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By G. Stokreef, B. R. Davis, M. Kadiyski, T. LeBel, Alvear Montenegro, R. Parra, V. Montenegro

A drop tower and methodology were developed to study the impact of mineralogy on the flash combustion behaviour of copper concentrates. Reaction shaft conditions of a flash furnace were simulated using a drop tower reactor and different molar ratios of oxygen gas to sulphur in the feed. Five feeds were tested in the drop tower including pure minerals chalcopyrite and pyrite as well as two mineralogically distinct copper concentrates and a blend of the two. The behaviour of each of these five feeds were evaluated through analysis of the solid combustion products for elemental sulphur, mineralogy and particle size. Desulphurization curves for each of the feeds were produced. It is thought that the desulphurization behaviour of pure minerals can be used to estimate the behaviour of a concentrate and that a blending recipe could be developed, which can optimize the chemical and mineralogical inputs to the flash furnace and guide operations on the optimum furnace conditions. Overall, the drop tower has proven to be a useful tool for studying flash combustion processes. Experimental results suggest that mineralogy has a significant impact on the conditions required for the production of matte with consistent grade. This finding is especially significant for custom smelters, which may see several different blends in a day. INTRODUCTION Flash furnace smelting is a continuous feed, batch tap, pyrometallurgical process that is used to produce copper matte from copper sulphide concentrates. Dried concentrate(s), silica flux, and secondary materials are blended to a target chemical composition, typically given by the Cu/S ratio, before processing. This fine, dried feed is dispersed throughout the heated furnace reaction shaft with an O2-enriched reaction gas. The particles heat up in the shaft of the furnace, ignite and undergo reactions that pre-oxidize the iron sulphide and some of the impurities in the feed. Oxidation reactions in the shaft of the furnace desulphurize the feed and produce an SO2-containing off gas. The reacted particles fall into the furnace settler and separate into a Cu-rich matte and an iron-silicate slag, while the SO2-containing off gas is carried out of the furnace for heat and dust recovery, as well as H2SO4 production. Some concerns during operation of the furnace are dusting, over or under oxidation of the feed, and a stable flame.

Jan 1, 2019

New South Wales (NSW) and Queensland dominate Australian black coal production and exports. NSW produced 86 Mt (95 million st) of saleable coal in 1994, a doubling of output since 1980. Asian demand for thermal and coking coal has driven this growth. This high Asian demand is expected to continue and NSW will seek to secure its share. History The history of the New South Wales (NSW) coal industry can be traced to 1797 when coal was first taken from Newcastle to Sydney (Ellis, 1969). At that time, NSW was a British colony, independent from the other colonies, such as Victoria and Queensland. Australia, as a federation of colonies, did not exist until 1901. The Newcastle coal industry grew through the 1800s in line with the growth of the colonies. Several events spurred demand for Newcastle coal. These included: ? The NSW and Victorian gold rushes of the 1850s and associated population growth. ? The development of steamship traffic at the expense of sail. ? The development of railways and town gas supplies. By 1900, Australia was producing 6.4 Mt (7 million st) of coal, most of it from NSW. By then, NSW had established strong export markets in Indonesia, China, Japan and New Zealand. The history of energy consumption is marked by continual competition, changing intensity of use and substitution. From 1900 to 1940, the Queensland, Victorian and Indonesian coal industries developed at the expense of NSW exports. Similarly, New Zealand developed its hydroelectric industry and thus declined as the largest customer for NSW coal. Oil replaced steam in the shipping and railway markets and electricity replaced gas for lighting. Industrial efficiencies also affected coal. Between 1928 and 1938, coal consumed in generating power fell from by 17% on a kilowatt hour basis and, during the same period, the amount of gas produced per ton of coal rose by 18% (Shaw and Bruno). Faced with these pressures, production and exports stagnated. By 1941, Australian black coal production was 14.2 Mt (15.6 million st). NSW's production was 11.7 Mt (12 million st), up only 19% from 1912. Exports had virtually ceased (Fig. 1). In such circumstances, the industry had lost focus. Unions resisted the need for mechanization, for security of employment reasons, and owners were loath to invest. This reluctance to mechanize and the associated in-

