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REGULATIONS (proposed) for the location, drill-ing, casing, protection, operation, plugging and filling, and abandonment of natural gas and petroleum wells; having for their objectives. the protec-tion of life and property by prevention of intrusions of oil and gas into workable coal beds, and the conserva-tion of oil and gas resources in territory not underlain with workable coal beds. ARTICLE I Definitions Section 1.-For the purpose of these regulations (proposed), definitions are as follows: Well.-A bore-hole drilled for the purpose of developing natural gas or petroleum, or a bore-hole producing natural gas or petroleum. Well Operator.-Any person, persons, firm, partnership, corporation, company or association that proposes to, or does drill, operate, or abandon a well as herein defined. Coal Operator.-Any person, persons, firm, partnership, corporation, company or association that proposes to, or does operate, a coal mine in territory known or reputed to be underlain with oil or gas-bearing strata. State Mining Department.-The duly constituted authorities of a state having jurisdiction over coal-mining operations. Plat.-A map, drawing, or print made in accordance with the pro-visions of these regulations (proposed). Casing.-The pipe greater than 3 in. in diameter commonly used in wells drilled for natural gas and petroleum. Oil and Gas.-Synonyms, respectively, for petroleum and natural gas. Cement.-Hydraulic cement properly nixed with water only. Workable Coal Bed.-A coal bed in which, in the united judgment of the coal operator, the well operator and the State Mining Department, protection for life or property will be required when wells are drilled through it.

Jan 7, 1927

By Milton Fies

ALTHOUGH pig iron from iron ore and red cedar charcoal preceded the mining of coal by many years, for tradition says that Alabama iron was used to shoe the horses of Andrew Jackson's soldiers, coal was not produced until 1830. In that year, coal was mined in Tuscaloosa County, in the vicinity of what is now the University of Alabama, and shipped on flat boats (obviously during the wet season, for there were many shoals) down the Warrior River to Mobile. About that time, the first railroad, the Decatur & Tecumseh, was being constructed in northern Alabama to overcome the obstructions to freight traffic caused by the now well-known Muscle Shoals in the Tennessee River. This railroad was patterned after a railroad at Mauch Chunk, Pa., which was used for hauling anthracite from the Panther Creek valley. The Alabama railroad, which required about four years to complete, was 46 miles long and was used solely for the transportation of cotton. Although it was a failure, it demonstrated the practicability of the undertaking, and the succeeding railroads, which were begun in 1834, 1848, 1852, and 1853, added immeasurably to the development of the coal resources of the state. Between the years 1830 and 1860, practically all the coal mined in the state was dug from the outcrop near the river or from the river beds, and shipped by boat to Mobile. Transporting coal down the Warrior River was one of great risk, required much skill, and frequently had heavy losses. It is recorded that this coal was sold to the gas company in Mobile in 1844; it was most likely mined from the Black Creek Seam. In 1914, on the completion of Lock 17, the Warrior River became a navigable stream from 9 miles above Cordova, Ala., to Mobile and offers a great opportunity for the future development of the coal resources of the state.

