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By Don Deardorff, Ke Yang, Yingcai Han, Ken Sorensen, Robert Kruger, Mark Petersen, Diane Fiorelli, Larry Goldfarb, Kathryn Petek, Kwabena Ofori-Awuah

Design of deep foundations for lateral loads requires an understanding of soil-foundation-structure response during loading. Lateral loads on a deep foundation (piles) could be due to earthquakes, winds, waves, and/or machine vibrations. Over the years, analysis of response of piles due to lateral loads evolved from closed-form solutions to p-y methods to strain wedge to finite element/finite difference modeling. Although analysis of lateral response of piles and shafts is routinely performed, there is no single guidance document and/or standard for design and testing. Several different analytical methods are available for the analysis, and the resulting design can result in significantly different responses which can create confusion. This is especially true for analyzing and designing piles in potentially liquefiable soils with lateral spread issues under seismic conditions.This guidance document is intended to assist geotechnical engineers, pile designers, and contractors in analysis, design, and testing of piles and drilled shafts for lateral loads. This document discusses the background of different analytical and testing procedures and presents the recommended methods for analysis, design and testing of piles for lateral loads.Chapter 1 defines the different kinds of lateral loads to which a single pile or pile group may be subjected. This first chapter also presents different types of piles used to resist lateral loads.Chapter 2 discusses geotechnical issues related to lateral pile design such as liquefaction and lateral spreading and other non-seismic issues. Also addressed in Chapter 2 is geotechnical site characterization (as related to lateral loads) in terms of site investigation, in-situ testing, geophysical testing, laboratory testing, and estimation of soil/rock properties.Chapter 3 discusses the background and available analytical methods and tools for the analysis and design of single piles and drilled shafts. Several methods of analyses from closed-form elastic solutions to the finite element/finite difference solutions and their applicability are discussed. Available commercial computer software packages for analyzing single piles and drilled shafts are also presented.Chapter 4 expands the discussion of single piles and drilled shafts into the analysis and design of pile groups. In addition, group effects, resistance of pile caps, results of previous experimental and analytical studies, and available analysis tools and software for pile groups are discussed.Chapter 5 presents the issue of lateral resistance of piles and drilled shafts as discussed in different national and international building and non-building codes. A summary of extensive research on several codes are presented to facilitate the compliance with different codes.Chapter 6 discusses structural design issues of individual piles and drilled shafts such as depth of fixity.Chapter 7 discusses soil structure interaction issues related to kinematic and inertial effects due to seismic loading and available methods of analyses.Chapter 8 discusses and presents the typical procedures for the lateral load testing of piles. This guideline was developed as an aid to the practicing engineer in providing information, direction and commentary on the lateral design of deep foundations. Although all reasonable effort has been made to accurately compile the material and information contained herein, no warranty is made with regard to any such material or information and the Deep Foundation Institute assumes no responsibility for any possible errors or any direct or indirect result of the use of any such material or information. It is not intended that this document address every factor affecting lateral design for every situation. Therefore it is the responsibility of the person utilizing information from this document to confirm that it is appropriate and correct for their situation as well as to understand and properly apply

