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By W. A. Ver Wiebe

Spurred on by the very high demands for new crude supplies resulting from World War 11, the oil men of Kansas strained every effort in 1943 to find as many new pools as possible. In all, 1761 test wells were drilled, ,of which 895 were successful in finding new oil supplies and 32 in finding new gas supplies. The total number of wildcat wells drilled in Kansas was 577, including the so-called "extension wildcats," which are located less than 2 miles from production. As a result of the very determined effort to find new oil reserves, 49 of the wildcat test wells found new oil pools in western Kansas and 7 found new oil pools in eastern Kansas. There were 289 rank wildcat tests, and among these 28 were successful ventures. They are responsible for 26 of the new oil pools recorded for the year and 2 of the new gas pools recorded. The ratio of dry holes to producing wells among such rank wildcats is thus approximately 10 to I (289 dry and 28 good). This compares with a ratio of II: I in 1942 and 6:1 in 1941; the same in 1940 and 5:Iin 1939. With nearly all wells flowing to their maximum economic capacity, the total production for Kansas during 1943 reached a new high; that is, 107,700,000 bbl., compared with 97,000,000 during the previous year. Similarly, the amount of gas sold during 1943 made a new high point on the production curve. The total amount was 122 billion cubic feet, compared with about 98 1/2 billion cubic feet for the year previous. As usual, the large Hugoton field of south- western Kansas accounted for approximately half of the total gas production. Highlights of the Year Despite the fact that 56 new pools were found in Kansas during 1943, it must be admitted that the future reserves of the state have not been increased greatly. Most of the new pools seem to be of minor value, although it is admittedly impossible to gauge the future production of any pool in Kansas with any exactitude. Judging by the later performance of some of the pools found in 1942 and in 1941, less than five of the new pools are likely to make any great contribution to the state's future oil reserves. Taking up the counties of Kansas in alphabetical order, the following statements summarize the highlights of the year. In Graham County, the Morel pool was extended to the southeast and this pool now promises to become one of the important pools of western Kansas. Several of the older wells have already contributed more than I000,000 bbl. of oil, and such a figure is considered very satisfactory in Kansas. In McPherson County, important new reserves were found by persistent drilling in township 17 S., R. I. W., the most northeastern township of the county. Many new wells in older pools and discovery wells in new pools make this region look promising. The Lindsborg pool, which had a sensational revival during 1942, was also extended in a number of directions and has now become a rather large producing area with a fairly high future potential capacity.

Jan 1, 1944

By O. R. Wagner, R. O. Leach

Immiscible displacement tests were performed in a consolidated sandstone core over the interfacial tension range from less thdn 0.01 to 5 dynes/cm to better define how interfacial tension (IFTJ reduction can lead to increased oil recovery. Data obtained were displacement efficiency at breakthbrough vs IFT for both drainage and imbibition conditions. These tests simulate water flooding under oil-wet and water-wet conditions, respectively. Results of the study have shown that displacement efficiency under both oil-wet and water-wet conditions can be markedly improved by a sufficient reduction in IFT. In the particular porous media used and for the low pressure gradients employed, the IFT must be reduced to a value less than about 0.07 dynes/cm to achieve increased recovery at the time of breakthrough of the injected phase. Below 0.07 dynes /cm, further small reductions in IFT result in large increases in displacement efficiency. Observed increases in recovery were obtained at pressure gradients which are well below those which can exist in the interwell area of a reservoir under water flood. The effect of pressure gradient on recovery is discussed. INTRODUCTION A residual oil saturation remains in rock which has been water flooded because, under usual reservoir conditions, the driving force which can be generated is inadequate to expel oil trapped by capillary forces. Since these capillary forces can be reduced by reducing the IFT a frequently studied method of increasing oil recovery has been the use of surfactants to reduce the water-oil interfacial tension. Mungan l observed improved recovery in both water-wet and oil-wet systems at 1.1 dyne /cm IFT, finding that the amount of improvement was greater in oil-wet systems. Moore and Blum,2 working with visual flow cell micro-models, con- cluded that recovery cannot be improved in water-wet systems by injecting surfactant solutions. They calculated that, for a pressure gadient of 1 psi/ft in their model, the IFT must be reduced to 0.03 dynes/cm to release oil trapped under water-wet conditions. Berkeley et al.3 indicated that, at representative field flooding rates, the IFT must be reduced to 0.001 dyne/cm to improve recovery, Thus, there is a wide variation of opinion about the IFT levels needed to improve recovery under field conditions. These previous investigators all have used as their experimental method the addition of surfactants to the injected water. The use of surfactant solutions to reduce IFT creates two experimental problems: (1) the loss of surfactant through adsorption on reservoir rock can obscure the true IFT value which exists at the displacement front, and (2) at very low values of IFT emulsifica-tion of oil and water commonly occurs. It is difficult, therefore, to determine whether the increased recovery is caused by IFT reduction as such, or is instead caused by emulsification. Also the properties of the available surfactants limit the IFT range which can be studied. In the present study the purpose is to better define how interfacial tension reduction can lead to increased oil recovery. A matter of great interest is the amount of recovery improvement potentially achievable in this way. The study was made using very low pressure gradients which was well within the range achievable by water flooding in the interwell region of petroleum reservoirs. A unique experimental approach was chosen to avoid adsorption and emulsification problems, and to allow convenient control of IFT. The fluid phases used were the equilibrium vapor and liquid phases of the methane-n-pentane system. The interfacial tension level was varied by changing the equilibrium pressure of the methane-pentane system over the range from 1,200 psia to near the critical pressure (2,420 psia). All tests were performed at a controlled temperature of 100F. The IFT-vs-pressure relationship for the methane-pentane system was based on the data of Stegemeier and Hough,6 and on new data obtained in this study. With this experimental approach it has been possible to study displacement at lower values of IFT than have been previously investigated.