Jan 9, 1924

By L. A. Schrider, J. A. Wasson

A method of predicting waterflood performance has been developed that combines certain facets of several previously published prediction techniques. The manner of combination has required the development and use of some new and some little-known relationships and has eliminated several of the weaker assumptions inherent in the original individual prediction methods. This approach, which was designed for computer solution, has removed the necessity of referring to plotted curves and permits the analytical prediction of water flood performance for a five-spot well pattern in either homogeneous or stratified reservoirs. The Predicted values are expressed in common oilfield units rather than in abstract or dimensionless terms. The calculation procedure has been programmed in FORTRAN IV and the entire program listing is available to potential users.* Introduction Prior to initiation of secondary recovery of oil by waterflooding, the possibilities of economic success or failure must be evaluated with the greatest practical accuracy. Although many prediction techniques are available, most, if not all, have serious limitations. In recent years, the Bureau of Mines has attempted to stimulate interest in the secondary recovery of oil from Appalachian pressure-depleted reservoirs. Waterflooding, because of its widespread acceptance and success, is the principal secondary-recovery method considered. During the life of the project, several performance prediction methods have been studied and applied. Because these methods, individually, have inherent assumptions and limi-tations, portions of some of them have been selected and combined in an effort to eliminate such shortcomings wherever possible. We believe that the resulting technique is as accurate as the necessary available data will permit and that it has several distinct advantages over previously published methods. Development of the Method The fractional flow equation developed by Buckley and Leverett' from Darcy's law is the fundamental mathematical statement describing immiscible fluid-fluid displacement in porous media. A generalized form of this relationship, whose derivation is readily available in the literature, is The formation dip, a, is usually very small in those petroleum reservoirs being considered for pattern waterflooding in the Appalachian area. Therefore. in many cases. a has an almist negligible value. In addition, Ap, the difference between the density of water and the density of oil, is relatively small. For these reasons the gravitational term may often be neglected. Capillary pressure is a function of saturation, which is in turn a function of distance from the upstream boundary of the system or the injection well. In this study it is assumed that the frontal zone of the waterflooding (or zone of capillarity) has negligible length and that only those saturations in the water-swept zone at breakthrough and later are of interest. As the distance in a waterflood pattern is comparatively large and the change in water saturation with distance is usually small, the change in capillary pressure with distance is negligible. The simplified form of the fractional flow equation is appropriate, therefore, in this application. Three variables must be considered in determining that fraction of the total fluid flow that consists of water: the viscosity ratio, saturation, and relative permeability ratio.

Jan 1, 1969

By Arthur Boynton

IN THE preparation of this paper the writer has been influenced by the fact that descriptions of various means of cleaning blast-furnace gas have been published and that further descriptive treatment of the subject will probably be less interesting than a statement of conclusions with regard to preferable methods which have been reached by him as a result, of experience and observation in this country and also as a result of somewhat detailed investigation of the subject made toward the end of the year 1927 on the Continent of Europe and particularly in. Germany. Owing to various circumstances, including a cost of fuel that is extremely high in relation to the wages of labor, the German iron and steel industry has accumulated experience in gas washing which is as yet in part lacking in the United States of America. The paper begins with a statement regarding the economics of the use of blast-furnace gas, then considers the principle's and practices employed in its purification. USES OF BLAST-FURNACE GAS For many reasons having to do with the utilization of coke-oven and blast-furnace gases in steel manufacture and with the use of hot metal, the blast furnace is now usually a part of a steel-producing unit, which also includes coke plant and rolling mill. Therefore both blast-furnace and coke-oven gas are usually applicable to any of the iron and steel-making processes, including the generation of power, and their allocation in any given works should be considered as a single problem. The uses to which blast-furnace gas, either alone or mixed with coke-oven gas may be put, include the following: Regenerative Heating of Air for the Blast Furnace.-This is the oldest and metallurgically the most important of all uses. It is universally performed with unmixed blast-furnace gas and under proper conditions should require not over 23.5 per cent. of the total gas generated for a blast temperature of 1350° F. For Steam-raising Purposes.-This is almost universally done with unmixed blast-furnace gas. From the standpoint of quantity used, it is at the present time the most important application in American steel-works practice.