Jan 1, 2012

By S. B. Christy

This report on the electrodeposition of gold and silver from cyanide solutions represents work that has occupied my time at intervals during the past 20 years. The investigation has been carried on simultaneously with my duties as professor of mining and metallurgy of the University of California. During shis long investigation I have been assisted in the details of the work by, a number of my former students, acting in turn as assistants. Particular mention in this connection is due W. H. Hilton, who graduated in 1900; C. T. Dozier, 1902; N. C. Stines, 1905; H. N. Herrick, 1907, and L. C. Uren, 1911. It is impossible to publish full details of the many thousands of experiments performed. Effort has been made to present only the essential data. Wherever possible, the results of the experiments have been expressed in diagrammatic form by curves showing the relation between the simultaneous variables of the experiments. It is necessary to show, as nearly as may be, the state of the art. This is difficult because of the meager literature on electrodeposition in the cyanide process; hence resort must be had to the specifications and claims of patents, most of which seem never to have been applied on a working scale. Such information consequently can not be taken at its face value. Expressing the essential ideas evolved in such specifications is no easy task. Clearly, in quoting from patent records it is not ·feasible to enumerate all of the specifications or the claims allowed the inventors. A statement of the chief contributions to the art in the patent cited must suffice. Legal details, of course, must be obtained from the original patent. In the study of patent literature, when one compares the ardent hopes of the inventors with the results realized from their efforts, it becomes clear that in the development of an art no one man contributes everything. Each subsequent inventor stands on the shoulders of the one who has gone before. It is only through the summation of the contributions of many inventors that the art as a whole prospers. On October 19, 1887, a British patent was granted to McArthur and Forrest for the use of dilute cyanide solutions for treating gold and silver ores. The rapid extension of this process, in various forms, all over the world, has almost revolutionized the treatment of ores containing precious metals. It is a remarkable fact, however, that long before this patent was granted there was issued, on February 5, 1867, to J. H. Rae, U. S. patent 61866, for an electrocyanide process. Thus a method of electrodeposition from cyanide solutions used for treating ores was invented 20 years before the McArthur and Forrest patent .was granted, although the process did not come into general use. On May 24, 1889, U. S. patent 403202 was granted to McArthur and Forrest for the use of zinc shavings for removing gold and silver from cyanide solutions. The use of finely divided zinc is still the standard method for recovering 'gold and silver from cyanide solutions. Since this patent was granted, many attempts have been made to replace the precipitation upon the zinc by methods of electrodeposition. It is the purpose of this report to give an outline of some of these methods, as well as to show the relative advantages and disadvantages of the zinc and the electrical methods of recovering gold and silver from cyanide solutions.

Jan 1, 1919

By GEORGE S. POPE

The Government of the United States annually expends approximately $8,000,000 for coal. Prior to 1906, this coal was purchased mainly on its reputation, or trade name, rather than under contracts specifying the heating value of the coal, its contents of ash and moisture, and other characteristics. In recent years the Government and other large consumers have appreciated more and more the desirability of definitely determining by chemical analyses and tests the character and quality of coal deliveries. Studies of engineroom and boiler-room efficiencies and economies point forcibly to the necessity of devoting more thought to the improvement of the boiler-room end. This calls for an intimate knowledge of the character and quality of the fuel used. The analyses and tests of delivered coal furnish such data, whereby the power-plant results can be comprehensively studied and a continuous check maintained on the coal and on the conditions of plant operation. Under authority of acts of Congress making appropriations for analyzing and testing fuels belonging to or for the use of the United States Government, a laboratory is maintained at the headquarters of the Bureau of Mines, 'Washington, D. C., where samples representing deliveries of coal purchased for Government use are analyzed and tested. The Bureau of Mines has been active in promoting the purchase of coal by the Government under specifications,a that is, by contracts that make definite requirements regarding the heating value of the coal expressed in British thermal units, and the composition as shown by proximate analysis. Under many of these specification contracts the bidders guarantee the quality of the coal offered, and that guaranteed by the successful bidder becomes the standard of his contract. The deliveries are sampled and analyzed to determine whether the coal is of the quality guaranteed by the contractor, and if it is not, the price to be paid is decreased in proportion; but if the coal is of higher quality, the price is proportionately increased. The analyses of coals or the guaranties offered by the bidders may in some cases be used for determining the award of a contract, but if the coals offered are of widely different characteristics, it may be difficult to determine which would prove the cheapest fuel, without having their relative evaporative efficiencies. Hence, it may be necessary to conduct evaporative tests under service conditions in order to determine which coal is particularly adapted for successful and economical use in the plant. But once a particular coal is selected, regardless of the procedure of determining the award of a contract, then the greatest advantage of the specification method is realized, in that it guarantees to the purchaser coal of uniform character and quality, thereby insuring the best results in the plant. The cost of purchases, under such specifications, of fueL for the use of the Government now aggregates approximately $4,100,000 per annum, and the cost of additional fuel for which samples are taken and submitted to the Bureau of Mines for analysis in order to determine the character and quality of the coal furnished aggregates some $3,000,000 per annum more. In fact, information is now obtained regarding the quality of fuel purchased on almost all contracts large enough to warrant sampling and analysis and heatingvalue tests. It may be said that the purchase of coal under specification is still in the stage of evolution and development, and that experience and time will be required to develop fully standard specifications and methods of sampling and analysis that may be used universally. The success of the specification method for the purchase of coal and the reliability of analysis now rests almost entirely on sampling.a Improper sampling leads to controversies, with resulting condemnation of the specification method in general and the value of laboratory analyses and tests in particular. A number of bulletins b have been published showing the results of the purchase of coal by the Government under specifications. This bulletin is a compilation of the results of coal analyses by the Government, including those made in the fiscal years 1908-1910, which have been previously published, and later analyses representing coals analyzed during the fiscal years 1911-1915. The preceding bulletins gave individual analyses or average monthly analyses, whereas this bulletin gives the average analyses only for the entire contract. It is hoped that this compilation of a series of comparable analyses of the coals purchased by the Government will be of value alike to coal dealers, to Government engineers, to purchasing agents, and to all users of coal.

