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By C. Caballero, A. Warczok, K. Itagaki, A. Moyano, J. Font

The Codelco Norte Smelter process 2,500 tpd of arsenic-bearing concentrates with an arsenic content of up to 1.5% in one of its two main smelting units, the Teniente Converter. The product, 1,100 tpd high-grade matte or white metal, is traditionally fed to the PS converters, while the 1,700 tpd of slag is fed to the slag cleaning electric furnace for copper recovery. This is achieved in a very reductive environment which reduces the viscosity of the slag and enhances the sedimentation of the high-grade matte droplets. The behavior of arsenic in this non-oxidative environment was studied at lab-scale and fundamental thermodynamic data were obtained. Based on these data a thermodynamicbase model to assess the arsenic behavior in reductive environment was developed. It is based on a mass balance for the reduction and sedimentation stages performed in an electric furnace which allows the recovery of high-grade matte droplets after decreasing the viscosity of the slag. This model can be a very suitable tool for predicting fractional distribution of arsenic in the slag cleaning electric furnace, when the distribution ratio, vapor saturation degree, temperature, y As and pO2 are given.

Jan 1, 2007

By K. Blower

"Since there was no representative from Wesfrob Mines Limited, the information on their infra-red concentrate drying operation, which had been prepared by Mr. K. Blower, was presented by Mr, Dorland. Mr. Blower, in submitting the information, emphasized that their objectives in this operation were (a) to guarantee less than 90%, of flow-moisture in their copper concentrates and thus satisfy marine shipping regulation• and (b) to minimize capital costs, The infra-red dryers have satisfied these objectives.To control final moisture in the copper concentrate, current practice is to preheat the filter cake with steam in the disc filter hood and then conveyor-0r7 the concentrate with infra-red calrod heaters. The application of steam aids the system as follows:1) Improves vacuum pump efficiency.2) Lowers viscosity of filtrate (increased temperature},3) Preheats the cake prior to radiant heating. (150°F)The hot cake discharging from the filter ranges from 10.6 to 10.9% moisture. After radiant heating the moisture level is reduced to 8.5% - 9.7% depending on production rate. Further moisture loss occurs during conveying and transferring to the stockpile for a final shipment moisture ranging from 8.1% to 9.5%. Production rate is frail J to 5 dry short tons per hour.1) #23 Conveyor 18"" flat belt covered from filter discharge to transfer point with 7 heaters end-to-end. Drive - Reeves Vari-Speed, 31:4 ratio, type 332-10-18, class ""D"", driving through a 24:1 ratio Dodge reducer. Speed of Conveyor - 3,9 feet per minute to 19.6 feet per minute. (Speed has been established and is not changed as a rule from the present level of a1:out 15.)2) #23 Conveyor 24"" wide, 20° troughed belt covered with 21 heaters, end-to-end from loading point, Speed - Constant at 54,2 feet per minute."

Jan 1, 1972

By Richard C. Williams, Herman Pieterse, Ken Thomas, K. S. Fraser, Ron H. Colquhoun

"The Banick Goldstrike Mines Inc. (Goldstrike) operation is located in Eureka County in north-central Nevada on the Carlin geological trend. Gold in the sulphide mill feed, occurs primarily as submicroscopic inclusions or possibly solid solution in a pyrite and marcasite matrix. Sulphide mill feed is pretreated in a pressure oxidation plant allowing gold recoveries of 90 per cent and greater to be achieved. Anticipated 1994 gold production for the sulphide gold facility is approximately 1,500,000 ounces.In January 1989 American Banick Resources Corporation (Banick) announced the US$365 million Betze Development Plan for the Goldstrike property. The Betze plan was based on a three (3) staged expansion of the original 4,500 STPD oxide gold plant. This expansion would involve addition of ore and gold processing capacity and the total conversion of all ore handling facilities to treating Betze sulphide ores.Phase 1 of the Betze Development Plan involved the construction of a pressure oxidation circuit, including a single autoclave and supporting ancillary services. The pressure oxidation circuit was commissioned in February 1990. Currently a throughput of 2,000 STPD is being achieved.Phase II of the Betze Development Plan, commissioned throughout April and May 1992, included the expansion of grinding, leaching, and gold recovery facilities enabling the treatment of combined oxide, and sulphide ore. Pressure oxidation capacity was increased by the addition of two (2) autoclave circuits each treating 2,600 STPD of sulphide ore and other required ancillary services. By June 1992, the Phase II gold facility had achieved a combined throughput of 15,000 STPD of oxide and sulphide ore.Phase Ill, the final stage of the Betze Development Plan, was successfully commissioned in February and March 1993. This final stage of development increased the design throughput of the pressure oxidation plant to 15,000 STPD by the addition of three (3) autoclave circuits with combined capacity of 7,800 STPD."

