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By Lawrence H. Van Vlack

DISCUSSION, H. L. Burghoff presiding C. S. Smith (University of Chicago, Chicago)—The author is to be congratulated on his valuable contribution to the extremely meager absolute data on interface energies in metallic systems. It is interesting to note that the ratio between a and r iron boundary energies is approximately the same in the quaternary alloy with silicon, carbon, and sulphur as in the binary Cu-Fe alloy. A value for the copper grain boundary energy can be obtained from the author's data, Tables IV and VI, by utilizing the energy ratios of the following pairs of interfaces: copper-sulphide/copper, copper y iron, y iron/y iron, y iron/ copper, and copper/copper. This gives a value of 595 erg per sq cm for the free energy of the copper grain boundary. Despite this circuitous route and the assumption that the y iron boundary is identical in alloys with and without sulphur and does not change between 1105" and 100O°C, this figure is in remarkably close agreement with other values of the copper boundary energy, obtained by equilibration against lead and against the free copper surface. It therefore appears either that impurities do not greatly affect the grain boundary energies or that boundaries in even nominally pure metals are already sufficiently contaminated so that further change has little effect.

Jan 1, 1952

By A. M. Gaudin, J. G. Morrow

FLOTATION requires the existence of a definite contact angle. This contact angle, the surface tension of the solution, and adsorption at the solid-fluid interface are quantitatively related. Adsorption of dodecylammonium acetate on hematite was measured for a wide range of concentrations of reagent in solution. Similar measurements for quartz have already been made. Contact angle measurements were then made on polished surfaces of hematite and of quartz immersed in aqueous dodecylammonium acetate solutions, and a functional relationship was sought between adsorption density at the mineral-solution interface and the contact angle. Finally, the surface tension of the aqueous amine acetate solutions was measured. These data were combined to give an evaluation of the work of adhesion for the three-phase system. Specular hematite was crushed and then ground dry in a laboratory porcelain mill, with flint pebbles, to pass a 200-mesh screen. The ground product was sized in a Haultain infrasizer, and one of the granular sizes (cone No. 3) was used in all adsorption tests. A hand magnet was used to remove magnetite and abraded iron. Quartz was removed in a Frantz isodynamic magnetic separator. The purified hematite was leached in aqua regia, washed with distilled water until the washings appeared free of electrolyte by conductance measurement, dried in a low-temperature oven, and stored in a pyrex container. The specific surface of the closely sized hematite was determined by the krypton gas adsorption method.' Three measurements gave an average value of 1350 sq cm per g. Chemical analysis showed Fe -69.37 pct, insol = 0.72 pct. The quartz used in the flotation tests had been prepared by Chang" for an earlier investigation. Demineralized distilled water was used for all test solutions. Dissolved salt content was of the order of 0.03 ppm, expressed in terms of sodium chloride, as estimated from conductance measurements. Dodecylammonium acetate was obtained from Armour & CO. in two forms, the unmarked compound and a preparation marked by carbon 14 in the hydrocarbon chain of the aminium ion. Specific activity of the active salt was 0.134 millicurie per g. The important physico-chemical constants for the primary amine salt have been reviewed by de Bruyn. The calculated effect of hydrolysis of amine salt on pH of aqueous solutions and the effect of pH on the distribution ratio of the alkylammonium ion to free amine are of particular interest. All other chemicals used in this investigation were of analytical reagent grade. A column method' was used for adsorption work. Attainment of equilibrium distribution in the adsorption column depends on the solid-solution contact time, hence upon the volume of solution passed. It was assumed that contact time required for equilibrium would be a maximum for the lowest reagent concentrations. On this premise it was demonstrated experimentally that the passage of 500 ml of solution through the mineral bed was adequate. An aliquot (1 to 5 cc) of the solution to be analyzed was transferred to a small pyrex cup and allowed to evaporate to dryness at room temperature; 4 or 5 mg of unmarked amine acetate were added to the dried sample and the cup and its contents were transferred to the combustion system for analysis. Evaporation at room temperature must be emphasized, as even slightly elevated temperatures result in loss of reagent. A laboratory model G Beckman pH meter equipped with a glass electrode was used to measure pH of amine acetate solutions. The technique of internal gas counting of radioactive carbon dioxide in a Geiger-Muller counter was used. Developed originally by Brown and Miller,- his method was adapted to the analysis of carbon-14 marked flotation reagents by Chang, de Bruyn, and Bloecher. nalytica1 method and procedures have been described in detail by Bloecher.' Contact angles were measured by the captive-bubble technique." The mineral specimens were carefully selected to avoid cracks and inclusions of other minerals. All specimens were mounted in plastic and polished to produce a smooth surface. The final polishing and contact-angle measuring

