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The purpose of this paper is to cover in a general way the extent, geology, quality of product, working methods and trials of the coal mining industry. of New South Wales from 1946 to the present day, with particular reference to the Western field.It must be clearly understood that any opinions expressed are those of the author and not necessarily those of the Joint Coal Board.The extent of the Western coal field at the present stage of investigation may be said to be from a few miles east of Katoomha to a few miles north-west of the township of Ulan, the total distance being 150 miles.To the west of a line from the Western Highway from Lithgow through Wallerawang, PortIand, Tyldesley, Ben Bullen, Kandos and Rylstone, there are no signs of coal except for one or two outiiers in the neighbourhood of Portland. To the east of this line the coal-bearing areas extend to the seaboard approximately 80 miles to the east.GEOLOGY AND CHARACTERISTICS OF THE COAL SEAMSThe Western coal measures belong to the Upper or Newcastle series, which have been correlated with the Sciritheru or lllawarra, and the North-western or Gunnedah measures. Being close to the margin of the coal basin the Western measures have an average thickness of only 200 ft. to 500 ft., or approximately one-half of the maximum development of the Newcastle measures. They are underlain by Upper Marine beds which in turn rest directly on Devonian rocks.

Jan 1, 1954

By Berny Rivera

The paper point out the Galvanox process developed at the University of British to leach concentrates containing copper sulfide mixtures, mainly chalcopyrite. This patented process is based primarily on the galvanic interaction between chalcopyrite and pyrite, which allows chalcopyrite to be leached preferentially over pyrite. Under the correct process conditions, near-complete extraction of copper can be reached typically within twelve hours. This study will also show that this process is suitable to treat low grade copper concentrates (bulk concentrates) taking advantage of the selectively of chalcopyrite over pyrite, and the use of pyrite as a catalyst.

Sep 9, 2007

By F. N. Kissell, C. M. McCulloch, Maurice Deul, J. R. Levine

The methane content of virgin bituminous coalbed can now be measured accurately in the field with exploration core samples from vertical boreholes. The gas content of the coal per unit weight can be used either to design a mine ventilation system or to determine if degasification of the coalbed will be necessary before mining, and to determine the gas resources in the coalbed. The equipment necessary to conduct the test costs less than $50. The gas content of the coal in place in the ground is determined by summing the gas lost from coring, gas measured during desorption, and the residual gas in the coal. Upon removal from the borehole, the core sample is placed in an airtight container and desorbed for several weeks until the desorption rate is below 0.05 cm3/g for 5 consecutive days. The gas lost from the core while it was being cored and the residual gas are estimated by a new graphical method. The amount of gas remaining depends upon whether the coal is friable or blocky. Friability appears to relate to the depth of the sample below the surface, fixed carbon percentage, Hardgrove grindability index, and proximity to tectonic disturbance. Friable coals emit nearly 96 pct of the total gas during desorption whereas a blocky coal emits only 60 pct of its total gas. Coalbeds that are ill defined as to their blocky or friable nature must be tested in the laboratory for unambiguous analysis.

Jan 1, 1975

By Rosana Vilarim da Silva

O objetivo deste trabalho foi desenvolver um compósito permeável formado por uma matriz de polipropileno reforçada com resíduos de construção e demolição (RCD). Inicialmente foi feita a limpeza, peneiramento e caracterização do RCD. O compósito foi conformado na forma de placas pelo processo de compressão a quente. O RCD foi misturado com os grânulos do polímero e a mistura disposta em um molde que foi fechado e comprimido com carga de 1 ton e mantido na temperatura de 210oC por 10 min. Foram conformadas placas permeáveis e impermeáveis variando-se o percentual dos constituintes e granulometria do RCD. Para a caracterização foram realizados ensaios de permeabilidade e flexão em três pontos. As placas permeáveis apresentaram elevado grau de permeabilidade, muito superior aos requisitos mínimos para concreto. Foi constatado que a distribuição granulométrica tem influência na resistência mecânica e permeabilidade do compósito. O aumento do teor de granulados finos promoveu aumento nas propriedades mecânicas em flexão sem perda da permeabilidade. Com a impermeabilização das placas e consequente redução de vazios as propriedades mecânicas em flexão praticamente triplicaram. Analisando os resultados de uma forma geral pode-se concluir que há margem para melhorar o desempenho mecânico do compósito sem perda da permeabilidade.