Jan 1, 1916

By Amr Sallam, Ahmad Mohamed, Mohamed Alrowaimi

Renewable energy, in the form of wind and solar, has emerged as main source of energy in the modern society. The wind industry has substantially grown over the last two decades to become a key player in providing energy to public. Wind turbines are getting larger, taller, and more efficient every year. The foundation is a major component of the wind turbine system. The wind turbine foundation must provide short and long-term stability for the overall turbine to allow continuous and safe turbine operation for energy production. The turbine serviceability and stability requirements must be geotechnically and structurally satisfied. In North America, major foundation types currently utilized in the wind industry include gravity spread foundation, mono pier foundation, and pile foundation. In this case study, a Post Tensioned Pile Cap (PTPC) foundation was used to support a 3.15-3.4 Megawatt turbine with 125M Rotor supported on 87.5M-hub-height tower. Soil anchors in the form of Auger-Pressure-Grouted-Displacement (APGD) piles and Continuous Flight Auger (CFA) piles were utilized. Four distinct subsoil conditions were identified, and for which four pile designs were adapted. Due to the occasional encounter of stronger soils at 50 to 55 feet (15.2 to 16.7 m), shorter pile design was preferred. To satisfy the design uplift load, pile post grouting were utilized to increase the shaft capacity of the piles. In this paper, the pre-production pile load test program will be described. The pile load test procedure, analysis, and results will be presented. A discussion will be provided, which led to the selection of the optimum pile design to support the high tension loads taking into consideration pile length limitations.

By James M. Barker

Industrial minerals are critical to most aspects of modern society. They are pervasive in both industry and in everyone's lives (McVey, 1989; Barsotti, 1993). They are also the dominant class of minerals produced in the United States but this fact is little known outside the industry. For example, in 1993 (U.S. Bureau of Mines, 1995, table 1) industrial mineral dollar value was double that of metals ($20.86 billion vs. $10.88 billion) and employment levels were nearly so (74,000 vs. 40,000). A further difference is that transportation tends to dominate production costs (FOB end user) whereas they are much less significant in other mining ventures or other industries. Finally, metal mines are more concentrated west of the Mississippi; industrial mineral operations are more prevalent to the east (U.S. Bureau of Mines, 1995, p. 16-17). The significance of transport cost is discussed in Part 2, which is essentially Barker and Austin, 1995. Part 1 will update and expand portions of Barker and Austin (1995) and provide a more detailed discussion of import/export relationships using a China/United States reference point because of China's dramatic influence on some industrial mineral markets since the mid-1980s (barite, etc.).

