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By R. B. Moore

IN 1914 the writer and K. L. Kithil announced, through Bulletin 70 of the U. S. Bureau of Mines, that the United States possessed the largest deposits of radium-bearing ore in the world. At that time a small amount of this ore was being, mined and shipped to Europe, and one company was preparing to start the extraction and recovery of radium in this country. The importance of our carnotite deposits in Colorado and Utah up to the publication of Bulletin 70 was not, however, appreciated by anyone.. At that time the total supply of radium in the world was about 10 g., calculated as element, and when I estimated that at least 100 g. of radium element, and probably 200 g., would be produced from our carnotite deposits, there was a considerable amount of skepticism. Up to the present time almost 200 g. have come from this ore, and some writers put this figure a little higher. Uranium ore was found in the copper mines of the Union Minière du Haut-Katanga at Luiswishi in 1913. Later discoveries were made at other places in the Belgian Congo, and the Katanga ores now represent the largest supply of radium-bearing ore in the world. In fact, since 1923 very little radium has been produced from American carnotite, the Katanga ore representing practically the world's supply of. radium since that date.

Jan 1, 1930

By C. James, J. Siefke, D. Shumway

The Mojave Desert is a particularly fragile ecosystem that faces several significant impacts. These include rapid housing development, overdrafted water supplies, and loss of wildlife habitat as a result of mining, industrial activity and urban sprawl. Over the past three years, a diverse group of educators, natural resource managers and business leaders has been assembled under the auspices of a local college to provide unique natural resource education opportunities for the region. By leveraging the collective experience of these present generation natural resource professionals, the Mojave Sustainability Project hopes to provide the next generation of professionals with that knowledge and those technical skills upon which tomorrow’s community can rely. This paper is a case study of how partnerships between academia, government, industry and the community can serve to address the regional social, environmental, and economic needs of today, while investing in the development of those professionals who will balance these needs tomorrow.

Jan 1, 2005

By Carol Harrison

"Diseñar, implementar y evaluar un proceso de adquisición de tierras y reasentamiento ha sido un reto para los proyectos mineros en el pais, pues es un tema fundamental para el desarrollo del proyecto y reviste al mismo tiempo una alta complejidad en contextos sociales como el nuestro. Asimismo, no existe una reglamentación clara al respecto ni una institucionalidad que permita enmarcar el proceso, que al final resulta en una negociación directa entre dos partes. La presentación profundiza en ejemplos de experiencias de reasentamiento rural, particularmente en la definición y monitoreo de indicadores."

Sep 1, 2017

By Pedro Vargas Gálvez

El presente texto señala la metodología de selección del software de mantenimiento respecto a este mismo y a la Planta. Para ello, se detalla las condiciones que deberán considerarse en la Organización de Mantenimiento y la aplicación del Software de Mantenimiento MP2 a una empresa. Asimismo, se presenta el Plan de Implantación, los inconvenientes que se han encontrado así como los resultados obtenidos por la utilización del Software MP2.

May 25, 1998

By E. D. Gardner

This paper is the second of a series of three on placer mining in the western United States. The first paper4 discusses the history of placer mining in the Western States and the production of placer gold, geology of placer deposits, location of placer claims on public lands, sampling and estimation of gold placers, and classification of placer-mining methods, together with hand-shoveling and ground-sluicing. This paper deals with hydraulicking, sluice boxes and riffles, recovery of gold and platinum from placer concentrates, treatment of amalgam, and marketing of placer gold. The discussion of sluice boxes and subsequent subjects in this paper applies to all forms of placer mining. The third paper deals with dredging and other forms of mechanical handling of placer gravels, and drift mining.