Oct 30, 2017

By C. J. Van Treeck

PGE concentrations of 18 g/t occur in the pyroxene rich rocks at the Union Bay Alaskantype complex. This PGE enrichment is hosted in magnetite veins. These veins cross magmatic layering and have an irregular morphology in both outcrop and thin section. Fe-Ti oxide geothermometry suggests that this mineralization took place between ~700-400°C. A variation in the amount of ilmenite and Mg- Al spinel exsolution in magnetite correlates with temperature estimates, lower temperature magnetite has less exsolution. Hydrous silicates form an alteration envelope around magnetite veins with a formation temperature of <575oC, vary with temperature, and contain appreciable amounts of Cl. Interaction of a PGE-Fe-Cl rich fluid with clinopyroxene increased the fluids pH and decreased PGE and Fe solubility depositing a PGE enriched magnetite within the Pyroxenites and Olivine Pyroxenites of the Union Bay complex.

May 1, 2003

THOUGH the literature on the chamber process is considerable, it mostly refers to European conditions. Owing to the demand for acid for flotation and leaching at the mine, it may be necessary to work the process under other conditions. Consequently, some results obtained during the chlorination days at Mount Morgan, within the Tropic of Capricorn, may be useful for reference when working in a similar climate. Though the chambers must be protected against tropical storms, thorough ventilation should be provided, with plenty of space between the chambers, which are almost invariably crowded together. Not only does the space assist in the cooling of the chambers, but it is very desirable during repairs, when lead andtimber have to be hoisted up. The connecting flues between the chambers, which are fairly efficient mixers and condensers, should be round, supported from above, and with the least possible timber about them. Their position and arrangement deserve careful attention. Lattice work will be sufficient protection for the sides of the chambers, and the roof should be high and well ventilated. The Mount Morgan plant, crowded and not well situated, consisted of seven chambers (four over 50 ft. in length), one Glover tower 7 ft. 2 in sq. x 20 ft. high, one Gay Lussac 9 ft. sq. x 30 ft. higb, also one 5 ft. diam. x 25 ft. high. There was one pipe column 4: ft. sq. x 14 ft. 6 in. high. The chambers were run as one unit, and were much lower than those usually constructed in Europe-less than 15 ft. high. Provided that suitable timber can be obtained, 20 ft. is quite low enough. It should be quite satisfactory to use round poles for the studs, and so admit more air space between studs andlead.

Jan 1, 1920

By V. F. Petrov, O. D. Khmelnitskaya, V. M. Lodeischikov

"The processing of copper gold ores is one of the major issues of gold-mining industry in the beginning of 21st century. In this case, application of ammoniacal cyanidation process for this type of mineral raw materials deserves special attention. Irgiredmet Institute has carried out a wide range of studies on ammoniacal cyanidation process and evaluated the possible commercial use of this process for Russian operating plants. Copper gold-bearing ore from a current Russian deposit was studied. The content of gold and copper in the ore is 9.4 g/t and 0.4%, respectively. Based on the results of preliminary test work, a flow sheet was developed. It included gravity concentration followed by cyanidation of the gravity tailings using CIP. The flow sheet provides sufficient total gold recovery (91.5%). However, this technology has disadvantages, such as high specific consumption of reagents: 4.5 kg/t NaCN and 13.5 kg/t Ca(OCl)2 the ore and the increased gold grade in the liquid phase of the tails slurry (0.2 g/t). In order to improve cyanidation process parameters, test work on gravity tails processing using ammoniacal cyanidation was carried out. After the test work was completed, ammoniacal cyanidation flow sheet for copper gold-bearing ores was developed. Leaching conditions were optimized using recycled process solutions. Recommendations on gold recovery from the solutions and tails detoxification are given. The proposed flow sheet provides 91.5% gold recovery. In this case, compared to the conventional option, the consumption of cyanide decreases by 3-4 times.INTRODUCTION The technology of precious metals recovery from gold-bearing ores is based on cyanidation. This accounts for up to 90% gold recovery and the significant portion of silver (Lodeischikov, 1999). However, there exists the category of so called refractory ores. They are not amenable to direct cyanidation (without using additional expensive processes), or they are characterized by low indices of metals recovery and high consumption of reagents. The latter also include copper gold ores. Their deposits can be found extensively both worldwide and in Russian Federation. A feature of these ores is that they contain not only gold but also copper. It is considered not only as a valuable component but also as a harmful mineral impurity that hinders gold cyanidation, gold precipitation from the solutions by cementation onto zinc dust and adsorption onto activated carbon (CIL, CIP-processes), detoxification of cyanide bearing effluents."

