Search Documents

By S. D. A. Hannot, H. Knapp

"High pressure grinding rolls (HPGR’s) are an energy efficient solution for comminution of industrial minerals and metal ores. The technology is successfully applied in an expanding field of applications throughout the minerals industry. HPGR’s compress and grind the particle bed in the operating gap between two counter-rotating rolls. The equipment provides a high capacity, low energy alternative for applications with conventional tertiary and quaternary crushing and grinding, with size reduction reaching from 100mm down to 25 microns product. In this process, maintaining a controlled and evenly distributed operating pressure between the rolls is very important. Due to feed segregation, the pressure distribution along the roll’s length can become uneven, resulting in a coarser product. This paper will show that the best approach to compensate and adapt for the uneven pressure is to allow the rolls to skew relative to each other. Coarser products are also caused by an inadequate pressure distribution: the much-discussed edge effect. To minimise the consequence of the edge effect, an optimised ratio for the roll length to diameter will be calculated. Furthermore, the design philosophy behind a cheek plate will be detailed. This cheek plate is used to retain the material between the rolls, reducing the edge effect while still allowing roll skew. Together these design considerations help optimise HPGR’s performance.INTRODUCTION Initially developed for the cement industry during the energy crisis in the 1980’s , high pressure grinding has been an accepted technology for many years. It has been successfully implemented throughout the minerals industry, with applications in base and precious metals, as well as industrial minerals processing. The comminution process relies mainly on size reduction through to compression and inter-particle crushing in a particle bed in the operating gap between two counter-rotating rolls. The equipment typically has a high unit capacity and low energy consumption, and is increasingly used as an alternative to conventional tertiary and quaternary crushing and grinding, in particle size ranges reaching from 100mm down to 25 microns. It can be applied to moist ores and dry material, in open circuit arrangement or in a closed circuit with dry or wet classification (screening, air classification)."

Jan 1, 2019

By J. Clark

Erosion control during the mining cycle can be more effectively planned using Erosion and Sedimentation Control Plans (ESCPs). This raises the issue of who should develop an Erosion and Sedimentation Control Plan Guidance document (ESCPG) to standardize the content of ESCPs. A search for ESCPG documents in Canada revealed no examples for mine sites. In the U.S. there are a number of regulatory authorities who developed such documents for mine sites, including EPA. An ESCPG is expected to result in: (a) plans will be more standardized (b) more clarity and efficiency for those generating ESCPs; (c) assisting regulators tasked with reviewing/approving ESCPs; (d) providing guidance for the mine effluent permitting process relative to sediment control; (e) providing a basis for developing and including ESCPs in the Environmental Assessment (EA) phase and the mine economic assessment; (f) applying and optimizing ESCPs above the ?watersheds? of sediment ponds; (g) utilizing the ESCPG document for ?exploration? sites; (h) lowering the risk of adversely impacting water quality downstream of mining activities; (i) providing a methodology for determining the need for sedimentation pond(s) during the construction and production phases; and (j) providing a clear environmental sustainability message relative to sediment control if the mining industry takes the lead in developing an ESCPG. ESCPs will proactively create increased administrative (regulatory) efficiency in the EA and sub-EA reviews relative to erosion control and sediment release from mine sites. This also assists the new initiative in BC, One Project, One Process (OPOP) and synchronous permitting (a variation of concurrent permitting): as an example, enhanced erosion control planning at the EA phase then allows the synchronous permitting initiative to proceed efficiently, particularly for the mine permit (Ministry of Energy, Mines and Natural Gas) and effluent permit (Ministry of Environment). Approximately twenty more management plans (e.g. ARD/ML, explosive management, emergency response, hazardous waste, sediment pond operation, environmental effects, environmental sampling, etc.) may also be entered into the EA process to create increased efficiency, and then feed into the synchronous permitting effort. The BC OPOP initiative also adds support to the Canadian Federal ?One Project, One Review Process? approach. The ESCP and a sediment pond management plan will also address the Canadian Metal Mining Effluent Regulations requirement for all discharges from mine sites to meet a grab sample of 30 mg/L Total Suspended Solids.

