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By W. David Tyler

Any mining or engineering-construction excavation that extends below the water table must be dewatered. In many situations, the ground is of low permeability or the workings extend only a short distance below the water table. So water removal can be handled easily and economically by using mobile centrifugal pumps. However, there is an increasing number of mines that have a continuous high flow of water into the workings. Controlling this flow can significantly increase the cost of ore production. Successful implementation of any major dewatering scheme will ultimately rely on a clear understanding of the local geology. This understanding is necessary before an interpretation of ground water conditions can be made. It will dictate which dewatering methods are feasible. Once the geology and the ground water system are known, the scope and timing of the dewatering measures can be varied with the mine plan. Ground water modeling can assist in optimizing the dewatering system, though the precise objective of each model should be clearly defined. Production wells must be sited and drilled so that individual well efficiencies are high. Any lost efficiencies will translate into higher operating costs. Each well must be designed for maximum long-term control of the water table, and pumps sized to operate under continually changing heads. Finally, the investment in each production well must be protected during the mining process.

Jan 1, 1991

By Douglas J. Lacke

1974 marked the start of a new era for Climax Molybdenum Co., a division of AMAX, with the initiation of an open pit operation above the existing successful underground block panel caving mine. A number of problems posed a challenge to the Climax open pit. Highly fractured rock, old mine workings, permafrost, and more than 7.6 m/a (300") of snowfall forced changes in normal operations. Final pit wall design was altered. Production bench heights were lessened due to old workings. These and other modifications contribute to a highly successful open pit operation.

Jan 1, 1981

By Warren D. Stanford Stanford

Introduction The Sleeper mine is a near-surface gold mine located in a remote area 56 km (35 air miles) northwest of Winnemucca, NV (Fig. 1). The deposit was discovered in 1984 by an Amax exploration geologist. Favorable drilling results led to feasibility studies and metallurgical testwork. Final evaluation of the mine potential proceeded very quickly. The project received Amax board approval in July 1985. Eight months later, the process plant was fully operational. The first gold ($1 million) was shipped one month later, in March 1986. Total plant capital was $27 million. Payback was achieved in six months. The Sleeper mine was expected to produce 1.6 t (53,000 oz) of gold and 1.3 t (41,000 oz) of silver annually. However, the ore body exceeded all expectations. Production for the first 10 months of operation amounted to 4 t (128,000 oz) of gold and 2.9 t (94,000 oz) of silver. Direct cash operating costs are in the $1.77/g ($55 per oz) range. Amax is actively conducting exploration nearby for additional reserves to extend the mine's life. (See update on page 242.) Geology The Sleeper gold deposit is located on the northwestern flank of the Slumbering Hills and in the Awakening Mining District. Rocks exposed in the vicinity of the deposit are interbedded siltstones, sandstones, and limestones of Triassic age. They are overlain by latite lava flows and tuffs of Tertiary age. Dikes and sills of latite and andesite intrude the sedimentary rocks. Quaternary deposits of mostly sand with minor gravel and clay cover a pediment containing the gold deposit. The sedimentary and volcanic rock units have been transsected and offset by extensive north- northeast trending faults and less abundant northwest trending faults. Both fault systems fractured and prepared the ground for subsequent invasions of mineral-bearing hot spring geothermal waters. The hot spring systems produced widespread hydrothermal alteration and gold mineralization at silicified centers near feeder fault structures. The deposit is hosted by siltstone and latite that have been hydrothermally brecciated. The main breccia is elongated north-northeasterly. The hydrothermal breccia zones appear to dip steeply to the west. Gold mineralization consists of native gold and electrum deposited in two or more high-grade quartz-breccia veins. Lower grade gold mineralization occurs

Jan 4, 1987

By M. K. Gangal, E. D. Dainty

CANMET/MRL has been contributing to an industry/government program to assess the quality of air in mines, and improve the working environment for Canadian miners. The ultimate aim of this program is to recommend a sampling methodology and appropriate concentration limits for both the soot (diesel particulate matter - DPM) generated by diesel equipment, and respirable combustible dust (RCD) as measured underground. The program was conceived by the Canadian Adhoc Diesel Committee, which consists of representatives from seven major Canadian mining companies, three provincial inspectorates, one union representative, two manufacturers of diesel equipment, and CANMET, a Federal Canadian research agency. This paper describes the modification and laboratory confirmation of an existing methodology for the sampling and analysis of DPM/RCD, including: sampling problems, filter selection, filter efficiency, DPM size distribution, the approximate performance of fractionating devices, and it reports the results of current ambient measurements of exposure levels in Canadian underground mines. Because of the concern about the health impact of DPM/RCD on mine workers, North American agencies are in the process of establishing limits for these aerosols. So far, the Province of British Columbia is the only jurisdiction in North America to legislate the maximum exposure level of RCD in its underground mines, i.e. 1.5 mg/m3 interim level recommended by the Adhoc Diesel Committee. It has also recommended the use of the CANMET/ADHOC RCD sampling protocol.

