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By Richard A. Arnold

The evolution of planning processes in the United States from the early 1900's is briefly examined. From one year operating budgets, planning processes have evolved into sophisticated analyses of alternative long-term future strategies and the management issues and practices which relate to their implementation. Increasing complexity within the business environment has led to numerous planning methodologies and extensive use of computers to analyze operating and financial information. All of these developments, however, have not supplanted the real need for decision-makers to continue to give important weight to the intuitive or soft data inputs into the planning process.

Jan 1, 1985

By M. Dubrovsky, J. W. Evans

A laboratory scale cell (approximately 50 amps current) equipped with a fluidized bed cathode was used in a study of the electrodeposition of cobalt from acidified aqueous sulfate solutions The effect of current density (in the range 0.1 to 1 amp/cm2 of diaphragm), cobalt concentration (4 8 to 100 glliter) and catholyte pH (1 35 to 6 2) on current efficiency and energy consumption were determined. Generally the current efficiency increased with increasing current density and cobalt concentration Current efficiencies were comparable to those reported in the literature for conventional electrowinning

Jan 1, 1981

By D. M. McFarland

A FEW years ago a novel electric detonator known as the split-second or millisecond delay electric blasting cap was introduced for use in quarry blasting. Regular electric blasting caps fired in series may be depended upon to fire within a millisecond or so from the first to the last in a series. Regular delay electric blasting caps are provided that fire one period after the other period in intervals of 1/2 to possibly 1 l/2 sec. Most split-second or millisecond delays are designed to fire one period after the other period in possibly 25 to 50 millisecond intervals. The ear is not capable of detecting time intervals of this magnitude.

Jan 11, 1950

By E. E. Malouf

Leaching is rapidly becoming an important adjunct to mining operations. A summary of various leaching operations is presented showing the role of these activities to the successful operation of the mining venture. The summary will include recent developments in dump, heap, and in situ leaching of copper and uranium ores. It will include a discussion on the expanding impact of industrial and academic research on leaching as a mining tool, showing the interplay of chemical kinetics and biogenic activity.

Jan 1, 1973

By J. F. Cuderman

A technique using propellants has been developed for producing multiple fractures about a wellbore. The use of propellants having a range of burn rates permits precise control of combustion gas release and thereby of borehole pressurization. The pressure rise- time is the key variable governing fracture behavior. The peak pressure attained is of secondary importance and appears to be a function of in situ stress and loading rate. The fracture geometry is governed by the in situ stresses and pressure risetimes. The major fractures occur along the principal planes of stress and along apparent planes of maximum shear stress.

Jan 1, 1984

By E. C. Pechin

AT the September meeting of the Iron and Steel Institute of Great Britain, Mr. Charles Wood, of the Tees Iron-works, read an interesting paper on "Further Improvements in Blast-Furnace Hearths," which was followed by an animated and instructive dis¬cussion. If the durability of hearths and in-walls is a matter of interest in England, where furnaces stay in blast from eight to twenty years, it

Jan 1, 1876

By Lawrence Adler

For openings in bedded rocks, analyzed by simple beam theory, it has been shown that roof loads can be shifted from one support to another.' This transfer is effected by controlling the relative deflection of adjacent supports. If this action is used to reduce loads in the props or bolts and increase them in the ribs or pillars, it could be productive of economies averaging 30 pct. Such savings can be realized by: 1) using smaller artifical supports such as props and bolts, and 2) increasing loads in the rib to induce eventual failure for longwall caving. Since the rib is relatively load-insensitive, it provides a natural load sink. However, caution must be used in applying such permissive deflections, for while the supports are being handled properly, the stresses in the roof itself are very sensitive to such manipulations.'