Aug 1, 2013

By S. E. Kesler, C. M. Moore, J. C. Van Loon

The possibility that chlorine and fluorine form complexes with ore metals, thereby having a strong effect on the mobility of these ore metals during late magmatic and hydrothermal processes, suggests that the abundance of chlorine and fluorine in igneous rocks could be used to distinguish intrusions that have generated ore deposits. The simplest and most economical measure of this chlorine and fluorine is the water-leachable chloride and fluoride that is released from fluid inclusions in the rock during crushing of the sample. In order to evaluate the possible use of this technique, measurements of water-leachable chloride and fluoride were made with selective ion electrodes on samples from nine intrusive complexes. There does not appear to be any simple relation between the abundance of chloride and the presence of mineralization. Fluoride values in mineralized intrusions appear to be higher than those in barren intrusions.

Jan 1, 1973

By A. Kowalski

This paper presents methods of implementation and the added value that can be achieved by connecting personnel tracking systems and alarm-broadcasting systems. The authors point out the functions of the two systems that enable cooperation between them. Methods for connecting the systems on the surface and underground areas of mines require some intervention in both systems, so the authors point out a possible phased approach to introducing cooperation methods. Due to the fact that tracking systems in Polish mines are at an early stage of implementation, the article aims to provide new functionality, attempts to identify the needs of future users, and describes the experience of both production companies in terms of the development of cooperation methods.

Aug 1, 2013

By W G. Forbes

SOME 20 years ago, upon finishing second year at the University of Manitoba, I was faced with the choice of whether I wanted to be a geologist or a chemist. Accordingly, I sought out Professor Brownell, Head of the Department of Geology, to ask him what a geologist did. His reply contained the statement that following graduation one went out into the field in northern Canada for 5 to 15 years to reduce to practice what had been learned at university. To a young man, very socially conscious, even one year, let alone 5 to 10, in a small mining community sounded like being banished to a monastery in the Himalayas and thus I turned to chemistry. Moving to the present, last month I asked a geologist, and then a mining engineer, what does the fresh graduate in their field do these days? The reply was: usually serve an apprenticeship for an indeterminate period either underground or in the field learning the job.

Jan 1, 1965

By L. Tong

"The oxidation of Quebracho was evaluated by acid-butanol assay, which indicates depolymerization of Quebracho. Anthocyanidin, an oxidation product of Quebracho, is stable at 95?C for up to 2 h. The ionization, complexation, and oxidation properties of Quebracho were discussed. Complexation of metal-Quebracho occurs at ambient temperature. The formation of complex precipitates is influenced by the acidity of the solution. Temperature is another important parameter that influences the oxidation and the complexation of Quebracho. Quebracho-ferric complex precipitate forms at 90?C, 0.1 mol/L H2SO4. The formation of Quebracho-metal complex in the leach solution is a possible reason for the consumption of Quebracho. Quebracho molecules adsorption on the mineral surface is reduced by consumption of Quebracho, resulting in poor sulfur dispersing effect in the leaching process. INTRODUCTIONQuebracho is used as a sulfur dispersing agent (SDA) in the pressure leaching of zinc concentrate as stated in U.S. Patent No. 3,867,268 (1975). It prevents the zinc sulfide particles from being coated with molten sulfur, thus preventing the inhibition of the zinc leaching reaction. Recently, the sulfur dispersing effect of Quebracho was investigated in the oxygen pressure leaching of nickel concentrate. The oxygen pressure leaching of pentlandite can be represented by reactions 1-3."

