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By John V. Beall

Spots Goblenski fluffed up his pork chop sideburns, checked the angle of his wide brim Stetson and ambled off the airplane. The pert Braniff hostess stood smartly at the door. "Goodbye now, take care," she said in the special airline stewardess voice superimposed on a Texas drawl. Spots smirked, "You betcha, Peaches, you too." It was a crystal clear, sunny day which New York can have at any season of the year (but rarely gets credit for) and being in high spirits Spots did not mind being captured by a cab driver. That is the cab driver brushed aside all other conversation to give a continuous colorful commentary on New York politics, revealing in the process that only the very wealthy and cab drivers share the same political views in that city. After installing himself in the fading opulence of the Hotel Roosevelt, he finished the day with a steak dinner with baked potato under sour cream and hearts of lettuce salad with Roquefort dressing at the Black Angus restaurant. The next morning he had an appointment with Hemphill, Frye and Louderdock. The offices of this prestigious firm of management consultants are high in the Pan Am Building. He was courteously received by a lacquered receptionist and was soon escorted into the presence of Mr. John Smith. "Ah, Mr. Goblenski; Spots, isn't it? Hope you had a good flight. Lovely weather we are having. Just make yourself comfortable over there, Spots." Smith seemed cordial and Spots slipped comfortably into the interview. He had always thought that management consultants were evolved from the "efficiency experts" made famous by the radio team, Amos and Andy. He associated the modern version with computers, PERT and other systems approaches. He was surprised that one of these firms was apparently acting as an employment agency. "Of course" continued Smith, "in evaluation of basic criteria of performance moduli, the human element enters, Spots, and that brings us to you." Spots sat up and focused his attention.

Jan 1, 1970

By Rudolf Kudlich

THE problem of eliminating the hazards of hoisting in mines has been with us since the industry passed its earliest stages, when coal and ore could be won from surface working and tunnels. At first, safety devices were introduced as means of decreasing the amount of labor necessary, to produce the mineral, or to increase the amount that could be obtained from a certain opening. For example, crude, ladders replaced winding footpaths or steps cut into the walls of the pit or shaft, decreasing the distance it was necessary to carry the product to the surface and eliminating, to some extent, the hazard introduced by the precarious footing afforded by such paths and steps. Later, instead of being carried from the pit on the backs of men, the product was hoisted in buckets or baskets on a rope passing over a pulley or around a windlass. Thus the capacity of the pit was considerably increased, and the hazard due to making many trips up and down the shaft was eliminated. From such beginnings accident prevention in mine hoisting advanced with the importance of the industry, until at present hoisting compares favorably with other branches of the mining industry with reference to safe practices. As in the other branches, this progress has been accomplished along two general lines-by legislation, rules, and education, and by the installation of safety devices. Though due credit must be given the former, it is not so satisfactory as the latter. Legislation, to be effective, requires a policing and inspection system to guarantee enforcement, such as we cannot hope to inaugurate. Rules may be satisfactory so long as the employer controls the labor market, and dismissal or some other form of discipline is an effective means of insuring obedience to the rules; but where labor demand is in excess of the supply, or where labor organizations are in control, such measures are not effective. An educational campaign will draw attention to hazards and may awaken a desire to avoid accidents by exercising the proper care.

Jan 2, 1922

This study of engineering education arose out of the action of a joint committee on engineering education, representing the principal engineering societies. The committee had gathered so much material that it decided the work could best be carried out by some one trained in applied' science, who would devote his entire attention to the study.. The Carnegie Foundation therefore asked Prof. Charles R. Mann, of the University of Chicago, to undertake the work. After making a thorough study Prof. Mann has made a most comprehensive report. In it he says: The engineering schools of the United States began their work upon a definite teaching plan and one that had at least pedagogic consistency. But during the past half century the course of study has been overlaid with many special studies intended to enable the student to deal with the constantly growing applications of science to the industries. As a result, the load upon the student has become so heavy that there is a feeling that the students fail to gain a satisfactory grounding in the fundamental sciences and do not fulfil the expectations of engineers in d manufacturers in dealing with the practical problems with which they are confronted on leaving school. At present 60 per cent. of those who enter the schools fail to graduate, still many of them persist in engineering and make a success of it. It is evident, therefore, that the present systems of admission are not satisfactory. If a group of schools will take up the careful study of their entrance systems and experiment with objective tests and records of the students' youthful interests and achievements, the percentage of elimination can be reduced to at least a fourth of its present size, with an enormous saving of time, energy, and money for both student and school. The number of required credit hours per week should be less than eighteen, preferably sixteen. The few experiments that have been made indicate that college students do their best work when not more than five subjects are studied at a given time.

