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By Milton F. Goodrich

The idea of using water-only cyclones to scalp clean coal from the feed to other devices has recently been gaining in popularity.l,2,6 An indication of this popularity is that water- only cyclone scalping is already employed in a few commercial plants. Water-only cyclones scalp the feed to a heavy media vessel in the Warwick plant,3 to Deister tables in the Rowland plant,4 and to a heavy media cyclone circuit in the Amherst Coal Company's McGregor plant.5 Despite this trend, we found surprisingly little information in the literature on the performance of water-only cyclone scalping. Therefore, we undertook a study of its technical merits, limiting our investigation to a water-only cyclone scalper in conjunction with heavy-media cyclones. We felt this to be a reasonable combination of equipment, since both processes operate well on the same size coal. First, we developed simple mathematical relationships revealing general characteristics of the system. Next, we compared the clean coal yield and quality obtainable by the system on four different coals with that obtainable by heavy-media cyclone circuit alone and water-only cyclones middlings recirculation circuit alone. This was done by using computer program to simulate the operation of the three systems. Finally, we considered the effect that implementation of the system would have on a typical preparation plant circuit.

Jan 10, 1978

By Lawrence K. Nordell

This paper reviews practices used In the selection and sizing of belt conveyors and stacker systems commonly used in crushing and grinding plant facilities. Historical and modern methods of sizing this equipment are presented. The new methods Include: 1) probability theory applications for establishing component reliability, 2) "Monte Carlo" simulation techniques used in evaluating alternative system designs and in establishing service factors and corresponding availability Indices of each system, 3) quantifying the system and component operating characteristics using computer assisted modeling tools simulating rigid body and elasto-mechanic behavior for starting and stopping large and/or complex belt conveyors.

Jan 1, 1982

By Roger L. Beals, George A. Tweedy

The results of the cyanide-operations, given in detail in the following paper, show the progress that is being made at the Minas del Tajo. The old pan-amalgamation process, in operation up to and including 1905, while paying a profit on high-grade ores, was no longer able to treat profitably the ores in sight at that time; hence an alteration in the process was imperative. The success of this alteration is eloquently expressed by the following data : Pan-Amalgamation. Cyanidation. 1905. 1905. " 1908. Tons treated,.... 51,387 58,983 69,200 Value per ton (U. S. currency),. $ 10.78 $8.39 $8.28 Extraction, per cent.,.. 65.00 88.56 87.45 Extraction, per ton,.. $7.00 $7.43 $7.24 Total cost, per ton treated, . 6.50 4.36 4.01 Profit, per ton treated,.. 0.50 3.07 3.23

Jan 1, 1911

By A. C. Fieldner

COKE and by-products have prime importance in the war program. The past year was marked by the construction of new and the rehabilitation of old by-product and beehive ovens and by the increase of production from existing plants to practically 100 per cent capacity. W. T. Brown's paper, "Plan to Improve Blast-Furnace Coke," presented at the Fuels Conference in St. Louis, Sept. 30, showed how the blending of low- and high-volatile coal improved the physical properties of coke and that improvement of the quality and uniformity of coke favored an increase of blast-furnace capacity- a vital need in the war program. Others in the industry have likewise increased production of coke or recovery of by- products by various innovations or changes in operation. Recognition of the value of pooling these developments for the benefit of the entire industry led to organization of a survey of coke- oven plants and blast furnaces by the Bureau of Mines in co-operation with the Solid Fuels Co-ordinator with a view to improving metallurgical coke production and recovery of by-products. This survey is being conducted with the help of an advisory committee consisting of representatives of the Bureau of Mines, the Solid Fuels Co-ordinator, the War Production Board, and the blast-furnace, coke-oven, and coal-mining industries.

Jan 1, 1943

By W. C. Bleimeister

The rock salt deposits of the U. S. occur in five major basins: 1) the Eastern Basin (which includes parts of Michigan, Ohio, Pennsylvania, New York, West Virginia, and Ontario) ; 2) the Gulf Coast Basin (the northern rim of which includes parts of Alabama, Mississippi, Louisiana, Arkansas, and Texas, while its southern rim includes parts of the Isthmus of Tehuampetic and the Yucatan Peninsula of Mexico), 3) the Southwestern Salt Basin (which includes parts of Kansas, Colorado, Oklahoma, Texas, and New Mexico), 4) the Williston Basin (which under- lies parts of North Dakota, South Dakota, Montana, and Saskatchewan), and 5) the Green River Basin (whose periphery underlies parts of Wyoming, Utah, and Colorado). The greatest salt production in the U. S. is obtained from the Eastern Basin,-particularly from the areas of Michigan, Ohio, and Ontario. In 1958 the salt production from these areas amounted to 8.7 million tons or 35.3 pct of the combined total produced in the U. S. and Canada. Of the 24,286,000 tons produced by Canada and the United States, 6,443,000 tons were in the form of rock salt from dry mining, while 17,843,000 tons were produced from wells in the form of artificial brine, the result of dissolving the rock salt formation by fresh water. Three important factors lie behind the location and development of this salt mining area:

Jan 5, 1961

By Guy N. Bjorge

HOMESTAKE'S mining methods today are of necessity controlled to a considerable extent by that which has been done in the past. This may be shown by the fact that our two main operating shafts now, the B. & M. and Ellison, were begun in 1878 and 1896 respectively, so that-the loca-tions of shafts, locations of all the drifts on the upper levels, and a great deal of sloping was done before any of us now connected with the mine had anything to do- with it. Anything that I may say is not to be construed as criticism of those who have gone before for it would be a sad commentary indeed on us if we had not learned something from their experience. The levels down to the 1100 in the Homestake mine are spaced at 100-ft. intervals, and below that at 150-ft. intervals. The general plan of develop-

Jan 1, 1934

By I. H. Van Horn

IN the development of the incandescent electric lamp one aim of the investigators has been to establish the fundamentals of lamp design, so that the performance of any new lamp may be accurately predicted. The study of the temperature relations in lamps has done much toward establishing these fundamentals. Fig. 1 gives the typical FIG. 1.-ARRANGEMENT OF PARTS IN MAZDA B AND MAZDA C LAMPS. arrangement of the lamp parts in both the Mazda B (vacuum) and Mazda C (gas-filled) lamps. The outstanding differences are the filament form and the bulb shape. The ideal lamp is one in which the filament operates at a uniform temperature throughout its length. In practice, it is necessary to disturb this uniformity by the introduction of supports and terminals. The amount of cooling at the supports and terminals affects the over-all efficiency of the filament as a light producer. The life of the lamp is ordinarily proportional to the maximum and not to the average filament temperature. The Holborn-Kurlbaum type of optical pyrometer has

Jan 9, 1919

PRESIDENT AND DIRECTOR DONALD B. GILLIES CLEVELAND, OHIO PAST PRESIDENTS AND DIRECTORS R. C. ALLEN CLEVELAND, OHIO D. C. TACKLING SAN FRANCISCO, CALIF. TREASURER AND DIRECTOR KARL EILERS NEW YORK, N. Y. VICE-PRESIDENTS AND DIRECTORS H. G. MOULTON NEW YORK, N. Y. HARVEY S. MUDD Los ANGELES, CALIF. PAUL -D. MERICA NEW YORK, N. Y. WILFRED SYKES CHICAGO, ILL. WILLIAM B. HEROY HOUSTON, TEXAS HENRY KRUMB NEW YORK, N. Y.

Jan 1, 1939

By T. Sekimoto, T. Kokubo, M. Yamamoto, K. Masuda, T. Moro, H. Sakamoto

The choking-free cyclone was developed primarily to remove solid particles suspended in a slurry containing fibrous materials, such as municipal solid waste. This cyclone is characterized by a screw conveyor at the underflow side of the cyclone. The screw conveyor has a hollow rotational shaft for air supply and is driven by a variable speed motor for discharge control. Even if the underflow discharge is highly concentrated, this type of cyclone can be stably operated without nozzle choking. High classification efficiency similar to that of a conventional cyclone can be obtained as a result of air introduction through the hollow rotational shaft. The recovery of organic matter and the removal efficiency of inorganic matter were actually improved by the application of this cyclone to municipal solid waste. After applying this cyclone to the desliming of fine sand, sand product of low water content was recovered.