Jan 1, 1996

By Wiliam L. Crentz

The importance of Somerset County, Pa., as a coal producer is due in large measure to the presence reserves of low-volatile bituminous coals. Although many coal beds of minable thickness are present, the important reserves are to be found in those beds underlying the Pittsburgh bed. The Kittenning beds and Freeport beds, which are responsible for the bulk of the present coal production in Somerset County and contain the largest reserves to meet future coal requirements, are usually thin and entirely free from impurities. The Pittsburgh bed, which has been such an important coal deposit in the coal areas immediately west and south of Somerset County, is of secondary importance in this county. Although generally rather friable, Somerset County coals have enjoyed wide receptability as excellent coals and to some extent have been utilized in the metallurgical market.

Jan 1, 1951

By Elmer W. Pehrson

Minerals have played a prominent role in the affairs of man and nations since time immemorial but with the advent of the industrial revolution, expanding use of the products of the mineral kingdom became synonymous with the material progress of mankind. Individuals and business groups have recognized this fact so have been aggressive in searching for and utilizing mineral resources, with notable success. Indeed, their achievements are primarily responsible for the present Machine Age. On the other hand, until recently the body politic has failed to grasp fully the essentiality of minerals although, at times, access to mineral supplies has been an important factor in the political maneuvers of nations. This chapter is concerned primarily with the broader political and economic relationships of mineral resources to the world economy, and with the internal and external actions of nations in the field of minerals. Many factors that condition the mineral economy of regions and the world as a whole, influence the internal and external affairs of individual nations. The more important of these are: 1. The nature of man's dependence on minerals. 2. The problems resulting from the unique characteristics of mineral occurrence. 3. Geopolitical concepts. 4. Minerals and world power. Actions of individual nations affecting their mineral economy seek two basic objectives : 1. Attainment and maintenance of prosperity. 2. Military security. Other objectives may be cited but on careful analysis they become integral parts or extreme phases of the two points noted above. For example, the twentieth century aggressions of the USSR, Germany, Italy, and Japan might be considered as direct bids for world power but they also can be interpreted as exaggerated or mistaken efforts toward military security and peacetime prosperity. Similarly, trade barriers, nationalization of industries, foreign exchange manipulations, taxation, monopolistic prac-

Jan 1, 1959

By João Luiz do Vale

In standard wear tests, such as pin on disk (ASTM-G99) or block on ring (ASTM-G77), the apparatus simulates conditions that are often different from a machine element real application. Therefore, for an accurate investigation of a tribological application, it is essential to test the real condition in which there are similarities as: geometry, contact details, force application mode, materials, among others. It emphasizes that for studies involving polymeric materials it becomes extremely relevant. Thus, the Laboratory of Surfaces and Contact (LASC) at UTFPR developed an apparatus for sliding bearing on shaft test. In that equipment, loads are applied by a dead-weight system and the frictional force is measured on a load cell. The apparatus operating ranges for load added to the dead weight system and rotation shaft are from 0.2 to 5.0 kgf and from 260 to 3500 rpm, respectively. This paper presents a detailed evaluation of such apparatus, which includes free-body diagrams analysis and a deduction to obtain an equation for the kinetic friction coefficient. Also, the standard measurement uncertainties of a caliper, an electronic scale, and a cell load were determined. It was verified that the kinetic friction coefficient equation is dependent on the apparatus geometry, the applied load, and the frictional force value. Additionally, through the statistical significance analysis it was concluded that some terms in the equation were not significant. Finally, through the application of the error propagation theory in the kinetic friction coefficient equation, the standard measurement uncertainty of the apparatus which showed a value nearby 0.002 along the operating range of the apparatus was obtained.

