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By Harold Kennedy

Take a good look at this issue of Minerals and Materials. This is the last issue of M&M, as it has been known within the U.S. Bureau of Mines, that you will receive. Fifteen years after it was created to help cope with a growing worldwide mineral shortage, M&M is ceasing publication. In its place will be a bright, new publication called Minerals Today. Like its venerable predecessor, Minerals Today will be a bimonthly magazine that reports on recent trends and issues in the minerals and materials industries. It will be the Bureau of Mines' most frequent periodical presenting an overview of the entire field of minerals and materials.

Jan 1, 1989

By J Loimi, P Minkkinen, T Korpela

The head loss caused by metallurgical sampling for slurry streams can be reduced by metallurgical sampler design. When the process volumetric flow rate is reduced by vertical static cutters before the sampling by an equal number of moving cutters to the static cutters, the installation requires less installation head space than other sampling arrangements and is easy to accommodate at suitable locations in the process. Low head loss reduces building costs for the processing plant and operational costs during the lifetime of the plant.The presence of a possible systematic bias in the particle size distribution, solids density and elemental composition between an Outotec MSA 2/50 metallurgical slurry sampler sample and MSA 2/50 manually sampled reject have been studied by a customer. The paired samples were taken as simultaneously as possible. The customer evaluated the possible bias using a paired t-test and provided the assay results to Outotec for further evaluation.The results of the paired t-test showed no systematic bias in particle size distribution, solid density or assayed analytes, except in one analyte with low content and a high relative error. The high relative error in one analyte may have been caused by the same calibration model used in a X-ray fluorescence analyser for both high elemental-content concentrate and very low elemental-content tailings samples. The sampled stream is the tailings of a previous process stage.The results of the t-test were studied further using analysis of variance to reveal the error sources in samples. The results showed no bias between the samples collected from the MSA 2/50 reject and composite samples collected of the MSA 2/50 sample stream. The courier online analyser data was also available for evaluation of representativeness to the process stream.The analysis results of the courier online analysis reveals no bias between the MSA 2/50 reject samples, MSA 2/50 sample stream composite samples and online analysis results during the comparative sample collection period.CITATION:Loimi, J, Minkkinen, P and Korpela, T, 2017. Comparative evaluation of manual sampling and Outotec MSA 2/50 metallurgical slurry sampler, in Proceedings Eighth World Conference on Sampling and Blending , pp 167–172 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By P. James

Blue Planet Strategies (BPS) focuses on improved resource utilization and targets converting wastes into resources. New BPS capability (DEMET) wrings extra value from mining and processing wastes by enabling new production from waste and residual sources. This powerful platform technology provides considerable processing flexibility and enables various new economical treatment options to extract key metals from low level and process byproduct stream sources normally left as waste by traditional processing methods.[1]

