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By Jena Moshen

Underground Bulk Systems (UBS) technology has gained widespread application in tunneling and underground mining owing to its safety, reliability, increased Velocity of Detonation (VOD) and excellent results. However, its application in perimeter blasting is still limited and researchers are looking at ways of harnessing this technology for perimeter control. This simplifies the charging process by using one cost efficient product for charging both the perimeter and grid holes. This paper presents a case study on the application of underground bulk emulsion explosives for perimeter control blasting in underground room and pillar platinum mines. In order to achieve the required coupling ratios in the perimeter holes, the emulsion is loaded into specially formulated smaller diameter polyethylene (poly) pipes. The effectiveness of this method was evaluated using information obtained during routine blast audits and data supplied by the mines on half cast factors, over break and under break as well as analysis of data from Ground Penetrating Radar (GPR) Scans over a period of four years. This method of perimeter control, has given the platinum miners in Zimbabwe a competitive edge in cost effective perimeter charging and blasting by simplifying the previously costly deployment of traditional barrels and other decoupled cartridges. The method has been adopted by all the platinum mines in Zimbabwe as it has proven to be a cost effective alternative of controlling the perimeter walls, along with other key benefits that relate to safety, productivity and effectiveness.

Jan 1, 2018

By A. Basçetin

Equipment selection in mining engineering is one of the most important decisions that affects the mine design, production planning and economic parameters in open pit and underground mining. Mine planning engineers generally use their intuition and experiences in decision making. Mostly, linguistic variables (the weather is raining, soil is wet, etc.) come into question and decision-makers may not know how these variables are computed. Since the advent of the fuzzy set theory, these uncertainties are easily interpreted in the decision-making process. The development of computer technology and programming of colloquial language with expert systems have considerably reduced decision-makers? burden. This paper reviews the development of a computer programme software called EQS (EQuipment Selection) that automates equipment selection in mining engineering using fuzzy set theory. The EQS with an introduction of the concepts and theories of multiple attribute decision-making, the fuzzy set theory, and EQS applications to mining industry problems with case studies are presented

Jan 1, 2006

The common approach of designing blasts on a trial and error basis is quickly coming to an end. When utilizing the full scale blast environment, trial and error can quickly become cost prohibitive and leaves much to be desired in terms of true blast diagnostics. In these situations testing is usually only continued until a perceived improvement is achieved and when the gross undesirables in blast results are removed. This does not preclude, however, that further improvements of up to 100% or more can not be obtained.

Jan 1, 1994

By G. J. Colaizzi

The Bureau of Mines, at the request of local authorities in Rock Springs, Wyo., investigated and conducted through contracts a multistage program of exploratory drilling and pumped-slurry backfilling of 15 areas of potential subsidence in abandoned mine workings underneath that community. Initially, the Bureau in 1969 had recommended a program of gravity blind flushing of some of the inaccessible mine voids, and in 1970 a new technique, the pumped-slurry injection process, was tested for the first time in a site adjacent to the city's area of severe surface subsidence. Success of this initial testing program, and of a large-scale project in Scranton, Pa., led to further large- scale projects, funded by Congress, that resulted in the successful back- filling not only of all 15 target areas of potential subsidence in Rock Springs, but also of several areas in other States. Total cost of the projects in Rock Springs, including the original pumped-slurry test, was $3,243,993. A total of about 923,000 tons of sand was injected hydraulically into mine voids, rendering 178 acres of residential and central-downtown areas of Rock Springs less susceptible to subsidence damage. The pumped-slurry method was proved to be much superior to the gravity blind flushing method in term of the amount of solids that could be injected underground through a single borehole. However, there are special conditions that make this technique more or less applicable in different areas or underground configurations, as noted in the report's conclusions.

Jan 1, 1980

Geotechnical input is interwoven into the mining process at George Fisher South Mine from the planning and design of working areas to the closure of worked out areas and maintenance of life of mine and long term excavations. The methodology used consists of a mixture of application of established theoretical principles and guidelines derived from successful historical experience. In the development stage, including long term infrastructure excavations, the process takes into account the expected life of the excavation, usage and expected stress changes during its life span. On the stoping stage, the design process takes into account the local rock mass conditions, geological structure setting and previous experience in a particular orebody. Due to the high variation in age of currently used excavations, a rolling monitoring and risk assessment process for long term and life of mine excavations and infrastructure is maintained. This paper has as an output the process that must be followed to ensure an excavation on the highly dynamic mining environment at George Fisher South Mine is blasted and maintained in compliance with applicably commonly accepted safety and industry requirements.