Jan 1, 1934

By I. Ciabatti

Inorganic salts of hexavalent iron (ferrate (VI)) are versatile reagents for water and industrial effluent treatment because of the strong oxidising effect of the ferrate ion (FeO42-) and the well-known coagulation properties of the resulting ferric ion. Among other applications, ferrate can effectively remove arsenic, cyanide and phenols from industrial effluents. Furthermore, ferrate salts can be prepared from ferrous sulphate, a common byproduct of the steel and titanium industries, and possibly from other iron wastes. Notwithstanding their many potential advantages, the industrial-scale application of ferrate salts, such as potassium ferrate (K2FeO4), for effluent treatment has been hindered by the difficulties inherent in their synthesis and stabilisation. Within a project co-funded by the European Commission, the large-scale synthesis of stabilised potassium ferrate was realised through a new synthesis process, and different applications of the resulting ferrate to effluent and wastewater treatment are under investigation. This paper reports the results of the application of stabilised potassium ferrate for the purification of textile effluents. Laboratory and pilot-scale tests were carried out and the performance of the ferrate was compared to that of chemicals currently used in wastewater treatment. According to these experiments, potassium ferrate is a promising reagent for an effective treatment of textile and other industrial effluents.

Jan 1, 2006

By S. Paul Singh

Rock burst is one of the most serious mining hazards, adversely affecting the safety, economy and productivity of mines. It is a sudden manifestation of the release of strain energy stored in the rock mass. At present, there is no universally accepted method for predicting the timing of the rock burst. However, if the seismically hazardous regions in mines can be identified before they are exposed to mining then precautionary measures can be planned before the work begins. A study was conducted in Sudbury Nickel Belt and an approach has been proposed to identify rock burst prone workings on the basis of (a) Rock properties and bursting indices (b) In-situ approaches (c) Geological features (d) Mining conditions (e) Observations during mining operations (f) Comparison and analogy with previous case histories of bursting. This approach will facilitate the judicious application of the burst control techniques to seismically hazardous areas.

Jan 1, 2008

Future climate variability and change will impact on mining operations and their attendant communities. To minimise this impact, early and informed risk management is warranted. However, research into the risks posed by climate to the Australian mining industry has so far been limited. We are conducting a systematic study of the mining life-cycle to identify the main areas of vulnerability and adaptive capacity of operations and communities. This project aims to assess what adaptation activities are currently being undertaken within the mining industry and its communities across Australia and to develop a risk management approach that will aid the adaptation of practices in and around the industry, better assuring the security of people, jobs, revenue and the environment under changed or extreme climate conditions. The Canadian mining industry was recently assessed through a similar study, which found that many mining companies perceive a real risk to mining from climate change in the future, despite few companies being actively involved in managing such risk. At a workshop held by CSIRO involving mining specialists, the most vulnerable stage in the mining process in the Australian context was assessed to be production. In particular, impacts on water and energy supplies and also transport and infrastructure were of high concern. Additionally, heat stress on workers and equipment, changes in groundwater flow and increases in geohazards were also identified as important factors in the short and long term if problematic climate events become more extreme or more frequent. Risks in the planning and post-mine stages were also identified. Based on literature reviews and preliminary discussions with mining experts, here we present an initial assessment of the climate adaptation issues relating to mining and its associated communities and describe our future work plans in this area.

Jun 1, 2010

Pressure Oxidation of Sulfide Gold-Bearing Concentrates with Double Refractoriness

Sep 13, 2010

By Matthew P. Wickham

The use of existing mine records in conjunction with an appropriate classification scheme can be used successfully to identify and characterize the composition of existing waste rock facilities where traditional approaches based on sampling may be impractical or costly. This paper describes an alternative approach used in an acid rock drainage investigation at a porphyry copper mine with numerous waste rock dumps of varying ages and composition. The approach integrated detailed lithologic and mineralogic information about the ore body and overburden materials with records of pit development and dispatch. A waste rock characterization matrix was developed for the site to meaningfully classify lithology and mineralogic composition of the waste rock. The approach resulted in a focused geochemical testing program and facilitated interpretation and application of the test results.

May 1, 2002

Ten years ago we surveyed in "Uspekhi Khimii" the mechanism of the synthesis of hydrocarbons from CO and H2 (1).5 With new data obtained since then, mostly by Soviet researchers, our previous work (2), dealing with new forms and catalysts of the synthesis, is brought up to elate by reviewing research in this field. FORMATION OF CARBIDES The hypothesis that carbides are intermecliates in the synthesis assumes that carbon monoxide reacts with the metals of the eighth group and that this reaction is connected with the reversible reaction 2CO[=]C +CO2 (1) in a certain range of temperatures (3).

