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By George A. Lawrence, J. C. McHardy

"Field operating experience with an improved flotation mechanism for handling various flotation applications is covered in this paper. Some aspects of designing flotation machines are also presented. Operating data from extensive testing of commercial size equipment under actual plant operating conditions in the following applications is detailed:1. Copper Flotation2. Fine Coal Flotation3. Base Metal Sulfide FlotationDesign features, design improvements, modifications tested, and overall performance data are reviewed. Some mecl1anical performance data as well as metallurgical performance results are presented. Some comparisons with conventional flotation equipment are reported in this paper.Flotation sizing theories are reviewed and an actual equipment selection ex2.mple is presented. Scale-up criteria used for developing large cells are briefly covered.The paper concludes with a brief review of anticipated future flotation equipment design needs. IntroductionThe mining/milling industry is faced with increasing pressure to cut costs while maintaining product quality and indeed, in some instances, expanding production. For copper, nickel, iron, molybdenum, lead and zinc sulphides, coal, phosphate and some other minerals;, flotation remains the primary method of concentration and recovery of the valuable mineral away from the gangue. Cost reduction in flotation can be broadly focused on two areas:1. Flotation Chemicals2. Flotation Equipment"

Jan 1, 1985

By John Popovich

The MICON RokLok binder system including component and consolidation processes and safety and its first aide are described. The implementation procedures and selection of injection parameters are discussed. Finally a case example of recovering a 30-ft. long roof fall in mainline haulage entry is used to illustrate the economic potential of preventive measures by RokLok injection.

Jan 1, 2001

By R. K. Jade

Although several studies in combining and bifurcating flows in two-way junctions and splits are reported, deviations persist in the estimated shock loss coefficients (SLCs). Due to their complex nature, more work has to be done to be able to correctly predict flow losses at these locations. In two-way splits, the flow at bifurcation is known to be characterized mainly by two recirculating zones in the downstream branches, whereas, in a junction one recirculating zone is observed immediately downstream of the main branch. The relative flow rate in the branches (quantity ratios) is treated as the only parameter defining the losses at these locations. However, the effect of wall roughness, if any, on SLCs becomes important for mine ventilation. This paper presents the critical determinants of shock losses at splits and junctions at varying quantity ratios. The flow at 90º split and junction was examined both experimentally and numerically for Reynolds number in the range of 1.0×104 to 1.6×105. With a well designed laboratory setup, using precision instruments, velocity and pressure measurements were carried out, by using two scales of wall roughness. 3D numerical simulations for these experiments were conducted by using ANSYS CFX modeling tool. CFD simulations yielded results that are reasonably close to experiments, providing high degree of satisfaction in numerically predicting losses across the splits and junctions. However, comparisons of these numerical simulation results with existing literature standards showed significant under-estimation of shock losses by the standard literature by as much as 50%. A clear rise in the magnitude of shock losses was noted in both the approaches, with increased wall roughness. Based on the current studies, predictor equations incorporating quantity ratios are developed for accurate estimation of shock losses. Further investigations on roughness are needed, before one is able to incorporate wall roughness into the prediction of SLC.

Jan 1, 2009

By Randall S. Marks

Bonneville Dam, completed in 1938, included the smallest and busiest lock on the Columbia and Snake River Navigation System. To expedite barge traffic through this restriction, a new larger lock was designed and contracted by the U.S. Army Corp of Engineers.

Jan 1, 1997

"The Dumont deposit is a large (1066 Mt probable reserve) low grade (0.27% nickel), nickel sulphide project located in the Abitibi region 25km west of Amos, Quebec. Royal Nickel Corporation acquired the project in 2007 and has since taken the deposit through pre-feasibility. And updated, revised pre-feasibility was released in July 2012.The disseminated nickel sulphide and alloy mineralization is hosted within the serpentinized dunite subzone of the Dumont Sill; a differentiated, pervasively serpentinized, ultramafic sill of komatitic affinity. Pentlandite, heazlewoodite and awaruite are the dominant nickel-bearing, metallic phases and can be recovered by conventional methods (flotation, mag separation). Non-recoverable nickel is also present within the silicate matrix of the serpentinized dunite and is locked in serpentine (Fe and Mg-rich variants) and minor olivine.A detailed mineralogical program including 1097 QEMSCAN® samples and 4300 electron microprobe points were undertaken to increase the understanding of the nickel deportment in the various recoverable and non-recoverable phases in a spatial context across the deposit. Eighty-three (83) metallurgical tests performed under a standard procedure have linked the mineralogy to metallurgical performance. This has allowed the creation and modelling of geometallurgical domains on a block by block basis to understand the recovery variation and metallurgical performance throughout the deposit. Understanding the spatial variability of Ni deportment in recoverable and non-recoverable phases through mineralogy is the key to understanding metallurgical performance thus, unlocking the value of the Dumont deposit and other large tonnage low grade ultramafic nickel deposits."

