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By David H. Searle

This paper will discuss the common trends existing in various Canadian jurisdictions for the closure and reclamation of mines. Included will be a discussion of the requirement to post security as well as its form and how security is calculated and refunded. Reclamation can no longer be left to the end of mine life. Progressive reclamation must occur throughout mine life and must be part of the mine plan from the beginning.

May 1, 2006

By Lyman Moore

This Bureau of Mines report describes 2nd evaluates iron ore resources in California and Nevada and analyzes the California and Japanese iron ore markets in which these resources will be used. The competitive position of California-Nevada ores, in these markets, was estimated by comparing regional iron ore prices, production costs, and transportation costs with those of foreign suppliers. Resources were determined to be sufficient to produce the equivalent of 585 million tons of 64-percent iron pellets at a price of less than $15 per ton delivered at California ports. Much higher tonnage could be produced at higher prices. Iron ore requirement of the California iron and steel industry will increase to an estimated 15.9 million tons by the year 2000. A study of the iron ore production potential of California-Nevada deposits and of out-of- State sources indicated that this ore requirement can be supplied most economically by California-Nevada ores. Iron ore import requirements of the Japanese iron and steel industry will increase to an estimated 150.0 million tons by the year 2000. A study of price trends in this market indicated that very little California-Nevada iron ore will be sold in Japan after 1973 when existing sales contracts expire. Iron ore-exports might be economically possible if ore could be transported from California to Japan at ballast rates as backhaul on existing petroleum shipping.

Jan 1, 1971

By R. H. Grau, S. B. Robertson, R. B. Krog

The National Institute for Occupational Safety and Health (NIOSH) has conducted research to improve the ventilation of large-opening mines. Large-opening mine ventilation is unique for the following reasons: (1) it is challenging to keep airflow velocities high enough to effectively remove or dilute airborne contaminants, (2) large air volumes can be moved through the mines with little static pressure drop, and (3) stoppings to direct ventilation airflows are costly to construct and maintain. The research results suggest that by incorporating ventilation planning into the mine planning process, using propeller fans, developing new stopping materials and construction methods, and using long pillars to eliminate crosscuts where possible, the ventilation of large-opening mines can be significantly improved. The ventilation improvements created by incorporating these various techniques into the ventilation plan will help reduce the exposure of mine workers to airborne contaminants in underground large-opening mines.

The extraction and processing of minerals from surface mines and quarries can produce significant fugitive emissions as a result of site activities such as blasting, unpaved road haulage, loading, primary crushing and stockpiling. Uncontrolled fugitive dust emissions can present serious environmental, health, safety and operational issues impacting both site personnel and the wider community. Simulation technology is finding increasing use for the purposes of advanced warning of potential problem emissions in addition to providing a basis for future planning applications where demonstrable compliance with regulatory requirements are necessary. The initial re-entrainment and subsequent dispersion of fugitive dust presents a process complicated by the combination of the in pit topography, the surrounding natural topography and the dynamic nature of emissions from these sites. These factors impact upon the accuracy and reliability of the conventional Gaussian plume based computational prediction methods employed for regulatory compliance and IPPC applications. This paper proposes that optimal modelling of open pit emissions may be more accurately achieved by the use of a multi-scale predictive modelling approach utilizing computational fluid dynamics (CFD) methods for high resolution near source dispersion and conventional Gaussian based methods for far field dispersion modeling. This paper presents a numerical based flow and dispersion analysis of a typical UK based open pit utilizing CFD in conjunction with a conventional Gaussian plume based methods. Typical operating emissions and meteorological conditions are obtained from long term data records collected at a large operating quarry extraction operation in the UK. Emissions are modelled using a Lagrangian framework within conventional atmospheric boundary layer (ABL) profiles expressed as functions of turbulence and velocity parameters under assumed neutral conditions. Results are presented in terms of the impact of site topography on in pit retention as compared to the Gaussian based method.

