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By W. S. Weldon, R. M. G. Machunter

The use of spiral separators for the beneficiation of fine coal typically in the size range - 2+0.lmm is now well established process technology. Developments during the mid 1980's resulted in the production of cost effective, efficient large diameter coal spiral separators. Recent developments and research have been geared to optimise metallurgical performance, materials handling and equipment geometry of large diameter coal spiral separators.

Feb 24, 1997

Some low grade South Australian iron ores were classified on the basis of their physical characteristics. Ores from Mount Christie and Billeroo are coarse grained mixed ores; Mount Christie ore could be concentrated by gravity or dry magnetic separation at 10 mesh, but Billeroo ore needed to be crushed minus 36 mesh. Ores from Razorback Ridge and Wilgena Hill are fine grained mixed ores; ore from Wilgena Hill could be concentrated by flotation, but poor results were obtained on Razorback Ridge ore. Malcolm Creek ore is non-magnetic and crystalline, and can be concentrated by flotation, but the deposit is small. Ores from Grants Quarries and Peeralilla Hill are nonmagnetic and earthy and could not be satisfactorily concentrated.INTRODUCTIONThe Geological Survey of South Australia has for several years been undertaking a systematic study of the iron ore resources of the State (excluding the Middleback Ranges) in relation to their geology, reserves, and beneficiation. As part of the latter phase of the investigation samples of the ores have been submitted to The Australian Mineral Development Laboratories (AMDL), and it was the study of these samples which provided the material for this paper.The mineragraphic and metallurgical work was undertaken by several officers of AMDL and the results are contained in unpublished reports submitted to the South Australian Department of Mines. Field data published here was obtained from unpublished reports by G. F. Whitten, Senior Geologist, Iron Exploration, of the Geological Survey of South Australia.

Jan 1, 1964

This report is the 25th in a series summarizing Bureau of Mines research and technologic work on coal and related investigations, and the 7th of these reports to be issued on a calendar-year basis.3 It reviews briefly work in progress during 1960, and furnishes references to publications by Bureau personnel during 1960 and also to a few older papers that were not cited in prior reports of this series. Details about some of the researches mentioned can be found by referring to the publications cited in the footnotes or in the further list in the Miscellaneous section; other phases of work are reported here for the first time and will be covered in more detail by later publications, Coal programs of the Bureau of Mines extend over the wide range of theoretical and applied studies indicated by the table of contents. Fundamental research on coal structure and on the properties of coal will, over a period of time, increase the general knowledge about coal Which scientists and engineers may use in answering practical questions and in solving problems in the mining and utilization of coal. More applied studies are conducted in connection with the developement and evaluation of new mining techniques and the effective processing and utilization of coal and of coal products. Health and safety activities, analyses of coal being mined, and technical advice and assistance to Federal agencies in connection with fuel and boiler-water problems are among the practical services handled by the Bureau.4 5

Jan 1, 1962

By D. Randolph Berry

The United States Bureau of Mines (USBM) awarded a contract to Foster-Miller, Inc. to develop guidelines for the storage and use of Self-Contained Self-Rescuers (SCSRs) in underground non-coal mines. An SCSR is a device capable of supplying, in an emergency, one hour of self-contained oxygen (no breathing of mine air). The information and recommendations in this report were developed primarily from three sources: discussions with mine representatives (including management, labor, and government), site visits in underground mines I and a detailed analysis of every reported non-coal accident which produced d hazardous atmosphere during the 5-year period 1976-1980 -plus ten other major incidents from prior years. Volume IV has three major sections: Recommendations and Discussion (Section 2), Analysis of Mine Accidents (Appendix A), and a Summary of Discussions with Mine Representatives (Appendix B).