Jan 1, 1994

By J. F. Wang, Y. Jin, Z. L. Wang

Smelting reduction as an ironmaking technology for the 21st century has been challenging the traditional blast furnace. The process has many attractive advantages over the blast furnace, however, the massive by-produced coal gas mainly containing CO, H2 and CO2 requires further treatment. From a chemical engineering view, coal gas is a valuable chemical stock and can be transformed into hydrogen-rich synthesis gas. Hydrogen can be directly used as clean fuel and synthesis gas can be used for the production of some important chemicals such as methanol, ammonia and dimethyl ether. Among those chemicals, dimethyl ether as an alternative clean fuel for diesel engine and liquefied petroleum gas has been drawing more attention. It has excellent environmentally-benign behaviours not only in compression ignition combustion, but also in the much lower emission of SOx and NOx. In this work, a combined technology of smelt reduction ironmaking and direct synthesis of dimethyl ether, which will strongly promote the energy efficiency, environmental protection and resource recovery, is proposed and described in detail.

Jan 1, 2004

By W. Zieman

"The low consumption of reagents can probably be attributed to a good clean type of ore. The cyanide level is kept at 0. 8 lb/ ton of solution and the lime at 1. 8 to 1.9 lb per ton of solution (pH 12. 2 to 12 .3). Experience in cutting down the lime level in half produced troubles in the presses, in the refinery and resulted in higher cyanide consumption. Finally the residue increased under these conditions, High lime always seems to prevent the trouble from occurring.A survey at one mine of the taxable work, performed in the mine shops for use in the mine, showed that under the new regulations, this had increased some 30 times what it was before the new rules came into effect on June 14, 1963.A water softener idea is incorporated at Lamaque with the crude addition of 100 lb of lime per shift to a spare agitator to precipitate the bicarbonates as carbonates from the water before it enters the mill. The lime titration of the softened water is about 0,2 to 0.3 lb per ton of solution (pH 11). This water is used mainly on the filters as washes."

Jan 1, 1964

By M. Labrie, H. L. Gibson, G. Doiron, J. J. Watkins, D. H. Watkinson

The Corbet deposit is one of 17 proximal Cu-Zn massive sulfide deposits located. within the Noranda Cauldron which occurs within the core of the Noranda Volcanic Complex. The deposit is located at the top of the Havrian Formation, the lowermost formation of the 3000 m thick Mine Sequence; the deposit has Yielded 2.75 M tonnes of ore grading 3% Cu, 0.96% Zn, 2.06 g/t Ag and 1.0 g/t Au. The multi-lens Corbet deposit formed within a 250 m wide crater that occurs within a localized breccia pile. The Corbet breccia pile was constructed by explosive magmatic and hydrovolcanic eruptions localized along the south flank of a larger andesitic shield volcano that formed during the waning stages of Havrian volcanism. The breccia footwall of the deposit allowed unfocused and widespread hydrothermal discharge that resulted in the development of a large area of chlorite and fringing sericite alteration that exceeds, by six times, the size of the sulfide lenses and represents a significant exploration target.