Jan 1, 1997

By B. H. Lehnhard, C. J. Cecil

The paper describes the use of the Electric Pilot in the Permian Basin for making permeability surveys of wells and for the selective acidization of wells. A general summary of the information obtained from the many permeability surveys run in this area is given, and the possible application of this information to reservoir control problems is discussed. The application of the Electric Pilot on specific wells, involving well completion, acidizing and workover operations is also included. Introduction The Electric pilot is a comparatively new tool in oil-producing areas. From the beginning, the possibilities of this new service caught the imagination of many of the oil operators and acidizing engineers. Through the continued and ever increasing use of the pilot during the past year, and the close cooperation of the oil operators who have used this service, the efficiency and utility of the Electric Pilot service has been increased to a point where it is now a well established and recognized service. There are two major uses for the Electric Pilot: (I) permeability survey; (2) selective acid treatments. Permeability surveys are made to determine the thickness of the various permeable sections at the borehole, the vertical position of these zones at the bore hole, and the relative capacities of the various zones. Nomenclature Data obtained from the permeability survey are used to calculate three different indexes that pertain to the volume of fluid injected into the various permeable zones. A nomenclature for these various indexes has been set up, which correspond with the various productivity indexes, except that they are a measure of injected fluid rather than produced fluid. The nomenclature and definition of the indexes used in connection with a permeability survey by the Electric Pilot are as follows: 1. Capacity.—The volume of water injected into an individual permeable zone, in gallons Per minute. 2. Capacity Index.—The volume of water injected into an individual permeable Zone, in gallons Per minute Per pound Per Square inch differential Pressure. 3. Specific Capacity Index.—The volume of water injected into an individual permable zone in gallons Per minute Per pound per square inch differential per foot of thickness of the zone at the borehole. Capacity is the most generally used index, and for planning initial acidizing procedures and most workover jobs it is sufficient. For comparing permeability surveys on the same well before and after

Jan 1, 1945

By E. G. Gaylord

A BRIEF review of the oil conditions in California for a few years prior to 1923 is desirable for a clear comprehension of the development during that year and the results of the development. California's oil production during the five years preceding 1922 had been running from 100,000,000 to 115,000,000 bbl. annually. Crude oil stocks in storage had been declining steadily from 1915 to 1919, when there was a slight increase. They continued to decline through practically all of 1920, when they were drawn on to the extent of 11,350,000 bbl., leaving 20,930,000 bbl. on hand. In 1921, with production approximately 10,000,000 bbl. greater than the previous year, crude-oil stocks increased until, at the end of the year, there were 33,289,000 bbl. on hand. It would seem, therefore, that at the end of 1921 the so-called Pacific Coast province could absorb between 100,000,000 and 105,000,000 bbl. of oil per year, any in excess of this amount going into storage, not being, able to compete in other markets with oil outside the state. During 1922, daily production increased from 316,000 bbl. at the beginning of the year, to 500,000, at the end. This increase was the result entirely of production from the new fields, in the Los Angeles basin. In fact, considerable oil from the older fields of the state was shut-in beginning with March, 1922. As of 1922, the past development of the oil industry of California had been, in a general way, quite regular. As the need grew for more oil, pioneer drilling was increased, resulting in the discovery of new fields here and there. The good prices for crude oil that prevailed during the later part of the War and into 1921 had stimulated an extensive wildcatting campaign by California's larger oil corporations, as well as by smaller independent oil companies and by individuals. Many wildcat wells in California have required, two or three years for their completion, consequently the intensive wildcatting, which might be said to have started in California in 1917 and continued into 1922, found its greatest results with, the discovery of three very productive fields which, for all practical purposes, might as well have come in simultaneously.

Jan 3, 1924

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 Jay A. Carpenter

This paper deals with only one step in the treatment of ore at the West End mill; not because the other steps are repetitions of practice in other mills, but because in this particular step there is in use the Trent agitator: This device, although it has apparently failed in many mills, is here giving excellent service and has proved to be well adapted for making a thorough replacement of pregnant solution with a minimum amount of barren solution. The strong and weak points of this agitator, its present simple construction, and its use as a thickener for agitator or battery pulp are features of interest; but perhaps the point of greatest interest to the metallurgist in this day of continuous decantation is its use in a series of tanks for slime treatment by the replacement method. The agitating department of the West End mill consists of six redwood tanks, 24 ft. in diameter, 18 ft. high, each equipped with a Trent agitator, a centrifugal pump, and a motor. The pulp is transferred by a pump from the top of a flat-bottomed tank to a set of arms and nozzles in the bottom of the tank, at just sufficient pressure to cause the arms to revolve. The streams from the many nozzles keep the bottom of the tank clean, and these streams, coupled with the effect of the revolving mechanism and the ascending current, keep the pulp in constant motion and of constant gravity. These agitating tanks hold 90 tons of dry slime and 202 tons of solution with a 1.24 pulp, our ore having a specific gravity of 2.7. This capacity is about 10 per cent. in excess of the standard 15 by 45 ft. Pachuca tank. The tanks are connected in one series for continuous agitation, the pulp for each agitator being drawn by its pump through a branch suction from near the top of the preceding tank and delivered to the bottom of the tank by the agitator arms along with the regular pulp of that agitator. This method works automatically, since the flow through the branch suction varies directly with the difference in head of the two tanks. The chance for new pulp to pass out quickly is, therefore, much less than in many other systems of continuous agitation, since the new

