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By H W. Wu, D Humphreys

The structure of a comprehensive research project into mine fires study applying the Ventgraph mine fire simulation software, preplanning of escape scenarios and general interaction with rescue responses is outlined. The project has Australian Coal Association Research Program (ACARP) funding and also relies on substantial mining company site support. This practical input from mine operators is essential and allows the approach to be introduced in the most creditable way. The effort is built around the introduction of fire simulation computer software to the Australian mining industry and the consequent modelling of fire scenarios in selected different mine layouts. Application of the simulation software package to the changing mine layouts requires experience to achieve realistic outcomes. Most Australian mines of size currently use a ventilation network simulation program. Under the project a small subroutine has been written to transfer the input data from the existing mine ventilation network simulation program to æVentgraphÆ. This has been tested successfully. To understand fire simulation behaviour on the mine ventilation system, it is necessary to understood the possible effects of mine fires on various mine ventilation systems correctly first. Case studies demonstrating the possible effects of fires on some typical Australian coal mine ventilation circuits have been examined. The situation in which there is some gas make at the face and effects with fire have also been developed to emphasise how unstable and dangerous situations may arise. The primary objective of the part of the study described in this paper is to use mine fire simulation software to gain better understanding of how spontaneous combustion initiated fires can interact with the complex ventilation behaviour underground during a substantial fire. It focuses on the simulation of spontaneous combustion sourced heatings that develop into open fires. Further, it examines ventilation behaviour effects of spontaneous combustion initiated pillar fires and examines the difficulties these can be present if a ventilation reversal occurs. It also briefly examines simulation of use of the inertisation to assist in mine recovery. Mine fires are recognised across the world as a major hazard issue. New approaches allowing improvement in understanding their consequences have been developed as an aid in handling this complex area.

Jan 1, 2005

As the theme of this conference is æRediscover OtagoÆ it would seem appropriate to revisit the era of the gold rushes and subsequent mining industry which rapidly advanced settlement and economic prosperity for Otago, and left permanent reminders in the form of historic mining sites, many of which are now encompassed within the Otago Goldfields Park. I have been invited to give a paper at this conference on the subject of æHistoric Goldfields of Central OtagoÆ. As well as having a working involvement with historic areas through my employment with the Department of Conservation, I have a personal interest in the early goldmining industry of Central Otago as my grandfather came out from Scotland in the 1890s to help construct gold dredges on the Molyneux. My grandfather made headlines in the local paper in 1920 when he believed he saw a New Zealand otter at Island Block near Beaumont - but that's another conservation trail that I will not pursue any further today! For this paper I intend to divide my time to cover the following topics. Firstly, I would like to sketch a mental picture of the characteristics that make up the Central Otago landscape, and the general perception that early miners must have had when viewing this foreign land. Then I would like to briefly discuss the changes and the consequences in the early gold rush to Central. Finally, I would like+ to discuss the establishment of the Otago Goldfields Park, which I will illustrate with several slides.

Jan 1, 1992

By L. B. Berger

From time to time the Bureau of Mines receives requests for information and advice regarding the safety of using internal-combustion engines operated on butane fuel as prime movers for haulage and other purposes in mining and tunneling. The purpose of this, circular is to discuss the properties of butane and to present data in regard to the possible use of this fuel in underground operations. Published information on the use of commercial butane as a fuel for internal-combustion engines indicates that, insofar as performance is concerned, butane may be utilized satisfactorily and efficiently for this purpose. However, the introduction of a volatile, inflammable material such as butane into confined spares such as mines or tunnels would create potential fire and explosion hazards that should be given due consideration by those concerned with the promotion of safe practices.

Jan 1, 1944

By C. J. H. Steenkamp

Theoretically, the main driver behind a mining operations? sourcing decision should differ from company to company, and within a company from project to project, but in reality it often relates to cost. Research confirms that there are a number of factors, including cost, to consider when choosing between in-house and outsourced mining. While the literature is rife with factors to consider, little information exists on how to apply these in practice and the relative importance of the different factors to be considered. A study was conducted to determine whether mining is truly a core competency for a mid-tier commodity specialist mining company. Furthermore, a decision-making framework for mining operations sourcing was developed, and the critical success factors that should be adhered to if outsourced mining is chosen were determined. The research showed that owner mining is not a core competency for the mining company investigated. A decision-making framework was developed using the order winner/order qualifier structure, which can be used to facilitate the mining sourcing decision. The most important tools at the disposal of a mine owner?s team to manage a contractor miner are the social and output control mechanisms, according to the critical success factors study.

