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Alcoa of Australia's Western Australian bauxite mining operations in the Darling Ranges, south east of Perth, present major challenges in the control of air blast. The close proximity of rural communities and the face profile make the traditional methods of air blast control difficult. An extensive blast noise monitoring programme has been established. The develop- ment of a computerised blast noise prediction model and the establishment of a radiosonde weather balloon facility have reduced blast induced complaints by a factor of ten. The meteorological factors affecting blast noise transmission are discussed and examples are given of adverse weather condit- ions for the south west region of Western Australia.

Jan 1, 1982

By Blight P

There is today widespread concern about the future of the mining industry. In attempting to understand the underlying causes the paper probes in some detail, the long term structural changes affecting growth of metal demand and the development of excess mineral supply capacity. This examination reveals an industry characterised by an unfavourable combination of high barriers to exit and low entry barriers. While rising entry barriers are expected to herald some improvement in the profitability of mining over the next decade, this adjustment is likely to be slow and will require a more economically rational assessment of the industry by corporations and governments Alike.

Jan 1, 1986

By D. R. Nagaraj

The chemistry and structure-activity relationships for four new classes of sulfide mineral and precious metals collectors developed recently are discussed in this paper. These collector classes are alkoxycarbonyl alkyl thionocarbamates and thioureas, dialkyl (or diaryl) monothiophosphates and dialkyl monothiophosphinates. The main emphasis will be to highlight the differences between collectors and their affinities for various minerals on the basis of data on kinetics of adsorption on pure minerals, natural ore flotation and microscopy of flotation concentrates. The mechanism of interaction of these collectors with sulfide minerals is also discussed with the available data on the FTIR and solution chemistry studies.

Jan 1, 1989

By H. W. Renner

The paper industry is an $80 billion/year business that is the largest consumer of industrial minerals. Paper industry generally refers to paper and paperboard products, including pulp mills. Grades and uses of paper and paperboard are very diverse, including such things as napkins, paper plates, corrugated boxes, magazines, newsprint, currency, and copier paper. Only about 40% of paper utilizes industrial minerals as fillers or coating materials. Minerals are used for both functional and economic reasons. Most often, minerals such as kaolin clay and calcium carbonate are used to improve print quality, brightness and opacity of paper. The minerals can be added as fillers into the paper in the wet end of the papermaking system, or can be applied as part of a coating to the paper. Coated papers are the highest quality paper, being used for magazines, advertising brochures and annual reports. Common uses for filled uncoated paper are books, copier paper, envelopes and many of the Sunday newspaper advertising inserts.

Jan 1, 1993

By Bennett McLaughlin

AGNICO-EAGLE started sinking the Penna Shaft in 1995 with a hoisting plant capable of hoisting 1,800 tonnes per day from a 2,240 metre deep shaft. Exploration success lead to the installation of a hoisting plant capable of extracting 4,500 tonnes of ore and 1,800 tonnes of waste per day from a depth of 2,210 metres. The introduction of a new rope selection factor, permitting a safety factor of 4.0, represented the breakthrough required for a cost-effective project. This paper describes the process taken to introduce the new rope selection factor and its impact on the original plant.

May 1, 2001

By T. E. Kobrick

When Ralph Banks called and asked if I would agree to present a paper on environmental health in the coal industry, I was reluctant because I have not been actively involved in coal mine dust control on a day-to-day basis for a number of years. Ralph reminded me that I am one of the few industry people with an industrial health background who remembers the pre-1969 Federal Coal Mine Health and Safety era. This marks the second time within the past year that I have had a similar request based on the same basic reasons. While I was pleased to have been remembered, I'm beginning to feel like the football player who has played one too many games. In responding to Ralph's request to present an overview of the past, present and future of environmental health in the coal industry, I have attempted to take the broad approach of someone who, having been intimately involved in an area of endeavor for a number of years and then leaves, has an opportunity to revisit that area at a later date to see what has changed and what remains the same, what have been the successes and the failures. Since none of us can foresee the future, trying to project too far ahead is fraught with frivolity, except that unless one is foolish enough to accept a future invitation to review those predictions compared to actual events, no one will recall how accurate or inaccurate those projections might have been. I can assure you that I will not ask to accept that challenge, so you can rest comfortably that five years from today you will not be asked to sit through a similar presentation by me - and that's a promise.