Jan 1, 2013

By Paul C. Schmall, Arthur B. Corwin, Derek Maishman

Ground freezing occupies a unique and important niche in underground construction, fulfilling a geotechnical need that is difficult, or sometimes impossible, to fulfill through other groundwater control and excavation support methods. Where complete groundwater cut-off and in-built ground support are required, and deep excavation is planned or the work occurs in difficult or disturbed ground, ground freezing offers the assurance critical to safe and timely construction. Compared with other groundwater cut-off or excavation support methods, a frozen wall is easily connected to underlying bedrock and will also adhere to adjoining subsurface installations or obstructions, if necessary, to provide a composite cutoff structure. Ground freezing is effective in all soil and ground conditions and has been used for emergency situations in disturbed, displaced or loose ground, where detailed soil characterization could not practically be performed.

Jan 1, 2005

By John Babcock, Bryan C. Smith

In a partnership between Luck Stone Corporation and Loudoun Water, a 42” (1.067m) steel pipeline was constructed along the perimeter of an extensive permitted reserve of diabase rock Luck Stone was about to begin mining. Loudoun Water provides drinking water and wastewater services to over 75,000 households in Loudoun County, Virginia. In discussions to establish the 30-foot (9.1 meter) easement for Loudoun Water within the permitted reserve of diabase rock, Luck Stone and Loudoun Water agreed on the following basic conditions: • Luck Stone could execute production blasting as close to the easement as physical conditions of overburden depth permits. We estimated the minimum distance to be about 75-feet (22.86 meters) from the centerline of the pipe. • Loudoun Water would install strain gauges on the pipe every 500-feet (152.4 m) along the entire length of the future reserve area. This resulted in the installation of 18 strain gauges. • Luck Stone would contract a third-party vibration monitoring company, agreed to by Loudoun Water, to monitor the strain gauges and provide seismograph reading at appropriate locations along the pipe as mining progresses. All information would be provided to Loudoun Water. • Luck Stone’s blasting will be conducted in a manner that ensures the recommended strains are not exceeded.

Jan 1, 2019

By Steven B. Van Kouteren

Value added is a loosely used qualifier in the industrial minerals industry. What exactly does it mean? What does it take to make a value-added product? More importantly, how does a company maintain the value added to its products? Most people agree that value-added means the value of a mineral minus the cost to produce it. This is misleading, though, because producing value-added products does not necessarily guarantee the profitability of the products. In some cases, firms that make value-added products are not very profitable. It is important not only to understand how to make a value-added product but also how competitive forces in the market can erode the value added. Therefore, when looking at value-added opportunities, producers must understand how to obtain the value added and how to maintain that value. Four major factors limit a company's ability to add value to its products. This paper examines these factors. It uses the ground calcium carbonate and mica industries as examples.

Jan 1, 1990

Good morning and thanks for the chance to talk to you. It's really pleasing to see so many industry representatives here I want to spend a few minutes talking about issues relating to your industry. At the end of today I would like to leave you with three strong messages from government. The first is that this government supports environmentally responsible mining and the endeavours of the mining industry. The second is that explorers and developers are wanted and welcomed in New Zealand. And the last is that it is up to the industry to keep the public properly informed about how your industry and to constantly work on improving your public image. The mining industry is a high-tech industry which fits snugly with our concept of a growing knowledge-based economy. It has particular value for regional development, the gold mining industry alone provides more than 4,000 jobs û mostly outside of the main cities. The industrial minerals industry is twice as large as that. As well as those people directly employed by the industry there are greater downstream effects for the community. One example from the broader extraction industry of this is of the local pie shop down the road from one of Taranaki's petroleum industry locations. The shop sells over $4,000 worth of pies a week to workers in the industry. That's just one example of the positive benefits the industry brings to its local community and is the sort of real positive benefit you need to be telling people about  

