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By J. Saunders, N. Pretorius, G. Krafft, T. P. Katakwa

Imagine being able to see all the future planned mining activities in real time. This is exactly what SIMS (Short Interval Management System) will enable you to do. SIMS is a real time short interval control system that continuously measures and sets optimised plans for mining production processes. The system utilises algorithm-based software that takes resources (people, equipment, tasks, and workplaces) and gives you the best achievable plan. The algorithm was developed using methods found in the field of metaheuristics. A metaheuristic is a strategy to designed to efficiently search for optimal or near optimal solutions to problems that are very complex computationally. (Glover, 1986) There are several algorithms that have been developed to solve optimisation problems which are difficult to solve using traditional techniques. This has given rise to a field called evolutionary computing. (Simon, 2013) Examples of these techniques are genetic algorithms, particle swarm optimisation, and ant colony optimisation. These methods are used to solve problems in a variety of fields. As an example, Kok and Lane (2012) used particle swarm optimisation for equipment allocation in a mechanised underground mining environment. The first SIMS deployment took place in a platinum underground tabular mechanised mine near Burgersfort (province?) from 2017-2019. This included the development from a paper-based system to a fully operational online system. SIMS then moved to a second site and is currently being tested in a second platinum underground tabular mechanised mine in South Africa. Full deployment of the system is currently being phased in. SIMS was built in response to issues that have been plaguing the mining industry for years. These issues are all aligned into one major problem statement: how can we optimise mining production processes without compromising safety? This product was developed by combining years of mining experience with software development. SIMS is based on a four-pillar concept. Safety, productivity, accountability, and business improvement. SIMS uses a set of pre-configured mining and production rules, and with the resources that are available, to determine valid short term production plans. A background algorithm then determines the optimum plan to be executed. The system continuously produces a set of job cards that are pushed to respective operators on their allocated tablets. The management portal component allows you to view and manage all current and planned work on any connected device available. This allows real time visibility of completed, current, and planned work to operators, service departments and management, i.e., seeing into the future.

Sep 1, 2021

By Robert A. Cummings

Disintegration of the immediate shale roof in coal mines interferes with ventilation, production, and safety. The effect is seasonal and correlates with high levels of moisture in the intake ventilation air. Disintegration, though not completely understood, is caused by shale dilation and weakening upon exposure to atmospheric moisture. Fluctuating moisture conditions are particularly deleterious, and may be at least partially controlled by "tempering" the air before it is brought to the working places. Roof behavior was studied in an operating mine during a 12-month monitoring period. This approach can be used in developing criteria to reduce or prevent shale roof deterioration.

Jan 1, 1981

By Guojun Qi

This work relates to wafer bumping technologies for flip chip packaging applications in the electronics industry. Nickel and its alloys are alternative under bump metallization (UBM) materials because of their slower reaction rates with Sn-based solder as compared to Cu-based UBMs. In this study, we compared the morphologies of the intermetallic compounds (IMC) formed between Sn-bearing solders (Sn3.5Ag and eutectie Sn-Pb) and two types of nickel- based UBMs, electro less Ni-P (EN) and sputtered nickel. Both chunky-type and needle-type of intermetallics were observed between the EN UBM and the solders. In the case 'of sputtered Ni UBM, there is only a layer of scallop-type intermetallics formed, The morphology change and growth kinetics of the IMC in thermal aging process were analysed. Kirkendall voids were noticed from samples ofSn3.5Ag solder vs Ni-P UBM that have undergone prolonged thermal aging at high temperature.

Jan 1, 2003

By Izabelle Lannes Salgueiro Ferreira

O presente trabalho tem como objetivo mostrar o Programa da Qualidade desenvolvido na Gerência de Laminação a Quente da Votorantim para aperfeiçoar o sistema de gestão da qualidade. Tendo como base a melhoria no método de análise dos parâmetros de processo e produto, foi identificada a oportunidade de desenvolver um modelo integrado com a finalidade de coletar resultados dos parâmetros produtivos de forma instantânea, obtendo o controle online do processo e produto. A implantação do ProQuali possibilitou a realização de análises de campanha para produtos críticos pela equipe técnica e auxiliou a equipe operacional na tomada de decisão online durante o processo. Com isto foi possível evidenciar uma evolução significativa nos principais indicadores do laminador: índice de rendimento metálico (RM), utilização (IU) e geração de produtos não conforme (NC).