Feb 23, 2014

By B Powell

Coastal acid sulfate soils (ASS) are wetland soils and unconsolidated sediments that contain iron sulfides which, when exposed to atmospheric oxygen in the presence of water, form sulfuric acid. ASS form in protected low energy environments such as barrier estuaries and coastal lakes and commonly occur in low lying coastal lands as Holocene marine muds and sands. When disturbed, the iron sulfides in these soils can oxidise and produce large volumes of sulfuric acid (essentially similar chemistry to acid rock drainage with mines) resulting in the subsequent release of toxic levels of iron, aluminium, manganese and possibly heavy metals. This results in detrimental effects on aquatic biota, plants, animals and steel/concrete structures and on human health in the surrounding environment. There are an estimated 2.3 million ha of ASS located along 6500 km of the Queensland coastline. In contrast to many mineral sulfides encountered in the mining industry, the pyrite crystals in ASS can be as small as 2 mm and commonly occur as framboids with extremely large surface area per unit mass, substantially increasing their reactivity if exposed to air (oxidation). Highly reactive iron monosulfides can also occur, particularly in drains and shallow lakes. Many coastal areas, where some 80 per cent of the population of Queensland reside, are coming under pressure for agricultural and urban development. Construction of canal estates, marinas, housing/industrial estates, roads, golf courses, aquaculture ponds, sand/gravel extraction and drainage for sugar cane can disturb ASS and release sulfuric acid, which may then drain into adjacent waterways with heavy rain. As development continues to encroach on coastal lowlands, the identification, quantification and management of ASS must be addressed as part of a commitment to the principles of Ecologically Sustainable Development (ESD). ASS can be successfully managed by adopting best practices and following guidelines, but government, community and industry must collaborate to raise awareness, avoid æhot spotsÆ and develop more cost-effective solutions. Scientists led the education and public awareness program showing infrastructure and environmental damages arising from ASS in Queensland. Using results from mapping and research, they convinced policy makers, industry and polititians to accept the need for legislation founded on good science. The resulting æState Planning Policy 2/02: Planning and Managing Development Involving Acid Sulfate SoilsÆ identifies the StateÆs interest in acid sulfate soils. The Queensland Government considers that development involving acid sulfate soils in low-lying coastal areas should be planned and managed to avoid potential adverse effects on the natural and built environment (including infrastructure) and human health. SPP 2/02 states where the policy applies and when a development application will trigger the policy. It can also be used to assist local governments in preparing their planning schemes under the æIntegrated Planning Act 1997Æ. The SPP 2/02 comes with a æState Planning Policy 2/02 GuidelineÆ to provide advice and technical information on interpreting and implementing the SPP 2/02. This guideline has legal status in assisting in the interpretation of SPP 2/02. Those seeking more detailed technical information can now also access the æSoil Management GuidelinesÆ and ASS æSampling GuidelineÆ, available from the Department of Natural Resources and Mines website. These are some of a series of chapters being developed for the æQueensland Acid Sulfate Soil Technical ManualÆ.

Jan 1, 2003

By R. Boom

Corus Umuiden, formerly Hoogovens, was the first steel plant in Europe after Voest to introduce oxygen steelmaking. In the decision-making process contacts with Dofasco in Canada about the production of formability steel grades were crucial. In developing oxygen (LD-) steelmaking high liquid steel output rates had to be combined with accurate process control. For ingot casting static models with input control and sampling during interrupted blowing were sufficient to deliver liquid steel within the required carbon, phosphorus, sulphur and temperature windows. Computers were introduced to perform the complicated charge calculations. Continuous casting called for strict control of composition and temperature at process end point and made predictable timing crucial. Dynamic control was introduced based upon sub lance measurements and waste gas analysis. Reliable disposable measurement sensors were developed in a concerted international action. Dissolved oxygen at blow end deteriorated the quality of low carbon aluminium killed steel grades. Blowing gases through the converter bottom improved process kinetics, resulting in lower carbon-oxygen products, yield increase and better phosphorus removal and generated new families of hybrid blowing processes. Introduction of secondary metallurgy facilities such as argon stirring stations, vacuum degassers and ladle furnaces relieved the demands for strict BOF end point control. Desulphurisation of hot metal became standard practice. In regions with scrap shortage hot metal desiliconisation followed by dephosphorisation, was introduced in the blast furnace cast house and hot metal transfer ladles. Later redundant converter vessels were used for pre-treatment, resulting in a two-stage process. The fundamentals of oxygen steelmaking are described and a vision on the future is presented.

Jan 1, 2004

A direct comparison has been undertaken between laboratory wind tunnel experimentation and computational fluid dynamics simulation of a 3D manufactured analogue for a body of fractured broken rock, created with CAD/CAM techniques. Detailed descriptions of the ?design? of the analogue (using a discrete element analysis multi-body simulator), its manufacture (using computer aided design and 3D printing technology) and the laboratory experimentation (inserting the physical analogue into a laboratory scale wind tunnel) are presented. The agreement of the results of direct experimental observations on the manufactured analogue with the values from CFD simulations of those experiments justifies the utilization of a CFD environment for the practical investigation of geometric factors controlling air flow and heat exchange in complex assemblages of broken rock blocks. The ultimate goal is described, that of developing functional relations between bulk properties of such assemblages (such as their porosity and bulk density) and the low-level geometric factors that dictate the air flow behaviour, such as the equivalent perimeter length of the cross-sectional area available for flow, or average flow path tortuosity. A practical application area of the work in the mining context is also described; equivalent continuum air flow and heat transfer constitutive models developed on the CFD tool from such functional relations are useful in characterization of seasonal heat storage in large scale bodies (approximately 1 km3) of broken rock.

