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By S. Chander, V. N. Sharma

Nickeliferous laterite ore from Sukinda, Orissa (India), consists of very fine particles agglomerated into larger aggregates. The ore is chemically and mineralogically complex and presents many characterization and beneficiation problems. In this study the results of a detailed investigation to characterize the ore by several techniques are discussed. Various techniques used for characterisation include elemental analysis, electron microscopy, electronspectroscopy for chemical analysis, x-ray and electron diffraction, differential thermal and thermogravimetric analyses, EDAX analysis, Mössbauer and infrared spectroscopy. Generally one method compliments the other and it is shown that a combination of several techniques is necessary to fully characterize the ore. The scope and limitations of the techniques are also discussed.

Jan 1, 1980

By G. J. Borbely, E. A. Devuyst, V. A. Ettel

Introduction Of the techniques reported for cyanide removal from effluents, alkaline chlorination is the most common (Fisher and Wasser, 1969; Reidt, 1969). Shortcomings with this technique are the high reagent costs, chlorine contamination, and potential formation of cyanogen chloride. Chemical oxidation methods are also not suitable to remove cyanide from effluents containing sulphides in suspension, such as flotation tailings. An inexpensive method for removing cyanide, combined cyanide and related species from waste waters has been developed in Inco laboratories. The method is based on the use of sulfur dioxide (or a sulfite), lime, and air as the reagents. The decomposition reactions of cyanide, combined cyanide, and related species are catalyzed by copper in solution. Complete removal of cyanide species, most of which are oxidized to cyanate, is obtained by treating copper containing cyanide effluents with sulfur dioxide-air mistures while maintaining the pH between 6 and 10 with addition of lime. The new approach can also be applied to selective destruction of cyanide and combined cyanide in effluents containing sulphides in suspension, such as pyrrhotite. Again, a sufficient amount of dissolved copper must be present or added. Metals and precious metals present in the effluents are recovered as hydroxides by adjusting the pH of the treated effluents to about 9-10. Using the new method, the anionic species are removed in the following order: Free CN- > Complex CN- > Thiocyanate The above removal sequence is unusual as oxidants such as chlorine and ozone oxidize thiocyanate preferentially over the combined cyanide.

Jan 1, 1985

By Leonard Austin

WHAT Colonel Dwight says regarding the treat-ment of oxidized ores1 holds true also of the silver-lead smelting operations in Utah. The ore sought for was such as would, with appropriate fluxes, yield slag, and "lead bullion," as the lead reduced from the ore and carrying its gold and silver, was called. No matte, and probably little or no speiss, was yielded, and hence there was nothing to roast, either of ore or matte. But, by 1880, when I first took hold in smelting, there was quite a production of matte at the works of the Ger-mania Smelting and Refining Co., Utah, because, by that time, ores containing some pyrite and galena were being smelted. This was due, as at the Grant Works, Denver, to the more attractive price paid for the treatment of such ores. The matte, containing about 5 per cent. copper, was accordingly heap-roasted and returned to the blast furnace for the recovery of its contained metals. By this time there had been built a long-bedded, hand-rabbled reverber-atory roaster with a hearth of about 40 by 10 ft. in size, and in this matte and ore, crushed at the sampling mill, was treated. When, in 1892, I took control of this works, called& now the Germania Lead Works, three other roasters had been added, but the prac-tice of heap-roasting continued. This had the merit of needing no equipment, and of doing good work, because the pieces that were imperfectly roasted went back upon the next roast heap. At this time, when some suitable lump ore was obtainable, I roasted in heaps, in a satisfactory way. By 1892, the Bruckner cylinder roaster had been installed, which, compared with the reverberatory roaster, reduced labor. As such a cylinder revolves, a talus of ore is formed within it and at the same time fresh surfaces are exposed to the air, but the trouble was that the air did not reach to the bottom of the cylinder. This we corrected by placing a steam jet at the fire-box end, to project the air down-ward upon this stagnant ore, thus increasing the speed and completeness of roasting without at the same time increasing dust formation. The firing, if skilfully done, gave a somewhat sintered product, but with certain ores a slight access of heat over the normal would cause accretions to form within the cylinder near the fire end. These could be cut off by running back the fire box and barring off the crusts. It was in 1895 that the Bruckner cylinders at the Arkansas Valley plant, Leadville, were giving unsatis-factory service and I was called in to investigate. The steam jet was put in use as at the Germania Lead Works, but we found that, due to the altitude (10,500 ft.), combustion was feebler than at sea level or even at 4000 to 5000 ft. Later it appears, as Colonel Dwight states, that R. D. Rhodes and Mots sought to increase the air supply by admission through perforated tiles, but the trouble was due to the air itself.

