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By L. M. Chan, D. R. Carlson, J. H. Johnson

"This paper presents an apparatus and procedures to implement a methodology for controlling ambient air quality in a confined working environment, such as an underground mine, an underground storage area, or a tunnel. The air quality control methodology is directed at limiting the quantities of exhaust pollutants emitted by diesel-powered vehicles into the confined space by identifying vehicles that are excessive polluters. The methodology is based on tailpipe and ambient air measurements in the confined space, and the ambient air threshold limit values (TLVs) for the various diesel exhaust pollutants. The methodology consists of two computational methods; a deterioration criteria computational method to identify excessive polluting vehicles, and an engine performance computational method to determine engine performance and to provide information needed to diagnose engine faults. The methodology is designed for implementation in conjunction with a preventive maintenance program.The first part of the paper describes the mine air and tailpipe emissions measurement apparatus and techniques used to obtain data. This is followed by sections discussing the deterioration criteria and the engine performance computational methods. A section discussing some common engine emissions-related faults is also presented lastly, a proposed procedure to implement the methodology including a possible hierarchical structure for mine personnel involved to implement the procedures is presented.INTRODUCTIONDiesel-powered mining vehicles are gaining Popularity in underground coal mines and are almost universally used in underground non-coal mines due to their mobility, flexibility, and higher productivity. However, noxious gases and particulate matter in diesel engine exhaust are a concern because of the potential for being harmful to the health of miners. Diesel exhaust pollutant concentrations out the tailpipe of a mine vehicle change with time due to engine wear, inadequate maintenance, improper adjustments and other factors. This deterioration in pollutant concentrations, if not properly controlled, may adversely affect the air quality in an underground mine. To provide assurance that a clean and healthful work environment are maintained, a program is needed to identify and repair diesel engines that contribute to poor air quality. Also, earlier detection of deteriorated engines will make preventive maintenance possible, thereby eliminating further deterioration and possibly complete breakdown. Preventive maintenance also increases engine life and equipment availability in production which in turn will result in decreased operating costs."

Nov 1, 1995

By Carle R. Hayward

(Wilkes-Barre Meeting, June, 1911.) THE growing importance of metallography has caused a corresponding interest in the improvement of apparatus for preparing specimens of metals and alloys for microscopic examination. The purpose of this paper is to describe an electric heating-furnace, a grinding-and-polishing machine, and a device for mounting specimens, which are used in the metallographical work at the Massachusetts Institute of Technology. These three pieces of apparatus were designed and made in the laboratory of the Institute, and. each possesses some original features which may be of interest. ELECTRIC HEATING-FURNACE., The accurate control of heat necessary for metallographic work is best obtained by the electric-resistance furnace. Unfortunately, however, even the platinum-wound furnaces deteriorate with use and ultimately burn out, while the cheaper resistance-materials are often short-lived. Since the resistance-coil must be replaced from time to time, it is of advantage to be able to make this change with as little trouble as possible, and this is an important feature in the furnace shown in Fig. 1. A is a cylindrical galvanized-iron can, with two handles, B. A porcelain tube, C, passes through the central hole in the cover of the can and rests upon the asbestos disk, D; the bottom of the tube is held in place by the asbestos ring, E. The space, F, around the tube is filled with powdered magnesia. G is an ordinary assay-crucible, with the cover inverted so as to present a smooth top for supporting a second porcelain tube, H. The latter is wound with ?Excello " resistance-tape, 0.014

Dec 1, 1911

By C. B. Manula, R. L. Sanford, R. A. Rivell

A - Contains the coordinate pair information for deriving the co¬efficients of the 3rd degree polynomial which approximates the loading station equation. C(N) - Coefficients for third degree approximating polynomial. I - General DO LOOP variable. K - Position in BRANCH of next character. L - Format specification in DEFINE FILE statement. X - Uniform displacement for random uniform number. Y - Load increment At. AO-A3 - Coefficients of approximating polynomial for loading station equation. GR - Grade direction, or grade resistance. IQ - Counts quadruples of distance grade speed and end of route for determining total distance. IT - Intersection counter in XXXDEF. Il - Station number trip is leaving. Jl - Station number for trip destination. J2-J8 - Motor assignments and functions for given trip. KK - Location of starting grade and distance in DISTGR KK - Position of decimal point in real number. KZ - DO LOOP variable for motor assignment check. LL - Location of ending grade and distance in DISTGR. Ll - Position in IECB of station satisfied. L3 - Next available position for IECB sort. MM - Flag for printing the failure of sanding to overcome slippage. NN - Trip destination in MOTSER RR - Rolling Resistance. XK - Station level or type.

