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By R. A. Ynchausti

In January 1993, Pyramid Resources began implementation of a supervisory expert control system at a U.S Cu concentrator. The objective of this control system was to improve plant profitability through unit operation optimization and integration. This paper documents the key aspects of the project, including: economic and associated benefits, system architecture, concepts of implementation, process control strategies, practical aspects of implementation and conclusions. The implementation of expert control at this concentrator has resulted in an estimated benefit of $50,500 per day. This is a net result of improved tonnage, reduced reagent consumption, improved concentrate grade and reduced energy per ton produced.

Jan 1, 1995

By T. BACHMANN, G. SHAPLAND, E. Amini, N. BEATON, M. BECERRA

Process plant modeling in the computer environment has been developed over the past 40 years by implementing the comminution models formed by the Julius Kruttschnitt Mineral Research Centre, University of Queensland, in the early 1970s. The models for the other processes in a mine value chain, such as blast fragmentation and flotation, were continuously developed and improved in parallel as well. Other research and commercial entities have also developed process modeling methodologies in the computer environment, which evolved as specialized commercial software or through equations set up in Excel spreadsheets. These were performed on a local computer, in thousands of simulations over a long period of time due to hardware limitations and the lack of a fully automated process. This limits the application of detailed process simulations for scale-up and strategic planning analysis, as they require many simulations to cover all possible scenarios which would take a lifetime when using local computers. The Integrated Extraction Simulator (IES), as the next generation of cloud-based software package, has made it possible to run simulations on the entire operation value chain in the same platform, including drilling and blasting, crushing, grinding, flotation, and other downstream process and material-handling units. This capability has allowed IES to handle multivariable simulations across the mine value chain, including pre-concentration and in-pit size reduction, and modify the process simultaneously.

By D. G. Collins

As part of its effort to develop ways to maximize resource recovery, the Bureau of Mines investigated the extraction of vanadium from Western phosphate beneficiation tailings with H2S04 and/or H3P04. Dissolution of the vanadium was accomplished by digesting a mixture of acid and a 50-pet-solids, tailings-water slurry. In the most effective method investigated, vanadium and phosphorus were leached by digesting the slurry at a constant boiling temperature (1000-1100 C) in a stirred reactor. In batch tests, maximum vanadium dissolution was 95 pet. In continuous-circuit tests designed to further evaluate vanadium dissolution at con-stant boiling temperature in a continuously stirred reactor, vanadium dissolution ranged from 70 to 85 pet. An economic evaluation of the process demonstrated that H2S04 consumption is the major cost factor. Based on the value of the vanadium product with no allowance for a phos-phate product, the cost of producing the V205 is more than twice its value. The potential for profit would depend upon the value of the phosphate fertilizer produced from the impure H3P04 remaining after vanadium extraction.

Jan 1, 1985

By Y Zhu, W Liang, P Knights

In recent years, Chinese companies have invested billions in Australian mineral exploration, development and processing. In 2008 - 2009 alone, the Foreign Investment Review Board approved $26.4 B of investment. Much of this investment has been by merger and acquisition (M&A) of Australian resources companies. This paper sets out to investigate how Australian CEOs perceive the cultural and institutional challenges in operating Australia mining companies recently acquired by Chinese interests. HofstedeÆs cultural dimensions and institutional theory from management science were used to develop a structured questionnaire, which was subsequently used to conduct telephone interview of the CEOs of six recently acquired mining companies. Analysis of the survey results indicated that, in all cases, few changes were made to the operational management of the Australian companies post-M&A. The three major benefits for Australian companies as a result of the M&A are the ability to; access long-term debt at lower cost; secure finance for growth plans in financially volatile times; and maintain existing management structures. Some perceived negatives involved longer and more convoluted decision-making as a result of Chinese state approval required for investment decisions. The study identified building æGuanxiÆ and an aversion to losing æfaceÆ as important cultural learnings for Australian CEOs. Maintaining effective communications is regarded as key for successful cultural integration.CITATION:Liang, W, Zhu, Y and Knights, P, 2012. Cultural challenges in Chinese/Australian mining mergers and acquisitions - A CEOÆs perspective, in Proceedings International Mine Management 2012, pp 251-260 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By James W. Townsend