Jan 1, 2012

By T. Newton, G. A. Bezuidenhout, P. J. Tauetsile, F. Trask

The technology to selectively leach gold, silver and base metals from ores, concentrates, and wastes, using an alkaline glycine solution, has initiated significant interest in using the new technology in various environments such as in-situ, in-place, dump, heap, and vat and agitated tank leaching. It has been shown that glycine acts synergistically with a number of other lixiviants to lower the net consumption of the other lixiviants while allowing low cost glycine solution recovery. Glycine is a non-toxic, stable, environmentally benign reagent that is available in bulk industrial quantities. It has the ability to dissolve most copper oxide and sulfide minerals, as well as native copper, whilst not interacting with acid consuming gangue nor dissolving iron and various or ubiquitous gangue elements. It acts synergistically with small amounts of cyanide to leach gold-copper ores at leach rates higher than either glycine or cyanide on their own, while significantly reducing cyanide consumption and eliminating detoxification requirements. The leaching behaviour of various glycine based systems will be reviewed, followed by the evaluation of the adsorption of gold onto activated carbon. Where the economics merit it, copper can be easily recovered using solvent extraction or sulfide precipitation.

Jan 1, 2017

By K. Shitogiden, Y. Samada, T. Miki

Steelmaking slag contains nutrition such as Si, P and Fe for acceleration of phytoplankton growth. Phytoplankton can fixate carbon dioxide more than any other species on earth. Hence, suppression of CO2 can be achieved by applying the potential of steelmaking slag as the nutrition for their propagation. When it is considered to supply nutrition from steelmaking slag to seawater, we must avoid dissolution of hazardous elements or change of pH of seawater by steelmaking slag addition into seawater. The protection against dissolution of fluorine into artificial seawater has been studied based on dissolution behavior of steelmaking slag and synthesized substances into artificial seawater in the present work. The dissolution mechanism of fluorine from steelmaking slag and buffering action of pH change are discussed by using stability diagram in seawater.

Jan 1, 2004

By A. E. Cameron

The theory of atomic distribution of the stranger atoms in the space lattice of the solvent metal has been well developed by Rosenhain. It has long been known that the addition of one metal to another to form a solid solution increases the strength and hardness of the solvent metal. This increase is practically proportional to the amount of added substance up to the limit of solid solubility. To account for this increase in hardness and strength, Rosenhain assumes that the stranger atoms occupy positions on the solvent metal space lattice. Atomic attractions about the stranger atoms will not be the same as in the case of the pure metal, and there will thus be a disturbance of the orderly arrangement of the atoms on the space lattice, or a distortion of the lattice. Such a disturbance would interfere with the ease of slip along the planes and would thus tend to promote strength and hardness. Rosenhain notes that not only may there be a local disturbance of the lattice about the stranger atom but there may well be also a measurable change in the dimensions of the lattice as a whole. The relative amounts of local and general distortion of the lattice will depend upon the nature of the lattice itself. As Rosenhain says, "If the lattice is comparatively soft and flexible the distortion is likely to be largely local. In a stiff lattice, however, local distortion will be resisted and there will be a correspondingly increased general distortion."

Jan 1, 1927

By Doris Stüben, Geoffrey P. Glasby, Akira Usui, Jörg-Detlef Eckhardt, Bruce W. Mountain, Zsolt Berner

