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By Richard Moldenke

One of the gravest problems of the iron foundry today is the accumulation of sulfur in commercial scrap and its effect on the castings made therewith. The ordinary jobbing castings today show a sulfur content of 0.18 per cent;, and occasionally as high as 0.22 per cent. The product of the foundry during the war is undoubtedly to blame for this rapid increase and conditions will become worse as the millions of tons of gray-iron castings of the war period return to the foundry in the form of commercial scrap. In the ordinary cupola remelting of pig and scrap, at least 0.02 per cent. sulfur is taken up; often double that amount. The high cost and difficulty of obtaining pig iron during the war period compelled the use of considerable scrap in the mixtures; frequently charges containing 90 per cent. of bought scrap were melted. Naturally the sulfur content of the castings increased. Until the advent of the basic-hearth electric furnace, the only method of holding the sulfur within reasonable limits was to use high percentages of pig in the foundry mixtures. Pig iron seldom contains over 0.05 per cent. sulfur, if well made. With pig iron forming 60 per cent. of the charge and the gates, runners, rejections, and bought scrap the other 40 per cent., the sulfur content of the castings can easily be held down to 0.10 per cent. Pig iron, however, costs more than scrap even when melting loss differences are considered, hence as small a percentage as possible will be used. The recent advance in knowledge of rational melting and the consequent reduction in losses directly due to oxidation of the metal and cold iron, has permitted the acceptance of castings with a much higher sulfur content than formerly. The steel industry also is seeking to determine how high sulfur may go with safety. In the iron foundry, however, there is the danger of a low cupola bed or an unduly retarded air-furnace heat, with the consequent raising of the freezing point of the metal and segregation effects resulting from high sulfur with insufficient manganese. The iron foundryman must, therefore, have a means of correcting his

Jan 1, 1922

By Richard Moldenke

One of the gravest problems of the iron foundry today is the accumulation of sulfur in commercial scrap and its effect on the castings made therewith. The ordinary jobbing castings today show a sulfur content of 0.18 per cent;, and occasionally as high as 0.22 per cent. The product of the foundry during the war is undoubtedly to blame for this rapid increase and conditions will become worse as the millions of tons of gray-iron castings of the war period return to the foundry in the form of commercial scrap. In the ordinary cupola remelting of pig and scrap, at least 0.02 per cent. sulfur is taken up; often double that amount. The high cost and difficulty of obtaining pig iron during the war period compelled the use of considerable scrap in the mixtures; frequently charges containing 90 per cent. of bought scrap were melted. Naturally the sulfur content of the castings increased. Until the advent of the basic-hearth electric furnace, the only method of holding the sulfur within reasonable limits was to use high percentages of pig in the foundry mixtures. Pig iron seldom contains over 0.05 per cent. sulfur, if well made. With pig iron forming 60 per cent. of the charge and the gates, runners, rejections, and bought scrap the other 40 per cent., the sulfur content of the castings can easily be held down to 0.10 per cent. Pig iron, however, costs more than scrap even when melting loss differences are considered, hence as small a percentage as possible will be used. The recent advance in knowledge of rational melting and the consequent reduction in losses directly due to oxidation of the metal and cold iron, has permitted the acceptance of castings with a much higher sulfur content than formerly. The steel industry also is seeking to determine how high sulfur may go with safety. In the iron foundry, however, there is the danger of a low cupola bed or an unduly retarded air-furnace heat, with the consequent raising of the freezing point of the metal and segregation effects resulting from high sulfur with insufficient manganese. The iron foundryman must, therefore, have a means of correcting his