Jan 8, 1922

By Michael J. Klishis, Daniel K. Thomas

This paper describes and evaluates factors to be considered in applying computer based instruction (CBI) to the mining industry. CBI is especially suited to the monitoring of training functions and to the delivery of competency-based task training. Its effectiveness is dependent upon: (a) organizational factors (size, number of trainees and trainers, and current training budget), (b) appropriate hardware (accessibility, exclusivity, user-sophistication, transportability, graphics, and cost), and (c) appropriate software (flexibility, response evaluation, video interaction, graphics, and trainee management).

Jan 1, 1983

By John D. Gill

THIS paper assumes the incontrovertible nature of the statement that the validity of competition in the nonnatural resource industries is established firmly on the rate and extent of the economic development of the United States. It then demonstrates the nonexistence of any condition within the petroleum industry that would invalidate the principle of competition as applied to it. It points to the benefits that competition has effected in the oil industry and the reasons why the practice of the competitive principle should continue to keep the industry virile and progressive in meeting the requirements of future generations for the kind of products natural to it. Finally, it pleads for a clearer view of the affairs of the oil industry by seeing them against a background of the whole economy. INTRODUCTION Even a few years ago there would have been only an academic reason for presenting before this Institute a paper on the validity of competition in the oil industry or any other natural resource industry; today there is no more practical subject for this body to consider. In social importance it transcends attempted solutions of perplexing technical problems; and even the numerous legal and economic problems that grow out of administration of state regulatory measures appear to be of secondary importance because they would cease to exist if competition were abolished. The aspiration of certain elements of the Federal Government to acquire control of the oil industry has long been suspected The vital need for petroleum in the national defense ... confirms my belief in the urgent need of Federal legislation to safeguard our petroleum supply through prevention of waste and by establishment and maintenance of sound economic conditions in the oil industry... . But also it may be dismissed with this mere mention of it because it predicates government control and the abandonment or broad reduction of competition on a war emergency. Clearly, the fight for a nation's life may justify a government's control over men and resources that would be abhorrent and economically enervating under conditions of national security. More pertinent to the present matter, because it appears expressive neither of a personal ambition nor of an emergency condition but rather of the long-range view of a certain school of conservationists, is the pronouncement of no less an authority than the Attorney General of the United States, who has been repeatedly quoted by the press as saying that the American Petroleum Industry constituted a case "where the principle of conservation of an exhaustible and irreplaceable resource should replace the principle of competitive exploitation." The significance of this statement in the light of the commonly accepted meanings of the " principle of conservation" and of the "principle of competitive ex-

Jan 1, 1941

By J. C. Karcher

GEOPHYSICAL methods have been more extensively applied to prospecting for oil during 1936 than at any previous time. Their use has been extended to include al- most every oil and gas producing area in the United States. More than ten magnetometer parties, more than nine gravimeter parties, more than five electrical surveying crews, more than fifty torsion balance parties, more than two hundred seismic reflection parties, and several refraction parties were- operating in the United States throughout the year. A tendency has been noted to abandon the use of the pendulum for geophysical prospecting in the oil fields and to increase the use of the

