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By Edmund Newton

The Haile mine has been the outstanding gold-mining operation and the largest single producer of gold in the Appalachian region. Gold was discovered at the Haile in 1827, previous to the present operation, production has been nearly $4,500,000 (gold at $20.67 per ounce.) from somewhat over a million tons of ore, with an average extraction of about 70 percent. The Haile property, now operated by Haile Gold Mines, Inc., is in the southern part of Lancaster County, South Carolina, 3-1/2 miles northeast of the town of Kershaw and 55 miles north of Columbia, the State capital. (See fig. 1.) The corporation has a lease and purchase contract on 1,805 acres, covering the present productive area. In addition, it holds lease contracts on 1,500 acres additional adjacent to this area.

Jan 1, 1940

By Wujian jun

In the process of wire rod production, the rolled wire products must be cooled from the red-hot state to the normal temperature state. How to cool the wire rod after rolling is one of the key links of product quality control in the whole wire rod production process. In this paper, combined with the closed-loop transformation project of controlled cooling temperature of Xuanhuan iron and steel group co., LTD., the closed-loop related controlled cooling equipment (including water cooler, valve table, etc.), nozzle layout and process layout of water tank, and closed-loop software control system of controlled cooling temperature of high-line are analyzed and designed. Closed-loop system design USES temperature of cooling water cooling and water cooling two temperature closed loop regulating circuit, through temperature feedback and feedforward to achieve the uniformity of temperature adjustment, in order to prevent occur due to temperature closed loop control function with the phenomenon of a steel before and after the temperature difference is bigger, system Settings have "absolute temperature regulation" and "relative temperature regulation" selection mode. The system has a self-learning mode, which can modify the temperature feed forward formula. In addition, this paper takes the hard wire 82B rod as the test object, and studies the process parameters and the comprehensive mechanical properties of the rod before and after the water cooling system reform. The research results show that the temperature closed loop system, can ensure the rolled piece temperature control precision of plus or minus 10℃, enhances the stability of wire rod cleaner performance. It can reduce water consumption by about 186m3/h and improve the utilization rate of cooling water.

Oct 1, 2019

By R. R. Hornor, Geo. M. Hunt

The purpose of this paper is to point out some of the benefits and economies to be derived by the better selection , preparation, storage , preservation and utilization of mine timber , and to give some specific information on certain wood preservatives and processes suitable for mine timber preservation . The paper is based largely upon data obtained by actual experimentation and service tests conducted by the U. S. Forest Products Laboratory , Madison, Wisconsin, on wood preservation , covering a period of many years , and upon a field survey during the past summer by one of the mining engineers of the U. S. Bureau of Mines of some of the principal mining districts of Michigan , South Dakota , Montana , and Idaho , in which he made a general ' study of mine timber in metal mines , particular attention "being given to timber decay ; the conditions under which it takes place most actively ; the measures , if any , that are being used to combat it; and, finally, the advantages that might be anticipated in the use of chemically treated timber to prevent decay and thus prolong its life .

Feb 1, 1922

By D Kent

The introduction of digital technologies into the underground mining industry, in both coal and hard rock mining, has enabled many high bandwidth applications to be adopted by mines.Digital networks based on 802.11 b/g/n open Wi-Fi standards allow for many applications to be run over a single communication backbone. One important application has been tracking personnel and equipment via RFID tags. This tracking application has in turn formed the basis of a Proximity Detection System (PDS) or Collision Avoidance Systems (CAS). The paper discusses the growth in digital technology as the communication backbone in underground mines which has allowed the ‘convergence of technologies’ that has been occurring in the general business world to be available to underground mine operators. Then the paper will focus on the use of the technology in the increasingly important are of risk control around mobile plant underground. The specific use of digital devices for proximity detection, in both hard rock and coal mines, to provide a system that can deliver an additional level of control to the risks associated with people-vehicle interactions underground is discussed. The initial implementation of PDS in the hard rock mining environment is based on two zones of detection, required for large and relatively high speed vehicles. Information will include:•the principles of the underlying technology,•installation learnings and effectiveness, and•change management methodology and issues.The most recent development to integrate Mine Site Technologies (MST) PDS with Frederick Mining Controls’ HazardAvert® System to extend the overall Proximity System’s functionality in hard rock mines and for use in coal mines is overviewed.

