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By E. Siami-Irdemoosa, S. R. Dindarloo

"Pareto analysis was used to investigate the failures database of a Hitachi EX1900 hydraulic shovel over one year of continuous operation. The hydraulic system and hydraulic links, hoses and piping were identified as the most critical system and subsystem, respectively. A three-parameter gamma distribution function was identified as the best fit for a probabilistic modeling of the time between failures (TBFs). This distribution was used in a Monte Carlo reliability analysis of the hydraulic system. Autoregressive integrated moving average (ARIMA), within the context of a time series analysis of the TBFs, was proposed as a viable alternative to the traditional technique of distribution fitting. The mean absolute percentage error (MAPE) metric was used to compare the two models. The MAPE value that resulted from the ARIMA was 66 percent smaller than that from the traditional technique in predicting the TBFs. Resumen ¦ Se usó análisis Pareto para investigar la base de datos de fallas de una pala hidráulica Hitachi EX1900 durante un periodo de un año de operación continua. Se identificó al sistema hidráulico y a los enlaces hidráulicos, mangueras y tuberías como el sistema y subsistema más importantes, respectivamente. Se identificó una función de distribución de tres parámetros gamma como el más apto para un modelado de probabilidades del tiempo transcurrido entre las fallas (Tabes por sus siglas en inglés). Esta distribución fue usada en un análisis de confiabilidad Monte Carlo para un sistema hidráulico. El promedio de movimiento integrado auto-regresivo (ARIMA por sus siglas en inglés), dentro del contexto de análisis de serie temporal de los TBFs, fue propuesto como una alternativa viable a la tradicional técnica de ajuste de distribución. Se usó el porcentaje de la media absoluta de error (MAPE) para comparar los dos modelos. El valor MAPE que resultó de la ARIMA fue 66 por ciento menor que el resultado obtenido con la técnica tradicional de predicción de TBFs."

Jan 1, 2015

By T. L. Myron

In recent years increasing attention has been given to improving both the chemical and physical properties of sinter. The first step toward this goal was the production of a self-fluxing-sinter. More recently, blast-furnace operators have found that significant improvements in blast-furnace performance can be achieved by improving and controlling the physical size of the sinter. The results of full-scale blast-furnace tests have shown that blast-furnace production can be improved by using a closely sized agglomerate. The improvements obtained by the use of pellets, a closely sized agglomerate, are well known. In contrast, blast furnaces charged with sinter having a wide size spectrum have generally not yielded results as satisfactory as those from furnaces 1) * charged with pellets. Beginning in 1958, Appleby-Frodingham charged plus 3/8-inch sinter to their blast furnaces. Further tests by other companies in Canada, 2) the United States, 3) and Australia showed that blast-furnace production could be improved by about one percent when the plus 3/8-inch material in the burden was increased by one percent. Because of the promising results obtained with screened sinter, an extensive test program was initiated to determine an effective means of producing sized sinter in U. S. Steel's sinter plants. This paper describes the work done by the Applied Research Laboratory in this program.

Jan 1, 1965

Giant gold deposits are considered products of crustal-scale systems. Reduced fluids stored in mid to lower crustal reservoirs were discharged into mid to upper crustal sites of deposition. Elements of the architecture include crustal-scale structures, reduced packages of rock and regional seals. Gas-rich aqueous fluids were common but non-aqueous fluids may have been significant in the deeper parts of the systems. Fluid fluxes in over pressured domains were maintained by porosity waves. Abnormal heat input from the mantle may not be required once the systems were perturbed. Fluid-mixing and hypogene enrichment were probably the most significant precipitation processes.

Jan 1, 1999

By Stephen L. Bolivar

The Prairie Creek intrusion, near Murfreesboro, Arkansas, is the site of the only commercial diamond mine in North America. Three major lithologies are associated with the intrusion, a hypabyssal peridotite, a volcanic breccia in .which the majority of diamonds occur, and associated tuff. Previous studies, including mining history, geological, geophysical, petrological and whole-rock and mineral chemistry are reviewed. The recent suggestion, by other workers, that this intrusion may be more correctly called a lamproite is examined and supported. This has serious implications for diamond exploration in Arkansas and elsewhere in the U.S.

