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By Mustafa Onder

The paper point out that there are two méthods in the design of the long auxiliary ventilation systems. These methods can be summarized as constant fan spacing and constant fan size. If the fans are placed at the end of the duct, leakage will increase due to the high combined pressure.Also The program called SERIP can be used to examine the effects of positioning the fans at varying distances along the duct and determine the appropriate locations.

Jul 17, 2000

By M. L. Jeremic

Observations of ground behavior in mining the Choka Dulkan ore body have been described. Ore recovery was limited to approximately 60% because unconsolidated hydraulic fill did not permit either the widening of stope spans nor secondary ore recovery from pillars. Stope undercutting induced high stress concentrations. However, as extraction progressed, ground conditions improved but before extraction was complete they deteriorated again. After completion of a stope, the remnant rib and crown pillars continued to be deformed by other stresses for some time.

Jan 1, 1979

By D. Strachan

Installation of support in known poor ground intersections during reaming operations requires rapid access to stabilize the shaft wall and thus to prevent the loss of the shaft through scaling. This is especially relevant to shafts of long dimension where the duration from time of exposure to time of support installation is lengthy This paper deals with the innovative methodology employed at Harmony?s No. 8 Shaft 17/24 level sub ventilation shaft to rapidly support a shale intersection between 23 and 24 Level by employing a single deck stage suspended from the reamer head by means of Skyjack winches.

Jan 1, 2009

By E. Vilaescusa, J. Eloranta

The work presented in this paper investigates the influence of non-ideal detonation characteristics related to the blasthole diameter, base emulsion sensitivity (micro-balloon sensitised versus unsensitised) and percent emulsion on the explosive shock energy available to break rock using ANFOemulsion blends. A series of theoretical equal powder factor bench blasting patterns with hole diameters of 127mm (5”), 140mm (5.5”), 152mm (6”) and 165mm (6.5”) are compared to assess the non-ideal confined shock-state work energies. The Non-Ideal Shock Energy Factor (NSEF), which is the available shock energy per cubic meter of blasted material (MJ/m3) or kilocalories per cubic yard (kcal/yd3), is used to compare the different blasting patterns charged with a range of ANFO-emulsion blends from zero to 50% emulsion.

Jan 1, 2012

By G. Blackwell, E. Bozorgebrahimi

The trend in open pit mining has been to maintain cost competitiveness through economies of scale, particularly by implementing larger trucks and shovels. This paper considers the potential adverse impact of such scale adjustment, however, on dilution, maintenance, flexibility, and other aspects of operations. It examines the mine production characteristics affected by increased equipment size and attempts to quantify the impact on the overall operation. Reference is made to data from operations that have experienced a variety of equipment size ranges changes over the last decade.

Jan 1, 2003

By G. L. Smith

[Research and development conducted by CSR.-Mining Technology in the areas of active continuous miner based coal dust/methane explosion suppression systems, passive 'bag based, atone dust barriers systems, din and positioning of refuge bays, integrated escape and rescue strategies, and neural network based coal dust/methane explosion risk assessment is briefly described. It is concluded that effective catastrophic risk management of coal dust/methane explosions is dependent on an integrated, systems approach drat encompasses fundamental understanding of hazard sources, qualitative and quantitative probability of occurrence, magnitude of consequences and efficacy of control and recovery measures.]

Jan 1, 1999

By Dwayne K. Rowlett

A lysimeter designed to measure suction and collect a pore water sample from unsaturated waste rock has been developed and its performance has been verified in two large scale column tests. The test columns were constructed to bracket the envelope of grainsize curves for waste rock from Northern Saskatchewan. The suction profile within the columns was measured under a series of infiltration rates using tensiometers and these were compared to the lysimeter readings. The rate at which pore water samples could be collected was also measured under each infiltration rate. Lysimeter measurements of suction were found to be slightly lower than the tensiometers.

Jan 1, 2000

By Bert Allard, Åsa Sjöblom

The River Vormbäcken is the recipient of treated AMD from the Kristineberg mine site, northern Sweden, where mining of a complex sulfidic ore has taken place since 1940. Parts of the river flow through different kinds of wetlands. The changes in metal concentrations and water chemistry that occur upon passing these wetlands have been studied by analysis of water chemistry data from a number of stations along the river collected during 11 years of monthly sampling. It is concluded that the impact and functioning of wetlands cannot be elucidated from chemistry data alone. Future studies including e.g. reconstructed water flow are needed.

Jan 1, 2000

By Paul B. Queneau, Barry J. Hansen, D. Erik Spiller

Most lead and zinc secondaries are recycled pyrometallurgically. However, many problems encountered in secondary smelters have been solved by addition of physical concentration and/or hydrometallurgical processing steps, with resulting important environmental benefits. U.S. secondary lead and zinc operations are described, covering conventional smelters, EAF-dust treaters, and zinc sulfate/fertilizer producers, including plant capacities, technologies, and outputs. During the past two decades, remarkable advances have been achieved by recycling spent lead-acid battery components. Interaction between primary and secondary zinc producers, the fertilizer industry, and the zinc chemical industry has substantially decreased waste generation.

