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By N. Ohmura, H. Saiki, T. Nagaoka

A microbiological flotation system that facilitates the removal of pyritic sulfurfrom coal is reported. The chemoautotrophic bacterium Thiobacillus ferrooxidans is utilized as a pyrite-selective biological surfactant that augments the flotation-mediated rejection of pyritic sulfur. The bacteria were produced by continuous cultivation in 50-L tanks, where it was possible to produce 3.8 x 1012 cells/day when the dilution rate was optimal and the pH was 1.6, a condition that prevented ferric precipitation. Prior to flotation, the bacteria were mixed with coal, which allowed cells to selectively adhere to the pyrite. The adherence of bacteria made the pyrite surfaces more hydrophilic, which facilitated separation by increasing the tendency of pyrite to sink, while the hydrophobic coal floated. When a synthetic coal/pyrite mixture (10.1 % sulfur) was subjected to microbial flotation, the level of sulfur rejection was stable during the entire period of operation (i.e., one hour). In the absence of bacteria, flotation reduced the sulfur content of a coal/pyrite mixture to within the range of 6.7% to 7.4%, with the combustible recoveries ranging from 93.9% to 99.0%. In the presence of bacteria, the sulfur content of cleaned coal was in the range of 1.3% to 1.4%, with the combustible recoveries ranging from 80.8% to 86.3%. Bacterial activity accounted for 57% of the total sulfur rejected through flotation. The desulfurization capacity of the system was further confirmed by testing it with run-of-mine coal. The pyritic sulfur content was reduced from 2.9% in the feed coal to around 1.2% in the froth product, while 80% of the combustible recovery was retained. Microbial flotation removed 60% of the pyritic sulfur from the feed. These findings demonstrated that micro¬bial flotation could be utilized for the removal of pyritic sulfur from coal in a semicontinuous system.

Jan 1, 2000

By D. R. Derry

"IT WOULD TAKE a braver man than I to try to forecast the future of mining exploration far into Canada's second century. Even to look ahead ten or twenty-five years we must review the figures of the fairly recent past -and I have found this quite a time-consuming but interesting job -in order to find trends and project them into future years. The trends to which I will refer are: firstly, the annual expenditure on exploration and its relation to value of output; secondly, the discovery rate and its relation to production initiations; and thirdly, the methods by which discoveries have been, and will be, made. Exploration Expenditures Figures on the annual expenditure on mining exploration in Canada have been collected and published for some years by the Do-minion Bureau of Statistics. These have some unavoidable limitations; e.g., in the varying definition between one company and another of what comprises ""Exploration"" and in the difficulty of getting complete returns. However, although the actual figure for a given year may be subject to question, I believe that the relative figures from one year to another are reasonably reliable. There is also a lapse of time between the collection of data and publication -the last published figures are for the year 1963. In bringing the figures up to date to 1966 I have canvassed eight of the larger mining and exploration companies and obtained their figures for 1963 to 1966 inclusive, and then averaged these for each year and applied the progression to the 1963 figures."

Jan 1, 1968

By Hendrix J. L, Nelson J. H

A model based on non-steady state has been developed for dissolution and diffusion in porous ore particles. Results from the particular model have been incorporated, as a rate term, into a global, heap-scale model based on a plug flow reactor at unsteady state. The global model can be used to consider leaching by aqueous-phase reagents in equilibrium with a gas- phase component, such as oxygen gas, as well as strictly aqueous-phase reagents, such as cyanide. The flexibility of the model even allows predic- tion of the outcomes of using reagent sideflow injection in large heaps. Data from column leaching tests are compared to the model, and their relationship is discussed.