Jan 1, 1922

By Norman Gerald

THE lack of a continuous operating balance in petroleum refining, which is analyzed in this paper, is by no means a feature solely of this division of the oil industry. Serious disequilibria of a capital as well as an operating nature exist both in the producing and marketing departments, while problems in the former and to some degree the latter are complicated by political involvements. Attention has previously been directed to the unstabilizing influence of present proration formulas in stimulating unnec-essary drilling.1 While equilibrium in petroleum refining operations has been fairly well maintained in the past decade, examination of departures may prove fruitful. Economic analysis is the application of time and motion study to the functioning of management, rather than labor. Properly applied it may reveal changes in policies that would increase the utility of the properties and facilities of the industry for stockholders, employees and the public, while contributing a stabilizing influence to the general economy. The study of economic equilibrium is essentially one of measurement and interpretation, requiring adequate data and the development of a tech-nique of analysis that employs statistical and mathematical methods as a supplement to the broad descriptive phase of economics. Economic equilibrium in petroleum refining is a dual concept. It embraces both the over-all balance between total storage and total demand for major products and the internal balance between the demands and inventories of the various products. The latter is the more complex of the two for it is concerned with proportionating the supplies of the several products stemming from the joint source to the demands for the individual products which are subject to wide variations. All the products are essentially nondurable goods, and they are used both by producers and consumers but in varying proportions. Motor fuel is very largely a consumer's good, while residual fuel oil is almost entirely a producer's good, the other products falling between these extremes. The peculiar-

Jan 1, 1939

By J. E. Nesset, J. A. Finch

A model of the fully-loaded condition of particle accumulation on the matrix of a high gradient magnetic separator is developed. The model accurately predicts the build-up profiles reported recently by Friedlaender et al. A powerful development from the model is that loading (volume of accumulated material per unit volume of matrix) is uniquely defined by a dimensionless group, called the loading number, NL. From direct measurements, NL proved superior to the dimensionless group proposed by Watson as a measure of loading. The fine size limit of hematite recovery is examined using NL.

Jan 1, 1980

By T. Reed Scollon

With some uncertainty as to the type, rate and scope of adoption of air pollution control regulations, and with limited information on the availability of low-sulfur fuels, it is possible at best to make only a rough assessment of the impact of such regulations on coal. It is apparent from the following discussion that regulations of the type already effective or being considered, if adopted and enforced on a widespread basis over a short-term period and if substitute fuels were available, both quantitatively and economically, could result in a loss of more than one-half of coal's markets. Depending on the areal sequence of adoption of such regulations, some areas would be able to obtain limited amounts of low-sulfur coals. Others would not. Because of the usually greater distances from the large industrial coal consuming areas to new sources of coal supply, and because of the higher mine prices for low-sulfur coals, the delivered prices of such coals as might be available would be much higher than those for high-sulfur coals. A large and sudden demand for low-sulfur coals would exert further upward pressure on prices.

Jan 1, 1970

By Ray W. Amstutz

The shaft was drilled on US government land m the Piceance Creek basin and was funded by the US Bureau of Mines (USBM). It was drilled to 723 m to provide access to rich deposits of oil shale, nahcolite, and dawsonite for geotechnical test work and environmental mining research. Rotary drilling and dual-string, reverse-air, jet-assist circulation methods were used. Drilling required eight months. Site preparation, running, and cementing the casing required another four months. A 2.44-m ID steel welded casing, 508 mm thick was installed and 2.7 kt of cement were slurried and pumped into the annulus.

Jan 1, 1982

By Clarence Hicks

THE labor policy, of the Standard Oil Co. (New Jersey) is founded. first of all on paying at least the prevailing scale of wages in the community; on, the eight-hour day, with time and one-half for overtime; one day's rest in seven; sanitary and up-to-date working conditions; just treatment assured each employee; payment of accident benefits beyond the amount prescribed by the State compensation law; health supervision by a competent medical staff; payment of sickness benefits after one year's service; cooperation with employee in promoting thrift and better social and housing conditions; and assurance for a generous annuity at the age of 65, guaranteed for life after 20 years of service. Most of these features have been a part of the company's policy for many years, but it is only during the past two years that the cooperation of employees in determining these matters has been definitely assured through industrial representation. Industrial representation, in the Standard Oil Co., is a principle rather than a procedure. It is built upon the belief that personal association of those interested in any problem leads to a mutual understanding and a fair decision as to what is right. Fully believing in this, principle, representatives of employees and representatives of management evolved a simple plan, the basis of which is that it gives every individual employee representation at joint conferences on problems and fundamental principles affecting all those interested in the industry. It is based on cooperation, not antagonism; its operation makes perfectly clear both to management and to employees that their interests are identical, that mutual understanding and cooperation insure progress and success for all. Furthermore, experience has definitely shown that representatives of the employees are not only alert for the employees' interests but are as keen as the representatives of the management in determining and insisting upon fairness to the employer.