Jan 1, 2009

By V. “Ram” Ramachandran

"In view of the increasing number of environmental regulations that have been promulgated all over the world in the last thirty years, non-ferrous smelters and refineries have had to learn and adapt to treating process bleed waste streams containing heavy metals. The result of such treatment invariably yields a gypsum-saturated solution containing salts such as alkali metal sulfates, chlorides and fluorides. Presence of anions such as sulfates, chlorides and fluorides in the discharge streams – presently not a major problem- are coming under increasing scrutiny and will have to be addressed in the near future. It is envisaged that discharge limits for sulfate ions will be in place in the near future. Treatment of brackish water to produce drinking water also results in brine streams containing alkali salts that have to be addressed for proper disposal. This paper reviews treatment options for such streams containing high levels of total dissolved solids with emphasis on sulfate removal. Areas covered would be: a) chemical treatment for removal of various constituents that make up the total dissolved solids b) processes for sulfate removal processes –thermal and non-thermal-to recover and reuse of treated water and c) brine use and treatment options.INTRODUCTIONThe rising cost of water and meeting the ever-changing stringent environmental discharge regulations make water recycling and reuse essential. The metallurgical industry has used water as a medium for dissolving and/or rejecting metals and chemicals in addition to removing thermal energy. Any excess process effluent is collected and sent to end-of-pipeline treatment and ultimately discharged to surface water for disposal under a permit. The conventional- and probably the cheapest way -of treating metal-bearing process effluent streams is lime neutralization followed by sulfide polishing for elimination of heavy metals to produce a stream that meets NPDES discharge limits. This results in a stream containing dissolved solids.These dissolved solids normally comprises of inorganic salts. The possible constituents are cations calcium, magnesium, sodium and potassium. The anions are sulfate, chloride, fluoride, nitrate, carbonate and bicarbonate. In addition to these constituents, the treated effluent streams contain very small amounts of heavy metals, oxyanions such as arsenites, arsenates, selenites and selenates. Process streams from gold operations contain residual cyanide. Small amounts of ammonium ions are also present in these streams based on the pH of the solution."

Jan 1, 2012

By P Stone, J. M. Cook, P. R. Simpson, C Mcdermott

Paper presented at the conference Economic geology in Europe and beyond II, models for mineral deposits in sedimentary basins, held in Keyworth, UK, 13-14 April 1994. The SW part of the Southern Uplands is a back-arc section of an accretionary thrust system, divided into structural blocks by major NE-SW shear zones and NW-SE faults forming the margins of Permian half-grabens. The highest arsenic levels in stream sediments (over 65 ppm) are associated with those blocks carrying brittle-ductile transition fabrics. Three factors combine to recomend the area as having potential for gold mineralisation: As-rich greywackes as country rock, felsic intrusions and a major shear zone. Selected stream sediments were analysed for gold using lead fire assay with ultra-pure flux and ICP-MS finish. Several localities showed over 15 ppb Au, the three most significant being within the hanging wall of the Orlock Bridge Fault and each having distinct characteristics

Aug 1, 1995

By M. K. Abd El-Rahman

A complete chemical analysis of the waste showed that it contains 15.64% P2O5; X-ray diffraction analysis revealed that it is composed mainly of francolite, calcite, pyrite, quartz and dolomite. The phosphate values were recovered and the settling rate of the wastes enhanced by the use of hydrocyclone and flocculation techniques. The hydrocyclone produced an underflow enriched in phosphate and an overflow enriched in clays. The former represented 39.8% by weight of the phosphatic clay waste and assayed 26% P2O5 at a recovery of 66.36%. The results of flocculation of the phosphatic clay waste showed that both the degree and rate of settling were increased and that the process water could be recycled. The settling rate was 37 times greater when anionic polyacrylamide A130 was used

Jun 21, 1905

By Y. L. Su, S. Vongpaisal, H. A. Smith

"It is extremely difficult for a mine's central control room operator to control peakpower demands and to maintain normal materials handling operations at the same time. An investigation of the Falconbridge Strathcona Mine 's central control room has revealed that there are more than eight thousand possible combinations of ""situations"" that can arise. For such a circumstance, an expert system can become a very valuable tool to assist the operator in taking the most appropriate and timely action.A forward chaining expert system module has been developed for this application. The module is based on Level 5 ObjectTM software. It is graphics oriented and user-friendly. Training requirement is minimal.ForewordThis paper has arisen out of work carried out by YLS Associates and Falconbridge Limited as part of a contract between Falconbridge and the Department of Energy, Mines and Resources, Government of Canada, on the application of expert systems in mining operations.IntroductionThe electrical bill charged to large consumers by Ontario Hydro is based upon two elements: demand and energy consumption. The demand is the peak kilowatt level that the consumer has required during a monthly period. It is not uncommon for the demand portion to be as much as one third of the monthly bill. Energy consumption is the total kilowatt-hour s (kWh) consumed during the period.Ways to reduce the energy consumption part of the electrical bill involve utilizing energy-efficient equipment and operating machines in off-peak hours when a lower energy rate is charged. Maintaining the peak power below a critical level may require that simultaneous usage of major pieces of equipment be avoided. A 3000 kW skip run at an inopportune time could cost a company an extra $30,000 in that month's power cost.Potential disadvantages associated with peak power control are lost production due to work stoppage and increased operating costs due to the need to employ extra personnel. Most companies find these matters relatively easy to deal with and with incentives provided by Ontario Hydro, actively pursue this facet of energy savings (Harju , 1991)."