Jan 1, 1985

By Flavio Begazo, William A. Enrico

"Southern Peru Copper Corporation's Ilo Refinery, the largest in Peru, began operations in 1975 with a production capacity of 165,000 stpy. Southern Peru bought the Refinery from the state owned Minero Peru SA on June 1, 1994.The Refinery processes blister from Southern Peru's I/o Smelter. Blister copper is processed in an anode plant equipped with two 365 st tilting reverberatory furnaces, a 26 mold casting wheel and an anode press machine. Copper is electrorefined in a tank house equipped with 768 commercial cells, 44 stripper cells, and 40 liberator cells, utilizing two electrolyte circuits and a 21,000 Ampere rectifier.During 1989 through 1994 a program for improving productivity was carried out by increasing the number of cells and increasing current density to the total rectifier capacity. As a result, a capacity 215,000 stpy of refined copper, 2 million tr. oz silver and 6,000 tr. oz gold per year was achieved. In 1994 Southern Peru announced plans to increase capacity to 250,000 stpy of cathode with a US$ 18 million investment and a US$ 2 million investment in environmental improvement projects, as part of the purchase agreement with the Peruvian government.This paper outlines the scope of the SPCC lio Refinery modernization and environmental program. It describes the implementation of the Electrolytic Plant expansion based on instaliation of polymer concrete cells, a new rectifier, a new selenium roaster and a Precious Metal Plant upgrades."

Jan 1, 1997

By W. J. Garmoe

Distinct areas of mineralized and non-mineralized brecciated rock are found in the Ontario Unit of the United Park City Mines. These breccias contain an appreciable fraction of the present ore reserves and probably will become even more important as deeper levels are developed. Three ages of breccia have been recognized in the Ontario Mine to date: ( 1) Pre-mineral breccia that may or may not be mineralized, (2) early post-mineral breccia with mineralized fragments, and ( 3) late post-mineral breccia that is younger than and cuts through ( 1) and (2) above. These age ,relations are known from detailed underground mapping. Locally, both pre-mineral and post-mineral breccias have sufficient lead-zinc-silver content, either as matrix or fragmental material, to constitute ore. Ore-grade breccias occur throughout a vertical range of over 1000 feet and are found in both the Humbug and Deseret formations from above the Ontario 1300 level to below the Ontario 2200 level. The mineralized breccias, which are difficult to distinguish on mine maps, are not well delineated by underground workings, and their horizontal outline and vertical extent are not known beyond the immediate mining areas. The greatest amount of truly mineralized breccia is exposed on the 2200 level.

Jan 1, 1968

By W. McMahon

Following the Sago Mine accident, the Mine Safety and Health Administration (MSHA) asked the U.S. Army Engineer Research and Development Center to study several possible methane explosion scenarios in the Sago coal mine. The study used a 1-ft resolution map of the mine to produce a 3-dimensional (3-D) model of a portion of the mine, including the sealed area where the explosion occurred. An advanced 3-D computational fluid dynamics (CFD) code was used to calculate the explosion pressures within the sealed area, on the mine seals, and in nearby regions of the mine. Based on the best available information on methane concentrations and assumptions on homogeneity and on layering and mix composition, three separate initial conditions of methane-air concentrations and location were studied. This paper discusses the CFD modeling technique, the results of the calculations, the challenges of conducting this type of modeling, and the advantages and limitations of CFD modeling of accident investigations of mine explosions.