Jan 3, 1920

By James E. Lonergan, Young C. Kim

Over the past two and one-half years, various emission control strategies for a coal-fired power plant have been jointly developed by the University of Arizona and the Homer City Owners. The objective of this work was to assist the Homer City management in their efforts to comply with SO2 emission regulations while continuing to use the relatively high sulfur coal from their captive mines as the primary source of plant fuel. One of the operational strategies studied was to have the captive mines minimize the sulfur variability of the run-of-mine coal on a short term basis. A mine production scheduling program called COMPF2 was developed to perform this task. This paper describes the application of this mine planning program at an underground coal mine. A comparison of the planning results with actual production figures showed the ability of this program to schedule production so as to minimize both the sulfur content and the sulfur variability of run-of-mine coal.

Jan 1, 1983

By Klaus Schoenert

In the analysis of comminution processes, it is necessary to have a detailed knowledge of such subprocesses as: transportation of the particles to the zone where they are stressed; the stressing of particles to a level high enough for breakage; removal of the fragments that are smaller than the limit size from the grinding zone; and prevention of agglomeration of the fine fragments. Breakage phenomena of particles is the most difficult subprocess to understand. It can be understood only by applying the principles of fracture physics to obtain information about the stress-strain field in particles which are loaded either by compression or by impact, and by using this theoretical knowledge to interpret experimental results obtained from single particle crushing studies. Two important features of the "Science of Communition" are discussed: the fracture physics and crushing under controlled conditions with special reference to single particle crushing, packed bed crushing, measurement of energy needed for fracture, fragment size distribution, and new surface area produced. The important features of these aspects are detailed, namely, energy balance of a crack, influence of environment, specimen size problems, and energy utilization in single particle crushing.

Jan 1, 1973

By A. F. Daily

Free World consumption of diamonds of all types closely follows the fluctuations of the business cycles in the large industrialized countries, particularly the U.S. Sustained purchasing by this country for stockpiling purposes has been a major factor in Free World demand for crushing bort and industrial diamonds, and it has been for this reason that investments in larger plants have been made by all major diamond mining companies during the past few years. For the purposes of this study, the diamonds produced in the Congo and elsewhere in the Free World are divided into three types:

Jan 5, 1961

By P. W. Allen

Here are the facts and the figures on how Tahawus cut costs and improved safety in solving their secondary breakage problem - A dropball crane entirely eliminated secondary blasting.

Jan 4, 1953

By G. M. Roberts

During the six years that the writer was connected, as chemist and chief assayer, with the Proprietary Mines, Broken Hill, N. S. W., several interesting experiments were made in the sampling of the silver-lead bullion obtained from the waterjacket smelting-furnace.

Jan 1, 1899

By K. V. S. Sastry, S. C. Panigraphy, D. W. Fuerstenau

The batch balling behavior of hematite, magnetite and limestone was found to depend markedly on the grinding method used for feed preparation. Wet ground materials require higher moisture for balling than do dry ground materials. Further, as the fineness of the wet-ground material is increased, the overall rate of agglomeration decreases, whereas the opposite is true for dry-ground materials. In contrast, the resulting pellet size distributions are not affected by the nature of the feed material preparation. These differences and similarities in the agglomeration behavior between wet and dry ground materials may result from the hydrophilic/hydrophobic nature of the surfaces, the formation of pre-agglomerates during dry comminution, and possible variations in the packing density of particles in the agglomerates.