Jan 1, 1974

By Craig Haase

A. Introduction

Jan 1, 2003

By Karl J. C. Harries

"The Table of Contents that follows is only an example and is the Table of Contents from an actual negotiated agreement. It is merely intended to show how an agreement might be set out and the nature of possible provisions. As a negotiated agreement the format was dictated by the negotiations. It is not offered as a precedent of what should be contained in a joint venture agreement (“JVA”), the “proper” sequence of Articles, or a complete listing of the contents of joint venture agreements generally. The set-up used for an agreement should be decided by the parties and be one they consider flows in a logical and workable sequence. This example sets out the “deal” first, followed by the provisions relating to how work is to be carried out and then by administrative provisions necessary to make the agreement work. If you are more comfortable with, say, having the Committee provisions at the beginning, by all means have it drafted that way -- you are going to have to live with the agreement and work under it.Notes:1. The Table of Contents provisions appear in bold print. The italicized sections are annotations, which have been provided in some cases where the heading may not clearly describe the contents. They are not intended to be comprehensive, but refer to some specific matters that are considered to be of interest or to need some clarification.2. The subject matter of many of the articles and paragraphs is discussed or commented upon in the text of the book. Some of section cross-references have been provided. Such references are only to sections where the topic is a principal subject and no attempt has been made to provide a comprehensive indexing.3. Although this particular agreement is a three-party agreement, *B* and *C*, the Owners, are required to act as a unit (see para. 1.09. – § 8.44.), making the agreement effectively a two-party agreement. The parties insisted upon having a decision-making Committee and structuring the agreement accordingly. As is explained in § 8.11., such an arrangement is not recommended and can result in problems.5. See also §§ 8.24., 8.41. and 14.13. for discussions on tables of contents, summaries, and headings."

Jan 1, 2003

By G. Grassmück

The question of whether the air curtain principle could be used under conditions prevailing in Canadian metal mines was investigated. A vertical, portable BERRY air curtain was tested, at first in a wind tunnel built at Ecole Polytechnique at full scale (8-by 8-ft cross section) to simulate a drift and its lateral connections, and then in the haulage ways of a metal mine under actual conditions. The results permit us to predict under what conditions this type of air curtain is capable of acting as an air stopping or flow regulator and how it could be further developed.

Jan 1, 1969

By R. Heikkilä

As a part of a large research and development program in Finland, a system calibration for an UAV measurement method having practical experiments in a Jorvas Railway Yard design and construction project. The Railway yard construction are was measured using an UAV measurement device by Smartplanes (Smartone) and using some reference points measured by a GNSS device. The measured data was cleaned, combined and adjusted through Least Squares Optimization using the software developed by a Finnish company Pieneering Oy. As references, two different laser scans as well as total station surveys were used. For applicability evaluation, the accuracy of measurement, the reliability of measurement, and the economy of measurement were used. Based on the comparisons, the achieved precision of the UAV measurement was high, instead the accuracy of measurement was not sufficient in this case. The principle of this photogrammetric measurement includes a lot of redundant observations making it possible to achieve a high level of reliability. The economy in this Railway Yard Design project was not able to achieve.

Aug 1, 2013

By A Jewbali, R Perry, R Inglis, L Allen

"The use of conditional simulation to characterise mine plan uncertainty is increasing for the assessment of risk in mining projects. While the development of grade uncertainty profiles is relatively straightforward and can be validated using standard geostatistical techniques, the addition of geological uncertainty to evaluate total risk remains problematic. Some of the problems associated with geological uncertainty methods include the clustering of data in favourable geologic units, difficulty in training image definition and the inability to address change of support issues for categorical variables. Despite these obstacles, the importance of geological uncertainty as a contributor to total uncertainty has prompted Newmont to explore and evaluate the use of various techniques (and combinations of techniques) on different deposit types.Two orogenic deposits of different geological complexity were selected for the study: Subika, a shear zone-hosted deposit, and Merian, a deposit containing gold mineralisation associated with quartz vein zones and stockwork within which are found higher-grade quartz breccia zones. Newmont trialled various categorical simulation approaches to determine the applicability of these methods for each deposit type and the effect of parameter choice on the width of the uncertainty interval. Some of the techniques that were trialled include multiple point statistics methods, sequential indicator simulation using local probabilities as well as variations of these methodologies.The goals of this study included: gaining an understanding of which techniques may work best in which deposit types gaining an understanding of the intricacies of each method gaining an understanding of the effect that each method has on total uncertainty analysis.This paper presents a comparison of the various techniques and makes recommendations for their use in uncertainty analysis.CITATION:Jewbali, A, Perry, R, Allen, L and Inglis, R, 2014. Applicability of categorical simulation methods for assessment of mine plan risk, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 85–98 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 24, 2014

