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By J. C. van Dyk

In a previous study by Van Dyk, et al., (2006) and Van Dyk et al. (2006), a FactSage model was developed to understand the chemistry and interpret mineral matter transformation during a fixed bed counter-current gasification process. It was concluded that the FactSage model developed, compared with HT-XRD experimental results and that the FactSage thermodynamic modeling sup-plies insight into specific mineral reactions and slag formation. The specific value for Sasol in using FactSage, in combination with HT-XRD is that it can be used to analyze equilibrium conditions for reactions occurring between inorganic and organic materials together, as well as to provide insight into mineral transformation and slag formation. The purpose of the present study was to improve the current FactSage modeling approach, by combining specific zones in the gasification process. This can improve and speed-up the interpretation of mineral matter transformations and flow properties of reacted mineral matter in coal and assist in identifying and quantifying slag formation in the gasifier operation at temperatures not reflected by normal AFT analyses. The updated and improved FactSage model compared favorably with the original model as well as with HT-XRD results and thus will be able to supply results in a faster and more convenient manner. In the new FactSage model, supported by HT-XRD experimental findings, it is indicated that feldspar formation (including anorthite) correlated with slag formation at temperatures around 1000°C and no slag formation in the base case coal was observed in the drying and devolitilization zone, as was to be expected. Feldspar is one is the mineral species which has the lowest AFT causing the most slag-liquid formation and forms probably as a product between the SiO2, Al2O3 and Ca-containing species. In the gasification zone it was clear that slag-liquid formed at a temperature of 1000°C, with a decrease in the feldspar content. Mullite formation was also observed in the base case sample in the temperature range 1000°C and 1100°C. The decrease in the amount of SiO2 at 1100°C is related to the formation of mullite, but also that the slag-liquid phase also contains an amount of SiO2 in the molten form.

Jan 1, 2014

By R Cannings, J Wallace, M McCamley

The mining industry continues to have major disasters (Bingham Canyon, Pike River, Upper Big Branch, Mount Polley and Samarco), which often have a devastating effect on the enterprise, in terms of personnel deaths and injuries, environmental destruction, and financial and reputational loss. These disasters are not imposed from outside the business or organisation, they are almost always a function of loss of control of the management of the organisation’s critical assets and processes that they contain or to which they are exposed.Asset integrity is discussed as an effective response to business risks in order to mitigate, control and recover from loss scenarios that could expose a mining operation to significant property damage and business interruption, or even total loss. Vital to this process is the identification and control of risks to critical assets. Components of a critical asset assurance program are presented for discussion.Formal risk assessment has a longer history in industries other than mining, eg petrochemical, nuclear, military, aviation and space industries. Risk assessment is a structured, proactive approach to understanding and improving risks, as opposed to a reactive ‘fix-it-when-it-breaks’ mentality. Risk assessment techniques were triggered by major public disasters, such as the Flixborough chemical plant disaster (1973), Three Mile Island nuclear plant event (1979) and others.Today, most industries see risk assessment as an inherent part of their business, but do mining sites capture business risks that are related to major loss scenarios, which could have a significant impact on the operation?Does your risk assessment process:- involve a team having the right skill set so that the discussion is both stimulated and technically sound?- use generic assessment when a site-specific assessment is needed?- fail to consider all possible outcomes, including maximum foreseeable loss (MFL)?- fail to identify all hazards and controls associated with a particular activity?- fail to monitor controls effectively?This paper addresses the issues identified by these questions and provides some direction for developing a risk management process where business risk associated with critical asset integrity is integrated with other business and safety and health risk processes to provide a robust method for managing your business. Case studies and common findings from critical asset failures are used to support the need to include critical asset assessments as part of business risk management processes.CITATION:Wallace, J, McCamley, M and Cannings, R, 2016. How robust are your asset integrity management processes? In Proceedings International Mine Management Conference, pp 53-64 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 22, 2016