Jan 1, 1978

By Gordon R. Haworth, J. Terry Aimone

The capital-short mining industry, faced with weak metal markets, will need to devise new and novel methods to finance future expansions.

Jan 9, 1977

By S. R. Bardsley, S. T. Algermissen

Induction, nuclear and sonic well-logging methods were employed in a Green River formation oil-shale analysis and evaluation study conducted in northeastern Uintah County, Utah. The physical and chemical properties of an oil-shale section, previously cored and assayed by conventional methods, were used to evaluate the response of the various logs. The logging program was designed to measure variable properties of oil shale which relate to oil-yield potential in order that a relationship between assay-oil yield and log-determined properties could be identified, thereby permitting a direct determination of yield potential from logs alone. All of the major oil-shale zones and section ttlarkers are recognizable on the logs used in the study. The relationship between the response of the Density and Sonic logs and the assay-oil yield in gallons per ton was suficient to perinit the derivation of equations expressing the relationships. These equations can be used to determine the potential oil yield in gallons per ton of an oil-shale zone or section. The Neutron log response distinguishes the rich oil-shale intervals from the lean intervals, but does not appear to permit establishment of a quantitative relationship. The Garnma-Ray and Induction logs indicate only a qualitative relationship to oil-shale yields. Logging oil shale by Gamma-Gamrna Density and/ or Sonic logging methods will permit a fast, economical and accurate means of evaluating the potential yield of oil-shale deposits. Considerable sums of money have been allocated to Green River formation oil-shale evaluation during the past years by both private enterprise and Federal and state governments. The result of the work accomplished to date is commendable, but the task of fully exploring and evaluating one of the world's greatest reserves of potential energy for economical exploitation is enormous and much information is still needed. Present methods of evaluation consist primarily of sampling and assaying the oil shale for potential yield. The data received are excellent, but are both costly (inasmuch as it requires funds specifically allocated for the evaluation purpose) and time-consuming (as each representative sample must be assayed in the laboratory by specially trained personnel). At the present time, the Green River formation oil-shale province is one of the most active areas in the Rocky Mountain region for exploratory oil and gas drilling. This activity could play a twofold role and serve the function of spear-heading many oil-shale evaluation programs, as it could provide both cutting samples for assaying, geophysical data and modern well logs. This paper deals with a recent study conducted on Green River formation oil shale in which the application of induction, sonic and nuclear well logs to oil-shale evaluation was tested and proved. THEORY AND DEFINITIONS Oil shale may be described as siliceous marlstone, rich in solid organic matter called "kerogen". Kerogen is only slightly soluble in organic solvents, but it will decompose and yield oil vapors and gas when heated to destructive distillation temperatures at about 800 F. The mineral constituents of Green River formation oil shale are found in essentially uniform proportions with one another. The dominant types are, in the general order of abundance, dolomite, calcite, feldspars and quartz. Kerogen is also essentially uniform in its composition, and is about 80 per cent carbon and 10 per cent hydrogen by weight. The ratio of kerogen to the mineral constituents determines the richness or potential yield of the oil shale. This ratio also determines the total physical and chemical properties of the rock and provides a basis by which oil-shale richness may be determined from well logs. Because Green River formation oil shale was deposited in a lacustrine environment, the lithology is laterally consistent over wide areas. The vertical section consists predominantly of thin bands of alternating rich and lean oil shale which have been described by Bradley' as varves. The varves are occasionally broken by thin bands of volcanic ash and tuff and by zones of lean vugular oil shale. The effect that the thin non-oil shale beds and vugular zones would have on the well log analysis was a prime concern in the study. To cope with this possible problem, the logs used in the study were of two types: (1) logs believed to respond favorably to those properties of oil shale which are dependent upon the kero-gen-to-mineral ratio, these logs being the Gamma-Gamma Density log, the Sonic log and the Neutron log; and (2) logs that would respond to litho-logies and properties within the oil-shale section not associated with yield that might result in anomalous responses by the yield-measuring logs. Logs of the second type were the Gamma-Kay log, the Induction log and the Caliper log. THE PRESENT STUDY The present logging study was con-