Jan 1, 1993

By Edward O. Reinbold

The paper presents the results of a study which involved collection and analysis of airborne pollutant concentration data in two producing underground room and pillar metal mines which use diesel powered equipment in the area near the face. The results include the concentrations of CO2, CO, NO, NO2 and respirable particulate matter measured with the latest portable instruments, and the carbon and hydrogen contents of the particulate matter samples determined by combusting them in a Elemental Analyzer. The carbon and hydrogen contents are used to estimate the amount of diesel particulate matter in the mine ambient air. The short term grab sample concentration data, although not suitable for determining compliance with ACGIH Threshold Limit Values (TLVs), are related to the TLVs so that they may be compared conveniently. Lognormal frequency distributions and the arithmetic mean of the concentration measurement data are used to compare different mine situations. Conclusions are drawn as to which pollutants are most important to control under actual mine production conditions.

Jan 1, 1979

By J. W. Choung, J. A. Finch

Acid rock drainage (ARD) is a recognized environmental challenge facing mining industries. An ambient temperature ferrite (ATF) process has been investigated for treating ARD. Most nonferrous metal and calcium ions present in typical ARDs were found to be detrimental to the ATF process. Three approaches were examined, including C02 aeration, addition of complex agents and use of magnetic seeds. By introducing magnetic seeds in the ATF process, the interferences were minimized and all the precipitates formed with lime neutralization were magnetically recovered from a simulated ARD. The residual concentrations of major metal ions in the treated water were environmentally acceptable. The XRD pattern confirmed the spinel ferrite crystal structure of the products

Jan 1, 2000

By John Zeni

In Australia during the 1990s, Zeni Drilling took on several demanding shaft boring contracts. This paper describes the safety, operational, technical and environmental advantages derived through the implementation of mechanized boring methods for two of these projects. The paper first describes a 3-meter (10 ft) diameter access shaft blind bored from an underground location to 440 meters (1,444 ft) deep for a gold mine in Tasmania. The construction of a 5.8-meter (19 ft) diameter, 515-meter (1,690 ft)deep ventilation shaft for a longwall coal mine in New South Wales is also described.