Jan 1, 1919

By M. S. Tsai

Recovery of uranium from wet-process phosphoric acid is a newly developed source of uranium. Many processes have been developed but the OPAP (octylphenyl acid phosphate) process is still the valuable one because the OPAP reagent compound has the high extraction ,power and cheap cost. The OPAP process was already studied by murthy(1) in 1970 and its complete process flow sheet was first fulfilled by F.T. Hurst(2) in 1974. WCFC(3) (western Co-op Fertilizer Ltd.) in cooperation with ESI (Earth Science Inc.) set up the OPAP uranium recovery pilot plant in Canada in 1978. We have studied the OPAP process since 1974 and first improved the OPAP extractant by proper adjustment of the DOPAP/MOPAP mole ratio with CH3OH-H20 method, resulting in shortening the phase separation time and avoiding the precipitation occurrence in our process. Second, we utilize the reduction and oxidation occurring by DC power supply on either side of the membrane to achieve the extraction and stripping at the same time. An improved OPAP process in which high recovery yield of uranium and acid uncontaminated by iron has been developed in our laboratory.

Jan 1, 1982

By D. Harrington

Most of those in the Health and Safety Branch, Bureau of Mines, necessarily participate in activities associated with essentially all phases of the mineral industries, including coal and noncoal mines, quarries, smelters, metallurgical plants, and various petroleum operations. One of the strictly war activities of the branch - the Explosives Control Division, which administers the Federal Explosives Act of December 26, 1941 - has functions that require contacts not only with nearly all phases of the mining and allied industries but also with those engaged in scores of other occupations that manufacture, store, use, or possess explosives, or many of the ingredients of explosives. The field men of the Health and Safety Branch (approximately 300 in number) Are occupied full time in health and safety activities and annually make thousands of contacts with people in the mineral industries as well as the plants in which they work. From these they formulate several thousand written reports containing sources of thousands of conclusions and recommendations aimed at reduction of health end safety hazards in these industries. Although such activities have been greatly increased during the war and immediate pro-war periods, they have been in effect to a considerable extent since the Bureau of Mines was created in 1910.

Jan 1, 1944

By Arnold O. Tanner

The domestic mining industry continued to be strengthened and revitalized in 1989. The healthy conditions and the industry comeback that began in 1987 continued to spread and became more established for many commodities. Relatively comfortable and stable commodity prices, still found predominantly in the metals sector, reinforced other operational factors in bringing vitality to the mining and mineral processing industries. New streamlined business practices, mine and plant modernizations, and the progressive use of new technologies successfully helped lower operating costs and increase efficiency during the past 5 to 7 years. An element common to these three factors of industry renewal and growth was the ever-increasing infusion of and growing dependence on constantly advancing computer technology applications. This trend of increasing computerization was occurring throughout the mining and mineral processing business while it similarly was in most facets of modern business and culture. Some commodities and companies still struggled to outlive sluggish prices and other unstable market conditions or to modernize their businesses, but increases in productivity and profits were more common. A trend toward increased mechanical excavation in nonsoil materials was beginning to surface as a substitute for standard cyclic mine development techniques, such as drill-and-blast and surface shovel-and-truck routines. More continuous mechanical excavation offered the potential for increased production, fewer people at the working face, better ground control, and generally improved safety. The main limitation was rock hardness. The construction industry had already recognized the benefits of tunnel-boring machines for long underground drives and mechanical planers for pavement removal. The Colorado School of Mines held a short course during the year entitled, "Mechanical Excavation Techniques in Mine Development and Production,'" which was at-tended by nearly 100 engineers from 12 countries. The consensus of attendees was that for the most efficient use of these machines and techniques, new mining plans needed to be developed beyond the simple adaptation of those excavators to existing mine plans.1

Jan 1, 1991

By A. H. Lindley, Fraizer M. Stewart

For many years large mining companies were able to finance nearly all of their capital requirements from internally generated funds. However, during the last decade, funds needed for capital expenditures, dividends, and scheduled debt retirement have grown faster than cash flow. As a result the minerals industry has had to rely increasingly on other sources of funds. Getting the capital for new mining projects is a challenge, particularly for smaller companies. New methods of financing and new variations to old methods have been developed and more are needed. Commercial banks are short-term lenders. By policy their loans are limited to low risk loans-those made solely on the borrower's general credit, and secured loans where cash flow is sufficient to provide repayment within a comparatively short term. To maintain liquidity, banks prefer to make loans of less than seven years' term. If a longer loan is needed an insurance company or pension trust may take the long-term part.