Jan 1, 2009

By Nicholas J. Palethorpe

BACKGROUND Before addressing the above topic in any detail, it is pertinent to provide some background on Australia for those people who have not been there or who have a limited knowledge of our continent. Australia is approximately the size of the continental U.S.A. (excluding Alaska) covering an area of approximately 7 million square kilometres. It has a very dry climate which has led to a concentration of people in major cities scattered around the continents perimeter. Australia's population is currently approximately 15 million. Of the work force of 6.3 million, 72% work in tertiary industries, 20.2% in manufacture, 6.5% in agriculture and 1.3% in mining. Agriculture accounts for 46% of exports, mining for 31% and manufacturing for 23,. Economic activity is based on:- Agriculture This is capital intensive and covers extensive areas and is reliant on low cost farming. A.range of foods and fibres are produced with over 70% of production being exported. Such products are of course subject to the usual vagaries of world market demand and market access, particularly in regard to the operation of trade blocks such as the E.E.C. Mineral Resources A wide range of minerals and an abundance of iron ore, coal, gas and uranium resources provide an increasing volume of exports. However, Autralia's oil resources at present only supply approximately 70% of local requirements. Industry This is diverse and encompasses the processing of agricultural products and mineral ores as well as helping to supply the consumer and capital goods needs of the whole community. However, the small scale of local markets, the geographic isolation of Australia and relatively high wage costs have limited the scale of Australia's industry. Advanced technology has overcome some of these difficulties and high tariff and import quotas protect local producers from the full force of international competition. In 1980/81 Australia's Gross Domestic Product amounted to $130 billion with approximately 24% of this being devoted to investment. In the past decade Australia has experienced inflation rates ranging from 5% to 17% and only modest real growth rates ranging from 0.4% to 5% per annum. We have also experienced, as have many other industrialised nations, continuing wage and price increases. Unemployment presently stands at 6%. MINERAL DEVELOPMENT As the above figures indicate, Australia's continuing prosperity is very dependent on the mineral and agricultrual sectors of our economy. The dependence on these sectors is highlighted by the table below which indicates our position in a global context. [Australian Production of Minerals in a World Context Western World % Total Western World Position Mineral Production 1980 1st Rutile 75 Ilmenite 31 Zircon 70 Bauxite 36 Iron Ore 11 Tungsten 14 2nd Lead (Conc.) 15 3rd Manganese Ore 14 Brown Coal 11 (1979) Zinc (Conc.) 10 4thSilver (Conc.) 10 Nickel 6 5th Tin (Conc.) 5 6th Black Coal 5 Gold 2 Source: Mining Annual Review 1981] The total value of all mineral and fuel exports in 1980/81 is estimated at $5.9 billion. This prominence in the world mineral production has largely been achieved in the last 15 - 20 years. In fact, in the early 1960's, Australia had only 2 major mining export centres, Broken Hill in New South Wales and Mt. Isa in Queensland. This growth is highlighted by the fact that in 1963, for example, we exported only 9 tonnes of iron ore and less than 4 million tonnes of coal. In 1980/81 we exported 75m. tonnes ',of iron ore (valued at $1,117m.) and 47m. tonnes of coal valued at $1,965m.). The growth in our mineral industry has come about because of a number of factors. Abundance of Mineral Resources We are particularly well endowed with mineral resources, as indicated below.

Jan 1, 1982

By Robert W. Schaut

The use of micropiles is increasing for new construction and to retrofit distressed foundations in expansive soils. Typical micropiles in expansive soils have a lower section where the micropile grout is embedded in direct contact with the soil, and an upper section that is cased with rigid PVC pipe or other material to reduce the friction between the micropile and the surrounding expansive soil. In the upper cased section, the micropile grout is in direct contact with the inside of the casing. During construction, grout can flow upward into the annular space between the soil and the outside of the casing as the grout is tremied into the micropile. Thus, various interfaces may exist in a typical micropile, including soil-to-grout, grout-to-PVC, and soil-to-PVC. As the surrounding soil heaves, shear stresses are mobilized along the interfaces. The frictional characteristics of the interfaces are design variables that must be evaluated. For this study, an experimental program was conducted to evaluate the shear strength of the three interfaces listed above. Conventional direct shear testing was performed at a commercial testing laboratory. In addition, specialized testing was performed at Colorado State University (CSU). For the CSU testing, an interface testing protocol was designed using a modified triaxial cell to allow evaluation of the interface characteristics between rigid PVC and cylindrical specimens of grout or clay soil. It is shown that the shear strength of the soil-to-PVC and grout-to-PVC interfaces are similar, both of which are significantly lower than the shear strength of the soil-to-grout interface. This indicates that the use of a PVC casing in the upper portion of a micropile has a positive effect in reducing friction and the shear stresses resulting from expansive soil.

