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By J. W. Moody

The first Rodpeb mill ever built and placed in full scale successful operation went onstream in mid- 1960 at Marquette Cement Manufacturing Co.'s newly modernized portland cement production plant at Nashville, Tenn. It replaced a third stage of fine crushing and two 7x22-ft Compeb mills in the wet raw slurry grinding department. The Rodpeb mill at Nashville is similar in appearance to a Compeb mill but is larger. The mill, which operates in open circuit, is 9 ft in diameter and 38 ft long. The rod compartment is 12 ft long, with the rods being 11.5 ft in length and ranging in diameter from 4 in. down to about 1 in. The weight of the rod charge is 100,000 lb. The liners of the rod compartment are of the Lorain design.

Jan 4, 1963

By H. T. Mulryan

For the producer of industrial rocks and minerals, marketing is often the only means of survival. His material must be sold. There is little of the impersonal force of the market regulating supply and demand. No commodity exchanges facilitate his efforts to dispose of the material he produces, and the success or failure of his business depends primarily on prompt and correct response to market needs and requirements. This response is particularly vital where materials of low unit value must be shipped to distant consumers owing to a relative rarity of suitable deposits. The advantage of positive response to change can best be illustrated by hypothetical cases showing how problems can be turned into opportunity through marketing ingenuity. Three such cases dealing with materials of unit values in the range of $5 to $100 per ton are outlined below.

Jan 7, 1969

By Benny Langston, Frank M. Jr. Stephens

IN recent years much attention has been given to recovery, treatment, and disposal of dusts discharged into the atmosphere from operations of industry. Considerable data has been accumulated on both operational1-4 and design5,6 of dust-collector equipment for commercial installations. On the other hand, there is almost no published data on design and construction of small-scale equipment to handle dust problems that arise in the ore-dressing laboratory. Dust-collection equipment such as multiclones, single-cyclones, scrubbers, chemical and mechanical filters, settling chambers, and electrostatic separators has proved its efficiency for collecting dust in industry. In the laboratory, however, the engineer is faced with the problem of collecting small quantities of dust, inexpensively, without diverting the major effort from the metallurgical problem to the problem of collecting dust produced by the process.

Jan 8, 1954

Weston Portable Electrodynamometer The Weston Electrical Instrument Co. of Newark, N. J., believes that problems hitherto considered impossible of solution in the designing of portable electrodynamometers have been solved in its new models. The voltmeter, Model 341, is an instrument' of precision adapted to use on alterating- or direct-current circuits, guaranteed to an accuracy of 0.25 per cent. full-scale value either on direct or alternating-current circuits of any frequency to 133 cycles per second and commercial frequencies even as high as 500 cycles per second with very slight error. The polyphase electrodynamometer, Model 329, is accurate to 0.5 per cent. under the same conditions.; Double ranges are furnished in all instruments of this model. All current ranges can be used for 100 per cent. overload indefinitely without introducing error in Models 310 and 329.

Jan 12, 1915

By André G. Journel

Geological study of the Prony Nilaterite (New Caledonia) began in 1969 and included drilling, geological mapping and laboratory studies. The deposit is the product of weathering of basic rocks. From top to bottom, the following zones can be distinguished: a compact ferruginous cover; ore associated with yellow laterite, containing 1.0-1.5% Ni and low in impurities (SiO2, Mg); an intermediate silicated ore containing 1.3-2.0% Ni and higher percentages of impurities; garnierite ore much richer in nickel (2-4%) but high in SiO, and Mg contents (Mg up to 20%) ; and parent rock, largely peridotites. Distinction between types of ore is essential because the high grade ore (silicated and granierites) is penalized for its high Mg contents that demand additional acid treatment. All studies made distinguish two types of ore, laterite and silicated.