By Geoffrey Gilbert

The Montana Phosphate Products Co., subsidiary of the Consolidated Mining and Smelting Company of Canada, operates three phosphate properties north and northeast of Garrison, Powell County, Mont. Production of all three is from the same phosphate bed, a 3 to 4-ft. member of the Phosphoria formation, whose outcrop is traceable across the mountains of the Garnet Range in a series of southeasterly pitching folds. Because of topographical differences and of variations in the attitude of the bed, each property has its own mining methods and problems. Most of the phosphate rock produced since 1930 has been shipped to the plant of the Consolidated Mining and Smelting Co. at Trail, B.C., where it is treated with sulphuric acid for conversion to phosphoric acid, which in turn is used to produce various fertilizers. History The occurrence of rock phosphate in Montana has been known since 1910, and the Garrison area was mapped by the United States Geological Survey in 1913. In the nineteen twenties William Anderson, owner of a ranch 8 miles north of Garrison, discovered phosphate on his land, and the Montana Phosphate Co., which later became the Montana Phosphate Products Co., was formed to work the deposit. Montana Phosphate Products Co. later obtained United States leases on two adjoining parcels of ground, and this combined property, known as the Anderson mine, has been the main source of Con-solidated's phosphate rock. The mine now includes an adjoining parcel leased from Anaconda and mined from the Anderson workings. In 1940, the Graveley mine, a small privately owned property 6 miles east of the Anderson, was leased from the owner by Montana Phosphate Products Co., and a U. S. lease held by Graveley on some adjoining ground was subleased. In 1943 the Luke mine, on the Mineral Hill property, 1 3/4 miles south-southwest of the Graveley, a U. S. lease, which previously had produced a few thousand tons, was optioned from the lessees by Montana Phosphate Products Co., and is now being developed. At both these mines the rock is appreciably higher grade than at the Anderson mine. Geology The Phosphoria formation is the Permian member of an extensive sequence of Paleozoic and Mesozoic rocks. It is underlain by Pennsylvanian (Quadrant) quartzite and Mississippian limestone, and overlain without any marked unconformity by Jurassic (Ellis) shale and Cretaceous shale and sandstone. In the Garrison area, the Phosphoria itself consists mainly of about 50 ft. of gray to yellow chert. Immediately below the chert is the phosphate, usually 3 to 4 ft. thick. Below the phosphate occur a few

Jan 1, 1948

By Geoffrey Gilbert

The Montana Phosphate Products Co., subsidiary of the Consolidated Mining and Smelting Company of Canada, operates three phosphate properties north and northeast of Garrison, Powell County, Mont. Production of all three is from the same phosphate bed, a 3 to 4-ft. member of the Phosphoria formation, whose outcrop is traceable across the mountains of the Garnet Range in a series of southeasterly pitching folds. Because of topographical differences and of variations in the attitude of the bed, each property has its own mining methods and problems. Most of the phosphate rock produced since 1930 has been shipped to the plant of the Consolidated Mining and Smelting Co. at Trail, B.C., where it is treated with sulphuric acid for conversion to phosphoric acid, which in turn is used to produce various fertilizers. History The occurrence of rock phosphate in Montana has been known since 1910, and the Garrison area was mapped by the United States Geological Survey in 1913. In the nineteen twenties William Anderson, owner of a ranch 8 miles north of Garrison, discovered phosphate on his land, and the Montana Phosphate Co., which later became the Montana Phosphate Products Co., was formed to work the deposit. Montana Phosphate Products Co. later obtained United States leases on two adjoining parcels of ground, and this combined property, known as the Anderson mine, has been the main source of Con-solidated's phosphate rock. The mine now includes an adjoining parcel leased from Anaconda and mined from the Anderson workings. In 1940, the Graveley mine, a small privately owned property 6 miles east of the Anderson, was leased from the owner by Montana Phosphate Products Co., and a U. S. lease held by Graveley on some adjoining ground was subleased. In 1943 the Luke mine, on the Mineral Hill property, 1 3/4 miles south-southwest of the Graveley, a U. S. lease, which previously had produced a few thousand tons, was optioned from the lessees by Montana Phosphate Products Co., and is now being developed. At both these mines the rock is appreciably higher grade than at the Anderson mine. Geology The Phosphoria formation is the Permian member of an extensive sequence of Paleozoic and Mesozoic rocks. It is underlain by Pennsylvanian (Quadrant) quartzite and Mississippian limestone, and overlain without any marked unconformity by Jurassic (Ellis) shale and Cretaceous shale and sandstone. In the Garrison area, the Phosphoria itself consists mainly of about 50 ft. of gray to yellow chert. Immediately below the chert is the phosphate, usually 3 to 4 ft. thick. Below the phosphate occur a few