Jan 1, 1955

By H. J. Morel-Seytoux

The influence of patten, geometry on assisted oil recovery for a particular dispIacement mechanism is the object of investigation in this paper. The displacement is assumed to be of unit mobility ratio and piston-like. Fluids are assumed incompressible and gravity and capillary effects are neglected. With these assumptions it is possible to calculate by analytical methods the quantities of interest to the reservoir engineer for a great variety of patterns. Specifically, this paper presents (1) very brieily, the methods and mathematical derivations required to obtain the results of engineering concern, and (2) typical results in the dorm of graphs or formulae that can be used readily without prior study of the methods. Results of this work provide checks for solutions obtained from programmed numerical techniques. They also reveal the effect of pattern geometry and, even though the assumptions of piston- like displacement and of unit mobility ratio are restrictive, they can nevertheless be used for rather crude but quick, cheap estimates. ,These estimates can be refined to account for non-unit mobility ratio and two-phase flow by correlating analytical results in the case M = 1 and the numerical results for non-piston, non-unit mobility ratio displacements. In an earlier paper1 it was also shown that from the knowledge of closed form solutions for unit mobility ratio, quantities called "scale factors" could be readily calculated, increasing considerably the flexibility of the numerical techniques. Many new closed farm solutions are given in this paper. INTRODUCTION BACKGROUND Pattern geometry is a major factor in making water-fIood recovery predictions. For this reason many numerical schemes have been devised to predict oil recovery in either regular patterns or arbitrary configurations. The numerical solutions, based on the method of finite difference approximation, are subject to errors often difficult to evaluate. An estimate of the error is possible by comparison with exact solutions. To provide a variety of checks on numerical solutions, a thorough study of the unit mobility ratio displacement process was undertaken. To calculate quantities of interest to the reservoir engineer (oil recovery, sweep efficiency, etc.), it is necessary to first know the pressure distribution in the pattern. Then analytical procedures are used to calculate, in order of increasing difficulty: injectivity, breakthrough areal sweep efficiency, normalized oil recovery and water-oil ratio as a function of normalized PV injected.

Jan 1, 1967

By C. E. Lesher

THE Disco* process for the production of low temperature coke and its immediate predecessor, the Wisner or Carbocite process have been described in the voluminous literature of low temperature carbonization.1 This paper will describe the development of the process from the first attempt at commercial operation by the American Gas and Electric Co. at Philo, Ohio, Yn the 1920's to the successful operation in 1949 by the Disco Co., a division of the Pittsburgh Consolidation Coal Co., of the 1000-ton per day Disco plant near Pittsburgh, see Figs. 1-2. In the 1924 coal industry depression following the hectic post World War I expansion, the northern Appalachian, unionized bituminous coal fields were affected first and foremost, and Western Pennsylvania as hard as any. Competitive market pressure was heaviest on the lower grades of steam coals, notably the from the Panhandle district where ash and sulphur are inherently higher than in the same Pittsburgh coal bed to the east along the rivers. The firm structure of Panhandle coal while favoring the prepared sizes, depressed the usefulness and value of the finer sizes. Panhandle slack and nut slack were marketed with difficulty at consistent, and at times considerable, loss. Many solutions were suggested, and the Pittsburgh Coal Co. investigated all. Lower delivered prices through lower mine costs and more advantageous freight rates were obvious goals, but equally obvious were the difficulties of self attainment of either in any substantial measure. Selling Btu's in pipes was abandoned as an idea after a thorough study of the economics of distribution of what was then, and is even now, the only developed continuous process of complete gasification of bituminous coal-producer gas. Although the coal company purchased huge blocks of electric power, it sold not a car of coal to the central power stations. Public utilities controlled the markets for electric current, and it was found that no matter at how low a cost current might be put on the bus bars by the coal company, distribution to its widely scattered coal mines made such an enterprise practically impossible. Consolidation of underground operations and a huge modernization program of mining operations in the 1920's were but preparation for the introduction of mechanical cleaning of the coal for market, particularly the smaller sizes of steam, gas, and by-

