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By W. A. Ver Wiebe

It is becoming increasingly apparent that the State of Kansas contains one of the largest reserve areas for oil exploration in the United States. During the year 1936 no less than 54 new oil pools were discovered by drilling. In addition, seven gas pools were found, which may develop into oil pools when deeper horizons are tested. Several old pools increased their reserves when production was found in lower strata. The data presented in Table 2 indicate that nearly 2000 wells were drilled in the state during 1936. Of these more than 1214 found commercial quantities of oil and at least 61 found marketable quantities of gas. The data are conservative because complete results on drilling are not available for the eastern part of the state. Ellis, Rice and Russell Counties share honors with a total of 10 new pools in each. Barton County is prominent with six pools; while those counties claiming fewer new pools are Clark, Ellsworth, Harvey, McPherson, Ness, Pawnee, Rooks, Stafford and Trego. Important additions to our gas reserves were found in Finney and Haskell Counties, which are north of the extensive Hugoton gas area and may some day be part of it. At the close of the year there were 17,317 wells in the state rating as producers. By far the larger share (14,000) were classed as strippers and allowed to flow 100 per cent of their potential capacity, thus accounting for 33,500 bbl. a day. The remaining wells, capable of producing from 15 up to over 6000 bbl. per day, were limited in output according to these amounts. The largest wells having a potential of from 3000 to 7000 were allowed to flow from 2 to 3½ per cent of their official potential capacity. The percentage rises until wells of 15 to 20-bbl. capacity have a rating of slightly over 83. On the basis of these calculations the total potential capacity of all wells was 1,667,814 bbl., and the daily amount allowed was 175,851. Nine of the pools most recently opened were still unable to market their oil and were classified as "shut-in" pools. Total production for the state for 1936 was somewhat over 58 million barrels. Striking Geological Data Some interesting geological data were uncovered by deep drilling during the year. The most remarkable bit of information is the discovery

Jan 1, 1937

By P. W. George, G. A. Hellstrand

In 1915, H. A. Guess, Vice President of American Smelting & Refining Co., in charge of its Mining Department, learned that the Anglo-Newfoundland Development Co., Ltd., a pulpwood and paper-mill enterprise, had found upon its large concession in Newfoundland, and had opened up by shaft to the third level and some drifting, a lenticular orebody indicating about 100,000 tons, as an extremely fine-grained sulfide ore, averaging about 0.05 oz. Au, 4 oz. Ag, 1.5 per cent Cu, 10 per cent Pb, 18 per cent Zn; and that having sent parcels of this ore to Minerals Separation, Ltd., and various other metallurgical testing concerns without obtaining any success in commercial separations thereof, had discontinued work thereon and let the workings fill. Mr. Guess wrote to the general manager of that company and obtained a few hundred pounds of the typical ore, which he sent to his company's metallurgical testing laboratory at Flat River, Mo., outlining various flotation tests desired thereon, in an endeavor to obtain separation into a commercial lead concentrate and a zinc concentrate. But the art of flotation had not then progressed far enough to treat such ore, the galena and zinc blende being so fine grained that grinding to about 300 mesh was required to release the mineral particles in their gangue. Mr. Guess had flotation and other tests continued upon this ore from time to time with whatever new reagents and flotation devices were evolved as time went on, and finally, in 1925, he succeeded in effecting in his company's testing plant, then at Wallace, Idaho, separations into lead concentrates and zinc concentrates of satisfactory commercial grade. Mr. Guess then proceeded to unwater, examine and sample the property and made with the owners a partnership operating agreement upon the mine itself and a considerable area surrounding it, and in the early summer of 1926 began to prospect for additional orebodies, utilizing for such prospecting geophysical methods under the direction of Hans Lundberg, methods which up to that time had been little used in mining in the western hemisphere. This geophysical work found two large flat-lying orebodies of a type precisely similar to the smaller body of the original discovery. The larger orebody, some 3500 ft. west of the original

