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By Raymond Brandon, Marshall Pease

A pattern for providing a large utility, The Detroit Edison Co., with an adequate fuel supply is outlined. From the standpoint of both fuel procurement and utilization, consideration has been given competition relationships, fuel properties as well as operating conditions that must be met to provide dependable service and reliable plant operation.

Jan 2, 1951

By William B. Plank

ENGINEERING educators and industries are worried about the engineering manpower shortage that is predicted as a result of the increasing demand for trained engineers not only by industry but by the armed services. This is in the face of a decreasing supply, as is shown by this and other studies. Not only has the number of entering freshmen been decreasing since 1947, because of a decrease in the number of high school graduates entering engineering, but the total number of high school graduates will continue to decrease until 1958 because of the lowered birth rate during the depression years.

Jan 8, 1951

By H. T. Wyatt, A. S. Baptie

The Ten Section field is approximately 10 miles southwest of Bakers-field, Kern County, Calif. (Fig. 1). There is no surface evidence of the existence of the Ten Section structure, which subsurface exploration has shown to be a gently folded, anticlinal dome. Regionally, this field occurs as a fold in the deeper beds of the gently rolling floor of the San Joaquin Valley. It is on the easterly slope of the valley, its position with relation to the axis of this syncline not having been determined. The field was discovered by Shell Oil Co. with the completion of well Stevens A-l, on June 2, 1936, at a depth of 7888 ft. The location for this

Jan 1, 1938

Jan 1, 1923

Jan 1, 1923

By C. H. Mathewson

BeRyllium, magnesium, zinc and cadmium, together with mercury, constitute a coherent sub-group of the periodic system and these metals, excepting mercury, have been studied in sufficient detail by the new X-ray diffraction methods to prove their common adherence to the hexagonal close-packed type of crystal structure with a progressive increase in axial ratio as we pass through the group from beryllium to cadmium. The first four columns of Table 1 summarize the data on crystal structure of these metals reported in the International Critical Tables.' The last two columns are based on results obtained in the present investigation. Twinning has often been observed in zinc and cadmium. The general aspects of this twinning are abundantly illustrated by photomicrographs, diagrams, etc., in the papers by Romig, and Mathewson and Phillips reported to this Institute in 1927.2 A determination of the composition

By G. S. Rice

Undoubtedly there is a serious problem through the juxtapostion of gas and oil wells and coal mines, not only at the present time, but possibly of far more serious import for the future.

Jan 1, 1915

By L. A. Wright

Union Carbide Corp.'s Pine Creek mine in California is the largest known tungsten deposit in the West, and the producer of well over five million tons or ore to date. Located 21 miles northwest of Bishop on the eastern slope of the Sierra Nevadas, the mine is also a source of molybdenum and copper and it was the quest for the molybdenum which caused the mine management to undertake a pillar recovery program. GEOLOGY For a full discussion on the geology of the Bishop tungsten district and the Pine Creek mine, reference is made to Special Report 47, Calif. Div. of Mines. The deposit lies along a 3000 ft segment of the contact between quartz monzonite and the marble that flanks the west side of the north portion of the Pine Creek pendant. All the components of a typical contact metamorphic tungsten deposit are developed; these consist of tactite, light colored calc-silicate rock and quartzose rock.

Jan 5, 1964

By W. E. C. A. B. Eustis

(Read at the Philadelphia Meeting, February, 1878.) IN September last I had my attention called by Mr. R. G. Leckie to a deposit of nickel in the township of Orford, province of Quebec. In many ways it has proved to be a subject of great interest. As this ore is, as far as I can learn, entirely new in mineralogy and metallurgy, it has seemed to me that it would be a matter of interest to the Institute to have laid before it, in a short paper, the peculiarities I have met with in studying it. This deposit of nickel was first described by Dr. T. Sterry Hunt, our President, in the Geology of Canada, 1863, p. 738, in the following terms : "The general diffusion of nickel throughout the magnesian rocks of the Quebec group has been already noticed. It has, however, never been met with in any considerable quantities in these rocks, although workable deposits of its ores may reasonably be looked for

Jan 1, 1878

By Robert S. Schecter, Paul M. Bommer

This paper presents the development of and results from a computer model of in situ uranium leaching. This model uses a streamline-concentration balance approach and is useful with a wide range of reservoirs. It can be used with any type of well system, in a reservoir with or without boundaries, and with any form of descriptive kinetics. The model also includes the effects of dispersion and consumption of oxidant by minerals other than uranium. The effects of areal sweep, variable uranium concentrations, variable permeability, and the presence of oxidant consumers on uranium production are shown and discussed.

Jan 1, 1979

By Donald W. Jenkinson

Many types of gravity concentration equipment have been employed throughout the years since beneficiation of materials has been practiced. These include jigs, concentrating tables, vanners, sluice boxes, heavy media cyclones, and static heavy media separators or sink-float separators. In the beneficiation of coarse aggregate for concrete mixes, static heavy media separation employs the same principles of gravity concentration involved in separating lead-zinc ore, dolomite, limestone, diamonds, manganese, iron, and many other minerals. In aggregate beneficiation, as in most metallurgical operations, sink or heavy fraction is the product. The undesirable portion of coarse gravel is usually much lighter than the desirable particles, allowing most aggregates to be amenable to gravity concentration methods.

