Search Documents

* A demonstration pipeline for transporting coal will be constructed by Pittsburgh Consolidation Coal Co, at the Georgetown strip-mining operation near Cadiz, Ohio, The 12-in., 17,000-ft line, special crushing and preparation equipment, and pumps especially designed for the operation will cost about $550,000. A slurry of fine coal and water will be fed into the line and moved through it under pressure. * Sulphur resources in the U.S. are being rapidly exhausted with no new major deposits being found, This common mineral may become one of the most strategic items during the next five years. Recovery of sulphur from pyrites is being considered in case of an emergency. Already the British have adopted stringent measures to conserve sulphur supplies.

Jan 3, 1951

By Ernest R. Dickie

IN 1945 the Bagdad Copper Corp. decided to change from block caving to open-pit mining. By early 1948 the conversion was completed and production was increased from 1500 tons per day to 4000 tons per day. Open-pit mining costs decreased approximately 40 pet from the cost of producing ore by the underground method. At present one P & H model 1400 all-electric 4 1/2-yd shovel and one P & H model 1055 Diesel 3-yd shovel are used continuously for stripping. One 21/2yd North- west shovel handles the ore. Delivery of a new P & H 1055 electric shovel for stripping is expected this month. Blasthole drilling is performed with two Bucyrus model 22 and two Bucyrus model 27 churn drills.

Jan 9, 1951

By John L. Walte

Consolidation Coal Co.'s Renton mine, a 680 000-t/y (750,000-stpy) underground operation located in western Pennsylvania, has reduced the time required for overcast construction in its advancing operations by adopting a prebolting technique followed by multiple blasting. In the past, the mine's overcasts had been excavated by the continuous mining machines used to advance the section. More recently, the overcasts were blasted down and then rebolted with a stoper drill. The new system, using a two-part combination bolt, has proven very successful in speeding up overall construction time and providing more positive horizontal control in blasting. The prebolting approach allows the roof to be blasted down and loaded out without the need for rebolting the shot-out area.

Jan 6, 1978

No. 349.-A Canadian university wishes to engage a man to teach non-ferrous metallurgy and ore-dressing as well as to direct research work. The instruction work covers 7 months but the research work is continued throughout the year. To a suitable man the rank of professor will be granted. Applicants are requested to state education, experience, salary desired and any other particulars that might assist in selecting a man for this position. No. 354.-Wanted, for Northern Nigeria, one chief and two assistant mining engineers, competent surveyors, with good knowledge of alluvial tin mining and dressing of tin concentrate. Preferably with previous Nigerian experience, and exempted or able to. secure passport. Apply in writing, stating qualifications, experience and salary required.

Jan 12, 1918

PLANS for development of the San Manuel ore- body have been worked out and are progressing parallel with construction of the surface plant. This property lies in the Old Hat mining district, Pinal County, Ariz., about a mile south of Tiger where the St. Anthony mine once produced gold, molybdenum, vanadidn, lead, and zinc. Two development shafts have been completed and serve as ingress for preparation of the 1475 haulage level and 1415 grizzly level. Three other shafts are being put down. The Nos. 3A and 3B shafts will provide the ore hoisting facilities. The No. 4 shaft, now being sunk, will be at the main mine service and supply yard, with primary function to provide the mine with supplies.

Jan 7, 1954

THE illustration below shows the design of the face of the clock to be erected as a memorial to the American engineers who gave their lives overseas in the World War. It will be placed in the tower of the library at Louvain, which has been rebuilt through contributions from America. Large clocks seldom have figures on their faces, and each hour on this one will be marked by a gold star, the four faces containing 48 stars, one for each State of the Union. Contributions toward the memorial have been received from every one of the States, and from Alaska and Hawaii as well, but additional subscriptions are invited by the Com-mittee which is arranging for the memorial.

Jan 3, 1928

Phase II of President Nixon's economic game plan will incorporate many top flight metals mining companies. The large corporations must receive approval from the Cost of Living Council before increasing prices and or wages. The theory here is that, with large companies complying with advance approval, smaller firms will be examined more closely by government, and thus will be forced also to comply. Rep. Paul McCloskey (R.-Calif.) called for a moratorium on strip mining for "the few years involved before we adopt a national energy policy and a national land use policy." McCloskey, who is a cosponsor of Congressional legislation that would outlaw strip mining, told a hearing that a "moratorium can scarcely hurt us until national energy and land use policies are adopted."