Jan 1, 1916

The only good news in the exploration sector in 1982-a year plagued by low metal prices and weak demand-was precious metals. Gold in particular remained in the forefront, as it has for at least the past three years. The reason for this is partially due to gold's seeming resilience to conventional supply side factors-such as new production-that normally influence many other metals. Also, with projected production costs of about $6.40-$9.65/g ($200¬$300/oz), modest deposits with average grades can offer an early return on capital investment and good profit potential. Keeping escalating capital costs for new mining ventures within reason has shifted gold exploration efforts in recent years. Many mining companies are seeking relatively low grade, modest tonnage, near-surface gold mineralization. This, of course, leads to lower development costs using open-pit mining methods. Recent refinements in the carbon-in-pulp recovery process also has enhanced the economics of such deposits. Slumping economic conditions certainly played a key role in shaping exploration activity last year. Nearly every major mineral-producing state recorded exploration slowdowns. In Alaska, for example, development expenditures approached the level of exploration spending for the first time in the state's history. This not only reflects major companies' decisions to move toward production but also the economic slowdown. The worldwide recession stopped Nevada's exploration and mining boom "dead in its tracks," said John Schilling, state geologist. The year was one of layoffs and closings for the state's mines and exploration offices, he reported. Similar trends were noted in most other states, especially in the West and Southwest. In the Pacific Northwest, however, exploration appeared to continue at a relatively good pace considering the metals market. In the mining geophysical community, recent advances in telecommunications and microprocessor technology are continuing to provide a positive impact. Many geophysicists have begun using satellite digital communication links to access computer systems from remote sites where using a microcomputer would be difficult. There were also major contributions made in exploration geochemistry last year. Highlights include progress in formulating mineral deposit models, geochemical exploration in glaciated and arid environments, and publication of many informative books. The following state-by-state summary and articles on geophysics and geochemistry provides a detailed view of exploration events throughout the US in 1982.

Jan 5, 1983

By R. E. Wade

The Butte, Anaconda & Pacific electrification is of peculiar interest, in an incidental way, to the entire mining fraternity, and especially the engineering branch, not only in this great Northwest country but throughout the entire Western mining country, which is rich in minerals and water power. It is probably fair to say that the prime object of mining and smelting engineering is to reduce the cost of production, and in the case in hand the relative location of mines and smelter brings the cost of transportation of ore to the front. While some might assign this item to the railway people, it is inseparably a part and parcel of the general scheme of the production of metal from the ore. In considering the electrification of the B., A. & P. railway the mining and smelting engineer, above all, wants to know what saving will be effected by the change in motive power. Unfortunately the new power has been in use during a very limited period and on the Smelter Hill section of the road only, and no reliable data, from actual service conditions, can be obtained until the entire electrified section has been in service for a reasonable length of time. Any remarks on this subject at the present time, therefore, must of necessity be general in nature and more or less descriptive. The railway, electrical and mining worlds and the country in general are indebted to the B., A. & P. railway for the pioneer work it is now doing, as it undoubtedly marks the beginning of the electrification, within the comparatively near future, of all transcontinental roads between the Missouri river and the Pacific coast. Together with this goes the development of an untold wealth in water power and all natural resources within the same territory. For the first time in the history of electric railway work, in this country, direct current at a potential of 2,400 volts is being used. With this potential there is a great saving in transmission of energy to the locomotives and there are only two substations, one at either end and 26 miles apart, for supplying the power for the movement of trains of heavy tonnage over the main line and for switching movements at terminal and intermediate yards, and comparatively little feeder copper is required.

