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By James S. Graham

Research at the University of Colorado on southern pine and Douglas-fir piling has determined that the existing building code design stress values of 1200 psi and 1250 psi, as determined by ASTM D-2899, are substantiated; but testing procedures should be revised. All full size piling tests should be standardized at 1/d ratios of 2:1, or confined tests performed. Also, it has been determined that theoretical design values for timber piling should not be based on the lumber criteria of D-245 and D-2555, but instead should follow the pattern set by engineers in the utility industry for timber poles, in accordance with ANSI 05.1.

Jan 1, 1986

By F. T. Principe

In order for solvent extraction technology to be acceptable as an alternative to existing jarosite precipitation circuits, iron must be cleanly separated and concentrated into a feed stream suitable for downstream iron by-product recovery which meets market specifications and economics. Ten years ago, significant progress was made in a joint McCill University/CANMET project that involved iron extraction with mono(2-ethylhexyl) phosphoric acid and stripping with HCI. Our iron solvent extraction research was reactivated recently by looking into this and other members of the organophosphorus extractant family. Our research focuses on the mechanisms and control of anion (SO42/CI) transport across the various phases (Rafinate/Organic/Strip), iron build-up in the strip liquor, and extractant stability/selectivity. In this paper, these issues along with some other performance parameters are discussed using data derived from an extensive search of the two commercially available and best known members of the organophosphorus family, di-2-ethylhexyl (D2EHPA) and mono-2-ethylhexyl (M2EHPA) phosphoric acid. Further in this discussion, the challenges lying ahead in the development of sx systems that overcome the deficiencies of D2EHPA and M2EHPA are outlined. In particular, the necessity of considering secondary separation technologies that can further concentrate iron values in the chloride strip liquor to levels economically attractive for the production of saleable iron oxide by pyrohydrolysis is addressed.

Jan 1, 1998

By N. H. Emmons

(Canal Zone Meeting, November, 1910.) AN interesting development of copper blast-furnace construction has been brought about in adapting the blast-furnace to be a "burner" for sulphuric acid making. When the Tennessee Copper Co. first decided to construct an acid-plant, the standard type of brick-top furnace, supported by structural steel, was the only one in use at this plant. All the tests for temperature and strength of gas had been made on these furnaces, and had been satisfactory. When, however, the acid-plant was put on the flue, and the flue had to have a damper put in it to force the gas into that plant, troubles began. The furnaces were fairly tight, and for a few months the work was quite satisfactory., Fig. 1 shows the old type of furnace-top used at the start. It was soon found that this top would not stand the temperatures, particularly when dampered back, as was necessary to force the gas into the Glover towers. The structural steel, of which the furnace skeleton was constructed, warped and twisted so badly that it was not safe to use the furnaces. This effect is shown by Fig. 2, which is a photograph of old No. 4 furnace, after the brick-work had been removed. It became apparent that a new type of top was necessary and the engineering force was started oil the design of a new furnace-top, with the result that a low top, with brick-lined flues at each end below the feed-floor, leading to the main concrete dust-chamber, was constructed. This furnace, No. 7, is shown in Fig. 3. The charging-doors are made of cast-iron sections, three sections to a door, and three doors to a side. A door to the furnace was made of cast copper, but the heat was so great that the copper bent readily, due to the jarring of its * General Manager, Tennessee Copper Co.

Feb 1, 1911

By M. F. Goudge

MAGNESIA refractories and magnesium metal are both essential war commodities. The need for magnesium, which had just made its debut as a commercial metal a few years before the outbreak of the present war, is widely known because this new and valuable light metal has already received much publicity. Less widely known but equally important in the war effort are magnesia refractories. They are indispensable to the efficient functioning of the great metallurgical plants producing steel, nickel, copper, and other metals, where, because of their resistance to extreme high temperature and chemical attack, they are used in lining the furnaces, which are operated at a white heat. The demand for refractories in the metallurgical industries rose rapidly upon the outbreak of war, and now, in consequence of the continued great expansion under way in the manufacture of steel, nickel, copper, and other metals, the need for magnesia is greater than ever. Since 1915, part of the Canadian requirements of basic refractories has been supplied from the deposits of magnesitic dolomite in Argenteuil county, Quebec. The products from these deposits are excellent for many uses, but the magnesitic dolomite has too high a content of silica and lime to be used in making a type of magnesia brick required in nickel converters, and in the roofs of reverberatory furnaces used in the copper and steel industries. There is now a large and growing demand in Canada for bricks and shapes for these uses. This demand has always been supplied from the United States. Makers of these products in the United States, in turn, formerly imported most of the necessary high-grade, dead-burned magnesia from Austria and Manchuria. Not only are these sources closed, but refractory chrome ore from the Philippines is no longer available and chrome refractories may have to be in large part replaced by magnesia.