Jan 10, 1973

By C. C. Harris

The Gaudin-Meloyl equation for the size distribution of fragments resulting from single fracture is where y is the mass fraction of material smaller than size x, and x, and r are parameters to be determined from the experimental data. In physical terms, r is associated with the number of active flaws in a particle of characteristic dimension xo . The special attribute of this equation is its emphasis on the coarse size region of a distribution. There are various procedures2-5 for obtaining the parameters in Eq. 1, but a simple graphical method is awaited. This situation contrasts sharply with that in the cases of the familiar Gates-Gaudin-Schuhmann and Rosin-Rammler equations.6 The purpose of this note is to present a method based on a procedure7 which has been successful in several other applications.8-13

Jan 1, 1967

By D. G. Peterson, W. J. Guay

The extraction of gold from refractory ores containing activated carbon and various types of carbon compounds is being done commercially for the first time at Carlin, Nev., by Carlin Gold Mining Co. Oxidation of the carbonaceous materials to CO and CO,- is accomplished by the introduction of chlorine into an aqueous pulp. The chlorine reacts with the limestone in the ore to form calcium hypochlorite which in turn reacts with the carbonaceous matter to form calcium chloride, CO, and CO.. Following the oxidation treatment the ore is cyanided in the conventional manner. For the first six months of operation the plant averaged 83% extraction at a feed rate of 500 tpd and a consumption of 28.4 lb chlorine per ton of ore which showed only 33.5% extraction by conventional cyanidation without the oxidation pretreatment.

Jan 1, 1974

By L. Moussoulos

Pyrite concentrates produced at the Olympias mines, Northern Greece, show an unusually high gold and silver content (16-20 and 25-40 ppm respectively), associated with the presence of arsenopyrite; their high As content (5-8%) has hindered their utilization so far. In the present paper a simple and environmentally safe method that permits their complete utilization for the production of SO2 gas, As203, and the recovery of Au and Ag is described. According to this method, the pyrites are subjected to a single-stage oxidizing roasting in a fluid bed reactor. The precious metals, and approximately 45% of the contained As, remain with the cinders, while the rest of the As is removed with the SO2 - bearing gases and can be recovered by suitable treatment. The gases, after further cleaning, can be utilized for the production of sulfuric acid.

Jan 1, 1984

Sec. 1. The membership of the Institute shall comprise six classes, namely: 1. Members; 2. Honorary Members; 3. Senior Members; 4. Associates; 5. Junior Members; 6. Rocky Mountain Members. All shall be equally entitled to the privileges of membership, excepting that no member of any class whom residence shall be outside of the United States of America, except those residing in Mexico and Canada, shall be entitled to vote. SEC. 2. Members: A person to be eligible for election or transfer into the claw of Member must be at least 27 years of age and must have had at least six years' employment in the practice of engineering, mining, geology, metallurgy, or chemistry, during at least three years of which he must have held positions of responsibility in one or more of these fields. This shall not apply to Rocky Mountain members.

Jan 1, 1936

Wyoming State Geological Survey, Capitol bldg , Cheyenne, Wyoming. John G Marzel, State Geologist. Unfortunately, most of the publications of the Wyoming State Geological Survey are now out of print In particular should be mentioned Bulletins describing the various oil fields of Wyoming, and Bulletin 17, Bibliography and index (1918), all of which are out of print State geologic and topographic maps are also not available. A list of publications will be sent upon request Still available are: Bulletin 18, Mining laws, state and federal (1921), 19, Mineral hot springs of Wyoming (1926), 20, Atlantic City-South Pass gold mining district (1926), Circular 5, Operating regulations to govern the production of oil and gas on state and patented lands (1929). The last two Biennial Reports, issued 1928 and 1930, are still available. The bulletins and reports listed are distributed free.

