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Stamler Corporation manufactures of mining machinery and material handling equipment specialising in Feeder-Breakers to the mining and quarrying industries.

Jan 9, 1996

Discussion of the paper published Trans Inst. Min. E., 1916, vol. li., page 99 comprises a written comment by Bolton H. giving two examples of the faunal evidence for deep-water vs littoral conditions of Goniatites (cephalopods) and Upper Old Red Sandstone fishes

Dec 1, 1916

By Michael Brittan

The AARL elution process has recently been introduced to the North American mining industry by Bateman Engineers Inc. The process is described along with its noteworthy features. Design and operating considerations are discussed.

Jan 1, 1998

By H. H. Evinger, M. Muskat

A methoD of calculating productivity factors for oil, gas, and water systems in the steady state is presented as an illustration of the quantitative application of the fundamental data on the flow properties of heterogeneous fluid systems. While the numerical results of the calculations cannot be applied directly to field conditions, because they are based on permea-bility data for unconsolidated sands and involve specific assumptions regarding the nature of the reservoir fluids, the methods of analysis and interpretation should havc significance in considering certain specific field situations when the necessary field and laboratory data become available. Moreover, it is felt that even under the idealized conditions to which the numerical calculations refer they should serve to give at least the orders of magnitude of the effects of gas-oil ratio and connate water on observed productivity factors. Within the indicated limitations, the computations imply that the foregoing factors can explain only a part of the apparent discrepancy between the homogeneous fluid productivity factors and those obtained recently in field measurements on the West Coast. IntroductioN Sufficient laboratory research has been carried out in the last several years on the fundamental features of the flow of heterogeneous fluids through porous media to call for consideration of what can be done with this type of information. It has, of course, already led to a, much clearer general understanding of the mechanics of oil production. However, examples of the quantitative application of the results of such laboratory studies are few in the literature. part of the explanation for this fact lies undoubtedly in the lack of sufficient laboratory data relating to practical fluids and sand systems such as would occur ill actual oil reservoirs. However, unless it can be shown that if such data were obtained quantitative applications could be made, serious doubt may be cast upon the desirability of carrying on further extensive experimental research work on fluid flow. The purpose of this paper is to present one approach to the problem of quantitative application of laboratory data to practical field problems. Because the published results on the basic experiments with three-phase fluid systems in porous media are limited entirely to uncon-solidated sands, the numerical applications made here will not pertain directly to any actual field situation. However, they should serve to illustrate what could be done with fundamental laboratory data if they were extended to cover the field of consolidated sands. From this point of view, it is hoped it will serve to encourage further laboratory research on this problem. The particular application to be treated here relates to the calculation of the productivity factors for oil-gas-water systems in the steady state. This specific problem seems especially appropriate for discussion in view of the recent publication by Johnston1 of the results of produc-

Jan 1, 1942

By Orville R. Lyons, A. C. Richardson

THE Coal Division of Battelle Memorial Institute, during the course of an investigation conducted for a coal producer, carried out extensive sampling of the fine-coal section of a preparation plant. The information obtained during the testing period was used to evaluate the overall plant operation and provided the basis for. recommended changes in the plant flowsheet. Included in the information were data for the results obtained when using a Bird centrifuge to dewater the particular coal being treated. At the completion of the investigation, the coal producer gave Battelle permission to publish the operating data for the Bird centrifuge in order to make this information available to the coal industry. The authors wish to take this opportunity to express their appreciation to this company and its officials for their willing cooperation in the matter of publication. Description of Preparation Plant: The preparation plant on which the data were obtained is primarily a jig plant. The coal being washed is a low inherent moisture, friable, Pocahontus-type. The washed coal from the jig is dewatered and sized at 1/4 in. by a Parrish-type dewatering and sizing screen. The minus 1/4-in. coal and the underflow water from the shaker screen flow to a sludge tank where, after the coal settles, the coal is conveyed by a flight conveyor into a pump sump. The pump, a 300-gpm sand pump, delivers a mixture of fine coal and water to a Bird centrifuge which produces a dewatered cake and an effluent. At the time when the investigation was made, the centrifuge effluent was returned to the sludge tank and the cake product was mixed with a coarser size of coal prior to loading into railroad cars. The semiclarified water from the sludge tank overflowed into a pump sump from which it was pumped to the jig. As originally designed, the preparation plant was intended to operate with a closed water system but it was found, soon after operations started, that for various reasons this could not be done. In order to provide for removal of excess water from the system and to aid in maintaining the desired minimum percentage of solids in the circulating water, the plant was operated to provide from the sludge tank a continuous overflow of water and fine solids that was sent to waste. The centrifuge feed represents approximately 35 tons per hour of minus 1/4-in. coal in the form of a pulp averaging 38 pct solids. Sampling Procedure: In order to obtain basic data for determining the relationships existing in the fine-coal section of the preparation plant, samples were obtained for: (1) the centrifuge feed, (2) the centrifuge cake, (3) the centrifuge effluent, and (4) the circulating water. The sampling was arranged to start on a Monday, in order to begin operations with a sludge tank full of fresh water, and was continued long enough to allow sufficient time for fine solids to build up within the water system or for a two-day, four-shift operating period. All samples were taken at half-hour intervals except when plant stoppages occurred. After a stoppage the plant was