Mar 21, 2011

By R. Karl Zipf

This report presents nearly all structural data available from explosion tests of 20-psi mine ventilation seals and concrete-block ventilation stoppings that were conducted by the National Institute for Occupational Safety and Health during 1997?2008. Although the seals tested were designed to meet the former federal 20-psi pressure design standard, the structural information contained herein on these seal tests will facilitate the analysis and design of coal mine seals that meet the new explosion pressure design criteria of 50 and 120 psi as set forth in the Mine Safety and Health Administration (MSHA)?s final rule on ?Sealing of Abandoned Areas.? The seal testing data are organized into six broad categories of seal structures based on the materials used and the construction method for those 20-psi seals: 1. Concretelike materials with steel reinforcement and reinforcement bar anchorage to rock 2. Pumpable cementitious materials of varying compressive strengths with no steel reinforcement and no hitching 3. Articulated structures such as solid-concrete-block seals and ventilation stoppings made of solid and hollow-core concrete blocks 4. Polymer and aggregate materials without hitching 5. Wood-crib-block seals with or without hitching 6. Articulated structures such as lightweight blocks with or without hitching This summary contains data on 52 different structures in the above categories?44 seals and 8 ventilation stoppings. The structural data sets include the applied loading on the tested seal represented by a pressure-time curve and, when available, the measured seal response represented by a displacement-time curve. The structural data sets enable the calibration and verification of numerical models of seal behavior at the 20-psi level, which may then facilitate future structural analyses of seal designs for the new 50- and 120-psi explosion pressure design criteria.

Aug 1, 2008

By Felipe Darabas Rzatki

Polyether ether ketone (PEEK) is a high performance thermoplastic often selected for high temperature tribological applications under chemically aggressive environments. The present work evaluate the tribological behavior of a high performance PEEK composite under ambient and high temperature (30 and 80°C, respectively). The atmosphere was also varied (air or tetrafluorethane). An AMTI tribometer equipped with a hermetic chamber and a heating system was used to carry out sliding tests of PEEK cylinders on 304 stainless steel polished discs (Sq < 10 nm) with reciprocating movement and 175 N normal force. Surfaces roughness analyses were performed with a white light interferometer. As expected, there was a strong influence of temperature on the tribological behavior of the samples tested in ambient atmosphere (25% decrease in friction coefficient associated with a 100% increase in wear rate). On the other hand, samples tested in tetrafluorethane atmosphere showed no significant friction temperature dependence.

Jul 31, 2018

By Jerry M. Whiting

Greater awareness of the increasing need to develop supplementary energy sources is accelerating us towards many basic decisions regarding future utilization of mined energy materials -- uranium, coal, oil sands and oil shale. The latter material comprises a major potential source of oil which will require creation of unusually large and low-cost underground mining systems. In this paper, the author briefly outlines and analyzes several of the factors which continue to provide the somewhat unique character of oil shale nine planning and mine operation.

Jan 1, 1974

By Edward L. Burwell

The Bureau of Mines conducted laboratory experiments to determine the change during retorting in the apparent permeability and the degree of compaction of beds of broken oil shale. Grades of oil shale studied ranged from 20.6 to 46.7 gallons of oil per ton (gpt), and the simulated overburden pressures applied to the shale were from 300 to 900 psi. Linear regression analysis of the data produced equations describing the response of the oil shale. Oil shales of approximately 20 gpt experience only minor apparent permeability reductions under test conditions, but richer shales (30 to 50 gpt) lose essentially all permeability. The permeability reductions were accompanied by corresponding decreases in bed height that ranged up to 37 percent of the original bed height.

