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By H. H. Kellogg

An invitation to address you on the occasion of the one-hundredth anniversary of AIME represents an honor, a challenge and an opportunity: an honor that you judge me worthy; a challenge that I present to you a picture of extractive metallurgy in the years ahead that contains some ideas of value; and finally, an opportunity for me to express some deeply felt beliefs about our profession and our industry. My topic concerns the technology of metal production in the future - the processes, new and old, that will be used to extract metals. The nature of these processes will be shaped by many forces - some technical, some economic, some political or social. A forecast of future technology must recognize the role of each of these forces, and I have endeavored to do this in the analysis that follows. In brief, my outline consists of an analysis of the forces (perhaps better called "problems") that will influence the future of our industry, followed by consideration of likely lines of technological development to meet them. Let me dwell for a moment on the nature of this industry and the profession that serves it. I have been engaged in the profession of extractive metallurgy - teaching, researching and consulting - for 30 years. I have always found the subject stimulating and rife with challenges of a scientific, engineering, economic and socio-political nature. It is a big subject - it encompasses most of the elements of periodic table; we measure the U. S. production of six metals in millions of tons per year; new plant costs range to $100 million and more. The supply of metals from our extractive plants plays an essential role in our modern industrial economy. We could do without DDT, or phosphate detergents or 300-page Sunday newspapers; we cannot do without a huge and increasing supply of metals. The Basic Goal of Extractive Metallurgy Understanding of some basic forces that shape this industry can be gained by consideration of the question: What determines the utility of metals to man? We think immediately of the inherent properties of metals - strength, ductility, electrical conductivity and so forth - but these tell only part of the story. Metal price and the available supply play equally

Jan 1, 1971

In the period considered all coal produced was used locally, and the totals in Table 43 are estimated from the few data available. [ ]

Jan 1, 1942

By M. R. Tek, F. H. Poettmann, M. L. Grove

The general problem of single-phase natural gas flow through porous media has been considered both by mathematical analysis and field experiments. Theoretical studies on the fluid dynamics of natural gas wells resulted in derivations of expressions which permit a ber-ter understanding of the flow mechanism for conditions under which Darcy's law is no longer valid. In applying these results to natural gas production and testing technology, special emphasis war placed on the study of low permeability, slowly stabilizing formations. These applications resulted in a method of predicting the performance coefficients of tight natural gas wells. The calculation of the performance coefficient requires the determination of the "test-index", pkh/µ, the drain- age radius, R, and the effective wellbore radius, rw. Methods for estimating these parameters from field data were also developed. Field data from 15 wells were collected and analyzed. The measured values of the performance coefficients were compared with the predicted values. This statistical evaluation gave a bias of 7.14 per cent and a standard deviation of 11.6 per cent. INTRODUCTION The performance of a natural gas well is determined by the physical properties of the reservoir rock, the extent and the geometry of the drainage area, the properties of the flowing fluid, and the conditions of pressure distribution within the drainage matrix. The relation between the quantity of gas delivered and the pressure drop within the reservoir is characteristic of the behavior of each well and is often referred to as the back-pressure behavior of the well. It is well established that for normal, single-phase gas wells the relationship between the gas delivery rates and the bottom-hole pressure take, in general, the form, Q = c(P3 8 -P2 1)n. ,.......(1) where C is the performance coefficient, and n is the exponent corresponding to the slope of the straight-line relationship between Q and (P2 s, — P2 l) plotted on logarithmic coordinates. The determination of a well's performance by the back-pressure behavior not only permits the production engineers to analyze many operating problems, but also provides necessary information useful and essential to predict the future development of the field.' Important engineering and production problems such as calculation of gas deliverability into a pipeline at a predetermined line pressure, design and analysis of gas-gathering lines, determinations of spacing and number of wells to be drilled during field development to meet future market or contract obligations, etc., all depend, at least in part, on the availability and use of reliable back-pressure curves.' In the past the behavior of gas wells was evaluated

