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By D. G. Champion

"A comparison of diesel engine power ratings with in-service capability, and the selection of unit size and total number of units are discussed in the paper. Engine specific fuel consumption and its evaluation in relation to manufacturers' tolerances and equipment load factors is reviewed along with the suitable plant layout. The potential for heat recovery is discussed in connection with simple and operable recovery systems f or exhaust and cooling circuits. Maintenance standards as related to improved reliability and reduced fuel and operating costs are also outlined. IntroductionDiesel generators are used in Canadian mining operations to provide electrical power for "" base- load"" requirements in some instances and for ""stand-by"" or ""emergency"" power in almost every producing mine in the country . There are over 300 mines in Canada of which only a handful have to generate their own electricity. Only one or two mine s enjoy access to a hydroelectric site. Consequently, the diesel engine is the principal prime mover because of its high efficiency relative to other prime movers in the size range in question.The author has been associated with several “base-load” plants in addition to participation in numerous projects requiring emergency diesel generators. Records indicate that engine performance in term s of reliability and efficiency lags behind other industries where the diesel engine is used more extensively, such as the shipping industry which is able to make a more prudent selection of original equipment and enjoy easy access to highly skilled operating and maintenance personnel. It is hoped that the contents of this paper will be of value to Canadian operators of diesel generators, in the generation of prime power or applications for back-up power."

Jan 1, 1986

A knowledge of the mechanics of wave propagation through the earth is essential if reliable communication systems are to be designed for coal mine environments. To obtain a reliable basis from which accurate propagation predictions could be drawn, a series of theoretical studies have been prepared for the US Bureau of Mines by Mr. Ramsay Decker of Spectra Associates, Inc. through a subcontract with Collins Radio Group. These reports formulate the analytical techniques from which we may derive frequencies and antenna configurations that yield the optimum signal-to-noise ratios over the greatest distances in mine environments. The reports of sections 2 and 4 deal with analytical techniques for determining the signal-to- noise ratio within a mine environment for loop-to-loop and line source-to-loop antenna con- figurations. The analytical results of these reports were then implemented into computer programs to obtain predictions concerning through-the-earth signal propagation. These preliminary predictions are based on noise data compiled by Bensema, Maxwell and Stone, and WVU prior to the extensive research conducted by the National Bureau of Standards (NBS). These initial measurements indicated a 20- to 30-dB lower noise level than that measured recently by NBS. The recent NBS data is that used by Collins in the final predictions. The following outline indicates the order and subject matter treated in the subsequent sections: Section 2 - Signal-to-Noise Analysis for Loop-to-Loop Mine Communications Section 3 - The Horizontal Electric Dipole Section 4 - Signal-to-Noise Analysis for Down-Link Line Source Mine Communications Section 5 - LF Communication Section 6 - The Application of Recent NBS Noise Data to Mine Communications Section 7 - Analysis of Mine Communication Propagation Programs

Nov 15, 1974

By William A. Hustrulid

The subject of surface mine development is large. This section covers the fundamental concepts involved in both the open pit mining of thick or steeply dipping deposits as well as the strip mining of thin, shallow, and relatively flat-lying seams or beds. Design involves the marrying of geometries, ore and waste characteristics, equipment, and economics so that the desired result is achieved. Generally, there are many possible combinations from which to choose. For example, extraction over a short time period requires one strategy while quite another is applied for longer times. Variations in supply and demand require some flexibility of operation. Customer requirements impose certain constraints regarding the set of possible designs. Over recent years, planning and operating considerations for surface mining imposed by environmental requirements have increased markedly. There have, at the same time, been enormous advances made in the design aids available to the mine planner. Computer simulation of the various options, whether it be for mine design or equipment selection, provides detailed information for decision making in real time. A significant challenge to the engineer/planner is how to best use the aids avail-able. Because of the widespread use of commercially available and in-house computer software by industry, this section does not deal with the details of planning (for basic coverage of mine development, see Section 7). Rather, some of the basic concepts are stressed. The principles involved in equipment sizing and selection are discussed. A highly important but sometimes over-looked aspect of planning, haul road design, is also covered. For surface mining operations of the future, in-pit crushing and conveying will become even more important. Some of the considerations for application evaluation are included. The section concludes with some future concepts for surface mining.