Jan 1, 1983

By O. Kangal

Flame retardant materials can be incorporated or applied to products, including plastics and textiles, to increase their resistance to fire. Incorporating a flame retardant in combustible materials and plastics is a common procedure to reduce the risk of fires. Flame retardant applications include interior and exterior woods, structural steel columns, fabrics, open and closed cell foam, pressure treated wood, Formica and all types of fabrics for use in commercial applications as well as residential applications where their fire protection products can save lives and valuables. Huntite and hydromagnesite are amongst the most important flame retardant additives materials. Although various areas of the world have potential huntite and hydromagnesite deposits, their place in industry is not well known, and a detailed field search for their deposits has not yet been conducted. They are active during the starting phase of a fire, in that they prevent the spread of an inner or exterior source of ignition to the flame-retarded material, thereby, preventing, delaying or inhibiting the spread of a fire. Flame-retardants are, therefore, just one element among many in a concept for preventive fire safety. To obtain huntite and hydromagnesite concentrates that are more than 95% pure, which are used in flame retardant industry, flotation tests were conducted on low-quality huntite and hydromagnesite ores.

Jan 1, 2009

By Mario A. Terceros H., K. Rainer Massarsch

"ABSTRACTThe Expander Body (EB) technology has been used successfully to increase the pile toe capacity of bored piles in loose to medium dense soil. An important advantage of the EB system is the ability to monitor the EB expansion process, which provides important information regarding soil strength and soil stiffness. This information, obtained for each installed pile, can be used to determine the actual shape and pile toe area. The expansion pressure can be used to design the pile base capacity.The Expander Body system has been recently improved by incorporating the possibility of post-grouting of the soil below the expanded pile toe. This improvement measure provides additional strength and stiffness to the pile toe and reduces pile settlement.The shaft bearing capacity of bored piles can be increased by using a soil displacement auger, which avoids soil decompression and increases lateral soil stress. This paper describes the principle of the EB system. During the past 20 years, a large number of EB piles have been installed in Bolivia and elsewhere, providing a sound database. Results from field loading tests are presented. A comprehensive study of test piles with and without EB base has been carried out which demonstrates the improvement effects that can be achieved by the EB pile system and the combination with the displacement auger pile method. A design concept for the EB pile system with the full displacement auger pile is presented. A high degree of quality control can be achieved by monitoring the entire pile installation process, including the displacement pile and the Expander Body.1. IntroductionIn many regions of South America, soil deposits consist often of predominantly loose to medium dense sands and silts, often with high groundwater table. In the Santa Cruz area in central Bolivia, such soils are frequently quaternary sediments, deposited by the river Piray. The city of Santa Cruz is located at the right bank of the river.The most common deep foundation method during the last 30 years has been cast in situ piles, augered and concreted under support of bentonite slurry. The design of such piles has been based on SPT results. However, SPT is often performed without quality control and the reliability of geotechnical data is therefore often poor. Traditional methods of pile installation with simple well drilling equipment of insufficient capacity are frequently used. Such methods lack basic requirements of quality control. Such piles have usually low toe resistance and work mainly by shaft resistance . Although the construction process and materials are cheap, the final product has variable and limited capacity. However, the most serious deficiency is that actually achieved pile capacity and pile settlement can be erratic and difficult to predict, leading to uncertainties with regard to actual foundation performance."

Jan 1, 2014

By J. L. Viljoen

t has long been the drive of the industry and all operations to create an environment that is free of injury and illness. We have come a long way; the leaders, executives, managers, supervisors and workers are to be commended for relentlessly driving to create, what I call a ?White Flag Day Every Day?. Yet I am also aware of the huge shift we still need to create in the industry, on the operations and in the workplaces to have them free of injury and illness. Keywords People, values, care, trust, belief.

Jan 1, 2011

By Scott Rosenthal, Kyle Murphy

This paper discusses the trials and tribulations of obtaining Velocity of Detonation (VOD) readings in small diameter blast holes in an underground mine. Montana Technological University (Montana Tech) obtained a time-domain reflectometer (TDR) type VOD monitoring unit. Purchase of the VOD monitor was justified on verifying explosives performance used in Montana Tech’s practical underground mining class and provide a teaching aid for the school’s rock fragmentation class. Before demonstrating the unit to students, we figured we better learn how to use it first so we give the students an appropriate experience. Our first learning was in obtaining the correct coaxial cable for the VOD monitor and how to properly terminate the cable. Once the cable was on-site and terminated, VOD testing could commence. Use of the VOD monitor was tested underground in small diameter holes (1.5-inch, 38 millimeter) pneumatically loaded with ANFO. After a few failed trials, and follow-up discussions with the supplier, VOD readings were obtained for the ANFO loaded holes. Additional readings were obtained for a pre-split product and detonating cord to satisfy our curiosity that the unit was performing as specified by the manufacturer. This paper will share our learnings in the hopes that others can benefit.