Jan 1, 1967

By GUY C. RIDDELL, Donald M. Liddell

THE electronic arts today constitute the outstanding development in the field of rare metals, if not indeed in the arena of scientific progress at large. The year 1930 may become known as the year in which the electronic tube took hold of the wheels of industry; it is the year in which the tube's emancipation from the art of communication was proclaimed. The little tube which made a $500,000,000 industry out of a vacuum has now been applied to mining, manufacturing, transportation, chemistry, and other industries. Not many appreciate the extensive utility that e1ectroni.t tubes have already found in transportation, where they control the speed and security of express trains, as well as operate traffic lights on important highways-in the case of the Detroit-Windsor bridge counting the traffic and instantly turning the reports into the superintendent's office some distance away. In an Ohio steel mill, ten-ton ingnts 'rash back and forth through the rolls, reversed by their own shadows. The vacuum tube also starts, stops, and levels, fast passenger elevators.

Jan 1, 1931

By R. H. Tien

The accuracy of the method of steady-state approximation applied to the problems of heat transfer involving phase change (London and Seban's solution) is improved by defining a "modified heat of fusion" which accounts for the effect of specific heat. An analytical expression for this modified heat of fusion is derived in terms of the actual heat of fusion, specific heat, and surface temperature. Numerical solution for the freezing of iron indicates that the ratio of the modified heat of fusion to the actual heat of fusion increases from 1.04 to 1.4 as the surface temperature decreases from 2700° to 1600°F. The heat transfer process accompanying solidification is complicated owing to the moving solid-liquid interface where the latent heat of fusion is released. Exact analytical solution is available only for a few special cases of freezing problems such as Stefan's1 problem. In a commonly used steady-state approximation method, London and seban's2 solution, the effect of specific heat is neglected. This approximation, however, may introduce some degree of error in mathematical analysis when the temperature of the solid surface is much lower than the freezing temperature, as in the case of freezing metals. In a recent work by Robertson and Schenck,3 the problem of freezing a semi-infinite region with finite surface conductance was programed in a digital computer through the finite difference method. A family of curves for the correction of the London-Seban solution was given in a dimensionless plot for different ratios of heat of fusion and specific heat effect; it was shown that the London-Seban solution when applied to the freezing of a mild steel slab under some particular conditions gave results in error by about 10 pct in the solidification rate. Although the Robertson-Schenck computer result has improved the London-Seban solution to a great extent, lack of generality and the tedious computing procedure have restricted its application. In this paper a "modified heat of fusion" which accounts for the effect of specific heat is defined, and is used instead of the actual heat of fusion in the London-Seban solution. An analytical expression of this modified heat of fusion in terms of the specific heat, surface temperature, and actual heat of fusion is derived by comparing the solutions of Stefan and London-Seban for the case of freezing of a semi-infinite region with constant surface temperature. It can also be extended to the case with finite surface conductance, and the results show good agreement with the Robertson-Schenck computer solution. The expression of the modified heat of fusion, the accuracy of the London-Seban solution, and the temperature distribution within the solid are presented graphically in dimensionless form. Numerical solution for the freezing of iron indicates that the ratio of the modified heat of fusion to the actual heat of fusion increases from 1.04 to 1.40 as the surface temperature decreases from 2700° to 1600°F.

