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By William H. King

The property of the Cupric Mines Co. is situated in the San Francisco mining district, Beaver County, Utah, 21 miles westerly from Milford (fig. 1), the rail and supply center for the area. Scheelite mineralization was not discovered until 1941, although the occurrence of lead and copper minerals had been known previously. S. VI. Hobbs, of the Federal Geological Survey, examined the Cupric property in November 1941 and prepared topographic and geologic maps of the area. This work was supplemented by additional investigations in January 1943 and March 1944 (fig. 2).

Jan 1, 1949

By Arthur S. Dwight

From the latest and best literature on lead-smelting, little can be learned concerning the present state of the art of mechanical feeding in the United States. H. O. Hofman, in his Metallurgy of Lead (5th ed., 1899), briefly describes the main features of the system in use at Pueblo, Colo., and later (p. 235) says " the only successful mechanical feeding, as far as the writer is aware, is that found at the works of the Pueblo Smelting and Refining Co." H. F. Collins, in his Metallurgy of Lead and Silver (London, 1899), covers American practice pretty thoroughly; but as to mechanical charging, he says: "The German plan of taking off the gases by means of a small iron pipe suspended in the center, and the plan of charging by means of cup and cone, as in iron blast-furnaces, have both been tried, but have not found favor, chiefly on account of the difficulty of obtaining free access to the furnace-shaft for barring, etc., with such devices."' . H. W. Hixon, in his Notes on Lead and Copper Smelting (3d ed., New York, 1900), gives a description and drawing of the Hixon feeding device, as originally installed at East Helena. Evidence that this system of feeding has passed its experimental stage, and deserves more serious consideration than it has heretofore received, is furnished by two large plants—the Pueblo and the East Helena—of the American Smelting and Refining Co., where mechanical feeding has been in continuous and successful operation for a considerable period; one new plant now erecting at Salt Lake City, Utah, and one old one belonging to the same company, the El Paso works, now being rebuilt after a disastrous fire, in both of which mechanical feeding is to be a prominent feature ; one new plant of an independent concern at Torreon, Mexico, which will adopt mechanical feeding; and a number of other smaller plants, among

Jan 1, 1902

By Henry Schaefer

Solution by electric analogy of performance problems of reservoirs containing oil and gas has heretofore depended upon a process of successive approximations based on material-balance calculations, because of variation in fluid compressibility. By the addition or subtraction of electric condenser capacity, the analogy network can be adjusted automatically for changing compressibility due to evolution of gas in the reservoir. The addition of a condenser is accomplished by an electronic circuit, which is described; subtracting a condenser is done by merely opening the electrical circuit by means of a relay. Introduction V. Paschkis and H. D. Baker1 first developed in this country a method of applying the analogy of flow of electric current in noninductive circuits to solution of heat-flow problems and suggested its application for certain other problems, such as flow of fluids or mass transfer and chemical diffusion. Necessary details for applying the analogy to flow of fluids in porous media were developed by IV. A. Bruce;= he classified3 the types of analysis and predictions that can be made by the analogy in class I, when the reservoir contains oil but no gas for the period under consideration; in Class 2, when both oil and gas exist in the free state in the reservoir sometime during the period under consideration. Duplication of bottom-hole pressure history and predictions for class I reservoirs can be obtained directly by electric analogy. Until now, the solution of problems pertaining to reservoirs in class 2 was obtained by successive approximations along with material-balance calculations. The object of this paper is to present a method for simplifying the application of electric analogy to class 2 reservoirs, resulting in a solution of these problems as direct as is possible for class I reservoirs. This is accomplished by an electronic control circuit, which adjusts the analogy network for changing compressibilities of fluids contained in the reservoirs. Analogy Network In electrical phenomena the analogy to two-dimensional fluid flow in a porous media is that of current flow through an ideal conducting sheet. This sheet, perfectly insulated on both sides, has resistance and capacitance uniformly distributed throughout its area but is of negligible inductance. The need for having the surface boundaries perfectly insulated is that good correspondence may be had with a permeable fluid-conducting stratum bounded above and below by impermeable media. 111 actual application the ideal conducting sheet, which has distributed parameters, is replaced by a network having lumped values of resistance and capacitance—the resistances are series elements and the capacitances are shunt elements. The larger the number of lumped