Jan 5, 1960

W. H. BLAUVELT (author's reply to discussion *).-The prevention of smoke from byproduct-oven plants is not as simple as would appear from Mr. Moss's statement. All well designed byproduct-oven plants are equipped with ample exhauster capacity, and the suction on the ovens is controlled by highly sensitive pressure governors that control the pressure within a fraction of a millimeter. Of course, this apparatus can get out of order, causing the batteries to smoke, but this does not often happen. As stated by Mr. Thompson, the smoke produced is made almost entirely during the time of charging the ovens, when they are cut off from the hydraulic main. The amount of smoke that escapes at this time is extremely small, compared with -the amount produced by a beehive-oven plant, but the mechanical difficulties in preventing any escape of smoke at charging time are considerable. Several devices are in operation at a number of plants which collect most of the smoke made during charging and several devices are being worked on for its complete

Jan 12, 1918

By C. G. Albert

The literature of paper technology contains a number of articles having reference to developments in the field of coating and filler clays for use in paper manufacture. Much of this information has not been included in mining publications and has therefore not been readily available to all in the mineral industry. Recent developments in this field, including spray drying of clays, are presented here. U. S. Bureau of Mines figures for 1952 indicate that the paper industry consumes more than 50 pct of all kaolin produced and sold in the U. S. As most of the kaolin used by the industry comes from Georgia producers, the fraction of their output destined for paper use is thus appreciably higher than 50 pct. Small wonder that the kaolin industry, especially in Georgia, is highly sensitive to the quality requirements of paper mills and must respond promptly to technological developments in paper manufacturing.

Oct 1, 1955

By Gail Moulton

THE oilfields in Illinois are located principally along the LaSalle anticline in the southeastern part of the state. The oil produced comes most largely from beds of Pennsylvanian and Mississippian age, but there is an increasing important production from deeper horizons, as will be noted under new development. The oil is largely of paraffin base, and has an average specific gravity of about 35° Baume. The rank of Illinois as an oil producer has dropped from third since 1913, when its production was exceeded only by that of California and Oklahoma, to eighth in 1923. This has been the result of failure to find new pools of considerable size to offset the declining production of the old wells and of the greatly increased production of some of the other states. The noteworthy features of petroleum production in Illinois during 1924 are: the low rate of decline for the state as a whole; the smaller percentage of dry holes; and the larger average initial yield of the new wells.

Jan 3, 1925

By E. M. MacKevett

The only source of uranium ore in Alaska that has been mined commercially is the Ross-Adams de- posit, a gently inclined, fusiform orebody in alkali granite in which uranothorite and uranoan thorianlte are the chief ore minerals. In mode of occurrence, apparent genetic association with the granite, and to a lesser extent in mineralogy, this type of deposit is uncommon. The mine is in the southern part of Prince of Wales Island (Fig. 1) at an altitude of about 950 ft on the southeast flank of Bokan Mountain. A steep unpaved road 1 ¾ miles long leads to the dock on the West Arm of Kendrick Bay, which can be reached by boat or seaplane from Ketchikan, some 35 miles to the northeast.

Jan 9, 1959

By AIME

DURING the Revolutionary War an iron mining industry was born in the Adirondack region of New York State. New York State ores provided the iron from which were forged the links of the chain that, strung across the Hudson River, successfully kept British vessels from ascending. The industry flourished for a while and then became dormant. For the successful prosecution of World War II, the magnetite mines were revived and given considerable aid in the form of government financial support. The complete story appeared in a special issue Of MINING AND METALLURGY published in November 1943. Now, almost four years later, it is interesting to see that these "war babies" were not really such but are well-established enterprises with a bright future. A ten-day trip through the Adirondack region and to St. Lawrence County dispelled all thoughts that mining in northern New York State is a transitory industry. In addition to substan-

Jan 1, 1947

By Joseph A. Sutton, John D. Corrick

The continuing depletion of high-grade ore de- posits in this country has created a need to develop more effective methods for recovering valuable metals from low-grade ores. The use of microorganisms for their biochemical reactions is one possible way to solve certain phases of this problem. Bacteria have been used successfully by many diversified industries. Until recently, however, little attention has been focused on the use of bacteria in mining and metallurgical processes. This report summarizes one phase of the microbial studies being conducted at the U.S. Bureau of Mines, College Park Metallurgy Research Center. The two-fold objective of this study was, first, to determine if pure strains of the bacteria Ferrobacillus ferrooxidans, Thiobacillus concretivorus and Thiobacillus ferrooxidans could utilize the iron and sulfur occurring in sulfide minerals to produce appreciable quantities of ferric sulfate and sulfuric acid for dissolving copper and, second, to develop the chemistry involved in the microbial oxidation of sulfide minerals. These are of particular interest as they relate directly to the feasibility of employing microorganisms in leaching operations.