Jan 1, 2008

By Robert A. Cummings

A rock mass classification system has been developed for recommending drift support requirements in block caving mines. This development follows a two-year program incorporating field observations of support practice and performance in rocks of different classes, at several U. S. block caving mines. Popular rock mass classification systems presently in use for tunneling were applied at the various field sites; and were evaluated for conformance with caving mine support requirements and for general utility to caving mine operations. The developed system (MBR System) accepts readily-obtainable engineering and geologic data to yield a rational estimate of support requirements. The background and development of the MBR system is described in this report (Volume I). The use of the system is given in the Manual, a separate volume (Volume II).

Jan 1, 1984

By A. I. A. Salama

In this paper, the problem of sedimentation and consolidation of poly-disperse suspensions is considered. The solid particles are assumed to be of different densities. If the sediment solids stresses are dropped out of the system equations and using the Richardson and Zaki hindered settling model, it has been found that in the limit, i.e., as time approaches infinity, the fluid is completely displaced to the top of the sediment zone. Furthermore, the species segregate completely with the heavier and coarser particles at the bottom of the sediment and the lighter and finer particles at the top of the sediment. Practical observations do not support these behaviors and physical-ly such behaviors do not exist; consequently, results of this kind in the literature are unrealistic. Here, a mathematical structure of the poly-disperse sedimentation and consolidation problem has been proposed. In this case the compaction zone species solids stresses are introduced in the momentum balance equations of the system. The species solid stresses in the sediment are constrained so that the system equations are consistent, i.e., sedimentation and consolidation of two or more identical species should behave as a mono-disperse system. Such a condition has not been recognized and imposed in some of the studies in the literature, which has led to unreliable results. Two practical forms of species stresses that satisfy the system consistency condition are here proposed. It should be noted that the study of sedimentation and consolidation of poly-disperse suspensions could result in more realistic suspension interfaces compared to mono-disperse suspensions, and could lead to more reliable engineering designs of tailings ponds. Predictions of sedimentation and consolidation in models of poly-disperse suspensions are demonstrated using published data.

Jan 1, 2014

By O. K. Olawale, G. O. Edaogbogun, B. N. Ben‑Festus, F. Ben, F. R. Amodu

The environmental and health implications of artisanal gold mining activities at mining sites across Nigeria have rekindled research interest. This study aimed to assess the scalability of naturally occurring radioactive materials in gold mining sites in Iperindo, Nigeria. Soil samples were collected from three different mining sites and control locations and analyzed for natural radionuclides, mainly 238U, 232Th, and 40K, using gamma spectrometry having a sodium iodide detector. The average activity concentration values of 61.55 ± 3.71, 72.65 ± 4.45, and 1134.99 ± 38.12 Bqkg− 1 obtained from within the mining sites for 238U, 232Th, and 40K, respectively, were above the world permissible values of 33.0 Bqkg− 1 for 238U, 45.0 Bqkg− 1 for 232Th, and 420.0 Bqkg− 1 for 40K. The average activity concentration values of 15.26 ± 3.19, 21.46 ± 4.27, 381.04 ± 23.36 Bqkg− 1 estimated for 238U, 232Th, and 40K, respectively, for the control location were, however, lower than the global permissible values. The study also evaluated other radiological parameters such as radium equivalent, dose rate, annual effective dose rate, internal and external hazard indices, and alpha and gamma indices. The obtained values were 252.83 Bqkg− 1, 119.98 nGyh− 1, 147.15 mSvy− 1, 0.85 Bqkg− 1, 0.68 Bqkg− 1, 0.31 Bqkg− 1, and 1.89 Bqkg− 1 respectively. Except for radium equivalent, external and internal hazard risks, and alpha index, which were significantly lower than the recommended threshold, all other radiological parameters were higher than the recommended global limits. Moderate data reproducibility and a p-value of 0.000574 further reinforced the robustness and reliability of the results obtained in this study.

