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By J. F. Myers

AT the Regional meeting in Columbus, Ohio, in September 1949, the authors presented a progress report of the first year's operation with a Hardinge tricone mill in closed circuit with a Dorr hydroscillator. The present report covers our findings on this grinding circuit to January, 1950. In order to clarify our position, the authors wish to state that no invention or discovery is claimed. The Tennessee grinding circuit is simply an engineered arrangement of known equipment arranged to incorporate all of the recognized efficiency factors of comminution as they are known today. As we concluded our first report, it was not clear how effective the Tennessee mode of operation would be on harder ores. The only information we had at that time was that the Bond grindability test at 48-mesh gave 6.04 g of undersize per revolution. A later test on the same sample at 100-mesh reduced this to 2.04 g, which is definitely in the harder ore class, and which makes the reported 8.80 kw-hr per ton of -200-mesh produced a very creditable figure.

Jan 1, 1950

By O. C. Wheeler

In order that the series of reports on oil and gas in Colombia may be complete, the report for the year 1941, which was not available for Volume 160 of the TRANSACTIONS, is given here. The report for 1945 begins on page 4o6.

Jan 1, 1946

By P. D. I. Honeyman

DURING 1938 many copper companies again felt the economic pinch and smelter operations were often on a reduced basis which some- times resulted in intermittent operations and complete shutdowns. During the last half of the year production was stepped up and smelting operations resumed a more normal appearance. One of the present-day trends in reverberatory sme1ting is definitely toward high-tonnage operations. i\ t the Phelps Dodge Corporation's Douglas plant, the reconstructed 107 by 26- ft. reverberatory furnaces are operated at the rate of 1000 tons of solid charge per day. The arch, all of silica brick; is sufficiently high above the bath to give

Jan 1, 1939

Aamot, Olav Crone, (Member '29) Met , Det Norske Aktieselskab for Elektrokemisk, Industry, Inc , Oslo, Norway Aase, Glenn D , (Junior Member '40) Met Engr , Western Research Dyv , American Smelt & Refin Co , Selby, Calif Abadye, Henry G., (Member '43) Petr Engr , Sr Prod Engr , Long Beach Oil Development Co, 255 So Santa Clara Ave, Long Beach, Calif Abbott, Clarence E , (Member '04) Civil Engr , 'P , Tennessee Coal, Iron & R R Co , 1542 Brown Marx Bldg Birmingham, Ala Abbott, Fred E , Jr , (Member '44) Petr Engr , c/o Arabian American Oil Co , A P 0 816, c/o Postmaster, New York, N Y Abbott, John H , (Member '46) Resident Mgr , Hickman, Williams & Co, 230 No Michigan Ave, Chicago 1, Ill Abbott, R W R., (Member '47) Asst Power Supt, Cananea Consolidated Copper Co , Cananea, Son , Mexico Abbott, Robert H? Jr., (Junior Member '47) Petr Engr, Producing Dept, The Texas Cc, P 0 Box 951, Houma, La Abel, Raymond L., (Member '28) Chem Engr, Prof of Chem Engrg, Univ of Pittsburgh, Pitts¬burgh Pa Abel, Walter D , (Member '32) Min Engr, Div of Corporations, 403 State Bldg , Los Angeles 12, Cal if

Jan 1, 1952

The Institute has prepared a list of Societies' publications, magazines, . etc., which were duplicates and were discarded at the time of the consolidation of the libraries of the three Founder Societies. These books will be disposed of about March 1, 1916 by the Board of Directors of the Institute through the Library Committee. If, meanwhile, members who have incomplete sets of these books, or for any other reason desire to secure some of them, they are asked to communicate immediately with the Secretary, as this is in unusual opportunity to secure books at a very low price. American Gas Light Journal, viols. 31 to 39. American Institute of Electrical Engineers, Transactions, vols. 5 to 26. American Machinist, vols. 3 to 20, 22 to 29. American Society of Civil Engineers, Transactions, vols. 2 to 10, 21 to 24, 26 to 33, 39 to 49, 52, 55, 58, 74. Index, viols. 1 to 21. American Society of Mechanical Engineers, Transactions, vols. 1 to 28. Index, vols. 1 to 20, vols. 1 to 25.