Jan 1, 1958

By D J. Williams, A K. Kho, A Shokouhi, N Tucker

The disposal of dewatered coalmine tailings and coarse reject within spoil piles is gaining popularity as a means of eliminating separate surface tailings storage facilities or dams. The contrasting characteristics of coalmine spoil, coarse reject and tailings are somewhat complimentary, making the co-disposal of dewatered tailings within spoil piles geotechnically feasible and environmentally attractive. However, the impacts of mixing plant rejects within spoil piles are not well understood; in particular, the effects of water draining from the mixed plant rejects on the moisture content of the surrounding spoil. Changes in moisture content can cause additional collapse and degradation settlements of the spoil pile. A series of laboratory tests has been undertaken on mixtures of dewatered coalmine tailings, coarse reject and spoil. The results of these tests have been incorporated into a spreadsheet-based settlement prediction tool to investigate the effects of incorporating mixed plant rejects on total spoil pile settlements. This paper presents the laboratory tests undertaken, the incorporation of the test data into the settlement prediction tool, and settlement estimates for the various mixtures at different stages of construction.CITATION:Kho, A K, Tucker, N, Williams, D J and Shokouhi, A, 2015. Impact of co-disposing mixed plant rejects on spoil pile settlements, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 51–62 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By A. Stawsky

Effective use of diesel vehicles in underground mining requires attention to improved control of diesel exhaust pollutants such as particulate (soot), oxides of nitrogen and sulfur and carbon monoxide. An experimental survey Is made of diesel emission aftertreatment control techniques including water scrubbers, catalytic converters, exhaust gas recirculation (EGR) and soot filters. Use of two or more techniques in combinations are tested for optimum control of all exhaust pollutants. Dynamometer data is developed for steady state and computer controlled simulated mines duty cycles operation of Deutz F6L-714 and F8L-413 engines. Exhaust Quality indices (EQIs) are calculated from dynamometer data for comparisons among the control combinations examined. The Corning diesel particulate filter (DPF) is shown to be the most promising and practical device. The Corning DPF in combination with EGR provided the best (lowest) EQI from the test data. Use of the DPF requires additional regeneration mechanisms such as a catalytic filter coating or fuel additives. A metal mine field test is made of DPFs on an operational scoop tram to test practical applicability. Further development is proposed for application to various mine conditions and for improvement of DPF regeneration techniques including coating with newly available catalysts.

Jan 1, 1987

By S. Bellec, P. Champagne, J. Châteauneuf, A. Berton, S. Fortier

"The start-up of new plants, extending from the commissioning of equipment to the production ramp-up, is a critical period where the processing circuit operation must be done in a structured and well controlled way to enable the gradual, safe and rapid achievement of production targets. The magnitude of the many risks associated with this pivotal period is accentuated in the actual context of low commodity prices. However, the implementation of a method that analyzes risks associated with a start-up, their probability of occurrence and their impacts leads to the identification of a series of preventive actions that can be applied in order to reduce potential negative impacts.Soutex has been involved in numerous start-ups over the last few years and has developed a structured methodology to assess this crucial period, maximize the pre-start-up preparation, ensure a smoother and safer ramp-up period and minimize the time needed before reaching commercial production.This paper describes a method to identify preventive actions to apply in order to reduce risks related to a plant start-up. Then, the various steps of the method are demonstrated using the industrial case study of the Canadian Malartic gold plant situated in Abitibi, Québec. The specific preventive actions, during start-up, the organisational measures and the ramp-up plan are detailed as they were effectively achieved. Finally, the post start-up actions are presented as well as some key results illustrating the achievement of their prior defined objectives.IntroductionPlanning a new plant or new circuit start-up in a mine installation involves various risks, both at the economical and safety levels. Unprepared staff and equipment can lead to safety issues that could threaten plant staff as well as the environment. Moreover, a poorly prepared start-up could often lead to equipment break-down, production stoppages and delays, leading to important economic impacts, delaying commercial production and therefore affecting directly the profitability of mining projects.It is common in the industry to have structured commissioning procedures for major equipment taken separately. Technical personnel from the equipment manufacturing company would usually come on site in order to perform the pre-operation verification, dry runs and the first hours of operations. This kind of assistance is usually focussed on one piece of equipment and neglects the interactions between the various equipment of the production chain. The commissioning phase is usually maintenance oriented and the information given by the manufacturing representative seldomly flows through the operation staff (in the case of this paper, the denomination “staff” refers to both managing and operating employees). The global process is usually not taken into consideration by the technical personnel sent on-site by the manufacturer during the commissioning phase. Many papers can be found describing the commissioning of new equipment focussing on the technology (Côté and Adante (2009), Wells et al (2007)) but without dealing with its integration process in the complete production chain."