Feb 22, 2024

By D Bruce

OZ Minerals’ Carrapateena mine is a Sublevel cave mine located in South Australia, approximately 160 km north of the regional centre of Port Augusta. Carrapateena commenced underground development in 2016, with production commencing in 2019 and ramping up to 4.25 Mtpa by December 2020. In pursuit of continual improvement, the Carrapateena mining team sought to identify how it could better interrogate its current productivity levels and its drivers (root causes). During this process the team were confronted by a disconcerting number of different opinions (which often conflicted) on our actual productivity performance which led to a need for review. Although reliable data and a well-designed time utilisation model (TUM) existed, it was still unclear what actions needed to be put in place to improve productivity. This was for the following reasons: • Data sources were disparate unless significant effort was applied to compile them. • Data sources were not available in a format that could be easily viewed or analysed. • General understanding of the data which was collected and how it could be used was poor. • Process of regularly analysing performance and forming tangible actions to improve was lacking rigour. A project was then started with the goal to fix the areas stated above. An initial requirements gathering exercise was undertaken to identify key data sources for site which returned a staggering 42 known systems which were then shortlisted to the key systems that contained operational data and could generate tangible improvements when analysed. This paper discusses the approach to selecting the OZ Minerals Insights Hub as the chosen platform, and the effort and collaboration between cross-functional departments that was involved in transforming the data so it could be displayed in a useful way. The data sources identified included a fleet management system, two planning databases, a control system historian, and a mobile fleet machine data system. New processes were also introduced to digitally capture daily commentary; this was achieved utilising SharePoint Forms. Data pipelines were then developed in the Insights Hub platform to automate the ingestion and transformation of the raw mining data into curated data models for end user consumption. Tableau dashboard packages have been created to support facilitation of short interval control, daily review meetings, and weekly review meetings as well as data analysis of key equipment and locations. These dashboards visualise the mining data models in a form that provides the user a clear picture of what has occurred, why it has occurred, and where to focus improvement efforts. This has resulted in a team which is more accountable, more equipped to assess the root cause of performance, and more regularly able to make data driven decisions. The next step? To build this out from Mine to Mill and create a data indexing tool which will drive self-service reporting, a data agnostic platform and predictive tools that help our people continue to be one step in front.

Mar 29, 2023

By COLIN A. LAWRENCE, Anthony Del Vescovo

All Rights Reserved. Printed in the United States of America. Information contained in this work has been obtained by SME, Inc. from sources believed to be reliable. However, neither SME nor its authors guarantee the accuracy or completeness of any information published herein, and neither SME nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information. This work is published with the understanding that SME and its authors are supplying information but are not attempting to render engineering or other professional services. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Any statement or views presented here are those of individual authors and are not necessarily those of the SME. The mention of trade names for commercial products does not imply the approval or endorsement of SME.

Dec 1, 2017

By O. Llewellyn Jack

From September 1978 to December 1983, ESD Corporation (formerly a Division of FMC Corporation) undertook the development and testing of a bidirectional auger under contract with the U.S. Department of Energy. Underground testing began in August 1981 at Peabody Coal Company's Marissa Mine near Marissa, Illinois. The auger was developed to increase mine production and coal recovery without increasing land subsidence. It bored 4-foot-diameter by 10-foot-deep holes into pillars on 7-foot centers (each hole recovering 5 tons). All operating during this test was performed by maintenance personnel with the goal of finding ways to increase the machine potential. The maximum excavation rate achieved was 1.4 tons per minute. It was concluded that the concept of drilling short holes to extract coal from underground pillars without surface subsidence was practicable with a wheel mounted auger, but that more power was desirable for this mine, and that the hydraulically driven augering system that provided experimental versatility was not sufficiently reliable for production use.