Jan 1, 1916

By A. Hultgren, G. Phragmén

Page Outline of Progress of Knowledge and Theories about Gas Evolution in Steel Ingots. and Its Influence on Crystallization and Segregation................ 134 Object of Present Investigation........................................... 148 Theoretical Discussion of Process of Solidification........................... 149 Gas Given Off from Rimming Steel during Solidification................... 149 Equilibrium Diagram of the Iron-carbon-oxygen Alloys................... 151 Solidification of Pure Iron-carbon-oxygen Alloys.......................... 157 Solidification when Carbon Monoxide Is Given Off at Constant Pressure... 157 Solidification when Gas Evolution Is Suppressed....................... 158 Schematic Application on Solidification of Rimming-steel Ingots.......... 159 Influence of Manganese, Sulphur and Phosphorus......................... 160 Experimental work..................................................... 162 Liquid Steel and the Mold Gas......................................... 162 Ingots Investigated and Methods Used.................................. 165 Ingot structure....................................................... 174 Structure of Rim Zone.............................................. 174 Structure of Core................................................... 181 Structures Obtained under Special Conditions of Freezing................ 182 Distribution of Metalloids............................................. 187 Other Observations Made............................................. 192 General Discussion of Solidification Process................................. 195 Condition of Liquid Steel before Casting................................. 195 Rimming Period...................................................... 202 Composition of Rim Zone............................................. 225 Freezing after Top Is Closed........................................... 228 Slag Inclusions and Ingot Scum........................................ 234 Reaction between Gas in Blowholes and Surrounding Solid Steel during Cooling 235 Summary.............................................................. 237 Appendix—Preparation and Etching of Ingot Sections....................... 238 References............................................................. 239 In 1934, Jernkontoret (The Swedish Ironmasters' Association) appointed a committee for the study of the structure of rimming-steel ingots and the various phenomena associated with their solidification. The members of the committee, including those who have joined it later, have been: I. Bohm, B. D. Enlund, B. Kalling, M. Tigerschiöld, S. Wohlfahrt and the authors. The present paper‡ is a somewhat

Jan 1, 1939

By G. Phragmén, A. Hultgren

Page Outline of Progress of Knowledge and Theories about Gas Evolution in Steel Ingots. and Its Influence on Crystallization and Segregation................ 134 Object of Present Investigation........................................... 148 Theoretical Discussion of Process of Solidification........................... 149 Gas Given Off from Rimming Steel during Solidification................... 149 Equilibrium Diagram of the Iron-carbon-oxygen Alloys................... 151 Solidification of Pure Iron-carbon-oxygen Alloys.......................... 157 Solidification when Carbon Monoxide Is Given Off at Constant Pressure... 157 Solidification when Gas Evolution Is Suppressed....................... 158 Schematic Application on Solidification of Rimming-steel Ingots.......... 159 Influence of Manganese, Sulphur and Phosphorus......................... 160 Experimental work..................................................... 162 Liquid Steel and the Mold Gas......................................... 162 Ingots Investigated and Methods Used.................................. 165 Ingot structure....................................................... 174 Structure of Rim Zone.............................................. 174 Structure of Core................................................... 181 Structures Obtained under Special Conditions of Freezing................ 182 Distribution of Metalloids............................................. 187 Other Observations Made............................................. 192 General Discussion of Solidification Process................................. 195 Condition of Liquid Steel before Casting................................. 195 Rimming Period...................................................... 202 Composition of Rim Zone............................................. 225 Freezing after Top Is Closed........................................... 228 Slag Inclusions and Ingot Scum........................................ 234 Reaction between Gas in Blowholes and Surrounding Solid Steel during Cooling 235 Summary.............................................................. 237 Appendix—Preparation and Etching of Ingot Sections....................... 238 References............................................................. 239 In 1934, Jernkontoret (The Swedish Ironmasters' Association) appointed a committee for the study of the structure of rimming-steel ingots and the various phenomena associated with their solidification. The members of the committee, including those who have joined it later, have been: I. Bohm, B. D. Enlund, B. Kalling, M. Tigerschiöld, S. Wohlfahrt and the authors. The present paper‡ is a somewhat

Jan 1, 1939

By John Birkinbine

(New Haven 'Meeting, February, 1909.) AWAKENED public interest in efforts to conserve natural resources will certainly be appreciated by the members of the American Institute of Mining Engineers, and a discussion upon conservation may well form a part of one of the Institute meetings, for the records of papers and discussions which appear in the 38 volumes of its Transactions are replete with evidence of effort's in this direction. Every process which reduces the fuel consumed or the power applied per unit of product; every utilization of waste material, or employment of that formerly rejected, to obtain something of value ; every feature of construction or operation which lessens the labor required or increases the output per employee, is an advance in the direction of true conservation. This may not appear from the records of late conferences or from published articles, in which the effort seems to be concentrated upon reducing the consumption and presenting to the people of the country estimates of exhaustion of natural resources. I rejoice in the awakening of public interest in a matter so important for the present and future welfare of our nation; I appreciate the possibility of much good following conferences of the Governors and delegates from various States and from national societies; and I recognize the interdependence, not only of different States, but of contiguous nations. In fact, the marvelous development of transportation by land and by water, and the decreasing rates at which commodities can be moved great distances, have in many cases practically obliterated geographical boundaries, and nearly every country on the globe can either market its product in other lands or draw upon them for raw or manufactured materials ; hence, conservation is an international subject.