Jan 1, 1991

By H. C. Doepken

Wrought Hadfield steel was tested in axial tension at from 100° to —196°C, to determine flow and fracture stresses as well as conventional properties. Ductility and related properties, such as fracture stress, decreased continuously with temperature. Peculiarities during straining indicated possible martensite formation or mechanical twinning. THE mechanical properties of austenitic manganese steel have been summarized by Avery and Day,' including the low temperature tensile properties reported by Hadfield and coworkers2,3 " These data show the material to be brittle at both liquid oxygen and liquid 'hydrogen temperatures. Avery and Day report considerable ductility measured by Charpy V-notch tests at —100°F (-73°C). Since the review of low temperature properties by Seigle and Brick' show face-centered cubic structures, other than Hadfield steel, to be ductile at low temperatures, it was felt that a study of tensile properties, between the reported intervals, should show whether the decrease in ductility was a gradual decline or an abrupt drop beginning at some intermediate point. X-ray examinations were made in an attempt to shed further light on the mechanism of work hardening of austenitic manganese steel. The presence of a magnetic constituent has been found by Hall" and by Avery, Homerberg, and Cook." Krivobok7 demonstrated the growth of magnetic constituents on reheating cold-worked specimens. Hadfield2,3 ' and Goss found no a iron. The steel from which the specimens were taken was commercial hot rolled % in. diam rod of electric furnace steel. The ladle analysis was as follows: C, 1.40 pct: Mn, 12.11; P, 0.060; S, 0.012; Si, 0.120; Ni, 0.080; and Cr, 0.090. Fifteen specimens, 6 in. long, were cut from a

Jan 1, 1953

By Wu H. W, Jones S. J

Australia wide, over 40 fly-in/fly-out mining operations and other forms of long distance commuting now exist, with coverage of about 5000 employees. The substantial majority of these operations are in Western Australia, with some mines also located in Queensland and the Northern Territory. In recent years new large-scale mining operations have adopted the fly-in/fly-out approach and it is important to note that no new mining towns have been constructed in Australia since the township of Roxby Downs was built in the late-1980s to service the Olympic Dam mine. An examination of fly-in/fly-out mining operations in Australia has been undertaken. A detailed survey undertaken in 1990 has been reviewed and another intensive survey undertaken to establish emerging trends. Results from both company and individual employees point of view have been analysed. A section examines the views of professional employees and the influence of fly-in/fly-out on career development. Bus-in/bus-out coal mining operations are emerging in Queensland's Bowen Basin. These operations commute their employees into the mine site for compressed working schedules while the mine employees' families are domiciled in regional cities such as Mackay. A review of the issues associated with the development of long distance commute coal mining operations in Queensland's Bowen Basin is performed and two case studies examined.

Jan 1, 1997

By Crook KAW

New sedimentological and biostratigraphic data indicate that the Leron Formation in the Markham Suture Zone, Papua New Guinea (PNG) represented Pleist- ocene alluvial fan-delta deposition in shallow marine to lacustrine environments. The distribution of sedimentary regimes in the Leron Formation indicates that during collision zone evolution, various tectono-sedimentary regimes do not always track the movement of the triple-junction systematically as idealized by Crook's (1989a) model. The migration of various tectono-sedimentary regimes are also controlled and influenced by the effects of second-order geometric features of the convergent margins. Leron Formation in the Markham Valley represents late to post-collisional marine to fluvial molasse. Foraminifera indicate that the collision and concomitant suturing of the Markham valley occurred after 1.32Ma.

Jan 1, 1991

By R. D. Miller, D. W. Steeples

Application of shallow, seismic reflection to problems associated with mineral exploration, mine planning, abandoned-mine detection and environmental evaluation has been successful in many geologic settings. The increased dynamic range of recording equipment and the decreased cost of processing hardware and software have made shallow, seismic reflection a cost-effective means of imaging geologic targets significant to mining operations. Seismic data possess sufficient resolution in many areas to detect faulting with displacement of less than 3 m (10 ft) in coal seams as thin as 2 m (6.5 ft) at depths of 200 m (655 ft). Subsurface voids associated with abandoned mines at depths of less than 20 m (65 ft) can he detected and mapped. Seismic reflection has been successful mapping disturbed subsurface associated with dissolution mining of salt. Complex geologic features associated with deposition of various hydrothermal minerals have been mapped with high-resolution seismic reflection at depths from 80 m (260 ft) to more than 300 m (985 ft). Faults in sulfur-hearing cap rock over salt domes have been accurately located, allowing improved efficiency of the dissolution mining process. Shallow, high-resolution seismic reflection has the potential to enhance the economics and safety of mine operations.