Nov 25, 2010

By J. C. Haptonstall

The Bismark Mine is located in northern Chihuahua, Mexico, 150 km (95 miles) southwest of Ciudad Juarez (Fig.1). The ore deposit was discovered in 1979 and was placed in production in 1992. The production rate is about 2.4 kt/d (2650 stpd) from an ore reserve of 8.5 Mt (9.3 million st). Grades currently average about 8% zinc, 0.5% lead, 0.2% copper and 50 g/t (1.46 oz/st) silver. Substantial inflows of water into the underground mine complicate the operation. Complex metallurgy poses another challenge for the operators. Bismark is a joint venture with 90% participation by Minas Penoles, SA de CR of Mexico City and 10% participation by Promociones Industriales Banamex, S A de C V (PIB S A) of Mexico City. Anew company, Minera Bismark, SA de CV was formed to operate the property. Cyprus Minerals was a 40% participant in the joint venture but, in early 1993, sold its share to Minas Penoles. The Bismark Mine is one of the largest new underground mining projects built in Mexico during the last 10 years. It is the country's fifth largest underground metal mine and provides about 1 % of the world's zinc supply at about 50 t/a (55,000 stpy). Bismark is a trackless operation with overall productivities of 7.6 t/manshift (8.4 st/manshift). The 2.4-kt/d (2650-stpd) concentrator started up in March 1992.

Jan 1, 1994

Deposits of the Reefton Goldfield, West Coast, New Zealand, are hosted on N-NE striking, upright folds of the Greenland Group. High-grade quartz lodes are hosted on axial planar shears, typically have short strike lengths, and form shoots that pitch steeply on the hosting shears. Deposits within the field area of a detailed structural study share these characteristics. Field mapping and microstructural analysis have demonstrated that the Greenland Group was affected by a multideformational sequence. Gold mineralisation is hosted on shears axial planar to the F2 folds, but occurred during a subsequent deformation event (D4). Deformation during D4 resulted from N-NE directed shortening, near parallel to the trend of the F2 folds. This event produced F4 kink folds that were accommodated by layer parallel slip on S2 parallel shears, gold mineralisation during D4 being confined to the dilational hinges of F4 kink folds. The semi-brittle nature of D4 allowed the formation of stockwork veining and disseminated mineralisation within the F4 hinge zones. Most deposits within the goldfield are similar to those within the field area, and are interpreted to have been mineralised during D4. The two largest known deposits within the goldfield, however, are distinct. The Blackwater Deposit, striking parallel to the hosting folds, has a combined strike length of 1 km. The Globe-Progress Deposit is hosted on an E-W striking discordant shear in which a brittle zone of disseminated mineralisation encompasses high-grade quartz lodes. The characteristics that distiguish the Globe and Blackwater deposits may be due to formation before and after D4 respectively. Detailed field mapping in the vicinity of known deposits throughout the goldfield will further refine the relationships between the F2 folds, later deformations and the localisation of ore deposits. Additional mapping may also help constrain the position, orientation and extent of additional orebodies.

Jan 1, 2001

This paper discusses the impacts that advances in metallurgy and process engineering have on minerals project execution. Ausenco's business is focused on integrating minerals processing technology and the delivery of cost effective processing plants that exceed client performance expectations. The metallurgical development is a small but critical part of this process. Metallurgical development and innovation outcomes need to be transformed into an engineered solution and that solution converted into an operating plant in a cost conscious and competitive environment. Including new or innovative processes in a project flow sheet increases a project's technical and commercial risk. However, it also gives the project, and/or the engineering company, a potential advantage over projects using mainline practices. Managing the balance between risk and opportunity has been a cornerstone of Ausenco's success in recent years. Some advances in "technology" that are discussed in the paper include: larger capacity equipment new flow sheet concepts simplification of process interfaces, and more effective project strategies The common theme is that having a new idea can be the easy bit, putting it into operation effectively involves numerous people, many interfaces and strong project management.