Jan 1, 1914

By Perry Olcott

The Texas Gulf Coast had a rather disappointing year in the type of oil fields found. Although 17 fields were found in the area during the year, as against 21 fields in 1938, no field of major proportion was discovered. Of these 17 fields, 11 were oil fields, 4 were gas and distillate fields, and 2 were gas fields. The wildcat activity for the year resulted in about 400 dry holes, although probably 10 per cent of these were edge wells close to proved areas. During the year, 1455 oil and gas wells were completed as compared to 1637 wells in 1938, a decrease of 11 per cent. Production for the Texas Gulf Coast area for the year was 100,253,937 bbl. as against 92,530,467 bbl. produced in 1938, an increase of 8 per cent. The daily average production was 274,668 bbl. for the 365 days in the year, although only 252 producing days were allowed by the Railroad Commission; that is, 69 per cent of the time as compared to 71 days shut in for 80 per cent of the time producing in 1938. The total number of oil and distillate wells producing at the end of 1939 was 9495 as against 8451 at the end of 1938—an increase of 1044 wells, or 12 per cent. Of these wells, 6547 were flowing and 2948 pumping, or 69 per cent flowing. At the end of the previous year, 66 per cent of the wells were flowing. New Fields Angleton, Brazoria County.—The Angleton field was discovered by the completion of Glen McCarthy's No. 1 Carr in October for an initial production of 180 bbl. a day of 50" gravity oil through 11/64-in. choke with 3400 Ib. on tubing. The field is 1½ miles east of the town of Anchor. The discovery undoubtedly can be credited to the reflection seismograph, since several companies worked the area from 1933 onward with this type of exploration. The principal block was taken by the Humble company in 1934. Two deep holes by Humble revealed the presence of structure, although both were dry. The Humble and Sun companies later contributed money and acreage toward the drilling of the discovery well. The production is from a sand in the Frio, about 1700 ft.

Jan 1, 1940

By Joël P. T. Kapusta, Liam J. Watt

The last extended copper smelting and converting survey dates back to the 2003 International Copper Conference held in Santiago, Chile. The following year, the Minerals, Metals, and Materials Society of AIME (TMS) started a new series in its Journal of Metals (JOM) called JOM World Nonferrous Smelters Survey devoting its first Part to Copper. The copper smelting landscape has significantly changed in the past 15 years, both in geographical terms with the shift of copper smelting production from the Americas to China and in technological terms with the growing adoption rate of Top-Submerged Lancing (TSL) technologies and the development and implementation of Bottom-Blowing technologies. A copper smelting survey update, even if not as in-depth as the 2003 Copper Smelting Survey, is therefore in order. The authors will review the latest trends in copper smelting technologies and production worldwide in comparison to the landscape of the early 2000s. INTRODUCTION This 2019 copper smelting survey is different from previous surveys as our data does not originate exclusively from responses to a questionnaire sent to all the copper smelters. Our data comes from several sources. We are therefore very thankful to the International Copper Study Group (ICSG) and Wood Mackenzie for sharing some of their information and to ENFI, Outotec, and Glencore Technologies for helping us cross-check our numbers for the Chinese smelters, flash smelting, Ausmelt, and Isasmelt technologies. Our survey presents data reporting from a total of 96 operating copper smelters from around the globe, which is significantly higher than the 50 surveyed in 2003. Although secondary smelting numbers have steadily increased over time, this paper focuses on primary smelting operations with copper concentrate as feed material. The list in this survey is still far from complete, with missing information from several known smelting operations. The total primary copper production tonnage of the smelters we surveyed amounts to 18.3 million metric tonnes from 29 countries representing 92% and 94% of total world primary production for 2018 estimated by ICSG and Wood Mackenzie, respectively. This representation has increased from 2003 when the total was 9.71 million metric tonnes from 23 countries accounting for 73% of world production. The trends presented and analyzed within this paper have stronger significance because of the increase in production accounted for. The Chinese and Russian smelter information collected is more detailed than years past. Our complete dataset is summarized in Table 1 at the end of our paper.

Jan 1, 2019

By Adrian C. Dorenfeld

Laboratory data form the basis for the design of flotation circuits. These data, obtained from testing samples of the ore, should show the optimum con- ditions for concentrating the ore and the effects of change in process vari- ables. Among the more important variables commonly met in flotation practice are: Liberation Size-This is the particle size at which substantially all of the valuable minerals are detached from the gangue minerals. Reagent Additions- Experimental data will show the reagents used and their quantity, quality, and point of addition. Pulp Density-This is an important variable in the design of the flotation circuit because it is one of the factors determining the size and number of flotation cells. Flotation Time-The time necessary to make the separation into concentrate and tailing depends on such factors as particle size and reagents used and must be known for determination of the size and number of flotation cells in the plant. Temperature of Pulp-Temperature affects flotation reactions. Water at approximately room temperature is satisfactory for most flotation separations, but some minerals such as fluorspar are best floated in hot water. Type of Circuit-Many types of circuits can be designed, as discussed in detail later. The laboratory tests should provide data for design of the plant circuit best suited to the ore. Water-Knowledge of the quality of the future plant's raw water is important because water quality may drastically affect flotation results. If possible, flotation tests should be made using samples of the water to be used in the plant. Flotation results may vary with seasonal temperatures and with circulation of reclaimed water. Experimentation can show whether it will be necessary to provide for heating, cooling, treating, or reclaiming the water. Uniformity of Ore-The extent of variation of the ore in hardness, grind- ability, mineral content, and floatability should be investigated so that the designer can ascertain methods to overcome problems caused by ore variations. Settling and Filtration Data-To design the plant flotation circuits, settling and filtration rates and ultimate percentage solids of the various products must be determined. Corrosion and Erosion-Corrosion and erosion tests should be made on the flotation pulps, particularly if the pulps are acid or at an elevated temperature, so that suitable materials of construction can then be chosen.