Jan 1, 1953

By C. E. Lesher

THE Disco* process for the production of low temperature coke and its immediate predecessor, the Wisner or Carbocite process have been described in the voluminous literature of low temperature carbonization.1 This paper will describe the development of the process from the first attempt at commercial operation by the American Gas and Electric Co. at Philo, Ohio, Yn the 1920's to the successful operation in 1949 by the Disco Co., a division of the Pittsburgh Consolidation Coal Co., of the 1000-ton per day Disco plant near Pittsburgh, see Figs. 1-2. In the 1924 coal industry depression following the hectic post World War I expansion, the northern Appalachian, unionized bituminous coal fields were affected first and foremost, and Western Pennsylvania as hard as any. Competitive market pressure was heaviest on the lower grades of steam coals, notably the from the Panhandle district where ash and sulphur are inherently higher than in the same Pittsburgh coal bed to the east along the rivers. The firm structure of Panhandle coal while favoring the prepared sizes, depressed the usefulness and value of the finer sizes. Panhandle slack and nut slack were marketed with difficulty at consistent, and at times considerable, loss. Many solutions were suggested, and the Pittsburgh Coal Co. investigated all. Lower delivered prices through lower mine costs and more advantageous freight rates were obvious goals, but equally obvious were the difficulties of self attainment of either in any substantial measure. Selling Btu's in pipes was abandoned as an idea after a thorough study of the economics of distribution of what was then, and is even now, the only developed continuous process of complete gasification of bituminous coal-producer gas. Although the coal company purchased huge blocks of electric power, it sold not a car of coal to the central power stations. Public utilities controlled the markets for electric current, and it was found that no matter at how low a cost current might be put on the bus bars by the coal company, distribution to its widely scattered coal mines made such an enterprise practically impossible. Consolidation of underground operations and a huge modernization program of mining operations in the 1920's were but preparation for the introduction of mechanical cleaning of the coal for market, particularly the smaller sizes of steam, gas, and by-

Jan 1, 1953

By W. R. Crane

THE support of roof in mines is dependent largely on the character of the top rock and its occurrence. The formations overlying the orebed in the Birmingham district are sandstone and slate. The sandstone occurs in beds of sufficient thickness to constitute important elements in the system of support; the slate is relatively strong but is thinly stratified. The alternating beds of sandstone and slate furnish an excellent combination in that the former are strong and the latter are impervious; however, their continuity is broken by jointing or slip planes. The thickness, and consequent weight of the overlying formations, is important in so far as the size and arrangement of pillars are concerned but may be relatively unimportant, temporarily at least, as a factor in the support of the roof. The position of the respective beds of sandstone and slate, their relative thickness, and their inherent weakness because of the occurrence of faults and folds, may exert a predominating influence on their support in place, which is affected only in part by the weight of the cover. The only mine in this district that operates under a cover of approximately 2000 ft. (1900 ft.) is the Shannon so-called "twin slope," situated 14,000 ft. southeast of the portal of the No. 7 mine of the Tennessee Coal, Iron, & Railroad Co. The conditions in this mine indicate what may be expected in other mines when the same depth is attained; in fact the effect of pressure is shown in several mines that have not reached two-thirds of that depth. It is evident then that conditions affecting the support of roof will not improve but rather will become more difficult with the extension of the mines into the valley under a constantly increasing weight of cover. Further, the difficulties will probably be augmented by the occurrence of faults and other disturbed ground, the presence and position of which at present are largely unknown.

