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By Frank H. Macpherson

FEW people realize the tremendously important part that Saline and Pulaski Counties in central Arkansas have played in the winning of the war. The present favorable war situation might have been very different if we had not had the bauxite produced during the past two years from these two small areas, a total of about 15 square miles. As a general statement, it can be said that the Arkansas bauxite deposits are, individually, relatively small, irregular in thickness, somewhat scattered and, therefore, compared with coal or iron-ore or open-pit copper deposits, relatively ill adapted to a rapid and drastic expansion in output. A few years ago it would have seemed an impossibility for these two counties to produce over six million long dry tons of bauxite in one year. However, with the cooperation of the operators, that is what happened in 1943, when the state of Arkansas achieved the seemingly impossible with a production of 6,020,684 1 long tons (dried equivalent) of bauxite ore during the calendar year, compared with an average annual production of 323,725 2 tons in the period 1931 to 1941. It became apparent early in the year 1941 that the United States soon might be drawn into the war, and, therefore, that an immediate study of the domestic metal situation was necessary. Aluminum is by far the most important metal used in the manufacture of aircraft and many other implements of war and it was evident that there would have to be a tremendous increase in the domestic production of bauxite, which is practically the only present source of this metal. As more than 95 per cent of the known bauxite reserves of the United States was in Arkansas, careful preliminary studies were made in that state by representatives of the United States Bureau of Mines, the United States Geological Survey and the War Production Board in the summer of 1941. Reserves in other states also Were studied. The result of these studies was a recommendation by the War Production Board that mining in the bauxite-producing areas of Arkansas be geared for maximum production, in order to supply sufficient ore for this country's war requirements and, if necessary, to supply the war needs of Canada as well. The annual goal of eight million long tons (dry Weight) set for Arkansas by the War Production Board Was exceeded in 1943, when in August the output reached a rate equivalent to more than 8,300,000 long tons, dry basis. Because of the comparatively small tonnage of bauxite reserves, Congress appropriated funds for an extensive drilling program to be carried out by the Bureau of Mines in cooperation with the Geological Survey. Drilling began in May 1942 but owing to delay in delivery of drills, and trucks upon which the drills were mounted, the program did not get into peak operation until early in 1943. By the end of July 1944, the Bureau of Mines records indicated an addition to the Arkansas reserves of 10,000,000 long tons (wet basis) in place

Jan 1, 1945

By Álvaro Ordoñez

"El amoniaco es un agente acomplejante de iones cobre, que se ha utilizado en diversos procesos para recuperar el cobre de sus minerales. En este sentido, el presente texto propone la utilización del hipoclorito comoagente oxidante en medio básico, con solución de una sal amónica y que se desarrolle en condiciones normales de presión y temperatura, donde un control adecuado del pH permite la formación del amoniaco en cantidades suficientes que permitirá sostener en solución a los iones cobre. Es decir, es posible lixiviar concentrados de cobre que contienen calcopirita y reducir la formación de la película de óxidos de hierro sobre la superficie del mineral a través del uso de amoniaco. "

Sep 14, 2009

By George Burgess

I. INTRODUCTION THE suggestion has often been made that it would be highly desirable, at least for certain grades of steel, to be able to control more certainly, by pyrometric measurement or otherwise, the temperatures of the operation of the open-hearth and other furnaces used in the manufacture of steel and iron. That the properties of the ingot and finally of the finished steel product are intimately related to the final temperatures attained by-the metal inn the furnace and to the temperature of casting, has been recognized by metallurgists for a long time, and this question has been very thoroughly treated, especially by Prof. Henry M. Howe, and by A. W. and H. Brearley.1 It is the object of this paper to demonstrate that in so war as casting temperatures of furnaces, steel ingots, and similar operations involving the temperatures of streams of iron and steel are concerned, well-known pyrometric methods s may be easily applied-if certain recently determined corrections are made and precautions taken-with a relatively high degree of accuracy. Greater but not insurmountable difficulties will be encountered in. the case of open-hearth furnace temperatures, while for" those of the converter type a ready solution does not seem practicable. It appears that certain essential data have always been lacking in reporting observations such as those of Le Chatelier in 1892. Thus the correction to be applied for the characteristic radiation-or emissivity¬has hitherto not been adequately taken into account nor the limitations of the several possible pyrometric methods clearly recognized.