"Abstract - Twenty-seven marine Mn and Fe deposits chosen for their diverse origins have been analyzed for five platinum-group elements (PGE). The PGE display their highest concentrations in hydrogenous Mn crusts and nodules, lesser concentrations in diagenetic nodules and two to three orders of magnitude lower concentrations in hydrothermal Mn and Fe crusts. This difference of behavior reflects the well-known fractionation of Mn and Fe from the other transition elements, rare earth elements (REE) and PGE in hydrothermal Mn and Fe crusts. Pt, Ru, Rh, and Ir show a close geochemical coherence in these deposits and are differentiated from Pd which shows a negative anomaly with respect to the other PGE in hydrogenous and diagenetic Mn deposits. Pd is less depleted than the other PGE and the Pd anomaly much less pronounced in the hydrothermal Mn and Fe crusts relative to the hydrogenous and diagenetic Mn deposits.Stability field diagrams show no evidence for the oxidation of Pt to the tetravalent state in seawater as suggested by some authors. Rather, Pt appears to be present in seawater as Pt(OH)2 0. Adsorption of Pt(OH)2 0 onto the surface of Mn and Fe oxyhydroxide minerals may explain the enrichment of Pt in marine Mn deposits. However, Pt metal is the thermodynamically stable solid phase of Pt under seawater conditions and reduction of Pt(OH)2 0 to Pt metal, particularly in the vicinity of the oxygen minimum zone, is possible, although the high Ce/La ratios of the Co-rich Mn crusts do not support this hypothesis. Pt, Ru, Rh, and Ir display their maximum concentrations in the Corich Mn crusts. This may reflect, among other things, the low growth rates of these deposits. The stability field diagram of Pd shows that Pd is undersaturated in seawater and occurs in seawater dominantly as PdCl4 2- and anionic mixed-hydroxide-chloride complexes. This would explain the anomalous position of Pd among the PGE with respect to its uptake into marine Mn deposits. A study of inter-element associations indicates that the incorporation of the PGE from meteoritic dust plays only a minor role in the uptake of these elements into marine Mn deposits. The PGE remain the most poorly studied group of elements in marine Mn deposits. The data presented here emphasize the need for the establishment of a more comprehensive database of the PGE in marine Mn deposits in order to understand more fully their uptake into marine Mn deposits and their pathways through the oceans."

Jan 1, 1999

By Andrew Dobson

The assessment and control of environmental noise from mines has become increasingly important in recent years, due to urbanization and population growth, increased regulation of environmental factors, and overall awareness and sensitivities to noise exposure. Minimizing adverse effects on communities and achieving compliance with local ordinances is now commonplace, and consideration of noise during the design and/or operation of a mine cannot be ignored. Ventilation equipment can represent the loudest and most bothersome equpiment at mines, however there are complexities when attempting to control the assocaited noise, due to the acoustical nature of mine vent fans. In fact, the utilization of traditional and/or industry standard methods can intensify the noise impact, or simply not work as intended. This paper provides recommendations on specific noise control methods that are suitable for mine ventilation equipment, based on recent assessment work and field experience.

Oct 1, 2024

By Marko Lampi, Ross Andrews, Jouni Pihlasalo, Robert Matusewicz

With widespread discussion on reducing carbon, sulphur and other emissions, use of sustainable energy sources and the pivotal circular economy theme, consideration needs to be given to pyrometallurgical operations broadly and more specifically, non-ferrous metallurgy. These themes present a number of challenges in terms of current operations and the view of processing the metals which are largely taken for granted in day to day living. This paper considers how these themes will impact pyrometallurgical flowsheets using the non-ferrous base metals as an example. It will examine the flowsheet chain to offer views on the boundaries of flowsheet optimization and the application of available tools to meet these future goals and challenges. INTRODUCTION The themes of reducing footprint through lowered CO2, S and other emissions, together with process sustainability (e.g. lowered energy) and links to the circular economy are well known to everyone in the metals industries. Whether it is reducing greenhouse gas emissions or analysing the importance of metals recycling in the circular economy, all these themes carry with them the fundamental premise of any change being considered; how can you best optimize a system to meet your aims? Of course, this depends on the available tools and the approach used for optimisation.

Jan 1, 2019

By P. G. West-Sells

At Barrick's Zaldivar Copper Mine in Chile, the addition of sulfuric acid to the ore going to heap leaching is a major expense. A process in which a portion of this acid is replaced by elemental sulfur added to the heap has been developed by Barrick and Westcoast Biotech that has the potential for significant cost savings. Initial shake flask tests with plant raffinate solution indicated that oxidation of elemental sulfur by a culture of sulfur-oxidizing bacteria, some indigenous to the Zaldivar heap, showed a significant lag period. This lag period could be reduced by dilution of the raffinate, but dilution would not be economical to implement at Zaldivar. Short (0.75 m) column tests indicated that after the initial lag period, sulfur biooxidation occurred steadily and the acid requirement for obtaining the same copper recovery as the control without sulfur was reduced by as much as 13 kg/t. These tests were followed by taller (5.1 m) column tests that confirmed the reduction in acid consumption, with no negative effect on copper extraction.