By T. G. Sitharam, Resmi Sebastian

"Wave propagation studies across jointed rocks have significance in the fields of rock mechanics and geophysics. The passage of a seismic wave induces strains in rocks and often, these strains are of low magnitudes except at the vicinity of source. These low magnitude strains are generally in the elastic range and hence elastic constants necessary for the design and analysis of strength of rock mass, can be derived from wave velocities. Measurement of travel time velocities and measurement of resonance frequencies are the two methods usually adopted for obtaining wave propagation velocities.Resonant column apparatus measures wave velocities from the resonant frequencies obtained during testing. Depending on the type vibration applied, torsional or flexural, shear and compression wave velocities are secured. By varying the amplitude of vibrations applied, various strain levels can be introduced and corresponding resonant frequencies and wave velocities can be calculated. The resonant column experiments were performed on a model material, hardened Plaster of Paris (POP) samples, in laboratory. The paper explains the preparation of samples and the working mechanism of resonant column apparatus along with the estimation of wave velocity from resonant frequency. The numerical simulation of resonant column apparatus using distinct element method and its validation with the experimental results are presented in the paper.A distinct element code is usually used to simulate the movement of materials with intersecting discontinuities. Finite rotations and displacements of individual blocks representing the material are permitted and new contacts between the blocks are identified as the calculation progresses. Three dimensional Distinct Element Code (3DEC), the software intended for the numerical simulation of rock engineering projects, can well simulate the behavior of jointed rocks under static and dynamic loading conditions. The numerical simulation of resonant column apparatus has been performed with 3DEC considering its efficiency in modeling jointed rocks.The numerical modeling of the resonant column apparatus with application of torsional and flexural vibrations to the sample is elaborated in the paper. The response of samples to a range of frequencies is obtained and the frequency that induces maximum displacement in the sample is measured as the resonant frequency, for any particular strain level. The displacements measured at various points of the sample during application of vibrations are compared and presented. The numerical modeling of resonant column apparatus with an intact sample (without joint) and a sample with a joint incorporated are explained at a particular strain level. The resonant frequencies obtained from laboratory experiments and numerical simulations are compared and illustrated. It has been found that resonant frequencies obtained using numerical and laboratory experiments are in good comparison and can be extended for various strain levels and sample conditions."

Jan 1, 2015

By T. Motegi

Semisolid casting provides grain refinement of the cast structure and prevents macro-segregation. The conventional semisolid slurry is obtained by electromagnetic or mechanical stirring. In our process, the magnesium alloy (AZ31) slurry is made using an inclined cooling plate instead of the conventional methods. The slurry obtained is cast into a twin-roll caster and makes a continuous sheet of 2 or 3 mm thick. The most important factors that influence the sheet casting are the casting temperature and twin-roll speed.

Jan 1, 2007

By Charles E. Munroe

At the outset of the war the uncontrolled production and possession of explosives obviously became a serious menace to the safety of persons and property and the successful conduct of military opera- tions. Even in the years immediately preceding the entrance of the United States into the Great War explosives were employed in attempts to wreck munitions plants as at Eddystone, Pa., or to inter- rupt transportation and conveyance by demolition of munition-laden cars as at Black Tom Island, N. Y., or by attacks on ships, bridges, and viaducts. Outrages with explosives, such as that which Holt inflicted on the Senate reception room, United States Capitol, were not infrequent, and often caused serious loss of life and injury to persons as well as destruction of property. The regular manufacturers of explosives were keenly alive to this menace and early took such steps as lay within their power to meet it as is shown by the following letter:

Jan 1, 1921

By Burt C. Mariacher

The Minerals Beneficiation Division meets each year at the Annual Meeting of AIME. All members are invited and encouraged to attend. For the information of those who did not attend the meeting in Denver last February, this column presents a summary of the reports given and topics discussed. Technical Committee Coordination Consolidation of technical programs having common interest to MBD and the Extractive Metallurgy Division is proving a considerable success, both on the technical committee level-through the efforts of the MBD-EMD Coordinating Committee-and in special symposia. MBD Chairman, R. S. Shoemaker, noted that J. D. Prater will be serving as Chairman of both the MBD Chemical Processing Committee and the EMD Hydrometallurgy Committee for 1970-71. R. P. Ehrlich commented on the cooperative effort of both divisions in organizing the Copper Metallurgy Symposium held at the Denver Meeting. This effort, he said, was important to the success of the Symposium. H. R. Spedden discussed inter-Division coordination activities on the SME level. The forthcoming MBD-M&E-EMD Joint Lead-Zinc Symposium is yet another example of progress in this direction.