Jan 9, 1924

By Edward C. Jeffrey

The use of coke in metallurgy, to any important degree, dates from the middle of the 18th century. Its utilization came most opportunely for European civilization. The forests of Europe, except in the most remote and inaccessible regions, had been largely fed, in the form of charcoal, into the smelting furnaces. For a hundred years—the middle of the 17th to the middle of the 18th century—there .was a stationary condition of population corresponding to the exhaustion of European forests. This situation, which was particularly evident in Great Britain, was due to the fact that the forests had been depleted and the practical utilization of coke had not begun. The coking industry is essential for our metallurgical industries, which in turn are basal to healthy economic progress. But coke is of great importance, not only on its own account, but for its byproducts, which enter fundamentally into all the arts of peace and war. The dyestuff industry and the manufacture of explosives are intimately connected with one another, as was shown by the recent war. The subject of coking coal, therefore, is well worthy the serious attention both of practical industry and the scientific investigator. The most valuable coking coals, from the metallurgical standpoint, are derived from the coals of highest ranks. Coals, for example, that have a carbon ratio of from 70 to 80 per cent. yield the most valuable coke for the blast furnace. The difficulty of investigating these coals, however, is great, for they are rather friable and delicate and possess a high carbon content, which makes them difficult to manipulate. They present, on account of their high carbon content, a considerable degree of opacity when examined, in thin sections, under the microscope. The tenderness of structure and blackness of such high-grade coking coals as those of Connellsville and the Pocahontas region make them extremely difficult to investigate. Two of my colleagues, who are taking part in this discussion, will describe the valuable results that have been reached by studying coal by the methods of the mineralogist. Doctor White and Doctor Thiessen have studied the structure of coal as determined from thin sections that

Jan 1, 1925

By Walter C. Lawson

The primary objective in laying track in panel sections is to reduce the number of track laborers required. This is possible because the work is mechanized. Moreover, because the work is mechanized and each of the operations needs only a few men, and each is self-contained, the work can be carried on at night as well as in daylight; therefore, the method provides a means of preparing tracks on more than one shift. The laying of tracks in open pits and quarries in panel sections is not new but new methods have been made possible by the introduction of new types of equipment. The purpose of this paper is to describe the methods that are followed in the Morenci open pit. General Mining Operations Full-scale ore production at Morenci is about 50,000 tons daily. The normal yearly output of ore and waste is 32,000,000 tons, of which 30,000,000 tons is handled by rail haulage. This requires the building of approximately 47 miles of loading and other temporary tracks during a 12 months' period (Fig I). Broken ore and waste is loaded into 90-ton capacity dump cars with 5-cu-yd full-revolving electric shovels. Shovel banks are uniformly 50 ft high. They are blasted with churn drill holes and the broken material from a blast is loaded out with two shovel cuts, the first one being called (locally) the "splatter" cut and the second one the "clean-up" or "face-up" cut. When a shovel is making its clean-up cut, the loading track is about 70 ft from the toe of the bank and, under normal conditions, a bank is blasted against it without removing the track. It is thus evident that each track is used for two shovel cuts before relocation is necessary, inasmuch as a single position serves for both the clean-up cut prior to blasting and for the splatter cut following the blast. The normal advance of a solid bench by a single blast is 40 ft (Fig 2). Preparation OF Panel Grade In preparation of panel grades bulldozers and rooters are used for the bulk of the work and an auto-patrol road grader for the final stage. At Morenci, bulldozers have always been used for track-grade preparation, but before the introduction of the other two types of equipment grades were uneven and irregular at best, and always necessitated a big gang of track laborers to hand-block under the ties with rocks after a track was laid into place. High blocking also made poor track because of instability and caused frequent derailments. Under these conditions derailments were generally bad as re-railing became difficult. Much track was torn up and many tics broken in the process. The inadequacy of the hand-blocked track, together with the inefficiency of hand blocking, constantly pointed, to the desirability of reducing the amount of labor required, so various means were tried to improve conditions, such as wood