Jan 1, 1993

By Jarc H

The steeply dipping silver/lead/zinc orebodies at Mount Isa mine have been extracted most recently by a combination of cut-and-fill and open stoping methods. Bench stoping was first used at Mount Isa Mine seven years ago to allow safe extraction of a highly stressed cut-and-fill stope. Subsequent benches have shown that the method offers significant cost and safety benefits through increased productivity and reduction in man exposure. The success of benching has lead to cut-and-fill mining being replaced at Mount Isa.Significant resources have been focussed to optimise benching. This paper describes the operational, planning, and research and development aspects which have contributed to the method to date. A brief look is also taken at the future direction of benching at Mount Isa.

Jan 1, 1992

By E. J. Dorward-King, R. J. Kadeg, S. Pavlou

Risk assessment, risk management, and engineering/economic feasibility analysis are presented as three effective, practical tools for decision making in the remediation of contaminated soils. Risk assessment is applied to evaluate the extent, magnitude and sources of contamination, to identify appropriate contaminants of concern (COCs). Risk management is then applied to identify the acceptable contaminant residual levels for the COCs. Finally, engineering/economic feasibility analysis is used to define the appropriate cost-effective remedial action and associated target contaminant action levels that will achieve the acceptable contaminant residual levels. A real site application of this decision making approach is presented. This site illustrates that through appropriate engineering, acceptable risk-based contaminant residual levels can be achieved with higher action levels.

Jan 1, 1992

By Charles H. McGuirk

The movement of iron ore, limestone and-coal on the great lakes involves an intricate transportation network between mine, dock, vessel, railroad and consumer. The system requires that stockpiling be performed at certain points in the pipeline because of the seasonal closing of the lakes, traditionally, this has been accomplished at origin and destination with a substantial cost. Impact to both the shipper and consumer, From the time that the raw material is removed from the ground, expeditious handling and movement to final destination is threatened by a series of potential delays. An initial movement from mine or processing plant to the upper lake port must be coordinated between rail equipment and dock facility, As each vessel is loaded, a schedule must be developed which routes the cargo to an unoccupied lower lake port. However, if the vessel is not delayed by unpredictable weather conditions on the lake, the boat may still arrive at a port congested with other vessels awaiting their turn to unload.

Jan 1, 1973

By D. Parks, A. Miller, M. McNinch, R. Jacksha

Each year, hundreds of mine workers are involved in machinery-related accidents. Many of these accidents involve inadequate or improper use of lockout/tagout (LOTO) procedures. To mitigate the occurrence of these accidents, new safety methods are needed to monitor access to hazardous areas around operating machinery, improve documentation/monitoring of maintenance that requires shutdown of the machinery, and prevent unexpected startup or movement during machine maintenance activities. The National Institute for Occupational Safety and Health (NIOSH) is currently researching the application of Internet of Things (IoT) technologies to provide intelligent machine monitoring as part of a comprehensive LOTO program. This paper introduces NIOSH’s two phase implementation of an IoT-based intelligent machine monitoring system. Phase one is the installation of a proof-of-concept system at a concrete batch plant, while phase two involves scaling up the system to include additional sensors, more detailed safety/performance metrics, proximity detection, and predictive failure analysis.

By Lon D. Santis

This paper summarizes explosives transportation incident and accident data collected by the U.S. Department of Transportation (DOT) from 1993 to 1998. The paper briefly describes the legislation and regulations that cover hazardous materials transportation. The multimodal incident data collected by the Research and Special Programs Administration (RSPA) contained 86 incidents involving Class 1 materials during transit. Thirty-two occurred on public highways. The Federal Highway Administration (FHWA) data showed there were 8 1 motor-vehicle accidents involving explosives. The FHWA Crash datafile extract contained 649 records categorized as involving Class 1 materials although closer analysis revealed that nearly 90% of these did not involve explosives. In both databases, there were no fatalities caused by the explosive materials although 7 fatalities were the result of injuries suffered during the motorvehicle accident. There were also no serious explosions during any of these incidents or accidents. The paper concludes with an analysis of the risk involved with transportation of commercial Class 1 materials on the highway.

Jan 1, 2000

By Tilley J. L, Chicu D

The development of the Yallourn East Field brown coal open cut has involved the adoption of novel investigational programs into coal qual- ity. For example, weighted average coal property statistics for key proper- ties are determined by using a unique blend of traditional and 3-dimensional geostatistical estimation. Predicted property values are made freely available from the mainframe computer in the form of kriged esti- mates of 60 000 tonne coal blocks. Geostatistical predictions are being incorporated within the Mincom/Intergraph CADD system which is used for mine design. Key properties relating to coal type, moisture, and ash have been evalu- ated to provide the required data for the design and operation of both the open cut and the power stations as well as the briquette plant.

