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By M. Jacobs

Keywords: Smelting, converting, sulphide, sulphide smelting, platinum, platinum group metals, PGM, base metals, nickel, copper, matte, slag, furnace, electric furnace, Söderberg, electrode, granulation, converter, flash drier, sulphuric acid, acid plant, Ausmelt, Sirosmelt, pyrometallurgy, metallurgy, Anglo Platinum, South Africa Waterval Smelter complex is situated in Rustenburg, in South Africa?s North West Province. The smelter objective is to process wet concentrate to produce crushed, slow-cooled, sulphur-deficient nickel-copper matte rich in platinum group metals (PGMs), gold, and base metals for despatch to the Magnetic Concentration Plant at the Base Metals Refinery. Throughout its history, the smelter complex has been continuously upgraded in line with increasing production demand, changing feeds, environmental initiatives, and advances in available technology. The smelter receives filter cake and slurry from Anglo Platinum concentrators and joint ventures. Wet concentrate is fed through a flash drying process utilising coal-fired, fluidised bed hot-gas generators, to produce dry feed material for the electric furnaces and slag-cleaning furnace. For primary smelting, two electric furnaces are used, each with a rated capacity of 34MW. Furnace matte, containing the bulk of the base metal sulphides and PGMs, is tapped periodically into refractory-lined ladles and granulated using high-pressure water jets, then dried through electrically powered pneumo-driers to become the main feed to the Anglo platinum Converting Process (ACP). Slag is tapped semi-continuously, granulated, and treated through the slag mill. The ACP treats the combined matte output of Waterval, Polokwane, and Mortimer smelters. It is a top-blown furnace, with furnace matte, air, and oxygen being injected into the converter via a lance submerged in the slag. Converter matte is tapped and bottom cast into moulds, slow-cooled, crushed, and despatched to the refineries. Slag is granulated and dried for recycling to the slag-cleaning furnace. ACP slag is fed to the slag-cleaning furnace along with a reductant and a sulphur source. Slag-cleaning-furnace matte is granulated for processing by the ACP, while slag is granulated and processed in the slag mill. The slag mill and flotation circuit treats granulated slag from the electric furnaces and slag-cleaning furnace to recover entrained matte containing valuable PGMs and base metal sulphides.

Jan 1, 2006

By Taylor R. G

This paper reports a biogeochemical study of the Siberia lode of the Herberton tin field. Soil near the orebody contained high levels of Fe, Cu, Pb, Sn, As, Mld Mn. Polycarpaea spirostylis and Indigofera dominii were associated with these high levels but several other species apparently could not tolerate them. The potential of these species as indicator plants is discussed.

Jan 1, 1975

By Hannan J. C

In New South Wales, development applications for major coal mining proposals are determined by the Minister for Planning and Environment and applications for mining leases and other mineral titles are dealt with by the Minister for Mineral Resources. The environmental conditions placed on the development consent, the coal mining lease and the approvals and licences under the pollution control legislation, amount to a substantial component of any new project's planning and commissioning considerations.An outline is presented of the framework within which various approvals are granted and conditions for environmental management are imposed upon mining projects. The principles and concerns, as perceived by the regulatory authorities, on which the majority of approval conditions are based are also outlined.No attempt has been made to analyse the extent to which these principles or standards are achieved in practice, nor to discuss the degree to which some of the conditions are achievable with the current status of technology and economics in the coal industry.