Jul 31, 2018

By H. J. Roorda

With an increasing need to obtain metals by processing complex fine intergrown ores, the use of electron-optical techniques will become more important as a tool for mineralogical studies. Electron images enable a higher spacial resolution than can be obtained by optical microscopy and thus provide a powerful and necessary aid for the examination of small grains and finely locked particles. In this paper the mineralogy of Meggen ore was investigated. Both light-optical and electron-optical techniques were used to evaluate the mill feed and products of the concentrator. Detailed examination by reflected-light microscopy to assess the comportment of galena in the complex pyritic ore was inconclusive in establishing the cause for low lead recovery of only forty percent of the ore's lead content. Electron microprobe analyses indicated that the majority of the lead lost to the tailings was accounted for by extreme fine (often smaller than one micron) and complex intergrowths of galena in pyrite. The remainder was lost as fine free galena grains.

Jan 1, 1987

The properties of interfacial water at hydrophilic surfaces are of great importance in many technological areas including flotation, solid-liquid separation, dispersion and emulsions, flocculation, adsorption, corrosion, and soil contamination. This paper examines the use of FTIR/internal reflection spectroscopy (FTIR/IRS) to study the spectral characteristics of interfacial water at silica surfaces. FTIR spectra were characterized by consideration of the OH stretching region (3000-3800 cm-1) associated with the vibrational spectra of interfacial water. The broad peak in this region was deconvoluted in order to isolate overlapping spectral features that describe the nature of hydrogen bonding in interfacial water. Three distinct bands were found; -3600 cm-1 (free OH), -3400 cm-1 (incomplete tetrahedral coordination), and -3240 cm-1 (complete tetrahedral coordination) and the variation of their intensities with pH was found to be significant. This spectral information helps to explain orientation and bond ordering of interfacial water molecules at hydrophilic surfaces.

Jan 1, 1998

By G. A. Brooks

Reactive ball milling has been proposed as a new route for producing carbides from oxides through carbothcrmic reduction. It is claimed that through milling oxide and graphite powders to the nanoscale, amorphous materials with very high reactivity are formed, that allows for easy transformation of the starting material to another in a subsequent thermal process. Thermodynamic analysis of this proposed process suggests that unless particle sizes are reduced to below 10nm, then reduction in size alone cannot explain a change in the stability of oxides. Even with nanometer scale powders, the products formed need to have a lower total surface energy than the reactants before a chemical change will occur. A model developed by Bhattacharya and Arzt for predicting localized temperature changes based on milling conditions suggest that temperarure rises less than 400 K will be achieved in laboratory conditions. The present calculations suggest that nanometer scale powders formed through high speed ball milling (>10 mls) may have undergone a process analogous to melting and quenching. Further work is required to fully distinguish these features.

Jan 1, 2003

By B. Abedian, L. M. Racz, S. R. Berry, R. W. Hyers

"The presented work represents an effort to improve understanding and prediction of turbulent flow inside electromagnetically-levitated droplets. We show that the flow field in a test case, a nickel droplet levitated under microgravity conditions, is a low Reynolds number turbulent flow, i.e. in the transitional regime between laminar and turbulent. Past research efforts have used laminar, enhanced viscosity, and k - E turbulence models to describe these flows. In our study, we compare the RNG algorithm to laminar and k - E turbulence model results. We show that accurate description of the turbulent eddy viscosity µr is critical in order to obtain realistic velocity fields, and that µr cannot be uniform in levitated droplets. In the RNG method there are no characteristic length or time scales associated with the flow, thus allowing such anisotropic features to be captured. We perform calculations and analyses for two cases (1) a small, non-deforming, spherical nickel droplet and (2) a deforming, oscillating droplet. In addition to flow field calculations, we compare numerically-obtained surface tension and viscosity values to those obtained experimentally by the oscillating drop technique.IntroductionElectromagnetic levitation (EML) is a containerless processing technique for conductive materials. Its advantages are the avoidance of contamination or chemical reaction at container walls and the ability to perform long-term experiments in a metastable state. Because of its current limitation to small sample sizes, its primary use is in the laboratory. One application of interest is the measurement of thermophysical properties of undercooled liquid metals [1, 2, 3, 4]. In EML, a sample weighing approximately 1 gram is positioned inside an electromagnetic field generated by alternating currents flowing through an axisymmetric water-cooled copper coil. The coil must be designed appropriately so that thesample levitates in a stable manner.Traditionally, mathematical modeling has been performed in tandem with both earth-and spacebound electromagnetic levitation experiments, in order to determine the effect of the magnetic field on material and flow characteristics [5, 6, 7, 8]. These calculations are important because they allow design, planning, and correct interpretation of experiments. In addition, the calculations are of fundamental scientific interest, as they can be applied to other electromagnetic materials processing applications [9]."