Jan 1, 1969

By R. J. Wagner, G. H. Gronhovd, A. J. Wittmier

The paper describes the results of a series of full-scale boiler tests run to determine the ash fouling characteristics of a North Dakota lignite as a function of sodium content of the coal. Four levels of sodium were investigated and rate of fouling was determined both by boiler performance and by specially constructed probe equipment. Discussed is information on chemical and physical properties of the ash deposits. The vast lignite deposits in North Dakota are becoming increasingly important as a source of low-cost fuel for power generation. A new 200-megawatt lignite-burning plant located near Stanton, N.D., was placed in operation early in 1966. Another 172-mega-watt unit in the same area is scheduled for operation late in 1966, and plans have recently been announced for a 212-megawatt unit to be in operation by 1970. If these plants show good performance, western North Dakota could become a major power production center for a large geographic area in the upper midwest. One of the problems associated with the use of lignite in power boilers is its tendency to form troublesome ash deposits on boiler tube surfaces. This problem varies considerably from one lignite-fired boiler to another and is dependent upon such factors as source of lignite, boiler design, load factor, tube metal temperatures, and soot-blowing practices. This report presents data on sodium content* variation in a North Dakota mine, describes the results of a series of tests performed to determine the relationship between ash fouling tendencies and the sodium content, and tells how the mining company and electric utility have coordinated their operations to reduce the ash fouling problem. GENERAL BACKGROUND Until recent years it was generally assumed that North Dakota lignite from a given mine had qualities peculiar to that mine, but that within the mine, the lignite was quite uniform. In 1959, the Otter Tail Power Co. installed a 53.5-megawatt lignite-burning unit at its Hoot Lake plant, Fergus Falls, Minn. Shortly after the unit was put into operation, it was noted that at certain times under high load conditions, ash fouling problems were quite severe, but not consistent or predictable. Each time fouling occurred in the unit the position of the loading shovel at the mine was noted. Within two years it became apparent that there were certain areas in the Knife River Coal Mining Co. mine at Beulah, N.D., where the lignite apparently had a high fouling tendency for the Hoot Lake unit. Results from analyses of the coal did not show large differences in moisture percentage, ash percentage, heating value, or ash fusion temperature between the highly troublesome and less troublesome coals. After three years of operation, the troublesome areas had been quite well defined and the mining company started a procedure of bypassing these areas when load conditions at the plant were high and then returning to the troublesome areas to load the lignite during the summer months when peak loads were lower. It was noted that the lignite from the areas which caused severe fouling under high load conditions produced much less fouling at the lower summer loads. However, bypassing certain areas in the strip pit caused the mining company to disrupt their continuous loading schedule, which in turn upset their continuous stripping schedule and made for less efficient mining operation. Meanwhile, at the Hoot Lake plant, the number of soot blowers on No. 2 boiler had been increased from 30 to 55, and a very rigorous blowing schedule had been adopted resulting in soot blowers operating at least some part of 21 hrs per day. Fouling problems continued, with a resulting reduction in plant economy and reliability. During this period the Federal Bureau of Mines Coal Research Laboratory at Grand Forks, N.D., had initiated various research programs relating to the study of lignite ash and ash fouling problems. One project was a survey in which full seam samples were obtained from various locations in all the major

Jan 1, 1968

By A. W. D. Hills

This paper describes the development of a generalized integral-Wofile method for the analysis of heat transfer dwing solidification. The method is extremely flexible, and can be applied to a wide range of situations. This flexibility has been achieved by characterizing the solid metal layer in terms of two parameters, and by developing two simultaneous nonlinear differential equations for these parameters in terms of the heat fluxes crossing the boundaries of the solid layer. The use of these equations is illustrated in a series of examples which involve the solidification of pure metals at zero superheat cooling under different conditions. The simplicity with which the method can be extended to treat more complicated jwoblems is illustrated in a further example which involves natwal convection effects in the liquid metal. ThE rate at which molten metal solidifies in an industrial casting process, and the structure of the cast product, are both controlled by the rate at which heat can be removed from the casting. A knowledge of heat transfer rates is thus essential to the control of the process and to the control of the structure and soundness of the final casting. Heat transfer rates during real solidification processes cannot be predicted by formal mathematical techniques, however, because nonlinear boundary conditions are involved. Approximate methods are normally used, and these have included electrical and hydraulic analogue techniques, finite difference methods, and the integral-profile method. Considerable effort has been devoted to the development of the first two techniques, but the integral-profile method has been used very little so far. This is unfortunate because the method is capable of providing relatively accurate solutions for the heat transfer equation during solidification without involving large amounts of computer time. A further advantage of the method is its flexibility, although this is not apparent from the integral-profile solutions that have been developed to date. These solutions have been derived for the solidification of molten metal at zero super-heat under cooling conditions involving either a constant heat flux from the cooled surface;' a constant heat transfer coefficient at the surface,'-3 or a specified variation in the surface temperature.4,5 A generalized integral-profile method is presented in this paper which can be used to predict unidirectional solidification rates under a very wide range of more realistic cooling conditions. The use of the method is illustrated in a series of problems involving pure metals, or skin forming alloys, solidifying at zero super-heat. However, the principal advantage that this method has over the previous integral-profile methods is the ease with which it can be extended to treat more complicated solidification problems. This is illustrated by considering a problem in which super-heat is liberated from the liquid metal by natural convection during the solidification process. In the final section of the paper the generalized method is compared with previous methods used to predict solidification rates and its extension to more complicated solidification problems is briefly discussed.