Jan 1, 1996

By H. O. Poppleton

This Bureau of Mines study was made to investigate a possible method for selectively removing the Si02 component of silicate minerals and ores. Of specific interest were aluminum ores and zircon. Methods are described for removing Si02 from these ores as volatile silicon sulfides by treating the ore with sulfur and carbon; with sulfur, carbon, and a reducing gas; or with sulfur compounds and carbon. Comparative results are also given for the desilication of some of the ores with carbon alone to form volatile silicon monoxide. The silica component can be removed partially from bauxites at temperatures above the sublimation temperature of SiS (940° C) by treatment with carbon, sulfur, and methane; however, it is more difficult to remove the silicon from kyanite, manganese silicate, red muds from aluminum processing, kaolinite, lateritic nickel ores, and zircon. Complete desilication requires temperatures ranging from 1,100° C for bauxite to 1,450° C for zircon. Although the high temperatures required and the undesirable metal sulfides produced eliminate practical application of this method using present technology, the Bureau is reporting this data so that they will be available to future investigators.

Jan 1, 1974

By Olga K. Karakasi, Angeliki Moutsatsou, Ioanna Kavallari

"The present study focuses on the amelioration of the behaviour of high calcium fly ash (HCFA), investigating its application in a new environmental field: oil spill clean up. High calcium fly ash is a by-product of electric power plants, produced annually in large quantities, whose greater amount is landfilled. Some of its properties, such as its chemical and mineralogical composition, its fine particle size, its porosity, floating ability and hydrophobic character make it an attractive material for this purpose. Researches showed that when added to an oil spill, it forms a semi-solid phase, which allows the quite total removal of the oil, but it is not stably retained on the surface. In order to ameliorate its floating ability, the decrease in its specific gravity by mixing with a lighter material is investigated. In the present study the mixing with two materials, already used in oil spill clean up, sawdust and a polymer, has been examined. Addition of 15-25% w/w sawdust to HCFA results in a material with better performance than HCFA or sawdust alone: it has a satisfactory floating ability and allows total removal of oil. Addition of the polymer, however, has resulted in no significant amelioration of the oil sorption behaviour of HCFA, probably because no affinity between HCFA and polymer has been achieved.IntroductionCoal fly ash is a by-product of coal combustion in electric power plants, produced worldwide in huge quantities, approximately 500 million tones annually. High calcium fly ash (HCFA) is classified to class C presenting a (Al2O3 + SiO2 + Fe2O3) > 50%. The production of lignite fly ash in Greece comes up to 13 million tones annually, of which only 12% is used in construction applications, the other being landfilled [5, 6].Besides its limited application worldwide as a construction material, research is focusing on the development of new environmental applications, such as waste stabilisation and solidification, soil and water environmental improvement [9, 12]. For the application of fly ash in further environmental fields several chemical modifications have been applied, in order to improve its properties. Extensive research has been focused on the conversion of both coal and lignite fly ash to zeolite and its further application in environmental field, such as the uptake of inorganic (heavy metals and ammonium [8, 11]) or even organic compounds (methylene blue [15]) from waste water streams, or the use as molecular sieves, to adsorb water molecules, SO2 and NH3 from gas streams, due to the high cation exchange capacity and porosity of the produced zeolithic material. Furthermore, lignite fly ash has been combined with sodium silicate solution, prepared by treatment of rice husk ash, and tetrapropylammonium bromide, to synthesise hydrophobic zeolite ZSM-5 [4]."

Jan 1, 2008

An International Ferro-alloys Congress, arranged by the Ferro Alloy Producers' Association of South Africa, the South African Institute of Mining and Metallurgy, and the National Institute for Metallurgy, will be held in Johannesburg, South Africa, in April 1974. The technical programme, occupying five days, will cover the following topics in relation to all ferro-alloys: 1. Burden preparation, blending, pelletization, handling, reducing agents. 2. Electric smelting furnaces-design, operation, management,- smelting optimization, shop practice, refractories. 3. Mineralogy, reduction behaviour, smelting reactions, slags. 4. Automation, Pollution control. 5. Applications, trends in comsumption, trends in composition specifications. There will be no parallel sessions. Papers in the above topics are invited; review papers will also be welcome. Proposed titles and abstracts in not more than 200 words should be submitted before the 30th of November, 1972, to The Chairman, Programme Committee, INFACON 74, Private Bag 7, AUCKLAND PARK, South Africa. The abstracts will be considered during January 1973, and papers accepted for the Congress must be submitted in final form before the 31st of July, 1973. The proceedings of the Congress will be published as a special volume. There will be a series of post-Congress tours to ferroalloy plants and other places of both technical and scenic interest. A full ladies' programme will be arranged. The First Circular, giving further details, can be obtained from: The Secretary of the Organizing Committee, INFACON 74, Private Bag 7, AUCKLAND PARK, South Africa.