Jan 1, 1987

By M. M. Veras, C. H. Sampaio, A. S. Young, D. Neto, C. O. Petter

"Due to new technological developments, automatic sensor based sorting has made progress within industrial minerals, precious metals, diamond, and coal mining in recent years (Lessard et. al. 2016). In order to re-introduce the technology to other mining sectors, this research discusses its application to iron, manganese, and zinc ores through test works performed by the authors. These test works were performed using Dual Energy X-ray Transmission (DE-XRT) sensor technology. In each case, pre-concentrations of the ore were created demonstrating the possibility to reduce waste material, energy costs, and water consumption while improving product quality of the ores. INTRODUCTION Sorting of mining ores is as old as mining itself (Salter, 1991). Sensor based sorting applications in coal mining began as early as the late 19th century (Louis 1928). New sensor technologies were developed and implemented sequentially for uranium, nickel, coal, and gold mining (Refining, 1949, Rose et al, 1950, Bloomfield et al, 1966, Clayton et al, 1987, Robben and Mosser, 2014). While these sensor technologies were developed decades ago, computational capacity to keep pace with the vast amount of information required utilizing the sensor technology did not arrive until recently (Lessard et. al., 2016). The sensor based sorting (SBS) process was effectively described by Salter and Wyatt in Minerals Engineering in 1991, and Wotruba and Harbeck in 2010 in the Ullmann’s Encyclopedia of Industrial Chemistry under Sensor Based Sorting. Both descriptions include the following key steps: 1. Presentation of the material or particles. 2. Examination or detection of the material or particles. 3. Processing or analysis of the data generated. 4. Physical separation of the material or particles by external means. Effective presentation of the material or particles is achieved when the sensor is capable of identifying each particle individually. This step requires that each fragment of the material be isolated, and it often involves acceleration of the material fragments by chute or mechanical means, as well as the spreading of particles by vibratory feeders (Salter and Wyatt, 1991, and Wotruba and Harbeck, 2010). The isolated particles typically are conveyed into an area wherein they are subjected to electromagnetic irradiation (except in cases of some radioactive ores), either in the form of x-ray, visible light, infrared, or other energies. A wide range of applications for sensor based sorting exists in the literature. The majority of applications fall into one of two camps, (1) pre-concentration of mineral ores, or (2) characterization of the material during processing (Buxton and Benndorf 2013). While there is much to be gained from in-line material characterization and the resulting control both of quality and processing, this article focuses primarily on the camp of pre-concentration of mineral ores."

Jan 1, 2017

By Albert L. Toenges

A phase in strip mining of bituminous coal is the overturning of the surface of the land. The purpose of this report is to acquaint the operators and others interested in stripping with the work that has been done in certain States to reclaim the surface of land from which the coal has been removed by this method of raining. The preparation of this manuscript follows an extensive study of the subject in the field in the course of which a large number of strip mines were visited. ACKNOWLEDGMENT The information used in the report was obtained through the courtesy and cooperation of the operators of the mines visited, State officials and educational institutions, and others interested in the subject.

Jan 1, 1939

By Andrzej Tejchman

Calculation of pile foundations should possibly truly reflect its real work, mainly with respect to the value and distribution of settlements, pile internal forces and bending moments within a slab. Many empirical and theoretical methods serving for an assessment of the settlements of pile group overestimate its actual values obtained from field measurements (see Tejchman et al., 2001). In the paper a simple engineering method for calculation of pile foundations is presented. The method takes into account the interaction between the slab and a soil together with the phenomenon of non-uniform deformation of the soil-pile subsoil, particularly under large foundations. In the method the scheme of the slab resting on one-parameter elastic subsoil is assumed. The comparison of the calculation results for existing pile foundation with the field measurements shows good agreement between those values.