Apr 1, 1909

By A. J. Stosick, J. R. Hoffman, E. Rudy, St. Windisch

The binary alloy system Mo-C zoas investigated by means of X-ray, metallog/aphic, thermoanalytical, and melting-point techniques on chemically analyzed specimens. The system, Fig. 39, is characterized by three congruently melting, intermediate phases, Mo2C, n MoCi-x, and aMoC1-,, of which only Mo,C is stable at temperatures below 1650°C. Substoichio-metrzc (~32.5 at. pct C) dimolybdenum carbide undergoes a homogeneous sublattice order-disorder transformation at temperatures of approximately 1400°C, whereas hyperstoichiorrletric compositions undergo a discontinuous Phase change. The order-disorder transitions in the Me, C phases are discussed in terms of the structural changes involved in the transformation processes and the absence of long-range sublattice coherency in stoichiometric or hyperstoiclziomet-ric compositions attributed to the impossibility of obtaining long-range order in a linear chain of alternating carbon atoms and vacancies. From the experimental phase relutionships and the known thermody-namic data for Mo2 C, limits for the free energies of formation for the high-temperature phases r) MoC1-, and aMoC1-, are deriued and found to be in good agreement with data previously obtained from phase equilibria in ternary metal-carbon systems. IN the course of studies of the high-temperature phase relationships in ternary systems of refractory transition metals with carbon,' a number of inconsistencies found in previous work necessitated a reex-amination of some of the related metal-carbon binaries. A reassessment of the binary system data also seemed

Jan 1, 1968

By Richard H. Mote, W. C. Schroeder

The endlessly changing pattern of mineral supply and demand offers opportunity to the alert and can bring disaster to the unwary. The discovery of ore bodies, the invention of extractive processes, the provision of new transport facilities, the political stabilization of underdeveloped areas, and many other changes can increase supply dramatically. Such new outpourings of mineral wealth from ore bodies bring fortunes to their developers, and consumers frequently find their competitive positions decidedly improved by new and cheap sources of supply. On the other hand, operators of marginal properties can find competition from newly opened high-grade mines intolerable. Consumers that have depended on the products of nearby, high-cost mines may find new, remote, low-cost supplies advantageous only to their competitors. The invention of new prospecting methods can have spectacular effects. Shortly after World War I the discovery rate of petroleum pools began to decline. The leading prospecting technique of that day, the projection downward of surface reflections of geologic structure, was proving less rewarding. Prophets foretold an oil shortage in the near future. But at that very moment scientists were perfecting the application of seismic waves to reveal underground oil-bearing geologic structures. As these geophysical methods were put into commercial use the whole outlook changed-the problem of the 1930's became how to cope with the surplus from discovery, not how to meet the ever rising demand. Many lead mines were being abandoned as unprofitable about this same time because the penalties charged by smelters for the zinc in the ores and concentrates more than counterbalanced the payments for lead and silver. Then selective flotation (at the time called differential flotation) appeared,

Jan 1, 1959

Bernard MacDonald, Guanajuato, Mexico (communication to the Secretary*):—Mr. Iceyes's paper is very interesting to me because of my personal experience with the development of the ore-deposits of Lake Valley.

Jan 1, 1909

pAbad, Leopoldo F., Min, Engr,, Div. of Mines, Bureau of Science Manila, P. 1. '23 Abadilla, Quirico A,, Geol., Lago Pet. Corp Box 172, Maracaibo, Venezuela, '20 Abbey, Robert Graham, The W. W. Sly Mfg, Co Train Ave., Cleveland, Ohio. '21 Abbott, A. N., Mines Supt., Mazapil Copper Co., Ltd Concepcion del Oro, Mexico, '28 Abbott, Clarence E., Mgr., Mines & Quarries, Tenn, Coal, Iron & R. R, Co,, 1242 Brown Marx Bldg,, Birmingham, Ala. '04]