Jan 1, 1935

By Leonard D. Jaffe

In recent years, the advantages of tempered martensite as a microstructure for steel parts have been well established. For parts that must not fracture brittlely when loaded at high rates, at low temperatures, or under conditions of combined stress, tempered martensite is especially desirable. One of the factors that determine whether a steel part will have a martensitic structure after heat treatment is the hardenability of the steel. Despite the large amount of recent research, there are still many unsettled basic questions concerning hardenability and its relation to chemical composition, and, indeed, considerable disagreement among investigators in the field. Much of the uncertainty that beclouds the existing knowledge of hardenability arises from the fact that hardenability is still a wholly empirical concept, and has not been quantitatively related to the more fundamental knowledge of isothermal decomposition of austenite. Hardenability is, essentiaily, a measure of the time required for small percentages of austenite to decompose, during continuous cooling, to pearlite, bainite, proeutectoid ferrite, or proeutec-toid carbide. In the practical heat-treat- ment of steel, also, the decomposition of austenite is usually not isothermal but rather during cooling, or, in general, is not at a single constant temperature. Thus, both hardenability and practical heat treatment involve anisothermal decomposition of austenite. In a previous publication1 the author and his collaborators outlined the principles that govern the relations between isothermal and anisothermal decomposition of austenite, and reviewed the experimental information available in 1945. To avoid repetition, familiarity with that article (Paper I) will be assumed, and attention given primarily to work carried out or published since 1945. The method generally employed was explained in Paper I: anisothermal transformation is studied through investigation of the effect of holding austenite at one temperature upon its subsequent decomposition at another temperature. Both temperatures are below the stability range of the austenite. This paper is confined to studies in which only a small amount of transformation occurred at the first temperature. This is the only case of importance in practical heat treatment when an essentially martensitic structure is sought. Materials and Procedure It was necessary to use different steels for the studies involving proeutectoid ferrite and for those involving proeutectoid carbide, beeause the two constituents have not been found to form in the same steel. Several steels were tried and rejected

Jan 1, 1949

By Leonard D. Jaffe

In recent years, the advantages of tempered martensite as a microstructure for steel parts have been well established. For parts that must not fracture brittlely when loaded at high rates, at low temperatures, or under conditions of combined stress, tempered martensite is especially desirable. One of the factors that determine whether a steel part will have a martensitic structure after heat treatment is the hardenability of the steel. Despite the large amount of recent research, there are still many unsettled basic questions concerning hardenability and its relation to chemical composition, and, indeed, considerable disagreement among investigators in the field. Much of the uncertainty that beclouds the existing knowledge of hardenability arises from the fact that hardenability is still a wholly empirical concept, and has not been quantitatively related to the more fundamental knowledge of isothermal decomposition of austenite. Hardenability is, essentiaily, a measure of the time required for small percentages of austenite to decompose, during continuous cooling, to pearlite, bainite, proeutectoid ferrite, or proeutec-toid carbide. In the practical heat-treat- ment of steel, also, the decomposition of austenite is usually not isothermal but rather during cooling, or, in general, is not at a single constant temperature. Thus, both hardenability and practical heat treatment involve anisothermal decomposition of austenite. In a previous publication1 the author and his collaborators outlined the principles that govern the relations between isothermal and anisothermal decomposition of austenite, and reviewed the experimental information available in 1945. To avoid repetition, familiarity with that article (Paper I) will be assumed, and attention given primarily to work carried out or published since 1945. The method generally employed was explained in Paper I: anisothermal transformation is studied through investigation of the effect of holding austenite at one temperature upon its subsequent decomposition at another temperature. Both temperatures are below the stability range of the austenite. This paper is confined to studies in which only a small amount of transformation occurred at the first temperature. This is the only case of importance in practical heat treatment when an essentially martensitic structure is sought. Materials and Procedure It was necessary to use different steels for the studies involving proeutectoid ferrite and for those involving proeutectoid carbide, beeause the two constituents have not been found to form in the same steel. Several steels were tried and rejected

Jan 1, 1949

By H. H. Power, Charles R. Houssiere

THE development of effective and dependable methods for drilling through the so-called "heaving-shale" horizons, particularly in the Gulf Coast area, is believed to comprise a major contribution to drilling technology, and to the task of finding and developing our undiscovered oil pools. Many mechanical remedies have been proposed and are in use in troublesome areas for combating heaving shale. However, in conducting a research program it was concluded that the physical and chemical properties of shales should be investigated, and the effect of added chemicals on such properties determined. As a preliminary step, the effect of chemicals on bentonitic suspensions was determined in accordance with recent contributions in the field of ceramics. The most plausible theoretical explanations for the behavior of the clay minerals involved are offered in the paper that follows. It is hoped that subsequent investigation of actual shale from troublesome wells will be aided by the initial work done on bentonitic suspensions of known composition. INTRODUCTION Formations variously designated as "heaving shale," "sloughing shale" and "caving shale" impede and may even preclude drilling of oil wells, particularly in certain parts of the Gulf Coast. In a previous paper1 it has been stated that the development of effective and dependable methods for drilling through these troublesome beds is believed to comprise a major contribution to drilling technology, and to the task of finding and developing our undiscovered oil pools. Since the attack on the heaving-shale problem by mechanical means was principally a matter of field investigation, it was concluded that a research program should be concerned with the physical and chemical properties of heaving shales, and the effect of added chemicals on such properties. It was realized that a study of shales required an advanced knowledge of the behavior of the individual clay minerals. A thorough review of the literature led the authors to the conclusion that very recent contributions2.3 in the field of ceramics furnished the most plausible theoretical explanations for the behavior of clay minerals. Accordingly, these fundamental ideas will be used in an attempt to explain the behavior of more complex systems whose composition and replaceable ions are known. In order to obtain comparable results it was deemed important to select an easily procurable clay of uniform characteristics. Accordingly, Wyoming bentonite, which is marketed under the name of "Volclay,"* was used for the preliminary investigations. The chemical analysis reported by the distribution is given as follows:

Jan 1, 1941

By R. C. Buehl, J. P. Morris

ACTIVITY values for sulphur dissolved in liquid iron and slags as functions of composition and temperature are needed in applying thermodynamics to sulphur-control problems in iron- and ' steel-making. The purpose of this investigation was to determine the effect of carbon on the activity of sulphur in the metal phase. The method employed was the same as that used in an earlier investigation' concerning the effect of silicon on sulphur activity in liquid iron. A study was made of the conditions of equilibrium in the reaction between hydrogen gas and sulphur dissolved in iron-carbon alloys. The chemical equation for this reaction can be written as follows: S (in liquid Fe-C alloy) + H2 (gas) = H2S (gas). It was found that the activity coefficient of sulphur in liquid iron increases as the carbon content increases. At 2.3 pct carbon and 1600 °C, the activity coefficient of sulphur is twice its value in carbon-free iron, and at carbon saturation it is more than six times as great. The effect of temperature on sulphur activity was found to be small. Previous work on the reaction between hydrogen gas and sulphur dissolved in liquid iron has been reported by several investigators2,³,4 but only recently have studies been made of the effect of alloying elements. Silicon1 is known to have a pronounced influence on the activity of sulphur in iron, its effect being similar to that shown by carbon as described in the present report. Kitchener, Bockris, and Liber-man5 recently have published a preliminary report of their work on the effect of carbon on sulphur activity in iron. Their experiments were made at 1570°C and carbon saturation in the melt. Under these conditions they found that the activity coefficient of sulphur was approximately doubled by the presence of carbon. This is a much smaller effect than that found in the present work. Experimental Method: The apparatus and procedure were essentially the same as those used in the earlier investigation of the effect of silicon on sulphur activity.' Briefly, the method was as follows: A molten iron-carbon alloy was brought to equilibrium at constant temperature with a mixture of H2 and H2S of constant composition by bubbling the gas through the metal. Samples of the melt were

Jan 1, 1951

By T. Cameron Kenney

INTRODUCTION Whereas the design of rock slopes in open-pit mines is done largely by mining engineers and geologists, the design of slopes in overburden at this point in time is a problem for which civil engineers or geotechnical engineers are best prepared to deal. The reasons for this situation are to be found in the educational curricula and the technical journals of the two groups, where soil mechanics has received little attention by mining engineers and geologists, and rock mechanics has similarly received little attention by civil engineers. In ten years' time this paper will hopefully be considered by young mining engineers to be a repeat of the material that they studied at university. However, even in ten years time I believe that the civil (or geotechnical) engineers will be extensively used as consultants on overburden- slope problems of open pit mines because mining companies will find this more expedient than maintaining their own geotechnical staff, special field equipment and special testing laboratories. For this reason, the purpose of this paper is not to condense several university soil mechanics courses into a twenty-page text for mining engineers and geologists. Rather, the purpose of the paper is to offer a general explanation of various factors affecting slope stability so that mining engineers and geologists will have a better understanding of the behaviour of overburden soils in slopes. A great deal has been written in soil mechanics literature on the subject of slope stability. No attempt will be made to reference all this material but rather only a selected number of references will be cited. Excellent general treatments of the subject of stability of overburden slopes are available (1,2,3,4). Further information of a more specialized nature is to be found in such publications as the Journal of the Soil Mechanics and Foundation Division of the American Society of Civil Engineers, Geotechnique (printed by the Institution of Civil Engineers, England), Canadian Geotechnical Journal, and the proceedings of the conferences of the International Society for Soil Mechanics and Foundation Engineering. FACTORS INFLUENCING SLOPE STABILITY There are two general scales of slope-stability problems, gross stability and local stability. Gross stability refers to large volumes of soil, and gross instability would involve large rotational-type shear failures. Local stability refers to something much smaller and examples

Jan 1, 1972

By H. F. Yancey, M. R. Geer, Franklin T. Davis

Coke with low phosphorus content is required by some of the electrometallurgical and chemical plants recently attracted to the Pacific Northwest by the hydroelectric power available from Bonneville and Grand Coulee dams. Shipping such coke into the area from eastern points involves a high freight charge, and during wartime consumes precious rail and ship-bottom space, so it is highly desirable to produce coke from the coking coals of Washington to meet the requirements of these industries. Although coke has been made from Washington coals since 1884, little has been known about their phosphorus contents or about the extent to which phosphorus could be reduced by cleaning, An investigation was undertaken, therefore, to determine the manner in which phosphorus occurs in the coking coals of Washington and its amenability to removal by ordinary coal-washing methods. Previous Work Phosphorus is a deleterious element in coke used for numerous metallurgical processes, including the production of pig iron, yet comparatively little published information is available on the occurrence and elimination of phosphorus in any of the coals of this country. A variation from 0.009 to 0.062 per cent phosphorus in various horizons of the Pittsburgh bed in the Connellsville region of Pennsylania has been reported,' and a reduction in phosphorus content from 0.020 per cent in the raw coal to 0.018 per cent in the washed coal was obtained in washing coal from the same bed in the Pittsburgh area;2 the latter figures represent average analyses for a year's operation of the washery on about 800,000 tons of coal. A reduction in phosphorus content from 0.018 to 0.011 per cent in washing coal from the Pittsburgh bed at another washery was observed, and the same report provides data on the phosphorus reduction obtained by separating 10 other coals on a bath of 1.35 specific gravity.3 European investigators have been especially active in correlating phosphorus content with petrographic analysis; fusain and durain generally contain the highest percentage of phosphorus, but this relationship is not universal.4 Some of these investigators have found that phosphorus is removed in the coal-washing process,5 but others have observed that the clean coal contained as much or even more phosphorus than the raw coal.'