Jan 1, 1984

By N. J. Themelis, W. H. Dresher

Research is probably the least understood and the most underrated or overrated, depending on the circumstances, function of the corporate enterprise. Some companies become engaged in research because they consider it to be vital to their very existence, others in order to develop new business, and some with no clearer objective than to keep up with the competition. Whole new industries have resulted from research activities, such as the Xerox copier, the transistor, the computer, and have affected considerably our way of life. Companies have prospered or perished by pursuing the successes or failures of their research organizations. However. despite the tremendous effect that research has had on our modern civilization and the billions which are spent on it annually, we have not as yet been able to develop many hard and fast rules as to how to conduct it effectively and to a successful end.1 This section discusses the role of research in the United States and in the mineral industry and describes a few of the criteria and guidelines which have been developed to assist in increasing the probability for success in industrial research. Broadly speaking, the purpose of industrial research is to make a significant contribution to the long-term viability and the profitability of the sponsoring company. The sum total of technological developments has been a principal factor in establishing the United States as a world leader and the controlling element in the nation's balance of trade with foreign powers. The international aspect of most mineral commodities is a significant factor in the business decision-making of most domestic mining companies and should be an important factor in the operation of research and development (R & D) programs in these companies. The National Science Board has reported that in recent yean other nations have been gaining on the United States over practically the entire range of science. 2,3 On the positive side, the NSB reported a strong position for the US in the results derived from its investment in R & D. If the United States is to maintain a favorable trade balance, it must create new know-how through technological innovation in order to create new industrial products, processes, and services for which there is a global demand. As expressed by Chauncey Starr, president of the Electric Power Research Institute, "Unlike resources found in nature, technology is a man-made resource whose abundance can be continuously increased, and whose importance in determining the world's future is also increasing."' In recent years, the greatly in- creased pressures for environmental quality and energy conservation have enhanced further the role of technical innovation in insuring the future survival of the domestic industry. Technology is the challenge of American industry, and it is a challenge which the mineral industry must also accept, for processed minerals are the very raw materials and energy on which all of industry is based, it is technology which makes a mineral deposit into an ore reserve. The Natural of Industrial R D Research is usually thought of as being either basic or applied. Basic or fundamental research is the quest for knowledge and need not have any practical objective. Applied research is the search for a solution to a particular problem and therefore has a specific objective beyond the acquisition of new knowledge. Development is the next stage to the applied research experimentation and it generally consists of larger-scale tests to establish the technical and economic feasibility of the new process or product and to provide design information for its industrial implementation. The terms research and development are usually interconnected for the good reason that in many cases it is difficult to define where one ends and the other begins. For instance, in many cases, thermodynamic, kinetic, corrosion, and other research studies, which are needed to provide design data for an industrial plant, may prod in parallel with the pilot plant activities preparatory for this plant in order to conserve time. Often the final stages of a development project may involve the trial production of a new product for markeing tests or the trial operation of a new process on a "semi-industrial" scale pilot plant. Such operations may be termed "demonstrations"; hence, more