Jan 1, 1937

By R. A. Thomas, R. L. Solbod

The importance of transverse diffusion on the finger development in a miscible-phase displacement at an adverse mobility ratio of tbree was studied in a porous plate 1/4-in. thick, 3-in. wide and 18-in. long. Fast displacement rates (29 ft/D) and slow rates (1.6 ft/D) were used to determine the effect of residence time on the geometry of the fingers. The shape of the fingers was observed directly by use of the X-ray technique. At fast rates numerous narrow fingers were observed, but at slow rates a single somewhat bulging finger was produced. The amount of material moved transversely by diffusion across the plate was sufficient to modify the finger geometry in the slow-rate run because of the long residence time. These results are in contradiction to some of the postulates in the literature. The composition of the effluent stream, however, was not affected by the flow rate. This result is not inconsistent with the observed change in the shape of the finger in a short model, but it seems likely that a short model does not offer adequate and proper scaling of the reservoir. The model used was probably a valid one for studying the effect of transverse diffusion on the finger geometry, but a longer model would be needed for proper scaling of the effect of the change in the finger shape on the efficiency of displacement as measured by the composition of the effluent stream. INTRODUCTION Fingering can be defined as the uneven advance of the injected phase as it moves into a porous medium displacing the resident phase from the pore spaces of the rock. The use of this term is usually restticted to the situation in which the displacing phase is less viscous or more mobile than the fluid being displaced. Under these conditions, not only are fingers formed, but the length and width of the fingers grow with distance traveled in the porous medium. This subject has become one of great interest to the oil industry because of the present trend toward the use of various forms of miscible-phase displacement to increase oil recovery. Since in nearly all of the known modifications of the miscible-phase displacements an unfavorable mobility ratio exists (the displacing phase has a lower viscosity than that of the crude oil), the conditions are proper for fingering to develop. An appreciable amount of fingering appears to be a severe handicap to these processes for it increases the volume of agent required for the process to be a success, and such an increase puts a severe strain on the economics of the proposed processes. In some cases, such as for a mobility ratio of 200 unfavorable, it has already been demonstrated that the proposed process would not be economic if the fingering in the field were to be of the same magnitude as that observed in the laboratory. A number of aspects of fingering have been studied and reported in the literature. While the phenomenon of fingering cannot be regarded as a completely understood subject, considerable information exists on the effect of the path length and the mobility ratio on the growth of fingers. Less-complete data are available on the effect of the diameter of the flow path on the character and amount of the fingering, and even less agreement in results exists on the effect of rate of flow on the nature of fingering. This paper deals with one aspect of this latter subject. OBJECTIVE The objective of this study was narrowed down to one rather specific feature of the behavior of fingers in miscible-phase displacement in porous media. The variable studied was the effect of rate of flow on the nature and the development of fingers. It should be made clear at this point that, while rate was the apparent variable, the real variable was residence time; that is, at low rates the fluids are present at a given spot in the porous medium for a longer time interval than at fast rates. The purpose of the study, therefore, was to determine the changes which occur in the fingering and the possible benefits which might accrue from a longer residence time during that period when fingers are

By A. J. Shaler, B. F. Oliver

Jan 1, 1961

By D. S. Choi, D. L. McCain

A method of estimating the chain pillar size required to support the wide working faces of longwall or shortwall coal mining is presented. The pillar size is determined through the use of coal strength, entry geometry, panel width, and overburden pressure. Design analysis is focused on a three-entry development system in the Pittsburgh Seam but can be used for other development plans and other seams by substitution of the proper geometric and strength data.

Jan 1, 1981

By S. P. Brown, J. E. Worthington

Increasingly, exploration geology seems to be growing into a practice overly separated from production geology, yet the eventual purpose of exploration is a producing mine. To help in the search for new deposits, exploration "lessons" will be drawn from the papers given at the Fall AIME Applied Geology Symposium. In addition, examples will be re-emphasized to show how early observation of matters now routine to mine work (for example, hydrology, rock mechanics, oxidation state) can help increase the effectiveness of exploration.