Jan 1, 1958

By R. G. Robins

The processing of gold bearing sulphide minerals which contain arsenopyrite and various complex arsenic sulphides results in arsenic containing emissions and effluents which are suspect in relation to clean air and clean water standards. Removal of arsenic from gaseous emissions is briefly reviewed. The use of lime to stabilise aqueous residues as either calcium arsenate or calcium arsenite is shown to be inadequate for long term disposal since both compounds are converted into calcium carbonate due to the influence of carbon dioxide in the atmosphere. Mixed calcium arsenate-phosphate residues are similarly unstable, but present better stability than the straight calcium compounds. Alternative disposal methods are reviewed whereby the arsenic is converted to more stable compounds, such as barium arsenate, titanium (IV) arsenate, and arsenic sulphide.

Jan 1, 1984

Jan 1, 1899

By Frederick Sharpless

THE term "segregation," as here used, means the separation of certain natural resources into groups, consisting of one or more members, with the idea that when thus segregated, each group may be more easily and effectively administrated. We may, for example, consider surface rights as distinct from underground rights, and stop there; or we may go further, and deal separately with timber, water, and agricultural rights, or, going underground, we might deal separately with such groups as precious and base metals, clay, oil, gas, etc. The present paper contemplates only the separation so far as practicable, for administrative purposes, of surface from mineral rights. "Classification," in this paper, has reference to the groups into which the government has divided, is dividing, or will hereafter divide its natural resources; first, into the broad classes of mineral and agricultural lands; and, second, into coal, oil, phosphate, brine lands, etc., the central idea being the separation into natural groups for the purpose of simplifying administration and for the purpose of encouraging maximum development and minimum waste. The two subjects are in some respects quite distinct, but as my argument develops, I think it will be obvious why they are discussed in the same paper.

Jan 4, 1914

By L. E. Mannion

Sodium carbonate (soda ash) is one of two principal commercial alkalis. Its principal competitor is sodium hydroxide. The use of sodium carbonate is recorded in ancient Egypt, where naturally occurring brines and solid salts provided impure soda for early glassmaking. Until the 19th century, soda ash (as well as potash) was recovered mainly by leaching wood or other plant ashes. In 18th-century Europe, for example, leaching seaweed ash with hot water produced a brown laundry lye. One of the better grades of this material was a Spanish product, barilla, which analyzed 24 to 30% Na2CO3 (Hou, 1942). The modern chemical industry was born in 1691 with the LeBlanc process for making sodium carbonate from salt, sulfuric acid, and lime. English industry used this process extensively in the 17th and 18th centuries. The next major advance was in 1863, when Ernst Solvay devised the ammonia-soda, or Solvay process. The first of many Solvay plants was built in 1874. These supplanted the LeBlanc method and dominated worldwide soda ash production until 1974, when mined sodium carbonate became predominant. Although considerably less important until recently, natural sodium carbonate deposits historically have supported small soda ash operations throughout the world. Shortages during World War II stimulated production of "natural" soda ash from such deposits, particularly at Searles Lake, CA and Lake Magadi, Kenya. More spectacularly, increased production from the vast trona deposits in Wyoming has virtually supplanted the Solvay process in the US. Principal producers of natural soda ash as well as the character of the source deposits are listed in Table 1. [ ]