By Gorr W. W., Wyche E. H, R. Smith

The combination of high strength and corrosion resistance of cold-worked 18 Cr, 8 Ni steel has been advantageously utilized for some time, particularly in aircraft and rail car structures. There are, however, certain limitations on the use of such materials because the high strengths can be obtained only by cold-working, limiting the available products to sheets, strip, wire and tubes. The authors sought to overcome these limitations by resorting to precipitation-hardening, which has been used so successfully in nonferrous metallurgy but only to a limited extent in iron-base alloys. Accomplishment of this objective not only overcame the limitations, but also effected certain improvements in mechanical and other properties. This paper is an account of the development by Carnegie-Illinois Steel Corporation of a precipitation-hardening 18-8 stainless steel (called Stainless W‡ and tentatively identified as type 322). A description is given of its composition and metallurgical characteristics, heat-treatment, physical and mechanical properties and corrosion resistance. Development of the New Steel For a considerable length of time the authors were unable to determine the mechanism of the precipitation-hardening process that had been noted by Ffield18,19 in 18-8 Ti or 18-8 Cb after cold-working and reheating to moderately elevated temperatures. All known variables were exhaustively studied, but with little success. However, results began to indicate that chemical composition was the most important variable, particularly the ratio of austenite-forming to ferrite-forming elements. The investigators then focused their attention upon the composition, and, in particular, upon the element titanium and its mode of alloying in the presence of other elements. A heat was obtained that could not be brought to the softness level of annealed 18-8. The response to cold-straining and aging* was very marked by previous standards, and, more important, cold-straining was found to be entirely unnecessary to produce the precipitation-hardening effect. The chemical composition of this heat was: C, 0.06 per cent; Mn, 0.54; P, 0.016; S, 0.016; Si, 0.58; Ni, 7.28; Cr, 17.60; Ti, 0.90; Al, 0.17. For some time the development work, particularly on composition, was carried

Jan 1, 1947

By Gorr W. W., R. Smith, Wyche E. H

The combination of high strength and corrosion resistance of cold-worked 18 Cr, 8 Ni steel has been advantageously utilized for some time, particularly in aircraft and rail car structures. There are, however, certain limitations on the use of such materials because the high strengths can be obtained only by cold-working, limiting the available products to sheets, strip, wire and tubes. The authors sought to overcome these limitations by resorting to precipitation-hardening, which has been used so successfully in nonferrous metallurgy but only to a limited extent in iron-base alloys. Accomplishment of this objective not only overcame the limitations, but also effected certain improvements in mechanical and other properties. This paper is an account of the development by Carnegie-Illinois Steel Corporation of a precipitation-hardening 18-8 stainless steel (called Stainless W‡ and tentatively identified as type 322). A description is given of its composition and metallurgical characteristics, heat-treatment, physical and mechanical properties and corrosion resistance. Development of the New Steel For a considerable length of time the authors were unable to determine the mechanism of the precipitation-hardening process that had been noted by Ffield18,19 in 18-8 Ti or 18-8 Cb after cold-working and reheating to moderately elevated temperatures. All known variables were exhaustively studied, but with little success. However, results began to indicate that chemical composition was the most important variable, particularly the ratio of austenite-forming to ferrite-forming elements. The investigators then focused their attention upon the composition, and, in particular, upon the element titanium and its mode of alloying in the presence of other elements. A heat was obtained that could not be brought to the softness level of annealed 18-8. The response to cold-straining and aging* was very marked by previous standards, and, more important, cold-straining was found to be entirely unnecessary to produce the precipitation-hardening effect. The chemical composition of this heat was: C, 0.06 per cent; Mn, 0.54; P, 0.016; S, 0.016; Si, 0.58; Ni, 7.28; Cr, 17.60; Ti, 0.90; Al, 0.17. For some time the development work, particularly on composition, was carried

