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By G. M. Swinkels, A. Vizsolyi, E. Peters

A process is described utilizing ferric chloride leaching followed by reduction of the cupric content to cuprous by cement copper, with CuCl obtained thereafter by crystallization. The residual liquor is cemented with sponge iron to produce cement copper and a copper free ferrous chloride solution. The latter is oxidized in an autoclave with oxygen to regenerate ferric chloride and to precipitate excess iron as a granular, filterable hematite. Cuprous chloride crystals are reduced to high purity metal with hydrogen, while sulphur reports almost quantitatively in residues in the elemental form. Pyrite and molybdenite are not leached. This paper describes the important variables in the process, as well as the deportment of minor elements as silver, gold, selenium, tellurium, bismuth, nickel, lead, zinc, magnesium, etc. An elegant method of isolating silver from CuCl crystals is described, as well as recovery of gold from residues by a chloride reagent The process is described as non-polluting and capable of producing refined copper, ore grade iron oxide, elemental sulphur, and yields of minor metals as good or better than obtainable by conventional smelting, without the use of solvent extraction or electrochemistry.

Jan 1, 1981

By James Lee Hibbard, Doraiswami Ramkrishna

A population balance model accounting for the transient variations in drop size distributions in a stirred liquid-liquid system is analyzed for its effect on chemical reaction conversion in a stirred, batch reactor. The analysis is applied specifically for phase transfer catalytic reactions, which indicates that transient effects of evolution of drop size distributions may be important in such systems.

Jan 1, 1981

Joseph HartshoRnE, Pottstown, Pa.: I have read Professor Akerman's valuable paper with great interest. Few of the present generation of American steel metallurgists are aware of the very important part taken by Swedish engineers in the successful development of the Bessemer proeess, and I am afraid some of the older ones have forgotten it. Certainly, I think, most of us would have said that Terre Noire was the first to introduce the use of metal direct from the blast-furnace. It is very well, therefore, that honor should be given to whom honor is due. I can speak from personal experience upon one part only of Prof. Akerman's paper; namely, the effect of the temperature at which the molten metal is cast upon the quality of the finished steel. In a general way I have, of course, known for a long time that the

Jan 1, 1894

TO THE BOARD OF DIRECTORS AND THE MEMBERS OF THE AMERICAN INSTITUTE OF MINING AND METALLURGICAL ENGINEERS Gentlemen -It is pleasant to be able to report that the year just closed has been a prosperous and successful one for the Institute As is shown by the reports of the Treasurer and the Finance Committee, the business affairs of this organization are in excellent condition With property valued at more than three-quarters of a million dollars, and with con¬siderable sums in various funds and endowments, it is possible to spend on each member of whatever class $22 65 each year, more than the maxi¬mum amount of dues received from any one, and substantially twice the average amount, $10.94, received from all To do this has required close management and a strict regard for our limitations In 1926, when the Budget was made up, the estimated expenditures for the work which it was felt the Institute must do exceeded the estimated receipts by some $14,000. At the close of the year, despite a` number of unexpected decreases in receipts, it had proved possible to accomplish substantially all the work laid out and close the books with the usual transfer of initia¬tion fees to the General Reserve, and still only reduce the cash balance $2,074 54. This was made possible by the hearty and loyal cooperation of the whole staff of employees and the extremely large amount of gratui¬tous service rendered by the officers, the members of the Divisions and technical Committees, and the membership generally Even so it was impossible, because of limitations of funds, to undertake many things it is highly desirable for the Institute to do, and it was necessary to refuse the publication of important papers and committee studies, because of the lack of funds.

Jan 1, 1923

By Robert B. Paul

This paper describes the new lead smelter and refinery recently completed by the American Smelting and Refining company in Southeast Missouri.

