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By S J. Schafrik, Z Agioutantis, E C. Jong, K Luxbacher

Real-time monitoring of mine operating parameters is available at most mines. However, access to these data for an individual operation is typically underutilised by mine managers and technical personnel. Such monitoring systems are typically designed to provide data streams and alarms to a responsible person, but they are not utilised to extract underlying trends or correlate different data groups. Furthermore, multiple monitoring systems are usually implemented at a given site without interconnection between vendors’ systems or connection to any central management, and mine personnel are only exposed to a minimal subset of such data. Thus, it is not easy to analyse and correlate individual data streams and generate information to enhance day-to-day operational decision-making and improve safety and efficiency.This paper addresses the primary challenges associated with centralising data management and effecting greater utilisation of the vast amount of collected data, while at the same time reducing the time and effort required to manage such large data sets. Furthermore, it presents the conceptual design of a database application that can organise, present and analyse data collected by multiple sensors in different environments. The database is designed to operate in a passive manner so that active mine data management systems are not impacted. An example is given where this database is used for managing atmospheric data collected at an underground coalmine operation in the US. These techniques have a universal application and can be incorporated in a wide range of mining and construction projects.CITATION:Agioutantis, Z, Schafrik, S J, Jong, E C, Luxbacher, K and Karmis, M, 2015. A platform for managing and analysing atmospheric data in underground coalmines, in Proceedings Third International Future Mining Conference, pp 3–10 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By S. Dixon

The Phelps Dodge - PD/PERI Heap2D Model is a phenomenological stockpile leaching model that has been used to investigate the best operating practices for leaching chalcocite. The model was used to investigate the interrelationships of raffinate application rate, aeration rate, raffinate iron grade, acid cures, lift height, crush size, bulk density, air injection spacing and raffinate drip emitter spacing.

Jan 1, 2006

By Jan Kvinge, Aina Opsal Bakke, Yanjun Li, Jan-Ove Løland, Svein Jørgensen

"Compound casting is a very attractive approach to reduce the weight of components for some specific applications while keep both the functional and the mechanical property requirements. In this work, Al-7Si-Mg alloy /copper compound castings were produced through a low pressure die casting process. To reduce the oxide present in the interface, flux coating of the copper pipes was tested. The interface layer formed between the two alloys was investigated using Optical Microscopy (OM), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). Vickers Micro-hardness was also measured across the interface. Results showed that the flux coating prevented the formation of the metallic bond between copper and aluminum. Instead, high concentrations of potassium, magnesium and fluoride, coinciding with formation of KMgF3 and MgF2, were detected in the interface. In the castings without surface treatment, a continuous metallurgical bond was achieved. In the bond layer, various Al-Cu intermetallic phases have been detected. In addition, formation of primary silicon particles in the reaction layer was observed in all castings. The mechanism for the formation of the intermetallic phases and the strength of the interface layer have been discussed.INTRODUCTION Recent development in the automotive industry has focused on producing lightweight components, which can reduce CO2 emission and increase the efficiency. Often, one material alone is not able to meet the requirements for a specific use. The need for lightweight bimetallic components has therefore increased. Aluminum-copper bimetallic components can be used in wires and bus bars where conductivity is an important factor (Lee, Bang, & Jung, 2005). Compared to Al-Cu alloys, Al-Cu bimetallic components can reduce both weight and cost without reducing electrical and thermal conductivity (Sheng, Yang, Xi, Lai, & Ye, 2011). A challenge is, however, that aluminum and copper have high affinity to each other, especially at elevated temperatures. This causes formation of brittle intermetallic phases with high electric resistance (Liu, Wang, Sui, Wang, & Wenjiang, 2016). In addition, both metals are subjected to oxide formation on the surface. Copper is especially exposed to oxidation at elevated temperatures (Pinnel, Tompkins, & Heath, 1979), while a thermodynamically stable oxide layer will spontaneously form on the aluminum surface (Papis, Loeffler, & Uggowitzer, 2009). Oxides are known to be passive substrates, which will reduce wettability and will thus prevent the formation of metallic bonding between aluminum and copper (Papis, Hallstedt, Löffler, & Uggowitzer, 2008)."