Jan 1, 1983

By Dongjie Zhang, Shuxin Liu, Jianduo Wang

Broken rock mass and unreasonable stope structure parameters can cause excessive ore loss and dilution in sublevel caving; this is the main problem faced by caving mining in recent years. This paper proposes a stope structure parameter optimization method suitable for steeply inclined medium-thick broken ore bodies and evaluates the reliability and effectiveness through case studies. To solve the problem of large ore loss and dilution in the high-end wall sublevel caving method of Xilinhot fluorite mine, it is necessary to select proper stope structure parameters. Based on the theory of random media, an end-wall ore drawing experiment was carried out, and the bulk flow parameters needed to optimization of stope structure parameters were determined. In the experiment, it was found the draw-out body of high-end wall ore drawing showed a fine top and a thick bottom; the granular media had good fluidity. The reasonable caving step is determined to be 1.2 m instead of the 1.6 m originally used. Through the optimization experiment of the mining route position along the vein, the study found that the best route position is different with the ore body inclination. When the inclination angle of the ore body was 90°, the reasonable route was located in the center of the ore body. When the inclination angle of the ore body was between 85° and 90°, the route moved from the center of the ore body to the footwall at a rate of 22.5%. When the inclination angle of the ore body was between 80° and 85°, the route moved to the footwall at a rate of 54.8%. When the inclination angle of the ore body is not greater than 80°, the route should be arranged on the boundary of the footwall. Field application results showed the dilution rate reduced by 7.66% and the recovery rate increased by 7.31%. Field test results verify the effectiveness and applicability of the optimized stope structure, which corroborates the effectiveness and applicability of the optimized stope structure.

Mar 10, 2022

By R Fanni, D Reid, M Kulessa

Recent updates to Australian industry guidelines emphasise the importance of the assessment of liquefaction potential of tailings. This includes assessment of the cyclic liquefaction potential, and the post-seismic strength of tailings expected to undergo strength loss from seismic loading. Despite this increase in focus, a relatively small number of Australian tailings appear to have been characterised through cyclic and post-cyclic testing. This paper presents the cyclic characterisation of four Australian tailings, consisting of iron ore, lateritic nickel, vanadium and bauxite residue. Material was obtained either from surficial tube sampling or through remoulding samples in the laboratory from slurries. Testing consisted of monotonic, cyclic and post-cyclic tests for each material. For three of the materials, laboratory-scale shear vane testing was also performed to provide a comparison to post-cyclic strengths from direct simple shear.The results indicated cyclic resistances consistent with the results of other tailings presented in the literature. The lateritic nickel tailings provided the greatest cyclic resistance of the four materials tested, followed by the vanadium tailings. This was somewhat consistent with expectations for material behaviour based on index properties. Post-cyclic strengths were seen to decrease as cyclic strains increased, consistent with typical observations in the literature. Following significant cyclic straining, in some instances the post-cyclic strengths approached those obtained through residual shear vane testing. This provides further insight into the strain-dependent nature of post-cyclic strengths for some materials. The implications of these observations on the post-seismic stability condition are discussed.CITATION:Reid, D, Fanni, R and Kulessa, M, 2015. Cyclic and post-cyclic behaviour of four Australian tailings, in Proceedings Tailings and Mine Waste Management for the 21st Century, pp 207–214 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By E. A. C. Chamberlain

New techniques for the continuous sampling and analysis of mine air are expected to replace traditional methods used for the early detection of spontaneous combustion. It has been established that the rate of evolution of carbon monoxide is the earliest indicator of incipient spontaneous combustion. Two methods of continuous monitoring of this gas are available and are now in use in the UK collieries. The first is the UNOR infra-red gas analyser, which is flameproof and may be used underground; the second is a system of tube bundles, which permits air to be drawn from any critical point in a colliery and analysed on the surface. Each system has its advantages and disadvantages but both provide the colliery manager with far more information on the condition of his pit than could previously be obtained by spot sampling and laboratory analysis. This paper describes the two systems presently in use and assesses likely future developments.