Jan 1, 2018

By Carlos Soria

El presente texto describe los Sistemas de Gerencia de la Información y su aplicación en la industria minera con el objetivo de optimizar la gestión total de la empresa. Dichos sistemas manejan información del proceso y sus valores de producción, cálculos, consumos de energia, emisiones de plantas, tiempos de funcionamiento de equipos, eventos, alarmas, mediciones de laboratorio y control estadístico, etc. De forma que dicha información pueda ser reunida y consolidada, convirtiéndose en materia de significado y relevancia disponible en base a análisis, reportes, listas, tendencias y gráficos para que el usuario final de una planta o en sus oficina pueda tomar mejores decisiones.

Jul 17, 2000

This paper investigates the effects of solids concentration and the addition of Dispersant S40 on the flowability of original and ground limestone slurries. A rotational viscometer with a concentric cylinder geometry and a controlled-stress rheometer with a cone-and-plate geometry were used to characterize the rheological behaviors of limestone slurries. The rheological behavior of original limestone slurries (<100 µm) is transformed through different types of flows with increasing solids concentration. The use of Dispersant S40 can improve the slurry flowability by decreasing viscosity and eliminating Casson yield stress. It is therefore used as a grinding aid for the wet ultrafine grinding of limestone. The rheological behaviors of ground limestone slurries vary with grinding from a starting dilatant flow-ability to a resulting pseudoplastic one with an evident Casson yield stress in combination with a thixotropic character. The appearance of pseudoplastic flowability combining thixotropy is related to the fineness of a ground product and its specific surface area, which are both correlated to solids concentration and the additive amount of Dispersant S40. In addition, the accurate rheological characterization of time-dependent fluids is dependent on the instruments used and operation conditions.

Jan 1, 2007

By Gordon B. French, Donald E. Garrett

INTRODUCTION Crude oil reserves in the United States are still very large, even though for many years they have not been sufficient to supply our entire domestic requirements. They are continuously being depleted as oil is pumped from the ground, but new discoveries and improved secondary and tertiary recovery methods are helping to reduce the rate of depletion. It is thus a slowly diminishing resource, but even as it is being consumed, immense reserves of oil are left behind as the so called "un-recoverable" portion of petroleum formations. Most oil fields can only obtain a 15 to 40% recovery of the original reservoir, and it is widely quoted that there are still about 300 billion barrels of this un-recoverable oil still in place (Mauch, 1980, etc.). With the present comparatively high oil prices, and the possibility of even higher future prices and short supply, this oil becomes an interesting potential reserve. Mining the petroleum formation would be one means of recovering at least a portion of this oil. The concept of oil mining is neither new nor limited to conventional oil fields, since the procedure could be equally employed with the otherwise difficult to produce heavy oil deposits, and the solid or semi-solid tar sands and diatomaceous hydrocarbon formations. Estimates place the U.S. tar sand resource at about 30 billion barrels, and heavy oil at 5-10 billion barrels (Unitar, 1982). Figure 1 graphically summarizes the heavy oil reserves based upon formation depth and characteristics, while Figure 2 shows their location. It is apparent that the preponderance of reserves are in California and Texas, but that they also occur in many other states. The major companies engaged in oil recovery from the heavy

Jan 1, 1983

By D. J. Dollhopf

An overburden handling dragline operation was conducted at a strip mine near Colstrip, Montana. The objective of the demonstration was to determine the degree a dragline could mix overburden inhibitory zones during the spoiling process. In order to quantify the mixing process the overburden was: 1) scatter spoiled; 2) dump spoiled; and 3) spoiled in a normal manner. This demonstration was part of an effort to investigate means of reestablishing non-polluted hydrological systems in areas where surface mining directly impacts shallow ground-water resources. When inhibitory material constituted < 5% of the total overburden volume, such material was essentially not detectable in the resultant spoil pile. When inhibitory material exceeded 15% of the overburden volume it was always found in the resultant spoil pile, generally with a smaller extent, indicating partial dilution. Inhibitory overburden zones often reappeared at the base or top of spoil piles in the potential aquifer and root zones suggesting the need for selective placement procedures. Scatter spoiling did not appear to be significantly more effective than normal spoiling, however clump spoiling seemed to produce less mixing of inimical zones. Mining activity has reduced ground-water levels within 1600 m of the active pit. The aquifer which is developing in spoils appears to have similar confinement characteristics as those that existed in the premined aquifer. To date no definite trends have been observed concerning changes in surface or ground-water chemistry associated with mining.

