Search Documents

By Geoff Blight

Jan 1, 1985

By D. E. Norquist, J. E. Moeller

The results of wear on marked balls, 4, 31/2, 3, and 2 in. diam are given. All balls were forged steel of practically the same chemical analysis and hardness. The results indicate that balls in a given mill for a given length of time will have equal diameter losses, regardless of size.

Jan 6, 1950

Executive R. C. ALLEN, Chairman ERLE V. DAVELER, Vice-chairman WILDER JUDSON R. M. ROOSEVELT G. B. WATERHOUSE Finance H. G. MOULTON, Chairman HENRY KRUMB PAUL D. MERICA H. T. HAMILTON, Consultant Admissions W. B. HEROY, Chairman GEORGE D. BARRON, Vice-chairman H. T. HAMILTON PHILIP KRAFT W. A. SINSHEIMER

Jan 1, 1937

By Paul M. Tyler

Higher freight rates and better methods of beneficiation now may make it more economical to open inferior deposits closer to a glass factory than to work higher-grade deposits farther away. Nature of impurities and special treatments as well as common practice of sulphuric acid leaching are described.

Jan 11, 1950

By L. A. Hanson

Jan 1, 1964

Jan 1, 1903

PRESIDENTS DAVID THOMAS 1871 R W RAYMOND 1872-1874 A L HOLLEY1875 ABRAM S HEWITT 1876 T STERRY HUNT 1877 ECKLEY B COXE 1878 - 1879 WILLIAM P SHINN 1880 WILLIAM METCALF 1881 RICHARD P ROTHWELL 1882 ROBERY W HUNT 1883 JAMES C, BAYLES 1884-1885 ROBERT H RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B POTTER 1888 RICHARD PEARCE 1889 ADAM S HEWITT 1890 JOHN BIRKINBINE 1891-1892 H M HOWE 1893 JOHN FRITZ 1894 J D WEEKS 1895 E G SPILSBURY 1896 THOMAS M. DROWN 1897 CHARLES KIRCHHOFF 1898 JAMES DOUGLAS 1899-1900

Jan 1, 1952

By John V. Beall

On January 1, 1948, we boarded the cage at 7 a.m. and were dropped to the 900 level of the Brunswick shaft. The previous evening, we had attended the New Year's party at the Miners' Guild Hall and as this soireée had not disbanded until the small hours of the morning, we had only had about two to three hours sleep. At the 900 level station, we fell in beside our mining partner, a Cousin Jack, who was known by all as Porky. Porky didn't say anything as we plodded down the drift, we didn't say anything either-in fact there was little conversation by anybody.

Jan 1, 1971

By Keith G. Papke

Jan 1, 1985

By Su Zhen

Based on the technical features of the Feng- huang-shan concentrator, the authors have designed a new scheme for optimal search and self-adaptive control in flotation process, in order to apply computer control to the concentrator. Hence, a plant test of optimal control in bulk flotation of copper and iron sulfides was successfully carried out. The control parameters are xanthate addition, pulp level, and amount of aeration, etc., in flotation cells. Two mathematical models of multiple parameters established by the authors were adapted and flotation efficiency was used as an objective function in the control.

Jan 1, 1984

Jan 1, 1953

By P. Barnes

The subdivisions of this account are numbered 27, 28, 29, 30, 31, 32, and 33, in the general series of construction accounts, and give the details of cost of the various items of the work, as noted below: Accounts 32 and 33 relate to hand-tools and to heaters, and, being quite small in total amount, are omitted in this statement.

Jan 1, 1879

By Roger Thunvik, Carol Braester

Excavation of cavities below the ground water level induces water influx from the surrounding aquifer. An estimate of the rates of flow prior to excavation operations may be of valuable information for the mining engineer. The present paper deals with water influx into cavities of the tunnel type, e.g., mine galleries, tunnels, etc. The solution of the flow problem was obtained by a numerical finite difference method. The results are presented in dimensionless form as a function of the parameters characterizing the location of the cavity in the aquifer.

