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Jan 1, 1947

By Gregg A. Scott

Upper Stillwater Dam is to be a roller-compacted concrete gravity structure, founded on nearly horizontally bedded sandstone and argillite rock. An overview of the testing and analyses used to evaluate the adequacy of the foundation relative to deformation, seepage, and stability is presented.

Jan 1, 1984

Jan 1, 1947

By James E. Breland

A case study of tangible and intangible costs incurred by a coal mining company for meeting the requirements of the Federal Coal Mine Health and Safety Act of 1969 is discussed. For clarity, the data is presented on a "before and after" basis, with special emphasis on safety records, costs, and production performance. The cost figures have been subjected to outside verification.

Jan 1, 1975

By R. E. Stewart

The major mining companies of the world all face the problems associated with investing in new mining ventures. In particular, investment in foreign countries - whether these are advanced or developing countries - requires careful consideration. A thorough analysis of all the possible risks must be undertaken, so that realistic decisions can be made. Some of the points to be considered are outlined in this paper.

Jan 1, 1977

John Edward Stead, a past-president of the British Iron and Steel Institute, and an Honorary Member of this Institute since 1906, died at his home at Redcar, Yorkshire, on Oct. 31, 1923, after a long illness. For many years, Mr. Stead had been recognized as a leading authority in chemical and metallurgical matters, particularly those relating to iron; he gave freely of his experience by the contribution of papers to the twenty-eight technical societies in which he retained his membership as recently as 1920. He had been honored with the Doctor's degree by three English universities, and was elected a Fellow of the Royal Society 1219

Jan 1, 1924

By James B. Fletcher

Leaching of the block caved mine from 1941 through 1970 is described, and the improvements made are listed. Detailed is the increased knowledge of leaching gained through this operation, including methods used in forecasting production, prediction of the economical end point, rate of recovery, and ultimate recovery.

Jan 1, 1972

By G. W. Dopson, P. A. Korpi

The angular spiral lining system reduces energy consumption and grinding media consumption in grate discharge ball milk. This paper discusses the effect of this lining system on mill product size distribution. Performance comparison of a grinding circuit outfitted with angular spiral liners in ball mills are made with respect to standard double wave-liner installations. The angular spiral lining system was developed by Waagner-Biro of Austria. The installation of this lining system at Magma Copper Co. is the first of its kind in a grate discharge ball mill used for wet grinding.

Jan 1, 1983

By Harold A. Krueger

FACILITIES and mining operations of the National Lead Co., St. Louis Smelting and Refining Division, near Fredericktown, Mo., are situated in a famous mining area. Copper, lead, nickel, and cobalt have been mined here for more than 100 years, work having been started on a high sulphide copper outcrop in 1847.

Jan 8, 1953

By Lester F. Engle

Books have been written, complex charts drawn, great batches of punched cards handled by ever increasing numbers of computers, and innumerable meetings held-all for the purpose of making effective the ultimate objective of new, revised or improved process facilities. It is to the credit of management, engineers, and others that in the vast majority of cases, the outcome of their work has been technically sound and economically rewarding. There is a way, however, to insure even better results.

Jan 5, 1966

By Dominique François-Bongarçon

A new method for open-pit design has been devised by G. MATHERON and the writers: it replaces the search for an optimum contour by the determination of a parametrizing function. The isovalue curves of this function give the optimum pit design corresponding to varying economic parameters; The method is described and indications are given about the corresponding program. Simulated data have been processed by the program and by a standard program using LERCES-GROSSMAN graphical method: the comparative results are described.

Jan 1, 1977

By Alexander L. Holley

Jan 1, 1879

By F. Milton Lewis, Roshan B. Bhappu, James L. Coburn

FOREWORD-To comminute is to pulverize, but, in mining technology, "comminution" includes all the multiple crushing and grinding operations on ore, rocks, coal, and certain other bulk materials. The primary objective of this two-part article series is to provide the reader with basic information and guidelines for designing comminution systems. Part One is confined to ore processing operations, where size reduction is required to liberate the valuable minerals so that they may be concentrated and recovered. Part Two will illustrate various design techniques through practical examples.