Jan 1, 1970

By W. H. Emmons

ALTHOUGH gold is one of the rarer metals, it is widely distributed; it is found on all of the continents and in each of the grand metallogenic provinces of the earth. It is prominent particularly in the shield areas of the earth; these areas have produced a large part of the world's lode gold and in most of them gold lodes are more important than the lodes of other metals. The Scandinavian shield is the only one that has not produced much gold. Nearly all of the world's gold has been derived from lodes and from sands and gravels where gold placers formed by the destruction of lodes. The gold derived from magmatic segregations, from pegmatites and from contact metamorphic deposits is quite subordinate to that derived from auriferous lodes. The lodes include all veins and related deposits that are formed by hot waters that move along fissures or other openings and that deposit vein matter in the fissures and by replacement of the country rocks along the fissures. All of the shield areas of the earth are characterized by large areas of granitic rocks including granitic gneisses, granodiorites and other acid intrusives which here are included in the general term "granite." The granites are intruded into schists, ancient lavas and other rocks which here are designated as the "invaded" rocks. The granites are parts of what once were great batholiths: that is, they are the remaining portions of great deep-seated bodies that slope outward, have very irregular roofs and so far as known have no floors but extend downward to great though unknown depths. Some of them are scores or hundreds of miles across and contain islands or "roof pendants" of the invaded rocks at places where the roofs of the batholiths were low-that is, where erosion has not yet completely unroofed the batholiths.

Jan 1, 1932

By F. E. Buch

The smelter is designed for a production capacity of 10,000 short tons of blister copper per month, when operating on the present concentrate grade. The :smelter lay-out is shown in Fig I. The major units of equipment comprise two reverberatory furnaces, three 13 by 30 ft Peirce-Smith converters, two straight line casting machines, one being served by a 13 by 30 ft holding furnace and the other by a ladle tilting quadrant, two converter aisle cranes and two converter blowers. The plant is compact and the general arrangement of standard gauge railway tracks and conveyor belts provides for a smooth flow of incoming materials and metallurgical products. Concentrate is received by conveyor belts and fluxes in standard railway trucks. The local track system is covered by an electric trolley locomotive. The Smelter treats a wet (10 pet moisture) flotation concentrate containing approximately 53 pct total copper and 0.9 pet oxide copper. The predominating minerals are chalco-cite, chalcopyrite and bornite accompanied by small quantities of malachite and cuprite. The gangue is highly siliceous and requires limerock as a flux. Metallurgy would be straightforward were it not for the necessity for eliminating bismuth which occurs as an impurity in the ore along with the copper. Directly or indirectly most of the Smelter problems can be traced to the necessity for bismuth removal. Copper recovery, based on new copper treated, averages 97.5 pct. General Description Flotation concentrate, containing 10 Pet moisture, is conveyed from the filter plant to the smelter storage bins by conveyor belts, the material being weighed in transit by a revolving drum type of weigh-hopper manufactured by Samuel Denison and Son, Ltd. The weigher consists of a steel drum with dished ends carried on a horizontal shaft and rotated by an 8 hp squirrel-cage motor through a worm and Spur reduction gear. A feed mouth in the drum permits of filling and discharging. The whole unit is supported on a framework resting on weighing levers, which in turn connect to transfer levers, thence to an indicator of the steelyard type situated 16 ft from the centre line of the drum. The indicator is of the "Denison" patent equilibrium controlled ticket stamping type, insuring mistake-proof records by a combination of electrical and mechanical movements which Prevent the operator from printing until the cover enclosing the steelyard is closed and until the poise-weights have been Set correctly to the weight of the hopper and contents. The machine is capable of weighing 30 short tons at a time but the usual load is 28 tons. After obtaining the gross weight the drum is rotated and discharged into a receiving bin situated below it. The empty drum is weighed and the net weight re-