Aug 1, 2013

By D. Harrington

Dust diseases are much before the public at present, but little reliable information on the subject is readily available to the layman; even those rated as experts usually have a more or less theoretical conception of these diseases, their causes, remedies, and prevention. Until recently little attention has been given to prevention, and the usual attitude of the engineer, upon whom the main reliance for prevention ultimately must devolve, has been to let "sleeping dogs lie" or, more definitely, to "let well enough alone." However, the "laissez faire" attitude no longer is tenable; in the past few years numerous conditions have caused those engaged in industry, including mining, to study the subject with a view to ascertaining the facts upon which to formulate remedial measures, primarily preventive. This bulletin is an attempt to assemble information in convenient form on effects of breathing dusts, largely in the mining and allied industries. The literature on this subject is so extensive that no attempt has been made to include all published material or all types of dust diseases but only to assemble some of the more outstanding data on several aspects of the subject, especially with reference to silicosis.

Jan 1, 1937

By P Cochrane

Our ability to generate information and transport it about the planet on super highways of optical fibre is about to change the way in which we communicate, work and live. There is not a single aspect of our future that will go untouched by the communication and computing revolution that Is now upon us. The change we are about to witness will overshadow the impact of the printed word, industrial revolution and physical transport. The next major wave of information technology (TT) development will focus on the delivery of information and experience on demand, in the right form, at the right time, at the right price, to fixed or mobile terminals anywhere, over networks of optical fibre, radio, satellite and optical wireless. Bandwidth, distance and time will no longer be significant cost elements as service and access become dominant.

Jan 7, 1996

By A. B. Cecala

Video technology coupled with data logging exposure monitors have been used to evaluate worker exposure to different types of contaminants. However, previous application of this technology used a stationary video camera to record the worker?s activity while the worker wore some type of contaminant monitor. These techniques are not applicable to mobile workers in the mining industry because of their need to move around the operation while performing their duties and tasks. The Helmet-CAM is a recently developed exposure assessment tool that integrates a person-wearable video recorder with a data logging dust monitor that are worn by a miner in a backpack, safety belt, or safety vest to identify areas or job tasks of elevated exposure. After a miner performs his or her job while wearing the unit, the video and dust exposure data files are downloaded to a computer and then merged together through a NIOSH-developed computer software program called EVADE (Enhanced Video Analysis of Dust Exposure). By providing synchronized playback of the merged video footage and dust exposure data, the EVADE software allows for the assessment and identification of key work areas and processes, as well as work tasks that significantly impact a worker?s personal respirable dust exposure. The Helmet-CAM technology has been tested at a number of metal/nonmetal mining operations and has proven to be a very valuable assessment tool. Mining companies wishing to use this technique can purchase a commercially available video camera and an instantaneous dust monitor to obtain the necessary data, and the NIOSH-developed EVADE software will be available for download at no cost on the NIOSH website.