Jan 1, 1947

By E. Northcott, F. N. Oberg

By electrostatic separation, course Florida pebble phosphate, too lou-grade to find a ready market, can be upgraded to a satisfactory saleable product. Pebble running from 60 pct bone phosphate of time may be upgraded to 73 to 77 pct BPL depending on the mineralogical. structure of the pebble and the nature of the silica innpurity. High-grade concentrates from Florida pebble phosphate deposits have long been recovered by wet methods. When work was begun in the field, only the coarse pebble (generally +1 mm) was re- covered. In the 1920's a froth flotation process was developed to separate quartz from the finer phosphate fractions, but this method proved unsatisfactory for treating the intermediate fraction (—1 mm +35 mesh). Consequently various other processes were adapted, including agglomerate tabling and spiral separation of reagentized feed. Today the three processes are used—washing and screening for coarse pebble, tabling or spiraling for intermediate sizes, and flotation for —35 mesh material.

Jan 1, 1959

By E. G. Spilsbury

AS a fresh illustration of the advances made in the past few years in the overhead-cable systems of hoisting and conveying, as applied to open-cut deep mining and quarrying, I would call attention to a further development of this system of transportation which has lately been put in operation i-n this State. A few miles above Williamsport, on the Susquehanna river, the Glen Union Lumber Company, of Pottsville, Pa., owned a large tract of valuable timber-

Jan 1, 1892

By Lance R. Barron

The U.S. Bureau of Mines (USBM) conducted ground pressure analysis of a wide abutment-type chain pillar in a two-entry gate road of a Western U.S. coal mine with an extremely weak immediate roof. About 15 m of fragile, low-strength mudstone lies between the seam and the lowest competent roof member. Three-and two-entry gate road designs with several pillar sizes and various secondary support systems have been employed to improve tailgate-entry stability, with varying results. This report discusses gate road layout and performance and secondary support effectiveness. The results of the pillar pressure study are compared to pillar loading predicted by a widely used pillar design method and to similar studies in other mines. A stability evaluation of the most recent longwall headgate, using the USBM Analysis of Longwall Pillar Stability (ALPS) method, indicates marginal stability in first-panel mining and instability in second-panel mining. The ALPS method and the USBM Coal Mine Roof Rating system are used to evaluate tailgate-mining stability of the previous gate roads and to determine pillar and entry width and top coal thickness criteria for tailgate stability in future panels.

Jan 1, 2010

By R. Owen, T. Canty, C. Marks

The industrial vision system provides on-line 2D particle size analysis for aggregate slurries in both the overflow and underflow of hydrocyclones. This paper covers required vision system features allowing CCD cameras to function in the harsh environment of a mine milling area. The study conducted demonstrates the system’s capacity to obtain particle size distributions for controlling hydrocyclonic separators. The particle size distribution is obtained within seconds and immediately updated to allow for process adjustments. Results are then provided as a graphical computer generated display or output as a 4-20mA current loop for process control. The primary use of the vision system is in classifying particles in cyclone overflows which are often a few microns in size. Typical size information for actual mine slurry samples are presented and possible control schemes discussed.

Jan 1, 2002

Narrow vein mining, with enough challenge and also where the cutting edge technology can be applied, is still a very important and exciting portion of the mining industry. Based on the deposit characteristics, the most flexible mining method, cut and fill, has been being tested mining this high grade Northern Nevada property, Hollister, since the year of 2008. In the last three years, 254,000 tons of ore were hauled out of the portal and 23,000 feet of development were excavated underground with the winning of several safety and environmental awards. Together with mine geology, the essential segments include mining cycle, ground control, ventilation, grade control and backfill method in cut and fill stopes were covered in this paper.