Jan 2, 1917

By J. H. Hodgson

"Those of us who have been concerned with the problem of geophysical exploration in southwestern Ontario have followed the development of the Poulter method with much interest. I have much appreciated the opportunity of reading an advance copy of Dr. Poulter's clear exposition and of preparing the following brief remarks on the probable applicability of the method to the Palaeozoic area of southwestern Ontario.During the years 1944 to 1946, the Ontario Department of Mines, in co-operation with the Union Gas Company and the Dominion Natural Gas Company, operated an experimental party in the hope of establishing a seismic technique appropriate to the •area. The results were completely negative. During two summers' field work, no reflections whatever were obtained except in one area near Windsor. It is the •purpose of these remarks to inquire whether Dr. Poulter's techniques might yield favourable results.It was the conclusion of the report on our work that two principal causes contributed to the failure of the method. In the first place, the geological column possesses few elastic discontinuities and those that exist appear to have low reflection coefficients. In the second place, the area is drift-covered in general. This drift complicates the situation by absorbing seismic energy and by giving rise to groups of complicating refracted phases which obscure the entire interesting section of the record. The situation is further complicated by the high reflection velocities and the relative shortness of the Palaeozoic section, these factors combining to bring in a reflection from the basement in about half a second."

Jan 1, 1950

By Brandon H. Grove

In Austria's only producing field, at Zistersdorf, Erdoel Produktions-gesellschaft completed a single new producer, its well Gosting 6 coming in early in October for an average production of about 15 tons daily. For further testing within the proved part of the field this company's Gosting 7 was at the close of the year drilling in Pannonian strata at 760 m., and its Gosting 8 was rigging up. Outside of the proved area of the Zistersdorf field two further tests located on the Steinberg dome failed to find production in the known oil-bearing strata of the Sarmatian, and were deepened as wildcats into the Cretaceous Flysch. The first of these, Neusiedel 1, about one kilometer north of the known producing area, found oil in the Flysch beds at a depth of 1290 m. for an initial production of about 10 tons per day. The second test, Windisch Baumgarten la, is an old well previously considered a failure, which when deepened achieved a production of about 5 tons per day in the Flysch Inoceramus beds at 985 m. Neither of the foregoing wells is producing from a stratigraphically definable horizon, oil accumulation in the Flysch of this area being apparently controlled by tectonic breccias or related crevices.

Jan 1, 1937

By G. L. Hundley, R. E. Mussler, D. H. Yee, F. E. Block, R. S. Olsen

An anhydrous chlorination process for the recovery of copper from chalcopyrite was investigated. Pelletized concentrate was reacted continuously with gaseous chlorine in a vertical shaft reactor at 550° and 650°C. While the copper was withdrawn with the rest of the metals as molten chlorides from the bottom, 99-x% sulfur was distilled from the top of the reactor. The molten metal chlorides were pulverized and dropped continuously into an upward flowing stream of oxygen. Over 80% of the iron chlorides were converted to oxides in a vertical free-fall reactor at 800° and 900°C while the copper chlorides passed through unoxidized. Copper was recovered in powder form by electrowinning continuously from chloride solutions using a diaphragm cell. The product sloughed easily from a titanium cathode and showed no iron contamination. Current efficiencies and power consumptions averaged 77% and 1.24 kw-hr per lb.