Jan 1, 2002

By I. Satola, J. Aromaa

In this work we have reviewed methods to classify corrosivity of ground waters. Weight loss and stress corrosion cracking (SCC) corrosion tests have been done for rebar and steel strand. No clear indication of SCC was found. The application of tensile stress to 85 % of yield strength increased general corrosion rate significantly in very corrosive waters. The effect of corrosion protection on the axial behavior of steel strands was determined by double pipe axial tests with different embedment lengths. The results showed a significant difference on behavior between epoxy-coated steel strands, galvanized steel strands and plain steel strand. Dans la présente étude, nous avons passé en revue des méthodes permettant de classifier la corrosivité des eaux souterraines. Des tests portant sur les pertes de poids et sur la corrosion FCC (la fissuration par corrosion sous contrainte) ont été effectués pour les barres d’armature et les torons. Aucune indication nette de FCC n’a été constatée. L’application d’une contrainte de traction allant jusqu’à 85 % de la limite d’élasticité a accru de manière significative la vitesse générale de corrosion dans les eaux très corrosives. L’effet de la protection contre la corrosion sur le comportement axial des torons en acier a été déterminé au moyen de tests axiaux à double tube avec des longueurs d’enrobage différentes. Les résultats ont mis en évidence une différence significative quant au comportement entre les torons en acier à revêtement époxy, les torons en acier galvanisés et les torons en acier standard. In dieser Arbeit haben wir Methoden geprüft, die korrosive Wirkung des Grundwassers einstufen. Gewichtsverlust- und SCC-Korrosionstests wurden für Stahlstäbe und Drahtlitzen durchgeführt. Es wurden keine sicheren Hinweise auf Spannungsrisskorrosionsbrüche gefunden. Bei Anwendung einer Dehnbelastung von 85 % der Streckspannung bzw.Ergebnisstärke stieg die allgemeine Korrosionsrate in stark korrosivem Wasser deutlich an. Die Wirkung des Korrosionschutzes bei axialem Verhalten von Stahldrahtlitzen wurde durch axiale Tests an Doppelleitungen unterschiedlicher Versenkungslänge determiniert. Die Ergebnisse zeigten im direkten Vergleich von epoxidbeschichteten, galvanisierten und normalen Stahldrahtlitzen beachtliche Unterschiede im Verhalten auf.

Jan 1, 2003

By George S. Rice

The prevention of coal-mine explosions has been one of the chief purposes of the Bureau of Mines. In facti the first Federal appropriation relating to mining methods, in 1908, authorized the investigation of the causes of mine explosions and the possible methods of preventing them. When that investigation started the mining industry had not determined the real causes of a succession of terrible coal-mine explosions in various countries, culminating in the great disasters at CoulTièl'es, France, and Monongah, W. Va. Coal dust as an agent of widespread explosions had been under suspicion, and watering to allay the dust was recommended by some mining engineers but the watering of coal-mine dust was adopted in comparatively few mines of the United States and Great Britain, and had not been introduced widely in any country except Germany. Rock dusting, another method of preventing explosions of coal dust, was early tested with success by the Bureau of Mines in its fist gallery at Pittsburgh and, beginnig in 1911, at the experimental mine, Bruceton, Pa. Several of the fist publications i of the bureau suggested that rock dust be used in gaseous or dusty bituminous mines, and in 1915 Technical Paper 842 strongly recommended it. Since that time additional tests in the experimental mine have fully confied this :ft judgment.

Jan 1, 1924

By Sudhir Kumar Kashyap

In underground activities ground control is a challenging problem. It affects safety, production, and efficiency. As per statistics of accident data, ?fall of roof/sides? is one of the major causes of mine accidents. In many cases, our experiences and understanding of soil and rock behavior still fall short of being able to predict how the ground will behave. Presently, empirical approaches to design are widely used in estimating mine support parameters. Under these circumstances, expert judgment plays an important role, and such accidents can be obviated with accurate measurement and optimization of data and analysis using the neuro-fuzzy technique of artificial intelligence. Recently, a neuro-fuzzy hybrid approach has become one of the major areas of interest in engineering fields because it gets the benefits of neural networks as well as those of fuzzy logic systems, and it removes the individual disadvantages by combining them on the common features. Neural network and fuzzy logic technologies have common features, such as a distributed representation of knowledge, the ability to handle data with uncertainty and imprecision, etc., like in ground control. Fuzzy logic technique has tolerance for imprecision of data, while neural networks have tolerance for noisy data. In this paper we have focused an intelligent technique, i.e., neuro-fuzzy technique, to approximate the setting load given to the standing support (props) erected for the purpose of supporting freshly exposed roof during underground mining. We have used twelve input variables of rock parameters, and after having trained using a neural network with a sigmoidal function as an activation function, simulation was done to find the output parameter, i.e., the pre-load (setting load)to be applied on props. Outputs of the neural network were again fed to the fuzzy system together with the twelve parameters, incorporating five triangular membership functions for each parameter. Final optimum output was approximated using the MATLAB program, which was found to be satisfactory. Neuro-fuzzy technique has better performance over individual neural networks or fuzzy logic technique.