Oct 30, 2017

By J. Ludden

By Sims Some two years ago we began investigating low coke button bituminous coal for use at our Bound Brook, New Jersey plant as a replacement for anthracite. Since August, 1957 the plant has been operating continously on this coal with the exception of a new 200,000#/hr, cyclone boiler. This study was motivated not from our desire to conduct combustion research, but for the sole purpose of reducing our steam costs, The indications were that the economics were greatly in favor of the use of the bituminous coal. The attempts to reduce the costs have developed some knowledge that has enabled this program to succeed reasonably well as will be discussed later by Mr. Ludden. The production of steam size anthracite is dependent upon either the reclamation of old culm banks or the breakage in the production of the domestic sizes. The anthracite industry has not as yet been able to cut, its mining costs to the point where the production of steam sizes has become a profitable business. This has resulted in two basic problems: (1) A constantly rising price in an attempt to have those sizes carry their share of the cost and, (2) Periodic shortages of supply when the demand is good but the market price prohibits the mining of anthracite to produce those sizes only, These conditions have made the long range forecast appear as though the price would go even higher and/or the supply at times be critically short.

Jan 1, 1958

By M. Pope

By 1950, packaged oil and gas fired boilers were on the market for capacities up to 30,000 lbs./hr. By 1962, capacities were up to 100,000 lbs./hr. and even higher when separate heat traps (economizers and air preheaters) were attached to the boiler packages. During this period, complete packaged coal fired boilers were developed into the 10-15,000 lbs./hr. range. Oil and gas fired plant designs became very compact, "basementless", and far: less costly than the coal fired plants of any capacity. Coal fired plants remained large and expensive, required field erection of boilers and required basements. With the spectacular strides made in automation, oil and gas plants became far less costly to operate, requiring only the part-time attendance of a single operator. Some advances were made in coal fired plants, but not to the degree attained by the fluid fuel competition.

Jan 1, 1965

By Peter A. Hacquebard

"The coals of the Sydney and Pictou coalfields are generally classed as high volatile ""A "" and medium volatile bituminous coals but there are significant differences within and even beyond this rank. These are related to the observation that the coalification in eastern Canada is essentially post-deformational, resulting in a general increase of rank with depth in individual seams.Exploration drilling in the Sydney coalfield has shown that the rank increases offshore to M. V. bituminous at mineable depths and in the Pictou field to L. V. bituminous coal. There is also a marked easterly shift in rank within one seam at the same depth at Sydney, with the result that M. V. coal will be reached sooner in the Donkin Reserve area (at 700 m depth) than in the Lingan-No , 26 Reserve area (at 900 m depth). These rank changes are important for the manufacturing of metallurgical coke as shown with coke stability predictions based on petrographic analyses. The L. V. coal of the Pictou field can be used for blending purposes and is the only known L. V. deposit of mineable thickness in eastern Canada.In addition, the vertical rank changes between seams have been studied in ten boreholes. They are not constant within the confines of the Sydney coalfield. Four separate areas can be recognized, each with different coalification gradients, which can be related to changes in the paleogeothermal gradients . Variations of 2.5 degrees to 6. 7 degrees CI IOO m are indicated and geological causes for these changes are suggested.IntroductionThe Sydney coalfield is the largest and most important field in eastern Can ad a, and although it has been in production some 200 years, the remaining ""demonstrated "" resources of 1.6 billion metric tons can extend its production capability for at least another 100 years. All coals mined are high volatile "" A"" bituminous and have been used for both thermal and metallurgical purposes. For the latter rank variations even of a minor scale are of critical importance for the manufacturing of metallurgical coke.The significance at the present time of the Pictou coalfield, which has only modest remaining "" demonstrated"" resources of 60 million metric ton s, lies in the discovery in 1975 of a 14-million-ton deposit of low volatile bituminous coal. It is the only known low-volatile coal in eastern Canada and is suitable for use as a blend for metallurgical coal. As such, it could supply the Sydney coke ovens for a period of 30 years at the current rate o f coke production and replace imported American low volatile coal.Consequently, coal rank studies of the Sydney and Pictou fields are important not only from a geological point of view, but also because of economic considerations."