By C. O. Dale, W. J. Rundle

THE upper Mississippi Valley zinc-lead area was the first major lead producing section in the United States. The lead ore, found near the surface in crevices, was relatively pure galena that could be smelted directly into lead, at first in log hearth furnaces and later in more efficient blast type furnaces. French Canadian fur traders encouraged the Indians to mine the lead ore and showed them how to smelt it into lead that had a high value for bullets.1 Nicholas Perrot found lead ore on the Mississippi River bluffs near the junction of Wisconsin and Illinois and in 1690 established a trading post on the Wisconsin side of the river opposite the present site of Dubuque, Iowa.2 Shortly after 1720 discovery of Mine La Mott in Missouri diverted considerable attention from the Upper Mississippi area. Mining continued on a desultory basis with operations concentrated in the Galena, Illinois-Dubuque, area. In 1740 at least 20 miners were at work in the Fever River area around Galena and are reported to have shipped 2500 70-lb pigs of lead to Kaskaskia in 1741.3 Julien Dubuque established a mining and smelting operation in 1790 near the city that bears his name 'and was granted sole right to exploit the mining operations on the lands of the Sauk and the Fox Indians. He is reported to have produced 30,000 70-lb pigs of lead in 1805. Following the death of Dubuque in 1810 the Indians refused to let the white miners enter their lands, and little was done on the Iowa side of the river until the Indians were removed by treaty with the United States government in 1832.4 Early mining was entirely for lead but as the crevices were followed down, increasing percentages of zinc sulphide and zinc carbonate were encountered and at first discarded. Later a market became available for the zinc ores, and hand jigging devices were made to separate the lead," the zinc, and the rock or waste materials. The first record of zinc production from -the area is for 1860. Production of zinc passed that of lead before 1900, reached a peak of 64,000 short tons' in 1917, fell off rapidly and continually to about 2000 short tons in 1938, and since 1940 has ranged from 11,000 to 19,000 short tons. Lead has been of considerably less importance since 1900, and at present only about 10 pct as much lead as zinc is produced. Practically all of the zinc ore has come from orebodies that are rather flat and wide with, considerable length as compared to width. Most of the early lead came from the crevice type deposit, but present production is from the predominately flat zinc orebodies. The Graham-Snyder orebody, scene of Eagle Picher operations, is practically all zinc with little or no lead being recovered. Marcasite, present in varying amounts, makes production of finished concentrates by gravity separation impractical. Satisfactory lead and zinc concentrates have been produced since flotation was introduced in the area in 1927. An acid recovery plant was operated for about 20 years after World War I, but it has been dismantled, and no recovery of the iron sulphides in the ores of the district is being made at the present time. In June 1950 there were three companies operating mines and mills, Tri-State Zinc Co., Calumet & Hecla Consolidated Copper Co., and Eagle Picher Mining and Smelting Co. The Vinegar Hill Zinc Co. had completed a shaft at a new orebody and had started to develop the mine which will supply the Cuba City mill. The Cuba Mining Co. was holding the Andrews Mine inactive. The Dodgeville Mining Co. was not operating but was exploring for additional reserves. Several small mines were selling ore to the Eagle Picher mill. A general area map is given in Fig. 1. The Eagle Picher Mining and Smelting Co. entered the area in 1946 with an active exploration campaign. Leases on a block basis were secured for the area south from the Wisconsin-Illinois line near

Jan 1, 1952

This paper discusses the impacts that advances in metallurgy and process engineering have on minerals project execution. Ausenco's business is focused on integrating minerals processing technology and the delivery of cost effective processing plants that exceed client performance expectations. The metallurgical development is a small but critical part of this process. Metallurgical development and innovation outcomes need to be transformed into an engineered solution and that solution converted into an operating plant in a cost conscious and competitive environment. Including new or innovative processes in a project flow sheet increases a project's technical and commercial risk. However, it also gives the project, and/or the engineering company, a potential advantage over projects using mainline practices. Managing the balance between risk and opportunity has been a cornerstone of Ausenco's success in recent years. Some advances in "technology" that are discussed in the paper include: larger capacity equipment new flow sheet concepts simplification of process interfaces, and more effective project strategies The common theme is that having a new idea can be the easy bit, putting it into operation effectively involves numerous people, many interfaces and strong project management.