By H. C. Harrell

The Tennessee Valley Authority began employing geophysical well logging for foundation investigations in October 1973. Since that time more than 3,000 holes have been evaluated for engineering purposes. The Tennessee Valley Authority has not actively used geo-physical well logging for exploration of construction materials, but we feel that much of the information derived from geophysical logs for foundation exploration is applicable to the construction materials industry. This paper will then discuss geophysical logging as applied to foundation engineering and, by implication, the feasibility of use in construction materials exploration. The use of geophysical logging and percussion drilling instead of coring has greatly expanded TVA's data acquisition capabilities and has also resulted in substantial savings in time and money. Economical boreholes are obtained through the use of large percussion track drills (Figure 1). This equipment is capable of drilling through the overburden, setting steel casing on the top of rock, and drilling the rock beneath the casing. Holes as deep as 400 feet (121.9 m) have been drilled by this method.

Jan 1, 1977

By F. J. A. van Ruitenbeek, M. Dalm

In the presented study test work was performed with near-infrared hyperspectral imagery (NIR-HI) on 36 ore samples from a South-American epithermal Au-Ag mine. The aim of the test work was to investigate if NIR-HI provides information about the alteration mineralogy of samples that can be used to predict their economic value. Mineral distribution maps were produced from the hyperspectral images by using correlation coefficients between the image pixels and a set of reference spectra. These maps showed that detection of mineralogy with NIR-HI can be used to distinguish; i) ore particles with low Au and Ag grades, ii) ore particles with high carbon contents, iii) ore particles with high sulphur contents.

Jan 1, 2015

By M-d-N. Gagnon, P. Okono, Y. Bergeron

In the mining industry, decisions regarding the type and number of comminution tests to be completed typically rely on geologists? observations and conclusions when studying drill cores. Given that these decisions are based on visual observations, they are essentially approximate and often inaccurate from a comminution viewpoint, causing a sizeable margin of error in estimating characterization test needs. Consequently, companies are often forced to perform more tests than necessary, requiring a significant quantity of material, and accruing significant costs. Recently, a new device, called the Hardness Index Tester (or HIT), was developed, offering users a low cost in-house mechanism for estimating the comminution parameter A*b and the Bond Ball Mill Work Index at any mine site, with potential applications on fragments up to 25 mm from drill core. In late 2016, Agnico Eagle Mines Limited initiated a trial to investigate if having an HIT device installed in a core repository would make it possible to identify the different rock properties more accurately and determine the number and type of comminution tests required. The application of the HIT was not to replace the standard comminution tests, but rather to generate a high number of comminution and geomechanical parameters for the rock mass. Ultimately, the objective would be to determine the uniformity of the rock mass and, therefore, easily distinguish any potentially problematic zones. With this method, the appropriate number of standard tests could be determined, making the HIT not only an excellent complement to the standard laboratory tests, but also an indispensable device for a geometallurgical characterization. This paper presents the results from the HIT trial using samples from the Odyssey Project, which is a Mine Canadian Malartic property.

Jan 1, 2017

By N. Nišić, A. Cvjetić, V. Jovanović, D. Knežević, D. Nišić

The risks associated with operating water reservoirs and tailings storage facilities (TSFs) are different because of their different purposes, methods of construction and operation, and characteristics of the materials impounded and their flow behaviour. Regardless of the differences, these two types of structures are often put in the same category when it comes to risk assessment and the application of relevant methodologies, which may result in unrealistic outcomes. In this paper we investigate whether it is possible to apply the risk ranking methodology designed for water reservoirs to TDFs and overview the key differences between these two types of structures. We also provide a comparative analysis of the results obtained by conducting a risk assessment of the operation of a TSF, applying the method recommended by the International Commission on Large Dams (ICOLD), and analyse the results using the failure mode and effects analysis (FMEA) technique. It is concluded that a more realistic evaluation of risk levels can be obtained by adopting a systematic approach to risk assessment in accordance with the traditional risk definition on which the FMEA technique is based.