Jan 1, 1970

By Frank Alfred Fahrenwald

A complete list of the elements as given for 1915 includes 18 that melt above 1,700" C. There does not exist one complete thermal equilibrium diagram for any pair of these 18 elements. Several of these elements have been combined, in relatively small proportions, with metals of lower melting point: e.g., tungsten, molybdenum, and vanadium, in steels, or with nickel and cobalt; but of this refractory group, platinum is the only one that has been extensively studied in this connection. When one considers that, with few exceptions, the industries have made use of alloys to the exclusion of pure metals, it is reasonable to expect that alloys of this refractory group will invade fields in which the pure metals have found little application. The past neglect of this class of metals has, no doubt, been partly due to the rarity of some of them, for even though alloys of very valuable properties should be developed, their cost, unless in exceptional applications, would be prohibitive. There is also a well-founded reluctance to undertake research involving very high temperatures which, in the case of most of these elements, must be accompanied by an inert atmosphere as well. This combination of high temperatures*and control of atmosphere within the heating chamber of any furnace of present design is a difficult problem. It is the purpose of this paper to give results,' of an investigation of one binary series of this group, in which methods were employed that avoided the usual difficulties accompanying high-temperature alloy investigation. , Historical.—The alloys of tungsten and molybdenum have received very little consideration during the past. A review of available literature reveals very little regarding this system, and that which has been recorded seems to be at fault. Mennicke2 writes, "Die bekannteste Verbindung

Jan 1, 1917

By John R. Benham

The Blue Joint Mtn. RARE II area may contain barite resources. One claim, the Woods Creek Barite No. 1, contains two veins of barite of drilling mud quality. The quantity of barite present could not be determined due to limited surface exposures. Sections 1, 2, 11 and 12 of T. 2 S., R. 23 W. in the study area are classified by the U.S. Geological Survey as prospectively valuable for geothermal energy resources. These sections border Blue Joint Creek Hot Springs, which are outside the study area.

Jan 1, 1981

By Michael D. Fenton

The modest mineral industry of Afghanistan continued to suffer adversely from internal disorders that were essentially the result of the continued presence of elements of the armed forces of the U.S.S.R. Despite press reports near yearend intimating that the Soviets might reduce troop strength in Afghanistan, there were no indications of any significant numeric reductions. Indeed, there were clear demonstrations of heightened military actions along the Afghani-Pakistani border, including bombing raids on settlement sites for Afghanis within the territorial limits of Pakistan, actions hardly demonstrative of conditions indicative of Soviet withdrawal.

Jan 1, 1988

By Bingguo Liu, PENG LIU, Haigang Dong, Jinhui Peng, Libo Zhang

Parameters of technique to decarburize from spent petrochemical catalysts via microwave oxidation roasting were investigated. Decarburization process was performed on a microwave heating system. The results showed that the decarburization percentage of spent petrochemical catalysts was significantly affected by roasting temperature and sample thickness in the range studied. The decarburization percentage was 99.5% in microwave fields under the optimized conditions, roasting temperature 600 °C, roasting time 40 min and sample thickness 2 cm respectively. The residuum after microwave decarburization was characterized by field emission scanning electron microscopy (FE-SEM) which showed that the deposit carbon had been removed effectively.

Mar 1, 2017

DAVID THOMAS 1871 R. W. RAYMOND 1872-1874 A. L. HOLLEY 1875 ABRAM S. HEWITT 1876 T. STERRY HUNT 1877 ECKLEY B. COXE 1878-1879 WILLIAM P. SHINN 1880 WILLIAM METCALF 1881 RICHARD P. ROTHWELL 1852 ROBERT W. HUNT 1883 JAMES C. BAYLES 1884-1855 ROBERT H. RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B. POTTER 1888 RICHARD PEARCE 1889 ABRAM S. HEWITT 1890 JOHN BIRKINBINE 1891-1892 H. D4. HOWE 1893 JOHN FRITZ 1894 J. D. WEEKS 1895 E. O. SPILSBURY 1896 THOMAS M. DROWN 1897 CHARLES KIRCHHOFF 1898