Jan 1, 1949

By S. M. Marshall, A. C. Richardson, H. Y. Yancey

A year ago, Marshall and Bird presented a paper in which a new method of measuring the agglutinating power of coal was described.' The procedure used was to determine the strength of a button containing 10 parts sand and one part coal, formed by carbonizing the mixture in a crucible in an electric furnace. The result of the determination was reported as the total weight in grams required to bring about complete destruction of the button. Correlations were shown between the agglutinating value and some of the characteristics of the different coals that were investigated. This agglutinating test has been in use fairly continuously during the past five years for coals of widely differing coking qualities, and it has shown reasonably concordant results accurate enough for commercial use, although there are many features of the test which should have further scientific study. During the past year a study has been made of some coals of low coking strengths, and incidental to the main investigation some data which appear to be of interest and value were obtained on the loss in agglutinating power caused by exposure to the air. Three coals were investigated, all of which were of the Tertiary age; two were from one field in Asia, and one from a field in the United States. The three were similar, as shown by the proximate and ultimate analyses in Table 1 (moisture-free basis). Coals SA and RA generally contain about 5 per cent. moisture and coal P about 3.5 per cent. moisture on the as-received basis. The large difference in the ash contents of the coals, amounting to practically 10 per cent. between SA and RA, and P, makes difficult a direct comparison of their qualities. In the second section of Table 1 the figures have been put upon an ash-free basis., This table shows that these coals are closely alike. The ultimate analyses are almost identical except for the higher nitrogen content of

Jan 1, 1930

By F. W. Jessen

The Mechanism of solution of salt and mixed halites of sodium and potassium is reviewed. The variation in the rate of salt removal under both laminar and turbulent flow conditions is discussed. Many changes are possible in the development of solution cavities whether used for production of salts or for storage of hydrocarbons. The parameters influencing the type and shape of cavity formed with single well or multiple well systems are examined and information presented regarding field application of techniques developed and the means of controlling overall configuration of solution cavities.

Jan 1, 1972

By G. Herget, O. Garg

Trends will continue towards more automated, and sometimes larger mining and haulage equipment to reduce pit development and haulage costs. To save labour costs, larger capitalization of open pits is required and pit design and stripping ratios have to be firmed up at a very early stage of mine planning. Bench failures will assume a greater importance with larger equipment and at present we have only a limited capability of predicting stable slopes in complex structural geological settings. Deep open pits will pose particular problems in regard to high toe and floor stresses. This will require the development of more efficient systems for rock mass exploration and an improvement of our predictive capability in regard to pit slope stability and appropriate management of ground- water and materials. To meet the challenge, we have to improve: a) Analytical tools to assess slope stability in structurally complex settings as found in large open pits; b) Core orientation methods during diamond drilling operations; c) Geophysical logging methods to obtain geotechnical and structural geological information for large volumes of rock; and d) Geotechnical data handling systems to define mechanical properties

Jan 1, 1983

By A. D. Brokaw

The so-called "paraffin dirt" of the Gulf Coast oil fields has been considered an indication of the possible presence of oil and gas, and not a few wells have been brought in solely on the basis of such evidence. In a sense, it may be empirically justified as evidence of the presence of oil or gas, though it cannot be said to be infallible. If the writer is correctly informed, its association with oil and gas was pointed out by Lee Hager some years ago, and while it is commonly mentioned by geologists and operators in conversation, no discussion seems to have found its way into print. The present interpretation is based on laboratory study rather than on field investigation, and is put forth with the hope of stimulating discussion which shall lead to more complete understanding. The term "paraffin dirt" has been applied to soils with a peculiar texture, which has been described as "curdy" or "rubbery." When moist, the material breaks much after the fashion of "green" cheese. It is rubbery under compression, but does not resemble rubber in tenacity or cohesion. When dry, the material ranges from hard clods to a horny mass of high tensile strength. The shrinkage in drying is very great, especially in the hornlike matter. The moist material ranges in color from dark brown in the specimens rich in organic matter to grayish in specimens containing more inorganic matter. All of the specimens studied were readily attacked by molds, which in some cases grew in great profusion on the samples. Samples exhibited a rather characteristic "swampy" or "mucky" odor when wet, and a characteristic odor of humic soils when moist. If the material is brought into suspension in water, very fine sand settles out and may be recovered by successive washing and decantation. The sand is almost entirely quartz, but contains occasional fragments of feldspar—more or less kaolinized and iron-stained. Practically all of the sand passes through a 100-mesh screen and the grains are extremely sharp —possibly below the limit of rounding. A flocculent mud, of clay and organic matter, remains in suspension for days. Some material is taken into solution in the water, imparting a slight tendency to froth when vigorously shaken. The results of partial analyses of four samples of "paraffin dirt," and, for comparison, one of a coastal plain soil are given in Table I.

