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By F. S. McNicholas

IN the first big blast at Climax, a "loop back" (three-wire system) was used (Fig. 1), with the idea of securing a wiring system that would give to all series the same amount of current. Single-phase, 60-cycle, 13,800-volt FIG. 1.-Loop BACK. A THREE-WIRE SYSTEM WITH BRANCHES VARYING IN LENGTH. power was furnished to the blasting transformers, each of which has a rated capacity of 600 amp. at 480 volts. Two blasting leads were taken from these transformers, giving a blasting current of single phase, 60 cycle, 480 volts, with an instantaneous capacity of more than 600 amp. The blasting switch was on the secondary leads from the transformers, to avoid lag in energizing them.

Jan 1, 1938

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 Arthur E. Granger

IN the early days of the science, and until the recent past, geologists worked as individuals or in small groups. Prior to 1930 perhaps the largest single group under one administrative head was the Geologic Branch (now Division) of the U. S. Geological Survey, which employed at that time (including temporary help) 100 to 150 geologists. Today that same unit employs some 1500. In industry some companies employ as many as 100 geologists in a single department. These numbers obviously pose a need for administration. The basic qualifications for good administration are the same for any group of human beings, but the administration of geologists presents some special problems. Choosing Administrative Personnel: There are two kinds of personnel needs: 1) technical, which requires professional geologists who have proved their capabilities in the field, and 2) clerical and fiscal, which provide the necessary supporting or housekeeping functions. This discussion will be concerned only with the first category, except to point out the need for competent and understanding help from clerical and fiscal people and close relationship between top administration, technical or professional personnel, and the clerical and fiscal groups.

Jan 7, 1957

By John V. Beall

One Sunday night last month the phone rang and it was George Schenck from Penn State. How would we like to see a big scrap operation, he wanted to know. A few days later we were on the Connecticut turnpike headed for New Haven to visit a large scrap operation, M. Schiavone and Sons. George had a large clam basket in the back which he explained was for collecting trophies. The car shredder, he said, turns out some fancy metal shapes. In fact, they have gained a certain acceptance as objets d’art among George's friends and relatives. He thinks there may be a small, but possibly lucrative secondary market for shredded cars in the art world if the idea is imaginatively promoted. On the way to New Haven we received a briefing on the scrap industry. The scrap business grew from humble beginnings. Mostly it was started by a few immigrant Jews who collected junk in hand- or horse-drawn carts. The fortunate one might even have had a truck. Before proceeding further, we hasten to point out that the word "junk" is strictly taboo among scrap people, who prefer to refer to their industry as the "secondary metals industry."

Jan 1, 1970

By William N. Wallinger

The mine and concentrator of Cyprus Anvil Mining Corporation are located in the south central section of Canada's Yukon Territory. The Yukon is sparsely settled, with a total population of less than 23 000. Wide seasonal temperature variations are experienced with extremes of 35º C and -57º C being recorded at Faro. The concentrator treats 9000 tons per day of a complex lead-zinc sulphide ore, employing conventional crushing, grinding and differential flotation to produce selective lead and zinc concentrates as well as a mixed lead/zinc (bulk) concentrate. The current operating practice and highlights of the eight years the concentrator has been in operation are reviewed. In addition, certain of the unique features and problems connected with plant operation in a remote northern location are discussed in some detail.

Jan 1, 1977

By D. Hodouin, T. Gelpe

A digital simulator of classification and grinding circuits is used to evaluate the performance of various flowsheets. For a given flows he et configuration, unit process dimensions, and operating conditions, the simulator calculates the steady-state values of the process variables and determines the conditions that meet the required operation criteria for tonnage and product quality. Calculation examples are proposed for the design of wet and dry grinding circuits. The performance of different configurations of cement clinker and sulfide ore grinding flowsheets is evaluated and discussed.

Jan 1, 1986

By E. L. Fisk

First discovered and claimed in 1929, the Cordero cinnabar deposit lies 11 road miles southwest of McDermitt, Nev., near the Nevada-Oregon boundary. The name "Cordero" means "little lamb" in the Basque language and is symbolic of the fact that the first ore specimen was found during the lambing season. The Bradley Mining Co. held the property for several years during the early thirties, but it was not until 1939 that Cordero Mining Co., a subsidiary of Sun Oil Co., entered the picture. The company, then known as Horse Heaven Mines, Inc. conducted preliminary work in 1940 which proved enough near-surface ore to warrant the construction of a mill during the following year. By 1943, Cordero was being rapidly depleted when deeper churn drilling intersected the large underground orebody that is still being mined today.