Jan 1, 1928

By T. H. Troller

FOR a long time propeller-type fans have been considered a very adequate means to move great quantities of air against small static pres-sures. They have been in use for this purpose in mines, as well as in other installations. For static pressures of over 2 or 3 in. of water, the centrifugal blower almost ruled the field until very recently. Some attempts were made to use a number of propellers in line. Such arrange-ments made it possible to obtain pressures higher than 2 in. of water, but they complicated the construction and increased its expense, and the efficiencies were not improved. The more recent development of propeller-type fans has been decidedly influenced by the intensive aerodynamic research in connection with aeronautical development, which has taught us, in particular, how to use airfoils properly. The characteristic that makes an airfoil so valuable is the fact that when it moves through the air a high force component, the "lift," acts on it vertical to the motion, while the "drag" in the direction of the flow is small. The ratio of lift to drag is approximately 20 to 1 at the angles at which the profile is used in practice. An element of the turning blade, the movement of which, relative to the air, is mainly in the direction of the plane of rotation, thus experiences only a small "drag" FIG. 1.-DIAGRAM OF FORCES ON WING SECTION. opposing its rotation, and for this reason a relatively small torque is required at the driving shaft. At the same time there is a strong force component at 90° to the plane of rotation. This force is parallel to the propeller axis in the direction opposite to that of the flow of air, with a correspondingly high pressure increase.

Jan 1, 1936

By G. W. Bain

The Canadian magnesite deposits are situated in Grenville township, about 8 miles from Calumet station, on the Canadian Pacific Railway, but the poor transportation facilities have hindered their development. Magnesite was discovered in the boulders near White Rock Lake by Rev. W. P. Boshart in 1900. Observing that the material of these boulders was more glistening and whiter in color than Grenville limestone, he sent a specimen to the Department of Mines, Ottawa. An analysis showed this to be almost pure carbonate of magnesia and of commercial value if present in sufficient quantities. That summer, Boshart and McAllister found numerous outcrops, both of boulders and of bed rock, that gave promise of being magnesite of a commercial grade, and decided that this mineral deposit, if developed, would rival that at Veitsch, Austria. So they procured options on most of the land on which they knew the magnesite occurred. But the transportation difficulties were too great for the deposits to be mined at the prices offered for the product. In 1907, T. J. Waters organized the Canadian Magnesite Co. and opened a quarry on the north half of lot 18, range IX, and later on lot 15, range IX, of the same township. A lirnestone kiln was erected and the calcined rock was hauled to Calumet. In 1914, the North American Magensite Co, took over the quarries and shipped both crude and calcined magnesite until January, 1923. During 1915, S. Melkman organized the Scottish Canadian Magnesite Co. and opened a quarry on lot 15, ranges X and XI, Grenville township. A light, narrow-gage railway connects this quarry with the C. P. R. at Magnesite station. but shipments are made only during the summer months. Numerous other quarries have contributed to the output of the district but the greater part has come from the open pits of the

Jan 1, 1923

By G. W. Bain

The Canadian magnesite deposits are situated in Grenville township, about 8 miles from Calumet station, on the Canadian Pacific Railway, but the poor transportation facilities have hindered their development. Magnesite was discovered in the boulders near White Rock Lake by Rev. W. P. Boshart in 1900. Observing that the material of these boulders was more glistening and whiter in color than Grenville limestone, he sent a specimen to the Department of Mines, Ottawa. An analysis showed this to be almost pure carbonate of magnesia and of commercial value if present in sufficient quantities. That summer, Boshart and McAllister found numerous outcrops, both of boulders and of bed rock, that gave promise of being magnesite of a commercial grade, and decided that this mineral deposit, if developed, would rival that at Veitsch, Austria. So they procured options on most of the land on which they knew the magnesite occurred. But the transportation difficulties were too great for the deposits to be mined at the prices offered for the product. In 1907, T. J. Waters organized the Canadian Magnesite Co. and opened a quarry on the north half of lot 18, range IX, and later on lot 15, range IX, of the same township. A lirnestone kiln was erected and the calcined rock was hauled to Calumet. In 1914, the North American Magensite Co, took over the quarries and shipped both crude and calcined magnesite until January, 1923. During 1915, S. Melkman organized the Scottish Canadian Magnesite Co. and opened a quarry on lot 15, ranges X and XI, Grenville township. A light, narrow-gage railway connects this quarry with the C. P. R. at Magnesite station. but shipments are made only during the summer months. Numerous other quarries have contributed to the output of the district but the greater part has come from the open pits of the