Jan 1, 1951

By P. E. Fitzgerald, Dana G. Hefley

An apparatus has been developed which permits selective acidizing of producing formations and determination of the relative permeability of a formation by fluid injection. This apparatus, known as the "Electric Pilot," is an electrical fluid-interface locator, the electrical circuit of which is completed when the elec-tcodes in the well are in contact with a conductive fluid, but is not completed when immersed in a nonconductive fluid. Results are given for a number of typical acidizing applications in which the interface locator was used to control the acid. Description of the method used in making a permeability survey and the data obtained are also included. Introduction Early in the development of the acidizing industry it was recognized that one of the most important problems to be solved in the chemical treatment of any well was the determination of what part of the exposed section in the well should be treated and the selection of the technique that would insure treatment of the desired section. One of the first techniques adopted for assisting in proper placement of the acid, which is still widely used, is the method of confining the acid to the producing section by means of a column of oil, which is known as the Carr1 method of treatment, named for its inventor. In the Carr method it is not possible to selectively acidize a specific horizon in a multiple pay zone, so many improvements and modifications of the basic Carr technique were devised to accomplish this result. In order to overcome the possibility of the acid entering an undesirable section at the bottom of the well, organic gel plugs2 were introduced into the bottom of the well, which served to halt the entrance of the treating solution into these zones.3 These chemical gels later liquefied because of bacterial action and were removed from the well with the produced fluid. In fields where a gas cap existed, as in the Goldsmith field of Ector County, Texas) it was imperative that a treating technique be evolved that would confine the acid to the oil-producing zone below the gas cap. By so doing the oil-productive capacity of the wells could be improved without greatly increasing the gas production and this would lower the gas-oil ratio of the well. ~h, technique employed4 to achieve this effect utilized two pumps, one for pumping the chemicals down the tubing, the other to simultaneously force oil down the annular space to confine the acid to the oil pay, thus preventing the chemicals from entering the upper gas-bearing zones. Experience has indicated that gas wells and certain types of oil wells respond better to ''stage treating.'' This technique utilizes the introduction of a certain volume of acid and then allows the well to ''clean up99 before introduction of the next and usually successively larger stages. Where such methods are employed steps must be taken to keep a disproportionate share of the acid from entering the most permeable and previously treated Zones. A special tool

Jan 1, 1944

By N. A. D. Parlee, N. M. El Tayeb

Fe-V alloys with small percentages of vanadium show no deviations from Sieverts' Law up to P~, = 1 atm in the 1600º to 1750ºC region. At somewhat under 8 pct V and up to at least 20pct V, at 1604" and 1661 °C, nitrogen absorption follows Sieverts' Law at low Pn2 values, but deviates from this law beyond critical values of pn2, due to formation of a nitrzde phase of approximately VN composition. The behavior below these solubility limits can be described at all temperatures by the equations: RAO and parlee1 suggested that the nitrogen absorption curve for liquid iron alloys takes the general form shown in Fig. 1 when an alloy nitride precipitate is formed. They showed that the precipitation of 6 titanium nitride from liquid Fe-Ti alloys follows this general scheme and dealt with the general theory involved. Recently, Evans and Pehlke2 reported their research on the precipitation of aluminum nitride from liquid Fe-A1 alloys. Fountain and Chipman's recent paper3 on the precipitation of boron nitride from solid solution contains a fine example of the analogous behavior which they have been studying in the solid state. Researches on the absorption of nitrogen by liquid Fe-V alloys have been described by various authors.1,4-7 Most of this work has been confined to fairly low vanadium concentrations and rather high temperatures because of difficulties variously described as, formation of surface scums, bridging, and so forth. This behavior and the rough thermo- dynamic calculations made by chipman,8 over eleven years ago, indicated that excessively high vanadium concentrations should not be required for vanadium nitride precipitation. It seemed desirable to look for and study this precipitation in order to fill out the thermodynamically interesting nitrogen absorption data on these alloys. EXPERIMENTAL METHOD The general method used was essentially the same as employed by Rao and parlee,1 in which a Sieverts type of apparatus was used and the precipitation of the nitride detected by the "break-point" in the Sieverts' Law line, and by the visual observation of the formation of the new phase on the surface of the melt. There were, however, a few differences in apparatus and technique as described below. The oil manometer used by Rao and parlee' to measure low partial pressures of nitrogen was not employed. The present authors sought to avoid as much as possible the exposure of the liquid alloy to low total pressures of gas during the 6 to 10 hr long runs because of the heavy iron evaporation-loss errors involved. This was achieved, partly by keeping evacuation times to a minimum with fast pumping but largely by the use of two burettes, one for argon and one for nitrogen, and using them to equilibrate the alloy with mixtures of argon and nitrogen rather than nitrogen alone. Each run involved a careful sequence of operations. After melting, de-