Jan 1, 2001

By Tim Neil, O&apos

The coming years should see moderate growth in the US coal industry. That growth may come at the expense of the oil and natural gas industries. Conoco pegs coal growth at 2% a year, until the year 2000. During that same period, Conoco projects only 0.5% annual oil growth and "a flat or negative trendline" for natural gas. This is compounded by the fact that coal has a delivered cost per Btu that is only half as much as it is for natural gas and only a third as much as it is for oil. So said Ralph Bailey to many of the 2600 attending the opening session of the American Mining Congress Coal Convention, May 12-15, in Pittsburgh, PA. Bailey is chairman of the AMC. He is also chairman of Conoco. While coal's projected growth is not spectacular, "it is in fact almost an assured growth," Bailey said. Weak oil and gas prices will likely prevent faster growth for US coal. Most of coal's increased demand will come from the electric utility industry and expanded steam coal exports. Conoco's study projects that domestic coal demand will be strengthened in the 1990s. By then, the present surge of nuclear power plant constuction will be over. And there will be a lack of acceptably priced, large-scale generation alternatives for utilities. "It is not likely that any electric utility is going to be ordering new nuclear reactors," Bailey said. "And as oil and gas supplies become scarcer and more costly, it is only logical that coal is going to fill the gap." At the same time, Bailey believes the US coal industry must find ways to lower its costs. He said cost excesses can be found in "regulatory overkill, labor, and simply bad habits" hidden by years of high inflation. "Those costs have now been laid bare, because we are going through a pe¬riod of disinflation. We have to put our house in order, particularly if we are going to compete in world markets." Bailey also touched on coal research. "The industry certainly accepts the fact that we must find a way to burn coal as cleanly as possible. A lot of work in that regard is going on. I expect there will be some significant break-throughs." Bailey said the coal industry is being squeezed this year. Last year, coal customers accumulated inventories in anticipation of a major coal strike that never materialized. Now, many utility customers are working down these inventories. So they are not taking deliveries on their coal contracts. But coal use is up in 1985, compared with 1984, Bailey said. So increased coal use, along with supply drawdown, should strengthen the coal market before the year is out, he said. After Bailey's presentation, some 100 speakers addressed policy and technical topics at 15 sessions during the four-day meeting. It was the first time since 1977 that the AMC Coal Convention has been held in Pittsburgh. And this year's attendance was up 40% from the last AMC Coal Convention held two years ago in St. Louis, MO. This year's registrants included 228 companies, 225 manufacturers, and 106 associated members. The only negative was the David Lawrence Convention Center. It was less than ideal. By turns, meeting rooms were too small, too cramped, or too far from one another. The session on longwall mining was so crowded that the doors were propped open so conference delegates could peer in. A concurrent manufacturers' forum session needed 50 more chairs to accommodate those wanting to attend. However, on to summaries of some of the presentations. Coal transportation and export Since Congress approved the 1980 Staggers Rail Act, railroad rates for hauling coal have not been excessive. In fact, rail rates for coal have increased less than 0.5% a year, in real terms, since 1980. Moreover, the market oriented principles written into Staggers are contributing to the improved financial and operational health of the nation's railroads. But no railroad is earning excessive profits. That is the gist of a coal transportation study being completed by the US Department of Energy. William Vaughan is DOE's assistant secretary for fossil energy. He affirmed the thrust of the upcoming report. Vaughan did allow that Interstate Commerce Commission (ICC) regulations on rate reasonableness could permit the railroads to exploit their monopoly power on captive shippers. Luncheon comments later made by Don Hodel confirmed Vaughan's comments on railroad rate justification. Hodel is Secretary of the

Jan 7, 1985

Though the mining industry is beset with problems-a broad slump in metal prices, a rash of acquisitions and takeover attempts, rising capital costs, and an aggressive Canadian energy program-there was an under-current of optimism at the 1981 AMC conference that's been missing at industry meetings in recent years. The industry anticipates a turnaround in the 1980s, buoyed perhaps by the new spirit of cooperation from the Reagan administration. For the first time in years, it appears that Washington and the mining industry share mutual goals for developing the nation's resources. A number of prominent Reagan officials were on hand during the three-day conference in Denver, September 28-30, to reassure conferees that restrictions plaguing energy and minerals development would be eased. Interior Secretary James Watt and other government speakers promised cooperation in bringing balance to federal public lands policies, a review of regulations that have hampered the industry, and prompt action on domestic minerals policy. Daniel N. Miller, Jr., assistant interior secretary for energy and minerals, said, "It is our intent to dismantle the overhearing bureaucracy that has stifled mineral and energy exploration. We know that Interior's rules have shackled the mining industry in recent years, and we know that those rules must be eased." Miller noted that the administration will not permit mining on national park lands or wildlife refuges, but added that "we must assess a variety of uses of public lands ... we will restore lands to multiple use where practical." EPA administrator Anne Gorsuch assured industry representatives that the administration intends to work within environmental laws and with Congress to review and revise water, soil, and air pollution policies. "We have a strong commitment to see that there are major mid-course corrections" of air regulations, Gorsuch said. Support from these "new friends in Washington" will be crucial in light of the serious problems pressuring the industry. Copper prices have plunged to almost three-year lows and prices for molybdenum, gold, and silver have slumped. Earnings are down and today's high interest rates prevent a quick turnaround. Companies are on edge after the recent takeovers of Kennecott, St. Joe Minerals, and Texasgulf Though the companies may benefit from the major injection of capital that large energy firms can provide, many observers fear the new parent companies won't be willing or able to survive the cyclical metal markets. Arco and Gulf Resources, for example, have been criticized for closing Anaconda's Montana copper facility and the Bunker Hill unit in Idaho, respectively. Canada's national energy program has brought additional pressure on the industry. This policy, which emphasizes Canadian majority ownership of the country's energy sources, resulted in acquisition of Texasgulf's Kidd Creek lead-zinc-silver complex by Canadian and French interests. In response, the American Mining Congress adopted two resolutions on takeovers. One calls for the US government to review laws regulating tender offers and takeovers "to better ensure that principles of fairness and sound investment policy govern such transactions.'' The other asks the government to demand "fairness and reciprocity" as a basis for US policy governing international trade in minerals and investment relations with other countries. AMC's shopping list included four other priority goals, aimed primarily at the Interior Department: • Prompt implementation of Interior's efforts to bring order and balance to rules governing access to public lands for exploration and development. • Statement by the President of a comprehensive and coherent domestic minerals policy. • Amendment of the Clean Air Act to remove impediments to productivity and barriers to economic development that are not necessary to essential goals of the act. • Development of new approaches to better achieve worker health and safety in the most cost-effective manner without penalizing productivity. Almost 6000 mining industry executives attended the 1981 convention-the largest in AMC's 84-year history. As in years past, the conference offered a wide spectrum of presentations-nearly 100 papers in 26 sessions-ranging from commodity forecasts to the latest technical achievements. New Administration Stockpile Goals The minerals availability session included a presentation on management of the minerals stockpile by Paul K. Kruege r of the Federal Emergency Management Agency. Krueger notes that rather than providing incentives for development of a domestic raw materials industry, the government has "a history of providing disincentives to industry." In mining industries, he adds, the rate of productivity growth has been -6% over the last six or seven years. Krueger feels there will be a major change under the Reagan administration. In March 1981, FEMA began the first purchase program for the national defense stockpile in over 20 years. The stockpile is sadly out of balance, Krueger adds. Stockpile materials are