Jan 1, 1974

The Henty Gold Mine is a good example of a situation where conditional simulation and optimisation techniques may have useful impact on modelling of mineralisation distribution and ore definition. Much of the gold mineralisation at Henty is concentrated within an alteration zone which is both physically discontinuous and forms only a small fraction of the overall mineralised volume. The alteration units are mappable from diamond drill core and underground workings. Conditional simulation and optimisation techniques for ore definition have found considerable success in the open pit gold mining environment. For many reasons including computational efficiency, lack of consistent geological information, and lack of familiarity with ideas and methods among mine geologists, implementations of these methods in open pit mining have been comparatively simplistic. Modelling is commonly reduced to treating the sample data as a single geologic population. This paper discusses the application of the MP method (a particular implementation of conditional simulation and optimisation) to modelling the distribution of potential ore blocks in the Henty gold mineralisation. The approach allows the mine geologist to model both the spatial geometry of the alteration types and the gold grades associated with each alteration type in a single process. Options allow the geologist to include or exclude underground geological mapping and face sampling depending mainly on the abundance of drill hole sampling and the quality of the face sampling. An optimisation algorithm based on maximisation of profit from mining is used to assist in ore definition.

Jan 1, 2000

By Wallace W. Wilson

It scarcely 1s possible to read a new issue of any of the principal mining trade journals without noting some mention of a major new overseas mining venture with which one or more domestic companies are involved. These projects seem to follow a fairly consistant pattern; most are large open pit mines, with relatively low grade ore bodies but huge reserves; the total price tag will be in nine significant figures and around half or more of the total cost will be for infrastructure. West1 noted that nearly $7 billion is being invested annually for new mining projects and the expansion of existing mining ventures, in the free world. He anticipates that by the year 1975 such investments would reach the $10-11 billion annual figure, and that in the five year period 1972-76 total capital requirements can be expected to aggregate around $45 billion. The proportion of this total investment which will be financed in some manner is difficult to estimate because of the variety of available financing arrangements. West estimated that around 75% of the total capital would come from internally generated funds, with the balance from external sources. Conceivably a substantially higher percentage could be attributable to external financing, especially it the trend of recent mineral development in Canada and Australia is any criterion, and of course, including local sales of equity as a part of the package.

Jan 1, 1973

By Yoginder P. Chugh

Effects of moisture absorption on the behavior of the Dykersburg shale overlying Harrisburg coal seam in Southern Illinois are presented in this paper. Cylindrical samples of the shale 2.5 cm in diameter and 5.0 cm long were studied for weight gain and swelling strains at 90, 95, and 100 percent relative humidity and under immersed water conditions. After attaining equilibrium conditions, the samples were studied for changes in the strength and deformation behavior. The depth of moisture penetration was measured using the Vickers microhardness measurements. Using the basic mass transfer concepts, effective diffusion coefficients were computed for the shale.

Jan 1, 1980

By R. F. Blakely, P. E. Potter

Any stratigraphic section or bedding sequence can be synthesized if there is a transition procedure from one lithology or bedding type to another, and if thickness distributions of the different lithologies are known. Stratigraphic sections of a fluvial sandstone body were synthesized with five bedding types: cross-bedding, massive beds, parting lineation, ripple mark and mudstone. The transition procedure from one bedding type to another used dependent, Markovian random processes which have a memory that extends one step backward in the depositional process. As observed in nature, median grain size and sand wave thickness (cross-bedding and ripple mark) decline upward in the synthesized sections as proportions of the different bedding types change. Grain size and permeability were also incorporated into the sections. By changing the transition procedures, bed thickness distributions, rate of upward decline or sand wave height and length, different types of sections can be synthesized, thus making it possible to model many different sedimentation problems. INTRODUCTION This paper describes a general method for synthesizing stratigraphic sections and bedding sequences of sedimentary, metamorphic or igneous origin. Synthetic generation is of interest for several reasons. Close correspondence between real and synthetic sections suggests that the factors used in the synthesizing model may indeed be the correct ones, thus giving the investigator a check on his assumptions. Rapid, inexpensive simulation of many stratigraphic sections permits one to synthesize a rock body (sandstone or carbonate reservoir) or, on a larger scale, the fill of a sedimentary basin. Harbaughl gives an example of mathematical simulation of a carbonate basin. He simulated the basin in the hope that improved prediction would follow better understanding of the depositional processes. From the petroleum engineer's viewpoint it seems reasonable to believe that the synthetic generation of rock properties and their distribution in a reservoir should be relevant in the study of reservoirs. Any stratigraphic section or bedding sequence can be generated provided there is a transition procedure from one lithology or bedding type to another, and provided the thickness distributions of the different units are known. The transition procedure involves random processes that are either independent or dependent. If the depositional process is independent, previous deposition will have no influence on present deposition. However, if it is dependent, past deposition will influence either present or future deposition. Such a dependent depositional process can be thought of as having a memory that extends backward in time through one or more pulses of deposition. A process with a memory can be described by a Markov process. Because the concept of memory or dependence appears to be in accord with our understanding of many depositional processes, Markov processes were used to synthesize the bedding sequences of this study (see Appendix). The above methods are perfectly general and are appropriate for any stratigraphic section or bedding sequence: bedding types in a beach deposit, an evolving carbonate bank or the changing lithologic fill of a thick geosyncline sequence. We chose to synthesize a vertical profile of a fluvial sandstone body because its characteristics were well documented, much was known about fluvial processes and fluvial-deltaic sandstone bodies constitute an important class of petroleum reservoirs. CHARACTERISTICS AND ORIGIN OF FLUVIAL CYCLE The fluvial cycle has been well documented in recent years by Bersier,2 Allen3-5and Visher.6,7 Deposits from fluvial cycles range from 10 to 150 ft or more in thickness and are characterized by a "fining upwards": coarse sandstones with occasional conglomerates grade upward into medium- to fine-grained sandstone, and hence into siltstone and mudstone. The dominant sedimentary structure is inclined bedding: thick cross-beds in the lower half