Jan 11, 1961

By Paul A. Hodges

With plant start-up slated for early 1966, Palabora Mining Co. will take its place among the large copper mining properties of the World. Located near the town of Phalaborwa in the Lowveld area of Transvaal Province, approximately 250 air miles northeast of Johannesburg, Palabora is the result of a cooperative project between Rio Tinto-Zinc Corp. and Newmont Mining Co. Other large shareholders are American Metal Climax, Inc., Union Corp. Ltd., and Selection Trust Ltd. Earliest known mining activity in the area is thought to date back about 400 years, when the Bantu tribes were migrating southward from the great lakes of Central Africa. Old workings and hand tools have been found in numerous places on the flanks of Loolekop, the hill that contains the outcrop of the Palabora orebody. Nearby ruins of small furnaces give added evidence of the knowledge of copper smelting possessed by these natives.

Jan 3, 1966

By A. W. Hahn

THE importance, to geologists and metallurgists, of knowing the mineralogical forms in which the silver occurs in ores has increased during the past few years, and will continue to increase as long as working hypotheses are converted into proved theories and rule of thumb methods are supplanted by scientific data. The methods used for the determination of these silver minerals have been: (1) careful study of polished ore sections with the microscope, and more recently, (2) metallurgical separation of the ground ore by flotation, tabling and panning, supplemented by microscopic examination of these separated minerals, and chemical analyses. During the course of some experimental work carried on by the testing department of the International Smelting Co. and myself, it becomes important to determine, in a general way, the distribution of the silver values in the minerals, as they exist in Tintic Standard and North Lilly siliceous oxidized lead-silver ores. These mines are in the East Tintic Mining District, State of Utah. In this work the second method was used. Differential flotation tests were run, separating the sulfide from the oxidized minerals, and the products were assayed. Various concentrates were carefully panned and the separated products assayed; special samples of ore were selected and assayed. The microscope was used only for the purpose of determining whether the individual minerals were in the so-called "free" state.

Jan 1, 1929

By Paul Gordon

It is shown that equations for grain-boundary migrntion given by Gordon and Vandermeer, based on a theory first advanced quantitatively by Lucke and Detert, satisfactorily explain recent data on both GRAIN boundary migration in recrystallization and in postrecrystallization grain growth has been the subject of extensive studies for many years. Only solute-independent and solute-dependent boundary migration during recrystallization in zone-refined, poly crystalline aluminum, and during grain growth in zone-refined tin. with the advent of zone-refining, however, has it been possible to carry out such studies on high-purity metals, and thus to delineate quantitatively the major effect On the migration rates of very small percentages of dissolved imPurities. Earlier exPerimental work almost invariably gave migration rate parameters which disagreed with theoretical predictions

Jan 1, 1963

By John A. Bonucci

AMAX Base Metals R&D, Inc. has developed technology for extracting and recovering platinum and palladium from spent automobile exhaust emission control catalyst. Our most promising route is a chloride-based hydrometallurgical flowsheet in which catalyst pellets or crushed monoliths are leached in HC1 with an oxidant at 95°C without agitation. Alumina co-dissolution can be limited by thermal pre-treatment of the catalyst. The leach solutions are treated by one of several precious metals recovery techniques to produce a high grade PGM concentrate. For the new generation of three-way catalytic converters which contain rhodium, an H2S04 preleach could selectively extract much of the rhodium while leaving the platinum and palladium behind. Capital and operating costs will be discussed.

Jan 1, 1984

By Julian Nardi

Pumping solids through a pipeline is not new but until very recently other means of transportation were cheaper. Many proposed pipelines for transporting solids, while technically feasible, have not been attractive enough to warrant the financial risk involved. In some instances, the difference in transportation cost was negligible. In others, the threat of pipeline competition resulted in a slashing of rates on existing transportation to the point where a pipeline could no longer be justified. In others, a competitive product was cheaper. FIRST IN PLACERS The earliest record of solids being transported in a pipe was in the late 1850s in California placer mines. Water under pressure was used to force gold-bearing gravel up through a pipe, from 30 to as much as 55 ft, to a point where it could be discharged into a flume or sluice.