Jan 1, 1947

By Kadri Dagdelen

Design of the ultimate pit limit to direct long range mine planning has been a celebrated problem in the mining industry, and in mining academia, since 1965. Although many papers have been presented on this topic, even today, there is not a single solution technique which is widely accepted and considered universally best. Many philosophical differences exist among the pit planners concerning the use of different methods and it appears that resistance is very strong towards accepting other techniques if you are a believer in one. Whatever the case might be, the pit parameterization technique for the ultimate pit limit design is the latest and takes a different approach than its predecessors. There are already a number of papers which discuss the concepts involved (Francois-Bongarcon, 1976; 1978; 1980; 1981); however, the aim of this paper is to fill in some of the gaps which are thought to be missing in the previous discussions and, in addition, to present the recent research done on the subject at the Centre de Geostatistique de l?Ecole de Mines de Paris in Fontainbleau, France. This paper is divided into two parts. The first part will discuss practical aspects and interpretations of pit parameterization concepts with- out using mathematical or theoretical arguments; the reader who is interested in the theory should refer to Francois-Bongarcon (1978). The second part will present an approach to obtain a complete double parameterization of reserves using an inexpensive (computer costs) single parameterization algorithm. A case study of this approach is also included.

Jan 1, 1982

By L. R. Raymond

With the trend toward deeper and consequently hotter holes, measurements of drilling mud properties at atmospheric temperatures are becoming increasingly inadequate.' Both the prediction and control of down-hole mud properties depend in part upon our knowledge of temperatures in the wellbore. Consequently, a better understanding of factors that affect temperatures during circulation and trips could improve drilling operations. It was toward the goal of obtaining this understanding that this study was directed. Other investigators2 have studied the response of fluid temperature in the borehole during trips. However, all of these studies have used an assumed formation temperature profile at the conclusion of circulation and have provided no means to calculate this profile directly. In this study, the formation profile during circulation was calculated. Other investiga-tors3-5 have also studied bottom-hole temperature during circulation. However, they have developed neither general techniques for calculating the entire temperature profile in the system nor generalized methods for predicting bottom-hole fluid temperatures during circulation. Such techniques and methods have been developed and are discussed briefly in the following pages. Temperature Behavior During Circulation Circulation of fluid during the drilling operation is represented schematically in Fig. 1. The process of circulation has three distinct phases: (1) fluid enters the drill pipe at the surface and passes down the drill pipe; (2) fluid exits the drill pipe through the bit and enters the annulus at the bottom; and (3) fluid passes up the annulus and exits the annulus at the surface. To simulate the thermal behavior of the fluid in the system, each of the phases of circulation must be described mathematically. In Phase 1, the fluid enters the drill pipe at a specified temperature, TDo. As the fluid passes down the pipe, its temperature is determined by the rate of heat convection down the drill pipe, the rate of heat exchange between the drill pipe and the annulus, and time. Phase 2 of the circulating process merely requires that the fluid temperature at the exit of the drill pipe be the same as the fluid temperature at the entrance of the annulus; i.e., TD(L,t) = TA(L,l). Thus in Phase 3, the fluid enters the annulus at TD(L, t). As the fluid flows up the annulus, its temperature is determined by the rate of heat convection up the annulus, the rate of heat exchange between the annulus and the drill pipe, the rate of heat exchange between the formation adjacent to the annulus and the fluid in the annulus, and time. These rates of heat exchange and the time dependency of mud temperature are described by well known heat-flow equation.6 Consequently, as shown in the Appendix, the temperature profiles in the drill pipe, annulus, and formation can be obtained by solving Eqs. 1 through

Jan 1, 1970

By John C. Machisak

INJURY and employment figures for nonmetal mines and mills in 1959 are presented in this publication. Data for nonmetal mines are presented separately from those for nonmetal mills. The Bureau of Mines is authorized to send questionnaires to the nonmetal mining industry each year requesting their voluntary submission of injury experience and employment data. The voluntary response to these requests has contributed greatly toward the promotion of safety in the industry, and every effort has been made to make the information as complete as possible.