Jan 1, 1999

By G. A. Brooks

Reactive ball milling has been proposed as a new route for producing carbides from oxides through carbothermic reduction. It is claimed that through milling oxide and graphite powders to the nanoscale, amorphous materials with very high reactivity are formed, that allows for easy transformation of the starting material to another in a subsequent thermal process. Thermodynamic analysis of this proposed process suggests that unless particle sizes are reduced to below 10nm, then reduction in size alone cannot explain a change in the stability of oxides. Even with nanometer scale powders, the products formed need to have a lower total surface energy than the reactants before a chemical change will occur. A model developed by Bhattacharya and Arzt for predicting localized temperature changes based on milling conditions suggest that temperature rises less than 400 K will be achieved in laboratory conditions. The present calculations suggest that nanometer scale powders formed through high speed ball milling (> I 0 mls) may have undergone a process analogous to melting and quenching. Further work is required to fully distinguish these features.

Jan 1, 2003

By Thomas Fraser

WHEN the Bureau of Mines initiated the program of large-scale research and development in the field of synthetic liquid fuels authorized in the Synthetic Liquid Fuels Act of April 5, 1044, the Coal Preparation Section was assigned the task of obtaining data on the preparation characteristics of the coal in large reserves that might be adaptable to use in this new industry. It is natural that, as the rapidly developing general research program brought about new concepts of raw-material quality, preferred geographical location, and the like, the orientation of coal-preparation investigations should have undergone some change. The first major assignment was the sampling and testing of a series of typical American coals deemed to he suitable for hydrogenation based on early research work conducted by the Bureau of Mines. This first series of tests has been completed and is reported in this paper.

Jan 1, 1950

By B. W. Gandrud

This report, consisting mostly of float-and-sink data and washability curves, has been prepared in connection with an exhaustive study of coal preparation in Alabama conducted, by the U, S. Bureau of Mines and the University of Alabama with the cooperation of the different coal operators On the basis of the float-and-sink data, an attempt has been made to determine approximately the extent of ash and sulphur reduction obtainable under given conditions on coal from the mines which were sampled, In the coal-producing districts of Alabama a great deaf of attention has been given in recent years to the problem of improving preparation methods so as to obtain from various coal beds the best possible grade of washed coal. This is especially so where the washed coal is used for the making of metallurgical coke in by-product plants or where there are possibilities of using the coal for this purpose. In the manufacture of metallurgical coke, the sulphur content of the coal is a very important consideration. It is quite often the determining factor as to whether or not a certain coal can be used for coke making. In the studies which form the basis for this report, all samples have been analyzed for sulphur in order to obtain information regarding the possibilities of sulphur elimination as well as ash reduction, and the samples on which reports are made were obtained from beds that are characterized by rather high percentages of sulphur. In connection with the present investigations of coal preparation in Alabama a standardized method of interpreting float-and-sink data has been used extensively for predicting the ash and sulphur reduction and yields obtainable in a commercial washing plant from various sizes of raw coal and from the raw coal as a whole after a certain degree of crushing. This method, which will be explained in subsequent chapters, was used in interpreting the data contained in this report. The samples used for these washability studies were obtained from the following mines in the Warrior field of Alabama: Beltona mine on the Jefferson bed; Dolomite and Mulga mines on the Pratt bed; Coal Valley No. 163 and Coal Valley No. 11 mines on the Corona bed; Cedar Cove mine on the Carter bed.