Jan 1, 1928

By C. A. Stetefeldt

FoR the convenience of those who do not care to enter into the details of this long essay, I begin with a summary of the most important results it presents. The extraction of silver by the lixiviation-process from ores which have been subjected to a chloridizing-roasting, is based upon the fact that silver chloride is easily soluble in solutions of sodium or calcium hyposulphite, and that silver is precipitated from such solutions by an alkaline sulphide, with regeneration of the hyposulphite salts. In case the ore contains lead a large portion of the latter is and dissolved, lead sulphate being soluble in hyposulphite solutions. If, at the same time, copper is present, the sulphides precipitated from the solution, contain silver, copper, and lead, a combination of metals not desirable for subsequent treatment. Mr. E. H. Russell, of Park City, Utah, is the inventor and the patentee in the United States and several foreign countries of a new lixiviation-process, based upon the chemical facts discussed in this paper. Mr. Russell has discovered that lead can be completely separated from a sodium hyposulphite solution, as lead carbonate, by sodium carbonate or purified soda-ash, without precipitating any copper or silver. After decanting the solution from the lead carbonate, silver and copper are obtained from it in the usual way. This method of separating lead prohibits the use of calcium poly-sulphide as a precipitant for the sulphides, because any calcium entering the regenerated lixiviationsolution would also be precipitated as a carbonate with the lead by soda-ash. Hence, a sodium sulphide must be employed. A full investigation has demonstrated that this is by no means detrimental. Sodium sulphide and hyposulphite are more advantageously used in the lixiviation-process than the corresponding calcium-salts. Another defect in the lixiviation-process consisted in the necessity of a very perfect chlorination of the silver in the ore, because silver in

Jan 1, 1885

By Percy A. Robbins

I. INTRODUCTION. THE central power-station. of the De Beers Consolidated Mines, Ltd., was designed and built under my supervision about five years ago. Since no detailed description of this plant has ever appeared, it may possess sufficient interest to warrant its publication, even at this late date. Although some additions may have been Blade to the plant, the following account, prepared from my notes, and accurate up to May, 1905 (at which time I severed my connection with the De Beers Com¬pany), will, I think, be found substantially correct. Certain local conditions governing the design of this plant should be stated first. If. GENERAL CONSIDERATIONS. The climate is hot and dry. The .region around Kimberley is arid and water is very scarce. The supply obtained from the mines contains so much material in solution that it is unfit for use in boilers or condensers (although tests recently made with a water-softening plant, built by Hans Reisert, of Germany, would indicate that water thus treated is suitable for boilers). And the amount of water required for concentrating about 30,000 tons of ore per day is so large that the question of adequate water-supply for this power-station had to be carefully considered. The rainy season extends from December to April, and the rainfall averages about 15 in. per year. Droughts are frequent; and in some years there is scarcely any rain at all. The water-supply for the town of Kimberley is brought from the Vaal river, 16 miles distant, and pumped into town by a private water company. The charge made for water, which is

Mar 1, 1908

By K. A. ACKLEY

The petroleum industry experienced a year of satisfactory accomplishment in Oklahoma during 1945. Crude oil production was increased, a new record for recent years was established in well completions, and refinery operations were maintained at a maximum level. Daily average crude oil production increased to 382,000 bbl., reflecting a 13.5 per cent gain compared with production during the previous pear. Total wells drilled during 1945 amounted to 2556, a gain of 28.7 per cent over 1944 Refinery throughout averaged 187,500 bbl. daily, an increase of approximately 4 percent over the preceding year.

Jan 1, 1946

By C. H. Mathewson

MY treatment of the subject of "Metals of the Future" is imaginative rather than statistical or scientific, because reliable information concerning useful concentrations in the form of ore deposits of by far the majority of the elements does not exist and the chemical, physical, and mechanical properties of the unfamiliar metals are recorded only in fragmentary and uncertain form or not at all.

Jan 1, 1944

By FRANK FIRRISTONE

Ix the summer of 1842 my father, William Firmstone, was engaged by Charles Jackson, Jr., of Boston, to examine the conditions in the Lehigh valley as a site for blast-furnaces using anthracite for fuel. In consequence of his report, he was further engaged by Mr. Jackson to build a furnace for him and his partners on the Lehigh canal, 2 miles above the mouth of the river at Easton. Work was begun in the fall of 1842, and the first furnace blown-in in 1844. The history of the works, therefore, from 1844 to 1887, when my own connection with them ceased, covers only four years less than the whole period of the rise, culmination, and commencement of the decline in the smelting of iron with anthracite in America, the beginning of which, in a commercial sense, may be put in 1839.' Although this paper, as the title indicates, is concerned almost exclusively with the furnaces at Glendon, still what was done there was more or less influenced by current opinion in the dis¬trict, and even reflects, to some extent, the changes in opinion and practice with mineral fuel the world over. No. 1 Furnace was built of red brick, on four piers, had three tuyeres and fore-hearth and tymp, as was universal with furnaces using mineral fuel until the introduction of Liirmann's cinder-tuyere. The dimensions and profile are shown in Figs. 1 and 2. The first hearth (Fig. 1) was of sandstone; all after were of fire-brick (Fig. 2). The profile was no doubt derived directly from Gibbons's furnace,2 for it appears from W. Firmstone's note-books that in October, 1840, he visited ." Gibbons' new furnaces building at Corbyn Hall," and I have an old drawing,\