Jan 1, 2014

By Lloyd M. English

During the past 30 years, the research arena has changed significantly in all fields, mining included. The relative representation of the topics of research, how the research is performed and who has performed the research have all changed. Although there are a lot of subjective ideas and anecdotal "analyses" concerning these changes, there has been no actual study of these trends to verify the facts. This study was divided into six five-¬year periods for the purposes of comparison. Some of the trends analyzed are co-authorship, research areas, research sponsors and cooperative efforts. In today's research arena, 30 years is a long time. Technology has advanced more rapidly than in any time previously and that pace continues to increase. There are more researchers, more tools for research and an increasing number of companies, agencies and institutions engaged in research. The pace of change and its impact is often discussed and debated at professional meetings and in institutions that engage in research. These conversations will often influence the research decisions of the participants in directions to take or subjects to pursue.

Jan 1, 1995

By B Hartmann

In 2003, Independence Group NL purchased the Long Shaft Nickel Mine complex (Long) in Kambalda, Western Australia. Lightning Nickel, the nickel operating arm of Independence Group, faced considerable challenges operating the mine, with the most significant challenge being able to prove that the remnant ore at Long and the associated orebodies could be mined safely and efficiently. Given the seismic history at Long, the magnitude of these challenges could not be underestimated. In an effort to achieve 100 per cent extraction of the flatter orebodies, traditional methods such as room and pillar were dismissed. A method consisting of transverse sills, butting into each other was proposed. To stop fill material from the first sill rilling into the adjoining sill, it was proposed to backfill the sills with pumped cement fill. The capital cost of the fill plant was estimated to be in excess of $1.5 million and the cost for cement alone was $1.0 million per annum. Shotcrete was already an extremely useful tool in dealing with the widely variable stress environment, but was to be used in an innovative manner that would enable the full extraction of a tabular section of the Victor South orebody. A layer of shotcrete, approximately 100 mm thick, was to be sprayed on the up dip wall of the initial development sill. The sill was to be backfilled with ænormalÆ development waste and ætoppedÆ with sand backfill. The next sill, ie slightly up dip and alongside, was to be mined along the shotcrete boundary wall. With respect to wall stability, the premise was that the shotcrete wall would stay in place and prevent the backfill (development waste and sand) from rilling into the adjoining development. It was also proposed that any breaches of the shotcrete wall would be repaired using shotcrete before substantial inflow of backfill into the ænewÆ development. This paper describes the development and implementation of this mining method, as well as some of the associated financial aspects.

Jan 1, 2008

By M. E. Bell

The term "operational research" was probably first used to describe work started under E. C. Williams, now Director, SHAPE Air Defense Technical Center, late in 1937 or 1938, at the Bawdsey Research Station of the British Air Ministry, a laboratory center concerned with the development of radar equipment. After the practicability of the early techniques had been demonstrated, a large (for those days) program of development and installation was authorized. It was very soon realized, both by the Royal Air Force and by the scientists that almost as important as the gear itself was the way in which it should be used. Accordingly, it was decided that some scientists should cooperate to study the way in which the equipment should be deployed and operated in conjunction with the Royal Air Force. To distinguish this work from the normal work of a research and development establishment, the term "operational research" was coined. It merely meant at this time that this particular section of scientists was to be concerned with the use of the gear rather than with its technical development and it seemed natural to those concerned to adopt the word "operations" which has a specific connotation in the armed forces.' This method was later extended to peacetime business enterprise, government operations and other human activities. Operations research appears to have penetrated the extractive industries more slowly and less completely than other industries, the military, or the government. This may be due (1) to a difference in the attitude of management towards operations research, or towards research of any kind, for that matter; (2) to unsuitability of the extractive industries for application of the operations research method; (3) to inaccessibility of the data; (4) or to a lack of trained personnel who are interested in applying operations research to the mineral industries.