Jan 1, 1920

By Edwin F. Nelson, Charles Wirth, Gustav Egloff, C. D. Maxutov

The treatment of emulsified crude oils has been a problem for years in the petroleum industry. Until comparatively recently various methods of settling with and without chemicals have been used with indifferent success. Since wells have been acidized, emulsified crudes have been produced, which add considerably to the need for improved methods of treatment. The presence of large quantities of salts in the oils from acidized wells has presented several new problems to the industry. The use of hydrochloric acid in well treatments has caused the formation of sodium, magnesium, and calcium chlorides by interaction with the dolomitic limestones. These salts dissolve readily in the water normally present in the oil, and they are therefore incorporated in the emulsified oil. The crystalline salts have also been found in the oil, prevented from settling by protective films such as asphalt, resins and petrolatum. In some instances, free hydrochloric acid has been found. The salts may be present in crude oil in amounts ranging from a few pounds to over 1000 lb. per 1000 bbl. of oil. The transportation of these crude oils through pipe lines has led to erosive and corrosive effects, which are a tremendous cost to the petroleum industry. During 1937, more than 1,200,000,000 bbl. of crude oil was transported through pipe lines. Of this quantity approximately 10,000,-000 bbl. was water, and considerably more than 50,000,000 lb. was salts. If the crude oils were treated at the producing wells to remove the salts and water, an appreciable saving would be possible. The treatment would not be difficult, since it has been found that these oils are more easily treated at the time they are produced than after the aging and more stable emulsification that occur before they reach the refinery. Since great costs are involved in the use of these salty crudes at the refinery, treated oils essentially free of salts would naturally command a premium. The real added costs lie in refining salt-containing crude oils. Severe corrosion of refinery equipment in both topping and cracking installations has appeared in many refineries. Chemicals such as ammonia, lime and

Jan 1, 1938

R. W. Raymond, New York City: In connection with the subject of multiple tuyeres, my attention has been drawn to the practicability of gaining, without the multiplication of tuyeres, the advantages which that measure is intended to secure ; and learning that this had been attempted in the invention of the Gaines radial-discharge or fan-shaped tuyere, I wrote to Messrs. Gustafson Brothers, of Sequachee, Tenn., who manufacture that tugere, for information concerning the invention itself and its performance in practice. To their courtesy I am indebted for most of the facts given below. I present these statements without expressing any personal opinion on the subject (having no personal knowledge of it), for the purpose of bringing this device to the notice of members, and calling forth both criticism and testimony concerning it. Admitting that definite advantages are to be secured by the multiplication of tuyeres, we must still confess that this change involves considerable expense in the increased number of blastpipes, tuyeres, coolers, connections, and pipes for water-circulation. There is, moreover, a serious question involved in the weakening of the furnace-wall by extra perforations. This consideration applies with special force to furnaces already built without reference to such an increase of tuyere-openings. Ledebur, in his Handbuch der Eisenhüttenkunde, says on this point (I translate from the edition of 1893, page 365): "A limit to increase in the number of tuyeres is given, in any case, by the circumstance that the perforation of the wall weakens it; in other words, that there must be left between the tuyeres a mass of masonry sufficient to carry the parts above. In most cases an appropriate number may be secured by giving to the furnace as many openings as there are meters in its circumference at the tuyerelevel. For instance, for a hearth-diameter of 2.5 meters, i.e., a circumference of 7.7 meters, seven or eight openings might be made, of which, however, one would