Feb 27, 2013

By Daniel W. H. Su

A nearly 305-m- (1,000-ft-) wide sandstone channel was projected to run through the mid panel area of a 457-m- (1,500-ft-) wide longwall panel in a southwestern Pennsylvania coal mine. This sandstone channel was known to cause serious longwallface roof control problems in the mine?s B-panel area in 1998 and 1999; and most recently, it induced many large face cavities and caused a substantial production delay in the preceding panel. For the two B panels mined in 1998 and 1999, hydraulic fracturing of the massive sandstone was conducted to facilitate better caving, thus relieving cantilever compressive stress at the longwall face. Vastly improved longwall face condition was observed and four weeks of mining delay due to bad roof conditions were eliminated. The implementation of the hydraulic fracturing technique, results of underground observation and measurement, and results of numerical modeling were summarized in a paper presented in the 20th International Conference on Ground Control (Su et al., 2001). This article is a summary of the activities that took place during a four-month period (October 2011 through February 2012) at a Consol Energy longwall mine southwestern Pennsylvania to improve face conditions and safety of underground personnel during mining of the 457-m- (1,500-ft-) wide longwall panel. The elevated concern for safety was driven by adverse face conditions encountered while mining the preceding longwall panel. Many of the problems were attributed to a thick and massive sandstone channel. A joint task force consisting of coal operations engineering, Pennsylvania operations engineering and CNX Gas personnel was formed in August 2011, which recommended drilling four hydraulic fracturing holes along the center axis of the sandstone channel to reduce pressure and improve face conditions at the longwall face. To further provide detailed monitoring of the longwall face and to evaluate the effectiveness of the hydraulic fracturing program, the Longwall Visual Analysis (LVA) software (Hoyer, 2011) was installed in early December 2011 to track the face pressure and c

Jun 1, 2013

"Canada Centre for Mineral and Energy Technology (CANMET)Natural Resources CanadaMining and Mineral Sciences LaboratoriesA. Address and Contact Information555 Booth StreetOttawa, Ontario, Canada, KIA OGlWebsite: http://www.nrcan.gc.ca/Contact: Philippe Dauphin, Manager, Business DevelopmentTel.: (613) 947-0798Fax: (613) 947-0984E-mail: pdauphin@NRCan.gc.caB. Type and Size of FacilityScope of facilitiesCrushing from minus 4 in. to 10 mesh; grinding - rod, ball, vibration, SAG and impact mills; classification- screening, cycloning, mechanical, hydraulic and dry centrifugal classifiers; froth flotation - automated, column, and frothless flotation; gravity separation- wet and dry; magnetic separation - high gradient, high and low intensity, wet and dry; electrostatic separation; heavy-media separation; calcining; cyanidation; thickening; filtration; drying - fluid bed and freeze drying; pelletizing; microwave.SpecialtiesMineral beneficiation research and development; flotation of sulphides - flowsheet improvement, selectivity, reagent selection; novel flotation techniques; analysis of thiosalts formation; use of mineral processing techniques for recycling.Specialized equipmentHigh gradient magnetic separation, Denver XRF on-stream analyzer, automated flotation cell.Complementary support servicesElectron microprobe; SEM; STEM; X-ray diffraction; particle size analyzer; mineralogical and analytical chemistry services; physical chemistry; hydrometallurgy; pyrometallurgy; engineering and economic evaluation; mechanical shops; technical information services and library integrated with the National Library System of the National Research Council."

Jan 1, 2000

By E Widzyk-Capehart

The mines of the future can be envisioned as complex, large-scale technological systems being operated remotely from few centrally located (major cities) operating centres and skeletal crew stationed at the site. These systems will require remotely located human operators to constantly adapt to new and unforeseen system and environmental demands. In addition, the remote operators will need to match system properties to the changing demands and operational conditions, ie must be able to handle the ‘non-design’ emergencies, because the system designers would not have been able to foresee all possible scenarios of failures and provide automatic safety devices for every contingency. Therefore, it is highly important that the operators’ job, which involves problem solving and decision making at the workstation level, is facilitated by the proper interface designs. This paper argues that decision support systems and thus human-system interfaces for the mines of the future should be developed based on the principles of human-system integration that take into account human information processing and cognitive abilities. The information presented to the operator must support the operator in taking appropriate action through a human-system interface designed according to scientific principles of User Centred Design. A case study is presented where an iterative design process was used by CSIRO researchers as an evaluation method involving users (control room operators) at several stages of the user interface design in order to correct any design inadequacies as they emerged. This process allowed the designers to identify any usability issues before the user interface was fully implemented, which subsequently enabled the control room operators to easily adapt to the new interface and carry out all designated tasks in a timely and effective manner.