Jan 1, 2012

By Cabrera M. Manuel C

A fines de 1980, la empresa Minero Perú construyó una operación piloto de monitores y planta de lavado con una capacidad de 1,500 m3/día, incrementando la producción de oro a un 80%. En este sentido, el presente texto señala la producción de oro de esta minera peruana, utilizando dichas herramientas mencionadas. Para ello, se describe la geología, minado, características del monitor seleccionado, características de la bomba de alta presión, metalurgia y las plantas de lavado.

Oct 14, 1980

By E. G. Davis

As a result of interest by the U.S. Department of Energy, the Bureau of Mines conducted studies on comminution of bituminous coal to the 2-um particle size range using the Bureau-developed turbomill. Both "plant grind" size (80 pct minus 75 um) and microsize (minus 10 um) coal can be produced in a single step with the Bureau's turbomill. In 15 min, minus 2.4-mm coal milled in water with steel shot was reduced tc 65 pct minus 75 m and 26 pct minus 2 m, with an energy requirement of 139 kW^h/mt coal. Plant-grind size coal milled in water, with Ottawa sand as the milling medium, was reduced to more than 45 pct minus 2 m in 15 min, at 175 kW?h/mt. Plant-grind coal milled with steel shot was reduced to 57 pct minus 2 um in 15 min, at 138 kW?h/mt. When diesel fuel was substituted for water, the milling of the coal was less effective and less energy efficient. Keeping the pulp dispersed was critical. Without an effective dispersant, the slurry became very viscous with increased milling time, resulting in higher energy requirements, low heat dissipation, and poor grinding efficiency.

Jan 1, 1987

By E. Viljamaa

In this research, earlier developed information integration method and novel web technologies are applied to intensify infrastructure construction process control. The applied method uses semantic methods to integrate scattered information that is later on exploited by process management using state-of-the-art web technologies. The applied method and web technologies not only improve the process management situation awareness by integrated up-todate multi-source process data but also provide platform independent access and visualization tool for process data. Utilization of such technologies potentially lead on cost savings, make processes safer and also more environmentally friendly. The integration method also enables intelligent queries to the integrated data making possible to use machine based inferring to the data.

Aug 1, 2013

By Kenneth G. Skinner

Diatomite, also known as diatomaceous earth, diatomaceous silica, kieselguhr, and moler, has been used extensively for many years, but only during the past two decades has it become an important industrial mineral. United States sales for 1.936-38 totaled almost 280,010 tons,7 but relatively little (with the exception of that sold by an Oregon company affiliated with a larger California company) was sold by Pacific Northwest producers. In attempting to develop some of the many Pacific Northwest diatomite deposits, these producers have been handicapped by lack of published technical information regarding processing methods and the suitability of different deposits for specific uses. To determine some of the physical and chemical properties of known Pacific Northwest diatomites, the present investigation was started in 1938 by the Bureau of Mines in cooperation with the College of Mines, University of Washington. Figure 1 shows the location of deposits sampled. Because most relatively pure diatomites can be used as concrete admixtures or as inert fillers in rubber, paints, and plastics, this investigation concentrated upon determining some filter-aid characteristics and their relationship to other physical properties. A filter-aid is a powdered material that, when added to solutions to be filtered, improves flow rate, filtrate clarity, or both. Some chemical analyses also were made.

Jan 1, 1944

By F. G. Miller, H. C. Miller

Petroleum technologists and progressive operators constantly are striving to increase the percentage of oil that may to recovered from reservoir rocks through wells. The exhaustive studies that have been made of the function of natural as in the production of oil, for example, have aided operators greatly in increasing the quantity of oil recovered from reservoirs. Natural gas dissolved in and otherwise associated under pressure with oil in reservoir rocks, however, is not the only source of energy available for moving oil through sands to wells. In becoming "reservoir—energy conscious" engineers have learned that in many petroleum reservoirs the edgewater flanking the oil accumulation constitutes a potential source of energy capable, through proper control, of increasing oil—recovery efficiencies materially. No longer is the encroachment of water into the oil— and gas—filled tart of the reservoir considered as an evil to be combatted by devious methods but rather a natural consequence, incident to the withdrawal of nil and as from the wells, that may be used advantageously in lengthening the flowing life of wells and increasing the economic recovery of oil and gas.