Jan 1, 1978

By L. Harris

The Yanacocha project is the first foreign investment in Peruvian mining since Cuajone during 1976. Three years after the project began, it has become the largest producer of gold from heap-leach operations in the world and the top producer in Latin America. The success of Minera Yanacocha SA (MYSA) opens a new chapter in Peruvian mining with the exploitation of its widely spread gold deposits. And it has attracted the interest of foreign investors in Peru’s mineral resources. Construction began on Aug. 1, 1992. The first gold bar was poured on Aug. 7, 1993 from ore from the Carachugo Mine. During 1993, Minera Yanacocha produced 2.5 t (81,000 oz) of gold and 9.4 t (304,000 oz) during1994 (40% above budget). Production was expected to exceed 15.5 t (500,000oz) during 1995 with the start-up the Maqui Maqui Mine.

Jan 1, 1996

By Bengt H. Fellenius

Session 2, Deep Foundation without Soil Excavation, has attracted no fewer than 22 papers dealing with subjects from soil improvement by grouting, injection, and deep mixing techniques through vibroflotation and special piles, including aspects pertaining to conventional driven and bored piles. In the short time available, it is not possible to both do justice to the papers and provide a critical review of the state-of-the-art. Instead, to meet the objective of making the next half hour worthwhile to the audience, I have chosen to comment on a few special points brought forward in the papers and thereafter to discuss more in detail a couple of aspects I have deemed to be of general interest. Four papers deal with jet-grouting, injection, and deep mixing techniques: DOMSKI, J. J. Reinforcement of subsoil under the foundations of historical buildings in Cracow using deep injection technique. RESTELLI, A. B, BERTERO, M., and LODIGIANI, E. Deep mixing technology to improve the bearing capacity of a very soft clayey soil under an earth embankment.

Jan 1, 1994

By Yuanwci Shi

This paper discusses the results of research on the interaction between roof strata and shield supports including the active and passive supporting functions of the shield supports which prevents roof strata separation; pressure distribution on the canopy and under the base plate as measured in the laboratory and underground; comparison between various shield structures regarding their effectiveness on roof and floor control; and determination of optimum support capacity under given geological and mining conditions including hard-tocave roof

Jan 1, 1997

By Regina Paula Garcia Santos

Inconel 625 é utilizado na indústria petrolífera em sistemas de bombeamento onde pode ocorrer movimento relativo na presença de partículas abrasivas, mas devido ao seu elevado custo este pode ser depositado em substratos mais baratos tornando-se uma alternativa viável. A deposição pelo processo PTA permite altas taxas de deposição e baixa diluição. Realizou-se a parametrização do processo PTA para obter depósitos espessos em único passe (> 3 mm) de Inconel 625 sobre aço ABNT 1045. Corrente, velocidade de soldagem e taxa de alimentação foram variados. Análises macrográficas permitiram a medição das características geométricas dos cordões. Foram identificadas duas famílias, uma com uma diluição menor (

Aug 16, 2017

By M. Karmis

Surface subsidence is an inevitable consequence of many underground mining operations and has been recognized as such since the fifteenth century. Damage resulting from this phenomenon ranges from simple land settlement to severe structural damage to buildings and has been witnessed in rural (Illinois, Colorado, West Virginia, Virginia, Pennsylvania) as well as in urban areas (Pennsylvania, West Virginia, Illinois, Wyoming). In fact, it is estimated that over 2 million acres of land across the United States have been affected by mining subsidence, of which 140,000 acres are in urban areas (Singh, 1978; Johnson and Miller, 1979). Further, it is estimated that during the next twenty years an additional 1.5 to 2.4 million acres of land will also be affected by mining. Subsidence prevention is not feasible, at least under the existing technologic and economic constraints of underground coal mining. Foreign experience has demonstrated, however, that subsidence can be successfully controlled if an accurate method of predicting ground movements is available. Such techniques have been developed in many coalfields, where it is currently accepted that subsidence can be predicted within ± 20 percent of the actual values. Furthermore, such movements can be translated into anticipated structural failures using established damage criteria, thus enabling appropriate precautionary measures to be implemented.

Jan 1, 1983

By G. K. Derby

The Bureau of Mines investigated methods for removing dragline bucket wire rope terminations with the objective of finding efficient methods that are safer than the method most commonly used at U.S. surface mines, which is to use the explosive impact of a projectile fired from a cannon to remove the rope termination. Removal of a wire rope termination for repair or replacement requires separation of the wedge and socket that lock together to secure the rope end. The Bureau investigated currently used methods and improved upon and tested two safer alternate methods for removing wire rope terminations. A cannon test program was conducted, using 40-and 50-gr primer (detonating) cord, to establish the possible force produced with a 4-in-bore cannon and a 55-lb projectile. Wedge and socket units supplied from cooperating mines were separated under controlled conditions to establish data on separation force requirements. The two alternate methods investigated were use of the force generated by (1) a pendulum ram and by (2) a portable hydraulic pusher. Both methods are capable of providing sufficient force to effect wedge and socket separations on draglines with up to 78-yd3 buckets under normal conditions.