Jan 1, 1932

By B. W. Candrud

This report, consisting mostly of float-and-sink data and washability curves, has been prepared in connection with an exhaustive study of coal preparation in Alabama conducted by the U. S. Bureau of Mines and the University of Alabama with the cooperation of the different coal operators on the basis of the float-and-sink data, an attempt has been made to deter-mine approximately the extent of ash and sulphur reduction obtainable under given conditions on coal from the mines which were sampled. In the coal-producing districts of Alabama a great deal of attention has been given in recent years to the problem of improving preparation methods so as to obtain from various coal beds the best possible grade of washed coal. This is especially so where the washed coal is used for the making of metallurgical coke in by-product plants or where there are possibilities of using the coal for this purpose. In the manufacture of metallurgical coke, the sulphur content of the coal is a very important consideration. It is quite often the determining factor as to whether or not a certain coal can be used for coke making. In the studies which form the basis for this report, all samples have been analyzed for sulphur in order to obtain information regarding the possibilities of sulphur elimination as well as ash reduction, and the samples on which reports are made were obtained from beds that are characterized by rather high percentages of sulphur. In connection with the present investigations of coal preparation in Alabama a standardized method of interpreting float-and-sink data has been used extensively for predicting the ash and sulphur reduction and yields obtainable in a commercial washing plant from various sizes of raw coal and from the raw coal as a whole after a certain degree of crushing. This method, which will be explained in subsequent chapters, was used in interpreting the data contained in this report. The samples used for these washability studies were obtained from the following mines in the Warrior field of Alabama: Beltona mine on the Jefferson bed; Dolomite and Mulga mines on the Pratt bed; Coal Valley No. 16B and Coal Valley No. 11 mines on the Corona bed; Cedar Cove mine on the Carter bed.

Jan 1, 1932

By D Eschebach, D Mathewson

A belt press filter (BPF) handbook containing practical information for the reference of plant designers and operators has been created as part of Australian Coal Association Research Program project C23040. The handbook combines research and experience with newer generations of equipment and circuitry. BPFs are increasingly finding application in the dewatering of thickener underflow tailings slurries due to changing environmental regulations, difficulty obtaining tailings storage facility approvals and limited water availability. Sources of BPF inefficiency and low availability stem from a lack of understanding of the key operational parameters that affect their performance. This lack of understanding typically leads to increased operational expenditure due to suboptimal reagent dose rates and increased maintenance costs, or decreases in plant availability due to excessively high filter product water contents and equipment failure. It is essential for the continued economically competitive operation of Australian coal handling and preparation plants that complex factors affecting BPF operational performance are clearly defined and understood. Installation and operation handbooks are often provided to sites with new installations, but these manuals are manufacturer- or even model-specific and are often focused on mechanical maintenance. The handbook identifies industry ‘best practice’ and improvements developed by other sites, such as extra spray bars, air system bleed valves, guarding designs, feed and filtrate protection screens and roller tensioning systems. Equations to predict optimum operating conditions – such as free moisture, belt tension and reagent dose rates, with simple feed-specific variable inputs – have been developed from site-specific test work. The correlations developed provide a benchmark for plants to attempt to achieve. This provides operators and process engineers with a tool to explain BPFs and assist them in optimising the performance of BPF dewatering plants of both contemporary and less modern design.CITATION:Mathewson, D and Eschebach, D, 2015. ACARP belt press filter design, operation and maintenance handbook, in Proceedings Tailings and Mine Waste Management for the 21st Century, pp 73–82 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By Grieveson P, Terry B. S

Carbothermic reduction of sulphide minerals for achieving a selective separation of metallic species from complex minerals has been discussed by considering the prevailing oxygen potential during the course of reaction. Construction of univariant plots for the reduction of sulphides with carbon monoxide gas or carbon and in the presence of either lime or anhydrous calcium sulphate is the key feature of this work. The theoretical calculations for univariants in the Cu-Fe-S-O system indicated a preferential separation of metallic copper and iron by imposing a chemical potential. This is evident from a logarithmic plot of sulphur dioxide partial pressure against reciprocal temperature. The results are compared with empirical data for the reduction equilibrium. The reduction behaviour of the constituent sulphides are also discussed together with the experimental results and theoretically predicted phase stability diagrams.