Jan 1, 1942

By A. J. Forney

Recent experiments used catalysts of plate assemblies in synthesizing high-Btu gas and gasoline indirectly from coal. A gas with a heating value of 925 to 943 Bt-: per cubic foot has been prod u la the hot-gas-recycle pilot plant from synthesis gas (3H2+100) with lathe turnings used as catalyst in the first reactor, and assemblies of parallel sprayed plats of nickel in the second. Solid plates made of Raney nickel, and steel and aluminum plates sprayed with Raney nickel or nickel oxide were tested. Those catalysts had very low resistance to gas flow; 90 percent lower than nickel granules used in previous experiments. In a single stage of synthesis thee nickel plates were only partially successful. Although the heating values of the product gas ranged from 856 to 941 Btu per cubic foot, the carbon monoxide content of he gas was above 0.1 percent. Both steel and wrought turnings were tested in single-stage synthesis, but the conversion of hydrogen and carbon monoxide was too low to attain the desired heating value of 900 Btu per cubic foot in the product gas. Assemblies of plates thermally sprayed with fusel iron were tried in an experiment to make gasoline. A gasoline yield of 52 percent (of the hydro¬carbons produced) was obtained using a 1H2-10O feed These sprayed assemblies were in service for 1,500 hours, the longest that this type of catalyst has been used. When a second reactor containing Raney nickel catalyst was added in series with the first reactor, complete utilization of the feed gas was obtained because in addition to the liquid product, a high-Btu gas with a heating value of 800 Btu per cubic foot was made.

Jan 1, 1965

Presentation Overview Corporate Overview Kutcho Project History Exploration Development Permitting Capstone -Pursuit of Value Building a mid-tier copper producer focused in the Americas Two operating copper mines; Cozamin& Mintomines High grade and low cost 2010 forecast: 80-85 million pounds of copper in concentrates Total Cash Costs* of ~US$1.10/lb to US$1.20/lb of payable copper produced Significant by-products of gold, silver, lead & zinc Growth potential Further expansions at existing Cozamin& Mintomines High grade copper development: Kutcho project, BC Investments in Nevada Copper & Silver Wheaton 100% North American assets Low risk ?Canada & Mexico ?Conventional operations

Oct 1, 2010

By W. Petruk

An investigation was conducted to determine the minimum number of samples that must be studied by image analysis of polished sections in order to characterize a mill product and to determine the apparent mineral liberation. It was found that a representive polished section cannot be prepared from an unscreened sample that has a wide size range of particles. Similarly individual screened' fractions are not representative of the sample because minerals are partitioned during screening. Consequently the quantities of soft brittle minerals are increased in fine grained fractions and quantities of hard minerals are increased in coarse grained fractions. It is assumed that results obtained by combining data for a series of narrow size range screened fractions (1 Tyler size range) are representative of the sample, and relatively accurate apparent mineral liberation data can be obtained for a mill product by analysing each fraction and combining the data. Somewhat less accurate data would be obtained by analysing a series of screened, fractions that have a wider size range of particles (5 Tyler size ranges). Mineral liberation analyses show that the most reliable apparent mineral liberation in each screened fraction is a value taken from a smooth curve drawn through the lowest points on a graph of % free vs size. A correlation between the apparent mineral liberation in screened fractions and calculated mineral liberations using Kings liberation model is good for sphalerite but not for chalcopyrite and galena.