Jan 1, 1993

By Barry D. Simmons

Abstract -A well-defined approach is essential to ensure the long-term success of a regional exploration program. Teck's approach in eastern Canada is designed to fulfill corporate objectives while recognizing certain unique parameters for exploration in the area. The elements of this approach include clearly defined objectives, technical considerations and personnel policies, all of which are equally important. The goal is a significant discovery before the mid-1990s and the company is confident that this target will be achieved.

Jan 1, 1992

By Y. Obara, A. Sato

"Limestone is one of the most important mineral resources, and in Japan it is only one mineral which can be fully supplied by the domestic product. Generally limestone mines in Japan located at mountainous regions, and the combination between bench-cut method and the carry-out system using vertical shaft is widely used in the domestic mines. During mining operations, the occurrence of the blockage in the vertical shafts is very serious problem. Once the blockage in the shafts is occurred, a lot of works and dangerous procedures are necessary to solve the problems. It is thought that blockage is influenced by the cohesion and friction coefficient due to clay minerals thrown into the vertical shafts, however, the quantitative and precise reason is not revealed yet.In this study, the process of blockage occurrence was simulated by 2-Dimensional Discrete Element Method (DEM). In the 2D-DEM analysis, discontinuous circular particles are generated, and the individual movement of each particle is calculated by forward difference method. In the analysis, several typical ore distributions are applied, and the DEM analysis was conducted under the various combinations of cohesion and friction coefficient. From analytical results, it was found that the friction coefficient strongly influences to the occurrence of blockage and there were a threshold values which blockage does not occur. Several kinds of shaft shape were also simulated towards different ore size distributions, and those influences to the blockage occurrence were also discussed."

Jan 1, 2015

By Jeremy D. Glennon

A number of exciting challenges, opportunities and unanswered questions remain concerning the chemistry, geochemistry, medical, industrial and analytical applications of gold and its compounds.1 Among the challenges presented is the need for extraction methods for gold, at process and indeed analytical scales, that avoid the use of organic solvents or hazardous reagents. Extensive environmental contamination has occurred in the Brazilian Amazon from the mercury-gold amalgamation process. Major problems with the cyanidation process are the relatively slow dissolution kinetics and the health and environmental problems associated with it. With innovation and technical changes, a cleaner way for solubilising and extracting this versatile precious metal can be found. This cleaner future may lie in supercritical fluid science. Interestingly, geochemical studies of gold solubility and speciation in hydrothermal solutions have highlighted the importance of supercritical conditions and sulphur species in the deposition of gold in natural environments. Gold solubility in supercritical brines is far higher than previously supposed while interest in the high content of carbon dioxide in the mineralizing fluids is growing. 2,3 In recent years, also, there has been a tremendous amount of attention paid in analytical chemistry and in industry, to the area of supercritical fluid extraction (SFE) of organic and metallic species. 4 This interest has been fuelled by the introduction of more stringent environmental control and the subsequent need for cleaner solvents and processes to replace established ones. Carbon dioxide is the substance of choice for SFE because of its moderate critical parameters (Tc = 31oC, Pc = 73atm), inertness and availability in pure form. It is an excellent extraction medium for non-polar and moderately polar species, and with careful ligand design, it can be used for analytical and process scale metal extraction from solution and solid phases. In general, the dissolution of a metal in supercritical CO2 (sc-CO2) requires that the charge on the metal ion be neutralised on complexation by the ligand or through a form of ion pairing (analogous to the situation where metal ions are extracted into organic solvents, such as methyl isobutyl ketone or toluene). In this way, then, many chelating agents such as dithiocarbamates and hydroxamic acids have been utilised to extract metal ions such as Cu and Fe into sc- CO2, the process greatly enhanced by the use of fluorinated ligand derivatives. 5-7 In this review paper, we show that supercritical conditions and complexation with sulphur donor atoms, important in the natural deposition of gold, can form the basis of a clean, eco-friendly chemistry for gold extraction. Analytical scale extractions of gold from a variety of matrices can be conveniently used to assess the efficiency of any new proposed ligand.