Jan 1, 1933

BULLETIN 177. The decline and ultimate production of oil wells with notes on the valuation of oil properties, by C. H.- Beal. 1919. 84 pp., 4pls., 80 figs. BULLETIN 179. Abstracts of current decisions on mines and mining, reported from September to December, 1918, by J. W. Thompson. 1919. 166 pp. TECHNICAL PAPER 214. Motor gasoline; properties, laboratory methods of testing, and practical specifications, by E. W. Dean. 1919. 33 pp., 2 figs. TECHNICAL PAPER 219. Combustion and flue-gas analysis, by U. S. Fuel Administration. 1919. 12 pp., 5 figs. TECHNICAL PAPER 223. Cost-keeping for small metal mines, by J. C. Pickering. 1919. 46 pp. Only a limited supply of these publications is available for free distribution. Publications should be ordered by number and title. Applications should be addressed to the Director of the Bureau of Mines, Washington, D. C.

Jan 7, 1919

Recognizing the fact that the problems of the committee named by the Board to prepare the "official ticket" for officers and Directors of the Institute are various and difficult; and desiring to assist this committee by setting forth some of the principles that should guide the committee and some of the qualifications that should be required of candidates, the following instructions are formulated and the Secretary is directed to publish them in MINING AND METALLURGY concurrently with the publication of the names of each newly appointed Nominating Committee and to send a copy to each member of the Committee. Each year the Nominating Committee is to select "official" candidates for eight places, as follows:, (1) President and Director (2) Vice-President and Director (3) Vice-President and Director (4) Director (5) Director (6) Director (7) Director (8) Director

Jan 1, 1939

Feb. 5, 1917. To the President, Executive Mansion, Washington, D. C. We, the presidents of the national societies of Civil, Mining, Mechanical and Electrical Engineers and of the United Engineering Society, with a membership of thirty thousand, cordially unite in supporting Congress and the Administration in its stand for freedom and safety on the seas, and we are confident that we represent the membership of the four societies in offering to assist toward the organization of engineers for service to our Country in case of war. GEORGE H. PEGRAM, President of the American Society of Civil Engineers. L. D. RICKETTS, President of the American Institute of Mining Engineers. IRA N. HOLLIS, President of the American Society of Mechanical Engineers. H. W. BUCK, President of the American Institute of Electrical Engineers. CHARLES F. RAND, President of the United Engineering Society.

Jan 3, 1917

By L. D. Mullins, H. B. Bradley

Numerous articles have appeared in the literature citing the application of the potentiometric analyzer to cycling operations. Specific information obtainable by a potentiometric analysis, as noted by various investigators, includes: 1. Pattern sweep efficiency for various injection and production rate programs. 2. Injected fluid breakthrough time at production wells. 3. Optimum production and injection rates. 4. Prediction of injection and/or production well locations. 5. History of advance of the in-jected-produced fluid interface. 6. Ultimate life of the reservoir. 7. Ultimate reservoir production. This note describes a procedure for predicting pressure distribution in a gas-condensate reservoir by using the potentiometric analyzer to obtain potential distribution data on an analog model of the reservoir and then applying Muskat's' equations. The method relates the volumetric weighted average datum pressure to the mean potential in the model.

Jan 1, 1958

Dues: Arrears........................................... $ 4.878.18 Current........................................... 96.174.46 New Members..................................... 6.281.50 Dues for future periods received in advance........... 1.745.28 $109.079.42 Initiation Fees.................................................. 7,879.00 Magazine Receipts: Advertising Gross Receipts.......................... $39,247.77 Magazine Sales.................................... 3,820.04 43.067.81 Sale of Transactions Volumes 75 and 76............; .... $ 2,525.93 Sale of Transactions and Special Editions............... 7,586.00 Sale of Year Book.................................... 141.60 Sale of Authors' Reprints............................. 2,032.97 Sale of Pamphlets.................................... 1,346.29 Sale of Bindings...................................... 4,551.90 18,184.69 Interest Received: On Bank Balance and Temporary Investments......... $ 2,780.75 On Life Membership Fund.......................... 2,106.43 On James Douglas Library Fund..................... 5,399.45 On General Reserve Fund........................... 1,995.33 12.381.96 Miscellaneous Receipts........................................... 131.16 Total Receipts................................................ $190,624.04