Jan 1, 2012

By Joseph E. Pogue

In 1920, 531 million barrels of crude petroleum were coi~sumed in the United States. As imposing as this figure is, the fact that the domestic consumption of crude petroleum has increased at an average rate of 10 per cent. a year for the past decade is more striking. Will this rate of increase in demand continue? If so, the year 1930 will call for 1260 million barrels of petroleum—a staggering volume. On the other hand, may we expect the demand for petroleum to grow as rapidly as it did when the automotive industry was having its most phenomenal expansion? If not, to what extent will the growth of oil requirements decrease? When and to what degree will the petroleum industry become affected by the economic law of diminishing returns? Obviously, this matter requires careful analysis, especially as both national and industrial planning must be predicated upon present estimates of the requirements of the future. The purpose of this paper, accordingly, is to project, as closely as present limitations of knowledge permit, the course of the demand for petroleum in the United States over the next ten years. At first, the problem of estimating the future of a demand as complex as that for petroleum might appear insoluble. Fortunately, hon~ever, therc are several scientific methods of approaching the problem, centering around a study of rates of industrial growth, which lend considerable hope that the requirements of the immediate future in this field may be approximated with sufficient closeness to have practical value as a basis of action. Growth oF Petroleum Demand The demand for crude petroleum is the resultant of the demands for the products made jointly from this substance—gasoline, kerosene, gas and fuel oil, and lubricating oils. The demands for these have grown at

Jan 1, 1923

By K. Wongaew, R. F. Cook, J. E. Carlson, T. Cleys, C. R. Smith

Steel fiber reinforced concrete segmental rings are the final tunnel lining for approximately 85% of the alignment for a 6.706-meter (22-foot) internal diameter tunnel being built as part of the East Side Combined Sewer Overflow Tunnel Project. This paper describes the approach adopted for the design of the steel fiber reinforced concrete segments, the development of the performance criteria for the segments, and the testing program used to confirm the performance of the materials and segments in the laboratory and in the field.

Jan 1, 2007

By A. Deepatana

Bioleaching of nickel laterite ores is based on the use of heterotrophic fungi organisms and their metabolites (organic acids) to dissolve nickel and cobalt from oxide minerals to form metal-organic complexes. Metal recovery from this process using an aminophosphonic acid based chelating resin (Purolite S950) was investigated as a function of metal concentrations, complexing agent including citric, dL-malic and lactic acids. Batch adsorptions were conducted using synthetic leachate solutions of nickel and cobalt with concentrations from 15 to 2000 mg/L prepared in 0.01 and 0.1 M organic acids. Adsorption equilibrium data were interpreted using the Langmuir, Freundlich and Dubinin-Kagner-Radushkevich (DKR) models. The results showed that equilibrium adsorption data for nickel-organic complexes followed the Freundlich model and those for cobalt agreed with the Langmuir model. It was observed that the maximum adsorption capacities of nickel and cobalt were 3.26 and 10.48 mg/g resins respectively. These were achieved in metal complexes prepared from 0.01 M lactic acid. Metal elution was conducted using 2 M nitric acid. High metal recoveries were achieved from low metal concentrations but were found to decrease with increasing metal concentration. The results suggest that effective recovery of nickel and cobalt from low concentration of metals, such as those generated from bioleaching operations, can be achieved suitably using chelating resins.

Jan 1, 2006

By Low J. R., Gensamer M., W. T. Lankford

The problem of sheet metal formability is one which has received a vast amount of attention during recent years. In spite of the great amount of study and experimental work which has been devoted to this problem, many of its fundamental aspects are still not well understood. No generally satisfactory test has been developed which is capable of providing a reasonably adequate evaluation of sheet metal formability, particularly in borderline cases. Anomalies persistently arise in which a lot of supposedly satisfactory material exhibits excessive breakage when formed. This lack of suitable technological tests greatly hinders the design of new parts and the substitution of new materials in parts of existing design, frequently necessitating considerable costly trial and error experimentation on an actual production basis. When, at the beginning of World War 11, it became apparent that mass production methods of forming would bc required in the aircraft industry if the large numbers of military aircraft needed were to be supplied, renewed attention was focussed on the problem of sheet metal formability. It was widely recognized that the formability requirements placed on sheet metals had been steadily increasing in severity through the years, especially as greater and greater emphasis was placed on streamlined designs with the resultant freer application of doubly curved surfaces. The recent advent of several new high strength aluminum alloys of more limited formability than some of the older alloys also served to emphasize the need for new approaches to the problem. It seemed evident that progress in the technology of sheet metal forming would depend to a great extent on the development of more reliable criteria for the evaluation of formability. Although the problem is admittedly very complex, the most logical approach appeared to be through studies of the fundamental material properties of sheet metals, especially under complex stress conditions simulating those prevailing in actual forming operations. Most previous investigations have failed to make full use of existing knowledge of fundamental material properties, and in many instances have attempted correlations with properties which are now recognized as being ambiguous in nature. This investigation was undertaken, therefore, with the aim of developing methods for the study of the flow and fracture of sheet meta1s under combined stresses, and of making use of such methods as might be developed in

