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By N. A. D. Parlee, I. D. Shah, W. C. Phelps

THIS note reports on a continuation of a program on the thermodynamics of Fe-S-X systems in the "steel-burning" temperature range begun by Bock, Barloga, and parlee.' Small coils of 0.039-in.-diameter pure iron (Ferrovac-E) wire were equilibrated with Fe-S-0 melts in ingot iron crucibles under argon at 1324°C in the assembly shown in Fig. 1, the lower part of which was heated in a large Globar furnace. Fig. 1 shows (R) the coiled iron wire sample, (M) the Fe-S-0 melt prepared from desired proportions of ferrous sulfide and ferric oxide, (K) the iron crucible, (I) a mullite guide tube, (J) an alumina crucible, (L) alundum sand, (N) crushed mullite, (Q) hollow cylinders of K30 brick, (C) a steel rod, (B), (El, (F), (G), (P), and (O), details of brass water-cooled head, and (H) a mullite tube 2-3/4 in. ID and 26 in. long. The rod (C) bearing the sample could be removed at will and be replaced by a tube for sampling the melt, or by a thermocouple for comparing the melt temperature with a control thermocouple not far from the 2-3/4-in. mullite tube. After equilibration the iron coils were treated with acid to remove the outer layer of metal and then they were analyzed for sulfur by a standard combustion method. The melt samples were analyzed for oxygen by a variation of Lander's2 hydrogen-reduction method for mattes, and for sulfur by the ASTM combustion-iodometric method NO. E 30-47. When the results of some forty-two runs were examined it was found that the sulfur and oxygen contents of the equilibrated melts showed good consistency, in that the plotted compositions fell along the smooth curve shown in Fig. 2. The points on this curve represent the experimental compositions of melts in equilibrium with ?-iron (Fe-S-0) solid solutions. These solid solutions are saturated with sulfur and oxygen with respect to the melt and therefore have the same sulfur and oxygen activities as the melt. The curve drawn through the points therefore delineates the ? liquidus. It falls in such a position as to roughly confirm the liquidus curves of Hilty and crafts3 at 1200" and 1300°C which are

Jan 1, 1965

Although bismuth mineralization is spread widely through the Lachlan Fold Belt in New South Wales, broad grouping of the various deposits can be effected on the basis of geographical and geological (age and type of associated rocks) affinities. As a result, significant concentrations of bismuth can be recognized in the Mid-Western granites, Cobar-type ore, the Yass Silurian acid volcanic belt, and the Albury, Bega, Braidwoodand Bathurst districts.In these deposits bismuth generally occurs in minor amounts associated with molybdenite, wolframite, scheelite, cassiterite, chalcopyrite, galena, magnetite, pyrite, arsenopyrite, and native gold. From this group of minerals three broadly defined associations can be recognized.I. Bi-Sn-W-Mo2. Bi-Au( -Te)3. Bi-Pb-Cu(-Au)There may be some interchangeability of these metals, as instanced by occasional Bi-Cu-W-Mo mirleralization, but pyrite and/ or arsenopyrite are usually prominent in all associations.The first two of these associations occur mainly in the form of narrow quartz veins rarely averaging more than O· 3 per cent Bi, although there is often a marked enrichment in ferruginous material in the oxidized zone.Most of these veins occur within or adjacent to granitic rocks of varying ages (principally Silurian or Devonian), although Bi-Au mineralization tends to be related to more basic igneous activity than the Bi-Sn-W-Mo association.The latter is also occasionally developed in pipes, usually coarse-grained and richer in bismuth (as at Whipstick, the principal mine in New South Wales with a production of 343 tonnes of the metal), or in lower grade, but probably larger tonnage skarn deposits. The bismuth-base metal association occurs mainly in Silurian acid volcanic sequences and may also form low grade but large tonnage deposits, such as is possibly developed at Cobar.