Oct 1, 2003

By R. V. Hopper, M. E. Wilson, L. S. Trenholme

"The Company known as Rouyn Merger Mines, Limited, was formed in 1943 to take over the ownership of claims in Rouyn and Joannes townships formerly held by East Rouyn Mines, Limited, O'Neil Thompson Mines, Limited, and the Hosking-Cockeram Prospecting Syndicate. The NorandaSenneterre branch of the Canadian National railway passes in an approximately east-west direction through almost the entire length of the property. Since 1937, sixty-three diamond drill holes have been drilled from the surface to cross faults on the contact of the Timiskaming sediments with the Abitibi ( Keewatin) volcanics, along which ore has been found to occur. Late in 1945, the sinking of a 3-compartment inclined shaft in the andesite agglomerate beneath the ore zone was commenced. On January 17th, 1947, this shaft had a depth of 944 feet; cross-cuts have been driven north-northwest from the shaft at 150-foot intervals from depths of 200 to 800 feet on the shaft (Fig. 2).GEOLOGYThe western or East Rouyn part of the Rouyn Merger property in which ore is being mined adjoins the area owned by McWatters Gold Mines, Limited, on the east and is underlain by the eastern continuation of the McWatters formations. As at the McWatters, the rocks belong structurally to three areas: (1) the territory north of the Cadillac-Bouzan Lake fault, occupied almost wholly by Abitibi ( Keewatin) volcanics; (2) the area along the south boundary of the property, underlain by Timiskaming conglomerate and greywacke; and (3) the synclinal belt of McWatters volcanics and sediments between areas 1 and 2.1Bouzan fault of Hawley."

Jan 1, 1954

By C. R. Hocott

"IntroductionRESEARCH in petroleum production consists primarily in investigations related to the drilling for and recovery of oil. As an organized activity of individual oil companies, production research is now 30 to 35 years old, and the petroleum industry may point with justifiable pride to the achievements of this third of a •century. Emphasis on research has grown through the years until at the present time many of the larger companies operating in the United States •have well-organized production research staffs.In addition to the efforts of the oil companies, significant research and development in petroleum production technology have been performed by oilfield service companies and others. Valuable contributions have been made through fundamental research carried on by the U. S. Bureau of Mines and by various colleges and universities, both in their own programmes and in programmes sponsored by industry, such as those of the American Petroleum Institute. However, the total effort of these groups is small when compared to the sum of the effort devoted to research by the individual .oil companies. In contrast to some industries which conduct the major portion of their research through co-operative, sponsored research at universities or research institutions, research by the petroleum industry is done predominantly by individual company research staffs. These industrial research groups have usually been organized in such a way as to provide liaison and co-ordination with operating technical staffs. In this way, the research groups are kept aware of the major problems confronting the operating departments and, correspondingly, the operating technical people •are able to keep informed on research activity and progress. This type of close contact generally results in prompt testing of research developments in actual operations."

Jan 1, 1953

By S. M. Bulatovic, D. M. Wyslouzil, K. R. Rawlings

"The suitability of a new organic reagent DS20 as a depressant for oxidized and carbonaceous pyritic lead-zinc ore from Nanisivik Mines Ltd. has been evaluated in the laboratory and in the plant.The depressant DS20 is a mixture of Lignosulphonate-Dextrin-Quebracho and was developed specifically for depression of highly oxidized and carbonaceous pyrite.The laboratory test work indicated that the poor metallurgy resulting from the oxidized ore could be improved to normal plant performance by the addition of the DS20 depressant with the existing plant reagents. The laboratory data suggested that lime consumption could be reduced when using DS20.In this paper, the development work and the plant trials with DS20 are described.INTRODUCTIONNanisivik Mines Ltd. treats approximately 2000 tonnes per day of lead-zinc massive sulphide ore, containing currently 1% Pb and 9% Zn. The concentrator operations have been described previously (1,2) and typical metallurgical performance is detailed in Table I.The concentrator flowsheet (Figure No. 1) and the standard reagent scheme (Table No. 2) demonstrate the relative simplicity of treatment of this coarse grained ore.A recently discovered satellite orebody - Area 14 - containing 2% Pb and 12% Zn was brought into production in October 1983. This ore had been oxidized to varying degrees by ground water; the pyrite mineralization was found to be very fast floating and a carbonaceous constituent present in higher than normal proportion also affected flotation. The simple high lime addition could not control the pyrite, and very low grade lead concentrates resulted; zinc metallurgy was also affected by this oxidized condition (Table 3)."