Jan 1, 1929

1. Healthy and active Local Section or¬ganizations are vital factors in promoting the vigor and growth of the Institute. 2. Activity on the part of Local Sections should be recognized and stimulated by appropriation of funds from the Insti¬tute's treasury; and these appropriations should be as large as is consistent with the relative needs for other activities. 3. As between different Sections, the amount of such appropriations should be based primarily on the extent of activities as reflected in the number and character of meetings held and the attendance of the members at such meetings. 4. In making a request for funds for any year, the officers of a Local Section should submit a report on the printed form approved by the Directors at their meeting on November 19, 1937. 5. A standing Committee on Local Sec-

Jan 1, 1944

The first practical and successful use of a laser-beam guidance system for a tunnel machine drilling to a remote target has been achieved at the Bureau of Reclamation's Navajo Indian Irrigation Project near Farmington, N. Mex. Using such a guidance system, the Hughes Tool Co.'s "Betti I" drilled a 10,000-ft long tunnel in eight months and 18 days to within 5/8-in, of established line and grade. The electronic system which guided the "Betti I" features a gas laser whose beam is aimed at two light-sensitive targets on the boring machine. From these targets, the operator of the machine receives electric signals on a read-out panel which tell him the machine's precise location within the tunnel. The operator can then make any adjustments necessary to maintain line and grade while drilling ahead.

Jan 6, 1966

By Robert W. Edwards

The Morris mine, operated by the Inland Steel Co., is located about 5 miles west of Ishpeming, Mich., near the west end of the Marquette Range. The ore, a soft hematite, is mined by sublevel caving and stoping. A considerable amount of surface water flows down through the cave into the ore or percolates down along footwall dikes in the iron formation. Because of this water, the broken ore cannot be stored in the raises and must be scraped from the sub directly into the tram cars. Efficient tramming, therefore, requires close coordination between the scraping and loading operations. In the past this has been hampered by the lack of a suitable means of communication between the mining contracts and the drawpoints on the tramming levels. Among the devices that have been tried unsuccessfully are flashing lights, air whistles, and electric buzzers.

Nov 1, 1955

TULSA, the host of the Petroleum Division this year, is the oil metropolis of the Mid- Continent and gateway of the Southwest. It has risen in less than three decades from a dusty cattle town of less than 1000 population to its present-day status of a modern, wide-awake and prosperous city of close to 150,000, with an assessed realty valuation of approximately $100,000,000. Oil was discovered near Tulsa in 1901, and with it came th.2 development of the Mid-Continent field, one of the richest in the world. Tulsa from the start has been the center of operations, and its location on foul- and aggressive application of the airplane to oil-field requirements tends to fix this status as production is developed farther and farther afield. That Tulsa is far more than an ephemeral oil town is punched into the newcomer's- especially the Easterner's-mind, as he is whisked by taxi from the railroad station to the Hotel Mayo. The cicadalike pounding of the riveters on the steel skeletons of many skyscrapers, mounting upward to fill the gaps in an already well-developed skyline, dispels the feeling of a new atmosphere and puts him back on Forty-second Street, Michigan Boulevard or whatever his own particular "Main Street" may be along which an American city is being remade. Practically every company of any importance operating in the Mid-Con-