May 23, 1905

By Charles D. Litton

A new prototype ionization-attachment fire detector was developed by the Bureau of Mines for detecting combustion-generated submicrometer particulates. It is much more sensitive than the conventional ionization smoke detector, and it has the following added features: 1. A primary charging current of unipolar air ions is generated by a gold-coated, radioactive center electrode of a cylindrical diode. 2. Submicrometer particulates are flowed axially through the unipolar cloud where they acquire charge. The charged particles impinge upon a third electrode, located downstream, resulting in a current which is directly proportional to the particulate concentration. 3. Additional electrodes analyze the particulates in terms of their mobility and thus determine their size distribution. 4. A filter and cyclone assembly protect the ionization chamber against ambient dust. An analysis of conventional ionization smoke detector performance is also presented in terms of source strength, chamber geometry, and applied potential.

Jan 1, 1977

By Eduardo Lozano, Vilem Petr

The use of explosives bring countless benefits to our everyday lives in areas such as mining, oil and gas exploration, demolition or avalanche control. However, because of the potential destructive power of explosives, strict safety procedures must be an integral part of any explosives operation. The goal of this paper is to provide a solution against the hazards which unfortunately accompany the use of explosives. For this reason, a blast shield is specifically designed and tested for protecting personnel against these unpredictable effects. This document will develop a complete analysis answering the following questions: what are the potential hazards from an air blast; what are their effects; and how can we be protected against them. In order to answer these questions, theoretical, analytical, and numerical calculations are performed. Finally, a full blast shield prototype is tested under blasting conditions proving its effectiveness as a safety device while explosives are used.

Jan 1, 2015

By W. J. Roberds

A formal and explicit yet cost-effective approach is proposed to ensure that decisions made during mine development are optimum (with respect to their ultimate consequences) as well as defensible. This risk management approach is based on probabilistic risk assessment and established decision analysis techniques, and appropriately considers the relationships among various mine development decisions, tradeoffs among consequences, the uncertainty in predicting consequences, and the benefits of flexibility to respond to changed conditions.

Jan 1, 1992

By J. F. Burr, D. P. Snyder, G. W. Luxbacher

"The Mine Improvement and New Emergency Response Act (MINER Act) of 2006 (PL 109-236, 2006) established the Office of Mine Safety and Health, functioning as the Office of Mine Safety and Health Research (OMSHR) within the National Institute for Occupational Safety and Health (NIOSH) and provided authority for awarding contracts related to the development and implementation of new mine technology and equipment. The OMSHR external contracts program was formed in accordance with the MINER Act and has since issued more than 150 contracts focused on worker health and safety. Initial funding for this program was provided by the United States Congress through two emergency supplemental appropriations and was focused on emergency oxygen supply, communications and tracking, and refuge chambers (also referred to as refuge alternatives). Since the MINER Act, Congress has continued to fund the program through the annual NIOSH mining appropriation. The program was supplemented starting in 2009 with an academic capacity building program directed toward developing university tenure-track faculty and facilities and supporting graduate students in the area of mine ventilation. Ground control was added as an additional focus area in 2011. A short synopsis of each contract is published on the NIOSH Mining website (www.cdc.gov/niosh/ mining/researchprogram/contracts/index.html) and final reports are available in digital form on request. A summary of the progress OMSHR has made over the 10-year period since the Act was published previously (Snyder et al., 2016).External contracts are broadly classified by the following areas:• Communications and tracking.• Emergency response.o Self-escape and breathing air supply.o Refuge alternatives.o Escape and rescue.• Equipment safety.• Fires and explosions.• Ground control.• Mine environmental systems (mine ventilation and atmospheric monitoring).• Worker/workplace health and safety.Contracts are issued under a request for proposal (RFP), through a broad agency announcement (BAA) or under an interagency agreement (IAA). An RFP solicitation includes a specific problem description and a well-defined scope of work to guide the offeror in preparing a bid to conduct the research. Under the BAA several problem areas are described and the offeror develops the scope of work and deliverables for the proposed research. An IAA is very similar to an RFP except it is a contract between two federal government agencies."