Jan 1, 2016

By Nic Slatalla

Resin anchored rock bolts are an effective tool to control the deformation of an underground opening because they combine high support capacity with fast installation. However, there are still numerous shortcomings concerning the understanding and interaction of the system bolt-resin-rock. Field and laboratory test series have been conducted for evaluating the load capacity and bond strength of resin grouted rock bolts in different host rocks under axial load. This paper describes that the behavior and shear strength of the system bolt-resin-rock depends on the rock type and discusses a simple correlation between peak shear strength and shear stiffness in the ratio 1:1000 which may moreover be helpful for estimating rock bolt capacity after installation.

Jan 1, 2006

By Keith L. Harris

The U.S. economy continued to grow moderately in the third quarter, but at a slightly higher rate than in the previous quarter. According to the Department of Commerce's preliminary estimate, real gross national product (GNP) grew at a seasonally adjusted annual rate of 3.3% during the third quarter of 1985, compared with a revised 1.9% for the second quarter and 1.6% for the third quarter of 1984 (table 1). Civilian unemployment dropped from the constant 7.3% rate between February and July to 7.0% in August and 7.1% in September. Employment on nonagricultural payrolls continued to increase (table 2), resulting in a continued rise in personal income, which in turn supported growing consumer purchases. Although purchases of services continued to provide the underlying foundation for the economic growth, the manufacturing sector received additional stimulus from significant increases in consumer purchases of durable goods, particularly automobiles. The increased demand for durable goods resulted in significantly higher industrial production for August and September, compared with levels attained previously this year (table 3). Capacity utilization increased to 80.5% in August but returned to 80.2% in September, matching the 1985 low previously reached in July (table 4). The real net export deficit grew only $0.2 billion in the third quarter; at $34.0 billion, however, it continued to exert a negative influence on the economy. On September 22, in an effort to reduce the deficit and make U.S. goods more competitive on world markets, the U.S. Government agreed to cooperate with the Governments of France, the Federal Republic of Germany, Japan, and the United Kingdom in attempting to lower the-value of the dollar in relation to other world currencies. Low inventories, rising factory orders and construction spending, the possibility of a lower U.S. dollar, and aggressive automobile production plans announced by domestic producers for the fourth quarter indicate the potential for an increase in manufacturing activity in the United States.

Jan 1, 1985

By Nicolae Dobritoiu

The literature in this field and the practical activity record that a method, respectively the technology used for an underground mining work have many components which, in order to be applied, demand that for each of the parameters that describe the environment of the mining work and that influence the chosing of that method and that technology of execution, must have values in an interval well determined. There are situations when one or many parameters of the set of parameters that describe the environment of the mining work, can modify its values, and, as a result, one or more components of the methods or technology cannot be applied anymore, making necessary a replacement of their values. The information offered by this graphical-analytical model allow the determination of optimum solutions for the process of digging of the underground mining work and thus it will result the incresing of the technical-economical efficiency of the digging process and, also the increasing of the quality of the underground mining work.

Oct 1, 2009

By Nilabjendu Ghosh, Satyendra Kumar Singh, Gautam Banerjee, Harshit Agrawal

High-production methods like longwall mining with hydraulic powered supports are necessary to increase underground coal production in India. Longwall mining had a mixed success record for Indian geo-mining conditions. In this paper, an analysis is presented to optimally design an array of chain pillars in multi-seam longwall mining panels in the deepest coal mine in India. The study found that a chain pillar of 80-m width and 195-m length is necessary for long-term stability without any reinforcement. It was also observed that an optimum chain pillar can be designed by providing suitable side reinforcement (side bolting) which will reduce the chain pillar dimensions to 55-m width and 160-m length. Optimum design of chain pillars will reduce the coal locked up in these chain pillars by ~ 77%. This will also reduce the gestation period of longwall mining panel development. This paper also evaluates the maximum tensile subsidence strain induced at the surface and finds that the values are within the safe working limit of 3 mm/m. Thus, this paper finds direct application in the design of future multi-seam retreating longwall mining panels in Indian geo-mining conditions.