Jan 1, 1962

By C. Chiou, D. P. Seraphim

The effect of clustering on the superconducting properties of Al-Zn alloys has been studied by the ballistic induction techniques. The superconducting critical temperature, T,, changes when zinc-rich clusters are formed. The change in T, depends on the concentration and may be positive or negative, but always correlates with an effective decrease in the solute concentration of the alloy. Reversion after clustering effectively returns a 5 at. pct Zn alloy to the quenched state. These methods might be use&lly extended to the Al-Mg system, where X-ray data are difficult to obtain. In very dilute Al-Zn alloys, as in other tin,' indium, aluminum,2 or tantalums base solid solutions, there is a decrease in the superconducting critical temperature, Tc, roughly proportional to the temperature independent resistivity, i.e., -0.2°K per pS2cm. With increasing solute concentration, the T, generally reaches a minimum and then increases4 to a value well above that for the pure solvent. The change of T, with solute concentration follows an empirical formulation involving two constants which correlate with the scattering cross section of the impurities. As will be shown below, the Al-Zn alloys more concentrated than 1or2at. pct do not follow the empiricism, probably because they are unstable even when rapidly quenched.5 However, it seems possible to study at least the later stages of solute clustering by precise measurements of the 1', following various thermal treatments. A few experiments on quenched alloys, aged alloys, and tests on reversion are reported here. The heat treatments selected for obtaining the quenched and aged states were mainly deduced from the work of Dash and Fine.6 For the quenched state, specimens were homogenized at 480°C, quenched to -160°C, and immediately transferred and mounted in liquid nitrogen. Measurements on the superconducting properties and residual resistivities were then made at helium temperatures, after which the specimens were aged at room temperature for 3 to 5 hr, i.e., much longer than the time required for clustering to be essentially completed. The superconducting properties and residual resistivities were once again examined. To reach the reverted state of the A1-5at. pct Zn alloy, the aged specimen was heated for 5 min at 200°C and then tested as above.

Jan 1, 1963

By A. P. Boller

In the victories of peace as well as of war, the science of engineering has played a prominent, if, indeed, not the leading part. While it might be interesting, and food for profitable thought, to trace the development of engineering from early times in its bearings upon the social betterment of mankind, it will be sufficient on the present occasion to suggest a few thoughts that it is hoped will aid the unprofessional listener to an appreciative consideration of the subject-matter laid down for to-day's discussion, and possibly lead the professional brother to a higher conception of the profession to which he belongs. Since the advent of the railway era, it is difficult to grasp the sequence of historic events that have led to the wondrous derelopment of mechanical science, making possible the civilization that is our daily boast, and opening up a vista of future intellectual and moral advancement among the nations of the earth, 'before which the imagination becomes hopelessly lost. Even now, looking back over a period of only half a century, we often fail to realize the vast change in the relations of individuals and nations to each other., brought about by the results of those mechanical discoveries which, having made the whole world kin, exercise a resistless levelling influence that bears fruit politically in the spread of republican ideas, and morally in the elevation of the individual through the facilities given to the dissemination of Christian ideas and general intelligence. In this view, it seems almost like a work of supererogation for a body of representative men of one department of that science to which the whole world owe. so much, to meet here at the centre of our national life to plead not only for a practical recognition of the national importance of the work to which their lives are devoted, but also for national aid, on a scale beyond that of private effort, to the end that mechanical science may be carried to a higher plane than ever yet attained, each step on the way being of material benefit to every man, woman, and child in the community. Possibly this is strong language, but none too strong when we consider that the work for which we plead is one affecting not only vast scientific and commercial interests, but also human life, to a degree little ap