Jan 1, 1989

By K. Shen, A. J. Sinclair, N. Champigny

"Fluid inclusion studies from the Cinola deposit indicate low salinities and low C01 contents of the ore fluid. This supports a suggestion that the mineralizing fluids originated from pore water in the fluviatile host rock (mid-Miocene Skonun Formation). Bimodal distribution of filling temperatures suggests the existence of at least two temperature regimes centred on 160°C and 270°C during mineral deposition. Independent age and stratigraphic evidence indicates that depth of mineralization is between 1.1 and 1. 8 km, corresponding to a hydrostatic load of between 110 and 170 bars.RESUMELes donnees sur les inclusions fluides du gisement Cinola indiquent de basses salinites et basses teneurs en C01 . Ceci confirme que les fluides mineralisants ont ete derives de l'eau interstitielle prise dans les sedimentsfluviatiles hates. La distribution bimodale des temperatures d'homogenisation implique !'existence de deux regimes de temperature concentrees vers 160°C et 270°C pendant Ia mineralisation. La profondeur alaquelle le gisement s'est forme est evaluee d'etre entre 1.1 et 1.8 km a partir d'informations stratigraphiques independantes: ceci correspond a des pressions hydrostatiques de 110 a 170 bars."

Jan 1, 1982

By Tang Chaobo

According to the principles of simultaneous chemical equilibrium and electronic charge neutrality, the system of Mg(II)-NH3-CO32--SO42--H2O at 25°C has been thermodynamically analyzed. And the rule of solubility of MgCO3(s) in the system is discovered, the high dissolution field of MgCO3(s) is discovered too. Furthermore, the solubility of MgCO3(s) is increased with the increase of the concentration of SO42-, but it is decreased first then increased with the increase of the concentration of all the CO32- and the total concentration of ammonia and ammonium, and decreased with the value of pH being higher. Those results will has important significance on prepare magnesium chemical products and other salts carbonate that are strict with the content of magnesium with carburization method.

Jan 1, 2006

By A. Davis, K. Nelson, C. Webb

Abandoned mines in parts of the Black Hills of South Dakota have the potential for acid rock drainage. For this work, ten sites were examined on Black Hills National Forest land or on private land whose drainage could affect Forest Service land. Water samples from all the sites had pH values less than 6. Results of analyses from water samples and rock samples showed a correlation between metals content and pH. Acid-base accounting was used to determine acid drainage potential of the sites. One site (King of the West Mine) had a high potential for acid generation; fortunately, little or no surface runoff leaves the mine site. Six sites appeared to have moderate potential, including the Minnesota Ridge Mine, which currently is being remediated. Three of the sites had low acid drainage potential.

Jan 1, 2004

By Liuming Wu, Willis Forsling

The complexation of Alizarin Red S (ARS) at the surface of hydrous fluorapatite particles has been investigated at 25.0 C by means of potentiometric titrations, adsorption experiments in 0.1 M NaCI ionic medium, and Diffuse Reflectance Infrared Fourier Transform spectroscopy (DRIFT) studies. A chemical model describing the reaction at the aqueous mineral surface has been established under equilibrium conditions according to the reaction [== -CaOH2 + HA2 - « _ =PO CaA2 - z + H30&apos;; to (int.) = -5.61 ± 0.02 3 a =PO- logBs-1110(int.) ( ) within the range 8.40 <_ -log[H ] <_ 9.80.] Experimental data were evaluated using the computer program FITEQL on the basis of a constant capacitance model for the electric double layer. The surface complex structure, has been proposed to involve the quinoid and alpha phenolic oxygens of ARS coordinated to the calcium sites on the fluorapatite surface.

Jan 1, 1993

By D. Fourie

A brief history of channel sampling in South African gold mines is followed by a chronicle of different sampling events and sampling methods that used the traditional ?hammer and chisel? approach as well as diamond core extraction of the sample. The problems associated with each method of sample collection are documented and the use of a laser scanner to measure the exact volumes of sample material extracted from a correctly delimited sample site are considered. Areas where increment delimitation errors (IDEs), increment extraction errors (IEEs), increment weighting errors (IWEs), and increment preparation errors (IPEs) occur were investigated. A ?simulated chip sample model? is introduced and provides the basis for comparing the percentages of error introduced as a result of improper sampling. The heterogeneity experiment showed that reefs that are more homogenous tend have lower extraction errors than the more complex carbon-rich reefs, which may contribute to understanding the poor mine call factor on mines exploiting the latter types of reef. Keywords channel sampling, chip sampling, error, bias, modelling.

Jan 1, 2014