Jan 1, 2007

By M. Romana

"RMR geomechanics classification is being used all over the World as a useful tool for tunnel predesign and construction. Bieniawski (1989) provided guidelines for tunnel excavation and support, according RMR numerical values; guidelines which are now included in almost all tunnelling books, regulations, and Internet portals. But in the last 25 years tunnelling techniques have changed and some of the guidelines have become obsolete.. The conditions of tunnels for the 1989 guidelines application were: horseshoe shape; 10 m width; vertical stress < 25MPa; construction by drilling and blasting. Actually a substantial number of tunnels are mechanically excavated. The tunnel themselves are now bigger: a span of 14 m. is very common for transportation tunnels. The guidelines included the following concepts: excavation method, rock bolts (20 mm diameter, fully grouted), shotcrete, steel sets. There is an increasing gap between the 1989 guidelines and the practice: in many tunnels different to-the-case excavation and support requirements are established. Bieniawski himself has published a paper (Lowson & Bieniawski, 2013) with different guidelines based in Lowson’s practice, with no explanations and/or justification.In this paper a new set of RMR tunnelling guidelines is proposed taking account of the actual industry conditions, and increased safety regulations. The 5 classes’ limit RMR:values (80,60,40,20) are no more useful actually: Values of RMR (70, 50, 30) are used in practice to define quite different tunnelling techniques. Consequently a 10 subclasses system is proposed. Each subclass covers a span of 10 RMR points. As the number of mechanically excavated tunnels has increased a new correction factor is necessary, according the excavation method.The proposed 2014 RMR guidelines are for tunnels 10 to 14 meters wide, the world practice for new roads/railways tunnels. Many tunnels for water/ services are smaller with smaller support needs. Wider than 16 m caverns are out of the RMR system.It is not possible, nor desirable, to propose only a value for support in each subclass. The new guidelines propose an interval of values for certain types of support. More pessimistic values must be chosen for wider tunnels, tunnels with lower RMR values in each class and cases when a higher safety factor is asked for. More optimist ones are chosen for narrower tunnels, and higher RMR values. Some alternatives are almost complementary, others are contradictory. Sometimes several different techniques are proposed Guidelines are not automatic options. Good engineering judgment must be used when choosing between the different alternatives. Guidelines are not mandatory suggestions."

Jan 1, 2015

By L. H. Chen, Y. C. Chen, Leo Benyamin, W. C. Chen

"To investigate the evolution of fluid-driven fracture of rock-like material subjected to borehole fluid pressure and its consequential damage with regard to post-peak stabilization, micro-seismic activities have been monitored using nondestructive technique of acoustic emission (AE) corresponding to the macro-scale complete history of loading curve by setting the hollow cylindrical external circumferential strain to be a closed-loop feedback signal during servo-fluid-driven tests. Development of a novel fluidinduced loading system injected from internal borehole as well as monitoring system were equipped such that the initiation and propagation of micro-cracks enable to analyze experimentally. By programming/controlling either injection rate or fluid pressure, synthetic sandstones with low-permeability made by cement mortar were conducted in this study. It found that both the growth of macro-crack initialized intensively as reaching the breakdown pressure and the micro-seismic activities represented by AE locations show nice agreement. The experimental results in this paper provide better understandings of fluid-driven fracture mechanism.INTRODUCTIONFluid-driven fracture is a process of generating cracks by injecting viscous fluid into solid material. Conventionally, fluid-driven fracture tests have been performed by mining industry to measure the in situ stress (Haimson & Fairhurst, 1969) and fluid-driven fracture has been employed by the petroleum industry to recover oil and gas. Additionally, the mechanism of crack growth or the extension of existing cracks is important to the evolution of volcanic dikes over distances of a few kilometers (Lister & Kerr, 1991; Rubin, 1995), crack propagation in dams (Bolzon & Cocchetti, 2003) and the disposal of radioactive waste (Sun, 1969)."