Mar 1, 1938

By Rick Collins

Presentation Agenda 1.Sudbury Basin 2.Diamond Drilling 3.Planned Production 4.Safety 5.Timeline 6.Sustainable Development 7.Scope Elements 8.Progress 9.Delivery Approach 10.Owners and EPCM Roles 11.Contract Styles 12.Mine Systems & Technologies 13.Q & A

May 1, 2009

By John W. Moore

The discovery of porphyries in petroleum by Treibs (17-19) is one of the most significant achievements relating to the origin of petroleum. The presence of these remnants of chlorophyll and hematin in petroleum has immediate practical interest in several aspects of the petroleum industry. Because of their interfacial activities and film-forming tendencies, the metal-porphyrin complexes may be expected to affect the wettability of petroleum-reservoir rock surfaces and influence the flow of fluids in these reservoirs. Also, studies of the relationship of trace elements and porphyrins in petroleum may be expected to yield valuable information on source beds and petroleum migration. Finally, the extreme stability of several metal-porphyrin complexes complicates removal of these metals from some petroleum stocks where they exert deleterious effects on processing and utilization. Metal-porphyrin complexes are commonly associated with the asphaltic residues of crude oils in which they occur (8, 9, 15). However, investigations in this and another laboratory (15) show that small amounts of these complexes often remain in partly refined petroleum products, such as thermally cracked distillates and deasphalted stocks.

Jan 1, 1957

By Gunnar Persson

The borehole pressure/time history of blasting practice is simulated in a twin pendulum apparatus, where the expanding shotfiring gases force two steel slab swingers apart. A pilot installation built at SveDeFo is described. The relevant factors, that govern the use of this test method as a means of classifying explosives with respect to their toxic fume potential, are described.

Jan 1, 1996

By Solomons S. S, Tillmann V. H

The progress of longhole open stoping (LHOS) at Zinc Corporation Limited and New Broken Hill Consolidated Limited (ZC/NBIIC) is described together with the design of a novel sloped wall longhole stoping method which should allow the complete extraction of the orebody without the formation of pillars and with minimal dilution of the ore with sand fill.

Jan 1, 1981

By J. R. Hoskins

This is the final report for Research Contract No. 00101300 (Min. 34) granted by the U.S. Bureau of Mines to the University of Idaho Mining Research Bureau. The research project is entitled "Development of Improved Ventilation Technology for Non-coal Mines and Other Underground Excavations.' The duration of the project was six calendar months, from 16 April to 16 October 1970. The budgeted cost was $34,867.00 of which $31,953.00 was to be furnished by the U.S. Bureau of Mines. The sequence of reporting that follows is to state the objectives as contracted, outline the program of investigation, highlight briefly the important technological factors peculiar to vein-type metal mine ventilation, and describe the normal methods of control. This is followed by the results achieved by the survey, and an itemization of the observed deficiencies in current technology. There follows a section dealing with the adopted Federal Regulations.

Jan 1, 1970

By Frank Parrish

History and performance data of 17 water-injection projects in Cooke and Grayson Counties in north Texas are presented for the purpose of studying and comparing operating practices and oil-recovery techniques. Water is injected into Strawn and Canyon sands of Pennsylvanian age. The principal formation flooded is the Strawn, which ranges in depth from 725 to 6,900 ft in the projects covered. Estimated ultimate recoveries range as follows: Primary, 22 to 494 bbl per acre ft; and secondary; 63 to 296 bbl per acre ft. These figures represent the following percentages of original oil in place: Primary, 10 to 46 pct; and secondary, 8 to 23 pct. Shallower projects; 725 to 1,500 ft in depth, had higher average primary and secondary recoveries than did deeper projects. Crude-oil gravity, which ranges from 20° to 45° API, was not relatable to yield of secondary recovery oil. Analysis of the data indicates that five-spot injection patterns will yield the highest percentage of oil remaining at start of flooding; that is, 28.8 pct for five-spot injection patterns, compared with 20.8 pct for line-drive patterns and 11.6 pct for random patterns. Waterflooding in this area appears to be very successful. Secondary recoveries of most projects are expected to nearly equal primary recoveries.

Jan 1, 1963