Jan 8, 1963

By Richard P. Sheldon

In the last several decades, techniques of data collection have been rapidly evolving. Automated spectroscopic techniques in the chemical analysis of rocks for example have advanced to the point that we can analyze samples faster than we can grind them. Remote sensors of LANDSAT give us intensity measurements in four color bands of every acre of the U.S. every 19 days. Common depth point seismic instrumentation systems used at sea for surveying and networks of seismometers arrayed around the country for earthquake studies likewise are generating vast amounts of data. These along with many other earth science data generating systems have caused a veritable data explosion. How do we deal with these enormous amounts of geologic data presently being produced as well as those produced in the past, and to be produced in the future? There is an immediate need to acquire and utilize past and present basic data in order to address today's national earth science problems. Also data being collected and stored now must be compatible with future data in order for us to be able to undertake the wide spectrum of analysis that must be made in the future. This is a big order! In order to organize and to be able to analyze these data, the USGS has embarked on a wide ranging program of compatible data base construction and the development of computer technology, based on interactive computing, to facilitate resource assessments and analyses. These activities are analogous to two sides of a coin. One side deals with the logic, philosophy, and mechanics of information storage and retrieval; and the other side deals with the sensible application of computer technology to the treatment of data. These

Jan 1, 1977

Beyer Barometric Condenser The Ingersoll-Rand Co. is now offering to the trade complete steam­condensing plants for all service conditions. This equipment includes the Beyer barometric condenser, for' which the company has secured the patent rights, Imperial duplex and Ingersoll-Rogler straight-line reciprocating dry vacuum pumps and, where required, Cameron simplex and centrifugal pumps. The Beyer barometric condenser is of the counter-current type, in which air and cooling water flow in opposite directions. The steam inlet is at the bottom of the condensing v el, the water inlet above and the air-removal opening at the top. The sheets of cooling water over owing the pool at the inlet point meet the entering steam. The two are brought into intimate contact by conical baffle plates which assist the water to absorb to its full capacity the latent heat of the steam. The non-condensable air liberated in the condensing action rises through the falling water to the removal point at the top, being cooled to practically the temperature of the incoming water. It is also to be noted that ample opportunity is given for the removal of the air content of the water before

Jan 8, 1916

A process was developed, on a laboratory scale, for the removal of iron oxides from Weipa pisolitic bauxite. The technique involves the chemical reduction ofthe iron oxides by carbon, followed by selective removal of the iron species by acid leaching or chlorination.To remove more than 90 per cent of the iron it is necessary to reduce the iron oxides substantially to iron metal by heating the bauxite, pre-calcined at 650-800°C, with reactive carbon at 1040-1100°C. Reduction proceeds via the intermediate formation of hercynite (FeO.Al2O3) and difficulties have been encountered in reducing hercynite formed under less favourable reduction conditions.Following reduction, efficient selective removal of iron species is readily effected by acid leaching using dilute hydrochloric acid at 100°C, or chlorination at 500-750°C using Cl2, Cl2/N2, or Cl2/N2/CO mixtures.After removal of unreacted carbon, the final products contain 0·5-1.0 per cent Fe203 and 87-92 per cent Al203.

Jan 1, 1971

By V. A. Melezhik, A. H. Green, L. N. Grinenko

Finally, a theoretical model is constructed that takes

Aug 1, 1994

By John M. Devine

The severe corrosion of equipment that is caused by the presence of hydrogen sulphide in oil and gas has been described in detail by several authors.5 Such corrosion, termed "low-temperature hydrogen sulphide corrosion", presents a somewhat different problem from the "high-temperature hydrogen sulphide corrosion" that is encountered in refinery operation and