Jan 1, 1974

By L. R., McLeod

NO important changes in metallurgical practice are exhibited in the smelter that has been erected for treating the Morenci concentrate: the material is charged to reverberatory furnaces without roasting, and the matte subsequently blown in Peirce-Smith converters to separate the iron and sulphur from the copper. In fact the process is essentially the same, except for preliminary roasting of the concentrate, that was adopted in the new smelter that was built for the Arizona Copper Co. at Clifton, a few miles away, to treat Morenci concentrate just before the start of the first World War, and which went into service in October, 1913.

Jan 1, 1942

By F. W. Gray

Ideal utilization of the heat energy in coal should theoretically be secured by supplying each atom of combustible material present with the exact quantity of oxygen necessary for complete combination. An intimate and equal admixture of the fuel particles with air is therefore to be sought. Coal, or the combustible substances of which coal is composed, may be used in solid or liquid or gaseous form. The use of coal in small particles intimately mixed with air is, in effect, a specification of coal in pulverized or dust form. There has been much important development of this manner of using coal, which may be instanced as the outstanding advance in the use of coal as a solid. The completeness and efficiency of combustion in a properly designed dust-fired furnace permits the use of locally available coals of inferior quality, and enables them to be used commercially instead of imported coals of better quality. That is to say, some grades of coal of low calorific value, that are not economically useable in lump form on grates, are useable in pulverised form, because of the more complete combustion thereby obtained, and the consequent more efficient results. In the case of coals that are unsuitable for steam-raising in grate-fired furnaces, because of clinker troubles, (arising usually from a combination of high sulphur content and low-temperature fusibility of the ash content) use in pulverised form has obvious advantages, and in addition gives the benefit of any heat units that are contributed by free sulphur in the coal.

Jan 1, 1924

By Ashis Bhattacherjee, Bijay Mihir Kunar

A literature review on quantitative analysis of mine safety studies revealed that investigators use a wide range of statistical techniques for the analysis of mine injury data. Researchers have addressed the various issues of accident causation and prevention through analysis of mine injury data collected from mines. These studies are generally based on historical accident/injury data without considering the injured person/population at risk. In this paper, a public health approach, based on scientific methods of epidemiology, is presented to address mine safety issues. Epidemiology is the scientific study of disease and injury patterns among populations in time and space. Originally, epidemiology was concerned with epidemics of communicable diseases. Then it was extended to non-communicable diseases. Safety researchers found that epidemiologic methods are the best tools for injury research, because the occurrences of injury and the occurrences of disease are quite similar. As a result, some researchers started applying this concept to injury research. This paper presents some of the techniques used in epidemiologic studies and illustrates the application of a case-control study design to evaluate the role of some risk factors associated with injuries in underground coal mines. In this study, the injured persons were identified and, simultaneously, interviews were conducted to find the significant risk factors responsible for occupational injuries in coal mines.

Jan 1, 2011

By Reinhard Bott

The Companhia Mineira de Metais (Brazil) runs a Zn-recovery plant in Tres Marias, federal state Minas Gerais, Brazil. The Zn-production is about 65,000 t/a, This corresponds to a concentrate throughput of about 255,000 t/a with a Zncontent of about 29.5 % at an output of 85 %, The plant is run continuously 360 d/a and 24 h/d, respectively. From this it can be concluded that: Input: approx. 650 - 700 t/d ore-concentrate and approx. 29 t/h ore-concentrate, respectively.