By Ludwig M. Strah

"Wear is a universal problem and is present in all cases wherein one weighted surface moves with or relative to another surface. A practical description of wear as applied to mineral processing plants is outlined.With the advent of higher material and maintenance costs, more attention is being focused on the field of wear resistant linings. The aforementioned is magnified today as the production facilities continue to be designed to handle larger daily capacities. These changes, higher costs and larger plant handling facilities have necessitated the introduction of different materials and designs to combat the never ending battle against wear.In order that wear be understood, it can be relegated to two specific types:1 - Mechanical Wear - due to movement of one loaded surface relative to another.2 - Chemical Wear - more easily defined as corrosionMechanical wearMechanical wear can be subdivided into two basic forms:A.,Material movementB.,Material impactMaterial movement Abrasion is the result of, as earlier stated, the straight move¬ment of one loaded material relative to another.Material impact Is the striking effect when a mass strikes another from various angles and at various speeds. Impact can be severe enough to permanently damage and distort the basic component installed to overcome impact."

Jan 1, 1983

By J. R. Cooper

Since man began beneficiating ores, a limited number of factors influenced the type of treatment. The ore itself has always been a factor. The first form of concentration was probably hand sorting, and the grade of concentrate and recovery had to be considered from the start. The cost of labor as a factor in mill design did not attain importance until the period following World War I. Power was one of the cheapest commodities available, and consequently power consumption was ignored. That no longer holds true. The present work does nothing to simplify the work of the metallurgist, or designer. On the contrary it adds another element to the design considerations. And while this report concentrates on power consumption, the mill designer must take the other factors into account as well. This study is based on a compilation of data supplied by a number of Western United States copper operations, as well as information from equipment manufacturers. Although its conclusiones apply to other minerals and geographic areas, the information is more precise, when applied to similar ores. The discussion has been divided into sections covering crushing, grinding, and flotation as these are the principal power consuming functions.

Jan 1, 1977

By Edward V. D’Invilliers

In connection with some recent professional work in the coalfields of Western Pennsylvania, with special reference to results of coking operations, I was asked to compile a statement giving the estimated cost of mining coal and manufacturing coke at two hypothetical plants of 500 ovens each, giving the relative yield of coal in coke at each plant; and, upon the average number of working days in each of the past five years, from 1899 to 1903, together with average selling price of coke at the ovens, to prepare an estimate of the relative commercial returns in each district. What seemed at first sight to be a comparatively simple proposition, involving only the ordinary elements of mining and coking costs, became complicated by the lack of standard published records of mining costs and sales, which would be applicable to the subject at issue. Upon searching through the usual channels of Government publicatious and the files of our technical societies and mining periodicals, I was surprised to note the absence of fundamental factors that would approximately meet the case in point. The very elaborate and interesting statistics annually published by the National Government' do not supply the required data for the following reasons:—1. Being reported by arbitrary districts, the average values are too general to be applied to special fields. 2. The value of coal charged to the ovens is apparently based upon the regional average value of the coal if sold in the market, and not upon the cost of production. 3. Some plants only use the slack (a by-