Nov 30, 2022

By Xu Wang, Bang Chen, Xiujian Luo, Wei Tang, Xiao’ou Xia, Fangming Liu

"The inertia cone crusher has lots of advantages, such as big crushing ratio, fine particle size, material layer crushing, good passing tramp iron performance and stable technical index, realized open crushing circuit and simplified crushing flowsheet. The crusher was input to China’s Beijing General Research Institute of Mining and Metallurgy (BGRIMM) from Russia’s Mekhanobr-Tekhnika Research & Engineering Corporation at the beginning of the 1990s. This paper introduces that after years of absorption and innovation how Chinese researchers optimized and creatively designed about transmission mechanism, bracing structure, kinetic parameters, lubrication system, dust sealing system, damping system and hydraulic control system etc on the basis of keeping its advanced theory and unique structure, therefore the crusher’s stability was raised and the usage cost was reduced greatly. Accordingly the inertia cone crusher in China has been widely used in many fields, such as mineral resources and the recycling of metallurgical slag. The achievement in cooperation was fully affirmed by governments of Russia and China, and cooperation of science and technology in the mining and metallurgy industry between Russia and China is promoted greatly. INTRODUCTION From the early 1950s, the former Mekhanobr Institite(now Mechanobr-Tekhnika Research & Engineering Corporation) devoted itself to the research of inertial cone crusher and put it into industrial application in the late 1980s. Inertial cone crusher is like a maverick flower in the field of crusher. With its excellent performance and excellent application effect, it shocks the world and is destined to shine with a bright future. In the early 1990s, the chief leaders of the Beijing General Research Institute of Mining and Metallurgy (BGRIMM), Academician Sun Chuan-yao and Professor Zheng Baochen, captured the extraordinary performance and strong vitality of inertial cone crusher with keen eyes. So the two big institutes started the cooperation to introduce inertial cone crusher to China. Since then, Inertia cone crusher has been able to flourish in China and have achieved impressive results with two institutes’ continuous effort."

Jan 1, 2018

By Richard Campbell, MEHMET KIZIL, Ismet Canbulat, Serkan Saydam

The design and effectiveness of ground consolidation to regain stability of longwall faces vary widely and are often based predominantly on-site precedence or what were considered successful applications at other sites in similar situations. Little is known regarding product migration characteristics or change in rockmass conditions as a result of the application of consolidation chemicals. This paper presents the in-situ testing rationale designed and implemented recently across several longwall operations in the Bowen Basin, Queensland, Australia to provide quantitative measurement of the actual zone of influence of various resin injection products. Product migra- tion was physically measured by monitoring the change in rockmass temperature as a result of the exothermic chemical reaction of the various strata consolidation chemicals used. In conjunction with strata coring and Lugeon transmissivity testing pre- and post-injection to characterise the improvement in rockmass conditions due to consolidation product injection. The results of the testing programme, migration measurements, and rockmass assessment are presented, along with a discussion on how site- based Rock Mechanics Engineers can incorporate the data into the design of strata consolidation plans.

Jun 25, 2024

By Ivo Filipovic

The steel melting process in an Electric Arc Furnace is a complex set of tasks, coping with highly dangerous hazards as fire, explosions, uncontrolled reactions, hot metal projections and gas or dust emissions. Melt shops are dangerous working areas for operators, recording statistics with a high frequency of injuries. In the past years, without dedicated safety equipment, there wasn't a real attitude to the risk prevention. The paper describes the available technological packages to eliminate the manned activities on the melting floor, with the aim to prevent accidents and keep furnace operators safe. The technological packages suite extends the automatic control of the EAF melting process to all the operations from charging phase to tapping. Plus, the integration of the most frequent operations by automated specialized tools effectively minimizes power-off times, enhancing reliability and improving the transformation costs.

Aug 17, 2017

By Murray Wood, Michael Schaffer, Makat Katom

"An expert system applied to the control of mineral process unit operations is, by its nature, the site best operating practice, having been designed by the local experts in conjunction with consulting metallurgists. The “common sense” layer in a MET (MinnovEX Expert Technology) solution determines an appropriate action for the current operating conditions through a developed heuristic model of the process (expert system). The magnitude of the setpoint change that is made is proportional to the confidence that the system has in its interpretation of the current conditions (fuzzy logic). The solution is always striving to take the process to a constraint and thereby optimise the operation. An accepted limitation of the solution is that the only way the system can determine if a constraint has been reached is to exceed it and then withdraw – essentially “experimenting” with the process. By leveraging a model, which can accurately ""simulate"" the process, this restriction can be circumvented by pre-testing the set point change through a ""what if"" analysis and then modifying the solution as appropriate.At Ok Tedi, the introduction in 1999 of a MET expert system for SAG milling resulted in significant improvement in circuit throughput. Yet, with the additional inclusion of an accurate model of the process there was still more that could be achieved. Hence, in 2002 a MET Neural Network model was developed and deployed to enhance the existing expert system solution. The principal objective of this model was predicting the effect that changes in SAG tonnage and density would have on the power draw of the mill - essentially a power predictor. The results have seen a decrease in process variance with an associated increase in average circuit performance.This paper describes the methodology by which the Neural Network model was implemented, the considerations and limitations when applying this technology and ultimately the results that were achieved."