Jan 1, 1932

By Hubert E. Risser

Although, for about a half-century the percentage of coal production provided through strip mining has steadily increased, recent trends indicate that a peak in percentage (not tonnage) is being approached, principally because of the decline in economic adrantage enjoyed by strip mining compared to underground mining. Factors contributing to the decline are the decrease in the margin of advantage in manpower requirements held by strip mining; an increase in depth and volume of overhurden, requiring larger equipment and capital investment; increasing lack of reserve land blocks large enough to support extensive strip mining operations; more stringent legislation for reclamation of stripped land, with increasingly higher costs of such reclamation; and the increasing costs of land surface rights for strip mining. Already there has been a peak and suhsequent decline in relative importance of strip mining insome major Eastern coal-producing states; trends indicate that a peaking for the whole Eastern region is on the way. Although, in the West the pressures are less severe, they will, nevertheless, reduce to an increasing degree the advantage that strip mining has possessed. For about half a century, strip mining has been providing an ever-increasing share of total coal output in the United States, and in the past 30 years this share has grown from less than 8% to 33.7%, as shown in Fig. 1. Fig. 1 also shows that strip mining is gaining faster in the West than in the East. From 1961 to 1967, output from strip mines grew 63.6 million toqs, or 52.2%. Certainly there is nothing in such performance to indicate any peaking in the level of strip coal-mine production. But the fact is that, if not in actual tonnage, strip mining appears to be reaching its peak in relative importance, at least east of the Mississippi River. And the area east of the Mississippi provides 90.0% of the strip and 94.9% of the total coal production of the nation. The relative economic advantage which spurred strip mining's growth for a third of a century has been diminishing markedly in recent years. Fig. 2 shows evidence of this decline. From 1947 until 1961, strip tonnage output remained fairly stable, at the end of the period showing only a 12.5% decline. Meanwhile, underground coal production fell 44.5%. As the result of the greater decline in underground coal, strip coal in 1961 furnished 30.3% of the total coal produced, compared to only 22.1% in 1947. In the succeeding six years, however, underground coal output increased by 76.5 million tons, while strip output increased only 63.6 million. Further evidence of the strengthening of underground coal's relative position — or if you will, the weakening of strip coal's position — can be found in the major coal stripping states: Illinois, West Kentucky, Ohio, Pennsylvania, Indiana, and West Virginia, which in 1966 provided 80% of the nation's strip coal. Fig. 3 shows what has been happening in three states lying in the Appalachian field and in the total output of these three states. In the figure, the column height represents the output of coal mined by all methods. The number at the base of each column is the percentage mined by stripping. In Pennsylvania and Ohio, the percentage of strip mining increased between 1956 and 1961, but by 1966 had declined from the 1961 level. In West Virginia, a decline occurred during the first five years but was followed by a rise. In January 1968, Coal Age published an article listing the locations and capacities of new large mines in the planning and construction stages that would be operating by 1968-1971. The plans for West Virginia and Pennsylvania indicated all the new mines would be underground. Except to the extent they might replace existing under-

Jan 1, 1970

By Jerry C. Tien

Mining in China dates back at least 4,000 years. Today, with no less than 103,000 metal/nonmetal mines and between 40,000 to 80,000 coal mines, China’s mining industry is undoubtedly the largest in the world. Despite improvements in recent decades, seemingly endless mining accidents continue to make the news. Official coal mining deaths were 6,702 in 2003, and 6,027 miners died in 2004; actual figures may be much higher. Added to these were the 2,699 deaths in the metal and nonmetal industries. Most of these accidents were due to CH4 (methane gas) explosions and fires as a result of inadequate mine ventilation de-sign or practices. A good portion of these accidents occur in small, privately run and often technically illegal mines. During the past 10 years, the Chinese government has attempted to crack down on small and often technically illegal mines without much success. The number of accidents and associated fatalities has not significantly reduced. However, there appears to be a new urgency in China’s efforts to step up mine safety in the country. After its worst reported mine disaster in more than a half century, the government quickly paid reparations to families, suspended high-level officials in charge and announced additonal reforms. One of those was the elevation of the central government’s work safety office to cabinet-level status. There has been increased transparency in reporting and investigation of mine accidents and disasters in recent years. There has also been an increase in public criticism by labor leaders concerning the neglect of mine workersafety.1 This article examines the causes of China’s many mining accidents, current legal and enforcement structures, respective mining health and safety related laws and regulations, recent mining industry developments and the latest effort to curtail small mining operations.