Jan 12, 1981

By Gary Krix

The Amdel Thickener Interface Gauge (TIG) provides continuous on-line measurement of the level of the liquid/solid interface in thickeners and Counter Current Decantation (CCD) washers. Unlike other interface level measurement systems, the TIG also determines the span of the transition zone. The transition zone is the region between the clear liquid overflow zone and the compressed solids zone. The Thickener Interface Gauge determines the level of the interface by measuring the natural radioactivity of the solids in the thickener tank using an array of up to twelve detectors mounted vertically in a stainless steel probe. All solids contain low levels of natural radioactivity while the liquid phase generally does not. The concentration of natural radioactivity at each level in the thickener therefore depends on the concentration of solids. The radiation emitted by the solids is converted to electrical pulses by the detectors in the probe and the pulse-rate provides an accurate measurement of the density. A typical count-rate profile is presented in Figure 1. The vertical axis indicates the depth in the tank referenced to the surface of the liquid. The horizontal axis indicates the count-rate measured by the TIG probe, this count-rate is proportional to the density and can be used to determine the settling rate. The count-rate at the top of the graph is relatively low, this region corresponds to the clear overflow zone which contains virtually no solids. Moving down the vertical axis the count-rate increases dramatically at the level of the transition zone where the solids content increases with the depth in the tank. In this region the settling conditions of the solid particles change from free settling to compression. Moving further down the vertical axis the count-rate reaches a plateau where the count-rate remains relatively constant although there are often small fluctuations, this region corresponds to the solids compression zone. The liquid/solid interface as measured by the TIG corresponds to the depth at which the count-rate crosses the target count-rate which is generally selected to be midway between the liquid count-rate and the compressed solids count-rate. The length of the TIG probe is selected to cover the typical operating range of the liquid/solid interface in the thickener or washer. If, for example, the minimum bed level is 3.0 metres below the surface of the liquid then the probe length is selected to extend 30 metres below the surface. The TIG probe can include up to twelve detectors and the se are spaced over the measurement range. For small measurement ranges of around one metre 4 to 6 detectors would normally be used while for larger measurement ranges of three metres or more twelve detectors would be supplied.

Jan 1, 1993

By Carl P. Maronde, William P. Barnett, Patricia A. Rawls

The commercial deployment of advanced fine-coal cleaning technologies depends on cost-effective approaches for efficient separation and ancillary operations in handling, dewatering, drying, and transporting coal fines. As a result of two solicitations under the High-Efficiency Preparation component of the Department of Energy Coal Preparation Program, several projects were initiated for testing and evaluation of emerging technologies and equipment that address operational difficulties associated with coal fines. This paper will update the status of those projects and discuss how the technologies they represent can ameliorate some problems associated with coal fines in today's preparation plants.