Jan 1, 2015

By A. S. Eve

The detection of magnetic dykes by using magnetic variometers is the oldest application of. geophysics to mining, and is also one of the more simple and certain methods 0f locating such deposits. As a result of recent improvements in the instruments, it is now possible to find the dyke, deter-mine with magnetic variometers its strike and dip&apos;, with fair accuracy, and to estimate the approximate depth of overburden when there is no outcrop. The application of electrical methods may be used to distinguish mineral from diabase dykes. The authors have had an opportunity of making surveys with the modern Askania types of vertical and horizontal variometers over magnetic dykes in the Sudbury region. The interpretation of the results has been confirmed by diamond drilling in some cases, and by experiments over models. The variometers used were the standard form of Askania instruments (1). The sensitivity of the horizontal type was 17.2 gammas per division, and that of the vertical variometer double this quantity. To make a preliminary survey of the district, parallel lines were laid off two hundred feet apart running north and south, and readings were taken with the vertical variometer every 100 feet along these lines. This can be done very rapidly, and when an indication of a magnetic deposit is found, the readings may be taken every hundred feet, or less if the size of the deposit warrants smaller intervals. If the deposit is a vein or dyke, the readings along the adjacent lines immediately indicate the strike of the body. Thus the presence and strike of a magnetic dyke, whether of mineral value like the pyrrhotite and nickel deposits of the Sudbury district, or simply a worth-less diabase dyke, is simply and rapidly found.

Jan 1, 1932

By M. Côté, H. Pépin, Y. Richer, C. Gingras

Rolls-Royce Canada has been nominated as a Rolls-Royce Center of Excellence for repair of fan blades in 2003. One of the challenges of the Rolls-Royce Canada Component Repair Center of Excellence team is to reduce cost and time of inspection while ensuring trace ability and quality of the inspection performed on the fan blades. In the context of the dimensional control process optimization, and following the positive conclusions of initial trials carried out in 2003, the technical authorities at RRC have selected the SPG data 3D(TM) technology as a development base for dimensional control programs. The main goal of this development initiative is to develop and support an inspection system to perform the dimensional control and inspection of different components at the Montreal Fan Blade Repair Center of Excellence. The final objective of the program is to build a server platform capable to support different inspection sites within the Montreal facility for the future. This paper presents the certification process of the technology according to the VDI-VDE 2633 certification standards and some results of the fan blade inspection program of the BR 710, BR 715 and TAY according to the JES 195 engineering standards specification.

Jan 1, 2006

By E. Ghali, J. F. Dorion

This paper presents the results of on-going investigations on the influence of corrosion on the performance of support systems in selected underground gold mines. Rock support is exposed to various conditions that can be aggressive. Samples of corroded support were analysed using SEM and photomicrography to determine the main corrosion forms. Tests are on-going in controlled corrosion chambers to qualify and quantify the impact of rock and minerals particles on steel corrosion. As more data become available these relationships can lead to useful information on the choice of support systems and reliable estimates of their longevity.