Jan 1, 1984

By Irven A. Jacobson

This literature survey consists of references dealing with gaseous state thermal decomposition reactions of organic nitrogen and sulfur compounds. The reference source for the survey was the Chemical Abstracts from 1930 to 1956, inclusive. Original articles were not studied. The starting date was set at 1930 because previous to this time much of the work is questionable. This report is in three parts: Part I lists nitrogen compounds; Part II, sulfur compounds; and Part III, compounds containing both nitrogen and sulfur. The organization of the classes of compounds is alphabetical: Part I - amides, amines, amino acids, ammonia, azides, azines, azo compounds, heterocyclic nltrogen compounds, hydrazine, nitrates, nitriles, nitrites, nitro compounds and miscellaneous nitrogen compounds; Part II - disulfides, sulfides (including double and triple sulfides), thiols, thiophenes and xanthates; Part III - thioacid amides, thiazoles, thiocyanates and thiuram disulfides. A class formula is included with each class name. The R's used in these class formulas may refer to hydrogen or to the same or different radicals when more than one R appears.

Jan 1, 1960

By W. R. A. Graeser

"The Nordenham finishing mill is situated in the town of Nordenham, Fede1•al Republic of Germany, on the banks of the Weser River opposite the town of Bremerhaven, with access by water to the North Sea.The unfinished fibre, shipped j?•om Deception Bay during the sub-Arctic summer shipping season, is unloaded from bulk ocean carriers, stored and then processed throughout the year until the following shipping season. This paper describes the unloading and storage facilities,the finishing mill and the finished-fibre storage arrangement. Details of environmental and dust control practices and West German environmental standards are discussed. A resumé of fibre markets is included."

Jan 1, 1976

By ERIK CHARRIER, ADITYA JUGANDA, Jürgen Brune, Patrick Maier, Gregory E. Bogin Jr

Confined explosions are a major risk in underground coal mine operations. Depending on confinement, ignition location and obstacles in the flame path, methane explosions can transition to detonations. As a result, the severity of mine explosions ranges from minor damage to loss of lives and permanent mine closure. Experimental results have shown that the inclusion of obstacles can significantly increase the flame propagation velocity by inducing turbulence. This research focuses on explosion experiments in a 71 cm diameter, 30.5 m long reactor that includes rock piles as obstacles along with developing the corresponding CFD model that captures the observed flame behavior and interaction with the obstacles. The rock rubble increases the flame front propagation velocity by 500% compared to the maximum velocity observed in the empty reactor experiments. The 2D and 3D CFD models predict the experimental flame front propagation velocity, whereas the 3D model shows a more explicit conformity than the 2D model. Although the computational time to complete the simulation is much less for the 2D model than for the 3D model, the 2D model is not sufficient to simulate cases with rock rubble since it cannot capture the propagation of the flame through the small voids between the rocks with the same effective blockage ratio as the 3D model. The validated CFD model can be scaled up to simulate methane explosions in full scale mine and industrial settings.

Nov 20, 2023

By W. A. Hooker

This portion of Mexico is quite beyond the ordinary routes .of travel, and is seldom visited. Its mines have not the record of enormous wealth which has recently attracted foreign capital to other parts of the republic; but for many centuries it has been a mining country, and at some periods evidently a productive one. In 1881 the writer visited the State and spent some time in the inspection of the mines. The absence of published information regarding its mining industry is his apology for presenting to the Institute these notes on the subject. Oaxaca is, with one exception (Chiapas), the most southerly of the Mexican States. It extends from latitude 18o 20' to 15' 45' N.— about 180 miles, by some 300 miles, in an east and west direction, and embraces a large part of the Isthmus of Tehuantepec. The coast-line is wholly on the Pacific. The State has an area of 27,470 square miles, nearly that of the State of Maine, and a population estimated at one million, or thirty-six to the square mile. The great continental Cordillera which farther north and west expands into broad table-lands, is here converged into narrower limits and occupies the greater portion of the country; the main

Jan 1, 1887

By Kenneth L. Clifford, Thomas G. White

Many changes have occurred in lead-zinc milling in the U.S. since the 1970 Lead and Zinc Symposium. New mills have been built, novel flowsheets devised, and the use of process control techniques is increasing. The Missouri concentrators produced in 1976 more lead and zinc concentrate than those in any other state. The Tennessee mills produced nearly as much zinc concentrate in 1976 as Missouri and with some very highly developed flowsheets. Progress in the Western U.S. is centered around new operations in Colorado and Utah. New mills in New York and Missouri incorporate many of the newer control concepts. Most of the older concentrators have undergone flowsheet changes to accomodate different ore types or because of the availability of new and better equipment.

