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By R. L. Atwood

This paper discusses the metallurgical and Manufacturing input to Merrill-Crowe plants. Topics treated are pregnant solution chemistry, clarification, degassing, zinc addition, product filtration, accounting, and costs.

Jan 1, 1985

Jan 1, 1922

Jan 1, 1935

Jan 1, 1923

The Library of the above-named. Societies is open from 9 A. M. to 10 P. M. except on holidays. It contains about 70,000 volumes and 90,000 pamphlets, including sets of technical periodicals and publications of scientific and technical societies Members of the Institute, with few exceptions, are forced to spend a portion of their time in localities isolated from sources of information. To these the Library, through its Library Service Bureau, can render valuable service through correspondence; letters requesting information will receive especial attention. The Library is prepared to furnish references and photographic copies of articles on mining and metallurgical subjects; to determine the existence of mining maps, and to furnish general information on the geology and mineral resources of all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape.

Jan 5, 1918

By J. Th. G. Overbeek, R. Schumann, P. L. De Bruyn

THE technique of concentrating valuable minerals from lean ores by flotation depends upon the creation of a finite contact angle at the three-phase contact, mineral-water-air. If the mineral is completely wetted by the water phase, contact angle zero, there is no tendency for air bubbles to attach themselves to the mineral. However, when the contact angle is finite, the surface free energy of the system, water-air bubble-mineral particle, can be diminished by contact between the bubble and the particle, and if not too heavy the mineral will be levitated in the froth. With a few exceptions, all clean minerals are completely wetted by pure water. Thus the art of flotation consists in adding substances to the water to make a finite contact angle with the mineral to be floated, but to leave the other minerals with a zero contact angle. The contact angle concept and experimental measurements of contact angles have played important roles in flotation research for several decades.1-3 Nevertheless, there remain unanswered some basic questions as to the scientific significance of the contact angle and the nature of the processes by which flotation reagents affect contact angles.

Jan 5, 1954

By George Scott

MANY requests for information as to the possibility of washing coals to some predetermined percentage of ash or sulfur have suggested that the producers aim to satisfy some degree of purity set by the user of the fuel, rather than to attain the greatest economic benefit to all concerned. This paper is written to show that the highest economic purity of washed coal can be determined from washability studies of the raw coal, costs of mining and washing coal, and data on the effect of ash and sulfur on the value of the coal for the particular use for which it is intended.

Jan 1, 1929

By Jorge Rodríguez Velarde

Dado que la extracción de metales exige revisar la tecnología existente para así proveer de los metales necesarios que se requieren para suplir esas exigencias. En ese sentido, el presente texto describe la lixiviación bacteriana como la tecnología de vanguardia para recuperar elemetos metálicos a partir de materiales mineros marginales. Los sulfuros metálicos tienen propiedades electroquímicas que pueden transferir electrones, generando reacciones tipo redox. Por ello, los thiobacillus thiooxidans y los thiobacillus ferrooxidans para su metabolismo, requieren ganar energía de aquellos electrones ubicados en orbitales de un alto nivel energético. De esta manera, una bacteria puede catalizar un proceso redox con un sulfuro metálico. La pérdida de electrones en un sulfuro significa enlaces rotos y esto origina la disolución del sulfuro metálico. Así, se postulan dos mecanismos por el cual se produce la disolución del sulfuro.

Mar 1, 1983

Jan 1, 1942

Jan 1, 1938

Jan 1, 1938

By Muhammad Tawalbeh

The calculated temperature history of a single particle of MgCl2 hydrates when it came in contact with fused salt electrolyte at 650 °C was determined using the measured heat transfer coefficient for the molten salt bath at 650 °C. The calculations revealed that the entire interior of the particle reached the temperature required for the formation of MgOHCI from hydrated MgCl2 in less than 2 seconds. This was much less than the time required for dissolution of the prills as observed in experiments. It is very likely that the formation of MgOHCI during prill dehydration and dissolution is a result of hydrolysis in the interior of the prills.

Jan 1, 2004

By E. J. Gleim

Many people consider the mining of coal to be an extremely hazardous occupation; but it should be remembered that most large industries have to meet special conditions which, if not dealt with properly, might become hazards to life and property. Mining men may not always be fully aware that some practices and certain equipment that is incorrectly designed or maintained can lead to dangerous conditions. In endeavoring to help the coal-mining industry to prevent accidents and disasters, the Bureau of Mines has engaged in a program of education on conditions and practices that must be avoided. An effective way to teach safety is by visual demonstration. For example, it is generally known that certain kinds of electrical flashes have ignited explosive atmospheres in mines, but actually to see and hear explosions caused by electrical sparks of different size and character under laboratory control is likely to teach a much more emphatic and lasting lesson than would be learned by merely reading about them. The interest manifested by those who witness the demonstrations seems to prove that this is true. The purpose of the demonstrations is not to discourage the use of electricity in mines, but rather to indicate what types of equipment (including some generally regarded as harmless) can ignite gas and what safeguards have been developed to prevent such ignitions. It is hoped that this information will improve the ability of mining men to cope with underground hazards.