Jan 1, 2011

By R. Simon, A. Khosravi

"Tensile strength of rock samples is measured by direct and indirect tensile tests in accordance with standard guidelines. Due to the difficulties in performing direct tensile test, the indirect tensile (Brazilian) test is conventionally carried out to obtain the ultimate tensile strength. A limited number of studies have been conducted to investigate the role of sample size (length to diameter ratio = L/D) in the stress distribution of the Brazilian test using numerical and analytical methods. These investigations showed that the tensile stress distribution along the loading diameter is not uniform. They also indicated that the difference between the tensile stress at the middle part and at the sides of the sample with higher L/D ratio is greater than that in the other samples.The objective of this study is to show the effect of tensile stress distribution on the fracture surface created by the Brazilian test from a morphological point of view on the samples with different L/D ratio. Hence, a series of fracture surfaces created using the Brazilian tests on the rock samples with L/D of 0.5, 0.75, 1, 1.25 and 1.5 were investigated.In this study, all fracture surfaces were scanned by a 3D laser profilommeter. A number of roughness profiles parallel and perpendicular to loading axis have been selected from the samples with different L/D ratio and spacing of 1 mm. The results show that the roughness of the profiles perpendicular to the loading axis increases with an increase of L/D ratio, while the roughness of the profiles parallel to the loading axis decreases. Furthermore, some roughness profiles parallel to the loading axis were chosen and divided into three segments. The results revealed that the segment in adjacent to the upper loading platen possesses higher roughness than the other segments."

Jan 1, 2015

By L. Yuan, J. H. Rowland, R. A. Thomas, D. Bahrami, G. P. Cole

"The past several decades have seen a steady increase in the use of atmospheric monitoring systems (AMS) in underground mines as sensor technology has advanced and costs for this technology have decreased. The AMS is a reliable tool for early mine fire warning by detecting gaseous products of combustion in underground mines. During a mine fire emergency, mine decision makers rely heavily on the prompt and accurate knowledge of the ventilation and fire situation in the mine, such as fire location, fire size, and the spread of smoke to make effective and efficient decisions on firefighting strategies and miner evacuation. Meanwhile, a prediction of the potential for fire development at a later time, such as whether the currently designated mine escapeways will be contaminated by smoke and toxic gases with the progress of the fire, is critical for effective decision-making to save lives that are in danger. The AMS monitoring data, including carbon monoxide (CO) concentration, airflow rate, smoke, etc., can provide information as to whether the smoke has reached the locations where AMS sensors are installed and if a mine-wide smoke spread has occurred. The National Institute for Occupational Safety and Health (NIOSH) has undertaken a task to integrate real-time AMS monitoring data with the mine fire simulation program, MFIRE, to simulate and predict the spread of smoke and toxic gas in a ventilation network based on the real-time AMS data. This paper reports the developed real-time method for characterizing the size and location of an underground mine fire and for predicting the spread of contaminants throughout the mine ventilation network using sensor data from the AMS.INTRODUCTIONNIOSH conducts research to develop workplace solutions to improve detection of and reduce the risk of hazardous conditions in underground mines. The advancement of senor technology and the increasing demand for real-time mine parameters monitoring have led to extended applications of atmospheric monitoring systems (AMS) in underground mines worldwide. In the United States, AMS is primarily used for early mine fire warning by detecting carbon monoxide (CO) in fire hazard areas, such as belt entries. Mine fires can grow rapidly, and time is the critical element. Prompt detection, timely and accurate warnings to those miners potentially affected, and a proficient response by underground miners can have a tremendous impact on the social and economic consequence of a small underground mine fire (Conti et al., 2005). The early detection of a mine fire could gain time for the first responders to put out the fire before it develops into a disaster. An AMS system with CO sensors has especially played an important role in the early detection of mine fires. The continuous monitoring of an underground mine atmosphere with an AMS could generate a large amount of data in a mine fire event. However, the current application of AMS is mainly limited to sending out an alarm when monitored CO concentration exceeds a certain level. An opportunity arises as to whether these data can be further used in fire emergency response. In order to make effective decisions on firefighting strategies, mine workers’ seeking refuges, evacuation and escape, and the timing on when to send rescuers, decision makers need accurate and timely knowledge of the ventilation and fire situation in the mine. Information about the fire intensity, where in the mine the smoke and toxic gases have spread, and whether designated mine escapeways have been compromised by smoke and toxic gases from the fire would greatly increase the effectiveness of these decisions. However, the monitored AMS data only provides atmospheric conditions in the vicinity of sensor locations. What is concluded from the monitored AMS data highly depends on the decision makers’ capability and experience. Predictive insight into fire growth and smoke transport would greatly help decision makers during a fire emergency."

Jan 1, 2019