Jan 1, 1949

By E. S. Machlin

The alternate processes by which solute atoms can limit the migration of grain boundaries have been considered. At the lowest solute concentrations the controlling process is "mechanical breakaway" in which the solute atoms affect the driving force and not the mobility. In the next higher range of solute concentration, solute atoms are bound to the boundary and diffuse by boundary diffusion along cusps in the boundary developed at the solute atoms. In this region the boundary velocity is controlled by the component in the direction of boundary migration of the rate at which the bound solute atoms can diffuse along the boundary. At still higher concentrations, it is predicted that boundaries break away from the binding solute atoms by thermal activation. The specific behavior Predicted is consistent with the observations of Aust and Rutter. The most striking agreement between prediction and experiment is that obtained for a range of solute concentration in which the boundary velocity is inversely proportional to the cube power of the solute concentration. MaNY models have been devised for the atomic steps in the motion of a grain boundary. McLean1 has listed some of these models and Aust and utter' have evaluated these and other models. If there are

Jan 1, 1962

By R. Lingle, E. Hardin, M. Board, H. Pratt, W. Ubbes, M. Voegele, N. Barton

A 2 m. cube of jointed, Pre Cambrian biotite gneiss was subjected to uniaxial and biaxial loading at ambient and elevated temperature. The effects of different boundary conditions on the following rockmass properties were investigated: deformation modulus, joint stiffness, dynamic modulus, coefficient of thermal expansion, thermal diffusivity and conductivity, and joint permeability. Test conditions ranged between 0 and 6.9 MPa uniaxial and biaxial load, and 12° to 74°C mean block temperature. The tests were performed as part of the Office of Nuclear Waste Isolation program for evaluating site charterization test methods for measuring the hydro-thermal-mechanical properties of rock masses. The fracture flow experiments discussed in this paper were described in detail in a similar paper given to this symposium in 1981 (Voegele, 1981). DEFORMATION MODULUS Horizontal deformation measurements oriented parallel to the loading direction were made at the block surface. Several instrument types were employed: surface short-rod extensometers, bonded strain gauges, vibrating wire strain gauges and the Whittemore caliper strain gauge. Two vertical and two slant borehole extensometers measured vertical displacement. Loading history, especially during uniaxial loading, was critical to interpretation of observed deformation and fracture flow data. This important tendency has been observed in other large-scale laboratory (Bandis, 1980) and field tests (Pratt, et al., 1977). Excavation of the block resulted in minimal disturbance to the intrinsic condition of the sample. Even so, permanent, unrecovered "set" was imparted to the block beginning with the first low-stress biaxial load cycle to 3.45 MPa (Table 1). Unloading

Jan 1, 1982

By N. H. Fisher

Geographical Distribution 'he most important known deposits in Australia of what are commonly referred to as the beach-sand minerals are along the most easterly part of the Australian coast, between Southport, 17 miles north of the Queensland-New South Wales border, and Ballina, 50 miles south of the border, and most of the production has come from this area (Fig I). Smaller deposits are known to occur farther to the south at intervals for several hundred miles, and beaches have been worked at Yamba, 96 miles south and Woolgoolga, 150 miles south of the border and at Swansea, 60 miles north of Sydney. Important deposits have been shown to exist on north Stradbroke Island and others have been located farther to the north, as far as Tin Can Bay at the south end of Frazer Island. (Fig 2). Table I gives the list of operators with the location of their deposits and workings, their approximate maximum monthly capacity expressed in tons of heavy mineral produced by their concentrating plants before separation into individual mineral concentrates, their methods of mining and concentrating the minerals, and the products obtained. This table applies as of June 1948, but all the operators are remodeling or improving their plants and plant practices will be modified accordingly. In addition, active boring campaigns have been carried out by Alluvial Gold, Ltd., of Sydney, in the Cudgen-Cudgera area, and by Zinc Corporation Ltd., of Melbourne, on Stradbroke Island, and in other places. Physiography Submergence of the order of 100 to 200 ft at the close of the Pleistocene period left the pre-existing hills as promontories and the valleys as deep inlets. Wave action has built bay-bars and sandspits in a northerly direction from the headlands, and lakes and marshes have formed between these bars and the initial post-submergence coast line. These lakes and swamps have been or are being filled in by river-borne sediments or wind-blown sand. Beasley1 has presented evidence that suggests a recent emergence of the coast line of about 10 ft. The evidence for this belief is the presence of a black sand seam 1/3 mile inland and 17 ft above sea level (Fig 3), and although it is not entirely certain that this seam is of beach formation and owes nothing to windblown concentration, other evidence supports the suggestion of recent emergence. Such emergence would undoubtedly aid the formation of bars and sandspits and the easterly progress of the beach front, leaving a series of parallel dunes (Fig 4). This belt of north-south coastal dunes ranges up to 56 mile in width and as many as 15 lines of dune have been counted (Fig 3). The foredune is generally the highest, upto 25 ft high, and there is in many places a flat platform in front of the dune known as the berm. The dunes behind the foredune are lower and less well defined