Jan 1, 1985

By Kenneth A. Rogers, Richard F. Hill

Introduction A number of processes for deriving more convenient liquid and gaseous fuels from coal are commercially available or in final stages of development. Generally, synfuels from coal processes have efficiencies ranging from 50 to 70%. Considerable engineering design and development work are necessary to bring forth commercial plants using the various technologies-but technological breakthroughs are not expected or needed. Gasification While a variety of solids handling, gas contacting, and gas quality upgrading techniques may be employed in the various gasification processes, the primary goal is the same-to convert a sulfur-containing solid to an essentially sulfur-free gaseous product. The gaseous product may be a mixture of hydrogen and carbon monoxide with nitrogen. Definitions are not rigorous, but high-Btu gas is generally over 900 Btu/scf(33 534 kJ/m3) and low-Btu gas is generally below 350 Btu/scf(13 041 kJ/m3). Medium or intermediate gas falls between these values. High-Btu production is more difficult, as it requires additional upgrading of a low- or intermediate-Btu gas stream to produce a commercially acceptable product. The carbon/ hydrogen ratio is adjusted either by rejecting a portion of the carbon, increasing the hydrogen, or a combination of both. The chemical processing steps include production processing gas containing carbon oxides and hydrogen by the reaction of carbon and steam (gasification); reaction of hydrogen and coal to form methane (a hydrogasification process); reaction of hydrogen and carbon monoxide to produce methane (methanation); and the removal of impurities. The gasification processes share a number of common techniques. The coal received at the plant site must be further cleaned and crushed or ground before it can enter the gasifier. Conventional cleaning methods are used to remove extraneous materials such as metal, rocks, etc. For some processes the coal must be finely ground so it may be fluidized or entrained in a flowing gas stream. For other processes crushing and sizing only are required. Agglomerating coals may be pretreated by heating, mild oxidation with air, or other procedures to assure smooth gasifier operation and to avoid reactor plugging. Nonagglomerating coals Such as lignite and subbituminous coal normally do not require pretreatment. Feeding a solid material such as coal to a higher pressure reactor is a difficult task. Dry feeders using a series of pressurized lock hoppers, or wet systems in which a slurry is pumped into the reactor, are used. The gasification step is the heart of the process. Here, the solid feed material is contacted with synthesis gas (carbon monoxide and hydrogen). The coal is devolatilized and a portion of the fixed carbon converted to methane. The gas-solids contacting methods used include fixed beds, fluidized beds, moving beds, entrained beds, and free-fall systems. The gasification process, overall, is endothermic and the heat required to maintain reaction rates is usually supplied by burning a portion of the coal feed. External heat sources such as electric resistance heating, molten salt or solid heat carriers, and the introduction of a hot hydrogen stream also have been tested. Following the gasification step the particulate materials and heavy hydrocarbons contained in the reactor effluent are removed by a water quench and solids separation system. If low-Btu gas or synthesis gas is the desired product, the raw gas is scrubbed to remove carbon dioxide and sulfur compounds and then is used directly. However, if high-Btu gas is desired, methanation is necessary. In most gasification processes, the hydrogen content of the gasifier

Jan 2, 1980

By C. RAMADINI, F. NURJAMAN, A. SHOFI, B. SUHARNO

Nickel demand is increasing along with the rising need for stainless steel and other alloy steel/iron. The small addition of nickel in such materials can improve impact strength, ductility and corrosion resistance. Nickel is generally obtained from nickel sulfide ores (nickel associated with sulfur) and nickel laterite ores (nickel associated with iron and magnesium silicate). Almost 60 percent of nickel is now produced from sulfide ores, despite its existence in sulfide ores being less than in laterite ores. However, the depletion of sulfide ore reserves makes the mastery of nickel laterite ore processing of important and immediate concern. Selective reduction followed by magnetic separation has been in development in lateritic nickel ore processing to overcome the issues of high energy consumption and pollution associated with conventional pyrometallurgy methods such as blast furnace and rotary kiln electric arc furnace (RKEF).