Jan 1, 1970

* The greatest and richest iron ore body in the world was discovered by U. S. Steel in Venezuela in April 1947, and is disclosed for the first time in this issue (p. 178), One solid mountain of ore, Cerro Bolivar, will furnish more tonnage than the famous Hull Rust pit at Superior has, or can produce. Total resources are on the order of 2 billion tons plus. Big Steel is now moving with great speed on construction to bring out this ore, and 10 million tons are scheduled for shipment into Baltimore and Birmingham by late 1952. This ore will arrive at, Pittsburgh at a price lower than present natural ores from Superior. The Venezuelan properties will be completely mechanized. •U. S. Steel and independent companies are embarking on a taconite beneficiation program of tremendous proportions, which must be speeded to completion in the 1950's (see p. 185). By 1960 over $l.2 billion dollars will be spent on Venezuela, taconite, and Labrador to solve the United States iron ore crisis. In addition, U. S. Steel will spend another $300 million plus for a new steel mill at Trenton, N. J., before 1955. •The Deister Concentrator Co. gave $500 to the 1950 Coal Division Scholarship Fund. •Howard N. Eavenson, in analyzing the bituminous coal situation (see p. 193), suggests that anti-trust laws be extended to labor unions, disinterested trustees to administer pension funds, begin pension funds now and stop the collection of all "check-offs" for union dues or funds. •Minerals and metals worth 13.9 million dollars were produced in the United States in 1949, Secretary of the Interior Oscar L. Chapman announced. Although this value was 11 pct less than in 1948, it was the second greatest in history. Nonmetallics was the only major group that in 1949 equaled the 1948 production high. Mineral fuels decreased 12 pct and metals 15 pct. • Prospects for making gas from coal are seen to be unattractive by the Pittsburgh Consolidated Coal Co. because the success of operation depends on price and supply of coal which presently are not attractive. The company has shut down its gasification plant at Library, Pa. * Economic prospects for the immediate future in the United States are good and business probably will continue at its present high levels throughout at least the early part of 1950, Secretary of Commerce Charles Sawyer said in his year-end report to the White House based on his personal survey of business conditions. •A 467-ft well 34 miles north of Rock Springs, Southwestern Wyoming, is said to be flowing a 5 pct solution of nearly pure trona (sodium carbonate) at the rate of 10,000 barrels a day. Trona, natural soda ash, is mined for the chemical trade at Searles Lake, Calif., and from about 1500 ft underground near Green River, Wyo., and has been in short supply. •The AEC is "very much interested" in a discovery of radioactive material that has been made in Baraga County bordering Lake Superior in the Upper Peninsula of Michigan, reported F. G. Pardee, Michigan State mining engineer. The material has been identified as uranium oxide in the form of pitchblende or uraninite. The discovery, made by a geologist of the Jones & Laughlin Ore Co., is the only instance in which the commission has certified samples of Michigan rock.

Jan 2, 1950

By R. H. Jacoby, V. J. Berry

Future depletion performance and ultimate oil recovery from reservoirs producing under volumetric control are often predicted with the aid of a material balance equation. When the reservoir fluid is very volatile, however, certain assumptions implicit in the use of the conventional methods are no longer valid. This is became laboratory differential vaporization test procedures do not adequately represent the reservoir depletion process and the performance of surface separation facilities. In such cases recovery of stock tank oil per unit of pressure decline can be predicted only from a detailed knowledge of the separator conditions and the over-all composition of the fluid entering the wellbore at each stage of depletion. Surface recovery is not simply related to the total quantity of liquid flowing into the well under reservoir conditions. In order to improve predictions for reservoirs which produce volatile oils, a step wise method of calculation has been developed. This method uses relative permeability data and multicomponent flash calculations to predict oil and gas production as a function of reservoir pressure. Calculations are presented for a reservoir containing a volatile crude oil, and predicted tank oil recovery by primary depletion is more than twice that predicted by conventional methods which are known to be adequate for ordinary black crude oils. Calculated maximum produced gas-oil ratio is less than one-fourth of the conventional prediction. Wellstream compositions have also been used to determine variation in stock tank oil composition and liquid content of the separator gas. This information is of particular importance for crude stabilization calculations and for design of gasoline plant facilities to recover LPG and natural gasoline. INTRODUCTION The estimation of oil reserves and the prediction of future recovery performance of petroleum reservoirs is a frequent task of the petroleum engineer. If the reservoir produces under volumetric control, performance calculations for primary depletion are made by combining oil and gas material balances with the gas-oil flow characteristics of the reservoir rock. For black oil reservoirs, the Schilthuis1 type material balance is commonly employed. For gas or gas-condensate reservoirs, where only one phase is flowing under bottom-hole conditions, a more simplified material balance is used. In the period in which these material balance methods were conceived and put into practice, it was common to classify reservoirs according to the type of fluid produced as (1) black oil reservoirs, or (2) gas or gas-condensate reservoirs. Recently, however, deeper drilling and more extensive studies of reservoir fluid properties have led to the recognition of reservoir fluids with phase characteristics between those of ordinary black oils, and gases or gas-condensate fluids. These intermediate fluids contain relatively large amounts of the hydrocarbons ethane through decane and are found in deep, high temperature (250°F) reservoirs. Such fluids are often referred to as high shrinkage crudes or "volatile oils." They are usually characterized by tank oil gravities above 45° API. high solution gas/oil ratios,

