sufficient nu-cleation sites for austenite are present, and is controlled by volume diffusion of nitrogen through the

Jan 1, 1967

By J. R. Lewis

During the past few years there has been considerable interest in the sizing and the preparation of the iron ore fed into blast furnaces. Furnacemen know that proper sizing of ore tends to increase the efficiency of the furnace. It has been shown by Joseph1 and his associates that there is a direct relationship between the porosity of an ore particle and the time required for its reduction in the blast furnace. This relationship may be stated as follows: All other factors remainig constant, the time for reduction of a given sample of ore is inversely propor-tiofid to its porosity. As a consequence, large pieces of very porous ore, say 3 or 4 in. in cross section, will be completely reduced by the time they reach the hot zone just above the tuyeres, while large pieces of dense, nonporous ore may reach the hot zone with their centers unreduced. This means that for the latter complete reduction will be accomplished by the so-called "direct method;" i,e., where carbon reacts directly with the ore. Some recent work by philbrook2 seems to contradict this rule. He found that of two unlike ores he studied, the one with the lower porosity reduced more readily. He explained his results as "possibly due to an apparently greater tendency of the rA, ore (lower porosity) to crack during preliminary dehydration and during reduction." This brings his results in line with the rule stated above. It is not the author's intention to enter into a discussion of the merits of "direct" versus "indirect" reduction. It is enough to Say that, in general, indirect reduction is desirable. For the greatest efficiency, Gruner's theorem3 requires that all reduction in the blast furnace be indirect. Joseph seems to believe this also, because in his recent article on Some Comparisons between Iron Ore, Sinter and Nodules as Blast Furnace Feed4 he concludes that: "In genera', the carbon in blastfurnace coke is used most efficiently when the largest amount of the carbon charged reaches the tuyeres." However, P. V. hlartin,3 in an excellent paper, has shown that some direct reduction may actually increase the efficiency of the furnace; that is, increase its rate of production while maintaining maximum fuel economy. For nonporous ores there is more opportunity to have an excess of direct reduction unless the factors that make for indirect reduction are favored; for instance; the Proper sizing of the Ore particles' Another factor that has an important bearing on the reduction rate, as it is affected by particle size, is the flow of heat into the particle. The ore particle

Jan 1, 1948

By J. R. Lewis

During the past few years there has been considerable interest in the sizing and the preparation of the iron ore fed into blast furnaces. Furnacemen know that proper sizing of ore tends to increase the efficiency of the furnace. It has been shown by Joseph1 and his associates that there is a direct relationship between the porosity of an ore particle and the time required for its reduction in the blast furnace. This relationship may be stated as follows: All other factors remainig constant, the time for reduction of a given sample of ore is inversely propor-tiofid to its porosity. As a consequence, large pieces of very porous ore, say 3 or 4 in. in cross section, will be completely reduced by the time they reach the hot zone just above the tuyeres, while large pieces of dense, nonporous ore may reach the hot zone with their centers unreduced. This means that for the latter complete reduction will be accomplished by the so-called "direct method;" i,e., where carbon reacts directly with the ore. Some recent work by philbrook2 seems to contradict this rule. He found that of two unlike ores he studied, the one with the lower porosity reduced more readily. He explained his results as "possibly due to an apparently greater tendency of the rA, ore (lower porosity) to crack during preliminary dehydration and during reduction." This brings his results in line with the rule stated above. It is not the author's intention to enter into a discussion of the merits of "direct" versus "indirect" reduction. It is enough to Say that, in general, indirect reduction is desirable. For the greatest efficiency, Gruner's theorem3 requires that all reduction in the blast furnace be indirect. Joseph seems to believe this also, because in his recent article on Some Comparisons between Iron Ore, Sinter and Nodules as Blast Furnace Feed4 he concludes that: "In genera', the carbon in blastfurnace coke is used most efficiently when the largest amount of the carbon charged reaches the tuyeres." However, P. V. hlartin,3 in an excellent paper, has shown that some direct reduction may actually increase the efficiency of the furnace; that is, increase its rate of production while maintaining maximum fuel economy. For nonporous ores there is more opportunity to have an excess of direct reduction unless the factors that make for indirect reduction are favored; for instance; the Proper sizing of the Ore particles' Another factor that has an important bearing on the reduction rate, as it is affected by particle size, is the flow of heat into the particle. The ore particle