Jan 1, 1963

By Marcel Vallée

"Abstract - Traditionally, the emphasis in ore and reserve inventory has been to provide fairly simple definitions and presentations for reporting to shareholders and the investing public. The recent introduction of the mineral resource category aims to take into account the "part of the deposit that cannot yet be produced or extracted legally and profitably." Recent proposals still place insufficient emphasis on relating resource/reserve reporting definitions more closely to the needs of mining and exploration operators for the estimation and inventory of these basic material assets.In most schemes, significant ambiguities and shortcomings remain. These concern the potential economic interest of resources, the concept of continuity which is fundamental to the estimation of volumes, mass and grades, the objectives of the production feasibility study and the requirements of the geology, engineering and economic appraisals leading to it, and the "availability" of the permits required to start mine development. Up to now, no industry-wide formal consensus has yet been reached for any of these steps, nor for reconciliation between successive statements.A resource/reserve inventory scheme is presented here that is based on ISO 9000 principles and the Australasian system. Explicit criteria and transition points are proposed to define resource and reserve. Similarly, appropriate criteria are proposed to classify the three mineral resource and two ore reserve categories, based on geological and value continuity and on the objectives of the feasibility study. This scheme offers a way to develop ISO 9001 certification of resource/reserve estimation procedures for mining operations and supply exploration companies with an appropriate inventory system, to allow better information for the shareholders and the investing public.Résumé - L’objectif des inventaires des minerais et des réserves est, depuis le début du siècle, de fournir des définitions simples et d’ordre général visant les actionnaires et le public investisseur. L’introduction d’une catégorie de « ressources minérales » fournira un cadre tenant compte de la "portion d’un gisement qui ne peut encore être extraite ou exploitée légalement et à profit." Cependant, les propositions récentes de systèmes d’inventaires ne comportent pas des définitions des ressources et réserves qui tiennent compte suffisamment des besoins des opérateurs en exploitation et en exploration minière.La plupart des systèmes comportent des ambiguïtés et des carences. Citons la susceptibilité d’exploitation commerciale des ressources, la continuité qui est au centre de l’estimation des volumes, masses et teneurs, les objectifs de l’étude de la faisabilité de la mise en production, le niveau requis des travaux de géologie, d’ingénierie et d’économique qui y mènent, ainsi que la disponibilité des permis dont dépend la mise en production. Il n’y a jusqu’à maintenant aucun consensus dans l’industrie sur ces points, ni sur des procédures de réconciliation entre les estimations successives.Le système d’inventaire des ressources/réserves proposé ici s’appuie sur la structure ISO 9000 et le système australien. Des critères et des points tournants explicites sont établis pour définir les ressources et les réserves. De même, les définitions des trois catégories de ressources et deux catégories de réserves, s’apparent sur la continuité de la géologie et des teneurs et sur les objectifs de l’étude de la faisabilité. Ce projet offre une voie pour développer les critères de la certification ISO 9001 pour les opérations minières, tout en fournissant un système approprié d’inventaire aux compagnies d’exploration, pour mieux informer les actionnaires et les investisseurs potentiels."

Jan 1, 1998

By J. W. Peirce

Advances in instrumentation now make it possible to measure accurately flaw of such difficult-to-mea-sure liquids as mining slurries. A mass flowmeter, which introduces no restrictions in the line, will measure the mass flow of slurry equal to the volume flow times the mms/unit volume. In the mass flowmeter system a volume flow measurement is electrically multiplied by a density measurement in order to give mass flow. Fig. 1 shows a typical mass flow measuring system. The volume flow is measured by a magnetic flowmeter and the density is measured by a gamma gauge cell, neither of which have any restrictions in the line. Consequently, there is no clogging and no more loss of head than there would be in a similm length of standard pipe. None of the parts extend into the flowing stream and there are no moving parts in the measuring elements. PRINCIPLE OF OPERATION OF THE VOLUME FLOW TRANSMITTER The magnetic flowmeter, which is used for the volume measurement, operates on the principle of a generator (Fig. 2). This principle states that when a moving conductor cuts lines of force in a magnetic field, a voltage is induced in it. Moreover, if the dimensions of the conductor remain constant, then the induced voltage is directly proportional to the velocity of the conductor. Since the voltage is strictly a function of flow velocity, the transmitter output can in no way be influenced by such factors as temperature, viscosity, turbulence, or conductivity. The linear output is detected by flush mounted electrodes (as shown) and transmitted to a potentiometer flow receiver. Magnetic Meter Construction: The metering tube is constructed of nonmagnetic stainless steel. (See Fig. 3.) To prevent shortcircuiting of the generated voltage, the tubes are lined with a suitable liner, depending upon the corrosive, erosive or other properties of the liquid or slurry to be measured. A uniform magnetic field is produced by two saddle-shaped coils of insulated copper wire. A laminated iron core focuses the magnetic field at a 90' angle to the flowing liquid. The voltage generated by a flow of liquid through the magnetic field is detected by two point electrodes mounted flush with the inner wall of the metering tube, 180' apart. Electrodes are made of Type-316 stainless steel or other material suitable to the application . Volume Flowmeter Operation: The millivolt output of the metering transmitter is transmitted to a potentiometer-type receiver (Fig. 4). The self-balancing, self-standardizing receiver has a drive unit for circuit rebalancing. The measurement change imposes an unbalanced input on the twin windings of the drive unit. The resulting unequal pull on a segmental rotor provides the motion which drives a pen, while simultaneously and steplessly repositioning a rebalancing element. Changes in conductivity have no effect on the accuracy of the measurement or the calibration of the instrument. The minimum conductivity values are determined by the length of the transmission cable and the size of the transmitter. They can be as low as five micro mhos, since there is such a small load on the electrodes. Because the meter electrically averages all of the incremental velocities in an irregular flow profile, it is ideally suited for turbulent flow and suspended solids. Straight runs of pipe are therefore not required. The transmitter can be installed close to