Jan 1, 1973

By Patrick Polk

For many years, sulfuric acid producers all over the world have been forced to meet ever more strict environmental regulations to reduce SO2 emissions. The sulfuric acid industry has implemented new solutions in order to comply with the new lower SO2 emissions target. Haldor Topsoe (Topsoe) has responded to this challenge by continuously improving the range of VK sulfuric acid catalysts and providing tailor-made catalyst solutions to meet the demands of the sulfuric acid producers for lower SO2 emissions. Reducing emissions through catalysis: requires less capital than installing a scrubber, requires no additional process chemicals, generates no waste or by-product to dispose of. In 1996 Topsoe introduced VK69, a cesium-promoted vanadium catalyst, designed for operation in the pass(es) after the intermediate absorption tower in double absorption plants. The high activity of VK69 allows for a more than 50% reduction in SO2 emissions from existing double-absorption plants. Topsoe currently has more than 110 installations of VK69. To comply with the still more stringent regulations being placed on the sulfuric acid industry to lower SO2 emissions, Topsoe has developed a new sulfuric acid catalyst designated VK-701 LEAP5™. This catalyst was introduced to the market in 2010. VK-701 LEAP5™ is based on a novel technology which circumvents the internal transport deficiencies of existing commercial sulfuric acid catalysts and thereby offers exceptionally high activity in strong, SO3 rich gases. Sulfuric acid plants have used this catalyst to meet emissions requirements lower than previously believed possible with a catalyst only solution. This paper will present examples on how to reduce emissions by implementing a tailor-made catalyst solution using VK69 and VK-701 LEAP5™.

Jan 1, 2014

By A. Kostin

GIS and multivariate geometric distribution have been used to predict the association of high-level intrusives with hydrothermal alteration related to iron oxide Cu-Au (IOCG) mineralizing systems. Several examples in the Russian northeast are presented in this paper. IOCG ore deposits can have enormous geological resources containing significant reserves of base, precious, and strategic metals, and hence are economically attractive targets for mineral exploration. To date, examples of this type of mineralization have not been reported from the northeastern area of Russia. The Tarinskiy ore cluster, located in Eastern Yakutia, shows brecciated altered rocks with sulphide and iron oxide cement, which is typical for IOCG mineralization of the iron oxide Cu-Au±U type. This cluster was formed near surface and is linked with the Rep- Yuruinskiy pluton. It has potential to host new world-class precious metal deposits in northeastern Russia

Jan 1, 2014

Study on Influence that Styrene-Phosphoric has on the Surface Property of Rutile Minerals

Sep 13, 2010

By P. N. Anyalebechi

The effects of Si (0.19-0.52 wI. %), Fe (0.20 wI. %-0.44 wI. %), and Cr (0-0.10 wI.%) on the response of ingots of aluminum alloy 3004 solidified at different rates (O.IO°C/s to 30°C/s), to homogenization heat treatment have been investigated. Response to homogenization was determined by quantifying the following microstructural parameters: (i) amount of Mn retained in solid solution; (ii) types, relative amounts, sizes, size distributions, shapes, and chemical compositions of second phases; (iii) extent of the alpha-transformation (i.e., AI6(Fe,Mn) --7 (XAI12( Fe,MnhSi) reaction; (iv) dispersoid formation; and (v) alleviation of dendritic microsegregation. Of the three alloying elements investigated, Si had the greatest effect on the response of aluminum alloy 3004 to heat treatment. Increase in Si content, fineness of cast microstructure, and homogenization temperature facilitated alpha-transformation reaction, dissolution of Mg2Si, loss of Mn supersaturation, and formation of AldFe,Mn)3Si and Mg2Si dispersoids.

Jan 1, 2008

By A. A. El-Midany

Traditionally, the choice amongst different upgrading techniques or in finding the optimum operating conditions for a given upgrading technology depends on whether one is looking at the grade or the recovery of the valuable mineral in the concentrate. In fact, the conclusions are not usually the same. This is because the best technique or optimum operating conditions for the highest grade are not the same as the conditions to achieve the maxi-mum recovery. Therefore, a unique measure that takes into consideration both grade and recovery is urgently needed. Finding such a measure is the objective of this paper. A proposed measure provides a selectivity index in the range of 0 to 1, where 0 is no selectivity and 1 is ideal selectivity. The index can be obtained by plotting the so-called Fuerstenau upgrading curve, which relates the recoveries of the components in products of separation and a running regression applying a one-parameter equation. The measure was applied to assess the selectivity of selective flocculation under different operating conditions when used as a sensitive upgrading technique for ultrafine ground ores. After applying the proposed selectivity measure in the case of the selective flocculation of ultrafine Egyptian iron ore without the addition of cations, it was found that the optimum conditions are pH 11, 1 kg/t sodium silicate and 0.4 kg/t potato starch with a selectivity index of 0.55. With the addition of cations, the optimum conditions were found to be pH 11, 1 kg/t sodium silicate and 2 kg/t potato starch with a selectivity index of 0.65. It should be noted that determining these optimum conditions using the traditional grade or recovery measures was highly ambiguous.