Jan 1, 1882

By Perry Olcott

The Texas Gulf Coast had a rather disappointing year in the type of oil fields found. Although 17 fields were found in the area during the year, as against 21 fields in 1938, no field of major proportion was discovered. Of these 17 fields, 11 were oil fields, 4 were gas and distillate fields, and 2 were gas fields. The wildcat activity for the year resulted in about 400 dry holes, although probably 10 per cent of these were edge wells close to proved areas. During the year, 1455 oil and gas wells were completed as compared to 1637 wells in 1938, a decrease of 11 per cent. Production for the Texas Gulf Coast area for the year was 100,253,937 bbl. as against 92,530,467 bbl. produced in 1938, an increase of 8 per cent. The daily average production was 274,668 bbl. for the 365 days in the year, although only 252 producing days were allowed by the Railroad Commission; that is, 69 per cent of the time as compared to 71 days shut in for 80 per cent of the time producing in 1938. The total number of oil and distillate wells producing at the end of 1939 was 9495 as against 8451 at the end of 1938—an increase of 1044 wells, or 12 per cent. Of these wells, 6547 were flowing and 2948 pumping, or 69 per cent flowing. At the end of the previous year, 66 per cent of the wells were flowing. New Fields Angleton, Brazoria County.—The Angleton field was discovered by the completion of Glen McCarthy's No. 1 Carr in October for an initial production of 180 bbl. a day of 50" gravity oil through 11/64-in. choke with 3400 Ib. on tubing. The field is 1½ miles east of the town of Anchor. The discovery undoubtedly can be credited to the reflection seismograph, since several companies worked the area from 1933 onward with this type of exploration. The principal block was taken by the Humble company in 1934. Two deep holes by Humble revealed the presence of structure, although both were dry. The Humble and Sun companies later contributed money and acreage toward the drilling of the discovery well. The production is from a sand in the Frio, about 1700 ft.

Jan 1, 1940

By J. E. Elliott, K. O. Miller

Solubility studies were carried out to establish the phase distributions for various Fe-Ni-Pb-C alloys at temperatures where the metallic components exist as liquid solutions. Temperature us composition diagrams for the Ni-Pb, Fe-Pb, Fe-Ni-Pb, and Ni-Pb-C systems are derived by employing various approximations in conjunction with the data. Results are summarized for 1550°C in a quaternary phase diagram of the Fe-Ni-Pb-C system. BECAUSE surprisingly little information has been published on the phase diagrams of the Ni-Pb, Fe-Pb, Fe-Pb-Ni, and Fe-Ni-Pb-C systems, a study of these systems was undertaken to ascertain the important phase relationships in the temperature range of 1300" to 1550°C. Measurements were also made on the carbon-saturated systems in the hope that they would assist in the interpretation of the systems without carbon. This paper reports the results obtained from the simple equilibration of the various liquid and solid phases. EXPERIMENTAL PROCEDURE The experimental technique involved holding appropriati quantities of the metals in an alumina crucible, or in a graphite crucible when saturation of the melt with carbon was desired, for sufficient time at the desired temperature to ensure equilibrium. Then a sample of each liquid phase presen was drawn into a small-bore silica tube. This sample was withdrawn quickly from the furnace, cooled, and sent to the chemical laboratory for analysis. The cell assembly used is shown in Fig. 1. Durin the work on the Fe-Pb-Ni system, it was placed in a furnace wound with 20 pct Rh-80 pct Pt wire. This furnace eventually failed and subsequent studies were carried out between 1350" and 1475°C in a tube furnace heated by silicon-carbide resistance elements. A protective atmosphere of argon with approximately 10 pct hydrogen was supplied to the cell assembly at a gage pressure of 1 in. of water. Hydrogen was passed over palladized alumina and then anhydrous calcium chloride for purification. Argon was purified of oxygen and water vapor by passing it over copper gauze at 550°C and then through a calcium chloride drying column. The gases were mixed and redried before they entered the equilibration cell. Temperature was measured by calibrated Pt/Pt-10 pct Rh thermocouples and a Rubicon Type B potentiometer. The thermocouples were standardized against the melting points of pure nickel