Jan 1, 1962

By James J. Wise

INTRODUCTION One basic design feature utilized in all caving and sublevel stoping techniques is the drawpoint. These draw- points may be located on sublevels when using sublevel caving methods, or may be located at the floor pillar when using block caving, sublevel stoping, or vertical crater retreat methods. How the drawpoint is designed and developed, how the ore is withdrawn from it, and how the ore is hauled to the shaft or portal encompasses the loading and hauling function. Historically, predominate loading and hauling equipment for caving and sublevel stoping has been scraper slushes, air powered overshot loaders, and rail mounted train haulage. All of this equipment has two common constraints. 1. The equipment locked into specific work sites and is not easily shifted to another work site. This constraint can often lead to low utilization and low productivity of the equipment. 2. The equipment is designed to work in the horizontal plane, which requires that the various horizontally-oriented working levels be connected by vertical raises. Vertical development by means of raises is not only increasingly expensive, but also is not well adapted to movement of large equipment into the s topes. In the last 20 years, two revolutionary labor saving concepts have become common in caving and sublevel stoping. 1. Long-hole drilling, which has mechanized the development of the drawpoint extraction structures as well as the actual stoping and undercutting. 2. Vertical access by means of trackless ramps between levels, and the consequent use of rubber-tired vehicles not only for loading and hauling ore, but also for the rapid movement of men, material, and equipment into the stopes. The introduction of trackless mining systems for loading and hauling has not been easy. Mine planners have had to re-orient their thinking to the larger operating space required by trackless equipment. Larger access drifts have necessitated reconsideration of mine layouts to insure proper ground support. Spiral ramp developments were often laid out on slopes steeper than the equipment could negotiate economically. Mine operators had to accept the added responsibility of roadway maintenance, water removal, increased ventilation, and more technical mechanical maintenance. As the mine operators enthusiastically embraced the superior productivity of trackless mining systems, they some- times disregarded opportunities to combine the older types of equipment with trackless vehicles to maximize productivity at lowest cost. In order to gain a proper perspective on this problem, it is necessary to review the various techniques of loading and hauling and to become more aware of the advantages or disadvantages that each system or combination contributes. LOADING Loading consists of two functions, (1) primary loading from a drawpoint and (2) secondary loading into long- haul system, a truck, train, or possibly a belt conveyor. Mine planners have four basic loading systems available to fit various operating conditions. These are, (1) gravity, (2) scrapers, (3) rail-mounted loaders, and (4) trackless loaders. Each system can produce optimum results under specific conditions. Gravity Loading Gravity loading is probably the oldest system in general use today.

Jan 1, 1981

By E. P. Chen

This investigation involves the development of a two-dimensional continuum model for the description of jointed media. Specific application of the model developed here is for the potential geological disposal of radioactive waste in the layered sequence of fractured volcanic tuffs under Yucca Mountain, Nevada. This is currently being considered by the Nevada Nuclear Waste Storage Investigations Project, administered by the Nevada Operations Office of the U. S. Department of Energy. The work is a direct extension of the previous constitutive model by Thomas (1982) based on the work of Morland (1974). The main feature of Thomas's model includes two parts: a continuum approximation based on average discontinuous displacements across jointing planes within a representative elementary volume, and a material constitutive description based on linear elastic matrix material behavior and nonlinear normal and shear joint behavior between jointing planes. The mathematical descriptions by Morland based on strain partitioning among matrix material and joint sets allow multiple joint sets to be included in the model. However, the initial effort by Thomas to implement Morland's mathematical model included only a single set of joints. To make the material model reflect more realistically the field characteristics, the current work extended Thomas's model to include orthogonal sets of joints. The nonlinear elastic normal joint behavior is retained in the present model. Joint shear response was treated as linear elastic in the shear stress versus shear displacement relationship prior to attaining the stress level governed by the Coulomb friction criterion. Beyond this critical stress value, a horizontal line is assumed in the work of Thomas for the shear stress versus slip displacement relationship such that the shear stress remains constant while the slip displacement increases. Motivated by experimental observation, the current work generalized the shear response to allow a line with finite slope to govern the slip behavior beyond the critical stress level. The inclusion of an orthogonal joint set led to a fourth order algebraic equation for the calculation of stress increments as compared with a second order equation obtained by Thomas. The nonlinear elastic normal joint behavior provides criteria which allow the selection of the root that yields result consistent with the loading condition of the problem. The addition of one more set of joints provides the potential to more completely study the interaction of various parameters representing the characteristics of jointed media behavior. Material responses to various loading conditions based on the present constitutive model have been obtained. These results and their comparisons to single joint set results are presented. Formulation of the Continuum Model The inclusion of an orthogonal joint set led to a fourth order algebraic equation for the calculation of stress increments as compared with a second order equation obtained by Thomas. The nonlinear elastic normal joint behavior provides criteria which allow the selection of the root that yields result consistent with the loading condition of the problem. The addition of one more set of joints provides the potential to more completely study the interaction of various parameters representing the characteristics of jointed media behavior. Material responses to various loading conditions based on the present constitutive model have been obtained. These results and their comparisons to single joint set results are presented. Let us focus our attention on the set with normal n first. Let the jump dilation displacement and jump slip dasplacement associated with the [ ]