Jan 1, 1944

PRESIDENTS DAVID THOMAS 1871 R W RAYMOND 1872-1874 A L HOLLEY1875 ABRAM S HEWITT 1876 T STERRY HUNT 1877 ECKLEY B COXE 1878 - 1879 WILLIAM P SHINN 1880 WILLIAM METCALF 1881 RICHARD P ROTHWELL 1882 ROBERY W HUNT 1883 JAMES C, BAYLES 1884-1885 ROBERT H RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B POTTER 1888 RICHARD PEARCE 1889 ADAM S HEWITT 1890 JOHN BIRKINBINE 1891-1892 H M HOWE 1893 JOHN FRITZ 1894 J D WEEKS 1895 E G SPILSBURY 1896 THOMAS M. DROWN 1897 CHARLES KIRCHHOFF 1898 JAMES DOUGLAS 1899-1900

Jan 1, 1952

DAVID THOMAS 1871 R. W. RAYMOND 1872-1874 A. L. HOLLEY 1875 ABRAM S. HEWITT 1876 T. STERRY HUNT 1877 ECKLEY B. COXE 1878-1879 WILLIAM P. SHINN 1880 WILLIAM METCALF 1881 RICHARD P. ROTHWELL 1852 ROBERT W. HUNT 1883 JAMES C. BAYLES 1884-1855 ROBERT H. RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B. POTTER 1888 RICHARD PEARCE 1889 ABRAM S. HEWITT 1890 JOHN BIRKINBINE 1891-1892 H. D4. HOWE 1893 JOHN FRITZ 1894 J. D. WEEKS 1895 E. O. SPILSBURY 1896 THOMAS M. DROWN 1897 CHARLES KIRCHHOFF 1898

Jan 1, 1943

PRESIDENTS DAVID THOMAS 1871 R W RAYMOND 1872-1874 A L HOLLEY1875 ABRAM S HEWITT 1876 T STERRY HUNT 1877 ECKLEY B COXE 1878 - 1879 WILLIAM P SHINN 1880 WILLIAM METCALF 1881 RICHARD P ROTHWELL 1882 ROBERY W HUNT 1883 JAMES C, BAYLES 1884-1885 ROBERT H RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B POTTER 1888 RICHARD PEARCE 1889 ADAM S HEWITT 1890 JOHN BIRKINBINE 1891-1892 H M HOWE 1893 JOHN FRITZ 1894 J D WEEKS 1895 E G SPILSBURY 1896 THOMAS M. DROWN 1897 CHARLES KIRCHHOFF 1898 JAMES DOUGLAS 1899-1900

Jan 1, 1952

PRESIDENTS DAVID THOMAS 1871 R W RAYMOND 1872-1874 A L HOLLEY1875 ABRAM S HEWITT 1876 T STERRY HUNT 1877 ECKLEY B COXE 1878 - 1879 WILLIAM P SHINN 1880 WILLIAM METCALF 1881 RICHARD P ROTHWELL 1882 ROBERY W HUNT 1883 JAMES C, BAYLES 1884-1885 ROBERT H RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B POTTER 1888 RICHARD PEARCE 1889 ADAM S HEWITT 1890 JOHN BIRKINBINE 1891-1892 H M HOWE 1893 JOHN FRITZ 1894 J D WEEKS 1895 E G SPILSBURY 1896 THOMAS M. DROWN 1897 CHARLES KIRCHHOFF 1898

Jan 1, 1937

DAVID THOMAS 1871 R. W. RAYMOND 1872-1874 A. L. HOLLEY 1875 ABRAM S. HEWITT 1876 T. STERRY HUNT 1877 ECKLEY B. COXE 1878-1879 WILLIAM P. SHINN 1880 WILLIAM METCALF 1881 RICHARD P. ROTHWELL 1852 ROBERT W. HUNT 1883 JAMES C. BAYLES 1884-1855 ROBERT H. RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B. POTTER 1888 RICHARD PEARCE 1889 ABRAM S. HEWITT 1890 JOHN BIRKINBINE 1891-1892 H. D4. HOWE 1893 JOHN FRITZ 1894 J. D. WEEKS 1895 E. O. SPILSBURY 1896 THOMAS M. DROWN 1897 CHARLES KIRCHHOFF 1898