Jan 1, 1983

By E. A. Barnard

ARSENIC is a very old substance. The ancients speak of it in their writings, and its use has developed very little until recent years. The ancients used it in making pigments, in medicine, and for poison. They also tell of the difficulties of handling it-an experience which is very similar to our own. Until about 10 years ago, arsenic was very cheap and was a drug on the market. About that time the boll weevil began making serious inroads on the American cotton crops, and after much investigation the Depart-ment of Agriculture developed a very successful poison for this pest, consisting of calcium arsenate. The weevil pest has continued, and as the cotton planters have become convinced that calcium arsenate is the best material to use against the weevil, the demands for it have been steadily increasing, resulting not only in a rising price of arsenic but in a very serious shortage so far as our country is concerned. So serious has this shortage become, and so vital is it to the cotton growing industry, that Congress has appointed a committee to investigate and report on the situation. A meeting of arsenic producers and consumers was held in New York last December to take stock of the situation and to see what could be done. The extreme increase in, the market price of arsenic-from 6 c. to 15 c. per lb. in less than a year-has been very harmful to the producers as well as to the consumers. Some very interesting' data were brought out at this meeting, as follows: CONSUMPTION PER YEAR, SHORT TONS Arsenate of lead 2,000 Paris green 1,200 Proprietary mixtures 750 Sheep dips : 1,000 Weed killers 1,500 Glass : 2,000 8,450 1922 Consumption as calcium arsenate 4,000 12,450 1923 Estimated consumption as calcium arsenate... 12,000 Estimated 1923 consumption 20,450

Jan 8, 1923

By R. Taggart, G. R. Purdy

DURING a study of the tempering of ß-quenched alloys of cobalt in titanium, parallel lines were observed crossing certain faces of retained-ß crystals in the early stages of tempering, Fig. 1. The lines closely resemble stress-induced martensite' or substructures attributed to clusters of faults in titanium-nickel2 and copper-silicon3 alloys. The markings were observed only in intensely etched quenched and tempered alloys having compositions ranging from 4.5 pct* Co (the composi- formed by the lines was reproduced upon repolishing and reetching. Close metallographic examination indicated that the markings were troughs, Fig. 2, and that the characteristic surface substructure persisted within the troughs. The occurrence of the troughs was associated with the age hardening reaction due to the metastable u) phase (previously reported in titanium-cobalt alloys by Raub and Beeskow4 and indicated in this work by the broadening of 0 diffraction peaks and by hardnesses approaching 600 Dph). The troughs

Jan 1, 1961

By Leslie F. Tedsen, Alan E. Flanigan, John E. Dorn

It is necessary occasionally to use aluminum-alloy sheet where moderately elevated temperatures are encountered. Considerable attention has been directed toward determining the influence of "artificial aging" on the room-temperature properties of the precipitation-hardenable alloys, as testified by numerous company reports and by references I to 4. Investigations on the properties at elevated temperatures are few, however, and have not always covered the range of times and temperatures of greatest interest. The present investigation was instituted to overcome this deficiency. The work was done for the Office of Production Research and Development of the War Production Board, under the supervision of the War Metallurgy Committee, as a part of the "restricted" Project NRC-548. It has been released for publication by the Office of Production Research and Development. AS is well known, the high-strength aluminum alloys achieve their remarkable properties as a result of precipitation-hardening. In production they are subjected to a solution heat-treatment followed by quenching, to retain the supersaturated solid solution. The solution treatment is followed by "aging" (precipitation-hard- ening) either at room temperature or at a suitable elevated temperature. A considerable increase in tensile and compressive yield stresses results from precipitation at room temperature ("natural aging"). Through the elevated-temperature process ("artificial aging") it is possible to obtain values of yield stress considerably higher than those attainable by natural aging. The increase in yield stress is accompanied by a smaller gain in ultimate tensile stress and by a decrease in elongation. During the first stages of artificial aging the yield stress increases steadily until it reaches a maximum value. In this condition the material is said to be "fully aged." Further exposure results in "averaging," attended by a steady decrease in yield stress. In the production of the artificially aged materials, temperatures and times are selected to achieve full aging. The following important characteristics are associated with the process: 1. The higher the temperature, the more rapidly is the fully aged condition attained. :7