Jan 1, 2003

Choosing the right valve for corrosive, abrasive slurry applications requires exacting analysis and a comprehensive understanding of the complete slurry process. Within the realm of flow control in abrasive and corrosive slurry applications, there is no room for a one-size-fits-all approach. To ensure minimal maintenance, maximum uptime and the lowest overall cost of ownership, the slurry processing toolbox must contain countless alloy and elastomeric pairings ? each carefully targeted to the particular process medium and conditions. This materials selection process is best tackled by turning to expert slurry application engineers and valve product managers who work closely with customers to specify the optimal valve for the given parameters. ?When plant operators and design engineers apply conventional valves in abrasive applications or use metal seated valves or simply apply the wrong valve for a particular flow control situation, it typically leads to rapid valve failure, the potential for hazardous leakage, unexpected shutdowns and costly downtime,? said Cal Cobb, valve products manager for Weir Minerals North America, manufacturer of Isogate slurry valves for service in mining, minerals processing and metallurgical environments.

Jan 1, 2011

By B. W. Cavender

"World-class manufacturing" (WCM) techniques can be applied in milling operations to substantially improve productivity and reduce costs. Through the use of "just-in-time" and "total quality control" practices, WCM methods establish an environment for continual and rapid improvement in all aspects of production operations, with particular gains in product quality, costs, flexibility, employee involvement, and responsiveness to customers. This paper examines WCM techniques that can be utilized specifically in the mill, and their influence on plant configuration, organization, and scheduling practices; equipment selection and maintenance methods; training; the role of supporting staff; and methods of data collection and analysis.

Jan 1, 1993

By F. A. Molloy

As a result of feasibility studies made in 1975 a 3-0 seismic reflection survey was shot over part of the Veendam salt pillow during 1978-1979. The Zechstein salt pillow, located in the northeast of the Netherlands near the town of veendam, occurs at a depth of 1400 m and contains three carnallite rich horizons over an interval of 300 m below top salt. MgCl2 brines are produced from these layers as feedstock for a magnesia plant, which starts up in 1981. Prior to the acquisition of the seismic data four wells had been drilled. The thickness of the carnallitite layers encountered in these wells varied between 50 and 125 meters. In view of these variations it was necessary to obtain a reliable isopach of the different layers. The 3-0 seismic survey covered an area of ± 4x4 km with a sampling interval of 20 m in all directions. The data was recorded it an area array using a 120 channel instrument. Final presentation of the data was in the form of 3-0 migrated acoustic impedance cross sections. The quality and resolution of the seismic data allowed reliable structural and isopach mans to be made. It was shown that the carnallitite layers are continuous over the area surveyed, whilst local thickening is "fault" related. Having this information brine production locations could be choosen in the thicker parts, allowing maximisation of production potential whilst avoiding faults and fulfilling mining regulations. A subsequent benefit of this approach is the possibility of using the seismic data to predict ore grade. Using the available wells as calibration points the acoustic impedance response of the seismic at the well was matched to the ore grade found. From these points a synthetic section was made with varying ore grades. Pre¬liminary results are encouraging and the liability of this predictive tool will be evaluated in the light of future drilling.

Jan 1, 1981

By L. Barry Phelps

The application of an open-pit Materials Handling Simulator (OPMHS) to analyze mine planning and scheduling problems in large surface mines is discussed. The mine chosen for this application employed a large stripping dragline working in tandem with a shovel-truck haulback system for removing overburden. Large bottom-dump trucks were employed behind a coal loading shovel to transport the exposed coal out of the pit. Specifically, the current operations and the recommendations for short term and long term improvements were simulated on OPMHS. The effects of changing the operating parameters of the equipment on the total system were evaluated. Several alternatives were also studied for the best use of the existing equipment if the current operating parameters could not be improved upon. The results of the application are discussed.

Jan 1, 1978