Jan 1, 1958

By E. D. Gardner

Apparently the widespread agitation for the codification of our mining laws has had its effect, and it is quite possible that Congress will take up the question during this present session. The greatest objection to our present statutes pertaining to metalliferous deposits seems to be directed against the law of the apex. Those who are not in favor of changing this law are very far in the minority and they apparently realize that it is useless to urge its retention. Next in importance to the repeal of the law of the apex, seems to be a widespread advocacy for the repeal of the law requiring discovery of mineral before a valid location of a mining claim can be made. To a lesser extent there appears to be a desire to have the law changed so as to allow patent for claims without mineral discoveries. The purpose of this article is to review the arguments in favor of the proposed change of the discovery requirement, to show some of the evils that may be expected to result therefrom, and to consider whether a system may be devised to correct the undesirable features of the present law in this respect and at the same time not expose the mining fraternity and the general public to the evils which would result from the repeal of this fundamental requirement. Under the law as at present framed, the validity of a mining location is dependent upon the fact of discovery of mineral within the boundaries of the land claimed. " * * * but no location of a mining claim shall be made until the discovery of the vein or lode within the limits of the claim located" (Sec. 2,320, U. S. Rev. Stat.). All authorities agree that discovery is the source of the miners' title. Lindley, in his valuable work on Mines (3d Ed., Sec. 335), lays down the rule in part as follows: "Discovery is the initial fact. Without that no right can be acquired. * * * Such discovery must precede the location, or be in advance of intervening rights. The proof of recording and marking a claim will not authorize the court to presume a discovery." As is well stated by the U. S. Supreme Court in Erhard v. Boaro (113 U.S. 536):

Jan 1, 1917

By B. R. Hollebone

The chemical action of molten anhydrous pyridinium chloride (pyridine hydrochloride) on oxy salts and ores of some Group IV and V metals are discussed-in particular zirconium, hafnium, niobium (columbium) , and tantalum. Laboratory-scale experiments are described whose results suggest that this reaction might provide a practicable means of converting ores of these metals to the anhydrous metal chlorides. Experimental results are given which provide some insight into the nature of the reactions and some of the compounds which could be present at intermediate stages. The treatment of ores of the more refractory metals is difficult and expensive and often demands the use of gaseous chlorine, hydrogen fluoride, or other reagents which are, if nothing else, expensive and dangerous to use. This situation is, of course, due to the strong metal-oxygen affinity resulting from the high charge and the small size of the metal ion which combine to produce such high lattice energy in the metal oxide as to defeat standard reduction methods. Thus, the characteristic of these metals which leads to one of their most important properties—corrosion resistance—is the main hurdle in obtaining the metal. Many common methods' for treating ores of zirconium and niobium (columbium), for example, proceed as directly as possible to the preparation of anhydrous halides. These halides are purified by now standard processes of solvent extraction, fractional distillation, and so on. This paper reports on preliminary stages in the development of a method of treating these ores—particularly of niobium—so as to prepare the anhydrous, volatile halides by the use of chemical reagents which are much more easily handled than those used at present. CHEMICAL PRINCIPLES The solvent action of aminium halides has been referred to periodically in the literature over several decades. The chemistry of pyridinium chloride has been discussed particularly by Audreith2 and Starke.3 However, since this is not familiar chemistry in its nonaqueous setting, it is perhaps well to point out some general metallurgical principles and applications. One can use, as point of departure, the fact that HC1 dissolved in pyridine is an acid very much the same as aqueous HC1. It thus gives essentially all the reactions of the HC1 with which we are familiar. However, when the ratio of HC1:pyridine reaches 1:l (a ratio far higher than is possible with H2O) the solution becomes solid C5F5NHC1, pyridinium chloride.* Inter- estingly, the acidic properties of HC1 persist in this medium, although they are manifest only in the molten state of the compound. Some typical reactions of divalent metal compounds which we have carried out in our laboratories are the following: 2PyHCl + Zn — (ZnCl2) + H2 + 2Py 2PyHCl + MnO — (MnCl2) + H2O + 2Py 2PyHCl + CuS — (CuCl2) + H2S + 2Py 2PyHCl + CaCO3 — (CaCl2) + H2O + CO2 + 2Py In these equations, the parentheses indicate a solvated compound which in water would be predominantly a hydra ted cation but which in molten PyHCl will more likely be a complex chloro-anion of the type MC14-. Some important physical properties of pyridinium chloride (PyHCl) are given in Table I. One sees from the data in Table I that at the temperature of molten pyridinium chloride both water and pyridine will boil away. Thus the system will be kept anhydrous. For this reason the reaction 2NbCl5 + 5H2O— Nb2O5 + 10HC1 has no counterpart in molten PyHCl. Instead, the chloride is made even more stable by the formation of a hexachloro complex: Nb2O5 + 12PyHC1 — 2PyHNbC16 + 5H2O + 10Py One interesting property of these complexes is their thermal instability which for the case of niobium can be illustrated as PyHNbCl6 — PyHCl + NbCl5 With a view to possible use of this chemistry in ore treatment, we have attempted to dissolve Pyrochlore (essentially FeO - Nb2O5) and recover the NbC15 from it.