Jan 1, 1995

By J. E. Lema

America's bulk commodity transportation systems have taken on a new look in the 1970's and 1980's. Railroad systems, barge lines providing inland and intra- coastal waterway transportation, and Great Lakes carriers have undergone substantial changes through mergers and acquisitions, consolidations of ownership and control, and construction of modern intermodal transportation facilities linking railroads and water carriers. The new look has generated some concerns and opportunities with regard to producers and shippers of bulk commodities which are characterized by the necessity of moving large quantities of heavy materials long distances. Clearly such transportation requirements call for efficient railroad and water carrier services. Shippers of commodities like coal, grain, .chemicals, minerals, ores, forest products, petroleum products, and heavy manufactured goods find reductions in transportation competition lead to concerns that rates charged by carriers will not be sufficiently constrained by market forces. At the same time, new policies on contracting for railroad services can lead to greater efficiencies, a rewarding opportunity for carriers which should be shared with shippers and consumers of bulk commodities. Then, of course, there's a related problem that in the absence of effective competition, the benefits of increased carrier efficiency will not be passed on, in part, to shippers and consumers, causing losses in markets for producers.

Jan 1, 1986

American Barrick Resources Corp. has come farther, faster in the last 11 years than any mining company in recent memory. Acquisition of Lac Minerals Ltd. in August 1994 now makes Barrick the largest gold producer in the world outside South Africa. In terms of market capitalization, the company is the world's most valued gold producer. American Barrick's 28.3-km2 (7000acre) Goldstrike property on Nevada's Carlin Trend, the primary engine for past growth, was purchased in 1987 for $62 million. Regarded as an attractive exploration target, Goldstrike instead propelled American Barrick to the front rank of world gold producers. In 1993, the company produced 50.75 t (1,631,988 oz), 44.78 t (1,439,929 oz) from Goldstrike. Reserves on the property totaled 905 t (29.1 million oz) at the end of 1993, the largest in North America.

Jan 1, 1994

By S. Schina

Part of the Imittos Western Peripheral Motorway in Athens is the twin road tunnel in the vicinity of American College, with 20m excavation diameter. In the paper, the environmental and other requirements, the geometry and the geological – geotechnical characteristics of the rock formations in the construction area are given. Information regarding the modeling and analysis methods that are used for the design of the temporary support, the final lining and the wedge and slope stability analysis is described thoroughly. Finally, the results of the analyses are compared with these of measurements and general remarks during the construction of the tunnels.

Jan 1, 2001

The 28th annual American Mining Hall of Fame Awards Banquet and fundraiser sponsored by the Mining Foundation of the Southwest will be held at the Marriott University Park Hotel, Tucson, AZ on Saturday, Dec. 4, 2010. The Mining Foundation of the Southwest is a nonprofit organization whose objectives are public education about the mineral industries, and recognition of outstanding accomplishments in and contributions to the fields of mineral and fuel resources. Funds are being raised to the support the foundation?s educational programs. Among these is the Educational Outreach Program operated jointly by the foundation and the Arizona Department of Mines and Mineral Resources.

Jan 1, 2010

By Frank W. Luerssen

Introduction "Austerity" is perhaps an overly generous description of the past three years in the American steel industry. Steel plants operated at an average of only 57% of their capability in 1982-84. The dismal losses for last year are still being totaled. But during the two years before this period, American steelmakers recorded an aggregate net loss of a staggering $6.8 billion. Steelmakers responded by closing numerous marginal facilities. And production capability was cut by 13.6 Mt (15 million st). Capital expenditures still averaged $2 billion annually. But this was inadequate to maintain the existing base of steelmaking facilities. The general economy experienced a satisfactory recovery during this period. American steel, however, continued to suffer from a lagging recovery in the capital goods sector. This was due to record penetration of its domestic market by imports and from very weak realizing prices on the volume that was available. In addition to the direct influx of offshore steel products - which itself depressed prices - the industry also became painfully aware of the growing importance of "indirect" imports. These came in the form of steel-containing producer and consumer durables. Industrial equipment and autos fabricated from foreign steel accounted for the equivalent of 6 Mt (6.5 million st) of lost market opportunity for domestic steel-makers last year. That is over and above the 23.5 Mt (26 million st) of direct steel imports. Given these factors, Inland Steel was not spared from the threeyear downpour of red ink. Despite its record of continuing modernization in steel, our single-plant location in the world's best steel-consuming market, and the high proportion of consumer durables related products, such as cold rolled and coated sheet in our mix, Inland suffered aggregate losses of $277 million during the 1982-84 period. Strategic Planning The foregoing establishes a perspective - a base from which we have restructured our view of the steel industry, and of our own role within that picture. Until possibly two years ago, this present weakness in steel demand was viewed around the world as an aberration, eventually to pass. By contrast, it is now recognized that austere times are the normal steel environment. The topic here is management of resources. This implies an emphasis on strategic planning. It is worthwhile to examine some of the more critical assumptions that were driving strategies among a number of steel companies just before the 1980s. Those projected characteristics of the future steel environment were arrived at through painstaking analysis. They were carefully and heavily quantified and were generally shared by outside observers and our peers within the steel industry. • First, the assumption was made that domestic steel demand would continue to grow at an average rate of 2% per year. • Second, it was assumed that this growth in the American market would continue to be filled predominantly by US mills. It was believed that increases in steel and steel-related demand overseas would absorb much of the ominously growing capacity of third