Jan 1, 1942

IRON AND STEEL DIVISION Established as a Division February 22, 1928 K C. McCutcheon, Chairman T. L. Joseph, Past Chairman J B Austin, Vice-Chairman E K Miller, Vice-Chairman T. J. McLoughlm, Vice-Chairman Ernest Kirkendall, Secretary-Treasurer CO M M I T T E E S EXECUTIVE J. A. Bowers '54 J. S. Marsh '55 R. W. Campbell '54 D. L. McBride '53 Walter Carroll '55 G. B. McMeans '53 K. L Fetters '53 F. L. Toy '54 H. M. Griffith '55

Jan 1, 1952

DAVID THOMAS 1871 R. W. RAYMOND 1872-1874 A. L. HOLLEY 1875 ABRAM S. HEWITT 1876 T. STERRY HUNT 1877 ECKLEY B. COXE 1878-1879 WILLIAM P. SHINN 1880 WILLIAM METCALF 1881 RICHARD P. ROTHWELL 1852 ROBERT W. HUNT 1883 JAMES C. BAYLES 1884-1855 ROBERT H. RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B. POTTER 1888 RICHARD PEARCE 1889 ABRAM S. HEWITT 1890 JOHN BIRKINBINE 1891-1892 H. D4. HOWE 1893 JOHN FRITZ 1894 J. D. WEEKS 1895 E. O. SPILSBURY 1896 THOMAS M. DROWN 1897 CHARLES KIRCHHOFF 1898

Jan 1, 1941

PRESIDENTS DAVID THOMAS 1871 R W RAYMOND 1872-1874 A L HOLLEY1875 ABRAM S HEWITT 1876 T STERRY HUNT 1877 ECKLEY B COXE 1878 - 1879 WILLIAM P SHINN 1880 WILLIAM METCALF 1881 RICHARD P ROTHWELL 1882 ROBERY W HUNT 1883 JAMES C, BAYLES 1884-1885 ROBERT H RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B POTTER 1888 RICHARD PEARCE 1889 ADAM S HEWITT 1890 JOHN BIRKINBINE 1891-1892 H M HOWE 1893 JOHN FRITZ 1894 J D WEEKS 1895 E G SPILSBURY 1896 THOMAS M. DROWN 1897 CHARLES KIRCHHOFF 1898

Jan 1, 1938

By Priscilla Aki Mori de Hanashiro, Viviane Tavares de Moraes, Denise Crocce Romano Espinosa, Hugo Hashimoto

"The LCDs are used in televisions, calculators, mobile phones, computers (laptops and tablets), video games and other electronic devices. The advancements in technology make obsolete these devices, causing excessive disposal of LCDs and therefore decreasing life span of landfills. In this context, the LCDs from LED LCD TVs arise as an additional source of waste electrical and electronic equipment (WEEE). Thus, it is essential to develop LCDs recycling methods, beginning with the LCD characterization followed by displays processing, aiming the materials separation and using some Ore Treatment Techniques, and finally, the recovery of indium using acid leaching. The analysis methods that will be used in this work are: Fourier Transform Infrared (FT-IR) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES).IntroductionLiquid Crystal Display (LCD) technology is applied in modem televisions, calculators, mobile phones, computers and a wide range of electronic devices. It has replaced Cathode Ray Tube (CRT) technology as the most advantageous display product, due to lower electrical power consumption, size and weight reduction, and no radiation emission [ 1]. The constant improving of LCD screen technology reflects on its growing contribution to the amount of waste electrical and electronic equipment (WEEE): an estimated 50 million tons of WEEE are produced every year [2]. Once the most common method of its disposal are landfills, the LCD technology therefore became an environment issue [3].LCD structure is composed by components made by different materials. In order to develop a LCD recycling methodology that gives the right destination to these materials, a previous characterization stage is required. This characterization includes a disassembly process and material identification analysis. One of the LCD components is the screen, which is composed by polymeric and glass layers. The liquid crystal glass was the starting material of this study. It contains indium in the form of indium tin oxide (ITO) film. This ITO film is deposited in the glass by a sputtering process and acts as the electrode material [4,5]. It has in its composition 90% ofln203 and 10% ofSn02 [6]."

Jan 1, 2014