Jan 1, 1980

By R. W. Bowers

In order to hoist the ore according to grades, stope samples are taken. Three equidistant grooves are picked across the breast at right angles to the dip of the ore, the part removed being caught in the hand and then put into a small bag. When there is broken ore in the breast, the lines are continued down the pile and a small amount taken at intervals of the length of the sampler's pick handle. The quantity of sample from each breast will be between 2 and 3 Ib. If there are two grades of ore, bessemer and non-bessemer, there are two sets of brass checks for each chute, each check stamped with the number of the chute; one set of checks has the word "bessemer" and the other "non-bessemer." Before any ore is removed from the chutes, it is the duty of one man to see that the proper set of checks is at each chute in the mine. As each motor car is loaded, a check is attached to it. When the train reaches the shaft, the sample man removes the check on the first car, notes the grade, and directs the motorman to spot it over the proper pocket. The check is then hung on a hook with the number corresponding to the chute from which the ore came. The sample man throws a short rope with a knot in the end over the car and at the point where the knot falls a standard scoopful is taken. This is placed in a large bag that hangs directly under the hook containing the checks for that particular chute. These chute samples represent a check on the grading of the various contracts and by counting the tags a check is obtained on the miner's tally of the ore going into each chute; the total of the checks represents the hoist. During the stocking season, a standard scoopful is taken from each top tram car. This sample is taken in the same way as the chute samples at the plats underground. Top-of-car Samples These samples are taken by using a rope, preferably a clothesline, knotted each 18 in. of its length, and a hammer and a scoop. The standard scoop measures 31/2 by 21/4 by 11/4 in. and holds about 1/2 Ib. of ore. The rope, as applied to the usual railroad cars at the mine, is knotted into fifteen sections. It is placed diagonally over the car from

Jan 1, 1925

By H. N. Lawrie

Introduction. THIS study was undertaken on account of the lack of definite knowledge concerning the influence of bismuth on wire-bar copper, and the small elimination of bismuth from copper-matte during the smelting-operations. The early workers who studied the influence of bismuth on copper confined their investigations to malleability and ductility-two physical properties which are related to the others so intimately that their determination is of primary importance. Karsten ' and Levol,2 using bending- and mealleability-tests, seem to have been the first to take up the subject, and while their results are incomplete, they agree in the main with the later work of Hampe.3 The bending-tests used by the first investigators consisted in bending the specimen until it failed. The malleabilitytests were made by beating the material to a knife-edge with a hammer. Hampe not only determined the percentage of bismuth which would cause red-shortness and cold-shortness of the alloy, together with other influences of bismuth on the malleability and ductility of copper, but also took up the influence of the bismuth protoxide, BiO, on copper, and of bismuth sesquioxide, Bi2O3, on the copper protoxide, CuO. Hampe's conclusions of the influences of these two latter compounds of bismuth on copper are as follows "If the protoxide of bismuth be alloyed with metallic copper, it is not changed to metallic bismuth, but remains mechanically distributed throughout the copper.

Sep 1, 1909

By Robert T. Chapman

The revolution in equipment for blasthole drilling, ore loading, and ore hauling has been so rapid over the last ten years that it has generated an important new profit potential in the mining industry. With the new high-capacity machinery now available, it is possible for a mining enterprise to earn a profit from larger and lower grade orebodies than ever before despite the ever-increasing burden of rising costs. Just what such equipment can accomplish when coupled with improved mining practice has been demonstrated with startling success at the No. 1 mine of Minerva Oil Co. near Cave-in-Rock in Hardin County, Ill. The No. 1 is an underground operation which has been producing fluorspar and zinc ores and concentrates continuously since 1944. A few years ago, when the mine neared the familiar cross-roads where rising costs, increasing tonnages, and relatively static product prices converge, company officials decided to bolster the operation with new mobile equipment. They chose three machines which proved so effective that output at the No. 1 doubled between 1963 and 1965,while costs dropped by about 40% in the same period.

Jan 11, 1966

By E. Ray Webb

A interest to geologists and to mining and petroleum engineers is a laboratory method for determining the dip and strike of sub- surface structures, as well as the direction of fault planes traversing them. The information is derived by making use of the magnetic properties of borehole cores which must show visible representations of bedding or fault planes. Complete knowledge of these factors aids greatly in the successful exploitation of both ore and petroleum deposits.

Jan 1, 1940

By H. Hubert

THE first attempts at direct utilization of blast-furnace gas in engines were made in 1895. For a considerable time the gas had been burnt in Cowper stoves for heating the blast for the furnace, and under the boilers which supplied steam to the blowing-engines, and others serving the furnaces. It was natural, therefore, that the idea of directly employing it in gas-engines should have occurred simultaneously to several engineers, notably to Lürmann and to Lencauchez, who had pointed out the blast-furnace as a powerful -gas-producer. Nevertheless, nowhere had any attempt been made to apply it to this purpose up to the end of 1894, when Thwaite proposed it to Mr. James Riley, of the Glasgow Iron & Steel Company. About the same time investigations were being made in Belgium and in Germany, independently of Thwaite's experiments, which were not generally known on the Continent. The industrial world, which up to that time had hardly favored the idea, had thus been gradually prepared to receive it. The gas-engine, long restricted to small sizes and dependent upon the use of an expensive fuel obtainable only in large centers, now began to make headway. At the Paris Exhibition of 1889 two engines of 100 h.p. were shown and excited much interest among engineers. One had four cylinders, and was made at the celebrated works of the Deutz Company, and the other was a single-cylinder engine, exhibited by two French designers, Messrs. Delamare-Deboutteville and Malandin. In the meanwhile the design of gas-producers had made important progress, completely freeing the new engine from its