Jan 1, 1990

By Rodney Hundermark

At Anglo American Platinum’s Polokwane Smelter, radar instruments are being used to provide continuous measurement of the concentrate feed level in the six-in-line electric furnace used for smelting of nickel-copper concentrates containing platinum group metals (PGMs). The radar instruments are installed directly on the furnace roof, and a mechanical system has been designed to protect them from radiation and elevated freeboard temperatures and pressures. Signal validation criteria have been implemented to ensure that proper level measurements are being used by the PLC system. The feedback from the radars has provided an improved understanding of the furnace behaviour with respect to concentrate feed level control, individual feeding events, global feed rates, feed distribution and bath disturbances. In combination with a dynamic mass balance for continuous calculation of liquid level in the furnace, the radar measurements have enabled more precise feedback control of the concentrate blacktop depth. In turn this has yielded improvements in furnace stability.

By H. J. Handewith

"After having performed qualitative and quantitative tests on nearly 550 rock specimens from tunnel projects throughout the world and comparing the results with actual boring in eight distinctly different rock types which varied in compressive strength from 12,000 to over 34,000 psi, it has been concluded that any rock -andesite, granite and even taconite -can be machine-bored. The question is -can it be bored economically? The intent of this paper is to delineate the investigative needs to accurately and reliably answer this question. A piece of NX core in the hand represents less than 50 per cent of the worthwhile geologic information that could have been obtained from a given core hole. A thorough site investigation by competent personnel can gene-rally foretell to what extent, if any, varying geologic conditions will hinder machine progress.A laboratory testing technique has been developed that has been correlated well (80 to 120 per cent) with actual boring results. This technique will be discussed in detail. Rock cutter life is a function of the penetration rate and the forces required to sustain that rate. Cutters are now, and will be for .some time to come, the single, most expensive consumable item involved in continuous tunneling in hard rock. It is by strict attention to predicting these rates and forces that tunneling costs can be optimized."

Jan 1, 1970

By P Hulteberg

In this article, an integrated catalytic reactor design approach to produce PEMFC-quality hydrogen is evaluated. The design is based on a high level of heat exchanging perfonned internally, highly active noble metal catalysts and a woven wire mesh catalyst support system. It consists of an integrated steam refonner and a catalytic burner section, a water gas shift section and a preferential carbon monoxide oxidation section. The reactor design is described and experiments perfonned to evaluate the two reactors built are reported. The two reactors have a maximum output of 3 Nm and 10 Nm3 hydrogen/h respectively. In the larger unit, a total of six fuels, three gaseous (methane, natural gas and liquid propane gas) and three liquid (naphtha, ethanol and methanol), were evaluated. The larger unit was also used to investigate how variations of parameters such as steam-to-carbon ratio in the steam reforming part of the system and the relation between oxygen and carbon monoxide in the preferential carbon monoxide oxidation affect the reactor perfonnance. The smaller unit was used, after implementing automatic control, to run a system life time test for 480 h. The refonner system perfonned according to specifications on almost every aspect.

Jan 1, 2005

By M. Ataei, F. Sereshki, R. N. Masir

Given the inherent risks and disruptions in underground coal mining operations, strengthening the resilience of critical infrastructure has become a vital priority. This paper aims to evaluate the resilience of the underground coal mining environment using historical data and expert judgment. The study serves as a framework for optimising the utilisation of critical infrastructure to minimise operational disturbances. To achieve this, a practical methodology has been developed, incorporating nearly two and a half years of collected operational data, a hierarchical structure, and a systematic approach. Furthermore, a case study is conducted to demonstrate the real-world applicability of the proposed method. Finally, the resilience index isintroduced as a straightforward summation of ranked impact factors, providing a clear metric for resilience assessment.

Dec 15, 2025

By Jerry Williams

GEORGE WEINMAN: At this time, our co-chair, Jamie Davis from Phelps Dodge, will come to the podium. JAMIE DAVIS: Our next speaker is Jerry Williams from Phelps Dodge, Morenci. Jerry is the maintenance planning supervisor and is in charge of preventative maintenance and maintenance scheduling. Jerry&apos;s group uses predictive tools to monitor and predict the equipment failure throughout the mine, from pumps to shovels to motors, you name it. The title of Jerry&apos;s talk is "If You&apos;re Not Using Predictive Tools, You&apos;re Behind the Curve." I’ll turn it over to Jerry.