By R. E. Muller, L. G. Martin, J. M. Stonehouse

Erratic distribution of values in free gold ore bodies presents severe problems in sorting material in large scale open pit mining. However, an intense program of modern blasting techniques and less than modern gold panning results in good sorting at Houston International's Manhattan mine. Blasting technique is important. If the sample location cannot be relocated because of blasted material movement, information acquired while drilling is useless. So short benches are critical to minimize dilution. Though not very accurate, panning allows for rapid analysis. The more accurate fire assay does not provide the needed speed. Panning can be fairly accurate and errors made are mostly on the low side. Samples of mixed and broken stockpile material are used as checks on pit procedure and to develop stockpile content in¬formation. Added tonnages discovered offset the higher labor costs of this careful sorting technique. The mine is located in central Nevada's Toquima Range in the small mining town of Manhattan, 322 km north of Las Vegas. The mine has four epithermal stockwork ore bodies that are mined in two pits. The mine problem was that conventional ore control was not separating ore from waste. Assays of 6-m blast-holes were used on 5-m centers. The blastholes were relocated by stadia survey after blasting. Holes assaying above the cutoff grade were flagged and mined as ore. This system is practical and useful in high concentration ore bodies or in evenly disseminated mineralization. But it was not practical at Manhattan because of large gold particles and small ore pocket sizes. Ore pockets were often missed when drilling a grid area for blasting. Also, large gold nuggets made assay results unreliable. The probability of a nugget being contained in an assay charge is small. So most results were low, compared to actual grades mined based on stockpile samples. When a nugget found its way into a fire assay charge, the result would be far higher than the actual grade of material represented. In addition, disturbance by blasting created problems in relocating ore. Because of these problems, the grade control program was intensified in September 1979. It successfully separated ore and waste in blocked out ore areas and located more ore in "waste" areas. Known reserves mined to date have increased up to 50% on some benches. The methods used are modern blasting techniques, detailed assaying, and traditional panning of samples collected from active mining faces. These methods allow mining flexibility, to match the variable mineral occurrence in ore bodies. The united effort of the geology and engineering departments has been important to the program's success.

Jan 12, 1980

By Justin Jensen, Luis Moya, Jose Carlos Durazo, William Szolga, Tyler McCallum, Tim Doubleday

Sulfuric acid mist is an undesired by-product of the copper electrowinning process, caused by oxygen evolution at the anode which entrains droplets of the acidic copper electrolyte solution. As the oxygen moves to the surface of the cell, these droplets become aerosolized resulting in acid mist. The addition of chemical anti-misting agents to the copper electrolyte is a common mitigation technique. This paper details Syensqo’s laboratory development of a new environmentally friendly acid mist suppressant, ACORGA® EW98. The product exhibits excellent acid mist suppression and it is fully compatible with the adjacent solvent extraction process. Lab and pilot test results are reviewed ahead of future planned industrial trial testing.

Feb 1, 2025

By Robert W. Curtis

Kaiser Aluminum & Chemical Corporation's (KACC) entrance into the alumina market began in 1946 with the purchase of a small plant in Baton Rouge. Louisiana. Since that time KACC has been involved with the design, construct; on, and operation of many alumina plants around the world. One of these plants is located in Gramercy, Louisiana. The Gramercy Works is a multiplant installation consisting of an alumina plant, a caustic-chlorine plant, a petroleum coke calciner and a fluorochemicals plant. Each of these plants require their own specific environmental control programs to abate pollution. Kaiser has made significant progress through the years on their own initiative in pollution control. But many new challenges have been and continue to be created with the enactment of environmental laws. The 1970 Clean Air Act Amendments, the resurrection of the old "Refuse Act" in 1970 and finally the 1972 Federal Water Pollution Control Act Amendments prompted the formulation of our current philosophy towards the abatement of pollution. Since the formulation of these complicated pieces of legislation, others equally complicated, have come to being. The Federal Insecticide, Fungicide and Rodenticide Act as amended by the Federal Environmental Pesticide Control Act of October, 1972, the Toxic Substances Control Act of 1976, the Solid Waste Disposal and Resource Recovery Act of 1976 and the Safe Drinking Water Act sighed in December of 1974 have all contributed to the challenge for an alumina plant to meet regulatory constraints. However, this paper will only discuss the alumina plant?s environmental programs designed to meet compliance with air and water pollution legislation. At the Gramercy Alumina Plant, over $25 million has been spent for pollution control since 1969. The Gramercy Plant is a prime example of KACC's commitment to meeting the environmental challenge.