Jan 1, 1986

By M. A. Mahtab, A. S. Burgess, R. G. Charlwood, P. O. Sandstrom, J. L. Ratigan

"Addressing a current operating and environmental concern, this paper first presents an overview of the design program for an underground radioactive waste storage vault. It then reviews the construction, operational and thermal-mechanical aspects of such a project. The relevant experience from major underground construction projects is reviewed and the paper concludes with brief comments on the design-oriented research and development requirements . 1. IntroductionA program to develop techniques for the ultimate disposal of high-level radioactive waste into geologic formations was announced by AECL in 1975 (Tamrnernagi, 1976), and is discussed more fully in a later document (Boulton, 1978). Our paper summarizes the studies caried out, as part of the AECL waste management program, by the authors and associates on the development of design concepts for a vault situated in crystalline rocks of the type present in the Canadian Shield.The design studies have been carried out in three phases, the elements of which are described in Section 2.1 (also see Fig. 1). The general vault designs are presented in Section 2.2. These provide for emplacement of either immobilized fuel or solidified reprocessing wastes in a room-and-pillar facility at a depth of 1,000 m.Section 3 reviews the principal design considerations from the construction, operation and thermal-mechanical response aspects. The concepts have been studied in both temporal and spatial domains, and the requirements and responses assessed in each as appropriate.Section 4 briefly reviews the availability of relevant experience from previous major underground construction projects. Finally, in Section 5, brief comments are given regarding design-oriented research and development requirements."

Jan 1, 1980

By B. Skrotzki, E. Augenstein, C. Rockenhäuser

"The aluminium alloy 2618A is an Al-Cu-Mg alloy with additions of Fe and Ni, which is designed for long-term operation at elevated temperature in transportation and aerospace industries. The alloy degrades due to coarsening and dissolution of GPB zones and coarsening of S-Phase precipitates (Al2CuMg). This work investigates the overageing process at the application relevant temperatures of 190 °C for durations ranging up to 25,000 h. The nm-sized precipitates were selectively imaged along the <001>a direction of the Al matrix using dark-field transmission electron microscopy. The resulting images were then evaluated and allow the statistically relevant determination of radii distributions and the average radius of the precipitates dependent on temperature and heat treatment duration. Ostwald ripening of the S-phase does not describe the ageing process adequately. Instead, the evolution of GPB zones during the initial ageing regime needs to be considered in addition to the coarsening process of the S-phase. DSC measurements were performed to determine the presence of GPB zones in different ageing states. This will allow a quantitative description of the ageing process and a comparison to samples aged under external load.INTRODUCTION Alloy 2618A is an Al-Cu-Mg alloy, which is part of the 2XXX series of aluminium alloys. It is used in aerospace and transportation industry due to its desirable material properties for long term operation at elevated temperatures (Polmear, 2006). Fe and Ni are added to form intermetallic compounds, which retain microstructural stability at elevated temperatures (Bergsma, Li, & Kassner, 1996; Elgallad, Shen, Zhang, & Chen, 2014; Oguocha, Yannacopoulos, & Jin, 1996; Wang & Yi, 2006). The size and distribution of the nm-sized S-phase formed from the supersaturated solid solution (SSSS) during heat treatments mainly controls the strength (Khan, Starink, & Yan, 2008; Liu, Zhang, Ding, Sun, & Chen, 2003; Parel, Wang, & Starink, 2010; Shih, Ho, & Huang, 1996; Wang, Starink, & Gao, 2006). The S-phase has the composition Al2CuMg and is orthorhombic under equilibrium conditions (Heying, Hoffmann, & Pottgen, 2005; Perlitz & Westgren, 1943). Early experiments proposed the following decomposition of the S-phase sequence during heat treatments (Hardy & Heal, 1954; Silcock, 1961):"