Jan 1, 1946

By C. R. Hocott

THE distribution and movement of fluids in oil reservoirs are influ-enced to a great extent by capillary forces, which depend upon the size and shape of the pores in the reservoir rock, the surface characteristics of the rock, and the interfacial tension between the fluid phases. This paper presents the results of an investigation of the interfacial tension between salt water and crude oil containing dissolved gas under reser-voir conditions. APPARATUS AND PROCEDURE In the preliminary phases of this investigation, it was found that a scum formed at the oil-water interface, which made measurement of interfacial tension by either the ring or capillary rise methods unreliable. Accordingly, the drop-weight method, in which a fresh interface is con-tinuously formed, was selected. In this method, a tip through which drops of one fluid can be expelled is immersed in a second fluid. At the instant that the drop becomes large enough to fall, the gravitational force tending to pull away the drop exactly balances the interfacial force tending to hold it. From the size of the drop, the dimensions of the tip, and the density of the two fluid phases, the interfacial tension may be calculated. The apparatus consists of a circulating pump for bringing the oil to equilibrium with gas at the desired pressure, a displacement pump for forming the drops, an interfacial tension cell in which the drops are formed, and a density cell to determine the density of the oil. The density of the water is determined separately in another apparatus. A flow diagram of the assembled equipment is shown in Fig. 1.

Jan 1, 1938

By Harrison R. Cooper

Safety considerations apply from two perspectives in conducting shaft inspections for production and service hoists. The first is to conduct the task more effectively while minimizing the possibility that shaft deterioration may go undetected. The second is to increase security and efficiency of the inspection team in fulfilling its duties.

Jan 11, 1979

Jan 1, 1929

By Kenneth Robertson

ALL, strangers visiting this district are struck with the peculiar manner in which the pig-iron is graded. There are eleven regular grades, besides which, when gray forge is ordered, one-half of Nos. 1 and 2 Mill are shipped. Occasionally there is another grade Known as Silver Mill, which is made so seldom that I cannot describe it, and have no sample to exhibit. Most of you have found it difficult to grade properly and uniformly under the simpler system which obtains elsewhere, and can consequently readily imagine the increased difficulty with us. Each furnace employs an " expert," and even with this precaution, the system is not conducive, at all times, to amicable relations between buyers and sellers. I am told that it was adopted at the time Southern irons were seeking a market; but it still remains, although the time has come when our iron is sought for and has obtained for itself a place in the markets of the country. The grades are as follows:

Jan 1, 1889

By Thomas Wilson

IN a single-crystal cube of iron the arrangement of the atoms is that characteristic of iron at room temperature: the body-centered cubic lattice. X-ray investigation has shown this structure to be characteristic of iron, as it has shown the atomic arrangement of other metals to be characteristic of those metals also. Rarely do substances have more than one characteristic atomic arrangement. Many physical properties of metals are directly connected with their atomic arrangements, so that changes of arrangements produce changes of properties. Only chemical change influences atomic arrangement. If a difference in the physical properties of a metal is caused by a process which involves no chemical change, the cause of the difference in properties must be sought elsewhere than in the atomic arrangement. Frequently this cause can be traced to alteration of crystal orientation. The orientation of a crystal may be defined as the relationship which the crystallographic axes bear to some quantity of reference. A cube of iron appears cubic whether it is regarded from a face, an edge, or a corner. Yet these three positions represent three different orientations of the cube with respect to the observer. It is evident that the orientation of this cube of iron, unlike the atomic arrangement, is not characteristic of iron but is entirely dependent on the previous history of the cube. Most of the processes of metal working, such as wire-drawing, rolling, and bending, change the orientation of the crystals present in the worked metals. These processes usually tend to produce rotation of the crystals into positions approaching a mean. Specimens of metals show-ing this characteristic are said to possess a preferred, orientation. Tensile strength, ductility, and many other properties are influenced by orientation changes; therefore two specimens of the same metal may show different values of these quantities. In metal specimens possessing a narrowly limited preferred orientation, these quantities will vary in magnitude in different directions throughout the specimens. The investigation of the influence of manufacturing operations upon crystal orientation, and hence upon physical properties of metals, is an important