Nov 1, 1906

By George Otis Smith

WHAT American can enter this Western empire without his imagination being stirred by the stories of its past-yes, and even more by visions of its future! Whether we travel by rail or by auto, our pathway has its traditions of exploration and its records of early settlement. The mountain passes and the routes used by today's commerce are lasting memorials of the pathfinders whose unconquerable purpose was to search out a way-Lewis and Clark, Bonneville, Pike, Long, FrBmont, their names still live in your rivers and lakes and peaks. It was the glory of these adventurers that they spied out the land so that others might follow that long pro- cession of pioneers who occupied the new country- fur traders, gold miners, cattlemen, and homesteaders. Each of these pioneers attacked the problem of transportation in his own way, and each sought by his own method to win the resources whose richness had been reported by the pen of the Government explorer or by the swift rumor of the unnamed and unfamed adventurer. Trails were worn deep by these home or fortune seekers as they passed through the mountain barriers in successive waves-and these were waves that did not ebb, for this was an army of occupation. Along these main pathways of the West, as one historian has pointed out, the figure of chief interest was the sad- faced woman sitting on the front of the covered wagon.

Jan 1, 1926

By Frederic Benard

PRIOR to 1936, the Ontario Refining Co. received all incoming blister copper from The International Nickel Company's smelter in the usual form of 460-lb. cakes, or slabs. These were received in open cars in lots of 250 pieces. At the refinery the cakes were unloaded onto narrow-gauge cars, for convenient handling and pickup by charging cranes. In March 1936, an investigation was started on the feasibility of transferring converter copper in the molten state from the smelter to the refinery anode furnaces, a distance of 1 ¼ miles. Although common in steel practice, the transportation of blister copper in this form had not previously been attempted and a preliminary study of the various factors involved was therefore necessary. For this purpose, a series of experiments was made in which molten copper, removed at different stages during the furnace cycle, was held in a small portable holding furnace. This vessel was essentially a refractory-lined steel cylinder provided with ports for filling and emptying, heated by an oil burner. Dimensions of the steel shell were 3 ft. 10 in. diameter by 7 ft. 3 in. long, and thickness of refractories depended on the design and combination used for the particular experiment. The vessel was filled with approximately 2 ½ tons of copper at a predetermined temperature, the lining having been preheated to a definite point by means of an oil burner. All openings were well luted and temperature readings were made every 15 min. by means of an immersion-type thermocouple. In this manner the rate of heat loss resulting with different refractory design could be developed. The ratio of exterior surface to weight of metal was taken into consideration in comparing the experimental results with what might be expected for a full-sized unit, and observations were also made on type and degree of slag accretion. It was not possible to get as much information on this latter point as desirable, but all evidence showed that the problem would be control of slag build-up rather than attack on refractories. From the information derived, and in consultation with the engineering staff of the supplying company, an order was placed for the first