Jan 1, 1944

By A. E. Martin, Gerhard Derge

IF the molecular constitution of molten slags were better known, the nature of chemical reactions in slags and between slags and metals could be better understood and as a consequence might be better controlled. Constitutional information can be obtained by studies on either the molten or the solidified slags. Valuable as the studies on solidified slags admittedly are for many purposes, especially as control methods in steelmaking, they are always of questionable value in giving information on the molecular constitution of liquid slags. However, the characteristics of molten slags such as viscosity, rates of diffusion, and electrical conductivity can be determined experimentally and interpreted along with other knowledge on slag-metal and slag-gas reactions so as to provide direct information on liquid slags. Metallurgists are accustomed to regard reactions in molten slags as involving only neutral molecules, whereas it is quite possible that ionic constituents are actually involved. For example, the dissociation of calcium silicate usually is represented as Ca2SiO4 = 2CaO + SiO2 although a reasonable alternative would be to write Ca2SiO4 = 2Ca+2 + Si04-4 Such ionic dissociation has been suggested frequently without adequate experimental proof. This paper deals especially with electrical conductivity measurements on slags of the blast-furnace type. These measurements were made to determine whether or not slags are ionized and, if so, to provide a qualitative estimate of the extent of ionization. Electrolysis experiments that indicate the identity of the ions present are also reported. Since the presence of ions has not been considered carefully in modern slag studies, the relevant literature will be reviewed. REVIEW of LITERATURE In 1906 Aiken1 obtained a patent for a continuous process of producing iron electrolytically by passing a direct current through a bath of FeO-SiO2 to which iron oxide was added periodically to maintain a uniform concentration. The patent also included the addition of CaO and MgO to the bath to lower its melting point. The silicate melts involved were thus in the same system as basic open-hearth slags but with higher FeO and lower CaO contents. Electrical conductivity measurements were made on some molten silicates by Doelter2 in 1907. Natural silicates, such as

Jan 1, 1943

By J. R. Long, E. L. Anderson, R. S. Dean, F. S. Wartman

TITANIUM has been estimated to comprise about 0.65 per cent of the earth's crust and ranks fourth in abundance among the metallic elements suitable for engineering uses. In spite of this, applications of titanium for structural purposes have not as yet been developed. Its commercial exploitation has been largely confined to the chemical industries and the production of paints and pigments; no doubt because of the difficulties that lie in the way of preparing the pure ductile metal. Published reports, however, indicate that ductile titanium can be prepared and possesses some unique properties. This, together with the occurrence in this country of several important titaniferous deposits, has led the Bureau of Mines to investigate processes for the production of metallic titanium, 'methods required for its fabrication, and the properties that may be produced in this interesting metal. METHODS OF PREPARING METALLIC TITANIUM Many early investigators claimed to have isolated metallic titanium; but in the light of present knowledge, it seems that they really had produced various mixtures of carbides and nitrides that have a metallic appearance but are brittle, hard, and unworkable. The first metallic titanium pure enough to be malleable when cold was produced by Hunter1 in the early part of the twentieth century. Kroll,2 van Arkel,3 and Fast,4 subsequently confirmed the facts that pure titanium is a ductile metal and that small amounts of impurities were responsible for previous reports of brittleness. When heated, titanium reacts chemically with various gases, such as hydrogen, oxygen and nitrogen; if the volume of gas thus absorbed is too great, the metal becomes brittle and unworkable. The principal difficulty in making ductile titanium is prevention of such contamination, and the success of a given process may be judged by the completeness with which it solves this difficulty in a practical manner. Of the gases mentioned, hydrogen is the least objectionable, since its absorption by the metal is completely reversible and, although dimensional changes occur and absorption of hydrogen embrittles the metal, the gas may be removed readily by heating in a high vacuum for a short time. On the other hand, the absorption of oxygen or nitrogen results in the formation of permanent 'solid solutions of the oxide and nitride, which cannot be decomposed by the strongest reducing agents2 with sufficient completeness to restore the inherent ductility of the metal. Because of