Jan 1, 1937

Jan 1, 1911

By Bruce Johnson

This paper is not written to "break new ground" in computer applications; it is just a treatment of how an operating metal mine utilizes a mainframe computer for planning, analyzing, and reporting on the ventilation and cooling systems. The Unisys mainframe computer at the mine site is used in programs that analyze the ventilation network, keep records on various ventilation installations, calculate the results of measurements and produce reports on ventilation conditions in the working places and on the main air distribution, and plan and analyze the cooling system. All the programs are interactive to terminals. There are a series of data files that are generated by some programs which may be used by other programs. Most of these programs have been developed in-house. The computer is also used as a word processor via a vendor-supplied text editing program to produce memos, letters, and to keep up-to-date lists of equipment used.

Jan 1, 1989

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Jan 1, 1938

By Cleland N. Conwell

Intermittent coal mining has been conducted in Alaska for over a century. The first report of coal in Alaska was by the Veechy expedition of 1826 and 1827. Whaling ships used coal from Corwin Bluff near Cape Beaufort during the early and latter parts of the 19th century. The first coal mine in Alaska -- and probably the oldest in the Pacific coast of North America -- was opened by the Russians at Port Graham on the southwest tip of the Kenai Peninsula. The mine was operated from 1855 until 1867 when the United States took possession of Alaska. From 1880 to 1915 coal mining was carried on intermittently at several localities including Unga Island, Herendeen Bay, Chignik Bay, Kachemak Bay, and several points along the Yukon River. Small coal mines along the Yukon River provided fuel for the river steamers traveling from St. Michaels to Whitehorse. The area of sustained coal production began with the completion of the Alaskan Railroad from Anchorage to the Matanuska coal field in 1916 and to the Nenana field in 1918. Coal production continued to increase until 1953, at which time the oil and gas fields in Cook Inlet were developed. Oil and gas eventually replaced- the Matanuska coal as a means of providing heat and power. The military in the Anchorage area shifted from coal to oil in 1967 causing a decrease in production. The increased demand for electric power in the Fairbanks area offset the decline and coal production started to increase. In 1969-1970 the Golden Valley Electric Association constructed a mine-mouth power plant 70 miles southwest of Fairbanks near Healy and a power line to Fairbanks. LOCATION OF COALS IN ALASKA Coals are found in all geographical subdivisions of Alaska. Coal in Alaska ranges in age from Carboniferous to Tertiary, and grade from lignite through anthracite. Figure 1 shows the locations of Alaskan coal fields. The only fields that have been developed extensively are the Matanuska and Nenana. Figure 2

Jan 1, 1972

By R. H. Lee

So far as I am aware the references to the " kerosene blow-pipe" in the Transactions comprise only a skeptical opinion from Mr. Witherow (ix., 70), and accounts of the use of the blow-pipe by Mr. Witherbee (xiii., 675) and Mr. Gayley (xiv., 779), together with brief remarks by Mr. Weeks and Mr. Kennedy on Mr. Witherbee's paper. The subject can scarcely be considered novel, in view of these references, yet it is not so far exhausted that an additional account of the successful application of the blow-pipe would be out of place, especially if accompanied with some new details and a drawing of the apparatus itself, showing its simplicity and safety. Some time ago, owing to a variety of causes, my furnace was working very badly, the troubles culminating suddenly one morning in a chilled hearth, solid from the bottom to the tuyeres, with the exception of a narrow passage-way from above to the cindernotch, which remained open. Through this we continued to flush and cast, with the prospect of a long and troublesome siege, in working down to the iron-notch. At the end of two days matters had not greatly improved, and we seemed no nearer the desired result than on the morning of the chill, when, at the suggestion of Mr. Farrell, of Glamorgan, I decided to use the coal-oil blow-pipe; the intention being to cut a hole from the iron-notch up to the tuyeres, and then let the furnace melt out the chilled mass. In four hours from the time of starting, the hole was made and

Jan 1, 1887

By H. M. Morse

During the year 1942 there were 66 wildcats drilling in Mississippi. One cored in oil sand, the Macro Drilling Company's Longbell No. I in Clarke County, but as yet it has not succeeded in recovering the oil. These drillings broughi to light five salt domes, two of which had heavy oil showing; one drilled by the Magnolia Petroleum Co. in Warren County, and

Jan 1, 1943

By H. M. Morse

During the year 1942 there were 66 wildcats drilling in Mississippi. One cored in oil sand, the Macro Drilling Company's Longbell No. I in Clarke County, but as yet it has not succeeded in recovering the oil. These drillings broughi to light five salt domes, two of which had heavy oil showing; one drilled by the Magnolia Petroleum Co. in Warren County, and

Jan 1, 1943