Jan 1, 2018

By David R. Ziegler

The concept and facts concerning "threshold blast damage" are not considered "general knowledge". Perhaps because of a lack of knowledge, understanding, and experience of blasting effects, property owners and lay-persons may attribute a wide range of common cosmetic conditions to "blasting damage".

Jan 1, 1997

By T. Lamond, J. O. Costello

Marble is a preferred surfacing material in up-scale buildings. Its use increased in the 1870's with rising national wealth and declined in the 1950's when synthetic materials for these applications were developed. Natural marble is now limited to high-end domestic and commercial structures. Cultured marble is a paste of white marble dust and polyester resin cured in molds yielding fixtures of specific finished dimensions. Dyes incorporated at different stages in the mixing cycle mimic shades and veining of natural marble. This paper discusses the filler requirements for cultured marble production and reviews new techniques to cut and finish natural marble.

Jan 1, 1999

Invensys’ recently introduced Field Device Manager for Foxboro I/A Series distributed control systems provides the industry’s first solution that takes advantage of both the latest Enhanced Electronic Device Description Language (Enhanced EDDL) and FDT technologies. This combination provides comprehensive lifecycle support to configure, calibrate, commission, diagnose and optimize the performance of any vendors’ foundation fieldbus device. The I/A Series Field Device Manager enables users to take advantage of any EDDL, Enhanced EDDL and/or FDT host deliverables supplied by the device vendor.

Jan 1, 2007

By G. T. Lineberry

Underground mine development begins with the positive investment decision to mine and ends with the inception of full-scale exploitation. It incorporates all activities, personnel, and equipment required for creation of underground access to a mineral deposit. Because of the depletion of near-surface mineral resources, the reduced mobility of large surface mining equipment, increasingly stringent environmental constraints, and the introduction of promising innovations to rock penetration and rock excavating equipment (e.g., continuous miners, rock borers), under-ground mining is projected to account for an increased share of worldwide mineral production in the foreseeable future. Without proper engineering during the mine development phase, failure of the underground mining project is axiomatic. A frustration attendant to coverage of the complex area of underground mine development lies not only with the need for treatment of the many disparate specialties within the area but even with the lack of systematization of these specialties in what is recognized as a vital precursor to successful mining. Section17 offers insights into (1) the basic principles of the planning and design process, including baseline assessment, reserve determination, premine planning, and subsystem design (Chapter17.1); (2) equipment selection and sizing, with emphasis on exca-

Jan 1, 2008

By Calvin J. Konya

Overloaded blastholes and insufficient stemming are major factors in flyrock accidents at surface metal and non-metal mines, Accurate measurement of blasthole depth, stemming height, and water depth would reduce the overload and the probability of blow-out, flyrock, excessive ground vibration, and airblast. Problems result because current measuring systems are inaccurate and often difficult to used A literature survey determined measurement techniques and blasting parameters prior to 1970. Similar data were gathered for current practices in 11 iron mines, 30 copper mines, and 92 quarries. Most operations used a cloth tape to measure borehole depth and stemming height; approximately 10% of the operations had dry blastholes. Alternate measurement techniques were evaluated and discussed. Candidate measuring techniques with best potential for improvement over the present weighted tape method are disposable tapes or string chains, automated readout tapes, modified sludge level indicators and acoustic resonance methods.

Jan 1, 1981

By W. W. Adams

[The sfxteeith e-mud ?7ntior_,il SnS~ty Cn~potitior,, cohduc ted by th Bureau of Mines, United Stntes'I3epnrtzel?t oL' the Interior, hstc fist been closed, and the resvlt s reveal tbt t!:e co~yafir,~ compzniqs had fewer accir'.ents in prnyort?lon to t2.o numbcr,of nkr-l:q?lr~1 1:9:='czd thm in my other ycryx in t3o r~cordc of the conlcst, Pheco zrzu-J. con:estn me thus aclr,i-cvir.c; Shc?r purpoao of ~romo tine w.fe ty in t5c nip-i~y induc tq*.]