Jan 1, 1949

By Virgil W. Carmichael

In the Fort Union formation of western North Dakota, eastern Montana and northeastern Wyoming there are immense tonnages of lignite and subbituminous coal that have not yet been evaluated in terms of present economic conditions. The general lack of detailed geologic and topographic maps of this region, coupled with a considerable interest in some of its deposits, has spurred the North American Coal Corp. to develop a rapid, economical method of producing its own maps on which to base a quantitative evaluation of the coal reserves involved. The techniques the company employs in this mapping and evaluation program are simple photogeologic and photogrammetric procedures that can also be applied to other exploration and mining work. The air photos, in addition to being used for photogeologic interpretation, have been successfully applied to locating drainage cuts, haul roads, and road metal deposits as well as for various property studies and general mine and reclamation planning. The present discussion will deal primarily with North American's photogeological reconnaissance method of mapping and evaluating relatively flat- lying to shallow-dipping coal beds with limited topographic control and a minimum of core drilling. The field tools employed under this method include aerial photographs and pocket stereoscopes, engineering levels, aneroid barometers, portable transceiver radios and core drills. Field information developed on the photos is transferred to maps for measurement of reserves and overburden. To date this method has been used to map and analyze nearly 6 billion tons of Fort Union lignite and subbituminous coal.

Jan 8, 1969

By A. C. JR. Boyle

I. INTRODUCTION THE geological field work of the Bully Hill district, upon which this paper is based, was begun July 1, 1908, and covered a period of three months. The time was found too short for a complete report and the district was again visited in the early part of July, 1912,. from which time detailed study of the locality continued until September of the same year. This paper is the result of observations made in the mines in the immediate vicinity of Winthrop, Shasta county, Cal., during these two periods of study. The preparation of this report has been greatly facilitated by various courtesies rendered the writer by D. M. Riordan, President of the Bully Hill Copper Mining & Smelting Co., and by John B. Keating and Herbert R. Hanley, managing officers actively in charge at the mines. The elaboration and further study of the notes and collections were carried on in the laboratories of the Departments of Geology and Mining at Columbia University, and the writer takes pleasure also at this point in expressing his acknowledgments to Profs. James F. Kemp, A. W. Grabau, Charles P. Berkey, and William Campbell, for advice and assistance. In order that one may appreciate at first reading the significance of some of the details which follow, and for the sake of clearness, a brief outline of the geological relationships is here given, together with certain conclusions which have been reached regarding the genesis. of the ores and the gypsum masses. In the Bully Hill mining district an associated series of Triassic lavas and tuffs, chiefly andesites, is preceded as well as followed by sediments. The entire system is tilted so that the original bedding planes dip in general to the southeast. The surrounding region has been greatly disturbed, and in the immediate vicinity of the mines close folding of the later sediments and extreme shearing of the igneous rocks locally is a striking feature. Into the nearly vertical shear zones have been intruded post-Triassic dikes of various rock types in the following order: alaskite-porphyry and andesite-porphyry. Outside the area under consideration diorite dikes are known, but they will not receive attention further than to note that' they, probably, represent a differentiation product of the same magma from which the other two dikes came. In this connection all the dikes have an important bearing on the origin of the ores and of the gypsum found in the mines.

Jan 1, 1914

By HUGH E. McKinstry

OPENING the sessions of the Mining Geology Committee, the program on postwar mineral controls drew a larger attendance than any other session of the entire meeting. In view of its general interest, the papers of this session, or a substantial portion of them, are printed elsewhere in this issue. Whether control of mineral resources can help to promote peace, how controls could be applied and to whom, are questions so far-reaching that naturally no pat answer was agreed upon. In fact the discussion took on something of the flavor of a debate between those who favor strict control and those who felt that attempting to ration nations in peacetime would defeat its own ends. Discussion from the floor emphasized the difficulties in administering any international control and the $64 question, that no one cared to answer, asked by a courageous young lady who was induced to mount the rostrum for the purpose, was whether the United Nations should exchange mineral controllers to police each other.