Jan 1, 1971

By V. Shchukin

According to the scientific views formed by the middle of nineteen seventies there should be no possibility of commercial diamondiferous kimberlites in the north of the west European platform. However a later analysis of the geological data gave rise to the concept that diamond bearing kimberlites would be present in the north but on the mineralogical level they would differ from kimberlites of South Africa and Yakutia. Further investigations resulted in the confirmation of these conclusions and with discovery at the beginning of 1980 of diamond bearing kimberlite pipes in the Arkhangelsk region.

Jan 1, 1995

By B. Madelin

Over the last ten years, Minemet Recherche and Metaleurop have used an approach in order to investigate and improve the operation of its Smelting furnace and its lead blast furnaces. This approach gives importance- to three complementary means of investigation : - Probing campains in the industrial furnace (temperature and gas analysis profiles), - Chemical and physical modeling (coke combustion, sinter reduction modes, flows patterns, ?.) , - Staged mass and heat balances or kinetic model. This allows to define the limits of operation of each blast furnace and to predict the influence of operating parameters on the furnace performances. For the zinc Imperial smelting furnace, the probing results show the existence- of both an Isothermal reserve zone at 1015ºc and a chemical equilibrium between ZnO and gas which makes possible the use of a practical model for heat and material balances. In particular, very good prediction on the influences of operating parameters can be made. On the contrary, for lead blast furnaces, the probing results show that the thermal and chemical equilibria are not reached. Consequently, classical models for staged heat and mass balances are not sufficient. The use of the other means allows then to characterize the specific influences of operating parameters on the thermal instabilities of these furnaces and their allowed limits.

Jan 1, 1990

Industrial minerals enjoyed a fairly successful year in 1978, despite the sluggish economy, inflation, and environmental restrictions. A glance at US Bureau of Mines statistics shows that, in general, production of industrial minerals increased from + 1% (salt) to as much as 26% (sulfur, other than Frasch or recovered). A few industrial minerals showed a decline; fluorspar production, for example, registered a 23% decrease in 1978 from 1977 due to the closing of three domestic mines. Bromine, natural sodium sulfate, Frasch sulfur, and vermiculite also had production decreases of 2-6% in 1978.

Jan 5, 1979

By A. F. Baker

The Bureau of Mines conducted pressure-drop studies in a 4-foot-diameter simulated blast furnace shaft to compare anthracite metallurgical briquets with coke and formcoke. The test materials were used alone, layered, and in mixed burdens of commercial fuel-to-ore ratios. Anthracite briquets had a higher pressure drop per foot than furnace coke, but they had a lower pressure drop per foot than formcoke. This appears to be due to packing and shape, as well as to particle size. The superficial air velocities at which beds of briquets and furnace coke disrupted were about the same. However, if briquets of the shapes and sizes tested are substituted for furnace coke in commercial metallurgical furnaces, higher blowing pressures will be required to deliver comparable amounts of air. Test burdens with more than 5 percent material smaller than 1/4-inch diameter showed significant increases in resistance to airflow.

Jan 1, 1967

By N. Kuroda

A realistic simulation model has been used for designing longwall mining, especially for solving operational problems. This paper describes background, development, validation and some applications of the simulation model for mining people who are unfamiliar with O.R. or computer technique, as a simple planning tool. The following items were established: logical analysis and algorithmic design for practical longwall mining, structure of hypothesis behavioral organism, input parameters, using practical knowledge and operational statistics of the mechanized longwall system experienced for many years.

Jan 1, 1982

By Louis A. Panek

Using an approach based on the theory of similitude, the author develops a general equation and related concepts that provide new insights to an old problem. The load-bearing capacity (strength) of a square, rectangular, or cylindrical prism of a brittle material such as rock, coal, or concrete is expressed as the mathematical product of a size effect, a shape effect, and a function of the mechanical properties (deformability, cleat/joint spacing, and friction) of the pillar, roof and floor materials. Through an application of multivariate statistical analysis, the results of assorted tests and observations of failed pillars can be combined into a fundamental scaling equation, which provides a unified, consistent approach to the estimation of mine pillar strength. The form of the equation is sufficiently general to be able to incorporate refinements in the characterization of the basis factors, as they become available through future experimentation and analysis.