Jan 1, 1928

By C. A. Stickels

A heat of electrolytic iron, to whzch alunzinutn and nitrogen had been added, was hot-rolled, cold-rolled 90 pct, and recrystallized at temperatures from 500" to 700°C. Primary recrystallization textures appear to arise from competitive growth of two types of nuclei: 1) those having orientations belonging to the "usual" primary recrystallization texture found in riming steel, and 2) those with the {111} (110) ovientation. Development of a (111}(1 10) component in the primary recrystallization texture occurs only over a certain interval of isothermal recrystallizatzon temperatures when the material is supersaturated with respect to the precipitation of AlN. Lowering the degree of supersaturation depresses the temperature interval in which a (111)(110) component occurs. An elongated, 'pancake-shaped" recrystallized pain structure and a marked delay in the start of recrystallization were found in all specimens which were supersaturated with respect to A1N precipitation after cold work, regardless of their recrystallization texture. ONE of the consequences of killing low-carbon steel with aluminum is a significant change in recrystallization behavior. About 15 years ago, Solter and eatttiel showed that this behavior was largely controlled by aluminum and nitrogen in the steel. If complete precipitation of A1N was prevented before cold rolling, an increased "recrystallization temperature" was observed in subsequent. annealing, and the recrystal-lized grains were not equiaxed. Leslie et a1.2 studied this phenomenon in some detail and clearly demonstrated the relationship between A1N precipitation, recrystallization kinetics, and the development of "pancake-shaped" grains. It has also been known for some time that aluminum-killed steels, processed to produce elongated "pancake" grains, develop a (11 I}( 110) primary recrystallization texture. This texture has not been found in iron or low-carbon rimming steel as a primary texture4j5 but has been observed following grain growth in electrolytic iron.5 The present work was undertaken to study in more detail the effect of A1N supersaturation on recrystallization textures in iron. LITERATURE REVIEW The deformation texture in heavily rolled iron has been studied in detail by Bennewitz.~ The texture consists primarily of a partial fiber texture about a (110) axis in the rolling direction, designated here as fiber texture A. It includes the range of orienta- tions (111)[110] - (001)[ 110] - (11l)[110]. A weak secondary texture also is present.6 This is a duplex partial fiber texture about two (110) fiber axes located 60 deg from the rolling direction and 30 deg from the sheet normal. The range of this texture, designated here as fiber texture B, about the [101} fiber axis is (112)[110] - near (545)[252] - (211:1[011] *The range given here follows Bennewit~.~ A few pole figures from re-crystallized material indicate a broader range than this.' However, the components which are strongest in the recrystallization texture are in this range.'________________________________________________________ Primary recrystallization textures in unkilled steels can be accounted for by growth of members of fiber texture B present in the deformed metal.5 However, while members of fiber texture B dominate the primary texture, other orientations survive primary recrystallization as well. In particular, some {111}(110) members of fiber texture A must also grow during primary recrystallization, because a well-defined {1ll)( 110) texture develops during subsequent grain growth at 700°C.5 The unusual recrystallization behavior of deformed supersaturated solid solutions has been attributed to: 1) retention of the solute in solution,' 2) formation of coherent, preprecipitation solute clusters prior to and during re~r~stallization,~ and 3) formation of a precipitate prior to and concurrent with recrystallization.'~-'~ When aluminum is supersaturated with iron, the difference in grain boundary mobility between general high-angle boundaries and certain special coincidence site boundaries is apparently eliminated.' In aluminum-killed steels, precipitation of A1N can take place at ordinary subcritical recrystallization temperatures. The rate of precipitation increases with increasing aluminum or nitrogen contents.2'13 There is some doubt, however, as to whether true precipitates form during the time at temperature needed to complete recrystallization. Leslie ef a1.2 found that precipitation in one steel was complete after about 100 min at 700GC, or after about 1000 min at 650GC, as measured by chemical analysis for AlN. Aoki et a1.,13 using internal friction for dissolved nitrogen, showed that a large fraction of the dissolved nitrogen was removed from solution within a few minutes annealing time at temperatures from 400" to 800°C. However , the rate of formation of AlN, as detected bv chemical analvsis. was much slower than the apparent rate of nitrogen removal. Hasebe,'~~ using carbon extraction replicas, has identified A1N precipitates by electron diffraction in a 0.2 C steel, solution-treated at 1300°C and annealed 2 hr at 700°C. Borchers and kim,I6 also using a replication technique, observed precipitates after annealing treatments as short as 2 min at 640°C. However, Leslie et a1.' state that no A1N precipitate can be seen while recrystallization is being inhibited in aluminum-killed steel.

Jan 1, 1967