Jan 1, 1963

By Stephen L. Chryssoulis, Stamen Dimov

"Preg-robbing has been known for many years, where increased losses are suffered because dissolved gold is removed from solution by adsorption onto carbonaceous matter. In direct cyanidation circuits it is reasonable to conclude that the preg-robbed gold is either in a gold cyanide [Au(CN) - 2, AuCN] or metallic [Au°] form. However, in circuits with a pre-oxidation step possibilities increase and multiply even further because of water recycle streams containing apparent and not-so-apparent gold ligands. It is in these circuits where speciation of sorbed gold, i.e. the identification of the gold compound, is useful. The importance arises from the fact that proper identification of the sorbed gold species can be used to determine how, when, where and why gold was removed from solution, thereby identifying the exact cause of the problem and providing clues as to how it may be rectified.INTRODUCTIONTo the best of our knowledge, this is the first attempt ever to speciate gold preg-robbed by carbonaceous matter using a surface sensitive microbeam technique. This approach enables the direct determination of gold species sorbed on carbonaceous particulates, opening an entirely new field in the understanding of the chemistry of gold sorption on carbon. The reasoning behind this effort was to add to the current knowledge of the detrimental effect chloride ions have on gold recovery by the pressure oxidation and in particular why in the ensuing CIL step, gold is not being desorbed from the surface of the carbonaceous particles (Table 1)."

Jan 1, 2004

By R. A. Jankowski

The U.S. Bureau of Mines (USBM) conducted a series of laboratory tests to investigate the effectiveness of using a flooded-bed scrubber with exhaust ventilation in deep-cut faces of up to 12.2 m in length. An experimental test program to determine the impact on respirable dust levels resulting from changes in face airflow, curtain setback distance, operator positioning, and operating parameters of the external spray system on the miner was completed. Gravimetric sampling was conducted in the immediate return and at three sampling locations on the off-curtain side of the entry. Statistically significant differences in dust levels on the order of 0.5 to 1.2 mg/m3 were observed between specific sampling locations and changes in several test parameters. Dust sampling results indicated that a flooded-bed scrubber and exhaust ventilation can be a viable dust control system for extracting deep cuts up to 12.2 m in length. The impact on methane was not evaluated.

Feb 24, 1997

Ore sorting is a high capacity, low cost method of pre concentrating ores and in some cases of producing a marketable concentrate. In most cases it is applied to run of mine material, immediately after primary crushing and screening in sizes ranging from 10 mm to 150 mm. Recent developments in bulk sorting of friable uranium deposits have resulted in machines capable of handling fine materials with sensing and separation being achieved on a zone by zone basis. Modern ore sorting machines rely on the synchronous operation of four internal subsystems, feed presentation, sensing, data processing and separation. A variety of different sub systems is available which can be combined in various forms to produce sorters capable of handling a wide variety of mineral types. The benefits in using ore sorting cover a wide range of situations and are applicable to both established mines as well as new mining ventures. Reduced operating costs, increased productivity, capital savings, energy and resource conservation and environmental issues are all part of the reason why ore sorting is finding rapid acceptance in today's mining industry. The suitability of different ore types for pre-concentration using anyone of the variety of ore sorting systems can be quickly established using computer based techniques which require only small samples of the materials under investigation.

Jan 1, 1980

By S Worden, P A. Kirsch, A Kirsch

Despite the current downturn, coal remains an important commodity in the Australian economy. Increasing coal resource development has resulted in increasing competition for land use in coal mining regions across the country with communities and other stakeholders becoming more adept at articulating their concerns regarding this competition in a range of traditional and social forms of media. In this environment, obtaining and maintaining a social licence to operate (SLO) is problematic and has been identified as the fourth greatest risk facing the international mining industry.This research presents the findings from a longitudinal study on how Australian newspapers frame the views of coal mining stakeholders across each stage of the coal mining life cycle. News stories from national, state and regional newspapers in 2000, 2006 and 2013 were analysed.Over the study period, there have been significant changes in the coal mining themes being covered by Australian newspapers, the number of stories being published, the number of newspapers covering coal mining stories, and the diversity of stakeholders being quoted. How do the dominant themes in media communication change over time? How do these changes impact mining across the life-of-mine?The research confirmed that Australian journalists use framing, priming, labels and bias to conceptualise and understand the events that they report, and that this behaviour has a profound effect on public opinion.CITATION:Worden, S, Kirsch, A and Kirsch, P A, ?2014. Moving beyond economic framing of the Australian coal industry, in Proceedings Life-of-Mine 2014 , pp 365–376 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By M Rafty, A Markham, S Atkinson, M Heyting