Nov 22, 2011

By Scott G. Britton

Mine exploitation is a broad subject whose focus is the technical skills or efforts needed for the extraction of mineral from a known ore body. Mine exploitation can be considered the very core of the mining engineering discipline. It begins at the conclusion of the exploration and development stages of mining and ends when the ore body is exhausted and the mine (or mines)closes and is reclaimed. Section 8 on mine exploitation is comprised of seven chapters: (1) classification of mining methods, (2) mine surveying and mapping, 3) systems engineering, (4) computer methods, (5) labor relations and training, (6) management and administration, and (7) mine closure, sealing, and abandonment. Each chapter focuses its efforts towards providing detailed and useful information for the engineer on basic mine exploitation principles. The information can be applied to a broad range of mining problems without regard to mineral type or mining method.

Jan 1, 2008

By Tad S. Golosinski

The paper describes Online Master of Engineering Program at the University of Missouri-Rolla and discusses the experience gained during the first three years of its offering. This innovative educational program is designed primarily for mature students with an engineering or science background who want to acquire or upgrade their knowledge of mining engineering. Students can specialize in several different areas of mining, such as surface mining, underground mining, mine environment and the like. All courses constituting the program are taken online, through the Internet, without the need to attend the UMR campus in person.

May 1, 2004

By Joseph H. White, DR. JAMES G. CUMMING

This report presents the results of an investigation of hookworm infection in the deep gold mines of the Mother Lode, California. In this investigation 1,440 miners of the Mother Lode have been examined for hookworm infection; 444 miners were found to be infected; and 91 miners have taken the treatment and have gotten rid of the infection. ·Within a short time after this preliminary examination, an industrial strike started, which gradually scattered the miners and made it difficult to institute the treatment of many of those who had been found infected. ·With the completion, however, of the State survey all these will eventually be identified and treated. In 1906 Dr. F. F. Sprague, of Jackson, Cal., and formerly of the Philippine Islands, recognized the prevalence of hookworm infection in the gold mines of California. He treated many cases of the infection and brought the prevalence of the disease to the attention of his colleagues. Following closely this pioneer work of Dr. Sprague was that of Dr. E. E. Endicott, health officer of Amador County. In 1911 Dr. Endicott a related his experience in a paper before the American Medical Association. In 1909, Dr. Herbert Gunn, under the auspices of the California State Board of Health, made an investigation to determine the prevalence of the disease among miners. b He reported on the blood and stool examinations of groups of men from three large mines in Amador County. The high eosmophilia verified by stool examinations in many of the cases, and the demonstration of larvae in soil from the workings led Dr. Gunn to the following conclusions: 1. Hookworm disease is endemic in certain mines of California. 2. From 50 to 80 per cent of those working in these mines are infected. 3. The infection undoubtedly is present in practically all the gold mines of California and in those of Nevada just over the border. vYhen it was definitely determined by the California State Board of Health to make an investigation, in cooperation with the Industrial Accident Commission of the State of California and the Federal Bureau of Mines, as to the prevalence of hookworm infection among the miners of California, the following procedure was planned: (1) To encourage the superintendents of the various mines to cooperate in the campaign; (2) to diagnose fecal specimens from the miners and determine the percentage of infected miners; (3) to reach an agreement with the superintendents that all infected men must be treated; (4) to make reexaminations of all treated men; (5) to issue "hookworm certificates"; and (6) to eventually reexamine all California miners. A visit to several of the mines on the Mother Lode made it evident that the mine operators would cooperate most cordially in this campaign; in fact, several superintendents had already considered the advisability of such an undertaking.

Jan 1, 1917

The Full Scale Model Roof Bolt Test System described herein was designed, fabricated, erected, and installed by MSA Advanced Systems Division for the U. S. Department of Interior, Bureau of Mines, Spokane Research Center. It was furnished under USBM Contract No. 50271014 and Modifications. The test system is intended for use by the Bureau of Mines to run comparison tests on roof bolt systems. The mine entry cross section is made from special concrete pillars and roof slabs. They are constructed within a steel beam frame with hydraulic operated cylinders to apply loads that simulate the action of mining overburden. The frame is designed so it can be disassembled for replacing the concrete in subsequent tests. A computer and data acquisition system is furnished to control the load application and measure and gather data.