Jan 1, 1947

By R. F. Krueger

Results are presented from tests of dynamic fluid-loss rates to cores from clay-gel water-base drilling fluids containing different commercial fluid-loss control agents (CMC, polyacrylate or smt,ch), organic viscosity reducers (quebracho and complex metal lignosulfonate) and oil at several different levels of concentration. In the dynamic system the most effective individual additives to the clay-gel drilling fluid, based on cost-equalized concentrutiom, were found to be starch and the viscosity reducers. These results do not conform with the rankings determined by API fluid-loss rests, which indicate CMC, polyacrylate and starch to be the most effective and comparable. Generally, minimum dynamic fluid-losr rates were attained at cost-equalized concentrations of additive (including thinner) of about $1.00/ bbl, or less. For chernically treated clay-gel drilling fluids, both the standard and the high-pressure API filter-loss tests were found to he inaccurate indicators of trends in dynamic fluid-loss rates under the test conditions used, particulurly for drilling muds containing viscosity reducers. From a practical field viewpoint, restrictions on the applicability of the API fluid-loss test are such that it is open to question whether or not results of this test can be used routinely with confidence as an indicator of control of down-hole fluid loss under field treating conditions. INTRODUCTION The petroleum industry spends large sums of money during drilling operations to control the fluid-loss properties of drilling fluids based on the standard API filter-loss test,' which is a static filtration system. Laboratory studies' ' of dynamic filtration have shown that in a given time period filtrate loss from a circulating mud stream is greater than from a static system and that it is a function of linear mud velocity, pressure and the properties of the drilling fluid. Ferguson and Klotz' and Horner, et al," observed that (I) the dynamic fluid-loss rates for the drilling fluids used were not related to the extrapolated API filter loss and (2) the drilling fluids with the lowest API filter losses did not have the lowest dynamic fluid-loss rates. However, there has been no published information on the relative effects on dynamic fluid-loss rate as a given drilling fluid is treated with increasing amounts of chemical additive to reduce the API filter loss. Such information is economically important because drilling-fluid costs rise rapidly as chemical requirements increase. This paper presents the results of a study of dynamic filtratioi rates to cores from a clay-gel water-base drilling fluid treated with various commercial viscosity reducers and chemical fluid-loss control agents. The dynamic fluid-. loss rates to cores are compared with the standard API filter-loss values at several different levels of additive concentration. Dynamic filtration rates were obtained in each experiment under two different simulated wellbore conditions: (1) filtration just above the bit through a new mud cake laid down dynamically on a freshly drilled formation and (2) filtration up-hole through a mud cake formed by deposition of a static filter cake on top of the initial dynamically formed cake. The latter case corresponds to the bottom-hole conditions existing above the bit when mud circulation is restarted after a stand of pipe has been added or a round trip has been made to change the bit. Except for the short-duration, high-rate filtration beneath the bit where no mud cake can form, these two conditions probably represent the two extremes of dynamic filtration. Because thickness of a dynamic mud cake formed on freshly exposed formation is limited by the shearing action of the mud stream, the filtration rate for this condition is high. On the other hand, once circulation is stopped and a static mud cake forms on top of the dynamic cake, re-starting circulation has only a small effect on the cake properties and filtration rate is much lower thereafter. A discussion of the mechanics of mud-cake deposition and dynamic filtration is outside the scope of this paper but may be found in more detail in publications by prior investigators. APPARATUS AND EXPERIMENTAL CONDITIONS The test equipment used to simulate the dynamic flow conditions existing during drilling was a modification of that described previously by Krueger and Vogel: A schematic flow diagram is shown in Fig. 1. In general, a power-driven, high-pressure mud pump capable of delivering up to 60 gallmin was used to circulate drilling fluid parallel to the faces of 1-in. diameter sandstone cores mounted in a 2 3/4-in. ID high-pressure test cell. Pump rates were controlled by means of a magnetic clutch to maintain an average axial fluid velocity of 110 ft/min in the annular space between the cell wall and a 1 1/2-in. rod positioned on the center line of the cell. The core specimens were Berea sandstone plugs sealed with plastic inside 1 1/8-in. OD tubes and were fluid-saturated prior to use. Burettes were used to accumulate fluid discharged from the cores. The mud sump shown was used for treatment and storage of the drilling-fluid samples during a particular test. The valve arrangement permitted either (1) circulating drilling fluid through the by-pass line while treating with