Jan 1, 2011

By Jacque Turgeon, Gontran Foy

"The Mineral Research Centre of the Quebec Department of Energy and Resources has worked extensively on the development of a dry process to extract pure mica flakes from a phlogopite ore. The liberation of mica from the gangue is effected basically by impact crushing, and the ground ore is screened into several fractions, each having a fairly narrow range of grain size. Each sized fraction is then fed to an air separator where heavy grains are separated from light flaky grains. Heavy fractions are returned to hammer mills where gangue minerals are ground finer and blocky mica particles are exfoliated. A second stage of screening is performed and each fraction is sent to an air separator. This sequence is repeated until mica products are virtually free of gangue. These different fractions are then treated in a cage mill in which mica flakes undergo a more orderly exfoliation along cleavage planes. The ground mica is again submitted to a final screening stage, after which each fraction constitutes a final commercial product.This process permits the recovery of about 70% of the mica contained in the ore. The over-all process will be described along with technical details of each unit operation. Recent work on a wet grinding method to produce very fine mica will also be discussed.IntroductionRecords of production of mica in Quebec date back to 1886. Production has been more or less continuous since that time, with peak activity during the war years. Production was interrupted in 1966, but started again in 1972 when Marietta Resources and Laviolette Mining and Metallurgical Corporation started their joint operation in Canton Suzor, northwestern Quebec. Mica deposits of more or less importance exist in different parts of Quebec, of which three have attracted attention in recent years: the Canton Suzor deposit, the Canton Lamy deposit and the Canton Chasseur deposit. The Suzor orebody was first identified by Carl Faesler in 1936, who described the rock as ""brown biotite in flakes half an inch in diameter, with interstitial augite, apatite and feldspar""."

Jan 1, 1982

By C DahnTr-Lindqvist

The Kiruna mine produced about 19 Mt processed iron ore in 1999 using sublevel caving. General failure in the hangingwall has been widely studied and its mechanism is rather well understood. Failure in the footwall is more recent and not perfectly explained. Plane shear failure and Hoek and BrayÆs circular failure charts were successfully used to match the first surveyed failure surfaces. The footwall is not free yet but covered by a caved waste rock abutment whose exact behaviour is poorly known. Based on new field data and numerical models (FLAC), the following paper presents recent improvements in understanding the Kiruna mineÆs footwall failure process.

Jan 1, 2000

By E. J. McGuire, E. W. Brickle

INTRODUCTION Several recent technological improvements - largely by the convey-or industry - have increased the importance of inclined shaft construction for developing mines where ore deposits are relatively shallow. With these newer systems, long conveyor haulages are economically feasible, allowing mine owners to justify the expense of the inclined shaft or slope. What this actually means is that they can now take advantage of the versatility this construction offers. For example, haulage capacity can be changed by conveyor additions or replacements; equipment can be trammed to and from the surface quickly without costly breakdown and re-assembly; and a walkway is available for workers in the event of an emergency. Now, another innovation may accelerate this type of construction, the use of tunnel boring machines or "Mechanical Moles" to dig the slopes. While conventional. drill and blast methods have been used previously to build inclined shafts, the tunnel boring machine technique offers greater production rates, higher safety and a better, much cleaner bore. McGuire Shaft & Tunnel Corporation of Ft. Smith, Arkansas recently started such a slope project - the first ever bid by a contractor based on the use of a "Mechanical Mole".

Jan 1, 1997

By Larry D. Patts

Section 317(e) of the Federal Coal Mine Health & Safety Act of 1969 directed the Secretary of the Interior to prepare standards under which all working places in a mine shall be illuminated by permissible lighting while persons are working in such places. Section 317(e) further provides that such working places shall be illuminated within 18 months after such standards are promulgated. In accordance with this section of the Act, there was published in the Federal Register for December 31, 1970, a notice of proposed rulemaking which prescribed the illumination to be provided in the working places of underground coal mines. In light of written comments, suggestions, and objections to this proposed rulemaking, the proposed standards were withdrawn and reproposed in the Federal Register for Wednesday, October 27, 1971. In light of further comments, suggestions, and objections, a public hearing was held on April 4, 1974, and standards were again reproposed and published in the Federal Register for April 1, 1976. Promulgation of the final lighting-standards &k place on October 1, 1976, which means that the underground coal mining, industry must comply with face illumination requirements by April 1, 1978.

Jan 3, 1978

By Frank Ladwig, Stephen Gos

Tailings and/or wastewater generated from gold extraction plants employing cyanida­ tion must often be treated to remove the cyanides and heavy metals for environmental reasons and/or gold extraction inhibition reasons, due to the presence of heavy metals like copper, which have a detrimen­ tal effect during cyanidation. In recent years, the treatment of effluents contain­ ing cyanides and heavy metals has been widely studied, Among chemical treatment methods, the use of hydrogen peroxide has been universally employed as a viable option. However, in some cases, effluents containing high concentrations of heavy metals and/or solids decompose the hydrogen peroxide, an undesirable side reaction. The addition of stabilizers or other peroxygen compounds together with hydrogen peroxide can, however, considerably reduce the rate of decomposition and thus result in detoxi­ fication costs, which are considerably less than the standard detoxification process using hydrogen peroxide. In some cases, the reaction rate can also be increased, resul­ ting in lower investment costs for new detoxification plants. This paper deals with the results of developmental work performed in the recent past and introduces some new processes with the aim of optimizing reagent consumption and costs.