Jan 1, 1946

By M. R. Geer, Franklin T. Davis, H. F. Yancey

Coke with low phosphorus content is required by some of the electrometallurgical and chemical plants recently attracted to the Pacific Northwest by the hydroelectric power available from Bonneville and Grand Coulee dams. Shipping such coke into the area from eastern points involves a high freight charge, and during wartime consumes precious rail and ship-bottom space, so it is highly desirable to produce coke from the coking coals of Washington to meet the requirements of these industries. Although coke has been made from Washington coals since 1884, little has been known about their phosphorus contents or about the extent to which phosphorus could be reduced by cleaning, An investigation was undertaken, therefore, to determine the manner in which phosphorus occurs in the coking coals of Washington and its amenability to removal by ordinary coal-washing methods. Previous Work Phosphorus is a deleterious element in coke used for numerous metallurgical processes, including the production of pig iron, yet comparatively little published information is available on the occurrence and elimination of phosphorus in any of the coals of this country. A variation from 0.009 to 0.062 per cent phosphorus in various horizons of the Pittsburgh bed in the Connellsville region of Pennsylania has been reported,' and a reduction in phosphorus content from 0.020 per cent in the raw coal to 0.018 per cent in the washed coal was obtained in washing coal from the same bed in the Pittsburgh area;2 the latter figures represent average analyses for a year's operation of the washery on about 800,000 tons of coal. A reduction in phosphorus content from 0.018 to 0.011 per cent in washing coal from the Pittsburgh bed at another washery was observed, and the same report provides data on the phosphorus reduction obtained by separating 10 other coals on a bath of 1.35 specific gravity.3 European investigators have been especially active in correlating phosphorus content with petrographic analysis; fusain and durain generally contain the highest percentage of phosphorus, but this relationship is not universal.4 Some of these investigators have found that phosphorus is removed in the coal-washing process,5 but others have observed that the clean coal contained as much or even more phosphorus than the raw coal.'

Jan 1, 1944

By A. H. Lindley, R. Shorr, Frazier M. Stewart, F. Crerie

The mineral industry, so important to industrial development, faces a major challenge in creating the most effective financial structure to provide funds essential for seeking, evaluating, developing, and extracting minerals. The acquisition of funds for mineral development and plant erection do not differ greatly from fund-raising in nonmineral ventures because risks are essentially comparable. High-risk exploration funds, however, are more difficult for the mineral industry to acquire. With the world's ever-increasing appetite for minerals, the internally generated cash of major oil and mining companies cannot be expected solely to maintain the world's mineral supply. The augmented costs, risks, and difficulties of exploration have been shared increasingly by the smaller independent operator and by private and public participation drilling programs within the petroleum industry over the past 30 years. Only recently has the mining industry awakened to the need for utilizing exploration and development funds derived from sources other than established mining and banking circles. Almost from its inception, the oil industry was forced to drill deep holes through overburden without the aid of a mineral "outcropping" which required geological, and in subsequent years, geophysical interpretation. The poorly financed, nontechnical prospector, who depended on a mineral outcrop, was not to play an important role in oil exploration as he did in mining. Because of the high cost of drilling and the demands for technical judgment to locate an exploration drill hole, corporate and sophisticated private funds generally financed oil discoveries. When external funds were subsequently required, these financially sophisticated explorers would turn to the banking community from which came numerous ingenious innovations, taking cognizance of existing tax laws. Like the oil explorer, the miner is now faced with probing below the surface, relying solely on regional geology and geophysical anomalies. The day is gone, for practical purposes, when the prospector discovers a deposit from a mineral outcrop. There is little doubt that the mining industry will now follow the course taken by the petroleum industry in acquiring external funds if it is to meet the future raw material requirements of the world. The oil industry has been able to attract bank funds more readily than the mining industry after a mineral discovery has been made because: (1) with few exceptions, an oil discovery can be placed into commercial production and will generate cash at much less expense and time than a mine; and (2) generally, costs of oil production, the value

Jan 1, 1976

By David L. Riley

Organization The Foundling Years - 1901-1921 Two events that occurred in the decade of the 1870's have had far- reaching effects upon the petroleum industry in the U. S. and formed a basis for the birth and growth of the petroleum engineering profession. In 187 1 a group of mining engineers banded together to form the American Institute of Mining Engineers "to promote the arts and sciences connected with the economic production of the useful minerals and metals and the welfare of those employed in these industries by all lawful means". Although it was to be 30 years before an event in Jefferson County, Tex., would cause petroleum to come into prominence as the world's principal source of energy, the founding of AIME provided an organization through which the application of engineering to the recovery of petroleum and natural gas could be developed. In 1875, a Pennsylvania judge who was called upon to make a decision for which there was no precedent reasoned that oil and gas were like wild game - they belong to the man who can reduce them to possession. His decision sired the "rule of capture", which stated that a landowner possesses the oil produced from his well, even though it might have come from beneath his neighbor's land. This interpretation prevailed for more than half a century, during which time gold-rush tactics were employed in the drilling and production of many oil fields in the U. S. The resulting overproduction and tremendous waste led to a virtual economic collapse of the U. S. petroleum industry by the early 1930's. To bring these malpractices under orderly control, proration and conservation policies were developed, and petroleum engineering became the medium through which they were devised and implemented. At the turn of the 20th Century, more than 90 percent of this country's oil production came from the East, but the picture changed with dramatic suddenness on Jan. 10, 1901. Captain Anthony F. Lucas, an Austrian mining engineer, had noticed concentrations of oil and gas near salt domes during mining operations on the Louisiana Gulf Coast. In 1899 he leased a low mound near Beaumont, Tex., began drilling, and after almost 2 years of intermittent operations, brought in the famous "Lucas Gusher"