Jan 1, 1929

By Bernard Kopelman

THE particle size of tungsten metal powder used to make tungsten wire for use in radio tubes and incandescent lamps must be closely controlled if the highly desirable feature of nonsagging is to be achieved. Our knowledge of factors affecting the particle size of tungsten powder has been limited by lack of any extensive literature on the subject. There are no publications in the English language discussing this problem in any but the most general terms. In this paper the published experimental information on this subject is reviewed. Based on the published data and some experimental data obtained by the author, a general theory of factors affecting the particle size of tungsten metal powder obtained by reduction of the oxides in hydrogen is offered. The various forms of the tungsten oxides and tungsten metal used in the experiments described were those prepared by com¬mercial processes, so that the experimental results obtained on a laboratory scale would be more directly applicable to actual commercial reduction conditions. The effects of time of reduction, temperature, and concentration of water vapor in the hydrogen were observed by counting microscopically the particle distribution obtained. Such a method is very time-consuming, but the data obtained by this method are more reliable and more fundamental than those obtained by any of the several instruments available for measurement of particle size. REVIEW OF THE LITERATURE Until the year 1912, tungsten powder was prepared commercially by reducing tungstic oxide in the presence of carbon or one of its compounds (such as glycerin or ethylene glycol), usually by firing the mixture in a closed fire-clay crucible. The resultant powder contained about 95 per cent tungsten.1 When reduction of tungsten oxides by H2 was introduced commercially, 2.1 several investigators became concerned with the equilibria between tungsten metal and its several oxides in an atmosphere of hydrogen and water vapor.4-13 While these many investigations were in fair agreement on the equilibria there arose considerable controversy as to the chemical composition of the oxide between W03 and W02, because of very poor agreement on the equilibrium constant of this intermediate oxide reduction reaction. The controversy on this intermediate oxide has been in progress for more than 10o years. Thus Malguti,14 in 1835, decided it was W02.56. In 1857, Riche" proposed the formula W308. Usler,16 in 1865, confirmed the existence of W308 and further proposed W4O11. In 1897, Desi17 agreed upon W308 but also found W5014.

Jan 1, 1946

By S. G., Lasky

IT seems to be in the nature of concepts that they have many meanings, and that the meaning best reflecting the primary interests of a person tends to be accepted by him as the normal meaning of the concept. The concept of ore reserves is no exception, for there is no unanimity of meaning among the several groups of us who are interested in ore reserves, nor even among the individuals of a single group. The groups most interested in ore reserves would seem to include at least the mining industry, perhaps State taxing agencies, and the Federal Government in all its diversified activities, and I would include also the citizenry at large or at least that part of it that consciously thinks about problems-of national welfare. To each of these, and to different individuals within them, the term reserves represents something different, and the farther away the individual or group gets from physical contact with the ore, the more abstract does his or its concept become. It is something different to the policy maker from what it is to the fact-finder or to the miner.