Laboratory-Scale Magnetohydrostatic Separator for High Resolution Density Analysis of Plastic and Other Wastes Recycling and reuse of different plastic wastes is still a current problem to solve for process engineers and it is true for seeking industrial applications as well as for smaller laboratory-scale, where a given waste sample, plastic or even metallic, has to be precisely separated into narrow density fractions to gain data for industrial design or for scientific research. The principle of magnetohydrostatic separators are known even there are industrial size machines but our primary aim was the development of a laboratory-scale separator for analysis of particles of densities up to 6 kg/L and sizes up to 8 mm. Main parts of the built experimental equipment are the ferrite core with two high power coils. The shape of the ferrite core at the two sides of the separator channel was specially designed to produce isodynamic magnetic field. In these places the ferrite core was constructed from laser cut ferrite sheets. The development of the high power electric supply for the two coils was a real challenge because the high voltage and current (400 V, 30 A) and because it had to be precisely regulated for being able to set discrete relative forces on the particles. Two separator channels were made from transparent plastic. The magnetic fluid is circulated by a centrifugal pump, fresh feed is supplied by a vibrated feeder and products can be taken by built in samplers. The velocity profile in the separator channel is measured by an ultrasonic Doppler velocity meter. Paper reports about the development and itself of the magnetohydrostatic separator and about some fundamental and applied laboratory experiments with different reference particles and wastes from used cars and electrical appliances.

Sep 13, 2010

By Steven J. Schatzel, Robert B. Krog

Frictional ignitions are defined as the ignition of a flammable mixture of methane and air that is initiated by frictional heating. Ignitions created through the addition of energy from open flames and exposed electrical circuits are not included in this analysis. Energy released in a roof fall that creates a spark and ignites a methane mixture would be considered a frictional ignition. Frictional ignitions represent the majority of all ignitions in underground coal mines. Over the study period of 1983 to 2005, a total of 1993 ignitions were reported in underground bituminous coal mines in the United States, of which 1589 were frictional ignitions. Reportable ignitions to the Mine Safety and Health Administration (MSHA) are any unintentional occurrences of flame underground regardless of duration. Frictional ignitions were reported in 155 mines and 13 states. Continuous miners represented the largest source for frictional ignitions with 1090 (68.6% of all frictional ignitions). Longwall mining operations represented the highest concentration of frictional ignitions during this study period with 1365 frictional ignitions (85.9% of all frictional ignitions). The 17 mines with the most frictional ignitions were all longwall mining operations and had 1130 frictional ignitions (307 from the shearer) that represented 71.1% of the total. In 1983, mines with frictional ignitions represented 6.9% of operating underground mines and 36.6% of total underground coal production. The percentage of operating underground mines with frictional ignitions and their total production has increased steadily and in 2005 represented 9.8% of active mines and 46.2% of underground coal production. The three coalbeds with the highest number of frictional ignitions (Blue Creek, Pittsburgh No 8, and Pocahontas No 3) had 1049 ignitions that represented 66.0% of all frictional ignitions. The three states with the highest number of frictional ignitions were Alabama (710), Virginia (247), and Pennsylvania (242) that represented 75.5% of the total. Frictional ignitions peaked in 1991 with a high of 114. In 2005, only 34 frictional ignitions were reported. If only frictional ignitions that occur at the face are considered, there have been no fatalities since 1983. Since this time, there were 33 ignitions that caused 53 workers to lose a total of 2912 working days. When including ground falls, then there have been four frictional ignitions with one incident causing two fatalities and injuring eight workers. From 1983-1991, underground productivity and the number of frictional ignitions increased. However, productivity continued to increase from 1991-2000 while total frictional ignitions fell, thereby disproving this connection between productivity and frequency of frictional ignitions. Ninety percent of all frictional ignitions occurred in underground coal mines that liberated more than 393 L/s (1.2 MMcfd million cubic feet per day) of methane through the main ventilation system. Although methane production is not the determining factor for the occurrence of frictional ignitions, it is a good indicator of the anticipated frequency.