Jan 1, 1986

By G Solly, P J. Leevers

Day-to-day operating practices at existing operations need provide high quality data for decisions that will impact directly on the potential value of the available resource, in addition to meeting standards of quality expected of data used in feasibility studies that will be completed to obtain additional capital required to finance operational improvements. Drill hole location, down hole survey and assay data standards of accuracy and precision have received considerable attention in recent years. The authors propose that geological descriptions of both cored and non-cored drilling warrant at least equal attention, considering their fundamental role in establishing the framework used for geological modeling and resource estimation. The iron ore deposits of the Middleback Ranges have been a major source of iron ore for almost a century. High-grade hematite-dominant ore is currently mined by OneSteel from three open pit operations supplying ore to the companyÆs integrated steelworks at Whyalla. A review of OneSteelÆs future iron ore resources, commenced in 2002, highlighted the need for more flexible and comprehensive management of all forms of geological data used in resource evaluation. Driving this program was the information needs of feasibility studies of the Iron Magnet deposit, located beneath the existing Iron Duke and Iron Duchess mines. Prior to the beginning of 2003, resource evaluation drilling data collected by OneSteel was managed using an in-house system based on industry standard relational database software. The system was demonstrably effective in ensuring the fundamental integrity of basic drilling data, but lacked necessary capabilities for the acquisition and management of geological descriptions, geotechnical and geophysical data obtained by down-hole logging. OneSteelÆs existing system for the management and interpretation of geological descriptions was restricted to storage of a single three digit code for each lithological description interval. The original logs for a large number of older drill holes could not be located, having been either poorly archived or culled from the database in the belief that they did not contribute to the understanding of the resources currently being mined. The three digit codes represented a combination of lithological and stratigraphic descriptions, including many subtle variations in iron ore colour and texture believed to be associated with variations in geochemistry, but subsequently demonstrated to be either incorrect or inconsistently applied. This resulted in the establishment of a plethora of codes for a relatively small number of distinct lithologies. Improvements implemented by OneSteel geologists addressed these shortcomings by ensuring the new data management system: facilitated the objective description of lithological characteristics; distinguished between obsevations and interpretations (eg lithology versus stratigraphy); promoted consistency between descriptions provided by different geologists; and helped to ensure data integrity by developing an audit trail for alterations made to data subsequent to its acquisition. The data used to develop interpretations of mineralisation distribution and characteristics are fundamental to the effective utilisation of a mineral resource: any mineÆs most important asset. Resource related risk is widely recognised as the principal source of technical risks affecting resource development projects, whether they are new mines or expansions of existing operations. A key lesson from this work is that most commercial or æin-houseÆ developed geological data management systems are able to handle basic data validation tasks effectively. Geologists, however, need to ensure that the data management system is appropriately structured to help promote the acquisition of objective and consistent data for interpretation.

Jan 1, 2003

By Mance G

Today there are many different techniques of soil remediation used in Australia and throughout the world. This paper considers the thermal desorption remediation technique and, in particular, the application of high temperature filtration to the process. The thermal desorption technique involves the treatment of hydrocarbon (oil, petrol, etc) contaminated soil. The process involves heating the soil in a retort or kiln to drive off the volatile organic contaminants. The exit gas stream from the retort is subsequently passed through an after burner to thermally oxidise the hydrocarbons. This technique produces soil and combustion gas streams which are free of hydrocarbons. Due to the heating and agitation of the soil within the retort, soil particles become entrained in the hot gas stream. To avoid the blockage and fouling of the system's interim ductwork and the afterburner, high temperature filtration technology has been applied to remove these soil particulates without cooling the gas Stream.