Jan 1, 1971

By Martin J. Gungl, J. Lyman MacInnis

None of the industry submissions could persuade the Canadian Tax Reform draftsmen that the rate of return has had as much bearing on investors' decisions to invest in Canada as the success records of Canadian ore findings. The goverment opted for the position that mining capital goes where the ore can be found. Many tax incentives which were available until the end of 1971 have been greatly reduced. However, it is still recognized that new ventures in exploration and development of natural resources deserve a break even if there is reduced recognition of the established and highly successful members of the industry unless they continue to search and develop. The latter will also get some breaks for processing beyond the prime metal stage.

Jan 7, 1972

By Edel Moldenke

BURMA has long been known for its ruby, tungsten, and tin deposits, and, lately, for having the largest lead-zinc mine in the world, the Bawdwin Mine of the Burma Corpn. All the coal used, however, is imported from Calcutta; this is a bituminous coal of about 11,000 B.t.u., 24 per FIG. 1.-MAP SHOWING LOCATION OF COAL FIELDS AND TRANSPORTATION ROUTES. cent. ash, and costs about $8 per ton. Bituminous coal has not, thus far, been found, but many lignite deposits are known. The most promising lignite deposits are in the Namma field, Fig. 1, situated in the Northern Shan States of Upper Burma, about 30 mi. south of Lashio, the terminus of the Burma Railway, 750 mi. north of Rangoon. The

Jan 7, 1921

By I. Sheinhartz, H. M. McCullough

DURING the course of a lubrication study in relation to the compacting of metal powders, it became desirable to measure the thickness of sprayed graphite coatings on steel dies for hot pressing. The thickness of these lubricant coatings ranged between 0.0001 and 0.002 in. In their particular case, the authors were interested in a method for measuring the lubricant thickness on tapered die inserts having curved surfaces. The lubricant was sprayed on the inserts at an elevated temperature and it was desirable to measure the thickness as soon as possible after application. Various standard types of commercial equipment were tried. Most of the available devices operated on either a mechanical or magnetic principle. The mechanical devices, such as micrometers, dial indi-

Jan 1, 1956

By William E. Bruce

In recent investigation of drilling processes, the U.S. Bureau of Mines measured the operating characteristics of two percussive drills. Basically, this entailed measuring maximum piston velocities while drilling. The maximum piston velocity is not necessarily the same as the striking velocity. The latter is usually somewhat lower1 because most commonly used drills provide an air cushion which slows the piston just before it comes in contact with the drill rod. Penetration rates for the two drills were determined in nine rock types, and the physical properties of the same nine rocks were measured and tabulated. Then the penetration rates were plotted against the individual properties to determine the general relationships on which methods for predicting drilling rates could be based.2

Jan 1, 1970

By J. S. Orphanos

The requirements for controlling air and stream pollution are a most timely subject for concerned people. The coal industry has taken great measures to reduce pollution. With the use of more efficient scrubbing equipment on their thermal dryers, pollution has been considerably reduced. Furthermore, eliminating thermal drying completely by using centrifugal dryers (Bird screen bowls) to dewater fine coal products and meet consumer specification has completely eliminated air pollution. The coal industry is taking steps to eliminate stream pollution and the hazards created by tailings ponds. These plants are closing their water circuit by recovering all solids in solid-bowl centrifugal equipment. In doing this effectively and economically the water discharged into the streams does not contain any refuse solids. This provides a safe economical method.

Jan 1, 1976

By Kenneth L. Ancell

This paper traces the history and performance of a coal degasification project in the Black Warrior Basin of Central Alabama. The primary coal beds being degasified are the Mary Lee and Blue Creek. The area being developed for gas production is also scheduled for underground mining in two to seven years. The paper discusses the early data collection and evaluation. The coals are extremely gassy with some measurements in excess of 500 SCF/ton. Five experimental wells were drilled and produced. Geologic heterogeneities were encountered which affect the performance of the project. Drilling and completion practices together with well design considerations compatible with under- ground mining are discussed. Finally, the gas gathering and sales system together with the early production history is illustrated.