Jan 6, 1963

By Thomas M. Plouf

Flotation, as we know it today, is a physiochemical method of concentrating finely ground ores. The process involves chemical treatment of an ore pulp to create conditions favorable for the attachment of certain mineral particles to air bubbles which are carried to the surface of the ore pulp for removal. Frother reagents, combined with air and the agitation mechanism, produce the effective bubbles in a flotation cell. A method of analysis is presented to evaluate the effect of frother reductions and additions on a bank of flotation cells, and to economically determine if and to what extent frother reductions and additions are justified. Comparative evaluations of different frother systems, as well as the amount of frother used in a given flotation machine, cannot be made on the frother cost alone. An indepth study must be made to evaluate any given frother as applied to a particular ore body. The recovery of a given mineral is as dependent on the amount of frother as on the type of frother used. An actual case study follows in which the amount of frother required by two different flotation machines was used to make a decision as to which unit performed more efficiently based on costs. This same method may be used to evaluate new frothers as well as to determine if a larger frother addition is advisable.

Jan 11, 1975

By Arthur Knapp

The economics of fuel oil must be considered in two aspects; viz., fuel oil as one of a number of competitive fuels and fuel oil as a refined product of petroleum. "Fuel oil" is usually defined as that product of petroleum which is used in furnaces for the generation of heat by simple combustion. It is true that any product of petroleum used in an internal combustion engine is essentially a fuel oil, but such oils are not included in the class known as "fuel oil." Fuel Oil as One of Several Fuels For a number of years, the petroleum industry has believed that the petroleum reserves were very limited and that petroleum products would begin to become scarce within a few years. The industry has believed that there would be a gradual but continual rise in prices as a result of this impending scarcity. The industry, therefore, has informed the users of fuel oil thai., once they were eliminated by price, they were eliminated for all time. The petroleum industry believed and made the consumer believe that there would never be any appreciable recession in price which would make it

Jan 1, 1928

By Frank W. Reinmiller, Edward S. Hsia

Earth bottom thickeners are generally considered to be the lowest cost solution for thickener bottom construction presently available to the mining industry. In addition to the capital cost advantage, these basins have proven to be watertight structures providing trouble-free operation for indefinite periods of time. During the past 15 years, some 18 of these thickeners have entered service with no particular problems encountered in porphyry copper operations, counter-current decantation in a gold cyanide plant, and other similar applications in mineral processing. In the course of this work, technological advances have been realized in the procedures for engineering and construction of these units to assure watertight basins and achieve all possible economies in construction.

Jan 8, 1977

By Irving Fatt, R. M. Weinbrandt

Efforts have been made for many years to observe pore structure of sedimentary rocks on a microscopic scale. A better description of the pore structure in reservoir rock would aid in the development of relations between flow through tube network models and flow in consolidated reservoir rock. The unique qualities of the scanning electron miscroscope (SEM) make it the ideal tool to use in a study of pore structure. Previous methods of studying pore structure included plastic casts of pore space and optical microscopy.l-7 There is now available a new method to observe three-dimensional flow channels in reservoir rock: a scanning electron microscope having variable magnification from X20 to X20,000 and approximately 1000 times the depth of focus of the conventional light microscopes. This microscope also can obtain stereoscopic images and can measure and diagram flow channels so that it is possible to construct a network of tubes that will model consolidated reservoir rock. THEORY OF THE SCANNING ELECTRON MICROSCOPE The scanning electron microscope (SEM) functions by projecting a beam of electrons through magnetic focusing lenses at a specimen and recording secondary electrons excited by the primary beam. The amount of secondary electron emission portrays the topography of the specimen because more secondary electrons are emitted from high points than from low points. A schematic of the SEM is shown in Fig. 1. The property of the SEM that is of most importance in this study is its great depth of focus. The depth of focus results from using electrons