Jan 1, 1995

By J. W. Hickman

INTRODUCTION RECENT work by the authors1 on the oxide films formed on alloys of titanium and zirconium with nickel and copper indicated that an investigation of the oxides which form on alloys of copper and nickel might permit the relative rates of formation and diffusion of the ions of. these metals to be determined. This binary system is of further interest since the alloys which form are of the solid solution-type over-the entire range. In addition nickel is much more oxidation resistant than copper. A comparison of the free energies of formation of the simple oxides which may occur on these alloys indicates that nickel oxide should be observed over the entire time and temperature ranges of oxidation for all alloy compositions.1 In. order for nickel oxide to predominate on the surface, it is necessary that nickel ions form and diffuse to the surface. Two factors which may influence the formation of nickel oxide may be the ionic sizes, where Cu+ is 0.96Å and Ni-++ is 0.70Å, and the charges on the ions. On the basis of size, Ni++ should diffuse more readily than Cu+ while on the basis of charge, Cu+ should form more readily than Ni++. According to Uhlig2 passivity to corrosion in an alloy appears at a critical composition which for copper-nickel alloys is related to the tendency of the d band of electronic energy states to fill with electrons. This composition in the copper-nickel alloys corresponds to 40 at. Pct nickel at which composition Uhlig2 (quoting La Que's data) states that the alloy system becomes passive. Magnetic and specific heat data indicate that the d band of copper-nickel alloys is filled at 6o at. pct copper or 4o at. pct nickel. Mott and Jones3 have shown that if, on alloying nickel with copper, one considers a copper atom to be identical with a nickel atom except for an extra electron (nickel -has the-configuration: 3d8 4s2 and copper: 3 d10 4s) then at 60 at. pct copper or 4o at. pct nickel enough electrons are contributed by copper to fill the d band of the alloy. At this composition the magnetic susceptibility approximates zero according to Grew.4 Although the electron diffraction data will not determine the rates of the several reactions which may occur during oxidation, yet a determination of the structures of the surface oxides may yield information concerning the relationships, if any, which may' exist between the oxide structures which form and that composition where the magnetic susceptibility approximates zero. It is quite possible, of course, that the mechanisms of the oxidation and corrosion reactions may be so widely different that no correlations between them may be possible. SURVEY OF LITERATURE The metals, copper and nickel, which are face-centered cubic, form solid solution alloys which are face-centered cubic with no superstructure for all compositions. Three oxides of nickel have been investigated structurally by X ray diffraction. Of

Jan 1, 1948

By J. DeYoung

Weak demand for metals and consequent low metal prices resulted in continuation of the depressed state of US mineral exploration activity through 1983. Data collected by Resources for the Future Inc. and The Pennsylvania State University for a cooperative study on mineral exploration activity indicate that US exploration in 1983 fell by as much as 25% from 1982 levels. Precious metals remained the focus of most exploration efforts, as gold and silver prices remained attractive compared to base metals. Reports of 1983 domestic exploration and development activities in several industry journals indicates that about 85% to 90% of those projects were directed primarily at gold and silver. Gold exploration included work by several companies on Carlin- type disseminated gold deposits in Nevada, geological prospecting and drilling in the Wenatchee Gold Belt in Washington, and interest in lode and placer gold properties in California, especially by several small Canadian firms. Precious metals exploration projects were also reported in Alaska, Arizona, Colorado, Montana, New Mexico, Oregon, South Dakota, and Utah. There was also tome precious metal exploration activity in the eastern US. Development continued at the Ropes gold mine near Ishpeming, MI, and companies explored historic gold-producing areas in the Southeast. Some exploration for nonprecious metals took place last year. Stratabound copper-silver deposits were examined in western Montana, and US Borax continued exploring molybdenum resources in the Misty Fjords area in Alaska. Work on these projects during 1983 may have been stimulated by time limits on the availability of certain federal lands for exploration more than by projected improvements in metal markets. During 1983, several papers were published on mineral exploration strategies and the future of US exploration. David Watson of Raymond Kaiser Engineers, in a paper presented at the 1983 AMC Mining Convention, forecast increased exploration activity for gold and silver because of world economic conditions. He added that antimony, manganese, chromium, graphite, mercury, tantalum, tin, and barite are also likely targets based on their limited domestic reserve availability. He cited concern over reported subsidized mineral production by foreign producers and US regulatory and land-planning policies as retarding mineral exploration activity. Douglas Cook of Freeport Exploration Co., at the same meeting, presented a paper that showed that a 1950-75 period of vigorous exploration has been followed by a period where acquisition has replaced exploration as the predominant means of acquiring new mineral properties. At a December IIASA conference on "The Economics of Mineral Exploration," in Vienna, Austria, A. Rose and R. Eggert of The Pennsylvania State University pointed out that recent exploration decisions tend to rely more on evaluating production costs and comparing them with existing deposits, rather than on return of