Jan 1, 1978

By B. A. Massey

Sooner or later, we'll encounter a subordinate, peer, or boss that will test our management skills to the limit. The chances are good that our formal educations have not fully prepared us to effectively handle the situation, and through trial-by-fire, we have learned that the management of people is often as much an art as it is a science. Assertiveness - as opposed to agressiveness - is basically positive persuation. Assertive management techniques can help combine the art and science of managment to sell ideas, accomplish goals, direct the workforce, and generally promote the corporate - as well as our own - objectives

Jan 1, 1986

By G. Wayne Clough

During shallow tunneling in an urban environment, deposits or pockets of saturated soil or fractured, weathered rock are often encountered. Under such conditions, special problems with tunnel support, underpinning of structures adjacent to the tunneling, and/or flow of groundwater into the tunnel occur. If the ground conditions are appropriate, i.e., the soil is sandy, silty or fissured, or the rock is weathered or fractured, the solution to these tunneling problems may be chemical stabilization of the ground. Injection stabilization as an aid to tunneling is practiced extensively in Europe and its use is increasing in the U.S. The advantages of this technique over conventional solutions can be substantial in terms of cost and time, especially in mechanized tunnel boring where even a small zone of soft ground can bring the tunneling to a complete halt. In this paper European practice in using chemical ground stabilization for urban tunneling will be reviewed. In contrast to previous papers which have dealt with specific applications (1,5,8,9) this paper will broadly cover the subject, addressing itself to grouting techniques, costs, the reasons for grouting, philosophy of the users towards grouting, design of grouting solutions (or lack thereof) and methods of quality control. Differences with U.S. grouting practice are also noted. The information presented is derived from several visits to Europe, discussions with European and U.S. grouting personnel, and the available literature (2). The author's most recent European trip was made under the auspices of the U.S. Department of Transportation in conjunction with a research study being performed at Stanford University; a detailed report of this visit is available in reference (6).

Jan 1, 1976

By Jon C. Yingling

Lean manufacturing, pioneered by Toyota, has been credited with the most significant improvements in production efficiency and product quality since the transformation from craft manufacturing to mass production in the early 20th century. It represents a comprehensive philosophy for structuring, operation, control, and management of production systems that is believed to have wide applicability. This paper outlines major lean manufacturing principles and discusses their potential for application in the mining industry.

Jan 1, 1999

By Carlton H. Baab

In June, 1981 the Electric Power Research Institute (EPRI) issued a report titled "Control Systems in Coal Preparation Plants" to determine the status of instrumentation and automation systems in the coal preparation industry. EPRI concluded that the control systems presently being employed in the U.S. coal preparation plants "are relatively primitive compared with those in other mineral processing industries; and analytical instrumentation is virtually non-existent". Until recently, clean coal has had a low selling price and satisfying the purchasers' specifications required only minimum cleaning. However, it is becoming more apparent that the increases in coalfired utility power plants forced outage rates are relative to the deterioration in the quality of fired coal. Utility companies are becoming aware of the economic value of reducing the variability of ash, moisture and sulfur in steam coal purchase orders. New contracts are currently being negotiated between electric utilities and coal producers that include provisions for increased penalties if the product does not meet specifications. With tighter specifications on the quality of steam coal, interest is increasing in more sophisticated control systems. One type of device that is currently assisting the preparation plant operator optimize and control the coal cleaning process is nuclear based instrumentation. Nuclear instrumentation includes methods for measuring weight, level, and density as well as for performing elemental analysis on coal. This paper discusses the various types and applications of nuclear instrumentation currently in use in the coal preparation industry.