Jan 1, 1905

Mining and metallurgical processing of gold and base metal ores often results in solid wastes and effluents containing high concentrations of arsenic. In addition, arsenic can be released to the atmosphere from gold roasters and base metal smelters. Speciation of arsenic in roaster products, in a stack sample from a copper smelter, in organic soils impacted by smelter emissions, and in an anaerobic effluent treatment system at a smelter site was determined in order to broaden our understanding of the nature and occurrence of arsenic in a wider range of metallurgical wastes. Micro-XANES spectra obtained from iron oxide particles forming in a gold roaster indicate preferential enrichment of As3+ species in maghemite-rich domains and microlayers. In comparison, haematite-rich iron oxide particles are dominated by As5+ species. It appears that maghemite is retarding oxidation of arsenic and its volatilisation during roasting. Arsenic occurs as both As3+ and As5+ species in a stack sample emitted from a Cu smelter, confined to fine-grained secondary product layers accumulated on the surfaces of spherical Cu particles. This is probably resulting from condensation of As species upon cooling following their volatilisation during the combustion process. Soil samples collected at various distances from the Cu smelter are dominated by As5+ species including monomethylarsonic acid and tetramethylarsonium iodide as the organic arsenic species. The presence of reduced As3+ species highlights the importance of organic material influencing the speciation of arsenic and mineralogical transformations taking place within the soil profile. The XANES spectra indicate that arsenic occurs predominantly as aqueous arsenite species in the anaerobic treatment system, contrary to the conventional thinking of As retention by the formation of secondary sulfides.

Jan 1, 2008

By Paul Weir

BLEACHING clays have been used extensively in the oil-refining industries for a number of years. Their use in water purification is relatively recent and less extensive. They are frequently classified as (1) those naturally active and (2) those active after artificial activation with acid. Fuller's earths fall within the general group of bleaching clays and gradually the commercial term "fuller's earth" has been applied to natural clays originating, for the most part, in the south- eastern section of the United States. Bentonitic clays are usually classed as activable and are prevalent in the southwestern section of the United States. Bleaching clays vary considerably in chemical and physical properties throughout the country, or even in different parts of one deposit (Table 1). [ ] The fuller's earth type of clay is characterized by a lack of plasticity, relatively adsorbent, foliated structure, and does not swell to form a

Jan 1, 1939

By W. R. Marks

Computer-aided torsional analysis of grinding mill drives is defined and related to the mill design process. Equations of torsional dynamics are developed for general mechanical drives. Consideration is given three solution types - specifically the determination of undamped natural frequencies, the calculation of steady vibration amplitudes, and the prediction of transient torques during starting. Following a summary of the methods of calculating drive motor performance, the problem in making practical application of this theory are discussed. Experiences in both calculating and measuring the torsional loads on a large ball mill with dual synchronous motors are reviewed. Conclusions are drawn on the effectiveness of computer-aided torsional analysis for improving mill drive reliability.