Jan 1, 1923

By Ilmar Stöckel, Gösta Harlin, Agne Rustan

INTRODUCTION This chapter is a continuation of the studies by Rustan and Stockel (1979, 1980) on techniques for automating ventilation in Swedish mines and construction works. The studies have been financed by the Swedish Board of Technical Development. As a result of the studies it has been recommended that a good solution to diesel exhaust emission would be automatic, step by step control of the fans near the working place. Diesel vehicles are the major polluters underground in the mines. Therefore, we have suggested that diesel vehicles regulate the fans The goal of the continued study has been to find a way for active diesel vehicles to start and stop gallery fans at both intake and return air. In this paper different methods for activating fans are discussed. The best methods are chosen and tested in the mine. In this study we have found that change of temperature is an inexpensive and effective way to start and stop crosscut fans in sublevel caving and radio signals seem to be an attractive system for starting and stopping gallery fans . This work has been done in close collaboration between LKAB in Kiruna and the University of Luleå, Divisions of Electronics and of Mining and Rock Excavation. An advisory group for the project has been established with ventilation experts from the mines, representatives of the local mine workers' unions, and authorities from the local offices of Governmental Inspection of the Workers Safety. VENTILATION SYSTEM STUDIED In the project the ventilation system at LKAB in Kiruna was studied. The mining method used is sublevel caving with 9-13 m slice height. The air above ground is heated in winter by hot water and the main fans push the air down to a main distribution level along the 4000 m long and about 100 m wide ore body. From the distribution level, air is taken through shafts down to the sublevels, where it is pushed through the levels by local gallery fans on both the intake and return sides, Fig. 1.

Jan 1, 1981

By Floyd C. Kelley

The literature of the last decade is rich with information relating to the cause and means of control of grain growth in pure metals, but is deficient concerning the role diffusion plays in grain growth, although during this period many new products that depend on diffusion for their properties and success have been developed. Among these are cementation products, produced by calorizing, chromizing, and carbonizing, or by mixing, pressing, and sintering powdered metals such as Syke's iron-molybdenum die material, Genelite, and Elcon Metal (copper, tungsten) etc. This is a fertile field for new developments, but before it can be utilized to the fullest extent there must be a thorough invest,igation of the processes by which diffusion and grain growth take place. Grain growth plays no small part in the process and certainly the physical properties of these products depend largely on the grain size and state of equilibtiuni produced. The field of investigation does not end here, but may be extended to the effect of diffusion on impurities, segregations and dendrites in the broad field of ferrous and non-ferrous metallurgy. A number of years ago the author investigated several of these cases and noted, with striking regularity, the pronounced effect of diffusion in promoting recrystallization and grain growth. An example of this phenomenon is given in his paper on chromizingl which contained photomicrographs of large radial or columnar crystals produced by diffusion of chromium in the solid state. Another manifestation of this effect was discussed by Austen,2 who showed the part hydrogen plays in the decarburization of steel and the effect of diffusion upon the grain structure. Diffusion of Metals in Iron It seems to be a general law, whenever two metals are brought into intimate contact at a temperature at which diffusion takes place, that a comparatively rapid, or abnormal, grain growth results. The grains

SANTA Rita del Cobre Grant, as the present Chino property was known in the early part of the nineteenth century, was the scene of the first copper-mining operations of consequence in the territory now included in the United States. As early as 1801, the mines afforded the principal supply of copper for coinage by the Mexican Government. According to an estimate made from old records by H. A. Thorne, now superintendent of mines for the Chino company, about 41,000,- 000 lb. of copper had been produced prior to 1845, when the exploitation of the native copper deposits of the Lake Superior district was started for the first time by white men. B. S. Butler, in Mineral Resources of the United States for 1913, estimated the production from Grant County, New Mexico, from 1845 to 1913, at 134,353,963 1b.-an amazingly precise figure, considering the character of the data that he must have used. As "Grant County" may be interpreted for practical purposes as the Santa Rita district, it seems fair to credit the Chino group with a production of 165,000,000 lb. of copper prior to the time when the modern operations commenced. Unlike Morenci, which, by the way, lies only about 80 miles westerly across the Arizona-New Mexico line, Chino offers no problem as to when its production might properly be classified as coming from a Porphyry Copper. The time is definitely fixed by the starting of the new mill at Hurley in October, 1911. The interval from 1903 to 1913 had witnessed little production of any kind; and prior to that time operations had been confined entirely to the mining of narrow veins or lenses of ore assaying 10 to 15 per cent copper or even more. Such orebodies frequently are encountered today, when the electric shovels, working in broad daylight, eat away rock that once was buried