Jan 1, 1968

By R. S. Busk

TWO groups of binary alloys were prepared. The first group consisted of those elements relatively soluble in magnesium: Li, Al, Zn, Ga, Ag, Cd, In, Sn, Hg, T1, Pb, and Bi. These are predominately Group B elements. The second group consisted of most of the remaining metallic elements, all of which are relatively insoluble in magnesium: As, Au, Ba, Ca, Ce, Cu, Ir, La, Mn, Ni, Pd, Pt, Rh, Sb, Si, Te, Ti, W, and Zr. These are all Group A, transition, or rare earth elements. Alloys of the first group were prepared by melting sublimed magnesium and elements as pure as obtainable in a graphite crucible, using a standard flux1 for protection. The melts were poured into a small graphite mold to produce 3xY4 in. diam slugs. Spectroscopic analyses were made of each slug. In all cases, the total impurity content was less than 0.05 pct. The slugs were then heat treated 5°C below the eutectic temperature until complete solution, as judged metallographically, was obtained. Filings from the center of the slugs were compacted at room temperature into 1/2 in. long x 1/4 in. diam cylinders, sealed in pyrex under 1/2 atm of purified argon, annealed at the heat-treating temperature for 1 hr, and quenched in water. After the X-ray diffraction patterns were made, each compact was analyzed chemically for the solute. It was found that the Mg-Li alloys reacted during filing to reduce the Li in solid solution. For this series of alloys, the slug was cold worked, annealed in purified argon, the surface dissolved in dilute HC1 to a depth of about 0.005 in., and the X-ray exposure made on the fresh surface. This procedure resulted in sharp, continuous lines and in true values for the lattice parameters. The alloys in the second group were prepared in the same way except that about 1 wt pct of each solute was added. Since the solubility limit was exceeded, not all the solute dissolved. These alloys were analyzed spectroscopically only to confirm the presence of the solute. The diffraction patterns were of the back-reflec-tion type using the characteristic copper radiation* and a flat cassette. Both the film and the specimen were rotated. The specimen temperature was maintained at 25" ± 1°C. The films had sharp lines; their diameters were measured directly to 0.01 cm. The parameters were calculated from the line diameters using a modified version of Cohen's extrapolation method.2 his method effectively eliminates systematic errors such as film shrinkage, inaccurate alignment, and non-precise film-to-speci-men distance. The random errors were minimized

Jan 1, 1951

By Robert M. Jimeson

At the recent SME Fall Meeting in Salt Lake City, Robert M. Jimeson, Physical Science Administrator of the U.S. Bureau of Mines, cited the research programs underway in the Bureau's Division of Coal Research, and outlined their current status. These research programs have been selected by the Division because of their relative value and high probability of success in contributing to the conservation of the Nation's coal and to the expanded use of coal in current or new markets. Since about 50% of coal consumption in the United States is in the production of electric power, 20% in production of metallurgical coke, and over 20 % by industry in producing process steam and power, the Bureau has placed much emphasis on research that will maintain coal's leadership in these established areas. This emphasis is reflected in the projects discussed on these pages. Bear in mind that this survey is not all-inclusive. Other projects underway include studies on furnace performance factors, improved burner design, and other critical boiler work which can be used immediately by industry to improve efficiency of current practices in power generation; other investigations are aimed at reducing fireside deposits and corrosion of boiler and super- heater tubes, fly ash utilization, and control of SO, from flue gases (a major step in preventing air pollution). These plus many other projects during the past years have served to focus attention on the fact that the U. S. Bureau of Mines is presently making the largest single contribution to this Nation's coal research effort.

Jan 11, 1963

By A. H. Tousley, C. L. Vickers

The author presents a history of the development of the Port of Long Beach from its beginning in 1905 to the present construction of a new bulk loading facility. In describing this new facility, emphasis is placed on such aspects as rail car and truck handling, gravity yard, rotary car dumping, bottom dumping, car dumping equipment, feeding and conveying, ship-loader-stockpiler, stockpiling and reclaim, dust control, and construction problems. Development of the Port of Long Beach, Calif. (see Fig. I), began in 1905. In that year private Long Beach interests acquired 800 acres of marshland in the Inner Harbor area and initiated a program of channel dredging and land reclamation. Efforts to establish a municipal port began a short time later and culminated in the opening of Pier 1 in 1911. An event of even greater significance to the port future also occurred in 1911. This was the tideland grant enactment by the state legislature that conveyed to the city of Long Beach all of the state's rights in the tidelands located within the city boundaries. The grant stipulated that all revenue produced from the tidelands be used for the development of navigation, commerce, and fisheries. During the next 15 years up to 1926, the port's commercial growth was steady, although relatively slow. During this period, several fundamental steps in the development of a major harbor were accomplished. These included the creation of the Board of Harbor Commissioners in 1917, the dredging of the Inner Harbor and entrance channel to accommodate deep draft vessels, and the correction of a serious silting problem through construction of the Los Angeles River Flood Control Channel. These efforts bore fruit during the ensuing 10 years in the establishment of more than $30,000,000 worth of industrial plants and private marine terminals in the Inner Harbor. Commerce over municipal wharves also increased more rapidly, and it became necessary to start the development of the harbor in a seaward direction. In 1936, oil was discovered in the harbor area, and the first Harbor Dept. well was brought in 2 years later. It soon became evident that the city of Long Beach would receive substantial revenue that, under the terms of the state grant of 1911, must be used in the development of the port. It was further realized that to properly guide and coordinate such development, a long range comprehensive plan was essential. The Board of Harbor Commissions contracted with G. F. Nicholson and J. F. Collins, consulting engineers, for the preparation of such a report that was completed in 1940. The Nicholson-Collins report proposed the development of an East Basin, between the entrance channel and the Los Angeles River, and a West Basin in the area now occupied by the Long Beach Naval Shipyard. Twenty full-size berths were to be provided in the East Basin and more than fifty berths in the West Basin. The report recommended extensive modern terminal facilities for handling waterborne cargo. Attention was given to improvement of the street and highway system to give better vehicular access and to avoid congestion within the port. To a large extent the recommendations of the Nicholson-Collins report were followed in the subsequent development of the East Basin. This development was greatly accelerated by World War 11, with its need for increased oil production and additional shipping facilities. The wartime and immediate postwar construction was largely concentrated on Pier A, with the development of Piers B, C and D following in more recent years. An important factor in the planning of these piers was their dual function as oil drilling sites and cargo piers. The Navy's acquisition of the West Basin area made it necessary to depart from the Nicholson-Collins plan and find other areas for future expansion. At the present time only one Inner Harbor Port-owned area having protected deep water frontage remains undeveloped. This is the property fronting on Channel 2 in the Inner Harbor acquired in December 1957, from Pacific Dock and Terminal Co. The growth of the port has been in a southerly direction since the construction of the Long Beach Naval Shipyard in the West Basin area. Recent extension of Piers F, G and J into the ocean follows typical port construction methods developed during the expansion of the Middle Harbor during the last 20 years.