Jan 1, 1945

By T. Y. Yan

SUMMARY Laboratory high pressure column tests have shown that the presence of 1-20 ppm of aluminum ion effectively prevents permeability loss during uranium leaching with leachates containing sodium carbonate. If added after permeability loss has occurred, aluminum ion can restore the permeability to nearly its original value. No deleterious effect was observed on uranium leaching performance and the technique should be quite compatible with all field operations. INTRODUCTION The recovery of uranium values from underground deposits by in situ leaching or solution mining has become economically viable and competitive with conventional open pit or underground mining/milling systems (Merrit, 1971). In situ leaching processes are particularly suitable for small, low-grade deposits located in deep formations and dispersed in many thin layers. Many such ore bodies occur along a broad band of the Gulf Coastal Plain (Eargle et. al., 1971). The advantages of the in situ leaching processes have been reviewed (Anderson and Ritchi, 1968). In the in situ leaching process, a lixiviant containing the leaching chemicals is injected into the subterranean deposit and solubilizes uranium as it traverses the ore body. The pregnant lixiviant or leachate is produced from the production well and is then treated to recover the uranium. The resulting barren solution is made up with the leaching chemical to form lixiviant for re-injection. Upon completion of the leaching operation, the formation is contaminated with leaching chemicals and other species made soluble in the leaching operation and has to be treated to reduce the concentration of these contaminants in the ground water to levels acceptable to the regulatory agencies (Witlington and Taylor, 1978). Restoration is accomplished by injecting a restoration fluid, which could be the fresh water or water containing chemicals, into the formation. As it traverses the leached formation, the restoration fluid picks up the contaminants and is then produced at the production well. This produced water is either disposed or purified for recycle. In both phases of operation, formation permeability or well injectivity is one of the most important parameters which determines the viability of the in situ leaching process. Low formation permeability limits production rates, leading to uneconomical operations. The formation is said to be sensitive if there is a sharp loss of permeability on contact with water and other fluids. Many uranium bearing formations, for example, the Catahoula formation of the Texas Coastal Plain, contain significant amounts of clay minerals which are water sensitive. Serious permeability losses can occur when the pH and chemical composition of the lixiviant is significantly different from that of the formation water. Jones has investigated the influence of chemical composition of water on clay blocking of permeability (Jones, 1964) and Mungan studied permeability reduction through changes in pH and salinity of the water (Mungan, 1965). Various mechanisms of permeability damage have been proposed and reviewed (Jones, 1964; Mungan, 1965; Gray and Rex, 1966; and Veley, 1969). When large amounts of swelling clays are present, a significant fraction of the flow channels in the formation can be reduced due to swelling. However, in most cases, swelling need not be the main cause of permeability losses. Particle dispersion and migration or clay sliming can be more important causes for formation damage. Clay particles entrained in the moving fluids are carried downstream until they lodge in pore constrictions. As a result, microscopic filter cakes are formed by these obstructions, plugging the pores, effectively restricting fluid flow and reducing the formation permeability. Moore found that as little as 1-4 percent clays present in a fine grained sandstone could completely plug the formation if they are contacted by incompatible injected fluids (Moore, 1960). It has been found that injection of NaHC03/Na2CO3 lixiviant into formations with significant clay content often leads to loss of formation permeability and well injectivity. To alleviate this problem a change of the lixiviant composition to KHC03/K2CO3 has been proposed. At present, however, many in situ leaching operations employ NH4HC03/(NH4)2C03 mixtures as a source of carbonates. This approach has been successfully used in South Texas by Mobil, Intercontinental Energy, Wyoming Minerals and U.S. Steel, etc. The use of ammonium carbonates solutions, however, contaminates the formation and requires a time-consuming restoration operation. The other approach to reduce the permeability loss is to pretreat the sensitive formation with chemicals which prevent clay dispersion and migration. Such chemicals include hydroxy-aluminum (Reed, 1972 and Coppel et. al., 1973), hydrolyzable zirconium salts (Peters and Stout, 1977), hydrolyzable metal ions in general (Veley, 1969) and polyelectrolyte polymers (Anonymous). Still another approach, is to minimize the "shock" caused by sudden injection by gradually changing the chemical composition of the injected fluids from that of the formation water. THE APPROACH Since permeability loss can be an important factor limiting the efficiency and economic viability of the in situ leaching process, a study was initiated on

Jan 1, 1982

By E. C. Burke

IN view of rather widespread use of calcium as an alloying addition to magnesium alloys, it is rather surprising to find that, although the general features of the Mg-Ca equilibrium diagram are known with a fair degree of certainty,' ," considerable ambiguity concerning the solid solubility of calcium in magnesium exists. By using the disappearing phase technique in a metallographic study, Haughton' found that 0.6 pct Ca was soluble at 300°C and 1.8 pct was soluble at 516°C, the eutectic temperature

Jan 1, 1956

New Products Equipment

Jan 9, 1950