Jan 1, 1993

By Michael Wieland

For shooting rock properly, some relatively fixed quantity of rock work is required from the total charge mass, while keeping the overall toxic fumes to a minimum. The overall fumes weighted for the toxicity of different species and taken per unit charge mass, ??, are represented by a relative fume toxicity (RFT) formula. The worst two contributions are often carbon monoxide {CO} and total nitrogen oxides {NOX}, so the traditional Russian formula RFT-R formula suffices, though a generalized form RFT-G with more terms is worth checking. Using the work-principle model from thermodynamics, the rock work per unit charge mass, ??, is found from the reduction in internal energy for the reaction zone. This resolution technique for rock-work invokes the usual assumption that the quick irreversible process occurs without notable heat transfer to the rock (adiabatic); rock-work is not resolved, when this restriction is untenable. The ratio of ?? to ?? yields the weighted toxic fumes divided by the rock work or the readjusted fume toxicity ??, where ?? = ??/??. For convenience, graphical trends of ??, ?? and ?? were normalized using reference results for a stoichiometric (ANFO) mixture of ammonium nitrate (AN) and fuel oil (FO) shot under nominal rock confinement, noted later.

Jan 1, 2006

Rockbursts continue to be a scourge in the mining industry, being responsible for accidents and damage to mining excavations. Although the problem has been present for more than a century, and although much research has been carried out, a solution is still elusive. Determination of, firstly, the demand on the support system imposed in the rockburst and, secondly, the capacity of the support system, cannot be carried out with any confidence, and therefore rockburst support cannot be designed using a conventional design approach. In contrast with the conventional approach, observations of rockburst damage in a mine have revealed a possible alternative approach to rockburst support ? sacrificial support. It was observed, in rockburst events, that a support system consisting of concrete panels restrained by grouted cables was destroyed, and the concrete panels were ejected. However, the rock behind the panels remained apparently undamaged and in place. This behaviour reignited the concept of sacrificial support, conceived more than 20 years ago, and which is described in this paper. The remedial solution implemented on the mine, involving cables wrapped over the panels and retained by grouting into boreholes, has been subjected to rockburst loading and has confirmed the validity of the sacrificial support concept. The concept of sacrificial support may be controversial, but is deliberately presented here with the aim of generating discussions and contributions, and with the ultimate aim of improving safety and reducing rockburst damage in mines. Keywords rockburst, seismicity, seismic waves, rock support, support design.

Jul 1, 2013

By S C. Dominy

Various styles of gold mineralisation pose problems during sampling because of their complex gold grade distribution and presence of coarse gold. Effective sampling and sample preparation forms the basis of resource estimates. The design of a sampling and assaying protocol must be based on a thorough understanding of the mineralisation in question, which should include consideration of gold particle size and mass distribution. The proportion of coarse gold within samples has a profound effect on the requirements for sample preparation and assaying. Choice of preparation procedure and assay type is of critical importance if sampling errors are to be minimised. Traditional fire assays, using small charge sizes, often understate assays gained from large charge sizes and techniques such as screen fire assay and LeachWELL. Proper application of the Theory of Sampling reduces errors during collection, preparation and assaying. A quality control/quality assurance program must be implemented and critically assessed. A case study from the Ballarat mine is presented, which is characterised by substantial quantities of coarse-gold hosted in quartz veins. Diamond core drilling is the key input into resource delineation. A number of different sampling and assay options have been trialled over the recent project history. The current sampling protocol utilises whole drill core, using LeachWELL assays after logging and photography.CITATION:Dominy, S C, 2017. Sampling coarse gold-bearing mineralisation – developing effective protocols and a case study from the Ballarat mine, Australia, in Proceedings Eighth World Conference on Sampling and Blending , pp 71–84 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By W. Mbhalati