Jan 9, 1959

By S. Edward Drummond, Charles D. Haynes, Stephen H. Stow

This paper is a preliminary report on the occurrence and distribution of economically interesting heavy minerals (kyanite, sillimanite, staurolite, zircon, monazite, ilmenite, leucoxene, rutile) in sands from the sea floor surface of the offshore area, Alabama-Mississippi. Weight percent of heavies derived from the +60 portion of 97 samples is contoured in [Fig. 1]. Five hundred grains from 42 of the heavy mineral separates were identified and sized microscopically; the data were converted to weight percent for each mineral species and are summarized in [Table 1]. Heavy Mineral Distribution In the Gulf, there is a general westward decrease [(Fig. 1)] in maximum abundance of heavies from 2.4% north of Sand Island at the mouth of Mobile Bay to slightly over 1.0% south of Petit Bois Island and a corresponding decrease in the Mississippi Sound from 1.4%, north of Dauphin Island to slightly over 0.25% north of Horn Island. Average concentrations of heavies for different areas are found in Table 1. There is westerly longshore transport in this area; the interaction of the longshore current with discharge from Mobile Bay and disruptions of the current by Sand Island, possibly aided by a shoaling effect, appear to be the cause of the preferential deposition and concentration of heavies (2.4%) north of Sand Island in 10 to 14 ft of water.

Jan 1, 1977

MONDAY, FEB. 17 9.00 A.M. to 9.00 P.M. Registration at Institute Headquarters. 9.00 A.M. Meeting of Committee on Development of the Activities of the Institute, Room 905, 9th Floor. 10.00 A.M. Simultaneous Sessions of Institute of Metals Division, Room 2, 5th floor. Industrial Organization, Room 1, 5th Floor. 12.30 P.M. Luncheon at Headquarters, 5th Floor. 2.00 P.M. to 4.25 P.M. Simultaneous Sessions of Institute of Metals Division, Room 2, 5th Floor. Industrial Organization, Room 1, 5th Floor. Petroleum and Gas, Room 905, .9th Floor. 2.30 P.M. Sightseeing trip by automobile for the ladies. Among the points visited will be: The American Museum of Natural History. The Episcopal Cathedral of St. John the Devine. The Spanish Museum. The American Geographical Society. The American Numismatic Society. The visits will be followed by Tea. 4.30 P.M. Memorial Service to Dr. Rossiter W. Raymond, Auditorium. 8.30 P.M. Smoker, 5th.floor.

Jan 2, 1919

By I. Ionel Gardescu

During the latter part of 1930 an agreement was reached among operators in Rumania to curtail the production of oil to about 100,000 bbl. per day. This agreement lasted only a few months and 1931 shows a new peak in production with an average yield of 136,900 bbl. per day as against an average of 116,600 bbl. per day for 1930. The total production for 1931 was 49,210,000 bbl.; an increase of 18.4 per cent over the previous year's production. It is interesting to compare the percentage production of the major companies to the potential production figures determined by the Government in September, 1930 (Table l), on the basis of which the proposed curtailment was to have been made. The three companies listed first in this table show an increase in average production for 1931 over their estimated potential production rating. This increase might be attributed at least in part to the recent development of the Boldesti field, which is controlled by these companies and of which the production at present is nearly 10 per cent of the total oil output for Rumania. Among the other fields, Moreni still holds first place with an output of 33.6 per cent, followed by Gura-Ocnitzei with 29.3 per cent. In both these fields the main source of oil is from the deeper Meotic sands. Other

Jan 1, 1932

By S. C. Oliphant, George H. Fancher

Two samples of drilling mud from the Hastings oil field, Texas, were tested, and the solids in each were separated into small fractions of a limited range in particle size. The mineral composition of each fraction by X-ray analysis is reported, and the results are interpreted in relation to other measured quantities, such as the physical properties of the original samples and the density of the various fractions. It was found that only 7 to 8 per cent by weight of the solids was of colloidal dimensions and that neither of the samples contained montmorillonite but did contain illite. Considerable calcite was also found. These data should be useful to the geologist interested in the origin and history of sedimentary strata as well as to the petroleum engineer.