Jan 1, 1948

By Carl F. Floe, John Chipman

THE system molten copper-oxygen-sulphur is of interest from both the practical and theoretical standpoints; practically, because oxygen and sulphur play an important role in the commercial production of copper, and theoretically because it offers a chance to study the reaction between an oxide gas, SO2, and a molten metal. Reactions of this type, such as that between CO or CO2 and molten iron, are important in many metallurgical operations. Again, the determination of any gas-metal equilibrium is of theoretical interest and value insofar as it contributes to the general development of the laws for solution of gases in metals. This problem is being given an increasing amount of attention in modern metallurgy. This paper is the first of a series and presents the results of a determination of the solubility of sulphur dioxide in molten copper at temperatures from 1100° to 1500°C., and pressures from about 20 mm. of mercury to somewhat above atmospheric. REVIEW OF PREVIOUS WORK The solubility of gases in most liquids has been found to obey Henry's law, which states that for a fixed temperature the amount of gas dissolved is directly proportional to the pressure. However this law does not hold for liquid metals. Instead, it appears that for many gases, particularly the simple diatomic ones such as 02, N2 and H2, the amount dissolved in liquid metals is directly proportional to the square root of the pressure. This is known as Sieverts' law. It may be recognized as a special case of Henry's law, which applies when the solute gas is dissociated into atoms or when it reacts with the solvent metal to form solute molecules containing single atoms of the gaseous elements, as, for example: [(MG) l 2M +G2 = 2MG K = Ma X Pa, [I]] which, if the solubility is not too high and the concentration of metal therefore nearly constant, can be simplified to: [MG = Kl Pa,[2]] Following the same reasoning, it would be expected that the solubility of SO2 in copper would be proportional to the cube root of the pressure, the reaction being as follows: [6Cu + SO2 = Cu2S + 2Cu20[3] K _ Cu2S X (Cu20)2 (Cu)6(Pso2)[4]] or, neglecting the change in metal concentration and considering that the concentrations of sulphur and oxygen are both proportional to the volume V of gas absorbed: [8 =KI = Pte, or VSO2= K2 '~/PeO, [S]]

Jan 1, 1941

By B. N. Das, H. E. LaBelle, G. A. Wolf

ZnxHg1-xTe and GUPxAS1-x crystals have been grown from solution by a traveling heater method (THM). In a floating zone type fashion a solution zone sandwich of liquidus composition is made to migrate through feed material of solidus composition by a slow-speed movement of <0.25 mm per hr of the total charge through a stationary radiation or rf heater. ZnxHg1-xTe of composition 0 < x < 0.3 and GUPxAS1-x of composition 0.5 < x < 0.7 have thus been grown from their solution in liquid tellurium and gallium, respectively. A simplified analysis of heat and material transport is given. In this method, Proper adjustment of the temperature distribution along the liquid solution zone axis eliminates instability of the crystal growth front and constitutional supercooling. 1) ZnxHg1—xTe: The solid-solution telluride was grown in sealed quartz tubes at a temperature of 500 to 650°C. For first Preparations mechanical mixtures SINGLE crystals of solid solutions of III-V and II-VI compounds have been grown by various techniques from the melt, from the gaseous phase, or from solutions in of ZnTe and HgTe were used. X-ray determinations showed the resulting crystals to be homogeneous throughout their entire length, except for the end sections. The homogeneity is greatly improved by reusing the ingots obtained from first Preparations as feed material in subsequent crystal growth runs. Ingots of up to 4.5 cm have thus been obtained. 2) GaPxAs1-x: Crystals were grown in a EN crucible at a temperature of 1050°C. For first Preparation a mechanical mixture of Gap and GaAs was cemented together by a minimum amount of liquid gallium through "wet" grinding of Gap and GaAs crystals in the liquid metal and subsequent exuding of excess gallium by compacting of the charge in the EN crucible. Electron microprobe measurements using P-Ka and As-Ka radiation showed uniformity over a length of 0.4 cm. Properties of the various Preparations are described. liquid metals.&apos;-&apos; Their growth from the melt by passing a liquid zone of pseudobinary liquidus composition through a solid rod of solidus composition is generally a convenient method of growth of single crystals of solid solutions of homogeneous composition. This method loses much of its usefulness, however, if the melting point or the vapor pressure of the solid solution is high. In the case of a compound having a high melting

Jan 1, 1969