Jan 1, 1984

By W. Yao, M. L. Li, R. Cui

"The purpose of this research is providing a flotation process for recovery of lead in lead silver residues from a zinc smelting plant with a new hydroximic acid collector (HOC). The collecting ability and reaction mechanisms of HOC were investigated based on pure mineral flotation tests and analysis of zeta potential. The pure anglesite flotation tests showed that HOC has a good collecting ability for anglesite. Zeta potential measurements proved that HOC adsorbed on anglesite surface physically and chemically. The lead-silver residues in a zinc smelting plant with lead grade about 17.5% was used as raw material for flotation tests. The results showed that under the conditions of pH adjusting agent lime 500g/t, inhibitors sodium silicate 2000g/t, collector HOC 1500g/t, frother alcohol oil 75g/t, the grade of the lead concentrate can be reach 47.18% and the recovery was 76.39% by one roughing-one scavenging-three cleaning and middles back to the flow-sheet in turn after the lead-silver residues were washed by two stages of cleaning-filtration.INTRODUCTION Nowadays, with the increasing exploitation of natural mineral resources, more and more secondary resources should be researched and used for the valuable metals. Hydrometallurgical zinc leaching residues, which contain a considerable amount of zinc, lead, silver and other minor valuable constituents, is a typical and abundant secondary resources (Zhang et al., 2011). A huge quantity of zinc leaching residues (ZLR) had been produced per year (Jiang et al., 2017).This residues not only occupy precious land but also threaten the environment because of the dissolved heavy metals especially in rainy days (Han et al., 2014). Consequently, it is urgent to develop an effective and clean method to dispose this residues which can benefit not only in economical but also in environmental (Jha et al., 2001)."

Jan 1, 2018

By Robert G. Paul

President Reagan's Exclusive Economic Zone (EEZ) Proclamation of March 10, 1983, extended United States ocean jurisdiction 200 nautical miles offshore our coastal states and territories. The accompanying policy statement noted that this action was a result of recently discovered deposits of polymetallic sulfides and cobalt-rich manganese crusts, which could be a major source of minerals important to the U.S. economy and security. Within these 3 billion acres of exclusive economic jurisdiction, the United States has sovereign rights to explore, develop, conserve, and manage the mineral and other natural resources of the seabed. The President has directed the Department of the Interior (DOI) to encourage exploration and production of minerals from this area. The DOI, through the Minerals Managment Service (MMS), is responding to this presidential directive by developing a leasing program for nonenergy minerals in the EEZ. The authority to develop this leasing program is the Outer Continental Shelf Lands Act of 1953, as amended in 1978, which authorizes the Secretary of the Interior to grant leases for oil, gas, sulfur, and other mineral resources on the Outer Continental Shelf (OCS). The Solicitor of D01 has determined that the definition of the OCS for legal purposes extends at least 200 nautical miles offshore of our coastal states to the EEZ boundary. Section 8 (k) of the Act allows the Secretary to lease minerals, other than oil, gas, and sulfur, on the basis of competitive bonus bidding and under such terms and conditions as he may prescribe at the time of offering the area for lease.

Jan 1, 1985

By A. Raraz

The optimization of the plutonium electrorefining process has been studied on the basis of modeling and model materials. The plutonium electrorefining process has been reviewed and the basics of the electrorefining process with molten salts as electrolytes and under forced convection has been presented. The definition of the problem in plutonium electrorefining has been related to three factors and this research has addressed these three factors to provide an insight to this process. The hydrodynamic factor gives information on the behavior of the mechanically stirred system. The chemical stability and solidification factor shows the interactions among the components of the electrorefining cell. The electrochemical factor is oriented to study the efficiency of the electrorefining process on the basis of limiting current density, stirring rate and configuration cell. As a result of this study the optimization of plutonium electrorefining implies mainly a re-design of the cell.

Jan 1, 1995

By W. K. Connor, O&apos

The U.S. Bureau of Mines investigated the Sheep Creek prospect in the north-central Alaska Range to evaluate the Pb, Zn, Ag, and Sn resources. The studies included field investigations, mineralogical characterization, and concentration tests. Mineralization at Sheep Creek consists of disseminated, banded, and massive pyrite, sphalerite, and galena. Tin occurs as grains of cassiterite (Sn02) in the quartz-mica matrix and within pyrite and sphalerite grains, and Ag occurs in solid solution within the galena. Three bulk surface samples and two sets of core samples were collected at the Sheep Creek prospect for this study. Gravity concentration yielded products with up to 30 pct Sn, and the best result was a product that recovered 52 pct of the Sn at a grade of 22 pct Sn. Bulk sulfide flotation yielded products that recovered up to 89 pct of the Zn, 73 pct of the Pb, and 75 pct of the Ag, but grades were relatively low; selective flotation would significantly increase the grades.

Jan 1, 1989