In the current climate, there is a real need to bridge the gap between theory and the real world mining considerations, and develop viable, cost-effective, high performance thickeners. With a greater need to extract profits from both difficult-to-process ores and lower grade orebodies, coupled with the necessity to produce 'greener', less water intensive technologies, suppliers need to take current thickener designs to the next level and into the 21st century. The complexity of 'getting it right' within a thickenerÆs feedwell, the 'nerve centre' of the thickener, is no small task. Delivering dilution water and mixing this water with incoming feed slurry, addition of flocculant, maximising flocculant-slurry interaction to build aggregate size, minimising unabsorbed flocculant percentage, volume average of solids volume fraction, momentum dissipation ratio, dilution recycle ratio, volume average shear, maximum shear rate at exit, aggregate size on exit, uniform discharge profile and more ù all of these need to occur in the right order and in the right proportions within the feedwell. This paper discusses the genesis and evolution of a new feedwell design, the first major innovation in the thickening industry in over 15 years.

Jan 1, 2008

By N. Ward

The Gualcamayo Mine is located in the Andes Mountains north of San Juan, Argentina (Fig. 1). A property of Yamana Gold Inc., it declared commercial production in July 2009 and has a total mineral reserve and resource base of approximately 88 t (3.1 million oz) of gold. Crushing operations for the openpit mine are located in a 13,500-m3 (477,000-cu ft) underground cavern with a ceiling height of 22 m (72 ft). More than 3,600 m (11,800 ft) of tunnels are used to access the cavern and convey the ore. The project as described in this paper relates to the design and construction of the main cavern, conveyor system exit tunnel, the mechanical system access tunnels and two 4.2-m- (13.7-ft-) diameter shafts (Ore Pass #1 and Ore Pass #2) (Fig. 2). Preliminary engineering for the project was performed by Hatch Chile. Rizzo Associates Argentina, S.A., a division of Paul C. Rizzo Associates, Inc. (Rizzo), was contracted to provide geomechanical and geotechnical support for the construction of the access tunnel system and geomechanical design and construction supervision for the cavern and shafts.

Jan 1, 2011

By Russell W. Mumford

LITHIA compounds have a place in pharmaceutical and other chemical industries and lithium minerals in glassmaking and ceramics. The metal, although rare, is used to a minor extent in alloys. During the nearly 50 years of production of lithium minerals in the United States, the silicate mineral spodumene has continued as the chief source of raw material for the manufacture of lithium salts. Although twice as much lepidolite, a lithium mica, has been mined, most of it has been used in the making of certain types of glass. Amblygonite has been an additional but minor source of lithium compounds. Triphylite, petalite, and zinnwaldite have also been utilized in the past. All of these commercial lithium minerals contain low percentages of lithium (Table 1). In 1938, a new raw material for manufacture of lithium compounds made its appearance. This product was crude dilithium sodium phosphate (Li2NaPO4), obtained as a by-product of manufacture of potash and soda chemicals from the brine of Searles Lake, California. Searles Lake, which is now dry, lies in the extreme northwest corner of San Bernardino County, California, and consists of a large mass of salts. It was estimated by the United States Geological Survey that the crystal body contained about 25 pct voids, which are filled with a saturated brine. The brine consists mainly of the sulphates, chlorides, carbonates, and borates of sodium and potassium. Several other acid radicals, including phosphates, are present. Lithium is present in the brine in an amount corresponding to 0.01 15 pct Li2O. In the course of evaporation of water from the brine, during the process of manufacture of sodium and potassium chemicals, dilithium sodium phosphate crystallizes out and is recovered by a flotation operation. The lithium concentrate is filtered and dried and is then ready for shipment. It analyzes from 19 to 21 pct Li2O and now constitutes the highest known grade of crude lithium material. It is and will continue to be a major source of lithium for manufacture of lithium products. The variation in lithia content of the commercial minerals as mined is due to replacement of the lithia by soda and potash, to partial alter-