Jan 1, 2000

By C. L. Brown

"INTRODUCTION The heavy loss of life from mine fires in some coal mines recently has focused attention on the importance of maintaining reliable communication systems between the active working sections of mines and the surface. A study of conditions following disasters in mines indicates that in several instances lives could have been saved if telephone communication had been available. Communication systems were not installed in some of these mines where disasters occurred, and in other mines they were installed in such a manner as to be rendered useless following a mine explosion or fire. Lives have been lost because of the inability of the rescue crews or persons di-recting the rescue to communicate with trapped men. Cases are known where many lives might have been saved had it been possible to give instructions for escaping or for location of barricades.More than 500 major disasters in which 5 or more lives have been lost have occurred in mines in the United States. The total number of lives lost in these disasters has exceeded 13,000. Some of the victims died instantly; but for many it was hours and in some instances days before death occurred. Evidence found in recovery operations following some of the disasters indi¬cates that many died needlessly because of the lack of suitable means of communication between the underground working areas and the surface.A localized gas and dust explosion in a coal mine in 1930 resulted in the death of 82 men; 2 were killed outright by the force of the explosion, 6 by a combination of burns and afterdamp, and 74 by afterdamp. About 140 men escaped or were rescued following the explosion, Of these, 119 escaped with little or no assistance, 2 were rescued promptly following the explosion, and 19 were rescued from behind a barricade. Seven bodies were re-covered from behind an ineffective barricade in another place; subsequent investigation proved that these men might have been guided to a safe location had an effective communication system been available."

Oct 1, 1946

By T. P. Williams, M. B. Rydzewski, B. Corner

Konkola Copper Mines (KCM) plc is an integrated copper producer operating on the Copperbelt in Zambia. KCM has numerous mining operations located in the towns of Chililabombwe (Konkola Mine), Chingola (Nchanga Open Pit and Underground operations), Lusaka (Nampundwe Mine), with a smelter located in Kitwe (Nkana Smelter) and an SX-EW plant in Chingola (Nchanga Tailings Leach Plant). [ ]

Jan 1, 2005

By Y. Z. Ma

This paper presents a matrix formulation of factorial kriging, and its relationships with simple and ordinary kriging. Similar to other kriging methods, factorial kriging can be applied to both stationary and intrinsic stochastic processes, and is often used as a local operator. Therefore, the concepts of intrinsic random function and local stationarity are first briefly reviewed. Kriging is presented in a block matrix form in which the kriging solution is useful not only for understanding the relationships between simple and ordinary kriging methods, but also the relationships between interpolative kriging and factorial kriging. When used as a signal/noise-filtering method, factorial kriging is especially useful for multiscale modelling. Examples for general signal analysis and geophysical data signal filtering are given to illustrate the method..

Jan 1, 2014

By J Wesseloo and Y Kim, Y Potvin, G Mungur, D Grant

At the previous MassMin conference held in Sudbury in 2012, the authors proposed a new framework going beyond dilution and equivalent linear overbreak sloughing (ELOS) for stope reconciliation in relation to the planned stope design. More specifically, the new process investigates performance outcomes including rock overbreak (OB) and fill overbreak (FOB), rock underbreak (UB) as well as geomechanical and operational aspects such as blasting, fragmentation and other production data.Based on the findings of the original 2012 study, a comprehensive data gathering program has been undertaken involving design and reconciliation data from 43 stopes mined between September 2012 and October 2014 at BHP Billiton’s Olympic Dam (OD) operation. The new database structure was based on four types of data:stope definition and performance datastope geometrygeotechnical parametersoperational parameters.The new database allows a more in-depth investigation of stope performance. It is now possible to quantify and analyse UB and OB performance from each wall individually as well as the crown. In this paper, the influence of several parameters on recent stope performance at OD is analysed. The underlying reasons for stope wall performance outcomes are discussed in this paper.CITATION:Potvin, Y, Grant, D, Mungur, G, Wesseloo, J and Kim, Y, 2016. Practical stope reconciliation in large-scale operations part 2, Olympic Dam, South Australia, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 501–510 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By Osamu Taki

This paper presents the system, the strength of column, the design concept, and the applications with four case histories from the past project as the general aspect of Geo-Column (trade mark of single soil-cement column by SCC Technology, Inc.). In the system, it shows the installation process and drilling/mixing tool with the mixing process. In the design concept, it shows how to design Geo-Column against the vertical and horizontal load. Finally, it shows the applications with four case histories, (1) building mat foundation, (2) isolated foundation on the pedestrian bridge, (3) bridge spread footing and slope erosion control wall in the channel, and (4) cut-off wall and shoring wall in the underpass roadway to the railroad.