Sep 13, 2010

1974 The Society of Explosives Engineers officially formed to “advance the art and science of explosives engineering” on August 20, 1974 in Pittsburgh, Pennsylvania.

Jan 1, 2010

By H. A. Domian, H. Biloni, G. F. Bolling

Jan 1, 1965

By Kevin Malone

Mercury, or quicksilver as it is often called, has many applications in modern technology. Used principally in electrical apparatus, industrial contol instruments, insecticides and fungicides, electrolytic preparation of chlorine and caustic soda, chemical processes, pharmaceuticals, and dental preparations, the liquid metal has unusual properties that make it a preferred material for many industrial uses. United States consumption of mercury during the past 40 years shows a rising trend. In all except 4 years, U.S. production has been less than the domestic requirement, and imports, principally from Spain, Italy, and Mexico, have supplied most of the deficit. After World War II, domestic output decreased rapidly until 1950, when it was the lowest in the 100 years covered by production records. Higher mercury prices since 1950 have reversed the decline in domestic output and reduced the gap between U.S. production and consumption. Domestic output in 1958 was the highest in peacetime since 1883; however, the nation still imported 28 percent of its mercury requirements from 1950 to 1960 the price of mercury was high as a result of industrial applications of the mercury cell, the impact of the cold war and the Korean war, and the Government stockpiling program. The stockpiling program, in effect, put a floor under mercury prices even though only 9,428 flasks of domestic mercury went into the stockpile under the original program which ran from July 1954 to December 31, 1957. Under an extension of the program, an additional 17,463 flasks was purchased.

Jan 1, 1962

By S. H. Lorain

This paper is one of a series being published by the Bureau of Mines describing the mines and mills and subjects related to mining in western mineral areas. Although mining districts in the Tobacco Root Mountains are numerous there is a strong similarity in the character of the ore deposits and in the climatic and economic conditions affecting mining throughout the region. Individual mines are small, but the production of lode mines

Jan 1, 1937

By Dennis Molvik, Omar Fulton, Chris D. Breeds, Don Gonzales

This paper presents and describes the South Interceptor Parallel Phase III Contract C93012C, which involved construction of a nominal 2.7 m (9-ft) finished diameter sewer conveyance using both pipe jacking and conventional tunneling methods. Earth Pressure Balance (EPB) excavation was required to minimize the potential for settlement beneath a main rail line, overpass, sensitive wetland, areas of contaminated soils, and nearby structures. Ground conditions predicted in the Geotechnical Baseline Report included low plasticity, clayey silt (40 to 10%) and silty sand (60–90%) with pieces of wood such as logs, stumps, branches and other tree fragments. Soil cover ranged from 2.7 m (9-ft) to 5.4 m (18-ft) over the tunnel crown with a groundwater table between 1.5 m (5-ft) and 3.7 m (12-ft) deep.

Jan 1, 2003

The development of a noise attenuated compressed air driven fan is described. The fan, which employs the jet reaction principle, possesses blade extension pieces which penetrate into an acoustically treated annular chamber. The dominant noise source, namely the air jets, is thereby partially suppressed. In addition, the increased moment arm of the jets leads to an improved propulsion effect which contributes to the improved aerodynamic performance of the unit.A typical measure of the improvement of this type of auxiliary mine ventilation unit is a 4 per cent increase in efficiency and a 10 dB (A) drop in sound level for a fan duty of 0·5 kPa and 1600 litre/s. This degree ofattenuation corresponds to at least halving the loudness level, a subjective noise measure.

Jan 1, 1973

The influence of varying amounts of magnesia, silica, and alumina in iron ore sinter on its mineralogy, reducibility index (RI), reduction disintegration index (RDI), physical breakdown (AI and TI), and production properties (coke breeze rate) were examined. It was found that the mineralogy of iron sinter can more easily be predicted from its chemical composition than from the RI, RDI, AI or TI. Anticipating the consequence that varying amounts of MgO and SiO2would have on sinter properties is complex, and not necessarily predictable. High concentrations of Al2O3in the sinter result in high concentrations of the SFCA phase, but with drastically deteriorated properties. This study also confirmed that the form in which fluxes are added to the raw material sinter mixture affects the mineralogy and properties of the produced sinter.