Jan 1, 1979

By S. Lu

The particle-bubble attachment and the rupture of formed aggregates in flotation cell were investigated in terms of turbulent regime. It was found that the particle-bubble collision rate is closely correlated to the energy barrier between particles and bubbles, and no adhesion takes place for the hydrophilic particle-bubble system due to the introduced ?capture efficiency? f(a) being zero. The values of an especially defined Weber number, i.e. the ratios of turbulent stress to aggregate strength in the inertial subrange of turbulence were estimated, the results showed that the detachment of a particle from a bubble involved in an aggregate is mainly caused by the turbulent stress only in the impeller zone, no bubble splitting occurs both in the impeller zone and in the bulk zone.

Jan 1, 1993

By Derek J. McCracken, William G. Holroyd

Emery is a rock that at one time held a large share of the abrasives market. The introduction of synthetic abrasives, however has forced it to settle for only certain niches in the marketplace. This loss of market share is due mainly to the higher amounts of impurities and weaker internal structure that naturally occurring minerals have compared to manmade materials. The use of rocks and minerals as abrasives dates back to early man, who used flint, quartz, and other natural materials to fabricate various tools. During the 19th century, with the Industrial Revolution imminent, the character of the abrasives industry was changed forever as synthetics were introduced. Frank B. Norton is credited with producing the first manmade abrasive when, in 1855, he manufactured a vitrified grinding wheel using emery grit and clay. Before Norton's accomplishment emery had been the only commercially available abrasive. The latter part of the 20th century has seen synthetics capture an increasing share of the abrasives market from natural materials. The term emery is believed to have been derived from the words emeri (French), smeriglio (Italian), and smiris (Greek). The term corundum, for the principal mineral of emery, seems to have originated from kauruntaka, the Indian name for the mineral. GEOLOGY Emery is a gray to black, granular rock comprised of various minerals including corundum (A1,0,), an iron-bearing mineral (usually magnetite-Fe,O,, hematite-Fe,O,, or hercynite- FeAI,O,), and several trace impurities such as mullite, titania, silica, and magnesia. The hardness of emery normally ranges between 7 and 9 on the Mohs scale, depending on its mineral com- position and level of impurities. Corundum, the hardest mineral in emery, typically has a hardness of 9. The specific gravity of emery ranges from 3.2 to 4.5, also depending on mineral composition and purity. The crystallography of each mineral contained in emery differs somewhat. Corundum exhibits an hexagonal crystal structure, whereas magnetite forms within the isometric system, frequently as octahedral crystals. Hercynite, an iron spinel, is also isometric. Hematite has an hexagonal structure but often is found as botryoidal and reniform masses. Principal deposits of commerical emery are found in the United States, Turkey, and Greece. In the United States two emery producers in the Westchester County-Peekskill area and one in the Cortlandt County area of New York closed their mines in the late 1980s. Commercial production in the United States now comes only from the western Cascade Range in Oregon. The emery in New York has a typical A1,0, content of 41.5%. Most of the rock is not true emery because it contains a mixture of spinel and magnetite but very little corundum. The deposits are of Late Ordovician-Early Silurian age and consist of veins in which emery is mixed with olivine, pyroxene, and hornblende. The veins evidently were formed by contact metamorphism and are surrounded by Precambrian schists that contain mica, sillimanite, cordierite, garnet, and quartz. The deposits in Oregon were formed during Miocene time by the contact metamorphism of ferrunginous bauxite by intrusive lamprophyric dikes and plugs. Emery is found in thin layers bordering these tabular dikes, which are usually oriented perpendicular to bedding, and in "surficial placer deposits. The emery deposits in Turkey occur as small, massive, lens- shaped bodies and as surficial placers. They are believed to have formed during Permian and Triassic times. In Greece the principal site of emery production is at Cape Emeri on the Island of Naxos. These deposits consist of lenticular masses of emery surrounded by marble. They originated during Mesozoic time, evidently by metasomatic replacement. Smaller deposits on several other Aegean islands were formed by the metamorphism of bauxite or other alumina-rich materials.