Jan 7, 1960

By George W. Becker, Blair R. Benner, Ronald J. Roman

A computer model for the leaching of oxide copper heaps is developed and verified in laboratory tests. The model can be used to scale-up laboratory test data and to simulate the results of various operating philosophies on heap leaching. The model is applicable to leaching processes where the rate of leaching is controlled by a deficiency of reactant or diffusion of a reactant through the leached rock. Several examples are presented showing the sensitivity of the recovery vs. time curve to the variables in leaching.

Jan 1, 1975

By T. M. Anderson

From the start of production in 1915 until 1948, underground block caving operations accounted for all of the ore production of Inspiration Consolidated Copper Co. Open pit development work began in 1947, and ore production from the open pit commenced in March 1948. Thus began the transition from underground to open pit mining which continued until August 1954. Since then, open pit mining has accounted for all ore production which presently averages 105,000 tons of ore and 75,000 tons of waste rock each week. Open pit mining operations at Inspiration is carried on in two separate pits-the Live Oak Pit and the Thornton Pit. The Live Oak Pit covers an area of approximately 1500x3000 ft and the Thornton Pit, 2500x2000 ft. The geographic centers of the two pits are 4000 ft apart and, at their nearest point, the surface slopes are 500 ft apart.

Jan 1, 1961

By Robert B. Hill

A history of gravity classification shows the development of many types of equipment with several prominent types continuing in use today. Part of the development and evolution is the spiral classifier. Data will be presented showing characteristic size separations in a closed circuit grinding operation. Comparisons with hydro- cyclone operation will be shown including operating cost comparisons. Effects of variables will be shown in spiral classifier operation. Finally, other uses for spiral classifiers will be described.

Jan 1, 1982

By Ta M. Li

Application of an hydraulic mining system to a troublesome overburden removal project has unlocked an estimated three million tons of ore reserves at Caland Ore Co., Ltd.'s open-pit iron operation in Ontario, Canada. The mine, operated by Caland under a 99-year lease and royalty agreement with Steep Rock Iron Mines, Ltd., would have been forced to curtail its mining operations later this year as the economic limits of the original pit design were being reached. As a result of the stripping program, which uses a tandem set of Marconaflo jet slurry systems, Caland officials now estimate that mining will continue into 1977. These reserves, added to existing ore stockpiles, are expected to sustain the firm's pelletizing operation well into 1981. In addition, Caland engineers are initiating studies to continue mining since the ore body, to date, has yet to bottom out.

Jan 10, 1976

By W. C. Kerr

When Agassiz and his party of geologists commenced their exploration of the interior of Brazil and the Amazon region, one of the first and, to the last, one of the most novel and striking phenomena which met them everywhere was the great depth of decomposed or partially decayed rock in situ, which mantles, and for the most part conceals, the underlying strata. The same facts strike all geological observers from the North who happen to penetrate the middle and southern latitudes of the Atlantic States. In North Carolina, e. g., the entire middle and western regions, outside of the Quaternary clays, sands, and gravels of the East,—that is, all that portion of the State occupied by the Archæan and Mesozoic rocks,—show everywhere this peculiarity, so new to those accustomed to glaciated surfaces. Not only do the hills and slopes, the mountain chains and

Jan 1, 1880

By Donald W. Mitchell

MINE operators have a choice of several classifications of mechanical loaders. Within each classification there are many types and makes available. Table I lists loaders on which manufacturing data as to operating characteristics are available. This paper discusses the conditions met in a mine as they affect these characteristics. It is assumed that management will provide satisfactory engineering, supervision, power, maintenance, loader service within a concentration of workings, and a balanced working cycle served by balanced production equipment. These are factors which affect the optimum operational efficiency of a loader. The conditions which determine loader choice are:

Jan 5, 1951

By Milton E. Wadsworth, Edward M. Eyring

Better understanding of solid surfaces and their associated adsorption products is of both academic and practical value. The study of detergents and their behavior in cleaning surfaces is fundamentally related to the nature of the products adsorbed and their ability to compete for certain surfaces. Similarly in flotation, the nature of the adsorbate before and after adsorption is basic to clear understanding of the process. The recently developed pellet technique employing infrared spectroscopy provides a powerful tool for the study of solid surfaces. Absorption bands, which are infrared-active, may be observed for adsorbed products. Also any changes in the surface substrate that occur as a result of adsorption may be detected by means of differential spectra

May 1, 1956

By Leon O. Hart

The nickel-chromium alloys of importance are those containing iron and those free from iron. The most important alloys containing iron, with regard to high tonnage, are the nickel-chromium steels. Straight nickel steel was introduced about the year 1889, but it was not until 1895, when it was found that the addition of chromium greatly increased the strength and resistance to shock, that nickel-chromium steels came into use. The three types of nickel-chromium steels developed at this time were: Type 1, containing 3.,50 per cent. nickel and 1.50 per cent. chromium; type 2, containing 2.00 per cent. nickel and 1.00 per cent. chromium; and type 3, containing 1.50 per cent. nickel and 0.50 per cent. chromium.

Jan 1, 1921

By Milton C. Neul

As recently as the mid-1930's, steam and rail haulage were still the primary means of moving large quantities of rock. However, 2- to 5-ton standard on-highway trucks were beginning to be used in the mining industry's efforts to lower haulage costs. It was quickly obvious that rubber-tired equipment was more flexible, faster and more maneuverable. The trend towards haulage trucks had begun. Now while savings were being realized, the severe operating conditions encountered in open pit operations proved too much for the lightly constructed frames, gasoline engines and highly inflated tires. As a result, a few years later, the first 10 to 15-ton, two-axle heavy duty trucks were designed specifically to operate under off-highway conditions.

Jan 3, 1966