Jan 1, 1971

By W. G. Woolf, E. R. Crutcher

The electrolytic zinc plant of the Sullivan Mining Co. is in Government Gulch, at Silver King, Shoshone County, Idaho, in the Coeur d'Alene mining district, about one mile from the Bunker Hill smelter and about three miles from Kellogg. The Sullivan Mining Co., which owns both the zinc plant and the Star mine, is itself owned jointly by the Bunker Hill & Sullivan Mining & Concentrating Co, and the Hecla Mining Company. The Tainton high-density, high-acid process is used at this plant, therefore some parts of its flowsheet differ markedly from those of electrolytic plants using the low-density process. While it is a custom plant and has treated a variety of zinc concentrates originating from various sources in a number of states, it has obtained its main supply of zinc concentrates chiefly from the zinc-bearing ores of the Coeur d'A1ene mining district, of which the principal important sources have been the Bunker Hill and Star mines. Thus the main feed has been zinc concentrates obtained from complex lead-zinc-silver ores. For the year of 1935 the concentrates had the following composition: water, 9.5 per cent; Zn, 50.6; Pb, 3.3; Fe, 9.4; S, 31.0; Cu, 0.2; insoluble, 2.9. Flowsheet The concentrates are delivered to the plant in railroad cars, which discharge into storage bins directly under the track. Bottom-dump cars are dropped directly into the bins while a slip scraper, pulled by an air tugger hoist, is used to empty box cars. There are five storage bins for concentrates, each of approximately 300 tons capacity. At the bottom of each bin there are individual belt feeders that discharge onto a common conveyor belt, which in turn discharges to another belt that carries the concentrate onto a weightometer belt for weighing. Immediately after the weighing, the crushed oversize return from the roasters is added to the load on the belt and then the ground-up sweepings, lumps and roaster cleanings. An electromagnet at the end of this conveyor removes tramp iron from the feed. The belt discharges to a set of 30 by 12-in. rolls, which break up lumps or frozen chunks of concentrate, etc. Beneath the rolls there is a screw conveyor, which conveys the roll discharge to a

Jan 1, 1937

By E. L. Anderson, J. R. Long, R. S. Dean, F. S. Wartman

Titanium has been estimated to comprise about 0.65 per cent of the earth's crust and ranks fourth in abundance among the metallic elements suitable for engineering uses. In spite of this, applications of titanium for structural purposes have not as yet been developed. Its commercial exploitation has been largely confined to the chemical industries and the production of paints and pigments; no doubt because of the difficulties that lie in the way of preparing the pure ductile metal. Published reports, however, indicate that ductile titanium can be prepared and possesses some unique properties. This, together with the occurrence in this country of several important titaniferous deposits, has led the Bureau of Mines to investigate processes for the production of metallic titanium, methods required for its fabrication, and the properties that may be produced in this interesting metal. Methods of Preparing Metallic Titanium Many early investigators claimed to have isolated metallic titanium; but in the light of present knowledge, it seems that they really had produced various mixtures of carbides and nitrides that have a metallic appearance but are brittle, hard, and unworkable. The first metallic titanium pure enough to be malleable when cold was produced by Hunter1 in the early part of the twentieth century. Kroll,~ van Arkel,~ and Fast,4 subsequently confirmed the facts that pure titanium is a. ductile metal and that small amounts of impurities were responsible for previous reports of brittleness. When heated, titanium reacts chemically with various gases, such as hydrogen, oxygen and nitrogen; if the volume of gas thus absorbed is too great, the metal becomes brittle and unworkable. The principal difficulty in making ductile titanium is prevention of such contamination, and the success of a given process may be judged by the completeness with which it solves this difficulty in a practical manner. Of the gases mentioned, hydrogen is the least objectionable, since its absorption by the metal is completely reversible and, although dimensional changes occur and absorption of hydrogen embrittles the metal, the gas may be removed readily by heating in a high vacuum for a short time. On the other hand, the absorption of oxygen or nitrogen results in the formation of permanent solid solutions of the oxide and nitride, which cannot be decomposed by the strongest reducing agentsz with sufticient completeness to restore the inherent ductility of the metal. Because of