Over recent years there has been a significant increase in the number of miners in the Pilbara region of Western Australia targeting channel iron deposits (CID) located in valleys, intersected by ephemeral creeks and below the groundwater table. The falling iron ore price has triggered a drive to reduce cost and maximise yield. Creek diversions provide an opportunity to maximise the utilisation of orebodies and extend the life-of-mine.Creek diversions that are required during mining operations to access ore and provide flood protection have historically been constructed as uniform engineered channels designed primarily for flow conveyance while minimising earthworks costs; however, the design of diversions becomes more complex when they are required to function in a similar way to the existing creek system during operations and remain stable during more extreme events than would typically occur following mine closure, in accordance with current regulatory guidance. The design specifications for closure are often more rigorous than the operational phase, and could incur significant additional cost to implement retrospectively if not planned and designed upfront.The complexity of diversion design depends on site specific factors such as: the size of the creek to be diverted; hydrology; corridor restrictions; geomorphology; hydrogeology; geology; environmental and heritage values; potential impacts and the risk to operations and environment. The complex interactions of these factors must be well understood and hydraulic modelling undertaken to characterise the existing creek system, demonstrate the diversions, provide adequate flood protection during operations, and can function in a similar way to the existing system following mine closure. This paper presents key design considerations for Pilbara creek diversions, operational and closure requirements, mine planning considerations, risks, cost saving opportunities, and the benefits of an integrated approach to design.CITATION:S Atkinson, A Markham, M Rafty and M Heyting, 2017. ‘Back to the future’ – resilience in historical context and implications for the future, in Proceedings Iron Ore 2017, pp 367–374 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

The greater part of this paper comprises the material used in a lecture delivered to the South Queensland Branch of the Australasian Institute of Mining and Metallurgy in September, 1949. It contains little in the way of original matter, its main purpose being to call attention to the need for research into the properties of Queensland coals and to indicate some of the lines such investigations might profitably follow.Since the lecture was given the Powell Duffryn (1949) 1 report, which has made an excellent start along these lines, has been printed. This report is, however, only a beginning, though a big one, and there is ample room for many years of work along similar lines.The paper is based largely on the work of de Jersey (1946, 1949)2,3,4,5 and Jones and de Jersey (1947)6, but these workers in turn owe a debt to the work of many British and American investigators, too many to enumerate. The subject is a very large one-to deal with it fully would require not a paper but a book; all the author can hope to do is to discuss very briefly some of the main lines of investigation and indicate some of their applications.The reason for selecting Queensland coals in particular is the widespread ignorance of the extent of the coal resources of that State and the almost complete ignorance, to within the last year, of the modern industrial purposes to...

Jan 1, 1950

By Timothy P. Smirnoff, Tracy K. Lundin

INTRODUCTION The City of Phoenix, Arizona is located in the Phoenix Basin watershed which is prone to flash flooding several times each year. The runoff from these storms moves from the mountains in the north to the Salt River in the south. An extension of Interstate Highway 10 (1-10) will pass through the city east to west to form an Inner Loop through the downtown business district. PROJECT DESCRIPTION The I-10 Inner Loop extension will be a depressed roadway which would intercept the surface drainage of the Phoenix Basin and separate the watershed into two regions. To prevent flooding of the depressed roadway, runoff storm water collected from the northern half of the drainage area will be conveyed beneath the roadway to its natural outlet at the Salt River. A conveyance system composed of pressure tunnels beneath the city, shown in Figure 1, was proposed to achieve this goal . Table A presents the prominent features of each of the tunnels. This paper will describe geologic and engineering parameters specific to Phoenix which were used in the design of a series of tunnels to convey storm water from the I-10 Inner Loop to the Salt River. The design of tunnel initial and final support is described along with support and construction methods used by the Contractor.

Jan 1, 1985