Jan 1, 1938

By S. Kado, G. Derge, L. Yang

Self-diffusion coefficients of silver in molten silver have been measured by means of the capillary-reservoir method in the temperature range 1002" to 1105°C. The results can be .represented by the equation D = (7.10 i 0.06) X 10-4 exp [(—8150 ± 1130)/RT]. The heat of activation agrees within the limit of experimental uncertainty with that for the viscous flow. The validity of the Eyring and the Stokes-Einstein equations are examined on the basis of the self-diffusion coefficients obtained and the known viscosity data of molten silver. MEASUREMENT of the self-diffusion coefficient of silver in molten silver was made in the temperature range 1275° to 1378°K, using the capillary-reservoir method and &"' as the radioactive tracer. The experimental arrangement is shown in Fig. 1. Silver of 99.99 pct purity (fine silver), was melted and degassed in vacuum in a graphite crucible situated inside a McDanel vacuum jacket. The crucible (4 in. tall and 1 in. ID) was protected both at the top and at the bottom with graphite shields and contained about 220 g of silver. The sample holder was a piece of graphite rod (1 in. long and 1/2 in. diam) with 4 capillaries drilled longitudinally into it. The holder was screwed onto a long graphite rod (12 in. long and 74 in. diam) which was connected to a steel disk hanging on a nylon string through a glass pulley. The steel disk kept the sample holder at the center of the McDanel tube and was heavy enough to overcome the buoyancy when the holder was lowered into the molten silver. By turning a handle connected to the pulley through a tapered glass joint, it was possible to raise or lower the sample holder without breaking the vacuum. Two such arrangements were constructed, sitting side by side in 2 Kanthal furnaces. One with non-radioactive silver in its crucible was used for the diffusion run and the other with radioactive silver in its crucible was used for filling the capillaries. To fill the capillaries with radioactive silver, the sample holder was degassed first and then lowered into the radioactive molten silver in vacuum. Purified argon gas was then admitted into the system to push the liquid silver into the capillaries. After cooling in argon, the filled capillaries were polished on emery paper to expose the top of the rod and used immediately as samples for the diffusion run which was carried out at the same temperature as that used for filling the capillaries. During the diffusion run, the samples were degassed in vacuum and lowered slowly into the nonradioactive molten silver before purified argon was admitted into the system. After a predetermined period of time, the samples were raised out of the melt and cooled in argon. The temperature of the melt was measured before and after the run with a chromel-alumel thermocouple inside a McDanel protection tube. Another chromel-alumel thermocouple attached to the outside wall of the McDanel vacuum jacket was used to indicate any fluctuation in the temperature of the furnace during the run, which was found to be less than ± 2°C for the longest run made (93 min). The temperature gradient inside the molten silver was found to be negligible. No significant difference was observed in the results obtained whether the melt was stagnant during the run or was stirred by raising and lowering the sample holder slowly a few times a minute for a distance of about 1/4 in. inside the melt.

Jan 1, 1959

YEAR or ELECTION 1913. FRANK DAWSON ADAMS Montreal, Canada. 1933. KARL EILERS New York, N. Y. 1922. FEDERICO GIOLITTI Q. Torino,Italy. 1906. SIR ROBERT A. HADFIELD London, England. 1921. FRANK WILLIAM HARBORD London, England. 1917. HERBERT HOOVER New York, N. Y. 1931. WALDEMAR LINDGREN Cambridge, Mass. 1921. C. MCDERMID London, England. 1913. EZEQUIEL ORDOAEZ Mexico City, Mexico 1935. ROBERT PEELE New York, N. Y. 1938. A. M. PORTEVIN Paris, France. 1937. Joan V. W. REYNDERS New York, N. Y. 1937. GEORGE S. RICE Washington, D. C. 1911. ROBERT H. RICHARDS Cambridge, Mass. 1934. T. A. RICKARD Victoria, B.C., Canada. 1933 Cambridge, Mass.

Jan 1, 1938

By F. C. Smyers, E. W. Merrick

ALTHOUGH the zinc and pyrite concentrates produced at Midvale go to other companies, the United States Smelting Refining and Mining Company smelts and refines its own lead. Refining is the first step of the process that is done at some distance from the mining operations, the plant being at East Chicago, Ind., an industrial center about 25 miles southeast of Chicago. For years it has been notable as being the only lead refinery in the country using the Betts electrolytic process. The original buildings, many of which are still in use, were erected in 1906 when the plant was known as the United States Metals Refining Co. In 1920 the parent company sold its copper refinery at Chrome, N. J., and since the copper refinery was also known as the U. S.

Jan 1, 1948

YEAR OF ELECTION 1913. FRANK DAWSON ADAMS, Montreal, Canada. 1933. KARL EIKERS New York, N. Y. 1922. FEDERICO GIOLITTI Torino, Italy. 1906. SIR ROBERT A. HADFIELD London, England. 1921. FRANK WILLIAM HARBORD London, England. 1917. HERBERT HOOVER Washington, D. C. 1941. DANIEL COWAN JACKLING San Francisco, Calif. 1939. HENRY KRUMB New York, N. Y. 1921. C. McDERMID London, England. 1913. EZEQUIEL ORDONEZ Mexico City, Mexico. 1935. ROBERT PEELE New York, N. Y. 1938. A.M. PORTEVIN Paris France 1937. JOHN V.W. REYNDERS, New York, N. Y. 1937. GEORGE S. RICE Washington, D. C. 1911. ROBERT H. RICHARDS Cambridge, Mass. 1934. T.A. RICKARD Victoria, B.C., Canada

Jan 1, 1941