Jan 9, 1976

By William D. Schwab

In the technical literature of 1965 and 1966, there were several papers about future power for mining and construction equipment. Most of these papers made the same predictions: •More power •Better reliability and durability •Ease of service and maintenance •Operating economy •The possibility of future environmental concern •The entrance of the gas turbine In the five years that have since passed, some of the 1965-66 predictions have at least partially come true, while others have not been fully realized. Actually the list still appears sound today. Priorities may have changed and details may be different, but the main points cover the requirements for future prime movers quite well.

Jan 1, 1971

By D. R. Mitchell

Accent is on mechanization, more preparation plants - Competition from other fuels remains biggest problem.

Jan 2, 1953

Assaying, mineralogy, and geology appear in ancient records as early as mathematics, physics, and chemistry. Agricola was the first author to unify the earth sciences, the mineral extractive industries and the mineral processing industries. His text, De Re Metallica, published in Latin in 1556, is recognized as the first technical literature. In 1702 mining instruction was started at Freiberg, Germany. The purpose of this school was to train skilled workers, a program corresponding to present-day, on-job, vocational-technical, upgrading extension training. Formal instruction in mining engineering began at Schemnitz, Hungary, in 1763, at Freiberg, Germany, in 1766, and at St. Petersburg, Russia, in 1773. It is interesting to note that these three schools initiated instruction in mining engineering before formal instruction in civil engineering began at Paris, France, in 1775. Early mining engineering, 1763-1900, was expected to cover all eventualities in the mineral industries. Optional curricula were offered early in the 20th Century but did not reach into all branches until after World War I. Specialization crystallized during World War II under three organic units: (1) Earth Sciences; (2) Mineral Engineering; (3) Mineral Technology, the three together constituting the mineral arts and sciences of the modern world (Fig. 10).

Jan 1, 1950

By B. F. Fackenthal

The earliest history shows that, in the reduction of iron-ores, natural draft was used to supply the blast, and that, when artificial blast was first used, it was supplied by leather bellows, usually made of skins, which were worked by the feet or hands, the blast entering the furnace through one tuyere or nozzle. The prehistoric bellows and its tuyere or nozzle are still in use in some form wherever iron is made. The original Durham furnace, built in 1727 at Durham, Pa., which was one of the earliest blast-furnaces in this country, was blown with a bellows, the power being supplied by a waterwheel. The old records show the purchase of leather at various times to repair the bellows, and mention the freezing of the water-wheel as one of the causes for going out of blast. In the early days of our iron manufacture but one tuyere was used; in fact, a cousiderable number of charcoal-furnaces continued to use but one tuyere down to recent years. I am

Jan 1, 1899

By Guy R. Johnson

In view of the attention now directed to the development of the iron-ores of Virginia, and of the frequent reference in the Transactions of the Institute to the Longdale mines, it is presumed that a brief account of the methods of working and surveying these mines will be of interest. For a better understanding of such a description, a few words will be said concerning the geological character of the ore-deposit. Professor Rogers says in his preliminary report of 1835, that this deposit has " more of the character of a true vein than is usually

Jan 1, 1892

By Kalanadh V. S. Sastry, D. W. Fuerstenau

A locked-cycle balling procedure has been designed to simulate continuous, closed- circuit balling drum operation in the laboratory. By this method, it is possible to simulate the surging in green-ball production rate and circulating load that is experienced in industrial balling circuits. Through an investigation of the effect of feed rate on the stability of the locked-cycle, balling process, it was found that higher feed rates lead to increasing instability in the process. An analysis of the experimental ,results is presented and the utility of the locked-cycle experimental technique for evaluating the stability of an industrial balling drum operation is discussed.

Jan 1, 1976

By John J. Reed

The mines of southeast Missouri's Lead Belt have been in operation since 1864, almost 100 years. During this period about 10 pct of the total ore available has been left in place as pillars, and this now represents the best ore reserve left to the older mines. St. Joseph Lead Co. has been investigating various plans of pillar recovery for several years. The example to be described is only one possible approach under a specific set of conditions. Conditions vary greatly in the different areas within the Lead Belt, and the same approach would be entirely in- adequate in certain other areas, but there are important sections where this system is clearly applicable.

Jan 7, 1959