Jan 1, 1992

By Oliver Bowles

The term" sandstone" is applied to a rock composed of mineral grains smaller than pebbles, cemented together more or less firmly. "Conglomerate" is the name given to a rock composed of pebbles, or pebbles and bowlders, of various sizes cemented together. If the pebbles are large and well rounded the rock is sometimes called " pudding stone." Although the term "sandstone" includes all varieties, certain specific terms are applied to types characterized by particular compositions, colors, or uses. "Quartzite" is a variety in which the individual grains are so firmly cemented together with quartz that the rock will fracture as easily through the grains as through the cement; "ferruginous sandstone" is one rich in iron as cementing material, or as grains, or both; "micaceous sandstone" is one in which mica is prominent; " arkose" is a feldspathic or granitic sandstone composed of angular grains; "calcareous sandstone" is one containing considerable calcium carbonate; and" argillaceous sandstone" is one containing considerable clay. The term "flagstone" is used for a rock that splits readily into sheets suitable for flagging; "freestone" for rock than can be cut or carved readily, and with equal ease in all directions; and" ganistel'," in the United States, for sandstone suitable for the manufacture of refractories. Others are named from their characteristic colors such as " bluestone," " redstone," or " brownstone."

Jan 1, 1917

By Kazuhiro Nisizono, Takashi Kuroki, Nobuyuki Mori, Keisaku Ogi

"The improvement of critical current density and mechanical property is essential to the practical application of the superconductive oxides. A solidification technique is developed in this study for the growth of columnar or single Y123 crystal with finely dispersed Y211 and Ag particles through a monotecto-peritectic reaction of Li.(Ba-Cu-Ag-0 rich liquid)+ Y211-+ Y123+Lz(Ag rich liquid). The large solidification rate and temperature gradient can refine the Ag and Y211 particles. But Ag-free region is widely formed along the crystal growth direction in the central part of the Y123 cell. Since this phenomenon occurs because of the cellular growth, it is necessary to narrow Y123 cell width or to grow Y123 crystal with flat freezing interface. By controlling crystal growth direction using a seed crystal, Y123 columnar or single crystal with uniformly dispersed fine Ag particles are obtained. The· behavior of Ag and Y211 particles during the solidification of Y123 crystal is simulated by the peritectic growth model of faceted Y123 crystals.IntroductionY-Ba-Cu-0 superconducting oxide (YBCO) with high critical temperature also has excellent superconducting characteristic under the high magnetic field. The critical current density (Jc) has been enhanced by ·using unidirectional-solidification technique, which can overcome the weak-link problem at grain boundaries and control the crystal orientation and the distribution of Y211 particles which give effective magnetic flux pinning centers in the Yl23 matrix [1-4].In addition to improving superconducting properties, it is necessary to improve mechanical property for the practical application. The silver addition to the melt-textured YBCO superconducting oxide has been reported as the effective method to improve mechanical properties without degrading superconducting properties. Since the material properties are considered to be largely affected by silver particle size, form, dispersion state etc. in the Y123 phase, it is important to control Ag distribution in YBCO/Ag composites. Besides, it is also reported that the silver addition improve the corrosion resistance to the water and CO2 [5,6]. Nishizono et al. [7-9] have reported that the silver distribution in the YBCO/Ag composites is largely affected by the solidification condition, but yet some unclear points are also remained. YBCO has been also fabricated by the zone melting method [10-12], and Furuya et al. [5] and Hirano et al. [13] have reported the fabrication of silver added YBCO composites, but the distribution and behavior of Ag are not investigated in detail"

Jan 1, 2000