Jan 1, 1933

By Howard N. Eavenson

The mines of the United States Coal & Coke Co. are located in the Pocahontas coal field, in McDowell County, West Virginia. Twelve plants have been opened and equipped, of which, by reason of the present business depression, only nine are now in operation. These twelve plants serve eighteen mines; some of the plants having several openings, in either the same seam or in different seams, tributary to the same tipple. Only nine of these mines are now being worked at the plants in operation. Construction work was begun in 1902, and coal from the first three plants started was shipped in December of that year. An additional plant was opened in 1903, two in 1904, two in 1905, two in 1907 and the last two in 1908. On Jan. 1, 1915, the plants have been in operation an average period of 8.8 years. The rules of the company, which have been in operation since work was first begun, are similar to those in use by the H. C. Frick Coke Co. at its mines in Pennsylvania, in which " Safety First" was incorporated as early as 1907; and it has always been the policy of both companies to look carefully after the safety of their employees. Although the field is an extension of the old Pocahontas field, the mines, located upon a new branch railroad, are away by themselves, and, as is usual in such cases, the class of labor attracted at first was temporary in character. The rapid development of the mines required the employment of many new men and officials each year; and, while the accident record from 1904 to 1909 was as good as the average of the field, it was felt to be not as good as it could be made, and a determined campaign was inaugurated for preventing accidents of all kinds. Fig. 1 shows the tonnage of coal produced per fatality, both total and for inside accidents only, at our mines; the tonnage per fatality of all West Virginia mines, and of those in the Pocahontas field. The purpose of this paper is not one of congratulation on the results so far accomplished, since the operating officials are not at all satisfied that the maximum is in sight, to say nothing of its having been reached; but to describe the organization and methods that have produced these

Jan 1, 1915

By J. C. Fisher

C. S. Smith has described a method for measuring the relative values of different solid-solid and solid-liquid interfacial tensi0ns. When a polyphase alloy is held at an elevated temperature, individual particles of each phase adjust their shapes and minimize the interfacial energy. Wherever three interfaces meet, the dihedral angles are such that the three interfacial tensions, considered as forces, are in equilibrium. When the angles between three forces in equilibrium at a point are known, it is possible to determine any two in terms of the third. In this way ratios of interfacial tensions have been .obtained. The value of a given interfacial tension ratio was found to be independent of the alloy system from which it was determined. Smith also has employed the method when one of the phases is liquid. When equilibrium is reached with respect to In the course of work on grain growth in high purity aluminum a simple optical method was developed for detecting the presence or absence of preferred orientation in annealed specimens. The specimens were prepared by grinding, polishing and "deep etching." The etching reagent used for high purity aluminum has been described.* The resulting etch pits produced selective