Jan 1, 1961

With the exception of the mentions of coal in Illinois in the period 1660-1680, already referred to, the first coal found in the United States was in the James River, Virginia, field. In 1699 a large tract of .land above the present city of Richmond was allotted for a settlement of French Huguenots by the colonial, government, near the present Manakin, about fourteen miles above Richmond. They soon found coal, tradition says it was uncovered by a hunter pulling out a small tree in a. steel) bank near a stream, and Colonel William Byrd, F.R.S., the most prominent man of his day in the colony, wrote to the Colonial Council of Virginia, May 10 and 11, 1701: "The 10th of May, last., I with Coll. Randolph, Capt. Epes, Capt. Webb, &c., went up to the new settlements of ye French Refugees at ye Manaken Town.... We went tip to ye Cole, w'ch is not above a mile and a half from their settlement on the great upper Creeke, w'ch, riseing very high in great Raines hath washed away the Banks that the Coal lyes bare, otherwise it's very deep in the Earth, the land being very high, and near the surface is plenty of Slate.", Some of the Frenchmen were evidently familiar with the use of coal, as on May 22, 1702, "David Menestrier a black smith and one of ye french Refugees Inhabiting at Luciana Petitioning his Excellency that he may have leave to use ye coal mines lately discovered there for his forge his Excellency by and with ye advice of ye Council loth hereby give Leave to ye said David Menestrier to take what coales he shall want. out of ye said Coal mine for ye use of his forge according to ye Prayer of ye said Petition."2 There was some uncertainty about the grant of these lands to the Huguenots which caused the request for leave to use this coal, as a Virginia patent in its usual form allowed the owner to mine all minerals excepting gold and silver, which were subject to royalties for the Crown. After the visit to the coal above mentioned, "Wm. Byrd, understanding the land had not been granted to the French, took out a patent for 344 acres, including the same, (the coal) which patent was dated October 20, 1704".3

Jan 1, 1942

By L. H. E. Weyher

The Bethlehem Mines Corp. is a captive mining subsidiary of Bethlehem Steel Corp. Its coal production is tied to the demands for and production of steel, a situation that has to balance between the following two extreme strategies: (1) either the mines are designed and operated for some optimum production level and the demand fluctuations within the steel corporation are met by supplementary corporate coal sales and purchases, or (2) the mines absorb all the demand fluctuations, regardless of the effects on mine costs. A rational definition of the best strategy between these extremes is, of course, needed but is very difficult to formulate in view of the complexity of the many factors that would have to be included in the analysis. Consequently, rather than setting profit targets for each given mining division and/or individual mine, the practice evolved to set production targets for producing specified tonnages of coking coal for shipments to the ovens located at the corporation's iron and steelmaking plants. This in turn leaves the mines with the dilemma of having to explain demand-related cost-per-ton fluctuations while essentially depriving them of the ability to control profit through tonnage optimization. In the early 1970's, the coal prices rose significantly, while other factors led to sagging productivity in underground coal mining. Thus, the role of Bethlehem's coal operations in the corporate profit picture gained in relative importance. This, in turn, sparked a closer attention to the coal mining cost structure and factors controlling productivity. At the same time, the drastic increase in the capital needed to open a new mine also increased the amount of planning required to minimize risks. All of this called for more well-defined, quantitative operating data. Bethlehem therefore launched, in the early 1970's, a number of innovative steps that, as the future may show, represented pioneering contributions to the growing sophistication of North American underground coal mine planning and management control practices. This case study describes the changes that led to the current implementation of a novel production reporting system at Bethlehem's coal mines. These changes took place in two distinctly different phases. The current system that resulted from the Phase II developments utilizes, of course, experience gained earlier and is expected to be amplified to incorporate more advanced concepts and technology as future experience dictates.

Jan 1, 1979

By Dean H. Herrick

The production of crushed stone in the United States has exceeded 1.0 Gtpy since 1987. Eighty percent of the crushed stone produced is used in the aggregate industry, accounting for over half of the quantity of natural aggregate consumed in the United States. Approximately 718 of the crushed stone produced in 1989 was limestone and dolomite followed by granite, traprock, sandstone and quartzite, miscellaneous stone, marble, shell, calcareous marl, volcanic cinder and scoria, and slate in order of descending volume (Table 1). Of the remaining 20% crushed stone produced in the United States and not used as aggregate, 12% is used in the manufacture of cement which is an important construction material. Only 8% of crushed stone is used in specialty products not associated with the construction industry. Therefore, this chapter will concentrate on crushed stone as used in aggregates, with occasional reference to other uses or to chapters which discuss specific nonconstruction uses of crushed stone. Construction aggregates are hard, essentially inert materials suitable for being formed into a stable mass by the addition of cementing or binding materials that produce a concrete by compaction, or by natural weight to produce a road or foundation fill. Aggregates are usually from 80 to 100% of the material volume of the construction masses in which they are used. Conditions necessary for a rock deposit to be developed for construction crushed stone include: Quality-should pass rigid specifications for strength and durability; Quantity-adequate volume of rock is needed to have a production life of at least 10 years, preferably 20 or more years; Market-must have adequate market to support a new crushed stone operation; Transportation-transportation cost must be competitive for the intended market; Environmental-the impacts of mining, processing and transportation of crushed stone on the environment at or surrounding the mine site must be within acceptable limits; Permitability-mining, processing and transportation of crushed stone must usually be permitted by governing agency. The following discussion will touch upon all facets of crushed stone operations from the mineral deposit and its geology to technology, uses, economic factors and end with governmental regulations of mining crushed stone. The sections are not designed to answer all questions, but rather to be an introduction to the crushed stone industry. Where more information is required, The Aggregate Handbook by Barksdale (1991) is recommended as the best general source.