Jan 1, 1963

By R. T. Hukki, P. Voutilainen

This paper describes a new apparatus for continuous wet fine-screening. Its preferred size range seems to be from 0.1 to 1 mm. The supercritical trommel screen is a short cylindrical trommel of wedge-bar type construction operated at a speed greater than the calculated theoretical critical speed and at a speed lower than the speed at which particles introduced into it will centrifuge. The paper describes results obtained with the prototype supercritical trommel screen in pilot plant scale. The results point to a high capacity and simultaneously to a high sharpness of screening. Finally, an analysis is presented of the forces acting in screening on a supercritical trommel screen. In the era of high speed, high capacity processing of raw materials the conventional slowly rotating trommel screen is often considered a relic from the times passed. A typical trommel screen is the cylindrical trommel rotated about a horizontal or slanting axis at a relatively low speed. Its screening characteristics are well known. Trommel screens of various types of construction, methods of operation, performances and other characteristics have been described in detail by Taggart.1 The theoretical critical speed of a trommel screen is defined by the same well known equation as that applied for grinding mills: where ncritical = the numerical value of the theoretical critical speed in rpm, D 1 = the inside diameter of the trommel in feet, and D2 = the inside diameter of the trommel in meters. ncritical corresponds also to the centrifuging speed provided that the coefficient of friction f between the trommel surface and the outer layer of the charge is = 1.0. In a general case: From Eq. 2 it is seen that in all cases where f < 1.0 the centrifuging speed of the trommel is greater than the theoretical critical speed. The supercritical trommel screen concerns screening operations within that speed range which is between the theoretical critical speed defined by Eq. 1 and the centrifuging speed defined by Eq. 2, under conditions such that the coefficient of friction f<1.0. It is reported by Taggartl that the optimum speed of a conventional cylindrical trommel screen 36 in. in diam was experimentally found to be about 16 rpm. From Eq. 1, the critical speed of this trommel is 44.2 tpm. The indicated optimum speed corresponds to (16/44.2) x 100% = 36.2% of the theoretical critical speed. The optimum speed range based on information available seems to vary from 33% up to 45% of the theoretical critical value. The trommel screen operated at a supercritical speed: operates at a speed greater than the calculated theoretical critical speed; operates at a speed lower than the speed at which the charge introduced into it will centrifuge; operates within the supercritical speed range in such a way that the coarse fraction of the charge must slide in respect to the inside surface of the trommel; the outer layer of the said fraction next to the screen tends to proceed in the same direction as any selected point on the trommel surface, but now at a lower speed, and indeed at a subcritical speed; allows to a certain degree adjustment of the maximum determining particle size x of the fine product simply by a variation of the speed of the trommel within the supercritical speed range. With increasing trommel speed, finer and finer material only will get the opportunity to find its way into the fine product while the screen opening remains constant. In conventional practice, the low speed trommel is generally used for sizing of coarse and medium coarse material, but seldom for fine screening. The characteristic feature of the product passed through the conventional trommel is that the determining size x of the biggest particle is barely smaller than the nominal size of screen opening. The supercritical trommel screen, on the other hand, is best suited for sizing of relatively fine material. Furthermore, the characteristic determining size x of the biggest particle in the fine product can be substantially smaller than the nominal width of the screen opening or slot. In the trommel screen best suited for the applications