Jan 1, 1949

Such are the rigors of climate and topography of western Tasmania, that much of the area has remained uninhabited. The mountains, rising to peaks above 5000 ft high, receive the winds out of the west and precipitate 110 in. of rainfall a year on this coast. The drenched forests have a primordial look with such unfamiliar trees as the tru-sassafras, blackwood, cheesewood, ti tree, and man tree ferns. Prospectors speak of the "horizontals," trees which, in the dense foliage, grow out flat. When the explorer climbs over them he does not come back to the ground but continues forward on dense vegetation with the ground many feet below. Gold was discovered by the intrepid prospectors of the late nineteenth century and stamp mills were erected in the vicinity of Zeehan and Queenstown. At Mount Lyell, mining began for gold in the ironstone capping. The familiar story, of course, is that copper was found beneath the gossan and it was this mineralization that lead to permanent mining operations. Two companies began mining at Mount Lyell and their history from 1893 to 1902 was marked by an unreasonable competitiveness, human perversity and technical difficulties. The North Lyell and Mount Lyell companies were mining copper ores within one mile of each other separated only by a ridge. Each company built its own railroad and harbor. For six years of struggle both companies tried to work out the metallurgical problem which was the key to profit. Although they didn't know it, the two ores were complimentary and could have been smelted together. North Lyell ore was strong in silica and weak in iron, whereas Mount Lyell was fortunate in having a first-class metallurgist in Robert Sticht, from Brooklyn, N. Y., who in 1902 successfully achieved pyritic smelting without the use of carbon fuel.

Jan 10, 1964

The plan for establishing relations of American industry with national labor on a definite basis so closely follows the channels of the efforts of Engineering Council, principally in the classification and compensation work, that it is of special interest to the engineering profession. The principles laid down under the following headings are about to he submitted to a referendum vote of the membership of the Chamber of Commerce of the United States. These principles were prepared by a special committee of the Chamber of Commerce after a long period of study of the entire subject of industrial relations. 1. Industrial enterprise, as a source of livelihood for both employer and employee, should be so conducted that due consideration is given to the situation of all persons dependent upon it. 2. The public interest requires adjustment of industrial relations by peaceful methods. 3. Regularity and continuity of employment should be sought to the fullest extent possible and constitute a responsibility resting alike upon employers, wage earners, and the public. 4. The right of workers to organize is as clearly recognized as that of any other element or part of the community. 5. Industrial harmony and prosperity will be most effectually promoted by adequate representation of the parties in interest. Existing forms of representation should be carefully studied and availed of in so far as they may be found to have merit and are adaptable to the peculiar conditions in the various industries. 6. Whenever agreements are made with respect to industrial relations they should be faithfully observed. 7. Such agreements should contain provision for prompt and final interpretation in the event of controversy regarding meaning or application.

Jan 6, 1919

By R. F. Mehl, W. Batz, C. Wells

L. S. Darken—It is indeed gratifying to find that the results of the two different methods here reported are in substantial agreement with each other and with the earlier work1 of two of the authors. Dr. R. P. Smith, of our laboratory, has been conducting some experiments at 1000°C to determine the diffusivity of carbon in austenite by a third method— the steady state method. This work, which will soon be reported, is far enough advanced that we can say it is in substantial agreement with that of the present authors. The only disparity which might be considered significant is in the high-carbon region, where we find that the diffusivity rises a little less steeply than indicated in fig. 8. F. E. Harris—The authors have presented an impressive arrangement of data concerning the diffusion of carbon in austenite. Of particular interest is the compilation, table IV, which is repeated in col. B of table V for direct comparison with values (col. A. table V) from a formulation using a single Q value of 31,000 cal as the activation energy for diffusion. This comparatively simple formulation has been used quite successfully in the practical application of calculating the carbon added (or removed) through the face in carburizing and decarburizing experiments, where the face concentrations are held quite constant for known times and temperatures. Literally hundreds of tests have been so checked where the computed and experimental values have varied by less than 5 pct. For higher temperatures, where proper carburizing data are hard to obtain, the diffusion couple is treated as a decarburization of the high-concentration bar and as a carburization of the low-carbon member. The analysis has been limited to a maximum of 1.40 wt pct carbon. The agreement between cols. A and B in table V may be considered fair, if a liberal viewpoint is taken. The use of a diffusion couple has one serious drawback, in that comparatively small amounts of carbon pass through planes of concentration close to those of the initial high-carbon and low-carbon members, and hence small errors become important. In addition to the sensitivity at these high and low concentrations.