Jan 1, 2010

By S. K. Murphy, S. M. Spottiswoode, A. M. Milev, D. Geyser

A portable, stand-alone instrument especially designed for recording strong ground motion was used in this study to create a large database of peak particle velocities measured underground. A total number of 39 sites located in stopes mining Carbon Leader and Ventersdorp Contact Reefs were investigated. Peak particle velocities whith values up to 3 m/s were recorded at some sites. The data recorded on the skin of the excavations were compared to the data recorded by the mine seismic networks to determine the site response. The maximum site response was obtained for source radii of between 5 m and 30 m and events locating within 200 m of the site. The extreme values of peak particle velocities were obtained in cases were the face-area lay within the source radius. Un instrument portable unique spécifiquement conçu pour enregistrer les mouvements dynamiques des terrains, a été utilisé dans cette étude pour créer une base de données importante sur la vélocité maximum des particules, mesurée en souterrain. Un nombre total de 39 sites situés dans les excavations exploitant les récifs appelés ‘Carbon Leader et Ventersdorp Contact Reefs’, a été investigué. Une vélocité maximale avec des valeurs allant jusqu’ à 3 m/s a été enregistrée sur certains sites. Les données enregistrées sur le bord de l’excavation ont été comparées aux données enregistrées par les réseaux séismiques de la mine pour déterminer la réponse du site. La réponse maximum du site a été obtenue pour des sources de rayons entre 5 m et 30 m et des évènements situés dans les 200 m du site. Les valeurs extrêmes de vélocités maximales ont été obtenues pour les cas où la zone de face se trouve à l’intérieur du rayon de la source. Ein mobiles, alleinstehendes Instrument, speziell entworfen um starke Formationsbewegungen aufzuzeichnen, wurde in dieser Studie verwendet um eine große Datenbank von Partikelspitzengeschwindigkeiten, die Untertage gemessen wurden, aufzuzeichnen. Eine Gesamtanzahl von 39 Aufstellungsorten in den Schichtabbauorten vom Carbon Leader und Ventersdorp Contact Reef wurden untersucht. Partikelspitzengeschwindigkeiten mit Werten bis zu 3 m/s wurden an einigen Standorten aufgezeichnet Die an der Oberfläche des Grubenraumes aufgezeichneten Daten wurden mit jenen Daten verglichen, die vom seismischen Netzwerk der Grube notiert wurden, um die örtliche Reaktion des Standortes zu bestimmen. Die maximale Standortreaktion wurde für Ursprungsradien von zwischen 5 m und 30 m erhalten und Ereignissen die sich innerhalb von 200 m vom Standort befanden. Die extremen Werte der Partikelhöchstgeschwindigkeiten wurdenin jenen Fällen erreicht wo sich der Abbaubereich innerhalb des Ursprungsradiuses befand.

Jan 1, 2003

By John R. McWilliams

This is one of a series of reports being published by the Bureau of Mines on mining methods and costs at various mines throughout the United States. Including the Holden mine in this series is particularly appropriate at this time. The mine was operated on a low-cost, large-scale production basis to compensate for low-grade ore. Even with the best conditions and the most efficient methods, the margin of profit was small. Under the present situation of rising costs and lowering metal prices, the profit margin vanished. On June 28, 1957, the mine operations ceased; therefore, this report can review the entire life span of the mine.

Jan 1, 1958

By Rob Stewart

Acknowledgements ? Josef Macek(Manitoba Geological Services) ? Sally Goodman (SRK) ? Inco Geologists ? Rogerio Montiero ? Thompson Mine Geologists Introduction ? Regional Geology ? Thompson Geology ? Stratigraphy ? Sulphide Characteristics ? Conceptual Model ? Structural History ? Belt ? Thompson Mine ? 1D Deposit ? Ore Controlling Structures ? Using Structural Data to Guide Exploration ? Summary

May 1, 2006

By Daniel Saint Don, Jacques Dumouchel

QIT Madagascar Minerals (QMM)’s heavy mineral sand deposit located near the Village of Fort Dauphin, Madagascar was recently drilled using Boart Longyear Company’s Mini-Sonic drill. Continuous sand core samples were obtained to a depth of up to 30 meters for analysis and compared with the existing drilling data. Results were used as part of a validation process of the resource estimate, based on approximately 1,500 exploration holes drilled to date.

Jan 1, 2005

Jan 1, 1969