Jan 1, 2005

By H. F. Yancey, E. Zane

"INTRODUCTION The term ""friability"" as applied to coal may be defined as the physical property of coal which expresses its tendency to become reduced in size during handling as a result of such external forces as impact and attrition. Thus friability is a quantitative concept and property, and hence can only be defined in relative terms or in terms of measurement. Methods of measurement are difficult to formulate and apply because coal is anything but homogeneous in physical structure and chemical constitution. aMoreover, friability itself is a composite property obviously dependent upon a group of other specific characteristics such as cleavage, fracture, tenacity, hardness, and elasticity, which vary from coal to coal with change in rank and even between individual coals of the same rank. These characteristics affect the friability values of different coals to varying degrees, but this fact does not impair the usefulness of and the need for friability measurements.The amount of breakage or degradation in size that a coal suffers in mining, preparation, and subsequent handling depends upon its inherent friability and the severity of the handling treatment which it receives from the time it is taken from the bed until it reaches the consumer. The value of the coal to the producer and jobber depends in large measure upon these same factors--friability and severity of treatment—because the larger sizes still command a premium in the ordinary market. Although much has been accomplished by the coal-producing industry in minimizing the breakage of coal in mining and preparation, it is apparent that additional reductions in breakage must await further improvements in design of coal-handling equipment. Such improvements will result from more intensive investigations of the extent of breakage or degradation in size occasioned by specific mining and handling operations and the development and application of standardized methods of evaluating friability.The work described in this report was undertaken to assist in the development of standard methods for evaluating the friability of coal. Specifically, the work deals with a Comparison of the various methods previously proposed for estimating the friability of coal and coal products. This same objective is now being sought at a number of other institutions, both in the United States and Canada, by a committee of the American Society for Testing Materials. It is believed that by providing additional information concerning a property of coal pertinent to its increased usefulness, the work described will supplement and increase the useful of the data which long have been, and still are being, furnished by the bureau of Mines on the composition of coals of the United States."

Jun 1, 1933

By R. L. Marek

The number of Persons fatally injured in the petroleum industry in California in 1930 was 50, a decrease of 20.6 per cent from 1929, when 63 men accidentally lost their lives. The decrease in the number of fatalities for 1930 has caused the first downward trend in the fatality curve of the California petroleum industry since 1927 and is coincident with a period of little active development in new fields, the shutting in of many wells, and reduced activity in the older fields of the State. That a direct relationship exists between the number of accidental deaths and the rapidity of new field development is particularly emphasized by the fact that in 1929, a year of intensive field development in California, 48 men were killed in the drilling and producing division, whereas in 1930, a year of less development work, only 25 men were killed in this division. The figures for the average number of drilling and producing wells in 1930 decreased appreciably from comparable figures for 1929 and a greater percentage of producing wells were shut-in in 1930 than in 1929.

Jan 1, 1931

By R. L. Marek

The number of persons fatally injured in the petroleum industry in California in 1930 was 50, a decrease of 20.6 per cent from 1929, when 63 men accidentally lost their lives. The decrease in the number of fatalities for 1930 has caused the first downward trend in the fatality curve of the California petroleum industry since 1927 and is coincident with a period of little active development in new fields, the shutting in of many wells, and reduced activity in the older fields of the State. That a direct relationship exists between the number of accidental deaths and the rapidity of new field development is particularly emphasized by the fact that in 1929, a year of intensive field development in California, 48 men were killed in the drilling and producing division, whereas in 1930, a year of less development work, only 25 men were killed in this division. The figures for the average number of drilling and producing wells in 1930 decreased appreciably from, comparable figures for 1929 and a greater percentage of producing wells were shut-in in 1930 than in 1929.

Jan 1, 1931

By Frank B. Fulkerson

This is the second of two interrelated studies of waterborne transportation. The first study discussed transportation of mineral commodities on the inland waterways of the South-Central States.2 Together, the two surveys describe and analyze the flow of foreign and inland waterborne commerce of the gulf coast. All the principal mineral-industry imports and exports of the gulf coast are mentioned in the report, including metals, nonmetals, and mineral fuel products, The gulf coast foreign trade in mineral industry products was determined to be composed of a small number of commodities.

Jan 1, 1971

By H. David Swain

On Bougainville Island in Papua New Guinea, Bougainville Copper Ltd. (BCL) has successfully applied electronic data processing (EDP) techniques to pit operations and mine planning. Though the EDP program is not complete, BCL has realized significant improvements in short and long range mine planning, and equipment and manpower utilization. About 80% of BCL's 4000 employees are Papua New Guinea nationals, and most have little education or training. The operational characteristics of the computer equipment, however, have been quickly adapted by users with low educational standards.

Jan 3, 1979

By K. Thirumalai

The feasibility of breaking hard rock by thermal weakening and subsequent mechanical impacting was tested, Field tests at a basalt quarry in Dresser, Wis., demonstrated that large hard-rock blocks (5 by 5 by 5 ft) could be effectively reduced in size by this method. A series of secondary breakage tests, using air-propane heating, resulted in an average heating cost of $0.36 per ton. This combination energy approach provides an alternate means of size reduction of large hard-rock boulders for quarry and for underground are chute and grizzly operations where mechanical methods, used alone, are ineffective.

Jan 1, 1975