Jan 1, 2008

By R. Bitmead, R Barker, A. Drake

The opencut coal mine is located about 50 km west of Brisbane, the capital city of Queensland in Australia and produces about 140 000 tonnes per annum of high grade steaming coal utilising a small team (ten) of personnel to mine remnants of the Aberdare and Bluff seams left by previous underground mining. This, in itself, is not remarkable except that one of the seams has commenced spontaneously cornbusting resulting in temperatures in excess of 55’C commonly being encountered with portions of the p’it being wreathed in steam. To extend mine life, the mine required a blasting system that would: . Safely blast in temperatures below 100°C . Significantly reduce overall unit costs . Not increase the current vibration impacts on nearby housing . Not increase flyrock.

Jan 1, 2002

Greater use should be made of lineations in investigations of the engineering properties of rock masses and in structural studies guiding prospecting programmes.A prominent alignment of elongate mineral grains and stretched pebbles usually marks the primary direction in which metamorphic rocks have been extended by flow. In local adjustment zones separating masses that have extended different amounts, this lineation has been a direction of slip. Kinks and crumples resulting from this slip lie in secondary lineation directions transverse to the primary mineral lineation.During deformation relatively mobile materials move into dilatant zones caused by irregularities in primary flow directions. This secondary movement transverse to lineated, primary-flow directions is the cause of crenulations and folds with axes parallel to flow lineations.INTRODUCTIONThe arrangement of inequidimensional particles in rocks is rarely statistically random. Platy minerals tend to be parallel to bedding and foliation planes. Elongate particles and linear structures lie most frequently in certain lineation directions. The types of elongate particles in lineated rocks include needle and blade shaped mineral grains, sheared out segregations, and stretched pebbles, amygdules, and aolites.Crenulations and kinks are the most common of the linear structures involved.Faint lineations are readily overlooked. Even strong lineations have been ignored. This is unfortunate as even weak lineations may be important.Use of lineation information Well-developed lineations influence the mechanical properties of rocks. Quarry workers have long known that the mechanical properties of rock masses vary directionally...

Jan 1, 1965

A regular general meeting of the Canadian Mining Institute will be held in Vancouver, B. C., on Nov. 26-28. The Council extends a cordial invitation to all members of the American Institute of Mining and Metallurgical Engineers to attend.

Jan 11, 1919

By Brown H. R, Wright E. A

The authors identify the workable coal seams, their distribution in relation to quality and economic occurrence and relate their analytical characteristics to industrial use. The development of established collieries is also discussed with regard to increased production demand.The authors also indicate the potential of the coal resources of the Southern District and postulate their ultimate development.INTRODUCTIONThe Southern Coalfield yields 30 per cent of the total production of bituminous coal in New South Wales. The economic potential of the coalfield was examined last by Harper (1915). Since that time additional knowledge has been gained by prospectors, mining companies and public authorities. Expansion in the steel industry and the building of power stations on the coalfields together with improvements in fuel technology, mining methops and road transport have resulted in production of coal from seams mice thoughtto have no economic value.DESCRIPTION OF THE COALFIELDFor the purpose of this paper the term Southern Coalfield includes also the South-Western Coalfield which together comprise the following Coal Districts:IllawarraDouglas ParkWollondilly-NattaiMoss Vale-Berrima (Hanlon, 1953).Geographically the coalfield is contained by the Illawarra Range in the east, the Shoalhaven River to the south, the Wollondilly River to the west, and in the north by a line...

Jan 1, 1958

By Frank E. Woolley, Robert D. Pehlke

Jan 1, 1965

By Cawte D. C, Just G. D, Whitchurch K. D

The stringent marketing specifications included in coal contracts mean that coal producers must supply cleaner and more consistent coal than may have been formerly required. Geostatistics has the potential to aid in the accurate estimation of the washability characteristics of coal. A prediction method, the Kriged Service Variable Approach has been developed.A Computer Aided Drafting and Design system has proved useful in the development and application of the approach. The geostatistical approach has been tested against coal geological and borehole data and applications discussed.