Jan 1, 1970

By J. Wes Blakely

In the mid-1950s the importation of foreign oil began to encroach on traditional coal markets such as railroad steam engine fuel, home heating, electrical generating plants, and others. Many of the smaller coal companies with substantial coal reserves subsequently found that they could no longer continue to mine economically and merged in various ways with larger established coal mining concerns. As the seats of top management and authority were removed from the mines to large metro centers such as New York, Pittsburgh, and Chicago, the more personal relationship between mine workers and management that had existed prior to these mergers began to be eroded and replaced by 'remote control mine management. The disappearance of this face-to-face contact of upper management with mine employees tended to create barriers blocking simple effective communications between coal mine management and labor. In examining the human relations aspects of the coal mining industry, many elements, some concerned with work and others not, have depicted the industry as almost devoid of good applied human relations and communications practices, and, in truth, little has been done to alleviate this situation . In past years many coal producing companies, with the exception of one of the largest, failed to adequately define the term “communications” as it applied to their companies, whether internally or externally. Internally many still place heavy reliance on written communications such as company-wide newspapers to do the job of communicating with their employees which they feel ought to be done. One company puts an inordinate belief in its company "newspaper" as the primary instrument to stimulate its work force into increasing productivity. Primarily aimed at the workers, who greatly outnumber the salaried administrative people, this publication mainly documents the fortunes of individual mine workers who are felt to have achieved something with their lives, e.g., a mine worker who had managed to put four children through universities, the

Jan 1, 1981

Meeting, Aug. 20, 1913, B te, Montana, at 12.45 p.m.-On, the written request of 27 members of oft Institute residing in Montana, the Montana Local Section was established, and the following Committee was appointed by the President of the Institute to complete the organization : E. P. Mathewson, Chair pan; Frank M. Smith, Vice-Chairman; D. C. Bard, Secre-tary, Montana State School of Mines, Butte, Mont., Oscar Rohn, James L. Bruce. The President reported the appointment of a Committee on Mining Law, the names of whose officers and members are given on page xxxv of this Bulletin, and these appointments were approved. It was voted: That the Committee on dining Law be requested to establish a Sub-Committee on Censorship, a majority of whom shall be lawyers; and, further, that no paper on mining law be recommended for publication to the Committee on Papers and Publications, unless it is previously approved by the Sub-Committee on Censorship of the Committee on Mining Law. The President reported progress in the matter of co-operation between the Institute and the United States Bureau of Mines, through Committees of the Institute. The President reviewed the history of plans for a union or affiliation with the Mining and Metallurgical Society of America, and the following minute was then adopted : " The Board of Directors of the American Institute of Mining Engineers has carefully considered for several months the question of union or affiliation with the Mining and Metallurgical Society of America ; and, while at an earlier time and under other circumstances, such. a union might have been accomplished, yet under present circumstances the Directors of the Institute deem such union inexpedient. "While thanking the Mining and Metallurgical Society of America for its consideration of the matter, we believe that further discussion of the subject will serve no useful end, and we conclude it best that the Society and the Institute continue their useful functions and friendly relations side by side, as heretofore."

Jan 10, 1913

By L. G. Huntley

Points out differences between the new, more liberal, law passed by the Colombian Congress and the law passed in 1919, gives a few facts about the pipe-line concession granted to a Canadian company, and tells of new drilling developments. PROBABLY the most important development in the Colombian oil situation during the past year was the passage by Congress of a new petroleum law, which went into effect Jan. 31, 1923. The principal points of interest in which this new law changes or improves the previous one are as follows: Law 120 of 1919 provided that one person or corporation could not acquire more than three exploitation zones. of 5000 ha. each, and royalties were based on a sliding scale, to wit: 6 per cent. royalty on lands 400 km., or more, from the ocean; 8 per cent. on lands 200 but not over 400 km. from the ocean, and 10 per cent. royalty on lands located less than 200 km. from the ocean. Rentals were fixed at 10 centavos per hectare for the first year; 20 centavos for the second year; 50 centavos, third year, and $1 (one peso) yearly thereafter. Under this law the term of the lease was fixed at 20 years and, at the discretion of the government, could be extended for 10 years additional. After the expiration of the lease and its corresponding extension, the machinery and other material placed upon the property would vest in the government. A bond of 20,000 pesos was also required of the lessee to guarantee faithful performance of his contract.

Jan 3, 1924