Jan 1, 1994

By W. C. McLaughlin

Under a cooperative agreement, the Bureau of Mines, Magma Copper Co., and ASARCO, Inc., tested backfilled ground support systems at t.wo elevations in Magma's San Manuel, AZ, mine. The tests were mainly for guidance in designing the loading crosscuts of the new ASARCO Sacaton underground mine. Two-piece, wide-flange steel sets for 8-by 8-ft (2.44-by 2.44-m) and 11-by II-ft (3.36-by 3.36-m) openings were designed. Set spacing was 3 ft (0.91 m) and 5 ft (1.52 m), respectively. After erection, the sets were lagged with various test materials. The void between the lining and the ground was backfilled with sand and pea gravel. Instruments measuring strain (used to determine changes in stress) were placed beneath the sets and in the backfill. Results indicate the backfilled sets in the smaller drift (2315 grizzly level, panels 6 and 7) of 8-by 8-ft (2.44-by 2.44-m) cross section are a viable permanent support system, lower in cost than the standard formed concrete. Results are inconclusive in 2615 grizzly level, panels 5 and 6, where wide-flange steel sets were used with 5-ft (1.52-m) long concrete gob lagging of T-design.

Jan 1, 1983

By N. A. Abdel-Khalek

An experimental study was carried out to compare the results of laboratory column flotation versus conventional flotation for the cleaning of fine coals of different rank and their oxidized samples as well as discrete size fractions. Surface oxidation caused a significant reduction in the flotation yields achieved with both methods. However, the column flotation produced concentrates? of lower ash content. The recovery -size curve achieved with column was similar in shape to that obtained with conventional cell, with superior results in the region of fine fractions. The influence of some column operating parameters was also discussed.

Jan 1, 1990

By Guilliaem Aertsen

The derivation of the word tire (or tyre, as it is spelled in England) is obscure. Some dictionaries suggest that it is the aphetic form for "attire, covering," so called as being the outside covering or band of a wheel; also as a corruption of "tier," the band which holds, or "ties," the rest of the wheel together. One dictionary states: "The supposed derivation of the word is that bands were first used on wheels in the City of Tyre, Syria." In the infancy of railroads, the tracks consisted of flat bars of iron, spiked or bolted to the upper surfaces of longitudinal timbers, which, in turn, rested upon masonry foundations. Stone blocks installed for this purpose on the old Germantown & Norristown Railroad, now the Chestnut Hill branch of the Philadelphia & Reading Railway, were to be seen for many years on the right-of-way, north of what is now Wayne Junction, Philadelphia, Pa. The "cornerstone" of the Baltimore & Ohio Railroad was laid Apr. 4, 1828, and the fist locomotive in America was built by Peter Cooper at the St. Clair Works, Baltimore, Md., in 1829 "to demonstrate its adaptability to a curved road." It is believed that the first successful locomotive was built in Philadelphia by Tyler & Baldwin in 1832 for the Germantown & Norristown Railroad. Rufus Tyler and Matthias Baldwin were brothers-in-law; the latter's name will be identified with American locomotives until locomotives are forgotten. The wheels on these first locomotives, designed to run on this primitive rail, mere shod with plain iron bands, bent and welded. The flanges consisted of separate iron bands, bent sidewise,welded, and bolted to the sides of the wooden fellies, or rims. Before many years had elapsed the tires were fabricated of iron bands, rolled in one piece with the flange projection on the side. The tire for each wheel was bent and welded and subsequently attached to the wheel center by shrinkage, bolts, rivets and various mechanical devices. Germany is generally given the credit for first making such tires of

Jan 1, 1917

By FREDERICK LAISY

A NUMBER of new plants for the treatment of copper ores were completed or under construction during the year. Among these may be mentioned the plants of the International Nickel Co., those of the Hudson Bay Mining and Smelting Co. and of the Roan Antelope Copper Co. Three copper re- fineries have been constructed, one at El Paso, Tex., and the other two in Canada. Two more are projected, one in France and one in England. The International Nickel Co.'s plant consists of an 8000-ton concentrator and a smelting plant containing thirty 10-hearth Herreshoff roasting furnaces, five reverberatory furnaces, and eight Smith-Pierce converter5 . The smelting plant is estimated to have a capacity of 5000 tons of ore or concentrate per day. The roasters are superimposed on the reverbratory furnace plant. As a consequence of this arrangement, the furnace building is unusually high. being 183 ft. from yard level to highest roof elevation.

Jan 1, 1931

By John R. Turney

The success of the Mclaughlin acid pressure oxidatiun process has proved that a complex hydrometallurgical process can be an economically viable means of treating refractory gold ores. Homestake's Mclaughin acid pressure oxidation process was commissioned in August 1985 and ts currently operating at design tonnage of 3,000 tons per day. Mineralogical and process studies on the operating plant are discussed to show the improved understanding: of the process and its future applications. These studies are also compared with the initial process development work, thus illustrating the success of the initial scale up considerations.

Jan 1, 1989