Jan 1, 1965

By Frederic H. Wright

The secondary metals industry might well be defined as the group of remelters, smelters, refiners, and manufacturers that convert scrap metals or residues to commercial forms. In this industry, scrap metals and residues are processed to pro- duce refined metals, ingot alloys, fabricated shapes, and chemical products. Secondary metal is defined as metal recovered from commercial scrap, that is, scrap that has entered the processor&apos;s plant in scrap form. Metal recovered by a manufacturer from "home scrap" generated in his own plant is not considered to be secondary, because it represents part of the original stock that simply requires additional treatment before emerging as a finished product. In any economic study, a basic point of measurement must be chosen, and in the case of secondary metals, the melting pot or its counterpart represents the stage in which metal is converted from scrap to some more usable form. Beyond this point there is often no means to distinguish between secondary metal recovered from scrap and virgin metal produced directly from ore. In the last fifteen or twenty years the secondary metals industry has grown to major importance. Some consumers distrust secondary metals, but frequently this distrust serves only to prove an inability to keep up with the times. A rapidly decreasing number of manufacturers like to boast that they use only virgin metals, but a little investigation would show them that more than one third of all

Jan 1, 1943

By Blamey Stevens

(San Francisco Meeting, October, 1911.) My previous paper is entitled, The Laws of Igneous Emanation Pressure. The present paper lays no claim to the exactitude and completeness of a law, since it is of a provisional nature and may be disregarded when experiments have established a basis for more exact reasoning. The general physical states in which aqueous emanations may occur are first considered. The possible physical conditions under which the mineral elements may occur in emanations are then discussed, and a classification of deposits, dependent on emanation, is proposed. A system of scientific experimental investigation is outlined, and it is shown that the physical and chemical properties of emanation may be exactly determined thereby. The investigation is urged as feasible and simple, and not necessarily requiring large and costly apparatus. It is the only step necessary to make possible the formulation of a complete set of laws of igneous emanation. Process of Emanation. In a rising column, magma ranges in temperature from 900° to 1,200°C. Exhalation must begin at some fairly great depth. What this depth may be we can only surmise, since no experimental evidence is available. Exhalation, however, continues as the magma flows upward, until at another level the occluded gases have all escaped. This depth is probably upward of 5,000 ft. (See Fig. 1.) All exhalations must come from between these two levels. As the whole emanation is the sum of the exhalations and residues, the residues must come from below the uppermost level. They will be most abundant when coming, from those parts of the intrusion which have solidified below the lower level.

Apr 1, 1912

By Lord Marley

ACTIVE participation by the United States in the war acted as a stimulant on the Annual Institute Meeting in New York rather than a retardant as feared. Attendance was about 10 per cent under the all-time high reached last year, but considering the number of men who could not possibly come because of active military service and the additional number who are devoting their whole time and effort to turning out vital war materials, the registration was really greater than might have been expected. But all in all the Institute put on a show that taxed the capacity of the Engineering Societies Building as well as the capacity of the visitors to find time to attend everything that promised to be of interest.

Jan 1, 1942

By Grimes, J. A.

EXTENSIVE discovery &apos;and rapid exploitation of orebodies within the past half century have attracted many able geologists to the mining industry and furnished them a wealth of data from which to develop theories concerning ore genesis. By tosting and elimillating theories which are not sufficiently sup- ported by fact, or which are based on inaccurate observation of field data, the trend of geological opinion has . moved strongly in certain directions until, at the present time, large numbers of geologists subscribe to a broad concept of .ore genesis that I would summarize as below:

Jan 1, 1928

By Nathaniel Herz

PARTING of bullion before shipment to the mint had been considered by the Homestake Mining Co. at various times, but had never been attempted before 1933, be- cause the margin of profit appeared to be too small to warrant the complications in refining. When the gold standard was abandoned by the United States in the spring of 1933, however, parting of the bullion was decided upon. The method selected was the Miller or chlorine process, which consists of the passing of gaseous chlorine into a bath of molten bullion, converting all metals other than gold into chlorides, and remov-

Jan 1, 1935

By Chase Palmer, Edson S. Bastin

While the reducing action of organic matter, of ferrous sulphate, and of hydrogen sulphide has frequently been invoked to account for the deposition of native gold and silver from ore-forming solutions, the high efficiency in this respect of certain of the metallic minerals which form the ore itself has not been suffciently recognized. If a little finely powdered chalcocite is placed in a test-tube arid 2 or 3 cc. of a dilute solution of gold chloride are poured over it, two or three shakes of the tube suffice to remove all the gold from the solution. The color of the solution changes from yellow to pale green, showing that copper is dissolved simultaneously with the precipitation of metallic gold. If a piece of chalcocite is hung in a dilute aqueous solution of silver sulphate (1/40 normal), a coating of silver begins immediately to form on the mineral, and within a few moments a beautiful silver tree has developed, similar to that formed when metallic zinc is immersed in a similar solution. When similar experiments are conducted with other sulphides and with certain arsenides and sulph-arsenides, especially those known to be commonly associated with native silver in ore deposits, it is found that these minerals differ greatly in their efficiency as precipitants, especially in their effect on silver solutions. The tests made with most of the minerals were qualitatipe only, but the reactions of a silver sulphate solution on chalcocite and niccolite were submitted to quantitative study to determine the nature of the reactions involved. Quantitative studies of the reactions with other minerals are now in progress

Jan 1, 1914