Jan 1, 1992

By Kathryn C. Sole, Angus Feather, Leslie J. Bryson

A novel solvent-extraction route for the production of high­purity gold has been successfully demonstrated on a pilot-plant scale, and the first full-scale production plant is being commissioned. This plant, at Harmony Gold Mine in South Africa, is designed to refine 24 tons of gold per annum when operated for one shift per day. The commercial implementation of this process represents not only a significant advance in gold­refining technology, but may also be instrumental in initiating important changes in the legislation regulating the marketing of gold in South Africa. The Minataur™ Process (Mintek Alternative Technology for Au Refining) is able to produce gold of either 99.99% or 99.999% purity from intermediate process products having a wide range of gold contents. The process comprises oxidative leaching of the feed material, followed by selective solvent extraction of the gold from the leach liquor to reject impurities, and then precipitation of high-purity gold powder. This paper introduces the process, presents selected results of pilot-plant trials in which high-purity gold was produced from two significantly different feed materials, and illustrates some of the applicable cost benefits.

Jan 1, 1997

By J. E. Cressman, Raj Devarajan

The declaration of bankruptcy by the operator (Summitville Consolidated Mining Company, Inc., SCMCI) of the open pit heap-leach operation at Summitville and the subsequent takeover of the minesite by the USEPA has been a high profile and largely painful event for the mining industry. Shadowed by the ovrall picture has been a continuous effort by technical and operational personnel to treat contaminated water and improve water quality while satisfying various management strategies and budgetary constraints. Summitville's operations history can thus provide a body of knowledge potentially beneficial to operators and managers of present and future mining projects presenting challenges from similar geology, mineralogy, topog­raphy, climate, water chemistry, financial and regulatory ele­ments. This discussion focuses on water treatment operations that occurred at the minesite, initially as part of mining production and reclamation, and later as part of USEPA's emergency response and remedial efforts. All of the treatment efforts have targeted the cyanide and metals contamination associated with process waters from the heap leaching activities, and acid mine drainage (AMD) containing metals such as copper, iron, alu­minum, manganese, and zinc in high concentrations.

Jan 1, 1996

By C. Geenen

At its Olen site, Union Minière Copper operates a new full-size deposit tank house. A first 200,000 t/y module was commissioned in October 1996, and an additional 130,000 t/y unit started in April 1998. The main objectives of the new tank house project were to produce grade A cathodes starting from anodes with a wide range of compositions and at a minimal operating cost. The tank house uses Isa Process technology. Based on the process parameters agreed upon with MIM, UM Copper developed the basic design and UM Engineering was the in-house contractor for the engineering. The new tank house is equipped with advanced technology polymer concrete cells, automated two-bale cranes and high-capacity machines. The first 200,000 t/y module treats anodes with a more conventional composition at 330 A/m2; the second 130,000 t/y module treats anodes with a high slimes fall (12- 13 kg/t) at current densities up to 285 A/m2. After some teething problems, the new tank house is meeting all set targets. This paper illustrates and comments on the design characteristics and operational results.

Jan 1, 1999

By Jan M. Mutmansky, David R. Kalasky

Computer simulation continues to be one of the most successful analytical applications of computers in the mining and mineral processing industries throughout the world. Through simulation, managers and engineers can explore the impact of new technologies, equipment designs, plans and operating strategies to improve their operations. It is not uncommon for a single simulation application to provide a quick payback of analysis expenses (within weeks or months) yielding long-term financial and operational dividends. The paper will present a summary of the types of software systems that are available for use on PCs and other computer systems. Support software for curve fitting, statistical analysis, and optimization of simulation models will also be presented. Methods of leveraging simulation efforts through networking and coupling of software systems will be discussed. Finally, the trends in simulation in the mineral industries will be analyzed. Areas of strength and weakness of simulation will be discussed along with the usefulness of commercial general-purpose and custom-writ- ten simulation packages. The future possibilities for simulation in the mineral industries will be outlined and predictions on trends for the future will be presented.

Jan 1, 1996