Jan 1, 1982

By C. A. Wert, K. C. Hsieh

Measurement has been made of the organic sulfur concentration in coal macerals using microanalytical techniques in the transmission electron microscope. This technique utilizes measurements of x-rays emitted by the sulfur atoms embedded in the hydrocarbon constituents and the bremsstrahlung x-rays generated in the matrix. It is a simple technique for thin specimens and yields reliable results. Although it can be used to measure the average organic sulfur content of coal, it is most useful in determining organic sulfur in extremely small volumes of material. Variations in organic sulfur content can be measured at a scale unimagined earlier. This TEM technique also has application for determination of organic chlorine, phosphorous, potassium and other elements often found distributed through the hydrocarbon constituent of fuels.

Jan 1, 1985

By Norman Hedley, Howard Tabachnick

The extraction of gold and silver from ores with alkaline cyanide solutions is well known. Cyanide solutions are also good solvents for many base metal minerals, particularly most of the copper minerals. Leaver and Woolf, who determined the solubilities of copper minerals in 0.10 pct sodium cyanide solution, showed that malachite, cuprite, chalcocite, and bornite are readily soluble in cyanide; least soluble are chalcopyrite and chrysocolla. The Mining Chemicals Laboratory of American Cyanamid Co. has studied the possibilities of using cyanide solutions for leaching base metals. In this article the authors present the results of their experiments with cyanide leaching to reduce the copper content of a zinc concentrate from 0.050 pct to the desired specification of less than 0.02 pct.

Jan 2, 1960

On October 20, 1964, in his Waldorf Towers suite, death came to Herbert Clark Hoover, 31st President of the United States. At his bedside were his two sons, Allan A. and Herbert Hoover, Jr. Many years of humanitarian and public service earned him the gratitude of millions here and abroad. The Nation mourned his death. For the mining fraternity and AIME in particular, the life of Herbert Hoover held particular meaning. During the years from 1895 to 1914 when he was actively engaged in mining, he conducted himself with extraordinary competence, energy and integrity. In the years following, when his qualities of administration and leadership literally forced him into the limelight, he continued his interest and lent his talents for the benefit of the engineering profession.

Jan 11, 1964

By Charles W. Merrill

WHETHER the valuable components in a mineral deposit can be mined and separated from the worthless matrix, processed, and marketed depends not only upon the natural factors and the physical and chemical techniques, but also upon many extrinsic factors relevant to the economics of the business of exploring, developing, and producing minerals. To meet a need for proper coverage of this specialized field of economics, the Mineral Economics Div. of the AIME has developed a plan for assembling a volume setting forth important factors affecting mineral enterprises other than those that lend themselves to solution through science or technology. The program has been considered by the Institute's Directors and they have approved it, subject to a decision of the Mineral Economics Div. to carry it out.*

Jan 8, 1954

By W. R. Phibbs

THE blast furnace of the Columbia Steel Corpn., at Ironton; Utah, was put in blast April 30, 1924, and its operation has presented some interesting problems. The coke for the furnace is furnished by 33 Koppers Becker type ovens of 15 tons capacity each. The coal is shipped from the company's mine at Columbia, Utah, which is approximately 123 miles from Ironton, and is probably the highest volatile coal that is being coked for blast furnace use in this country. The analysis of the coal is: PER CENT. Moisture 3.90 Volatile 39.00 Fixed carbon 51.10 Ash.... 6.00 Sulfur : 1.07 The analysis of the coke is: PER CENT. Volatile 0.55 Fixed carbon :...:.::: :..:.:: 89.70 Ash 9.75 Sulfur 1.05

Jan 1, 1928

By Edward Sampson

Despite the many industrial uses, the world market for silver as a commodity is far from free, being dominated by the U.S. Government both through acts of Congress and by policy of the Treasury Department. This discussion will consider aspects of supply, demand, and price with a view to the future. Changes in Sources of Supply: The world's peak production of silver, 278 million oz, was in 1937. In the 1850's world production was about 30 million oz, having risen from a yearly average of 11 million oz for the first half of the century. From 1860 to 1940 there was a steady rise, broken only by World War I and the depression of the early 1930's.

Jan 7, 1960

By Zhu Weishen, Xu Dongjun

In the 1st part of this paper a comparassion of the different methods for determining the modules of elasticity and deformation of hard rock is made. It is found that the plate bearing method has a serious shortcoming. The slit flat-jack method seems to be a mare reasonable technique, which is recommended as a desirable method for in situ testing. In the 2nd part, a new test method to determine the properties of deformation and strength of weak plane in rock mass is recommended. Then the relation of weak plane character to the character of stress-strain curve, the relation of normal stress to the character of shear displacement curve and the yielding criterion of weak plane are discussed.

Jan 1, 1982