Jan 5, 1984

By Winthrop P. Haynes

The symposium on production for the year 1944 includes more foreign papers than any one of the past three years, because of a partial relaxation of the censorship in many Western Hemisphere countries. The committee was not successful, however, in securing papers from Europe and the Near and Far East at this time, with the exception of Saudi Arabia and Bahrein. Where possible, these papers include summaries upon production for the missing war years, so that we shall have no permanent gap in the records. At the close of the war, we hope again to publish the usual more complete form of report for all important oil-producing countries. EXCERPTS FROM CIRCULAR TO AUTHORS In order to facilitate interpretation of the data in this chapter, we print the following excerpts from the Circular to Authors. The field is the unit in this tabulation. In cases of fields extending across State boundaries, such as Rodessa, it is suggested that each State author treat the section of the field in his State as a unit, and by a footnote indicate that the field extends into an adjacent State. Each place in the table may represent one of three possibilities; either the proper entry is determinable and can be supplied by the author, or an approximate figure can be supplied which is the author's best guess and should be entered followed by an x, or it does not apply to the particular field and the space is left blank. Contributions of great value may be made by the author in many cases where entries are not subject to precise determination. In such cases the author should use his good judgment and make the best entry possible under the circumstances. The entry of a zero is a positive declaration, and it is an important declaration where it is in order. It is thought that the nearest whole numbers are sufficiently accurate for our purposes except as to percentage of sulphur in oil. If an author desires to report any other figures to tenths, he may do so. The quantity of gas produced should include, where possible, gas sold or otherwise marketed, and gas blown into the air, burned as flares or otherwise wasted. Segregation of these figures would be interesting if the authors can make such segregation. In any event, the figures should represent as nearly as possible the total quantity of gas removed from the reservoir. . Under the columns on "Depth," the average depth to the top of the productive zones and to the bottom of the productive wells, when subtracted, should give the approximate thickness of the productive zone. For fields where this is not true because of unusually high dip or for some other reasons, it is suggested that the authors indicate in their text the approximate average thickness of the productive zone. The net thickness of the producing formation should be the thickness of the producing zone, less the estimated amount to cover the portions of the zone that do not yield oil, such as dense shales, etc. It is recognized that for some fields the authors can only make rough guesses; in such cases, they should enter their best estimate followed by an x. Average production per acre-foot need not be reported as it can

Jan 1, 1945

By Jung-Keuk Kang

Recently, the Korean government prepared a strategy for deep seabed mining, which consists of three stages for 20 years until 2010. The first step of the program is focused to conduct deep seabed exploration until 1993. The apparent "hurry-and-spend to catch-up" policy that the Korean government has shown in deep seabed mineral exploration was motivated by an effort to qualify a prerequisite requirement to be a pioneer investor as a developing country under the terms of Resolution II and the New York Understanding. Since 1983, KORDI (Korea Ocean Research and Development Institute) under the auspices of the Korean government has carried out deep seabed mineral exploration. The KORDI had a joint exploration program with USGS from 1989 to 1991 aiming to evaluate the potentiality of manganese nodule in the western part of Clarion-Clipperton Zone as well as that of manganese crusts in the western Pacific. In 1992, Korean government accelerates its program by the confirmation of national policy and the equipment of new built research vessel, Onnuri-Ho. The RIV Onnuri-Ho is about 1400 G/T, which is equipped with various advanced instruments including GPS, multi-beam echosounder (Seabeam 2000), multi-channel seismic system, and MDM system.

Jan 1, 1992

By W. R. Finlay, W. R. Jr. Hibbard

The key feature of the lattice coherency theory of precipitation hardening1 is the forced coherence between matrix and precipitate which elastically strains both lattices and is believed to be the major source of strengthening in precipitation hardening. In systems exhibiting age hardening, the atom movements leading to precipitation are not at all extensive and are such as to require the minimum amount of energy to produce the interface; that is, the new lattice forms in such a way as to be as nearly as possible a continuation of the old with a matched, coherent plane at the interface at least during the initiation of the precipitation. The crystallographic sequence whereby regions of the matrix change to the precipitate lattice usually can be resolved into a set of shearing operations.6'6 Conversely, the perhaps novel speculation is made that solution of a second phase is accompanied by shearing movements which are possibly the reverse of the precipitation shearing movements. A basic premise of the investigation reported in this paper is that precipitation and solution shearing movements constitute structural weaknesses which might cooperate with applied stresses to facilitate plastic deformation. Another basic premise of the investigation is that the application of hydrostatic pressure to a precipitation hardening system will significantly alter the degree of disregistry across the matrix-precipitate interface and thereby significantly affect the course of age hardening. Two binary precipitation hardening systems were investigated: rz pct zinc in aluminum which undergoes transformations, both precipitation and solution, by a simple crystallographic mechanism; and 4 pet copper in aluminum which undergoes a complex transformation in precipitating and dissolving a second phase. The effects of the application of uniaxial tensile creep stress during elevated temperature aging of both systems and of hydrostatic pressure during the elevated temperature aging of 12 pct aluminum-zinc were then investigated. Previous Investigations Van Wert in 1935,~ studied the effect of hydrostatic pressure on the room temperature age hardening of a few precipitation hardening systems. The latter were rather unfortunately selected since none is known to exhibit any marked volume change on aging and the majority were complex commercial alloys the precipitation mechanisms of which are not known. Jenkins, Bucknall and Jenkins~n,~ in 1944, applied tensile creep stresses to a complex copper. nickel-silicon alloy at various temperatures. The complexity of the alloy and the industrial objective of the work did not permit an appreciable addition to the theoretical understanding of either deformation or precipitation hardening.