Jan 1, 1941

According to the Balandin's (1) "multiplet theory of catalysis", adsorption can occur only if atoms of the reactant molecules are congruent with surface atoms of the catalyst. Such a condition calls for certain definite geometrical relationships between the reactant molecules and the atoms at the surface of the catalyst. If such a match or geometrical 'fit' is not provided, the surface reaction will not take place. An appropriate analogy to this may be the lock and key theory that enzymes should fit a substrate just as a key fits a lock. Similar geometrical considerations in adsorption studies were made in connection with the flotation of minerals. Gaudin(2) and Gaudin and Preller (3) proposed that if the dimensions of collector ions are in registry with the mineral lattice, an ordered layer of adsorbed species is formed. They explained that the structural fit is one reason for good flotation of galena with xanthate. In another study, Bachmann (4) attributed the selective flotation of KC1 from NaCl with amine to the fact that the lattice parameter of the amine collector is closer to that of KC1. Schubert(5) investigated the flotation of various nonmetallic minerals with amine and pyridine, and related the dimensions of the collector ions with the anion distances of the mineral surface. He concluded that good flotation is obtained when the tolerance is within 20%. The geometrical theory has also been used by Groszek (6) to explain the preferential adsorption of n-paraffin onto the basal plane of graphite. The geometrical theory has thus been found useful in explaining adsorptive properties of an adsorbate relative to the substrate structure. The purpose of the present work is to examine the possibilities of a geometrical fit between sodium dodecyl sulfate and Cu(OH)2 surface, and to construct a crystallographic model of the surface compound.

Jan 1, 1974

By Richard Newcomb, Michael Rieber, William A. Vogely

INTRODUCTION The solid fossil and nuclear fuels, but especially uranium, are given prominent, indeed leading, roles by energy experts in most long range estimates of world energy futures. Optimistic forecasts are inspired partly by the disproportionately large solid fuels resource base compared to present rates of consumption or to oil and gas resources, and partly by the vision of inexpensive high technology applications. Such a view overlooks the fact that while resource- use disparities and new technologies give allure to the promise of the solid fuels, they do not guarantee cheap solutions to the basic problems of solid fuel uses: viz., their relatively difficult conditions for efficient ignition and control, including the management of environmentally acceptable residuals disposal. Contrary to the varied versions of this optimistic hypothesis, this paper shows that a great many persistent economic and technical problems interfere with such a simple inference. These act as constraints which qualify or dispute much of the national energy policy based on existing modeling of solid fuel requirements and optimistic engineering evaluations. The assumptions and techniques of such exercises are sometimes at fault. As often as not, however, the distortions created in open market fuel com- petition due to misdirected national energy policies themselves are to blame for misdirected efforts. A number of interesting implications result. Among them are the distinct possibility that the low technology applications will dominate, so that more direct coal and less synfuel or nuclear use will occur; that, accordingly, exhaustion rates for uranium will be low, that the most extensive growth of solid fuel through 2000 will be in conventional pulverized coal cumbustors, and that the traded share of the world coal bum will be much larger than predicted. These trends will place much more pressure on oil and gas prices than forecast by most experts. On the way to these findings the paper demonstrates that solid fuel resource adequacy in situ, balanced against the projections of demands as capacity requirements, mean little as conventionally measured by years to exhaustion or potential supply schedules. Indeed, all stock concepts of demand requirements or of fuel re- sources must be tied to the paths of the unit costs and the deliverable prices of all substitute fuels and systems over time. This requires a dynamic analysis of supply and demand, integrated with geological and engineering constraints, to provide insights into the multiple modes of market and product substitution. Market forces rather than technical promise will determine the allocation of the solid fuels. Moreover, the equilibrium paths of individual fuel prices and market shares are not easily simulated by general or network models, and decision makers will continue to rely on the partial, local comparison of alternatives in their choices of fuel systems at any time. 'The economics of the solid fuels differs from that of other energy sources in important ways relating to their form in use, conversion efficiency, (dis)economies and externalities. Petroleum and gas are in a more convenient form for

Jan 1, 1985

Official Program

Jan 8, 1950

By H. E. Hilliard

A method was investigated for detecting and counting filamentous iron bacteria in open recirculating cooling systems. It is simple and fast and does not require trained microbiologists. Samples from 26 systems were examined. Cells were cultivated on commercially prepared ready-to-use media. Cultures grew well on this medium and were identified as filamentous iron bacteria by microscopic examination and by their ability to deposit iron using the prussian blue reaction.