Sep 13, 2010

In considering the preparation of any paper concerning bearing metals, one feels a certain amount of diffidence in venturing into a field which has been capably explored at great length and in great detail during recent years. Many excellent articles have appeared in technical literature, dealing with the general theory of bearings and of bearing metals, the properties of white metals of the tin-base and lead-base types, and of the recently developed lead-bronzes.The justification for this further excursion into the field lies in the fact that it treats a branch of the bearing metal family which has so far received very little attention, and that of a somewhat sketchy nature, in published papers.The author's object is to give some outline of the history, development, present status and possibilities of the cadmium-base bearing metal alloys, particularly those in which copper is the main alloying element.GENERAL CONSIDERATIONS.It is desirable that attention should first of all be given to the general theory, constitution, and necessary attributes of bearing metals, in order that some of the problems met with during the development work may be better appreciated.Despite some evidence to the contrary, it is fairly generally maintained that an alloy for bearing metal use should be of a heterogeneous nature. It should consist of particles of a hard constituent uniformly distributed through a softer matrix.The basic idea is that the hard constituent should actually bear the load and resist wear, while the matrix imparts the necessary ductility and allows the bearing to align itself on the shaft in service.

Jan 1, 1934

By M. Albertson

AT Cobalt, Ontario, Canada, a lake was drained to facilitate mining, by the Mining Corpn. of Canada, during the spring and early summer of 1915. Previous to pumping out the water, great quantities of sands and slimes from concentrating plants had been discharged into the lake and during and after the lake's drainage, its basin' Was a receptacle for tailing products. As the writer was at work along the shore line as the lake was being drained, he had a good opportunity to observe the changes that took place as the water was withdrawn. Some adjustments between the incoming sands and the mud in the lake had taken place before pumping was commenced. One of the most interesting results was the appearance of a small dome in a path the writer traversed twice a day for several months; he remembers distinctly the difficulty of crossing this. Cobalt Lake owed its existence to the gouging out of a rock basin by glaciation. The long axis of the basin closely follows the strike of a thrust fault of about 500 ft. (160 in.) vertical displacement. The lake was originally shaped somewhat as shown. The length was about 3000 ft. (914.4 in.), the width at the lower lobe was about. 1000 ft., and the, width at the narrows probably. 400 to 500 ft. The original depth of water varied from 20, to 30 ft. (6.1 to 9.1 m.), near where the island later was formed, to 60 to 70 ft. (23.6 to 27.6 m.) in the widest part of the lower lobe. At the narrows, the depth was 30 to 40 ft.. Above the bed rock was sand, with boulders near the bottom, and mud. During the building of the railroad in 1903, considerable filling was done along the right of way. With the commencement of mining operations, about 1905, waste rock and mill tailings were dumped into the lake. One of the mining companies operated a hydraulic giant to remove the glacial debris from several hundred acres of rock surface; much of the sand and clay from this operation was deposited in the. lake. About

Jan 2, 1921

By Alexis Baca

La presente investigación busca optimizar la producción y la ventilación en la industria minera, utilizando el método de ratios de energía y producción. Para ello, hace la estimación del consumo de energía en ventilación, obteniendo los ratios de producción en la unidad Huarón y aplicando estos para determinar la eficiencia del consumo en cada zona, logrando un comparativo de costos para conseguir una distribución eficiente de la ventilación. Asimismo, recomienda formas de optimizar el consumo de energía por ventilación mediante el uso de los ratios de energía y producción.