Jan 1, 1977

NEW MEMBERS The following list comprises the names of those persons who became members during the period Nov. 10 to Dec. 10, 1915: BARTH, ERNEST, Petroleum Geol Box 552, Tulsa, Okla. BEROLZHEIMER, D. D.,.Chemist; Librarian, Barrett Mfg. Co., 17 Battery Pl., New York, N. Y. BLIEK, PIERRE FRANCISCO, Mgr., Compania Minera de Oruro, Oruro, Bolivia, So. Amer. BLOCS, JAMES A., Met 1076 1st Ave., Salt Lake City, Utah. BULKLEY, RALPH G., Mine & Mill Supt.; The Montezuma Mines & Mills Co., Montezuma, Colo. BURRAGE, ALBERT CAMERON, JR., Met. Engr.; Director, 85 Ames Bldg., Boston, Mass. CABELL, CHARLES ARNOLD, Vice-Pres Carbon Coal Co., Carbon, W. Va. CHAPMAN, LEWIS CARL, Economic Geol Producer Oil Co., Houston, Tex. CHOFFEL, FLAVIEN AURELIEN, Mgr Ingersoll-Rand Co., Paris, France COY, HARLEY A., Mine Supt American Zinc Co., Mascot, Tenn. DITTMANN, C. 0. ADOLF, Cons. Engr., Beer, Sondheimer & Co., Inc., Santiago, Chile, So. Amer.

Jan 1, 1916

By M. N. Chandraprabha

Arsenopyrite is often associated with sulphides like pyrite, chalcopyrite and galena in refrac-tory gold ores. Selective flotation of arsenopyrite from associated sulphides is desirable for effective gold extraction when the gold is preferentially associated with the arsenopyrite matrix. By contrast, presence of arsenopyrite in flotation tailings poses a serious environmental threat due to arsenic dissolution. To prevent arsenic contamination from the mine wastes, it would be more economical and environmentally beneficial to remove this mineral during the froth flotation step. Use of Acidithiobacillus thiooxidans in the detoxification of arsenic containing sulphides is outlined in this pa-per. Biomodulation using Acidithiobacillus thiooxidans resulted in the preferential depression of pyrite from arsenopyrite. By suitable conditioning with cells and collector effective separation of arsenopyrite from pyrite was achieved. Biomodulation with wild cells did not yield separation of arsenopyrite from chalcopyrite. However, bacterial affinity could be induced to a desired sulfide mineral through environmentally controlled adaptation techniques. Through the use of arsenic-adapted bacterial cells, selective removal of arsenopyrite from chalcopyrite was readily achieved.

Jan 1, 2014

By Michael Rieber

Rail cars are referred to as "yellow-balled" when they are sufficiently old or damaged to preclude their efficient operation on long-haul or main line routes. For most coal carrying railroads, their alternative value is salvage. This, however, does not necessarily preclude their effective use, on a limited basis, by small mines located near existing trackage. Because of age, the sizes of these hopper and gondola cars ace currently 50 and 70 tons rather than the 100 tons commonly built at the present time. As a gathering system, yellow-ball rail could provide an alternative, particularly in Kentucky, western Pennsylvania and west Virginia, to coal trucks, conveyor belts and pneumatic pipelines [4, p.17], belts and pneumatic pipelines. Rail service of this type provides a limited alternative to track abondonment, a possible financial return to a railbank [3], a direct contribution to service demand on main lines, and a means by which many small eastern coal mines could retain or regain competitive viability [4]. In terms of energy efficiency, compared to trucking coal, the total direct energy impact (fuel) of yellow-ball rail can be expected to range from 280-990 Btu/ton-mile while that for trucks ranges from 1850-3120 Btu/ton-mile [2].