Jan 1, 1987

My selection of the Australian coal industry as the theme of this Presidential Address arose from the fact that it is one of our most important mineral industries. The industry is presently prospering.M.ore coal, mostly of better quality (except for certarn power-house types), is being produced more cheaply in terms of real money than at any time in the past, and exports overseas are currently at a highlevel.In. spite of this, concern has been expressed in certam quarters about the future of some phases of the industry; for example, there has been some public comment on the selling price of our coking coal to Japan, the possible over-export of our coking coals from New South Wales, the introduction of foreign capital to develop large-scale mining ventures in Queensland, and the proposed export of substantial quantities of coking coal from the same State.Furthermore, proposals for the introduction of atomic power plants into several States well endowed with reserves of coal have given rise to comment, and recently the Department of National Development(1968) warned that insufficient attention is being paid to "orderly development and careful husbanding of the nation's coal.To reach a balanced judgment on whether these views are well founded it is essential to make a broad survey of the present position of the coal industry in the Australian economy. I therefore propose to deal briefly with several aspects, and to comment, in particular, on the important subjects of exploration and research in progress at present on Australian coals.Detailed descriptions of the Australian coalfields are to be found in existing technical publications (e.g.. Andrew, 1965; McLeod, 1965) and the data on coal reserves have been progressively revised as more accurate information has become available. In New South Wales detailed knowledge of the coal reserVes is limited to under 20 per cent of the sur...

Jan 1, 1969

By Masaki Kitazume

Deep mixing method, in-situ admixture stabilization technique, has been developed and adopted for on land and marine construction works in Japan. The geotechnical design procedure of the method has been standardized in Ministry of Land, Infrastructure and Transport Government of Japan for port and harbor facilities, which includes the block type and wall type improved grounds for foundation stability, settlement reduction purpose. This procedure is based on the allowable stress concept, in which the induced stresses within the improved ground are confirmed to be lower than the allowable strength in the internal stability calculation. This procedure has been cited by several organizations to establish their standards. The Ministry has a plan to introduce a reliability based design for marine construction works in 2006, in which the design procedure on DM improved ground will also be modified to the reliability based. In the new design procedure, the average and variation of soil parameters and external loads are incorporated by partial safety factors to investigate the stability of improved ground. According to the plan, the author has been studied the design procedure and the magnitude of partial safety factors, and has established a preliminary draft of the standard. This draft will be brushed up through comparing the current design procedure. In this article, the design concept and design procedure of the method are briefly described.

Jan 1, 2004

By J. M. N. P. C. Teles, Venda Oliveira P. J., Correia A. A. S.

"AbstractA laboratory work was performed to study the mechanical behavior of a Portuguese soft soil chemically stabilized with binders and reinforced with metallic fibers when subjected to tensile stresses. To this end and in order to compare the tensile strength results done by two different tests, there were conducted two types of experimental tests: Tensile Split Strength Tests (TS) and Direct Tensile Strength Tests (T). The samples tested had the same binder quantity and different fiber contents, which allowed the characterization of the tensile behavior of the stabilized and reinforced soil, as well as the definition of the best fiber content. Results show that the binder is the main parameter controlling the behavior of the stabilized and reinforced soil until failure, while the influence of the fibers is noticed mainly at the post-failure behavior. The comparison between the tensile strength done by T and TS tests shows that the tensile split test can be used to estimate the tensile strength, although its results are lower than those obtained by the direct tensile tests in general.IntroductionDue to its poor mechanical characteristics, the construction on soft soils presents difficulties that require the use of soil improvement techniques such as chemical stabilization. However, even when mixed with binders, the tensile strength of the stabilized soil is poor, requiring, in certain cases, the use of expensive steel reinforcement or metallic beams, with obvious impact on the final cost of the work. Thus, for the cases where the tensile strength is a design requirement, the soil stabilization should be design with another element, whose primary role is to give tensile strength to the improved soil (Teles 2013).To fill the lack of published studies focused on soft soils both chemically stabilized and reinforced with metallic fibers, the present research aims to analyze the behavior of the improved soil when subjected to tensile stresses. To support the research there were conducted direct tensile tests (T) to directly measure the tensile strength of the samples and tensile split tests (TS) or Brazilian tests to obtain it indirectly. The samples tested had the same binder quantity but five different fiber contents in order to study the influence of the fibers in the improved soil behavior. In addition, a comparison between the results of both tests was made."