Jan 1, 1951

By C. E. Cottrell, G. W. Preckshot, N. D. Delisle, D. L. Katz

Most crude oils contain asphaltic substances that may be naturally or artificially precipitated. In the Greeley field, California, this asphaltic bitumen is precipitated during the flow of the oil from the reservoir to the stock tank The mechanism of such precipitation is not well understood. This paper presents the progress that has been made by using the electron microscope as a new tool and by observing the effects of the streaming potential on the formation of bitumen particles. Crude oils at atmospheric pressure viewed in the electron microscope in very thin films under a vacuum showed no asphaltic particles. A technique of preparing slides of thin films by dilution of the oil with benzene and washing in petroleum ether was used at first, and these observations showed that the solvents caused the formation of the particles, varying from 0.01 to 0.2 micron in diameter. The electrical effects of fluids flowing through porous solid were studied, with emphasis on the formation of colloidal particles by the streaming potential. The streaming potential of crude oil flowing through sand was measured and was shown to be responsible for the formation of bitumen particles. These results bring out a new phenomenon, which may occur when crude oil flows through the porous oil reservoir. mechanisms. Asphalt has been the subject of widespread investigation but, owing to the complexity of the substances being considered, progress has been slow. Investigators working primarily with the asphaltic substances have treated the subject from the colloidal standpoint and have developed theories that picture the asphaltic particles as surrounded by adsorbed materia1s.14,15,17,24 The deasphaltization of lubricating oil by the use of solvents treats the subject primarily from the standpoint of liquid-liquid equilibria.'' A complete understanding of asphaltic substances would make possible the following of the material from its initial state in the crude oil through precipitation processes to the final plastic stage, the most common form of which is used in asphaltic pavements. Since these asphaltic particles are very small, it appears 'hat the electron microscope4 might be a useful tool in studying the precipitation processes. Specimens are examined by the electron microscope in a vacuum and as very thin films, requiring special techniques in preparation of samples. A brief description of the electron microscope and its operation will bring out the difficulties and advantages of its use for this problem. The first work was done with crude oils that had been diluted with solvents for the preparation of the film to be examined. Later a technique was developed by which the undiluted oil film could be made thin enough for direct examination. These two techniques show vastly different results Asphaltic particles have been precipitated from crude oils by a variety of

Jan 1, 1943

By G. W. Preckshot, C. E. Cottrell, D. L. Katz, N. D. Delisle

Most crude oils contain asphaltic substances that may be naturally or artificially precipitated. In the Greeley field, California, this asphaltic bitumen is precipitated during the flow of the oil from the reservoir to the stock tank The mechanism of such precipitation is not well understood. This paper presents the progress that has been made by using the electron microscope as a new tool and by observing the effects of the streaming potential on the formation of bitumen particles. Crude oils at atmospheric pressure viewed in the electron microscope in very thin films under a vacuum showed no asphaltic particles. A technique of preparing slides of thin films by dilution of the oil with benzene and washing in petroleum ether was used at first, and these observations showed that the solvents caused the formation of the particles, varying from 0.01 to 0.2 micron in diameter. The electrical effects of fluids flowing through porous solid were studied, with emphasis on the formation of colloidal particles by the streaming potential. The streaming potential of crude oil flowing through sand was measured and was shown to be responsible for the formation of bitumen particles. These results bring out a new phenomenon, which may occur when crude oil flows through the porous oil reservoir. mechanisms. Asphalt has been the subject of widespread investigation but, owing to the complexity of the substances being considered, progress has been slow. Investigators working primarily with the asphaltic substances have treated the subject from the colloidal standpoint and have developed theories that picture the asphaltic particles as surrounded by adsorbed materia1s.14,15,17,24 The deasphaltization of lubricating oil by the use of solvents treats the subject primarily from the standpoint of liquid-liquid equilibria.'' A complete understanding of asphaltic substances would make possible the following of the material from its initial state in the crude oil through precipitation processes to the final plastic stage, the most common form of which is used in asphaltic pavements. Since these asphaltic particles are very small, it appears 'hat the electron microscope4 might be a useful tool in studying the precipitation processes. Specimens are examined by the electron microscope in a vacuum and as very thin films, requiring special techniques in preparation of samples. A brief description of the electron microscope and its operation will bring out the difficulties and advantages of its use for this problem. The first work was done with crude oils that had been diluted with solvents for the preparation of the film to be examined. Later a technique was developed by which the undiluted oil film could be made thin enough for direct examination. These two techniques show vastly different results Asphaltic particles have been precipitated from crude oils by a variety of