Jan 1, 1984

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Jan 1, 1938

Jan 1, 1932

HAVING told you about steel in the previous chapter, it seems to me necessary to speak here of brass for the same reason, for it bears the same relation to copper that steel does to iron. It is the opinion of some concerning both of these that they are true minerals because Pliny in his Natural History calls it aurichalcum and says that it has its own ore; he does not say, however, where it is found, and I have not heard from anyone else that it has been found anywhere, and, surely, if it had been found when he wrote, it would also be found today. Since I have no knowledge other than that gained through my own eyes, I tell you as a certainty that just as steel is iron converted by art into almost another kind of metal, so also brass is copper given a yellow color by art. Surely it was a splendid discovery, for which we must praise the alchemists,* although perhaps whoever discovered it was deceived, thinking that he had made gold from copper. Now, in short, this work requires infinite labor, and is carried out in various places, for instance, in Flanders, Cologne, Paris, and in many other countries, and also in the city of Milan in Italy, where I have seen a

Jan 1, 1942

By L. D. Godshall

The latest revised edition of Mr. C. A. stetefeldt's book on the Lixiviation of Silver-Ores, which appeared very recently, contains no mention of the volatilization of silver in chloridizing-roasting—an omission which is the more remarkable in view of the fact that in former editions of the work this important subject was noticed. Moreover, Mr. Stetefeldt has discussed it to some extent in his paper on " The Stetefeldt Furnace," * in which he criticised certain statements made by me before the Colorado Scientific Society in May, 1893, in a paper entitled " A Review of the Russell Process;" ? and Mr. Morse, in his paper on " The Lixiviation of Silver-Ores by the Russell Process at Aspen, Colorado," $ has given statistics showing the loss of silver by volatilization (including the dustloss, which Mr. Morse estimates at not more than 1 per cent.) on more than 30,000 tons of ore roasted, to have been 9.16 per cent. The matter must certainly be deemed important enough to warrant me in returning to it, and offering, with the aid of the figures made public since my first paper, a reply to the criticisms of Mr. Stetefeldt. The passages of my paper which he deemed to be " ques-

Jan 1, 1897

By Lester C. Uren

THIS paper reviews the industrial trends and changes in educational concepts that have led to the development of the modern petroleum engineering curriculum. A trend toward emphasis on engineering fundamentals is noted. While most universities are committed to the traditional four-year engineering program, it is agreed that more than four years is necessary for academic preparation of the petroleum engineer in all phases of his profession. The author proposes a coordinated program of undergraduate and graduate training that will permit of adherence to the general pattern of the present four-year engineering course, with provision for extension of the program into specialized graduate courses of professional character. In the latter, emphasis may vary with the interests and objectives of the individual student. A specific undergraduate curriculum is proposed in which upward of 80 per cent of the available time is devoted to engineering fundamentals. A broad survey of the professional field is afforded in courses grouped in the third and fourth undergraduate years, but detailed treatment of the professional aspects of petroleum engineering is reserved for the graduate program. INTRODUCTION Of necessity, engineering curricula must ever be changing to reflect the new techniques, the changing concepts that are presented as the engineering industries develop and unfold. Particularly is this true of the younger engineering curricula representing comparatively new and rapidly changing industries such as the petroleum industry. Institutions that planned their petroleum engineering curricula a decade or two ago now find that the petroleum industry has become vastly more technical in its requirements. Entirely new methods and techniques have come into vogue and must be given place in the curriculum, and some of these are of a character that demands changing emphasis in the fundamental preparatory subjects. College and university faculties cannot complacently assume that curricula in this field that were considered appropriate 10 or 20 years ago still reflect the needs of the industry that they are designed to serve. If they do, their graduates will be poorly equipped to meet the requirements imposed upon them by a rapidly changing industry. Perhaps it is not too much to expect academic authorities to anticipate the trends of industry and equip their graduates with what they will need to attain leadership 10 or 20 years after graduation. Whether or not this desirable objective is possible, there is no excuse for allowing curricula to fall behind the current needs of industry. DURATION OF CURRICULUM The majority of our engineering schools and colleges still adhere to the four-year curricula and there appears to be a definite - sentiment among many engineers engaged in industry that work should be so planned that the engineering student may secure the essential academic preparation for his profession in a terminal four-year program. Yet, in recent years, it has become increasingly apparent that four years of