Jan 1, 1977

By X. Cao, A. Birur, R. R. Chromik, J. Cuddy, P. Wanjara, J. Gholipour Baradari, T. Shariff

In this study, 3.1 mm thick Ti-5553 (Ti-5Al-5V-5Mo-3Cr) butt joints were autogenously welded using a 4 kW continuous wave Nd:YAG laser. The effect of welding speed and defocusing distance on the weld quality was investigated in terms of the surface morphology, welding defects, microstructure and hardness. Welds with full penetration were achieved at a defocusing distance ranging from -1 mm to 0 mm and welding speeds from 2.25 to 6.0 m/min. Underfill and porosity were the two main defects most frequently observed but within the optimum process window these defects could be maintained to meet aerospace specification tolerances. The fusion zone (FZ) consisted entirely of retained beta with a refined dendritic morphology. Compared to the bimodal alpha (a) + beta (ß) microstructure of the base metal (BM), the dissolution of the a phase was observed in the heat affected zone (HAZ), which led to an 11 % decrease in hardness from the BM to the FZ. To determine the tensile properties of the welded samples, an automated 3D deformation measurement system was used to measure the local strain in the weld region. The yield strength (YS) and ultimate tensile strength (UTS) increased with increasing welding speed with a highest joint efficiency of 75 % being achieved, albeit with a concomitant reduction in the ductility.

Jan 1, 2010

By Edna A. Dancy, Gerhard J. Derge

The specific conductance of FeOx,-CaO melts in contact with iron was found to decrease from 200 ohm-1 cm-1 for FeO, to 40 ohm-1 cm-1 for a melt containing 26.3 pct CaO at 1400°C. The temperature coefficient was positive at all compositions, but became smaller at high CaO contents. Current efficiencies for electrolysis increased from 2.5 pct in FeOx to 17.3 pct at the high CaO composition, indicating a change from predominantly electronic conduction to conduction with a substantial ionic contribution. It was shown that Ca++ ions as well as Fe++ ions carry the ionic current. A subsidiary investigation on the apparent effect of atmospheres of argon, helium, and nitrogen on the electrical conductivity showed that this could be correlated with surface temperature losses, which varied with the thermal conductivities of the gases and resulted in precipitation of metal by the reaction 3 Fe++ = 2 Fe+++ + Fe. The work described in this paper is offered as a contribution to the general fund of knowledge concerning metallurgical slags. Measurement of electrical conductivity and electrolysis are comparatively trouble -free methods for investigating molten materials, but, although these methods had been used for complex slags, it was not until the work of Bockris et al.1 that the approach of examining simple binary slag systems was employed, and CaO-SiO2, MnO-SiO2, and Al2O3-Si9 were studied. Two groups have performed work of particular relevance to the present investigation. Inouye, Tomlinson, and chipman2 studied the conductivity of wustite as a function of temperature and of the addition of 5 mol pct of a number of oxides, including CaO. They concluded that molten FeOx in equilibrium with iron is a semiconductor. Simnad, Derge, and ceorge3 demonstrated the ionic nature of liquid iron silicate slags and also concluded that, although the conductivity of FeOx in equilibrium with iron is predominantly electronic in nature, there is a small ionic contribution. The work reported here on FeOx,-CaO slags consists of three main parts, namely, the determination of the specific conductance over a wide composition range, an investigation into the nature of the conductivity through current-efficiency measurements over the same composition range, and an attempt to identify the current-carrying ions, as well as a subsidiary investigation on the apparent effect of the nature of the inert atmosphere on the conductivity. EXPERIMENTAL Materials. The slags, varying in composition from FeOx to 27 pct CaO, were prepared by heating reagent- grade Fe2O3 in an ingot iron crucible with a suitable amount of CaCO3 and, in some cases, powdered iron, in air. This prefused material was then used for the runs. At the end of each run the cell was removed from the furnace and quenched by immersing the bottom half in water. After crushing, the slags were analyzed for calcium and total iron by the usual wet methods. The oxygen content was obtained by difference. Specific Conductance: Apparatus and Method. Fig. shows the experimental setup, with the conductivity cell and leads of ingot iron. The standard four-probe method for measuring high conductivities was used. In this, the potential drop across the unknown resistance is compared with the potential drop across a known resistance connected in series, i .e., same current through both resistances. Thus there are both current and potential leads to the center electrode and to the crucible, which acts as th other electrode. Both ac and dc circuits were available for the measurements; they have been described in earlier work performed in this laboratory.4,5 The geometry of the cell was such that the center electrode was equidistant from the bottom and sides of the crucible. This ensured that the current path was the same irrespective of the magnitude of the conductivity of the material in the cell. Cell constant were measured with KC1 or NaCl solutions, which have considerably lower conductivities (0.0013 to 0.25 ohm-' cm) than the slags, and this precaution in design made sure that the determined cell constants applied to the cells with contents of any conductivity. The cell-constant determinations were made with the ac measuring circuit to prevent polarization. The four-probe method eliminates lead resistance but not the resistance of those parts of the center