Jan 1, 1983

By Bernhard C. Koch, Richard W. Hutchinson, Bernhard Free

The Tertiary Silverton caldera collapsed asymmetrically to the southwest 27.5 m.y. ago. Resurgent volcanic activity is expressed by a quartz-monzonite stock at the southern caldera margin and by the Red Mountain porphyry stock in the northwest of the caldera which were emplaced at 25 m.y. and 11 m.y. b.p., respectively. The apical Eureka graben formed between 27.5-22.5 m.y. ago and transects the Silverton caldera southwestward. In the northeast it terminates at the 22.5 m.y. Lake City caldera margin. This graben as well as caldera faults provide dominant structural control for base and precious metal deposits. The epithermal gold mineralization of the Gold King mine is proximal to the Red Mountain stock in the north central part of the caldera. Here, west-northwest striking faults related to the collapse of the caldera intersect northeast faults of the Eureka graben. Superimposed upon earlier base metal mineralization at 23 to 22.5 m.y. b.p., the 11 m.y. younger gold metallization was a distinct event at Gold King. Supergene enrichment of the hypogene precious metal assemblage resulted in a metal tenor of up to 3,016 g/t gold and 1,088 g/t silver. The deposit is hosted by quartz-latite tuffs, flows, and flow breccias of the Burns Formation. Veins, up to 5 m wide follow steeply southeast and northwest dipping structures of the Eureka graben. Subsidiary veins up to 2 m wide branch off the main lode and are termed "flat veins" because of their conformable strike but shallow dip of 45' to 50' toward the northwest. Meteoric water-dominated hydrothermal solutions generated by the Red Mountain stock ascended through intensely fractured, ferruginous

Jan 1, 1988

By Frank E. McCall, John K. Marshal, Fred Garcia

Since the advent of longwall mining systems in the United States, mine operators are increasingly relying on methane drainage techniques to supplement the ventilation system. The most commonly used technique is the vertical gob borehole. The number and spacing of vertical gob boreholes per panel is generally based on experience and underground conditions. To design a more efficient methane drainage systems, mine operators must accurately determine methane gas produced. Thus, mine operators must monitor gas flow and methane gas concentration on every vertical gob borehole on active panels at least once or twice during each 8-hr shift. As the mine grows, it is possible to have more than one operating longwall and many vertical gob boreholes. Thus, daily visits to each vertical gob borehole site can become very time consuming. During weekends when methane gas concentrations typically drop because there is no mining activity, borehole sites may not be visited. To obtain accurate gas flow data, a gob borehole monitoring system was designed and constructed by the U.S. Bureau of Mines (USBM). Gas flow, methane gas concentration, gas temperature, barometric pressure, and vacuum pressure of the exhaust fan are the parameters collected by the system. The system also includes circuitry for automatic shutdown of the exhaust fan and an alarm system before an unsafe condition is created. Telemetry components were also integrated into the system to allow for transmission of borehole data to the mine office. As a test, the system was installed and operated on a vertical gob borehole for six months. Test results indicated that intermittent measurements with hand-held instruments from vertical gob boreholes were always higher than gas flows measurements made by the gob gas analyzer system. This paper describes the system components, operational characteristics, and the results of the test program.

Jan 1, 1995

By Ed Ramsay

The Hill is a cyanidation plant with flotation and roasting. The grinding and treatment have at the present time a capacity of 1400 tons of ore per day and the precipitation has a capacity of 6000 tons per day. The ore is delivered by a 36" conveyor belt and tripper to 8 mill bins having a capacity of 6000 tons. The ore from these bins is discharged onto 20" gathering conveyor belts which are regulated with p.i.v. speed changers to control the belt weight. A weightometer determines the tonnage milled. The feed enters the 8' x 12' rod mill through a rubber lined chute and the product is discharged through a launder to a 7' rake classifier in closed circuit with 10' by 6' hardinge ball mill. Lime slurry is added at the rake classifier to give a strength of .30#/ton. The classifier sand is fed into the ball mill with a scoop feeder and the mill discharge flows in a launder back to the classifier. The classifier overflow is pumped to a 24' by 12' bowl classifier in closed circuit with a 8' by 15' regrind mill. The bowl classifier sands are fed to this mill and the mill discharge is pumped back to the bowl. The bowl overflow at 8% - 200 mesh is the final product from the grinding circuit.