Jan 1, 1984

By A. Nieto

This article is a review of previous discussions about underground mining method selection and classification with the purpose to clearly define and classify the two groups of variables (indicators) involved in the mining selection process: key deposit indicators (KDIs) and key mining method indicators (KMIs). This paper provides a simple and clear approach for the classification and selection of a feasible underground mining method based on a predetermined set of favorable deposit characteristics, which are defined as key deposit indictors (KDIs). This article also gives a summary of the key advantages and disadvantages associated with every underground mining method based on their key mining indicators (KMIs). The selection method given in this paper is based on defining field KDIs and comparing them to the KDIs that are favorable to every considered mining method. By cross validating a matrix of favorable KDIs, the paper presents a simple approach to rank several underground mining methods using a scale from favorable to less favorable accordingly to the ore deposit characteristics (KDIs). KMIs are used to further complement KDI rankings by analyzing every method’s KMI performance based on the expected productivity of the mining operation being considered. To further assist the reader through the selection process, this paper gives basic sketches representing each of the primary underground mining methods discussed in this paper. Each method is given using the same 3D isometric view as spatial reference to assist the reader with visual interpretation and comparison between methods.

Jan 1, 2010

By P A. Tilyard

There have been enormous changes in mineral processing in the past four decades. For example grinding mill power has increased by an order of magnitude, regrinding is done to -10 microns and flotation machines are 100 times bigger. Operating staff have unprecedented opportunities for online monitoring and performance control of mineral processing plants. Sophisticated instruments can provide a plethora of data characterising the mineralogy and surfaces of particles. Digital computers allow complex calculations on huge amounts of data including modelling and simulation of machine and plant performance. However, all these changes have not necessarily lead to better metallurgical results. An analogy can be drawn with the thoroughbred racing industry in Australia. Significant advances in scientific knowledge in animal genetics, physiology, biomechanics and nutrition applied to the business have resulted in only a two per cent reduction in winning times for the Melbourne Cup and Caulfield Cup since the 1920s. A critical look at some mineral processing metrics suggests similar failures to improve performance despite putting in more resources. In fact certain parameters such as operating times and plant start-up performance are considered to have remained static or even deteriorated. There has been an emphasis on &apos;process&apos; at the expense of &apos;outcomes&apos;. The industry&apos;s strength has been in finding technical (or &apos;hardware&apos;) solutions while its weakness has been at the people end of the business in maximising and consolidating the gains from the technologies. Some trends in plant design over these years have exacerbated the apparent deskilling of operating and technical staff. Despite unparalleled options for communications, some staff are embarrassingly uninformed about technical developments in their fields. The &apos;boom and bust&apos; cycles of the industry, together with trends in tertiary education and the effects of fly-in, fly-out (FIFO) operations, raise serious questions about the sustainability of human capital in the mineral processing sector. This paper by two experienced mineral processing engineers, with contributions from other senior practitioners, reviews these trends. While there may be an element of &apos;the older we are, the better we were&apos;, it is an attempt to identify the issues and propose solutions.

Jan 1, 2009

By Guy E. Dent, Robert S. Sandford, W. T. Millar, Hugo E. Kuehn

"INTRODUCTION AND SUMMARYDuring the latter part of 1943 a magnetometric survey was conducted by the Geophysical Division of the Bureau of Mines at the mine, Putnam County, N. Y., in an endeavor to locate a segment of the body that reports state was cut off by a fault. The Mahepac mine was abandoned about 1895 after producing nearly 1,000,000 tons of high-grade magetite iron ore. The results of the investigation indicate the termination of the ore body by ""pinching"" or a displacement of such magnitude as to place any extension at a considerable distance the original ore body. This report describes the work done on the project and presents the data obtained. ACKNOWLEDGMENTSThe Bureau of Mines has been investigating deposits of critical and essential minerals in the United States and Alaska since 1939. The Mahopac mine was visited by W.T. Millar, an engineer of the Bureau of Mines, on June 5, 1943, accompanied by Dr. William Agar of the Federal Survey, and again on July 29, 1943, accompanied by Dr. A. F. Buddington and H.F. Hawkes, both of the Geological Survey.The mineral investigation was under the general supervision of Paul M. Tyler, formerly regional engineer, Eastern Region; J. D. Bardill, formerly district engineer; and Dr. F.W. Lee, formerly chief. Division, Geophysical Exploration. The work was done under the immediate supervision of W. T. Millar, project engineer. The Geophysical Survey was made by Hugo Kuehn and Guy E. Dent."

Sep 1, 1948