Jan 1, 1944

By AIME AIME

LEWIS EMANUEL YOUNG was elected a Director of the A.I.M.E. at the last Annual Meeting as a representative of District '4, including. Ohio, West Virginia, and western. Pennsylvania and New York. He also represents the Coal Division, in which industry lie has actively participated- for nearly twenty years. Dr. Young was horn in Topeka, Kan., Oct. 1, 1873, received mining degrees from Penn State and ,-Iowa. State, and a Ph.D., from Illinois. The first part of his professional life was spent in teaching first as instructor in mining at Iowa State, second .as professor of mining at the Colorado School' of Mines, third as director of the School of Mines and Metallurgy at Rolla, Mo., and finally he taught business

Jan 1, 1937

By D. L. Wood

This investigation was concerned with the aluminum-oxide particle dispersions, the mechanical properties, and the re-c,uystallization characteristics of some internally oxidized copper-aluminum alloys. Obserued hardness vaviations are in agreement with variations in oxide particle size revealed by electron metallographic studies. The increase in yield strength caused by internal oxidation is quite sensitive to matrix grain size and is accompanied by a loss of ductility, particularly at higher temperatures. Elevated temperature ductility is con-side,vably improved if major grain reorientation is accomplished by ve recrystallization prior to testing. The oxide particles offer a considerable restraint to softening during annealing after cold deformation. THE diffusion of oxygen under appropriate conditions into a suitable alloy causes solute oxide particles to be precipitated at an inward moving interface.1,2 Previous work has shown that the hardness

Jan 1, 1960

By J. M. Dumore

If in a vertical, downward miscible displacement, the transition zone between the displacing and displaced fluids is neglected, a criterion for stable displacement can be obtained by considering a small hypothetical protrusion of one of the fluids into the other. This criterion leads to the definition of the well-known critical rate, uc = kg p/p. The consideration is further extended by taking into account the transition zone that develops as a result of diffusion and mixing. A generalization of the previous criterion leads to the definition of another characteristic rate, the stable rate, which in actual miscible drives will be less than the critical rate. In such drives, the entire transition zone is stable at rates less than the stable rate. At rates between the stable and critical rates, the displacement is only partly stable, i.e. part of the transition zone adjacent to the displaced fluid is in an unstable position. From that part of the transition zone viscous lingers will develop. At rates greater than the critical rate the entire displacement is unstable and viscous lingers will develop more strongly. Results of laboratory experiments are in agreement with the expected behavior based on the theoretically deduced stability of the displacement. INTRODUCTION The simplest form of miscible drive in an oil-bearing formation is the injection of a fluid that is completely miscible* with the oil under reservoir conditions. In general, such a fluid, a solvent for example, is less dense and less viscous than the oil present in the formation. If it is injected into a horizontal homogeneous layer, gravitational forces will lead to the formation of a gravity tongue of solvent in the upper part of the layer and the adverse solvent-oil viscosity ratio will cause viscous fingers to develop. If, however, the solvent is injected up-structure into ,a dipping layer, gravity has a favorable effect, because it tends to keep the less dense solvent up-structure. Tongue formation and viscous fingering are consequently reduced and it is even possible that they will be suppressed completely. Viscous fingering and gravity tonguing are the consequences of the instability of the displacement. A stable displacement cannot result in growing viscous fingers and/or growing gravity tongues. Since large amounts of oil can be bypassed if there is viscous fingering and/or gravity tonguing, the stability of a miscible drive is very important with respect to the recovery efficiency of the drive. The stability is of particular importance in miscible-slug drives, as it determines how quickly the miscible slug between the displaced and displacing fluids will be distorted and broken up, after which the drive is no longer completely miscible. Stability is thus a most important factor in determining the success of a miscible drive, and it is considered that the aspects of stability considered in this paper will make a useful contribution to existing theories. Consideration is given only to vertical downward displacements, in which no gravity tongues can develop and which are therefore simpler than downward displacements in sloping layers. THEORY CRITERION FOR STABLE DISPLACEMENT Let us consider a vertical column of a homogeneous permeable medium saturated with oil. A solvent less dense and less viscous than the oil is injected at the top of the column at a constant rate; in the column the velocities of oil and solvent are assumed to be uniform. Diffusion and mixing of oil and solvent will at first be neglected, i.e. we assume that solvent and oil are divided by a sharp interface. An additional assumption is that the interface is horizontal. Continuity of pressures exists at the interface, because no capillary forces are present between the two miscible fluids. Consequently, at the interface (Z = I)):** Ps = Po - P-where Ps is the pressure at the solvent side and