Jan 1, 1942

By Robert A. Haney, Stephen J. Gigliotti, James L. Banfield

A series of investigations were made by the Mine Safety and Health Administration to evaluate the performance of various face ventilation systems as part of a program to reduce frictional ignitions of methane and to develop face ventilation systems that could be used with the line brattice more than 10 feet from the face. Tests were conducted in a full-scale laboratory model of a face area. Systems tested included unassisted blowing and exhaust line brattice, diffuser fan and spray fan systems. Systems were evaluated at air quantities ranging from 1.4 to 7.0 m3/s (3,000 to 15,000 cfm), and brattice-to-face distances from 1.5 to 9 meters (5 to 30 feet.). Tests were designed so that systems could be evaluated for the location of the high-point methane concentration in the face area, methane dilution capacity, and face ventilation index. The methane dilution capacity is the total amount of methane a system can dilute to 1.0 volume-percent. The face ventilation index is the efficiency at which the available face air volume is being used.

Jan 1, 1982

By G. Kinder, R. Gilges, W. Stoker, R. Davey

The Bingham Canyon Mine, located 48 km (30 mi) southwest of Salt Lake City, Utah, is operated by Kennecott Copper Corporation's Utah Copper Division. This operation is the world's largest open-pit copper mine and produces 96 000 tons (106,000 st) ore and 327 000 tons (360,000 st) waste each day. This material is loaded by large electric shovels and transported by both truck and rail haulage. To meet the requirements of the Clean Air Act of 1970 (as amended), new facilities for the control of smelter emissions were required and are now nearing the final stages of construction. The facility will be capable of treating all the output from the mine, some 2,530 tons (2,789 st) per day of combined concentrate and precipitate. Costing $280 million and necessitating the replacement of reverberatory furnaces with continuous smelting vessels, the plant, with its massive and complex gas handling and acid-making facility, is required to remain on-stream with the minimum of pollution control equipment outages to conform with Federal Regulation 52.2325.

Jan 8, 1978

By I. Stapf

Systematic investigations on silver-rare earth metal systems have been extended on the Ag-Ce system in order to clarify the discrepancies reported in literature. The phase diagram has been reinvestigated on the base of thermal analyses and of microstructure examination on cast and annealed specimen. All intermetallic phases Ag4Ce, Ag3Ce, Ag2Ce and AgCe show no extended range of homogeneity, they melt congruently fm), or decompose peritectically (d) at 815 °C (d), 1030 °C (m), 855 °C (d) and 855 °C (m), respectively. The system shows eutectics at 793 °C/10 at.%, 780 °C/42 at.%, and about 505 °C/81 at.% Ce. d-Ce dissolves up to 2 at .% Ag and decomposes metatectically at 710 °C. Furthermore, the phase transformation of the intermetallics would be clarified. The phases Ag5Ce and Ag51Ce14 reported in literature could not be verified.

Jan 1, 1984

By Gene Long

10.4-1. Load Design and Construction. Surface mine haulage roads are used for transporting raw products to the mine site, preparation plant, or loading facilities, and to provide personnel and equipment an access to the pits and mine area. All of the aspects of highway engineering, including minimum slope inclines, properly banked curves, and adequate drainage, must be followed to facilitate construction of safe and efficient haulage roads for fast and economical transportation of the mined product to its destination. By maintaining good haulage roads, both truck and equipment maintenance will be kept to a minimum, resulting in reduced mining costs and subsequently higher profits. [ ] There are several basic considerations in haulage road planning. Most important, one must follow all safety procedures in both design and construction of the roadway. A maximum effort should be made to follow current mining plans when laying out and planning haulage roads (aerial photographs can be extremely useful in planning and routing of roadways). Grades, road widths, and curves must be maintained within limits of present and/or planned haulage equipment specifications, since all these factors can limit speed, and hence production (Table 10.4-1). Grades in most mining operations are adverse (against the loaded haul), which increases haul cost per mile. Operators must balance these increased

Jan 1, 1968