Jan 1, 1899

By Hassell E. Hunter

The Wyoming Minerals - Conoco Crownpoint Joint Venture represents the first time that big hole drilling has been exclusively used to develop a privately financed mine. Three shafts, one ten feet in diameter and two six feet in diameter, have been successfully drilled to depths of 2243', 2188' and 2188' respectively and lined with hydrostatic designed steel casing. The largest shaft is to be used to as a development shaft to handle muck and water from enlargement and station excavation of the other two shafts. A reverse fluid air assist circulation system with potassium base mud was used during drilling. The mud was cleaned by settling in steel lined tanks with assistance from cyclone type sand separators. Deviation was monitored with wireline gyroscopic surveying instruments at 30 foot intervals. Horizontal departure did not exceed 16 inches off perpendicular. Casing was designed to withstand full hydrostatic pressures with a 1.5 safety factor for the large shaft and 1.25 safety factor for the two smaller shafts. All casing welds were x-rayed prior to lowering the casing into the hole. Cementing the annular space completed the operation. The total time to mobilize, drill and move off the three shafts was 363 days. The drilling operation was completed ahead of schedule and under budget.

Jan 1, 1982

By C. B. Murray

"OUR experience from time immemorial has been that the furnace sampler and analyst usually find one or two, and sometimes more, points less iron than the Lake Superior shippers, but, fortunately, their contracts are `iron bound'; and, generally speaking, analyses at this end are practically useless, for we are obliged to settle on basis figured out to a half dozen decimals, and, as a rule, without recourse in the event of flagrant discrepancies between the two analysts." The above is an extract from a letter received by the writer of this paper from the President of an iron company, discussing the question of sampling. It so well expresses the opinion of many blast-furnace owners and managers that it seems a suitable text for a discussion concerning the need of uniform methods of sampling. If all railroad cars were loaded the same, if all stock piles were the same shape, and if ore was received regularly each day, the problem of sampling would be comparatively simple. The conditions, however, vary widely at different places, and at the same place from day to day, and it is probably impossible to determine upon any one method of sampling which will apply at all times and in all cases. However, it would seem as though some general principles might be suggested which would tend to overcome these wide differences in samples of the same thing. The sampling of a cargo of iron ore begins at the breast of ore in the mine. The ore is sampled from the mine cars, from the stock piles, and from the railroad cars at the mines. At the lower Lake ports the ore is practically all sampled from the boat, occasionally from railroad cars. At the furnaces, the ore is nearly all sampled from railroad cars and occasionally from stock piles.

Jan 1, 1914

By G. W. Brownell, H. T. F. Lundberg, R. W. Pringle, K. I. Roulston

The rapid improvement of the airborne scintillometer and the perfection of its efficiency for counting low energy gamma radiation has made it possible to work out a technique to map in great detail the radiation pattern at the earth's surface. On such maps low radiation over certain areas appears to indicate the existence of oil accumulations, forming a pattern similar to that obtained by the geochemists.

Jan 12, 1953

By F. D. Rosi

IN the production of single crystals by the Bridg-man method of solidification from the melt in vacuum at a crucible lowering rate of 0.25 in. per hr, a cellular structure was frequently observed in copper and copper-base alloys at the terminal surface of the as-cast crystals (i.e., the surface representing the last portion of the crystal to solidify). The geometrical form of this structure varied from crystal to crystal, but, in general, could be classified as either hexagonal or quadrilateral. Fig. 1 shows examples of this cellular structure, which is similar to that reported by Buergerl and, more recently, by Pond and Kessler&apos; and Rutter and Chalmers. In the micrographs of Figs. lb and c, the cubic structure in the alloy crystals is obscured somewhat by excessive surface evaporation in the final stages of solidification. X-ray orientation studies indicate that the traces outlining the various geometrical forms correspond to octahedral planes, which are the planes of greatest reticular density in the face-centered cubic lattice. It would appear from this that the view first propounded by Bravais,4 that the surface energies and normal growth velocities of the different crystal planes are inversely proportional to their reticular densities, applies to this cellular structure, since those surviving are the planes of greatest atomic density. Thus, the observed variation in the geometrical form of this structure in crystals of different orientation is readily understandable from the distribution of the (111) planes in the standard {111}, (1101, and (1001 stereographic projections. Depending upon whether the crystal axis (i.e., the direction of crystallization) coincides with a <111>, <111>, or <100> direction, the cellular structure viewed from a surface perpendicular to the crystal axis will consist of a network of regular hexagons, skewed hexagons (with interfacial angles of 110" and 125"), or cubes, respectively. It follows, moreover, that off-orientations from these principal directions will yield modifications of these three basic geometric configurations. In this connection, it is interesting to note that the bounding planes of the hexagonal structure observed in tin by Rutter and Chalmers3 showed no preferred orientation.