Jan 1, 1949

By J. O. Roux

The Impala Platinum Limited Base Metals Refinery in Springs, South Africa, refines convertor matte containing base metals and PGM?s (platinum group metals) using a hydrometallurgical process. In addition to a PGM-rich concentrate that is further refined, the Base Metals Refinery produces nickel (in powder or briquette form), copper cathodes and cobalt powder. Five leaching stages are utilized to remove the base metals and impurities from the PGM concentrate. The project described in this paper involves a radical redesign of the second stage leach autoclave with the aim of reducing maintenance costs and downtime, increasing throughput and ensuring a safer working environment. The second stage leach process at the Base Metals Refinery, produces a PGM-rich residue through the extraction of copper and any remaining base metals from the first stage leach solid residue material. Leaching is performed in an autoclave operating at a pressure of 600 kPaG and a temperature of 140°C to 150°C. Concentrated H2SO4 is added to the feed to produce a solution with a free acid content between 10 and 30 g/L and a pH of less than 2. Oxygen is passed into the 1st and 2nd compartments of the autoclave. As a result of the aggressive, highly oxidizing conditions within the autoclave, the original design utilized a heavy wall carbon steel shell with lead lining and two layers of acid bricks. The bricks acted as a wear resistant material and ensured a low surface temperature at the skin of the lead lining, whereas the lead lining acted as a corrosion barrier to protect the steel shell. These brick lined autoclaves were heavy, maintenance intensive and prone to catastrophic failure. A radical autoclave redesign was needed to reduce the high costs of manufacturing, installation and operation. Finite element modelling was used to optimize the design and various high alloy materials were investigated for the application. Based on extensive test work, the carbon steel shell was replaced with duplex SAF 2205 stainless steel in the new design. The use of this highly corrosion resistant material, eliminates the need for the lead and brick linings and reduces the wall thickness requirements substantially, resulting in an increase in the available volume for the same external shell dimensions. The vessel is welded in circular sections to form an elongated, impermeable, cylindrical body, with several agitator nozzles and compartments. The first new duplex stainless steel unit has been in continuous operation for more than 24 months and its performance has exceeded the highest expectations. The design was so successful that a patent has been registered. The major benefits of the new stainless steel design include increased throughput, improved performance, less downtime and a safer working environment. Lead has been eliminated and replaced with a more environmentally safe material, and the total lifespan of the vessel has been extended. In addition, the autoclave project has made significant developments in advancing the field of welding and optimizing the integrity of welding quality standards in South Africa.

Jan 1, 2009

By J. W. Leonard

Introduction Gravity-based coal/mineral preparation plants must be operated to yield products of a quality satisfactory to existing markets. However, because of historic control problems, recovery is frequently sacrificed to achieve quality, resulting in losses of valuable product. Plant control has ranged from intuitive in-plant spot quality judgments made by various operators to gross methods involving such devices as density gauges, floats, grabsample on-the-spot sink/float tests, etc. Millions of tons of quality coal/minerals are lost to refuse each year, because of the historic lack of a continuous and dependable control system. The result is serious economic, as well as environmental, losses. While the economic losses are obvious, the less obvious environmental ones, in the case of coal, result from the misplacement of more ignitable quality fuel to refuse banks. Until recently, a control system capable of supplying a market-grade coal/mineral product, while continuously minimizing product losses to refuse, has been technologically unavailable. Coal/Mineral Washing Tracer System Performance Monitor (CMWTSPM) The first Coal/Mineral Washing Tracer System Performance Monitor (CMWTSPM) originated in the late 1970s as an innovative idea and ultimately resulted in Leonard Patent No. 4,345,994 issued on August 24, 1982. In a classic example of successful university basic research, the patent was followed by two US Department of Energy (DOE) merit awards for fundamental optimization research at the University of Kentucky, a number of publications, a successful applied research program (underwritten by SENTREX at Irvine, CA) and field tests at the Rochester and Pittsburgh Coal Company Keystone Mine near Indiana, PA. The system is now operational and is marketed by SENTREX as the SENTREX Performance Monitor. A diagram of the system is shown in Fig. 1. This system relies on metal detection as the basic tracing medium. Since it is capable of tracing particles as fine as 0.19-in., the system is ideal for coarse coal/ mineral cleaning processes. Basically, the CMWTSPM records the distribution of synthetic coal/mineral particles, of known size and specific gravity, between product and refuse output streams of coal/mineral washing, gravity-concentrating processes. For any given particle size, surface area and shape are constant. The particles are [ ] designed to find their way into the center of their respective inprocess specific gravity/size streamlines. The system will yield a complete partition curve to show the percentage of misplacement for any selected size/specific-gravity particle fraction, thereby providing a point-to-point insight into process failure. When used to evaluate operational processes, this full partition curve is far more diagnostic than the simplifying, derivative, single index number known as the Ep value. The Ep value is commonly used for convenience to represent symmetrical partition curves, but, if the actual partition curve is non-symmetrical, use of the Ep value can result in serious diagnostic error. While the Ep is useful in design and for rapid performance evaluation and process adjustment, the full partition curve is by far the more diagnostic. It will provide insight into the behavior of particulate flow, through non-symmetry, as a means to highlight potential systemic failures. Performance of the process is measured and improved by determining the extent of particle misplacement and by making timely adjustments to the unit to reduce the misplacement. Used in this manner, the CMWTSPM is not only a long needed processing control monitor, but it is also a very powerful diagnostic tool which, in the hands of skilled operators, has

Jan 1, 1993