Jan 1, 1981

By G. Richard Dreese, Harold L. Bryant

The coal mining industry has had a long history of successfully externalizing part of its costs. Thus the private or internal costs of coal mining have been minimized and the social or external costs have been ignored. The externalized costs have largely taken the form of water pollution from acid mine drainage and sedimentation of stream channels from eroding spoil banks and gob piles. The environmental problems created by strip mining are very conspicuous, so the public demand for legisla-

Jan 1, 1975

By John F. Frawley

This article in all probability will raise some serious doubts as to whether the coal industry-without a national, long-range commitment to coal-can, or should, attempt to meet the capital demands necessary to double coal production in the next 10 years. AMAX Coal, incidentally, doubled its annual coal productive capacity in the past five years from 11 million tons in 1969 to 22 million tons in 1974. Our 1973 annual report stated that we were aiming to triple our 1973 capacity to 50 million tpy by 1978.

Jan 5, 1975

By H. W. Mead, C. E. Birchenall

SELF-DIFFUSION of cobalt has been investigated by Ruder and Birchenall,1, 2 Nix and Jaumot,3 and Gruzin.4 The results for a given tem- perature differ by a factor of about six in the extreme cases with no really close agreement between any two sets of data. The first two groups of investigators employed the decrease of surface activity method. Since Ruder and Birchenall have shown that the values obtained from this method are sensitive to the surface preparation, it seemed desirable to perform a few check experiments by a method not open to this objection.

Jan 1, 1956

Arizona F. P. MATHEWSON, Chairman F. W. MACLENNAN, First Vice-chairman _CLYDE F. WEED, Second Vice-chairman F. D. GARDNER, Secretary-Treasurer Box 4097, University Station, Tucson, Ariz. ARTHUR CROWFOOT G. H. DOWELL HENRY F. FASTER R. D. LEISK Boston Meets first Monday each month, October to May, inclusive FREDERICK K. MORRIS, Chairman DANIEL CUSHING, Vice-chairman F. LEROY FOSTER, Secretary-Treasurer Rooms 6-202, Mass. Inst. of Tech., Cambridge, Mass. WILLIAM H. COBURN RUSSELL 01550K

Jan 1, 1934

Elected Died 1884 *ADDY, MATTHEW 1896 1894 *ALLFN R B 1896 1874 *AMIOT, H 1892 1886 *AMSLER, CARL 1894 1895 *ÅNGSTROM, CARL 1901 1895 *ARMSTRONG, JOHN F 1898 1882 *ARNOLDS, HUGO 1886 1875 *ASHBURNER, CHARLES A 1889 1872 *ASIIBURNER, WILLIAM 1887 1883 *ATKINS, C M , JR 1885 1897 *AYERS, WILLIAM 1898 1885 *BABCOCK, GEO H 1893 1884 *BAILEY, EDWARD 1889 1880 *BAILEY, JACKSON 1887 1900 *BALLOU, FRANKLIN 1903 1886 *BARNES, F W 1892

Jan 1, 1910

By G. F. Swindle

This paper discusses a Personal Computer (PC) software package that reduces the time required to evaluate a mineral reserve. It provides for: •Entry of borehole data onto PC diskettes and the creation of a borehole database; •Capture of map data using an attached X-Y digitizer; •Calculation of uniform square grids for thickness, mineral qualities, overburden ratio, etc., •Compilation of multiple such grids into a digital model, and iterative evaluation of the model with the user applying constraints and cut-off values; and • Graphic display of grid cells (blocks) showing which cells failed, and on which constraint(s), and a complete reserve report showing tonnages, averages, histograms, and quality arrays.

Jan 1, 1985

By R. R. Odman, O. N. Lofgren

At the planning stage for this plant it was scheduled that the plant operate at a low energy consumption. After start up in 1973 it was established that outcome was even better than the forecast. In view of the 1977 ore market it was decided to operate the plant at half capacity. This initiated efforts to reoptimize the process in order to hold back expected increase in energy consumption. The result from this work proves that a detailed study and tuning of the process can not only avoid expected increase, but also reduce specific energy consumption.

Jan 1, 1983