Sep 1, 1909

By A. W. Fahrenwald

Flotation practice in Idaho is now about 13 years old. The advance has been steady during these 113 years. The operators have been alert to take advantage of the newest developments and they have themselves made a constant effort to improve their work. The metallurgical improvements are due to the development of (1) better equipment, (2) better reagents, and (3) better understanding and control of the process. During the eight years the writer has been in this district, there has been continuous experimentation by several companies to improve the ore dressing by flotation methods. Gravity concentration has fought hard to hold its place, and although it is true that gravity processes have been improved during this period, nevertheless, in several of the important mills of the district the few tables that managed to hang on have finally given way. On the straight-lead ores, tables and jigs are still used; and, due to better classification, their hold on this job has been strengthened. Ores of the District The ores of the district are of two general classes: (1) clean lead ores, such as those from the Bunker Hill and Hecla mines, and (2) complex lead-zinc ores. The general impression prevails that the clean lead ores, class 1, are simple and that it is easy to obtain high recoveries and good grade products. This, in a way, is a false impression; there is quite a high percentage of locked middling in these ores at 100 and' 150-mesh sizes. Improved classification preparatory to table treatment of this type of ore has made it possible to segregate effectively a high-grade middling which is further comminuted and floated. The complex lead-zinc ores of the district, of which the ore from the Morning mine of the Federal Mining & Smelting Co. is a typical example, always have presented a difficult problem. It always has been comparatively easy to make a clean lead concentrate, but it never has been possible to concentrate sphalerite with a specific gravity of 4.10 from siderite of gravity 3.88. Also, a large percentage of the galena and sphalerite of this class of ore refuses to separate out until the crushing has been carried

Jan 1, 1928

By T. H. Oxnam

INTRODUCTION. THE predominating value of the ores now being treated by the Palmarejo and Mexican Gold Fields, Ltd., is silver, although some gold is also carried. The present method of treatment consists of wet-crushing and concentrating, followed by the cyanidation of the unroasted sands and slimes. The sands are treated by leaching and the so-called accumulated slimes by a system of agitation and decantation. It is only within very recent years that the cyanidation of unroasted silver-ores has been commercially successful. In fact, at the time operations were begun at the cyanide-plant at Chinipas, February, 1902, I knew of no other leaching-plant treating similar ores successfully. The cyanide treatment of the Palmarejo ores differs but little from the ordinary practice in cyaniding gold-ores; and perhaps but little, if any, new information concerning the metallurgy of silver is to be gleaned from it. PALMAREJO MINE. The Palmarejo mines are located in the southwestern part of the State of Chihuahua, Mexico, on the foothills of the Sierra Madre mountains, at an elevation of 3,200 feet. The mills, 12. miles distant, are situated on the Chinipas river, near the town of Chinipas, which is about 150 miles northeast of Agiabampo, on the Gulf of California. Supplies are shipped via this port as this route is the best and most direct to the property. The ore-bodies in the Palmarejo mines have been deposited. along a series of rock-fractures, caused by an intrusion of eruptive rock. The most important of these fractures or fissures, both in width and value, are the Prieta and Blanca veins, which.

Jul 1, 1905

COUNCIL OF ECONOMICS OF AIME Formerly Mineral Economics Division Established as a Division December 15, 1948 Established as a Council February 26, 1957 Franz R Dykstra, Chairman Paul Schultz, Vice-Chairman A J Phillips, Vice-Chairman Douglas Donald, Vice-Chairman J S Vanick, Contact AIME Director A H Lindley, Jr, Secretary-Treasurer Lehman Brothers 1 William Street New York 4, N Y COUNCIL OF EDUCATION OF AIME Formerly Mineral Industry Education Division Established as a Division January 15, 1932 Established as a Council February 26, 1957 0 Cutler Shepard,Chairman Lysle E Shaffer, Vice-Chairman John C Calhoun, Jr, Past Chairman J C Kinnear, Jr, Contact AIME Director J D Forrester, Secretary-Treasurer College of Mines Univ of Arizona Tucson, Arizona

Jan 1, 1958