Jan 1, 1998

By J. G. Cullain

In conjunction with the over-all goals of energy conservation at Inco Metals Company, a program of improvement in compressed air utilization was established. Air flows were monitored and compared to calculated requirements to establish efficiency by area. With the cooperation of area management, measures were implemented to reduce nonproductive usage. At the operation, annual savings in power consumption alone were 80,000 dollars. The program is being extended to other mine areas within the Division.

Jan 1, 1979

By Zhang Yongzhu

In hydrometallurgical processes of PGMs separation and refining, differences between 1-PGMs (Ru;Rh;Pd) and h-PGMs(Os;Ir;Pt) in thermodynamics and kinetics have been observed. The successful practice in the separation and refining of PGMs in China, is mainly based on the following two kinetically extraction sequences of: (1) for the extraction of PGMs complexes in different configurations with coordination mechanism (AuCI,) -> (MCl6)2-> (MCl4 )2-> (MCI6) 3- , and the substitution rate for h-PGMs complexes with higher effective nuclear charge Z&apos; is much more slow than that of I-PGMs. and (2) for the extraction of PGMs in different configurations with oxonium (or ion -exchange) mechanism (AuCl4)-> (MCl4)2--> (MCl6)2-> (MCl6)3- and the extraction of h-PGMs complexes with low surface charge density is more fast than that of I-PGMs complexes. In view of atomic structure theory, the similarity of atomic radii and chemical properties and difficult separation of PGMs resulted from the Lanthanide Contruction between 5th period (1-PGMs) and 6th period (h-PGMs). The differences between h-PGMs and 1-PGMs are due to the loss shielding of 4f subshells on 5d electrons for h-PGMs with higher nuclear number, which makes h-PGMs have a higher Z&apos; (effective nuclear charge) and strong attraction for outer space electrons. As a result, h-PGMs metals and complexes are thermodynamically more stable and kinetically more inert than the corresponding 1-PGMs. The differences between h-PGMs and 1 -PGMs in aspects of elements properties, complexes, hydration, substitution and redox reactions , are discussed.

Jan 1, 1993

By Charles W. Villiers

AS is well known, there are large and valuable deposits of coal in British Columbia, both on the mainland and on Vancouver island. These deposits are widely distributed over the Province. The chief sources of supply on the mainland are found in the Fernie and Princeton-Nicola districts and on Vancouver island in the Comox and Nanaimo districts. The coals range from a very high quality bituminous coal to lignite. On the Upper Skeena river there is said to be a very large deposit of anthracite or semi-anthracite, but this field has not been developed. Coal was first discovered in British Columbia on the north end of Vancouver island in the year 1835, but it was not until 1852 that coal mining was seriously undertaken by the Hudson&apos;s Bay Company at Nanaimo, where mining has been carried on continuously ever since that date. The production of coal in the Province continued to increase until the year 1910, when the annual output reached its peak at 3,100,000 tons and a total of 7,800 men were employed in the industry. Since 1910, the production has dropped steadily until, in 1934, only 1,347,000 tons of coal were produced and less than 3,000 men were employed. This continued decrease in production has in no way been caused by lack of coal reserves. It has been due entirely to curtailment of markets. I do not propose to discuss coal mining practice in British Columbia, where we have all sorts of mining conditions, including submarine mining. There is no lack of coal supplies for either industrial or domestic purposes, nor is there likely to be any shortage of coal in the Province for many generations. We have our mining troubles, which increase the cost of production, but there are no insuperable difficulties to prevent the extraction of a large and increasing supply of coal. Our main difficulty-in fact our only serious difficulty-is to find a market for our output, and we must consider means which can be evolved not only to conserve our existing markets but also to expand them, at any rate within the boundaries of Canada. I will therefore confine my remarks chiefly to the all-important factor of Markets for our coal.

Jan 1, 1936