Jan 6, 1985

By M. E. Grimes

The Port Radium mine of Eldorado Mining and Refining Limited, located on Great Bear Lake only a few miles from the Arctic Circle in north-western Canada, is the oldest uranium producer in Canada, The first concentrates were produced in 1933 and except for a period between 1940 and 1942 the mill has operated continuously. Although it is located in a remote area, and compared to more recent mines in other areas is a small tonnage operation, nonetheless the relatively high grade of the Port Radium ore has permitted operation to date on an economical basis. The mill process at Port Radium includes the original gravity concentration mill, and since 1952 an acid leaching plant which treats tailings from the gravity mill and tailings recovered by dredging of residues from underwater dumps in Great Bear Lake. The pregnant solution from the leach plant has to date been processed through aluminum reduction to yield an intermediate grade uranous phosphate-arsenate precipitate, Because of the rising costs of the aluminum reduction process, and its sensitivity to ore composition, Eldorado became interested in possible application to Port Radium of the solvent extraction processes of which we were obtaining increasing information in the latter part of 1954 and during 1955.

Jan 1, 1958

By Gary W. Hudiburgh

The gangue in some magnetite ore bodies contains feldspar; the alkali content of the feldspar reduces the usefulness of these iron ores. One method of decreasing the feldspar content in magnetite concentrate is froth flotation. The amine flotation of feldspar from magnetite concentrate was investigated using zeta potential measurements, Hallimond tube flotation tests and laboratory-scale flotation tests. The zeta potential of various feldspars (microcline, albite, anorthite, oliqoclase and anorthoclase) were determined as a function of pH; the point of zero charge ranged from pH 1.4 to 2.5. Hallimond tube flotation tests using two amine reagents were conducted on the feldspars. Hallimond tube flotation tests using six amine flotation reagents were performed on the cobber tails (quartz, albite and microcline) from a magnetite concentrating plant; in all cases, over 85 percent flotation recovery was obtained at pH 8 and 10-5 to 10-4 [M] collector addition. Laboratory-scale (667 grams) flotation tests were performed on the magnetite concentrate in an attempt to float the feldspar which had reported to the concentrate. The effects of three different collectors, two levels of collector concentration, three pH levels, starch and HF acid were investigated.

Jan 1, 1975

By M. G. Gorman

The effects of particle size, particle shape and degree of aggregation on n-dodecylamine flotation of -20 µ m quartz and glass beads were studied. A microflotation cell suitable for use with very fine particles was used in the flotation experimentation. Degree of agglomeration of particles was estimated by comparing size distributions of the quartz and beads in a dispersed system to size distributions in systems in which the collector was present. Results obtained show that in such flotation systems the fine particles are not generally present as individual particles during flotation but rather as aggregations. However, the quartz floats more readily than the beads indicating that there are some shape effects in the systems, considering the large specific surface areas of the materials it also appears that substantial amine consumption in the systems may limit flotation or lead to a requirement of greater reagent dosage for equivalent flotation to that tor larger particles.

Jan 1, 1990

By Paul G. Greenhill

The Australian Mineral Industries Research Association (AMIRA) was established by the Australian mineral industry in 1959 to develop and manage collaboratively funded research projects. Owned and managed by industry, it coordinates research that answers questions defined by the sponsoring companies of the projects. Now over 35 years old, the Association is an excellent example of what can be achieved through collaborative research and an industry - backed research organisation.

Jan 1, 2000