Jan 1, 1965

By E. J. KENNEDY

THE annual dinner-dance was held in the large ball room of the Commodore hotel Wednesday evening. A total of 577 were seated at the dinner, over which President Eavenson presided as chairman and toastmaster. In introducing George C. Stone, the James Douglas Medalist, W. R. Ingalls outlined the former's association with the zinc industry. He said, in part In designing and building Palmerton, Stone erected a metallurgical monument and won the title of chief engineer of the New Jersey Zinc Co., with transferal to its New York office in 1900. There lie held forth in dignity, efficiency, and with appreciation until his retirement from active service in 1929. After a few years lie was diverted from the position of chief engineer for his company to the superior one of chief metallurgist and that gave to Stone his next big chance.... This was the conception of a research department and the ability to persuade his directors to adopt it. I shall not pretend to summarize the great things that afterward developed. I shall mention only the institution of the manufacture of lithopone in this country, the charging of the Wetherill furnace with briquets, the mechanicalization of the Wetherills, the accomplishment of continuous distilling, and most recently the introduction of reflux-refining.

Jan 1, 1935

Two separate but closely related projects now under construction on the St. Lawrence River- the Seaway and the St. Lawrence Power Project- are providing the impetus for what may become one of the most significant economic expansions in the Northeast. By 1959, or even earlier, electric power will be flowing from the largest single hydroelectric installation east of the Rockies. Simultaneously there will come into existence a great new commercial waterway which will provide cheap transportation from the farm and industrial heartlands of the U. S. and Canada to the markets and resources of the world. When the Seaway is completed, vessels with five to ten times the capacity of those now using the Canadian canal system will be able to move from the Atlantic Ocean to Lake Superior.

Nov 1, 1955

By H. P. Allen

The Achotla mill of the Cia. Minera de Penoles is of special interest in that it is one of the few still employing the chloridization process. The ore milled comes from the Suriana mine and consists of both oxide and sulphide, from neither of which can the gold or silver be extracted by a simple cyanide treatment. The mill was built in 1927, after several years of study in the development of the process1, and operated from December of that year until October 1930. Operations were resumed in February 1935, and have been continuous since, treating approximately 5000 tons per month, while the mine is getting up to full tonnage of 6500 tons per month. Transportation of Supplies The property is in Guerrero, Mexico, some 175 km. by airline southwest of Mexico City. The mill site is at Temisco (Fig. I), 8 km. from the Balsas River and 4.8 km. by aerial tram from the mine. At Temisco are the general office, shops, warehouses and laboratory serving both mine and mill. Here sufficient water is available either from a small creek running through the property or from the Balsas River, also convenient and ample storage space for the tailings. With the exception of the mine timber and a few native building materials which may be obtained locally, all supplies for both mine and mill are brought down the Balsas River from Balsas, the terminal of a Mexican National Railway line out of Mexico City. The method of transportation on the river is interesting. Rapids with very fast water are numerous, prohibiting the use of mechanically propelled boats. Those used resemble large, flat-bottomed rowboats some 22 ft. long by 8 ft. wide (Fig. 2). They are manned by two oarsmen sitting in the bow, each handling one large oar, and usually another man in the stern who, with his oar, assists in steering the boat, especially when the rapids are run. From 3 to 7 tons of freight are carried on each boat, depending upon the stage of the water, which governs also the time

Jan 1, 1939