Jan 1, 1975

By J. L. Arola

Since start-up of fluxed pellet production in August: 1987, the Minorca Mine has made a number of process changes to improve pellet quality and productivity. Quality improvements include: 1. Installation of a contraction t:ester. 2. Installation of on-line calcium and silica analyzers. 3. Process autocation changes. Productivity improvements include: 1. A second fluxstone storage bin and feeder. 2. A new vacuum pump and disc filter. 3. A filter aid addition system. 4. Enclosing the filter cake reclaim feeder. 5. A new grate bar cleaner.

Jan 1, 1989

By Edmund J. Flynn

My subject Is Industrial Relations. Thus, I may appear as an intruder at this annual meeting of the Society of Mining Engineers. But I am no more an intruder here than is Industrial Relations in the day-to-day functioning of an engineer either in a staff or a line job. Engineers deal with people, as well as with blueprints, organizational charts, production data, etc. Where you have people, you have emotions, gripes, wants - real or imagined. Or you may just need some people or, at the other end of the pole, you may want to free yourself of people. But whether it is the wants or the needs, the pleasant or the unpleasant aspects of dealing with people, an Industrial Relations Department within an organization is there to help with these human relationships. This is the point for a definition of terns. Reference has just been made to "dealing with people? and to "human relations." This is, precisely the area in which Industrial Relations operates in the western Mining Divisions of Kennecott. In other organizations, what we refer to as Industrial Relations, may be called personnel relations, personnel administration, employee relations, or labor management relations. In our opinion the term Industrial Relations is best descriptive of the activity because it embraces the broad field of human behavior, reactions and satisfactions growing out of an individual?s entire employment relationship including his hiring, his lifetime on the job, and his termination. This is an individual?s industrial life. However, despite the use of the word "industrial", we are ever conscious that Industrial Relations is limited to human relations. Operational activities and decisions relating to the mining, milling, smelting and refining processes are for the line organization. The Industrial Relations interest in these line organizations activities and decisions relates only to the impact they nay have on employees - on people generally within the organization.

Jan 1, 1959

New South Wales (NSW) and Queensland dominate Australian black coal production and exports. NSW produced 86 Mt (95 million st) of saleable coal in 1994, a doubling of output since 1980. Asian demand for thermal and coking coal has driven this growth. This high Asian demand is expected to continue and NSW will seek to secure its share. History The history of the New South Wales (NSW) coal industry can be traced to 1797 when coal was first taken from Newcastle to Sydney (Ellis, 1969). At that time, NSW was a British colony, independent from the other colonies, such as Victoria and Queensland. Australia, as a federation of colonies, did not exist until 1901. The Newcastle coal industry grew through the 1800s in line with the growth of the colonies. Several events spurred demand for Newcastle coal. These included: ? The NSW and Victorian gold rushes of the 1850s and associated population growth. ? The development of steamship traffic at the expense of sail. ? The development of railways and town gas supplies. By 1900, Australia was producing 6.4 Mt (7 million st) of coal, most of it from NSW. By then, NSW had established strong export markets in Indonesia, China, Japan and New Zealand. The history of energy consumption is marked by continual competition, changing intensity of use and substitution. From 1900 to 1940, the Queensland, Victorian and Indonesian coal industries developed at the expense of NSW exports. Similarly, New Zealand developed its hydroelectric industry and thus declined as the largest customer for NSW coal. Oil replaced steam in the shipping and railway markets and electricity replaced gas for lighting. Industrial efficiencies also affected coal. Between 1928 and 1938, coal consumed in generating power fell from by 17% on a kilowatt hour basis and, during the same period, the amount of gas produced per ton of coal rose by 18% (Shaw and Bruno). Faced with these pressures, production and exports stagnated. By 1941, Australian black coal production was 14.2 Mt (15.6 million st). NSW's production was 11.7 Mt (12 million st), up only 19% from 1912. Exports had virtually ceased (Fig. 1). In such circumstances, the industry had lost focus. Unions resisted the need for mechanization, for security of employment reasons, and owners were loath to invest. This reluctance to mechanize and the associated in-

Jan 1, 1997