Jan 1, 1994

By A. R. Elsea, C. C. McBride

HIGH-TEMPERATURE alloys, that is, alloys that are strong at high temperatures, have become increasingly important with the development of modern aircraft engines. Many alloys of this type are available. However, metallurgists do not have a clear understanding of the phases or structures which are responsible for these high-temperature properties. If these basic factors were understood, it might be possible to make better or cheaper alloys for service at high temperatures. For this reason, an investigation of the fundamental factors promoting high-temperature strength in alloys was started at Battelle Memorial Institute. This was to have included a study of the relationship between the structure and properties of cobalt-chromium base alloys of the vitallium type. It soon became clear that the structure of vitallium is quite complex and that the equilibrium diagrams which should explain these structures were unreliable. As a result, the cobalt-chromium binary diagram was determined as the first phase of this investigation1. This diagram is shown in fig. 1. During the study of the cobalt-chromium binary system, it was learned that these alloys may pick up considerable nitrogen when melted and heat treated in air. The extent to which nitrogen affects the various reactions in cobalt-chromium base alloys was not known, but there were indications that this impurity might be responsible for some of the erratic test results obtained for vitallium. Consequently, nitrogen was the first ternary addition studied. Thereafter the work was extended to ternary additions of iron and of nickel. This paper describes the investigation of the effects of nitrogen, iron, and nickel upon the reactions in cobalt-chromium alloys with 80:20 and 68:32 cobalt-chromium ratios. Experimental Work Alloy Preparation: A series of cobalt-chromium base alloys containing various amounts of the third element being studied were made for both the 80:20 and the 68:32 cobalt-chromium ratios. Electrolytic chromium, cobalt, and iron, and reagent-grade nickel powder were used as melting stock. Table I contains the chemical analyses of these materials. The charges were melted in alun-dum thimble crucibles which absorbed chromium oxide and effectively deoxidized the melts. These crucibles were supported by close-fitting graphite sleeves so that if they cracked during melting the metal would not be lost. Carbon increases, during

Jan 1, 1951

By W. J. Fene, H. B. Humphrey, J. J. Forbes

"INTRODUCTION Loss of life from coal-mine explosions in the United States in 1949 was the lowest in any year since before 1870. Although fatality reports from coal nines before 1910 were incomplete,' the explosion fatalities from single disasters or individual States exceeded the 1949 total in each year as far back as 1870, when the records become fragmentary. Since 1890, the only other year in which fewer than 35 were killed was 1946, with a total of 32. Figure 1 shows the total yearly fatalities from explosions in all coal mines and those in anthracite mines alone since 1870. The fatalities in bituminous coal mines were not completely reported before 1910, but enough reports were issued by major coal-producing States to compile reasonably representative figures back to 1885. Any corrections would be additions to these totals.The reason for the moderate total of 46 explosion fatalities in 1948 and the low total of 8 killed in 1949 is thought to be the serious and careful attention devoted to elimination of coal-mine explosion hazards after the disastrous explosions in 1947. The standards now being observed generally with respect to ventilation, rock-dusting, and inspections for gas are better than those found earlier in even the mines having the best reputations for safety. Exceptions are still numerous, but they are fewer, month by month, because of the pressure of Federal and State inspections and a changing conception of the hazards that should not be permitted underground. The prevailing precautions have not eliminated all ignitions of gas or dust, but they have limited propagation to small explosions and have prevented serious loss of life.The number of ignitions (14) reported for the year was less than the average (24) for the 5 years 1944-48 and only half the average for the fiscal years 1929-44. Another favorable factor is that Bureau of Mines representatives were probably in closer contact with both small and large mines in nearly all coal-mining districts. Inspectors now assigned to individual districts are better able to keep informed on the happenings and the progress of safety in their districts. In 1948, one-fourth of the explosions were in mines that employed fewer than 10 men; this condition was duplicated in 1949."

Jul 1, 1950