Jan 1, 1976

By L. R. Burdick

This paper presents a review of published investigation dealing with the importance of sulfur compounds in the deterioration of materials or providing some basis for estimating the extent of loss shareable to such air pollution. Materials included are cement, stone, metals, paint, leather, paper, sand cloth. The investigations may be divided into two classes, one of the laboratory type in which the sulfur content and the humidity of the air were controlled and the other dealing with the exposure of materials to atmospheres not under control. The first type of work has shown that cement is subject to deterioration by the action of sulfur dioxide gas. The experiments with stone indicate that although limestone takes up sulfur dioxide, from the air, moist sulfur dioxide-air mixtures alone cannot be used for establishing- the comparative weathering- qualities of the different types of stone by accelerated test methods. Laboratory tests indicate that sulfur compounds in the air accelerate the corrosion of iron, steel, zinc, copper, and nickel at normal air temperatures and at certain relative humidities. It has also been indicated that certain types of paint are, affected by high sulfur dioxide concentrations, and that paper is attacked by sulfur dioxide in the atmosphere. The investigations of the second type show the amount or variation of corrosion in different localities and under different types of exposure. The investigations (10) (18)4/ during which sulfur determinations were made indicate that sulfur dioxide is a main controlling factor in the corrosion of iron and steel but according to Quick (18) may not be for some nonferrous metals. In general, the laboratory tests do not Jive definite data on the loss due to sulfur compounds at the concentrations normally found in the air. The data from atmospheric exposures are not complete from the standpoint of the exact effect of the sulfur compounds. Damage to materials so exposed is affected by factors such as other chemical contaminants, humidity, rainfall, solid deposits, and sunlight. A simple scheme has been devised in Great Britain which is considered to provide a measure of the attack of sulfur compound, on building materials (1). Small cylinders coated

Jan 1, 1939

By E. J. (Kirk) Conway

Thirty-five years ago underground coal mining equipment consisted of simple but rugged machines powered by electric motors and hydraulics. The machines were maintained by maintenance personnel armed with a basic knowledge of hydraulics, electricity, and mechanical design. Over the years the the machine has been transformed into powerful complex mining systems. The maintenance burden has also increased. During this period significant advances have been made in maintainability engineering and system design techniques. Many of these innovations and techniques are applicable to the design of underground mining equipment. The objectives of this project were to; (1) determine the extent to which maintainability design concepts and principles have been applied to the design of underground coal mining equipment, (2) try to assess the impact of equipment design for maintenance on productivity and safety, and (3) develop a maintainability design guideline to enhance the design of new or rebuilt equipment. An equipment design review was completed at ten operational coal mines. Interviews were also conducted with mine management, safety, and maintenance personnel to identify machine specific design advantages and problems. Visits were also made to six original equipment manufacturers to discuss the design of their equipment for maintenance. Volume I presents an overview of the protocol used and a summary of the findings. Volume II includes the maintainability design guide for underground mobile mining equipment.

Jan 1, 1989

By R. F. Valene

This paper is not available for inclusion in the Proceedings at the time of printing. but it will be included as an insert

Jan 1, 1984

By Susumu Tsubota

Three types of reference gold catalysts, i.e., 3wt%Au/TiO2 (Au-Ti: Type A), and 0.3wt%Au/Fe2O3 on alumina beads (AUS: Type B), and 5wt%Au/Fe2O3 (Au-Fe: Type C), were produced in a test plant scale by Sud-Chemie Catalysts Japan, INC. under the licensing of AIST. To evaluate the validity of the preparation methods and conditions used for the reference samples, elemental analyses by ICP, particle size measurements by TEM, and catalytic activity measurements for the oxidation of CO and H2 over these catalysts were made. Gold catalysts can be prepared in a large scale of ca 400g for the Au-Ti and Au-Fe catalysts, 5 kg for the AUS catalyst with good reproducibility. It was confirmed that they were available for useful as the reference gold catalysts of World Gold Council.