Jan 1, 2000

By R. V. Ramani, W. Miola, R. Srikanth, S. C. Soboleski

"Dust control in high-production longwalls requires attention to operating practices and ventilation schemes. Several studies have shown that the shearer is the major source of dust on a longwall face. Support movement has not been regarded as a major source of dust in US longwalls. Yet, under certain conditions, 31% of the shearer operator's dust exposure can be due to support movement.Several methods have been developed for the control of shield-generated dust. But the need for better methods is apparent. In this paper, the amount of airborne, respirable dust generated per shield move is estimated from specially designed experiments on longwall faces. Ten experiments were conducted on five longwall faces in four mines. Each experiment involved one face visit and lasted three to six hours. The contribution of shield movement to the airborne, respirable dust concentration immediately downwind of the shield move varied between 0.12 and 1.75 mg/m3 in the five longwall faces. The mass of airborne, respirable dust gener-ated by shield movement was found to vary between 39 and 386 mg per shield move. The results from this study reveal that control of dust from longwall shields requires a combi-nation of approaches involving alternative operating prac-tices, reducing shield dust generation rate, increasing face air flow and decreasing personnel exposure.IntroductionIn 1992, longwall mining accounted for about 36% of US underground coal production, a 240% increase from a decade ago. The absolute longwall tonnages were 46 and 133 Mt (51 and 146 million st), respectively. Compared with room-and¬pillar mining systems, the longwall mining system is charac¬terized by higher recovery, enhanced safety and higher pro¬ductivity.However, personnel dust exposure on a longwall face is higher than in other types of mining. According to Mine Safety and Health Administration (MSHA) data, fewer longwalls were in continuous compliance with the applicable dust standard in 1992 than in 1989.Controlling shearer-generated dust and reduction of per-sonnel exposure to airborne dust have commanded attention in the design of longwall faces, operational practices and ventilation schemes. Studies in the United States and abroad have revealed that support-generated dust can be a major obstacle to compliance under certain conditions (Becker et al., 1989; Bradley et al., 1983; Jankowski and Organiscak, 1983; Jankowski et al., 1990; Organiscak et al., 1985)."

Dec 1, 1996

By D Craw, D Wilson, D Chappell

Gold is extracted by cyanidation of a sulphide-rich concentrate at Macraes mine, and after cyanidation, the concentrate is discharged to tailings impoundments. The concentrate tailings were discharged to a dedicated concentrate impoundment from 1989 to 1993, afterwhich they were blended with the flotation tailings. Since mid-1998, concentrate tailings have been redirected to the dedicated concentrate impoundment. The concentrate tailings contain up to 1 ppm gold, and will be reprocessed in the future. However, it is a regulatory requirement that a contingency plan be in place to rehabilitate the concentrate tailings should the mine operation cease for any reason. Initial predictions suggested that the sulphide-rich tailings would oxidise and acidify, creating a potential long term environmental problem. Investigations of the state of the tailings after 4 years show that these predictions were overly conservative. Only minor oxidation has occurred in the upper 2 metres of the tailings where the pH has locally dropped from 10 (discharge condition) to between 7 and 8. Below 2 metres, the tailings are essentially unchanged from their deposition state. The low rate of change in the tailings is due to their very low permeability which in turn is a consequence of the fine grain size (ca. 15 ¦m). Dewatering is extremely slow, and incursion of oxygenated water is negligible. Calculations suggest that water movement over 30 m will take at least 100 years and possibly 1000 years. The contingency plan is to capitalise on the very low permeability and keep the tailings from drying with a semipermeable cap. A layer of limestone will be added to the top of the tailings, beneath the cap, to enhance alkalinity of any percolating water. If acidification does occur, contrary to expectations, any acid produced will be neutralised by underlying calcite-bearing schist, schist in the concentrate impoundment wall, and the flotation tailings immediately downstream. In addition, dilution by alkaline ground and surface waters would further ameliorate any acidic discharge.