Jan 1, 1967

By Valter Félix Júnior Carvalho

A operação de um porto de minério é um campo fértil para boas práticas em integração de sistemas. Por tratar um produto normalmente sem alteração de características ao longo do processo, é possível analisar essa integração exclusivamente sob a ótica dos sistemas envolvidos. Dada a quantidade de sistemas independentes e complexos, o estabelecimento de interfaces se torna um fator essencial para o sucesso do projeto. Por outro lado, a necessidade de persistência de informações consolidadas, como informações de rotas e de planos de carregamento, torna interessante o uso de Sistemas de Bancos de Dados (SGBD) e sistemas legados. A integração de todos os sistemas necessários num projeto conciso com um fluxo de informações completo e eficiente também exige um gerenciamento vertical, que possa cuidar do acoplamento de todos os níveis de forma eficiente. Nesse mesmo caminho, o desenvolvimento coordenado com metodologias que permitem a interdisciplinaridade é essencial para complementar a tarefa da gestão, trazendo a preocupação com uma integração eficiente para o nível de desenvolvimento.

Aug 16, 2017

By Maurício Covcevich Bagatini, Maycon Athayde

Water consumption reduction in pellet feed operation is of paramount importance. Compared with traditional ball mills, high-pressure grinding rolls (HPGR) play an important role in Blaine surface area (BSA) generation to improve agglomeration properties, although stability is still a challenge. Grindability improvement of existing operation has a direct impact on the performance of the filtering and pelletizing operation. The results of this study, as a pregrinding operation, can be applied not only in new operations but also in existing ones, helping the operator control process variation in a more effective way while ore hardness increases. 

By E Corpuz, J Weissman, S Winter, R Evans

The surface-to-inseam (SIS) directional drilling technique has been utilised at Oaky Creek Coal for more than a decade to predrain both the Oaky No 1 and Oaky North mining areas. The cumulative drilling program constitutes a total of 140 lateral and 200 vertical holes, and 405 km of lateral drilling.The use of SIS gas drainage has been successful with the following site-specific benefits being recognised:ability to drain German Creek seam gas contents to residual gas levels of new mining areas within an 18-month period from commencement of well productionstructural geological verification of the mine design well in advance of development mining occurring in an areaability to conduct successful predrainage of the overlying Aquila seam to reduce subsequent goaf emissions.Appropriate and up-to-date geological knowledge during the design and drilling process is a significant influence to achieving success. Vertical production wells need to be located in a position that is most effective to remove water from hole. The lateral hole should not include intersections with significant geological structure.SIS drilling provides continuous seam roof/floor data to help define seam geometry and locate geological hazards with high accuracy. In faulted ground and with variable seam gradients, SIS data can resolve geological ambiguities from seismic sections and enhance seam correlation that would otherwise be available only from discrete and closely-spaced infill vertical exploration drilling.Here, we review some examples of SIS configurations and practice to highlight key learnings in drilling long inseam holes (up to 1900 m per arm) ahead of development and mining. Aspects on prerequisites, evolution of network design, tolerances and drainage outcomes in a variety of geological situations are discussed as technical basis towards a viable and effective SIS drilling program.CITATION:Corpuz, E, Evans, R, Weissman, J and Winter, S, 2015. Surface-to-inseam (SIS) drilling at Oaky Creek coal mine – SIS design aspects and drilling environment, in Proceedings The Australian Mine Ventilation Conference, pp 93–104 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015