Jan 1, 1985

By Pekka Hanniala

The Outokumpu Flash Smelting process today is the most feasible method for copper matte smelting. The economic feasibility of the process has always been one of the main decision making criteria in smelter projects. Thus, today about 50 % of the world primary copper production utilizes Outokumpu Flash Smelting Technology. However, in the future, environmental criteria will have stronger and stronger impact on decision making. Flash Smelting technology offers the best pollution control features of any process. today. It is foreseen that, in the near future, the global trend will be that all the smelters must decrease their emissions at an accelerating rate, compelling the smelters to make increasingly larger investments on environmental protection. In most of smelters ?today, Peirce-Smith converting and transfer of the molten material in ladles are the number one pollution source. The key today for copper converting and minimizing emissions is the Kennecott-Outokumpu Flash Converting process, which has proven to be the most effective converting method in terms of pollution control and, production efficiency including capital and operational costs. Outokumpu Flash Smelting technology is applicable also for small to medium scale smelters but the most interesting area is the upper capacity limit for smelting in one line, which has not yet been reached. We predict that by the year 2000 to 2005, there will be at least one smelter which produces 500,000 tonnes of Cu per year based on one Flash Smelting and Flash. Converting unit. The current state-of-the-art of the Outokumpu Flash Smelting - Flash Converting process is presented in this paper as well as some new options for copper production to be utilized in the near future but which are available already today.

Jan 1, 1998

By S. Uihteenmaki

Pyhasalmi is a massive sulfide orebody located in central Finland. The mine has been in operation since 1962. The flotation concentrator produces Cu, Zn, Pb and pyrite concentrates. The plant has used an on-stream analyzer for process control since 1968. The original analyzer has overlived a few generations of minicomputers, but the analytical parts are essentially unchanged. The on-stream analyzer is a critical component in plant process control system, which has made Pyhasaltni one of the pioneers in the art of computer control and optimization of flotation plants. The paper summarizes the experiences gained from the use of the high performance elemental analyzer system and the proven benefits from the use of on-stream analyzers at a complex sulfide flotation. The aging analyzer is approaching the end of its useful life. A new state of the art analyzer system is undergoing testing at Pyhasalmi.

Jan 1, 1999

By Noel A. Warner

Modern steelmaking is based on direct use of oxygen in high intensity batch reactors. A totally new approach is proposed in this paper, based on the view that pursuit of high intensity is unlikely to lead to successful coal-based continuous steelmaking. By substituting carbon dioxide and water vapor as the oxidants rather than using oxygen directly, the intensity is greatly reduced. Accordingly, subsurface formation of carbon monoxide bubbles can be avoided by careful manipulation of the three participating rate processes, gaseous diffusion, interfacial chemical kinetics and liquid phase mass transfer. Steelmaking can then be carried out without explosive ejection of molten droplets and the generation of micro-spray but rather in a controlled and fume less fashion. The vital component is the introduction of generic melt circulation technology. Three melt circulation loops in series are envisaged. Starting with a composite feed of iron ore fines, pulverized coal and lime flux, a metallized solid raft floating on molten iron is propelled out of the ironmaking loop onto the first of two downstream steelmaking loops. In the first, a liquid slag is formed, primary decarburization is undertaken not with oxygen but rather with CO2 and H2O and the melt is desulfurized. The semi-product stream enters the third melt circulation loop, where open-channel decarburization is effected along with dephosphorization to yield a low carbon steel product. Alternatively, the melt leaves the last loop to irrigate a packed tower countercurrent to argon at around 100 mbar to continuously produce ultra-low carbon (ULC) steel.

Jan 1, 2003

By Nikhil Dhawan, Sanjay Pindar

The limited lifespan, ever-growing demand, and significant lithium and cobalt content are responsible factors for the immediate recycling of discarded lithium-ion batteries. Discharged batteries were dismantled, segregated, and size reduced to recover cathode and anode material. The active cathode material comprises LiCoO2 (65.8%) and LiMn2O4 (34.2%) and was carbothermal reduced with recovered graphite in a microwave furnace followed by water leaching and magnetic separation. A Box Behnken statistical experimental design is used for process optimization. Both cobalt and manganese report to magnetic fraction, whereas graphite and lithium carbonate report to non-magnetic fraction and solution crystal respectively. The final product comprises of cobalt 73% and manganese of 14% with process yield of 36% and saturation magnetization of 76 emu/g.

May 16, 2020

By Louis W. Huber

The Liberty tunnels extend through a very steep hill in Pittsburgh (locally called Mount Washington) for a distance of slightly over a mile. The two tunnels parallel each other and are 59 ft. apart, center to center (Fig. 1) They are for vehicular traffic, and in each there is ample space for two lines of vehicles. Northbound traffic, toward downtown Pitts- burgh, is confined to the east tunnel and southbound traffic to the west tunnel. The South Hills residential district is separated from downtown Pittsburgh by Mount Washington, a steeply rising escarpment south of and adjacent to the Monongahela River. The Mount Washington district immediately south of the Monongahela River has been reached, for many

Jan 1, 1927

By R. E. Morgan

[IN COMPILING the table of analyses of this bulletin every available source of information was studied. These sources, as listed at the end of the table, were many and varied, and it believed that the tabulation gives the best general information obtainable. However, its known accuracy and completeness of coverage necessarily fall far short of published data on coals of the United States. A table of world production of coal and lignite, as and published by the Bureau of Mine, of world resources of coals, brown coal, and lignite, as published in the Yearbook of the World Power Conference, 1948, are included for convenience of the reader. The six continental maps at the end of the bulletin show the general location of the principal coal fields.]