Jan 10, 2018

The process of gold recovery by gravity concentration is incorporated in the metal recovery flowsheet at seven Newmont Mining Corporation owned mining operations in Australia, North America and Africa. In 2009 gold recovered by gravity processing was equivalent to nine percent of Newmont's total gold sales of 5.3 million ounces. This paper will discuss these applications in detail including a review of plant flowsheets and presentation of recent operating results. Operating performance will be discussed with reference to ore characterisation procedures, interpretation of results, design considerations and optimisation practices as they relate to the recovery of gold by gravity concentration.

Jan 1, 2011

By N. Campbell

"The fault under consideration follows a northerly trend past the west; side of the original settlement of Yell ow knife; which is situated 600 miles; north of Edmonton and 400 miles from the Northern Alberta Railway; terminus at Waterways; Alberta. The mining properties chiefly concerned; include the southern part of the Giant claims; on the east side of the fault; and the Con-Rycon-Demelt claims; on the west side 3 1/2 miles to the south.; Geological data were also obtained from the eastern part of the A.Y.E.; property; which lies south of the Giant claims; and from the Negus; Meg; Yellorex; and Kam properties; which are south and southeast of the ConRycon-; Demelt claims (see Frontispiece; also Fig. 5).Recognition of the major faults in the Yellowknife Bay area, including the West Bay fault, which appears to be the greatest, resulted from the work of A. W. Jolliffe (formerly of the Geological Survey of Canada) in 1935 and subsequent years. It has been stated with little exaggeration that these faults rank with the largest known steeply dipping dislocations of the earth's crust.In the winter of 1939, a mineralized shear zone named the 'Creek vein' was found on the Giant property. It was noted that the space relationship between this shear zone and a body of quartz-feldspar porphyry is roughly the same as that between the Con C-4 shear zone and a body of acid flows lying north of the Con property. Coupling this relationship with the assumption that the movement along the fault is dominantly horizontal, it was postulated that the Giant shear zone represented the faulted extension of the Con C-4 shear zone.As geological information became more extensive, certain weaknesses in this concept became apparent, and when spectacular orebodies were discovered on the Giant property in 1944 the question of possible faulted extensions became an important consideration. Consequently, in the spring of 1944, an extended investigation was undertaken, the results of which are embodied in this paper."

Jan 1, 1954

By T Medhurst

Recent developments in geophysical borehole log analysis using the Geophysical Strata Rating (GSR) are now routinely used in a number Australian coal mining operations. This allows development of 3D geotechnical strata characterisation models for a range of purposes. The availability of this data provides a means to identify relationships between ground conditions and ground behaviour. As a result, several new design methods have been developed to assist in the strata management process such as roof support, longwall shield design and shaft stability assessment. This paper outlines these methods and provides examples of their application. CITATION:Medhurst, T, 2018. Geotechnical strata characterisation using geophysics and its application for coal mine design, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 420–433 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By Donald L. Freed

Design, development, factory test, and in-mine evaluation plans are presented for an Automated Extraction System (AES) that has been designed to fill needs which are present in the Mining Industry. The philosophy of design and proposed operation of the machine, as well as the relationships between these factors, and final machine configuration are reviewed. The AES is designed to overcome production problems resulting from the regulation of roof control, clean-up, ventilation, dust suppression, and operator protection required by the Federal Coal Mine Health and Safety Act of 1969. The design permits more continuous operation and greatly improves operator safety. The machine is a full-face drum-type continuous miner which includes self-advancing, continuous temporary roof support. Onboard self-advancing face ventilation, dust suppression, and air scrubbing equipment are also included in the design. A further improvement over existing equipment is the incorporation of an automatic programmed cutting cycle control system. All mining functions including movements of the roof support system are handled by this automatic system.

Jan 1, 1977