Jan 1, 2018

"Eastern Canadian thermal coal mined at Minto, New Brunswick, and in western Cape Breton at St. Rose, Inverness County, Nova Scotia, contains 6-8 per cent sulphur. Both coals are high volatile bituminous. types. The Minto coal averages 18 per cent ash, 7 per cent sulphur and has a Btu rating of 11,900 per lb. Pyritic sulphur accounts for 75 per cent of the total sulphur and the remainder is largely organic; the amount of sulphate sulphur is negligible. This means that in a 7 per cent sulphur coal, 2 per cent is organic and 5 per cent pyritic sulphur. Pit-head St. Rose coal contains approximately 10 per cent ash, 7 per cent sulphur and 11 ,800 Btu/lb. The distribution of sulphur is different to that of Minto coal because about 12 per cent sulphate sulphur is present. Thus, a 7 per cent sulphur coal would contain 4 per cent pyritic, 2 per cent organic and 1 per cent sulphate sulphur.The iron sulphides, pyrite and, to a lesser extent, marcassite occur over a wide size range from large sulphur balls to crack fillings, lenses, and individual crystals and framboids. Coarse-grained pyrite and sulphur balls are easily separated during washing. It is the fine grain sizes, intimately mixed with the coal constituents, that are difficult to separate. Quantimet analyses of the fine grains in coal from both localities showed that about 50 per cent were smaller than 30 micron(1).No efforts have been made to wash the Inverness coal of Nova Scotia and in 1980 washing ceased in New Brunswick. Previously, the Minto coal was processed in an antiquated jig circuit which reduced ash from the strip operation run-of-mine value of more than 20 per cent to less than 18. More effective removal of ash and sulphur could clearly be obtained. Laboratory tests on both Minto and St. Rose coal have shown that ash rejection rates of 40 to 50 per cent at yields of 70-80 per cent were possible(2), Little information on sulphur removal was available."

Jan 1, 1981

By Barry D. Simmons

"A well-defined approach is essential to ensure the long-term success of a regional exploration program. Teck&apos;s approach in eastern Canada is designed to fulfill corporate objectives while recognizing certain unique parameters for exploration in the area. The elements of this approach include clearly defined objectives, technical considerations and personnel policies, all of which are equally important. The goal is a significant discovery before the mid-l990s and the company is confident that this target will be achieved.IntroductionAs one of Canada&apos;s oldest continuously operating mining companies, Teck Corporation traces its roots to Kirkland Lake, Ontario, with the development of the Teck-Hughes gold mine in 1913, later supplemented by production from the Lamaque gold mine in Val d&apos;Or, Quebec. Control of the company was acquired by Temagami Mining Company, part of the Keevil Mining Group, in 1959. Credited as one of the first discoveries made using airborne geophysics, the Keevil Group had recently found the small but very high-grade copper deposits at Temagami, Ontario. These developments in eastern Canada formed a foundation for remarkable growth and Teck&apos;s present status as one of Canada&apos;s most successful and respected mining companies.Teck currently operates successful mining ventures across Canada and has international exposure through its association with Cominco Ltd., M.I.M. Holdings Limited and Metallgesellschaft AG. Operations in eastern Canada, however, remain an important component of Teck&apos;s ongoing success. The David Bell and Williams mines at Hernlo, Ontario, are Canada&apos;s lowest cost and largest gold operations, respectively. The Niobec Mine at Chicoutimi, Quebec, is North America&apos;s only significant producer of niobium. Teck maintains a 45070 interest in Golden Knight Resources Inc., part owner of the successful gold mining operation in the Casa Berardi area of northwestern Quebec. As a significant shareholder in Aur Resources Inc. and as a part owner, Teck is participating in the development of the Louvicourt deposit, a major base metal discovery at Val d&apos;Or, Quebec."