Jan 1, 1998

By H Matsuno, N Oyama, T Yamamoto, K Nakajima, Y Iwami, N Saito

Recently, the quality of sinter feed ore used in sintering process has deteriorated. In particular, Fe has decreased and gangue component has increased in the sinter feed ore. Increase of gangue is not only the factor to influence sinter qualities, but also the factor to increase coke ratio in the blast furnace operation as the increase of slag ratio. Therefore, to cope with the deterioration of iron ore qualities, studies on alternative iron ore resources and development of its utilisation technology have been required.In that kind of new iron ore resources, authors focus on high-grade magnetite fine. High-grade magnetite fine decreases sinter productivity by the decrease of permeability of sintering bed. Therefore a new study for using large amount of magnetite fine is required. In the past, there are some studies about the effect of mixing ratio and size of magnetite fine on productivity and quality, but there are few studies about magnetite fine segregation in charging.In this research, the melting behaviour and interfacial reaction calcium-ferrite, which has important role as bonding agent among iron ores, melts into hematite substrate and magnetite substrate was studied. As the results, it was defined that upper segregation of high-grade magnetite fine is suitable for productivity of sintered ore. Based on this knowledge, the control method of high-grade magnetite fine segregation by magnetic force at charging was studied with DEM (discrete element method) and its verification experiments for magnetic segregation control was conducted in the laboratory.CITATION:Iwami, Y, Yamamoto, T, Oyama, N, Matsuno, H, Saito, N and Nakajima, K, 2017. Improvement of sinter productivity by control of magnetite ore segregation in sintering bed, in Proceedings Iron Ore 2017, pp 61–68 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By L. Nahai

Overall mineral industry productive activity in Europe increased in 1965, following general upward trends in gross national product and total industrial production4 recorded. The gross national product of non-Communist Europe in market prices in 1965 was estimated at $572 billion and that of Communist Europe at $409 billion. However, the extractive sectors of the mineral industries generally did not fare as well as the processing sectors. In fact, a number of countries recorded lower production levels in this sector in 1965 than in 1964 and most countries had a lower growth rate in extractive industry output than in overall industrial output. Among the non-Communist nations of Europe, a general decline in coal production and lower levels of iron ore output in France, West Germany, and Luxembourg contributed significantly to the smaller growth rates or declines in extractive indexes. Where higher indexes were registered, this generally resulted from the performance of the petroleum and natural gas industry; exceptions were Greece, Norway, and Sweden. The decline recorded for Czechoslovakia was attributable entirely to poorer performance by that nation's coal industry.

Jan 1, 1967

By K. V. Raj

In the mining industry, computational fluid dynamics (CFD) modeling is used extensively to simulate air flow in underground mines. CFD modeling of pollutant transport in open-pit mines is relatively new. Modeling the actual pit geometry of an open-pit mine and the open domain is complex. The complexity is primarily due to the faceted geometry of an open-pit mine with its numerous associated sharp features. Important issues that are not considered carefully at the geometry level are generally propagated to the subsequent processes. Several challenges and pitfalls are encountered in modeling pollutant transport in open-pit mines. These challenges and pitfalls are related to the geometry, meshing, boundary conditions, and turbulence modeling parameterization. An appropriate mesh selection is critical. A detail discussion of the meshing of the domain of an open-pit mine is presented in this paper. The selection of an appropriate turbulence model, such as kappa-epsilon (?-e), large eddy simulation (LES), Reynolds stress model (RSM), etc., to obtain the best possible solution is equally significant. This paper discusses the various challenges in modeling the pollutant transport process in an open pit and some of the approaches adopted to address these challenges.

Feb 27, 2013

By Stan Henning

The monthly summary of the climatological record for the demonstration mine is presented in Table 1. Tear normal temperatures occurred throughout the growing season. From May to October precipitation was more than normal except in June when it was 2.55 inches below normal. Corn and soybean plantings were delayed until June 2-7 because of wet field conditions. This is about one month later than normal for corn planting. Insect infestations were much less than those encountered in previous years. Cutworm activity was not noticed and alfalfa weevil infestation were small and patchy. Stalk rot in corn was a significant problem at harvest and resulted in much Milk lodging. The wet and generally overcast conditions of July, August and September were bend 10 beneficial al to certain plant disease organisms. For example, pumpkins planted in a small garden area at the demonstration mine did not ripen because of a powdery mildew resulting from overcast, wet conditions. Field operations and row crop plantings were greatly delayed by wet field conditions. It was difficult to plant by conventional tillage because the soil remained soft and sticky where the moldboard plow had been used. Plots in the no-tillage system could he planted before conventionally tilled plots could be traversed. Plant emergence and plant density at

Jan 1, 1982