Jan 1, 1954

The first mention of the mining and use of coal in the Pittsburgh district refers to the mine under Duquesne Heights that furnished coal for the garrison at the fort at Pittsburgh in 1760. Coal had been dug and used as fuel just outside of Brownsville, Fayette county, in 1759, but this was not a regular mine as the opening was in an outcropping. Maps of Ohio in 1770 showed "Cole Mines" at various points. The Penns purchased all the coal south of Kittanning in southwestern Pennsylvania from the Chiefs of the Six Nations for a reported price of $10,000. During the Revolution, coal from Herron Hill, Mincrsville, and Coal Hill, all within the present city limits, was used in Pittsburgh. There is today one custom pit opened in Coal Hill (Duquesne Heights). The first steam engine was set up in Pittsburgh in 1794 and used coal as fuel. The first mine in the Youghiogheny gas district was opened in 1796. In 1803, the first shipment of coal by water was made from Pittsburgh down the Ohio river and landed at Philadelphia, where it sold for approximately $9.50 per ton. The mines along the Monongahela were naturally the first to be opened. With the completion of locks and dams in 1844, permitting slack-water navigation, the industry began to thrive. The No. 8 field of Ohio and the Fairmont region of northern West Virginia were opened in the period 1840 to 1855. From that time on there has been a continuous development of the coal rcsources of this district, until at present productive capacity is enough to supply 30 per cent. of the country&apos;s needs of bituminous coal. The original method of working the Pittsburgh seam was to drive under cover at some easily accessible point on the outcrop with a single entry, usually 1½ yd. wide. Rooms or gangways were turned to the right and left from this entry and ventilation was usually poor and inade-

Jan 1, 1927

By A. E. Gorum, I. Cornet

Fatigrle of ionic crystals has been studied primarily in magnesinm oxide. under cyclic stress dislocations move irrreversibly; they multiply; slip bands form and grow; cracks mucleate and propagnte, and failure occurs. The use of ionic crystals such as MgO is advantageorus in such investigations because they are optically transparent. Individual dislocation Intersections with {100} surfaces may be observed with a standard microscope, using etch-pit techniques. Slip, deformation, crack .formation, and fracture in MgO crystals under cyclic stress are compared with cotrresponditzg processes in metals. ThE effect of cyclic loading in metals has been studied for many years. The appearance of slip lines is readily observed and the ensuing fracture may also be seen. From these observations it is possible to predict the behavior of a material and make an educated guess as to what is happening internally, but the actual changes taking place within the structure are not readily apparent. If one could obtain a material in which the individual glide components could be observed, it would be invaluable in determining the actual slip distribution resulting from cyclic loading as well as the distribution of slip in the neighborhood of a growing crack. Such a material is magnesium oxide. Dislocation arrays may be observed by means of etch pits

Jan 1, 1961

By C. A. Rowland, M. D. Flavel

There are seven basic comminution circuits that can be used to prepare beneficiation feed from the product of a primary crusher. This paper gives a comparison of these circuits based on average process and economical data. The paper is principally devoted to a discussion of the test work required to obtain the process data needed to evaluate each circuit. The results of the test work in conjunction with geographic and economic factors can be used to narrow down the choice of possible circuits to one, two, or three before making a detailed engineering study.

Jan 1, 1985