Jan 1, 1946

By J. R. Long, E. L. Anderson, R. S. Dean, F. S. Wartman

Titanium has been estimated to comprise about 0.65 per cent of the earth's crust and ranks fourth in abundance among the metallic elements suitable for engineering uses. In spite of this, applications of titanium for structural purposes have not as yet been developed. Its commercial exploitation has been largely confined to the chemical industries and the production of paints and pigments; no doubt because of the difficulties that lie in the way of preparing the pure ductile metal. Published reports, however, indicate that ductile titanium can be prepared and possesses some unique properties. This, together with the occurrence in this country of several important titaniferous deposits, has led the Bureau of Mines to investigate processes for the production of metallic titanium, methods required for its fabrication, and the properties that may be produced in this interesting metal. Methods of Preparing Metallic Titanium Many early investigators claimed to have isolated metallic titanium; but in the light of present knowledge, it seems that they really had produced various mixtures of carbides and nitrides that have a metallic appearance but are brittle, hard, and unworkable. The first metallic titanium pure enough to be malleable when cold was produced by Hunter1 in the early part of the twentieth century. Kroll,~ van Arkel,~ and Fast,4 subsequently confirmed the facts that pure titanium is a. ductile metal and that small amounts of impurities were responsible for previous reports of brittleness. When heated, titanium reacts chemically with various gases, such as hydrogen, oxygen and nitrogen; if the volume of gas thus absorbed is too great, the metal becomes brittle and unworkable. The principal difficulty in making ductile titanium is prevention of such contamination, and the success of a given process may be judged by the completeness with which it solves this difficulty in a practical manner. Of the gases mentioned, hydrogen is the least objectionable, since its absorption by the metal is completely reversible and, although dimensional changes occur and absorption of hydrogen embrittles the metal, the gas may be removed readily by heating in a high vacuum for a short time. On the other hand, the absorption of oxygen or nitrogen results in the formation of permanent solid solutions of the oxide and nitride, which cannot be decomposed by the strongest reducing agentsz with sufticient completeness to restore the inherent ductility of the metal. Because of

Jan 1, 1946

By Wilbur C. Helt

The United States is self-sufficient in bituminous coal and lignite resources to meet the high range of energy demands forecast for the remainder of this century and beyond. The known or proved recoverable reserves of energy from coal in the United States are estimated to be 88% of all fuel reserves, whereas the energy reserves for oil are estimated to be 276, gas 376, shale oil 5% and uranium 2% (as now used). The demand for all forms of energy used in the United States is increasing at a rate of 3% to 4% per year. Presently, coal is competitive on a supply and cost basis with other fuels in conversion to electrical energy and as a source of energy for converting raw minerals to metals and nonmetals, but it is not competitive in transportation and other uses that demand the high flexibility that oil and gas enjoy because of their form. Coal conversion to fluid forms is essential to make it interchangeable with gas and oil to meet the markets they now occupy. Essentially, the chemical constituents that make up coal are the same hydrocarbons that make up oil and gas; it is a matter of reconstituting the proportions of hydrocarbons to make coal interchangeable with the other fuels. The production of coal has fluctuated widely between the peak production of 631 million tons in 1947 to a low of 403 million tons in 1961. Throughout this period, the total value of the production, f.o.b. mines, has averaged more than $2 billion annually. Beginning with 1962, there has been a steady upward trend in coal production with only minor fluctuations that were mainly caused by labor disputes. Output for the latest typical year, 1970, was 588 million tons. Production in 1971 was affected by a major strike and dropped to 548 million tons. Exports of coal from United States to foreign countries have increased steadily and developed into a substantial annual market for over 71 million tons per year. About 56 million tons of this is suitable for metallurgical purposes, and the remaining 15 million tons is exported for electric power generation. The largest single-industry demand for coal is in the electric generating industry, Fig.1. Roughly, the production of electricity has doubled every

Jan 1, 1973

By T. S. Washburn

Deoxidation is one of the most complex metallurgical operations in the basic open-hearth process. The necessity for deoxidation arises from the fact that the refining operations that precede it require the oxidation of the steel bath. when the refining is completed and the desired composition of the bath has been obtained with respect to the elements subject to control by 'oxidation. there is usually an excess of oxygen present in the bath from the standpoint of the amount desired in the finished steel. The objectives of deoxidation are to control the amount and type of oxides and, although not directly ilnp1it.d by the term or always considered as a Part of the process, to control the amounts of gases such as hydrogen or nitrogen that will be present in the finished steel. There are other aspects to be consideretl in connection with deoxidizing procedures. In addition to the primary objectives of oxide and gas control. the composition of the steel is affected by the elements introduced during the deoxidizing process. Factors in furnace operations are likewise involved, such as slag composition, temperature control. arid heat time. .ill of these should be considered in establishing the most satisfactory deoxidizing procedure for each grade of steel. The purpose of this paper is to outline the objectives of deoxidation as related to steel characteristics, and to summarize the factors in furnace practice and the economic aspects to be considered in connection with deoxidation procedures. Objectives of Deoxidation The primary objectives of deoxidation are the formation and elimination of oxides. The amount of oxygen present in the bath prior to deoxidation is an important factor, since it is the basis of any deoxidation procedure. The oxygen content of the bath is primarily a function of the carbon content, although it is affected also by the temperature, the oxidation of the slag, and transient conditions within the furnace. The relation of oxygen to carbon in the bath is shown in Table I. Table I shows that under actual operating conditions, the amount of oxygen present in the bath is higher than the theoretical amount. This relation would be expected, since the bath is in a state of metastablc equilibrium during the period that the carbon is being eliminated. The most important feature demonstrated by this table, however, is the rapid increase