By Gunder Homstvedt

The paper presents a new method for boring of blind inclined shafts. The machine, called BorPak, developed by The Robbins Company, operates similar to a mini TBM. It is a remote operated, self propelled drilling machine mounted on a crawler for high mobility and launched out of a starting tube for quick collaring. A short history of the operation of the prototype in Scandinavia and Canada is included in the paper. The BorPak is capable of boring raises at angles from 30° to 900 from horizontal in sizes ranging from 1.2m-2m diameter without the use of drill pipe. The BorPak represents an innovative tool for improved performance, reduced costs and creating a safer working environment.

Jan 1, 1993

In 1988, at the request of members of the Society for Mining, Metallurgy, and Exploration (SME) Inc., the president of SME formed Working Party No. 79, Ore Reserve Definition. Its mission was to develop guidelines for the public reporting of exploration information, resources and reserves. These guidelines were published in the April 1991 issue of Mining Engineering (pp. 379-384), and as a document entitled “A Guide for Reporting Exploration Information, Resources, and Reserves” in January 1992. Work continued on an ad-hoc basis until 1996. Working Party No. 79 was then renamed the SME Committee on Resources and Reserves and became a standing committee.

Jan 1, 1999

By Atsuki Sado, Akira Ueno, Kazuaki Takebayashi, Kunio Watanabe

The Saganoseki Refinery of Pan Pacific Copper Co., Ltd., Japan, introduced the ISA 2000® process in 2006 to improve product quality and productivity. After resolving various technical difficulties associated with the process, a current density of 325 A/m2 and electrolytic copper production of 234 000 tons per year were realized in 2018. In recent years, Saganoseki Smelter & Refinery has promoted treatment of recycled materials in addition to copper concentrates. Accordingly, the amount and type of impurities charged to the smelting process have tended to increase. In the electrorefining process, impurities such as nickel and antimony cause anodic passivation and formation of suspended solids, respectively. Although these undesirable phenomena can be avoided by controlling impurity concentrations in the anode and electrolyte to appropriate ranges, this also limits the choice of recycled materials that can be processed by the smelter. To achieve both stable operation of the electrorefining process and flexibility in treatment of recycled materials in the smelting process, Saganoseki Refinery improved the capacity of the impurity recovery processes during 2016 to 2018. This paper describes the expansion of the purification plant to remove and recover nickel and antimony. INTRODUCTION The Saganoseki Refinery of Pan Pacific Copper Co., Ltd., Japan, introduced the ISA 2000® (wax- less permanent cathode method) in 2006 to improve product quality and productivity. Since then, the refinery has gradually increased current density, and has been committed to establishing stable operation and high productivity via various improvements related to the electrolyte filtration and additive management systems. Figure 1 shows the trends of current density and current efficiency at the refinery. Although the current efficiency temporarily dropped when the current density was raised to 322 A/m2, it consistently exceeded 97% thereafter. At present, stable operation at 325 A/m2 has been achieved and continues.

Jan 1, 2019

By W. R. Paterson, W. Morton, D. B. Cameron

The Massbal II computer simulation program has been used to develop a general framework for the building of thermochemical models of metallurgical processes. The framework allows the rapid, simple construction of complex models of process equipment for use in flowsheet design, planning and plant operation. Application of the program to model the iron-making blast furnace and a flash smelting process is described

Apr 1, 1991

By John B. Riddell

"AN EXCELLENT review of the status of applied geochemistry was given by Warren (1959) at last year's General Meeting of the C.I.M. The purpose of this paper is to present recent developments and trends. Several important books were announced during 1958: Ginzburg, I. I. Principles of geo-chemical prospecting. (In process of translation from the Russian by V. Sokoloff).Vinogradov, A. P. The geochemistry of rare and zvidely scattered chemical elements in soils. Consultants Bureau, N.Y. Korzhinskii, D. S. Physicochemical basis of the analysis of the paragenesis of minerals. Consultants Bureau, N.Y.In addition to these translations Mason's Geochemistry' has been revised, and Hawkes and Webb (personal communication) are publishing a book on geochemical exploration. A Symposium on Geochemistry was head in Paris in July, 1957, in conjunction with the XVIth International Congress of Pure and Al-lied Geochemistry. The abstracts of the papers presented at this Symposium were published in Geochimica et Cosmocl1imica Acta, 1958, Vol. 14, pp. 150-167."

Jan 1, 1960