Jan 1, 1948

By Henry Hanson

A STUDY of the ore to be treated should be the first step in deciding on a machine for crushing or grinding. Coarse crushing is practically confined to the jaw and the gyratory crushers, the large-size jaw type being often employed in large installations as a primary crusher, followed by the gyratory type for secondary reduction. In small plants where mine-run ore is reduced in a single step, either of these machines will do the work. In intermediate and fine grinding, various machines are used. The relative merit of the different types will be governed in no small measure by the size of the installation, the character of the ore to be reduced and the final product desired for subsequent treatment. It should be possible, nevertheless, with the data available, if properly classified, to arrive at an approximation of the relative efficiency of these intermediate and fine grinders. It should be possible, also, to determine the economic grinding range of the different machines. With this in mind, it will be the object of this article to indicate, in rough outline, how the data available may be classified, rather than to attempt to discuss any particular practice and compare the results with other practices. Conclusions or generalizations can not be drawn without an exhaustive classification of data; in fact, many vital points will have to be determined by additional experiments which can be carried on most advantageously in the laboratory. The expense en-tailed in such experiments would be worth while if the data obtained should lead to definite conclusions that would aid in standardizing and simplifying grinding practice.

Jan 2, 1923

By J. Jolly

THIS short note on the probable character of the organic sulfur compounds in coal can do no more than indicate lines of research. We have no new experimental work to describe, nothing comparable in value with the careful studies of American coals by Powell and Parr1 and Yancey and Frazer.2 A study of the manner in which sulfur compounds exist in British coals (and their behavior on heat treatment) is rendered increasingly necessary by the fact that the British reserves of good coking coals of reasonably low sulfur content are fast being depleted. We believe that it is essentially by a study of the modes of formation, occurrence, and decomposition of the various types of inorganic and organic sulfur compounds in coal that it will be possible, with hope of success, to attack the problem of purifying coals, otherwise eminently suitable for coking, from these objectionable ingredients. Sulfur, so far as is at present known, does not normally occur in the free state in the coal conglomerate, but is chiefly distributed, irregularly, in three forms: 1. As primary constituents of the coal conglomerate, organic in nature and probably associated with those molecular complexes that have resulted from the degradation of the proteins of the plant tissues responsible for the formation of the coal mass. These constituents can be classed as "organic sulfur." 2. As metallic sulfides, e.g., iron pyrites. 3. As metallic sulfates, e.g., calcium sulfate and ferrous sulfate. (The occurrence of these compounds varies with the occurrence and degree of degradation of class 2.)

Jan 3, 1925

By AIME AIME

IN accordance with the provisions of Art. XII, See. 3, of the By-laws of the American Institute of Mining and Metallurgical Engineers, the Board of Directors hereby give notice of their intention to amend the By-laws as follows : Art. V, Sec. 2. Amend by substituting the word "senior" for ('first" before the words "Vice-president" in line two of the third paragraph of said section which relates to the calling of special meetings of the Board in the absence or disability of the President.

Jan 1, 1930