Oct 1, 2003

By K. Schonert

Jigging is a separtion process that has already been described by Agricola in 1556. Fine size material is normally treated in a hutch jigging process, in which the heavy particles are penetrating the jigging bed and are recovered in the hutch. In this process, a ragging consisting of the same or higher specific gravity particles is inserted upon the screen. The ragging is used mainly as a valve to maintain a constant upward flow of the water. Since the heavy particles should pass easily into the hutch, the ragging particles are up to ten times larger than the maximum feed size (1). In the fine size range - 1 mm the performance of jigs is mainly insufficient; some of the low density particles percolate the ragging while the hutch water flow prevents the fine heavy particles from entering the bed (2). By giving a thin layer of particles, which posesses a density sensitivity in case of certain adjustment of flow conditions, directly on the screen, the precision of separation can be increased. Stroke length and frequency have to be adjusted to give this filter layer a homogenous porosity between 60 and 70% during the pulsion phase, and the "en masse" lifting of the bed, as it is known in jigging of coarser material, has to be prevented (3). In this case, the jig cycle is only of minor influence.

Jan 1, 1987

By W. S. Landers

In contrast to the large fund of information available on the carbonizing properties of Eastern U.S. coals, the experimental data available for most Western U.S. and foreign coals are meager. To supply some self-consistent data, the Bureau of Mines conducted 220 low-temperature carbonization assay tests at 500° C. in a laboratory-scale carbonization apparatus. The results are included in this report. The U.S. coals tested are from Alaska, Arizona, Colorado, Illinois, Montana, New Mexico, North Dakota, Pennsylvania, Ohio, Texas, Utah, and Wyoming. Assays were also made on coals from Canada, Ecuador, France, Greece, India, Mexico, the Philippine Islands, Thailand, and Yugoslavia. In addition, one assay of pine sawdust and one assay of a peat from Ireland are reported. Prediction equations were developed relating the yield of products of carbonization obtained at 500° C. in the assay unit to the proximate and ultimate analyses of the coals. The equations for predicting the yields of tar plus light oil, char, and gas, and the heating value of the gas, are considered good, each equation having a multiple correlation coefficient of 0.90 or higher. The equation predicting volume of gas obtained upon carbonization is considered as fair, with a multiple correlation coefficient of 0.84. A reproducibility study of the assay made on 10 replicate samples of a subbituminous coal indicated that the standard deviation of the individual products was 0.31 percent or less.

Jan 1, 1961

By PHILIP A. ZANG

The rapidly increasing use of motor vehicles in the United States has introduced an entirely new problem in the proper ventilation oftunnels , subways , and other confined spaces through which such machines must pass . This problem was brought to the attention of the Bureau of Mines by the New York and New Jersey State Bridge and Tunnel Commissions with reference to the ventilation of the proposed vehicular tunnel under the Hudson River . This tunnel , consisting of twin tubes 29 feet in diameter and 8500 feet long between entrance and exit , presented an unprecedented problem in ventilation both on account of its length and on account of the traffic density , which is expected to reach a maximum of 1900 vehicles per hour . An exhaustive study by the tunnel engineers of all available data on the amount and composition of automobile exhaust gas disclosed very little information on the percentage of carbon monoxide in motor exhaust gas from the average run of automobiles and trucks under actual operating conditions on the road. It was well known that carburetor adjustment and other operating factors changed the percentage of the poisonous constituent , carbon monoxide , from practically 0 to 12 or 13 per cent ; but no safe estimate could be made of the most probable figure without further investigation .

Mar 1, 1921