Jan 1, 1941

By D. E. Munson, P. R. Dawson

An empirical model is developed that predicts accurately the transient response of salt creep to incremental and decremental changes in stress and temperature. Even though the model is empirical, it is derived from a firm theoretical framework for the micromechanical deformation processes of both steady-state and transient creep. In the model, the transient creep functions modify the steady-state creep behavior, which in turn is based upon creep mechanisms and the def ormation-mechanism map. The model is applied successfully to experimental stress-drop results obtained for salt.

Jan 1, 1982

By GEORGE H. DERN

IF THE engineer is to go into politics, as I think he should, I believe the curriculum of every engineering school should be amended to include a good stiff course in public speaking. My observation has been that the engineer in private conversation can scintillate as brightly as a life insurance agent or an oil stock salesman, but before an audience, with rare exceptions, he is a total loss. He will not get up and talk. He hides his light under a bushel, and sits on the bushel as dumb as an oyster. I have seen meetings of the Utah Section at which some topic of general interest to the members was up for discussion, and where an animated debate was the logical thing to expect. After the chairman states the subject and invites discussion, there is dense silence. Finally a member, bolder than the rest, gets up and with trembling voice and knees makes a motion. The motion carries, the meeting adjourns, and then the members gather into groups and begin to discuss the question seriously -and intelligently, giving cogent arguments on either side and embellishing their remarks with appropriate or inappropriate epithets illustrations and figures of speech. Now, I am not pleading for more speechmaking. The good Lord knows we have too much of this great American indoor sport already. But I think every man ought to be able and ready to express his opinions at the proper time. Some men have a reputation for wisdom because they do not talk much. We speak of the wise old owl because she never speaks, but in my opinion the owl's reputation for wisdom is vastly overrated. silence is more apt to be a cloak for stupidity than for wisdom. The person who has ideas can- not exert any influence by keeping them locked up in his own mind. The great motive force of the world is not muscle, but ideas, and ideas in order to get in their work must be released.

Jan 1, 1925

Jan 1, 1951

By Morgan Walker, C. D. Watson, Reid W. Bond, D. L. Trax

Common practice in the Mid-Continent until recently was to prolong the natural flow of oil wells as long as possible by agitation, and then swab for a short period until the well was put on the pump. Comparatively recently the gas-lift has superseded the swabbing and agitating period and in some cases encroached on the natural flowing life, particularly where it was evident that the potential oil capacity of the well was greater than the gas supply, or lifting medium. The majority of wells are finished with either 6¼, 65/8 or 8¼-in. casing and connected to a separator through a flow line which is usually 65/8 in. The flow line is generally designed to eliminate sharp turns and has reduced the gas-oil ratio and therefore increased the efficiency in a good many instances. Until recently all wells were allowed to flow without restriction against the possible trap pressure until it was deemed advisable to put them on gas-lift. This resulted in a fairly efficient flow during the early life of the well if the well was rather large but was usually inefficient in small wells and in the later flowing life of large wells, on account of the large area in the casing and therefore excessive slippage. Recently, considerable effort has been made to increase the efficiency of small flowing wells by running tubing to eliminate as much slippage as possible. With large wells there is a considerable trend toward back-pressuring, or beaning to find out whether it is possible to reduce the gas-oil ratios and increase the flowing life. The greater number of fields that have been back-pressured have been produced in that manner through necessity, either to restrict production for proration purposes or, in fields producing by hydraulic pressure, to reduce water encroaching. The recent Cromwell sand development in Little River is an example where both back-pressuring by means of high-pressure traps and beans and flowing through tubing were used to conserve gas, reduce the high gas-oil ratio and prolong the flowing life. It

Jan 1, 1930