Jan 1, 1945

By Charles S. Barrett, Robert F. Mehl, Shueling Woo

WHEN one solid phase is generated from another, fixed and rational orientation relationships are observed to subsist between the parent and the new crystal. The principle has been proposed' that the relationships obtaining between the same two phases are identical whatever the type of phase change involved, or whichever of the phases may act as parent. Many types of phase changes have been studied: allotropic transformations in pure metals, precipitation from solid solutions, eutectoid decompositions, peritectic reactions, the formation of oxide layers, and others.2 Phase layers generated by diffusion of one metal into another constitute an additional type of reaction. This report provides new data on the orientation relationships occurring between , phase layers formed by diffusion, in the Cu-Zn system, § and furnishes further evidence in support of the principle. MATERIALS AND METHODS The Cu-Zn system is especially suitable for these studies since the high vapor pressure of Zn provides an opportunity readily to create one phase poorer in Zn upon a parent phase richer in Zn by removing Zn by vaporization, or to reverse this process by adding Zn from Zn vapor; e.g., the beta phase can be found as a layer upon gamma by dezincing, or gamma can be found on beta by addition of Zn from Zn vapor. Since orientation relationships are to be sought, requiring crystals large enough for orientation determinations, it is convenient to prepare single crystals or large grains of the parent phase. The samples were prepared from oxygen-free high-conductivity copper and Horse Head zinc by melting under a borax flux in a graphite crucible. Large crystals of beta brass were grown by the strain-anneal method, in plates sectioned from the cast ingots, by the following procedure. Rockwell-hardness indents were made at I cm. intervals-and with various loads, then the plates were annealed for .4 days at 700°C. in Nichrome boxes packed with beta-brass chips and graphite. Surface layers were removed by grinding and etching to a depth of about 1.0 mm., and individual grains were cut out. Crystals of alpha and gamma brass were prepared by freezing, by lowering a graphite crucible at speeds less than one inch per hour through a furnace held at a constant temperature above the melting point. Single crystals were cut out with a jeweler's saw, ground, polished and etched. Care was taken to remove cold worked layers from the finished crystals

Jan 1, 1944

By William S. Hannan, H. Rush Spedden

FLOTATION may be defined as a process whereby mineral particles are concentrated by selective adhesion to air-liquid interfaces. The process involves attachment of desired mineral particles to air bubbles, and removal of the mineralized air bubbles from the surface of the pulp as a mineral concentrate. PROBLEM Although great strides have been made in understanding the principles of flotation, one part of the process which has not been adequately explained is the mechanism by which selected mineral particles become attached to air bubbles. A glance at the froth of an operating flotation cell demonstrates adequately that use of proper reagents and conditions will result in such attachments; but how such attachment takes place is not definitely known. A better knowledge of this factor might lead to improved flotation practice either through altered machine design or the application of scientific innovations. Direct observation of the behavior of mineral particles and bubbles in an operating cell does not appear promising because of the complexity of the system. For this reason, conclusions concerning the problem must be deduced from theoretical considerations or from observation of simplified systems designed to reproduce conditions thought to exist in an operating cell. PRESENT THEORIES Two mechanisms have been recognized as fundamental in particle-bubble attachment: gas precipitation and direct encounter. It is a simple matter to demonstrate in the laboratory that attachment can be brought about by either mechanism. As to the relative importance of the two in a particular flotation system, however, there is a divergence of views. Taggart1 states, Under exceptional circumstances sufficient force and time to effect attachment may conjoin in an ore pulp undergoing agitation, and a preformed bubble adhere to a collector-coated mineral particle, but the occurrence is rare. . . . Pulp-body froth flotation effects selection in the body of a conditioned pulp by causing gas bubbles to precipitate from solution in the liquid phase preferentially at the surfaces of collector-coated particles, and to cling to these particles. Gaudin2 states that, within the pulp body of an agitation machine, attachment of mineral particles to air bubbles occurs as a consequence of contact between the two. This theory has been supported by theoretical reasoning and much circumstantial evidence. Perhaps the most interesting bit of evidence in favor of this theory is the difficulty in the flotation of fines. If attach-

Jan 1, 1947