"Conzal Mine was not meeting production targets in 2013, and it was established that this was caused by the inability of the load haul dump machines (LHDs) to tram the required tonnages. An investigation of the LHD productivity was therefore conducted to identify the inhibiting factors. This was accomplished by carrying out a literature review on LHD operations to gain in-depth knowledge and conducting observations in the working environment. The relevant information and data on the LHD type used at Conzal was also acquired.The major inhibitor was found to be excessively long tramming distances in all the sections of the mine. The one-way tramming distances were all significantly greater than the 90 m set in the mine’s code of practice (COP), with the Main Shafts section having the longest average one-way tramming distance of 260 m. The other inhibitor was LHD utilization, which in 2013 was only 47% against a target of 70%. Simulation of the LHD operation, taking these two factors into account, showed that production could be increased by more than 100%. As a result, it was recommended that conveyor belts should be extended regularly in order to keep tramming distances within the recommended one-way distance of 90 m. In addition, utilization can be improved by minimizing employee absenteeism as well as by modifying the travelling routes such that LHDs do not encounter unnecessary delays.Paper written on project work carried out in partial fulfilment of BSc. (Mining Engineering)"

Jan 1, 2015

By W. Valderrama, D. G. Almond

Operation of large SAG mills requires a change in the conceptual approach to grinding processes. The traditional energy consumption criteria are now enhanced with new criteria derived from the mechanical dynamics of the mill load. This new approach demands instrumentation capable of providing accurate information about the load movement and the ratio of balls and ore inside the mill. This paper discusses two new performance enhancing tools available to meet these needs.

Jan 1, 2004

By S. H. Ash

THE INUNDATION of anthracite reserves in the Eastern Middle field of Pennsylvania affects the life of the anthracite industry in this field; it also influences the economic status of people, communities, and industries that depend wholly or in part upon anthracite for their livelihood. The trends of production and of employment in the anthracite-mining industry in this field are downward, and they probably will continue in this direction. The reserves have been depleted to the extent that the end of the active life of the industry as a. major economic factor is approaching. By removing the water in those pools where it can be done economically, the future of this industry may be extended somewhat.

Jan 1, 1950

By M. Z. Emad, A. Hassan, M. A. Raza, M. U. Khan, S. A. Saki

Digital modelling of a surface is crucial for Earth science and mining applications for many reasons. These days, high-tech digital representations are used to produce a high-fidelity topographic surface in the form of a digital terrain model (DTM). DTMs are created from 2D data-points collected by a variety of techniques such as traditional ground surveying, image processing, LiDAR, radar, and global positioning systems. At the points for which data is not available, the heights need to be interpolated or extrapolated from the points with measured elevations. There are several interpolation/extrapolation techniques available, which may be categorized based on criteria such as area size, accuracy or exactness of the surface, smoothness, continuity, and preciseness. In this paper we examine these DTM production methods and highlight their distinctive characteristics. Real data from a mine site is used, as a case study, to create DTMs using various interpolation techniques in Surfer® software. The significant variation in the resulting DTMs demonstrates that developing a DTM is not straightforward and it is important to choose the method carefully because the outcomes depend on the interpolation techniques used. In mining instances, where volume estimations are based on the produced DTM, this can have a significant impact. For our data-set, the natural neighbour interpolation method made the best predictions (R2 = 0.969, β = 0.98, P < 0.0001).

Feb 6, 2023

The history of zinc production in Australia is outlined including attempts to make zinc electrolytically at Cockle Creek, N.S.W. in the last century, the use of horizontal retorts at Cockle Creek and Port Pirie, South Australia, production by electrolysis at Risdon, Tasmania and at Port Pirie using zinc oxide fumed from lead blast furnace slag and production by the Imperial Smelting process at Cockle Creek. Developments in the electrolytic process are described including those in roasting, acid manufacture, leaching, purification, electrolysis, melting and casting. The Imperial Smelting process technology is also outlined. In both processes global technology is reviewed, including important Australian contributions.

Jan 1, 1986

By S Kundu, J Zanganeh, D Eschebach, B Moghtaderi

The concentrations of methane and coal dust vary from one location to another in underground coalmines. In the presence of an ignition source, such as static electricity, these mixtures can initiate explosions and consequently cause massive destruction. Research data can help in understanding the level of hazards and associated risk these flammable mixtures can produce. For instance, the level of peak explosion pressure and flame speed can be well understood from experimental and numerical research data. With this aim, methane–air mixtures and methane-coal dust-air mixtures were employed in a ducted spherical vessel. According to literature, the maximum value of peak explosion pressure can be obtained in vessels of spherical geometry when compared to vessels of other geometries. Thus the values of explosion parameters generated from spherical vessels can be incorporated in understanding the highest level of hazard that can occur in a real world scenario.In this study, the duct integrated with the vessel resembles any channel or pathway connected to a methane and/or coal dust rich area in the mine. Experimental investigations emphasise that the severity of explosion in the explosion zone transmits to the channel or pathway. The length of the channel or pathway also plays an important role on the values of explosion parameters. The greater the length of the channel or pathway, the higher the explosion pressure is and therefore the higher the destruction. Ignition energy and concentrations of methane and coal dust were varied in collecting experimental data. The data of explosion parameters thus obtained can be employed in addressing hazard mitigation strategies in coalmines.CITATION:Kundu, S, Zanganeh, J, Eschebach, D and Moghtaderi, B, 2017. Incorporating research data in addressing methane and coal dust fire, and explosion hazards in coalmines, in Proceedings Australian Mine Vent Conference 2017, pp 175–180 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By R. V. Ramani