Jan 1, 1949

By G. W. Elger

The Bureau of Mines investigated the conversion, at both laboratory and pilot plant scale, of a low-grade ilmenite to chlorination-grade feedstock that could substitute for imported rutile used to produce titanium tetrachloride. The concentrate was derived from the Tahawus, NY, lode deposit of ilmenite-magnetite in rock that contains anorthosite and gabbro. Charges of the ilmenite concentrate, containing 46.6 wt pct Ti02 blended with soda ash, were carbothermically reduced in an electric arc furnace, which separated most of the iron and left a high-titanium slag. However, the slag contained Ca, Mg, and Mn constituents that rendered the material unsuitable for continuous chlorination by causing plugging problems. After being ground and pelletized, the slag was reacted with S02 and air at 7000 to 9000 C, which selectively converted the harmful impurities to soluble compounds that were removed in a subsequent water or dilute HCI leach. In laboratory tests, the combined levels of harmful impurities were decreased from 5 to as low as 0.5 wt pct in leached slags. In pilot plant tests, leached slags sulfated at a rate of 10 lb/h averaged 85.5 wt pct Ti02 with pertinent impurity levels averaging 1.86 wt pct. The leached slag was successfully chlorinated in a laboratory fluidized-bed reactor at 9500 C to extract titanium as TiCI4.

Jan 1, 1986

By John Wellington Finch

In August, 1927, the writer examined certain copper deposits in New Mexico1 which occur in beds of sandstones and shale, and in connection therewith reviewed the literature upon deposits of this type. Such deposits are known and have been reported upon at various points in Texas, Oklahoma, Arizona, Colorado, Wyoming and Utah, but in New Mexico they have been given more development than elsewhere and apparently occur there more conspicuously than in the other states. Some 25 years ago the writer examined deposits of similar origin in northern Arizona and more recently other deposits in western and southwestern Colorado, and these examinations have led him to realize how widely scattered are the deposits and how generally noncommercial they are. On superficial development, to one without a comprehension of their geologic nature, they are alluring on account of occasional small amounts of high-grade ore and much misplaced capital has been expended upon them. This paper, therefore, aims to present briefly certain theories of genesis, some details of which may possibly be new, and to lead up to practical conclusions which may be useful to other geologists and engineers. A bibliography of the more important literature upon such deposits is given below.2 Coffin's Bulletin upon the Radium, Uranium and Vanadium Deposits of Colorado, published in 1921, is a particularly clear discussion. The most comprehensive recent statement is Butler's.

Jan 1, 1928

By William F. Riggs

Inspiration Consolidated Copper Company, located in a semi-arid climate in Arizona, continually struggles with a water problem. This applies to quality as well as quantity. When the EPA considered installing a new centralized sewage plant to handle the combined waste from the municipalities of Globe and Miami, Arizona, they automatically assumed that He could use the sewage effluent for process water in flotation. The treatment plant was to be a tertiary system producing 1600 gpm of sewage effluent. Inspiration decided that this could possibly be a source of additional process water. It was decided to test sewage effluent from Miami Treatment Plant at the rate of 400 gpm since it was only a primary treatment plant. The 400 gpm was combined with the 5000 gpm of process water going to the Concentrator. After one week the results were disastrous. The recovery and final grade had each dropped approximately 5%. With the results from this brief run, it was concluded that sewage effluent from a primary treatment plant could not be used. Research was then brought into the problem to begin an evaluation of sewage effluent in flotation.

Jan 1, 1977

By M. Amick, G. Swan, R. Hill, C. Pritchard

Falconbridge is a major basemetal producer in the Sudbury Basin of Ontario, Canada. The company identified a need to find a safe and cost-effective replacement for the welded wire mesh used to support loose ground during underground nickel mining. Falconbridge took a methodical approach to the concept of a spray-on liner as a screen replacement, proving the strength characteristics of the liner as a safe, cost effective and suitable method of supporting ground Compact, hydraulic mixing and spraying equipment were developed and are now in use at the Fraser Mine. Tekflex has been approved as a wire mesh replacement and has been in use since November 1998.

Jan 1, 2002