Jan 1, 1952

By J. R. Dyni

The lacustrine Green River Formation of Eocene age in the Green River Basin, southwest Wyoming, contains the world's large resource of natural sodium carbonate in bedded trona (Na2CO3? NaHCO3? 2H2O). In this study, 126 billion tons are estimated to be present in 22 beds, ranging from 4 to 36 feet in thickness. These 22 beds underlie areas of about 50 to more than 775 square miles at depths ranging from about 650 to more than 3,000 feet below the surface. The total resource of trona ore in the basin for which drilling information is available is estimated to be about 149 billion short tons. The undeveloped deeper trona beds in the southern part of the basin may be exploitable by solution mining. Additional unevaluated sodium carbonate resources are present in disseminated shortite in strata interbedded with the trona and in shallow sodium carbonate brines in the northeast part of the basin.

Jan 1, 1995

By Wing G. Agnew

The first six Reports of Investigations in this series , pertaining to the investigation of stemming at the Mount Weather Testing Adit, dealt with ( 1 ) the dust produced by blasting , ( 2) the effect of stemming upon gases generated by blasting , ( 3 ) the relative advantages and disadvantages of different types of stemming and no stemming when used with 60 - percent ammonia gelatin dynamite , (4) the length of stemming material through which a primer will fire and detonate a charge of dynamite , ( 5) comparison of dust and gases produced when blasting charges of dynamite in drill holes , bombs, and mud - cap shots , and ( 6 ) the relative advantages and disadvantages of different types of stemming and no stemming when used with 40 - percent ammonia gelatin dynamite .

Oct 1, 1943

By Weller KR

A study of high pressure rolls grinding of a number of Australian ores and minerals has been carried out using a pilot-scale machine with rolls 300 mm diameter and 70 mm wide. The results from this study have been used in conjunction with plant survey data to construct computer simulation models of various comminution circuits and these have been used to investigate options for incorporating high pressure grinding rolls into these comminution circuits. Possible rolls options for three of these circuits are presented, and likely energy savings over the existing circuits are discussed together with potential improvements in plant throughput and/or product sizing. A scale-up procedure for predicting full-scale machine performance from small-scale testing is described, and the effects of rolls operating conditions are also discussed.

Jan 1, 1991

By Xiaochao Shu, Kun Wang, Fanwei Meng, Rui Tao

Rapidly searching for carbonatite-related rare earth element (REE) mineralized systems is of paramount importance to explorers, because these systems provide the world’s most significant supply of REE. Biotite and barite are suitable indicator minerals that can offer reliable elemental geochemical information used for REE exploration. In this study, we provided an elemental geochemical dataset of biotite and barite from Cenozoic REE deposits in the eastern Tibetan Plateau, and compared the obtained data to those of biotite and barite forming in other geological settings. The F (i.e., fluorine) contents in carbonatite-hosted biotites are highly variable, with biotites from mineralized carbonatite complexes having much higher values (1.05–2.37 apfu, where apfu = atoms per formula unit) than their counterparts from barren carbonatite complexes (≤ 1 apfu). It is therefore believed that the presence of high-F biotites can be regarded as a sign for predicting REE reservoirs. Barites in REE mineralized systems contain much higher (even one or to orders of magnitude) total REE contents (ΣREE >100 μg/g) relative to those species forming in carbonate-hosted fluorite-barite deposits and open marine environments. This means that the high ΣREE concentration of barite can serve as an effective index for REE exploration. The above information is integrated into a REE exploration program in which the areas with strong local tectonism along cratonic edges are priority exploration targets, and high-F biotites and REE-rich barites can serve as direct indices for rapidly identifying carbonatiterelated REE mineralized systems at a strategic distance from other geological settings.