Jan 1, 1979

By Heber E. Peterson, Sill. Claude W.

"INTRODUCTION In the usual volumetric determination of uranium, the solution containing uranium is reduced in a Jones reductor, yielding a mixture of trivalent and tetravalent uranium; the trivalent uranium is oxidized to the tetravalent state by bubbling a stream of air through the solution. The resulting solution of tetravalent uranium is titrated with a standard oxidant, generally sulfatoceric acid, dichromate, or permanganate. It seemed likely that the same general procedure could be used in determining semimicro quantities pf uranium if the conditions affecting the variables involved were understood more clearly than at present. In the method described below, the use of ferric sulfate to oxidize tetravalent uranium allows the titration to be made at room temperature in an essentially colorless solution with sulfatoceric acid. The latter oxidant in turn permits the use of the very stable indicator, ferroin; with its sharp color change and exactly reproducible blanks.Solutions of uranyl sulfate were prepared by diluting a stock solution that had been standardized gravimetrically according to the method of Lundell and Knowles (8).3/ Solutions of sulfatoceric acid were prepared according to the directions of G. F. Smith (12) and were standardized against arsenic trioxide in the presence of osmic acid according to the directions of Glen (5). The cerium solutions were stored in 18-liter carboys fitted with siphon arrangements so that the bottles did not need to be opened and protected from light in a dark cupboard. Under these conditions, even the 0.01 N solution changed by less than 1 part per thousand over a period of about 6 months."

Jun 1, 1952

By Adrian Coombs

The York Durham Sewage System (YDSS) Interceptor Tunnel Project is located in the Town of Richmond Hill, Ontario, Canada, just north of Toronto. Construction commenced in September 2006 and completion is planned for early summer, 2008. The project involved public and agency buy-in of construction technologies and methods that minimized dewatering, design and construction of sealed shafts with jet grout break-in and out blocks in order that Earth Pressure Balance (EPB) mode could be maintained by the Tunnel Boring Machine (TBM) during shaft entry and exit. This paper will discuss the advances that were made possible through the opportunity to apply and test these technologies in order to accommodate the aquifer and artesian conditions present on this project.

Jan 1, 2008

By J. E. Johnson

IT is the purpose of the present paper, while not excluding chemical considerations, to deal more extensively with some of the physical and mechanical aspects of the blast-furnace process, and to point out its dependence in these respects on well-known laws. The quantity and cost of ore and flux required to make a ton of iron being determined by circumstances over which the furnace-man, under given conditions as to quality and quantity of product, has commonly little control; the principal item of cost, apart from the saving of labor, which he can aspire to reduce, is that of fuel. To determine the limits of possibility in this direction is clearly the first step in d practical inquiry; and this step is represented herewith in Fig. 1, a diagram showing the total useful effect obtained from a pound of fuel under various conditions, and thus permitting direct comparison, under any given conditions, between actual results and the maximum possible results. The following statements will explain the basis upon which this diagram has been constructed. One pound of fuel, containing 90 per cent. of fixed carbon (which represents average conditions), is taken as the unit. The degree of oxidation of the carbon is measured by the ratio of the two oxides of carbon contained in the top-gases. It is necessary to remember that a considerable quantity of carbon is brought in as carbon dioxide by the flux, and to take account of it and of its condition. It is here considered that the carbon dioxide liberated by the limestone does not affect the analysis of the toll-gases, and that the ratio of CO to CO., will remain unchanged by the addition of limestone; enough CO, being reduced by the solution

Sep 1, 1905

By Agne Rustan

This paper is intended to give a summary of the first ten Symposia on Rock Fragmentation by Blasting where the symposia activities were governed by a Steering Committee replaced at Fragblast 2 by an International Organizing Committee (IOC). At Fragblast 9 the name was changed to Fragblast International Organizing Committee (FIOC). Eighty four pages of statistical data about Fragblast 1-10 is documented on the Fragblast Website (ISEE.org).

Jan 1, 2014