Jan 1, 2014

By Turgut Yalcin

"Recent years have seen a resurgence of interest in flotation cell design, and one of the areas where attention is being focused is flotation in centrifugal fields which aims at increasing the flotation rates by forced bubble-particle contact.A new cycloflotation device was developed at Laurentian University and tested on the nickel ore of Falconbridge Limited in Sudbury. In comparison with conventional flotation, cycloflotation yielded at least seven times faster flotation rates in terms of the mass of solids floated per unit time per unit flotation volume, while producing concentrate grades similar to those of conventional flotation. These results, which were obtained with a bench-scale ""cyclofloat cell,"" suggest that cycloflotation has the potential of setting a new direction in flotation technology.IntroductionFroth flotation is no doubt the dominant separation technique in the mineral processing industry. Since its inception early in this century, much research effort has been and is still being expended on this process. Until recent years, emphasis seems to have been placed on the chemical aspects of flotation, but there is now an increased awareness for the need to improve flotation machine performance and more and more attention is being directed towards this area. In a 1982 article on ""Flotation Machines"" (Young 1982) it is stated that "" ... by now the design of the machines used would have reached a high level of perfection, ... In fact, this is not the case ... "".The process of flotation in a flotation device may be considered to take place in several distinct stages as follows:"

Jan 1, 1994

By James F. Neill, O&apos

Brown iron ore resources in Barbour, Butler, Crenshaw, and Pike Counties were investigated in a drilling program and geological study by the Federal Bureau of Mines in cooperation with the Alabama Geological Survey and the University of Alabama. The aggregate footage drilled was 18,010 linear feet. When developed, reserves of 12,664,000 long tons of crude ore were indicated, containing from 26.9 to 29.0 percent iron and 0.2 to 1.6 percent manganese under a maximum overburden of 40 feet. Total inferred crude ore for the four counties was calculated to be 827,700,000 long tons. Beneficiation of samples by simulated log washing and use of a 118-inch screen yielded from 46.8 to 51.7 percent iron and 0.2 to 2.6 percent manganese. Screen-test studies indicated no appreciable interlocking between the iron and manganese minerals and the waste particles of materials retained on a 200-mesh screen. Clay was prominent in micron-size slimes. Silica was deleterious in the minus 20-mesh size. While an indicated 2,198,000 dry long tons of usable iron ore can be recovered, sink-and-float tests show that it may be possible for 4,654,000 dry long tons to be recovered by other than log washing. However, applicable commercial processes have not been demonstrated.

Jan 1, 1965

By M. A. Trevits, G. L. Finfinger

Various methods have been developed through US Bureau of Mines research to remove gas in advance of, during, and subsequent to mining. These include drilling horizontal or cross-measure boreholes from a mine opening, and vertical boreholes stimulated for drainage in advance of mining or for gob gas drainage. Techniques and equipment now exist that allow drilling a borehole at any angle to the vertical, and even along an arc. Stimulation treatments have also been developed that provide for increased gas production capability. This paper describes the long-term production history of five select gas drainage installations. The Bureau of Mines conducted or participated in four studies. The remaining study was conducted by the Equitable Gas Co. Principles of storage, release, and migration of coal bed gases The amount of gas contained within any given area of a coalbed depends on the coal's inherent storage capacity and the physical conditions of the coalbed. The gas storage capacity of coal is primarily a function of rank. As such, it cannot be affected by the presence of drainage holes (Kim, 1977). Certain physical conditions of the coalbed can, however, be changed that will affect the release and migration of gas. By pumping water out of the coalbed through the vertical boreholes, two important changes occur - pressure is reduced and water saturation is lowered. Reducing reservoir pressure releases gas as the coalbed adjusts and equilibrates gas to the change. Increasingly large amounts of gas are released for each incremental decrease in pressure. Lowering the water saturation level raises the permeability of the coalbed to gas and allows the gas to more readily migrate to the wellbore (Kisse and Edwards, 1975). For horizontal boreholes completed near mine openings, the coalbed has already undergone a pressure or water saturation reduction phase. This condition thus allows such boreholes to be highly productive with minimal water production. Case studies of coalbed gas production Pittsburgh Coalbed - Marianna mine 58 A methane drainage study was begun in July 1978 at Bethlehem Mines Corp.'s Marianna mine 58, Marianna, PA (Fig. 1). The work was conducted in a section of the mine that was advanced 1.5 km

Jan 8, 1986

The mineralogy and microstructure of mattes from the nickel flash smelter at Kalgoorlie, Western Australia, have been studied. The flash furnace matte consisted mainly of an intimate mixture of pentlandite and heazlewoodite with some nickel metal. The electric furnace matte was mainly an iron-nickel alloy with subsidiary pentlandite while the converter matte consisted mainly of heazlewoodite with crystals of nickel metal.

Jan 1, 1977