Jun 9, 2023

By Gordon E. Forward

Sustainable development in the mining and metallurgical industrial sectors can be implemented by two distinct groups: 1. The managers and operators of existing facilities ? working with industrial processes and systems that have been operating for many years, in some cases several decades 2. Those who are engineering and building new facilities or upgrades of existing plants. The focus of this paper is to look at approaches and tools available to bring sustainable development thinking and action to these two distinct areas. The paper will discuss: 1. The concept of working with existing facilities and processes to minimize waste and maximize product from a regional raw material/resource consumption perspective using By-product Synergy. The BPS concept has been carried out in Texas (TXI-Chaparral?s STAR Example), in Calgary, Alberta with Suncor assistance, in Montreal, Quebec with Noranda as project leader and currently in Ontario with Dofasco as industry champion. Successful outcomes are presented. 2. A new approach to designing greenfield facilities or upgrades to existing plants using a sustainable development review process. Undertaking the review early in every project can institutionalize the concept of discussing and implementing waste elimination, design for environment, eco-efficiency, risk minimization and community awareness and involvement in the future capital stock. The review process has been developed as an excellent tool for measuring and reporting on a corporation?s sustainable development progress. Examples of how this approach has been adopted in the mining and metallurgical industry, and the resultant outcomes are given.

May 1, 2002

By S. W. Miller

MOST of the steel welding done at the present time is in material containing not over 0.3 per cent. carbon, and the tests here described were in similar material. These tests are not as yet completed but it is hoped that more results and more reasons for the conclusions may be presented at the meeting in February. From the time the author found the peculiar structure in electric welds referred to in a previous paper,1 that is, needles or plates in the grains and similar material, in larger spots, at the grain boundaries, he has felt that these plates which may be iron nitride and probably contain some carbon, were at least partly responsible for the brittleness of electric welds. He has found but few traces of similar lines in oxyacetylene welds until the last 2 mo., when he has found them in large numbers under certain conditions. In the top of these welds, they are quite numerous. In the body of heavy oxyacetylene welds, they appear at times, but not nearly to the extent that they do in electric welds; the author has never seen them in the body of welds in material less than ;3/4 in. (19 mm.) thick. They are shown in Fig. 82. The reason they were not noticed before is undoubtedly due to the fact that in making tests of welded pieces the weld was always ground off level with the plate, and as this structure only appears in the top ;1/16 in. (1.5 mm.) of the weld, they were removed by the grinding or machining; also, welds ¾ in. thick had not been examined. It did not appear, in making bending tests, that this structure had much influence on the strength of oxyacetylene welds; while electric welds are noticeably brittle. Further, oxyacetylene welds made with certain special materials were exceedingly brittle even after the tops of the welds were removed; this was true in cases where there was no sign of the plates whatever and where the welds were remarkably free from oxide and the other usual defects. It appeared, therefore, that this brittleness did not depend on any variable that had been noticed so far, and it was

Jan 2, 1919

By S. W. Miller

MOST of the steel welding done at the present time is in material containing not over 0.3 per cent. carbon, and the tests here described were in similar material. These tests are not as yet completed but it is hoped that more results and more reasons for the conclusions may be presented at the meeting in February. From the time the author found the peculiar structure in electric welds referred to in a previous paper,1 that is, needles or plates in the grains and similar material, in larger spots, at the grain boundaries, he has felt that these plates which may be iron nitride and probably contain some carbon, were at least partly responsible for the brittleness of electric welds. He has found but few traces of similar lines in oxyacetylene welds until the last 2 mo., when he has found them in large numbers under certain conditions. In the top of these welds, they are quite numerous. In the body of heavy oxyacetylene welds, they appear at times, but not nearly to the extent that they do in electric welds; the author has never seen them in the body of welds in material less than ;3/4 in. (19 mm.) thick. They are shown in Fig. 82. The reason they were not noticed before is undoubtedly due to the fact that in making tests of welded pieces the weld was always ground off level with the plate, and as this structure only appears in the top ;1/16 in. (1.5 mm.) of the weld, they were removed by the grinding or machining; also, welds ¾ in. thick had not been examined. It did not appear, in making bending tests, that this structure had much influence on the strength of oxyacetylene welds; while electric welds are noticeably brittle. Further, oxyacetylene welds made with certain special materials were exceedingly brittle even after the tops of the welds were removed; this was true in cases where there was no sign -of the plates whatever and where the welds were remarkably free from oxide and the other usual defects. It appeared, therefore, that this brittleness did not depend on any variable that had been noticed so far, and it was

Jan 2, 1919