Jan 1, 1992

By Kadir Sariiz

Abstract - The Akçayir-Yürükakçayir Miocene-Pliocene basin in the Central Anatolia hosts ancient lacustrine sepiolite deposits. The succession in this basin consists of conglomerate (Yürükakçayir conglomerate), clayey and silty limestone, dolomitic marl, sepiolite beds and lenses, and dolomitic limestone (Kepeztepe formation). The main impurities within the sepiolite rock are dolomite, opal-CT, calcite, smectite and feldspar as sepiolite + dolomite and sepiolite + opal-CT are the main mineral assemblages. Smectite and feldspar are thought to be of detrital origin. Calcite is found as a secondary filling in root tubes and casts. Sepiolite samples studied display root-marks and root tubes, soapy and massive structure indicating direct precipitation. Sepiolite deposits probably formed at a pH of 8 to 9, and Mg+2 and SiO2 concentrations in moderately saline environments of internal facies of an alkaline lake.

Jan 1, 2000

By W. Grell

"In this paper, two methods of standardizing mill language are proposed; one is based on metric units and the other on English units. Tentative procedures for chemical and screen analysis based on published methods are proposed.Standard procedures for determining work index, and for leaching, flotation, and classification tests are outlined.Objects of Standardization:(1) to improve communication -(a) among gold metallurgists(b) with other branches of mineral dressing(c) with mineral dressing in other countries(d) with general scientific procedure(2) to improve mill control by -(a) standard methods of analysis (i)(ii)(iii)(b) standard methods of calcula tiort(c) standard accounting proceduresin the plantin the mill laboratoryin the assay office(3) to improve mill test work and investigationAreas of Standardization(1) Nomenclature or terminology(2) Measuring techniques(3) Test procedures(4) Accounting procedures"

Jan 1, 1966

By George B. Saunders

It is the purpose of this paper to point out conditions as they exist in the merchandizing of coal, to compare these conditions with methods in use by competitive producers of coal substitutes, and to present briefly some suggestions which may help the individual operator to market more coal in the immediate future, while we are waiting for the scientist and research worker, who are now busy on coal betterment , to produce in a practical way the results which they now write about in such glowing terms. While it may be unnecessary to call the attention of coal operators to the present deplorable condition of the industry, it might be well to impress upon our members in other branches of mining, as well as upon the public at large, the seriousness of the situation. Emerging from the war and the period of reconstruction that followed, the coal industry found itself with too many mines and too many men for normal conditions. To make matters worse, the interruptions in deliveries caused by strikes, the unfavourable publicity caused by socialistic propaganda, and the repeated governmental investigations, made the market a fertile field for coal substitutes which were not so handicapped. These substitutes were well advertised, and were marketed in an up-to-date manner, furnishing an example from which the coal operator could well profit. Now, whether or not there is agreement as to the cause or causes of this condition, there can be no doubt that we are today face to face with the fact that the sale of coal has not kept pace with the sale and use of other commodities. Had it done so, we would ere this have been able to take care of the surplus labour and work our mines at least approximately full time.

Jan 1, 1929

By J. H. Baek, D. W. Lee, B. K. Kim

Nanostructured Cu-Al203 composite powders were synthesized by thermochemical process for an electrode application. The synthesis procedures are 1) preparation of precursor powder by spray drying of solution made from copper and aluminum nitrates, 2) heat treatments to evaporate volatile components in the precursor powder and synthesis of nanostructured CuO+Al2O3, and 3) CuO reduction by hydrogen into Cu. The suggested procedures stimulated the formation of the gamma-Al2O3. The mean particle size of the final composite powders was 20nm, and the electrical conductivity and hardness in the hot-extruded bulk were competitive with Cu/Al2O3 composite by the conventional internal oxidation process.

Jan 1, 2004