"A computer simulation model of a dragline has beer developed for the study of alternative dragline deployment schemes for varying geological and mining conditions. In this paper, the mathematical aspects of the model, the input data and output results are discussed. An application of the model to a coal mine in eastern Kentucky is presented.IntroductionDraglines are very productive machines. To extend their operating ranges, they are operated in several modes such as advance benching, key cut, extended benching and pullback. Unfortunately, these variations result in low machine productivities. Appropriate methods to operate these machines must be developed on the basis of detailed analyses of dragline performance under varying geological and mining conditions. There are several standard engineering procedures for the selection of dragline, and design of a dragline pit (Ramani, Iroegbu and Manula, 1976). However, the complex interrelationship which exists among equipment, methods and natural conditions can be quantified only through orderly and systematic experiments.Computer simulation is well suited to studying these types of equipment selection and method layout problems. Several alternatives can be analyzed in a relatively short time by the modification of input variables. Also, the application of computer simulation models can significantly reduce the manpower and cost required for such analysis."

Jan 1, 1985

By T. Lux, M. Hanel, Degel, A. Filzwieser, R., H. Joubert

It is the increasing demand for an economic and cost saving operation mode that requires effective cooling in order to achieve low refractory wear and good furnace lifetime, which is making cooling technology an important aspect of furnace operation. In addition, the requirements for safety are getting more and more into focus. However, the use of water—today’s standard cooling medium—has major drawbacks as it can cause problems both during furnace start up and operation, namely hydration problems, corrosion, and explosion. Not to forget the severe risks for the operators as well as economical damage in case of a malfunctioning water cooling system. With this new and patented cooling technology ILTEC and the ionic liquid IL-B2001 as the cooling medium, it is possible to realise a water-free cooling solution and therefore the door is wide open to rethink existing and conventional cooling solutions. Furthermore, there is also the chance to recover heat from the process in a more efficient way. However, since the technology is novel and unique there are a lot of concerns and doubts regarding safety for plant operators and employees. The paper is intended to cover both: highlighting the enormous potential of the technology but also to eliminate concerns mainly caused by rumour and unawareness. INTRODUCTION All of us are aware of the risks when water is used as a coolant and placed in the vicinity of the liquid metal phase. Unsuitable design solutions or wrong operation modes of the furnaces or failures of refractories can cause a direct contact of water with liquid metal. The consequences can lead to equipment failures, vessel destruction but even worse to injuries and even fatalities. Over the past decades, countless incidences were reported. Fatal accidents caused by water coming into contact with liquid metal happen every year (Oterdoom, 2014; Filzwieser, Konetschnik, Filzwieser, Wallnerm & Preiss, 2014). With the novel ionic liquid cooling technology virtually all negative effects of a water cooled system regarding safety are eliminated and even additional benefits can be provided (Voermann, Ham, Merry, Veenstra, & Hutchinson, 1999;Verscheure, Kyllo, Filzwieser, Blanpain & Wollants 2006; Wallner, Filzwieser & Kleicker 2006). The fact that no explosion occurs when IL-B2001 gets in contact with molten metal results in a revolutionary solution for the metallurgical industry in terms of safety—new safety standards can be achieved.

Jan 1, 2019

By Alvin Kaufman

To aid industry and Government in planning water developments the Bureau of Mines in 1963 canvassed mineral producers to determine water use in 1962. Water use by the mineral industry comprises only 2 percent of the water withdrawn by industry as a whole. The major water-using mineral industries are natural gas processing, phosphate rock, sand and gravel, and iron ore. Analysis indicated the following conclusions: 1. Total water use and new water intake is dependent on the quantity of material processed and the process water requirements of the particular industry or commodity. 2. Recirculation is dependent on the processing requirements of a particular commodity, the manner in which the water is used, cooling and condensing requirements in certain large industries, the quality of new water intake, and the need to treat new and discharged water. 3. Consumed water is dependent on the quantity of water recirculated, the temperature and humidity in the area, and the proportion of water used for cooling and condensing. 4. A threefold increase in water use by the mineral industry by 1985 is forecast.

Jan 1, 1966