Jan 1, 1943

D. J. DEMOREST,* Washington, D. C. (written discussion ?).-This paper is a real contribution to technical science; it will make it' easier to think accurately about the inner workings of a blast furnace. I was rather surprised to read that the authors regarded as a new discovery the idea that a molten mixture of CaO, A1203, and Si02 is a molten solution of the compounds of these oxides rather than of the oxides in each other. Surely no. chemist with an active respect for the known facts of chemical affinity could believe that these oxides could be melted together without forming compounds, and that these compounds would then dissolve in one another. This work does, however, help to establish what it was supposed must be true. I think it is worth while, in the light of the work of the Geophysics Laboratory, this work of the Bureau of Mines, and that of previous investigators, to visualize what happens as a charge passes down through a blast furnace, thinking especially of the slag-forming materials. These are chiefly kaolin (Al203.2SiO2.2H2O), quartz, and limestone. These substances do not undergo much change until the limestone decomposes at about the middle of the furnace, whereupon the chemical affinities of CaO and SiO2 must begin to he active; especially if there is any amorphous Si02 present. This forms CaSiO3, and the SiO2, CaSi02 and Al2-032SiO2 then come together to form the binary and ternary eutectics so well located by the work of the Geophysics Laboratory. No matter how much lime has been charged into the furnace, the formation of this eutectic will start it about the same height in the furnace and the gangue will start to get pasty at the same height. If the charge is such that the

Jan 4, 1918

By D. W. Fuerstenau

The United States is rapidly approaching an acute shortage of minerals. According to some observers, this situation may even be more severe than the energy crisis because the US consumes nearly 30% of the world's mineral production. With the mounting competition for world mineral supplies, we can no longer take for granted that foreign mineral products will be available to the US as abundantly as in the past. In 1973, US consumption of mineral raw materials was $35 billion. Of this, $7 billion consisted of imports. Without a drastic reorientation towards the mining of domestic mineral resources, the 1973 $7 billion deficit might mushroom to $100 billion by the year 2000. Thus, a return to domestic sources of raw materials will become absolutely necessary-and will be bucking the trend of the past 25 years, characterized by capital investment for growth in multinational overseas mining operations.

Jan 11, 1975

By Daniel T. O’Brian

Mineral exploration activities are benefiting from new interpretive techniques which have become economically practical with computers. Government agencies, educational institutions, and industry have each contributed research and development efforts for improving the mathematical analysis and graphical display of exploration data, resulting in operational aids not foreseeable a decade ago. Progress has been worldwide and is expanding rapidly. Books 1-10 are supplementing the periodic literature, at least one abstracting service is now active, 11 and an association has recently been formed to encourage and publicize advances in this field. 12 With the diversity of applications, only partial coverage of the subject can be made at any single symposium. Four of the six papers in this section report on the current state-of-the-art in selected areas of interest: graphics, time-sharing, mathematics, and economic analysis. The remaining two papers are descriptions of advanced statistical techniques for gaining additional information during exploration, and illustrate methods which will become more commonly applied in the future. "Computer Graphics: A New Tool for Exploration and Mining" describes the use of a computer and accessory equipment as an information retrieval device, graphically merging and displaying pertinent information for visual inspection and interpretation. This is a rapid means of studying information which has been pre-stored in a form accessible to the computer. Time-sharing is a means of achieving a comparable rapid response when calculations are being performed. The paper, "Some Applications of Time-Sharing in Mining Geophysics," describes the experience of one company using a time-sharing facility for geophysical computations. Another paper on this subject, stressing mining applications, has recently been published. 13

Jan 1, 1969