The Vicksburg mining property lies in the southeastern foothills of the Star mining district, Beaver County, Utah (fig. 1). Within a few miles of the Vicksburg mine, lying in a semicircle from south to northwest, are such past producers of lead-silver ores as the Moscow, Hoosier Boy, Red Warrior, Wild. Bill, Harrington-Hickory, and many others. Farther to the north, in the San Francisco district, are the famous Horn Silver and Cactus mines. The formation at the Vicksburg property consists of interbedded limestone, shale, and dolomitic limestone. These beds have been metamorphosed by the intrusion of irregular masses of porphyritic igneous rocks grading from quartz-monzonite to granodiorite. Ore deposition is in north-trending fissures of sheeted zones, contact metamorphic in type. These depositions were subsequently altered to gossan. A preliminary investigation of the Vicksburg property involving surveying, mapping, and sampling was made by W. A. Young and F. H. Gunnell, engineers of the Bureau of Mines, in the fall of 1946. As a result of the investigation, a project was set up to investigate the possibility of ore occurrence at greater depth on the fissures under the mineralized zone by diamond drilling.

Jan 1, 1950

By H. Hamza

Efficient and effective management of extraction process tailings is an essential ingredient for the continued success and development of Alberta's vast oil sands resources. Open-pit oil sands operations north of Fort McMurray recover bitumen from flotation circuits. Process tailings are managed in carefully engineered and monitored external tailings management facilities and in below-grade mine pits. In order to support reduction of production costs and improve upon established tailings management practices, CANMET has been working with the oil sands industry in a collaborative framework to assess the potential to integrate thickened tailings into oil sands extraction process flowsheets. Albian Sands has commercialized the process while others, including Syncrude Canada Ltd., continue to evaluate the suitability of the process for their operations. This paper provides an update on R&D work undertaken in recent years to assess and develop the potential of thickened tailings technology for the open-pit oil sands operators of northern Alberta. The aim of this work was to explore opportunities to optimize process efficiency and environmental sustainability by improving water and energy conservation and develop more alternatives for tailings management and reclamation.

Jan 1, 2004

By B Ellis

Brunswick Mine is one of the largest underground zinc/lead mines in Canada, producing 3.4 million tones of ore annually. As mining activities advance to deeper levels, ground pressure also becomes greater. To cope with the highly stressed ground, the mine has taken some strategic measures to ensure the targeted production level. Such measures include the implementation of a pastefill system and transferring the mining method from primary/secondary stoping to pillarless pyramid stoping. With the pillarless mining method, stope sizes become smaller and the number of active stopes is also less than before. In addition, mining sequence and cycle time have to be strictly followed according to production schedule. The blasting project described in this paper tackles one of the steps in the mining cycle aimed at shortening the blasting cycle time in a stope. Furthermore, this project was conducted and managed with the Six Sigma initiative in Noranda which was implemented in the fall of 1999. Like a typical process review, the blasting operation was examined by breaking it down into many steps that can be quantified and measured. Each activity was then correlated with different factors associated with blast design as well as blast operations underground. It was found that the utilisation of voids plays a key role in the blasting cycle time. With improved void utilisation ratio, blasting cycle time has been reduced from an average of 12 shifts to ten shifts per stope. This improvement translates into approximately 180 000 tonnes of ore being blasted without any increase in manpower. This paper presents the technical aspects of the study, as well as some operational issues and improvements made during the project.

Jan 1, 2001

By B. M. McKay

The Walnut Creek Mine was developed in 1989 to supply lignite to the Texas-New Mexico Power TNP-ONE power plant. Being new, we had the opportunity to start from scratch and rethink many of the traditional methods of managing a mine operation. We had the opportunity to create a team environment, encouraging people to get involved and make decisions. The founding philosophy of the mine, "A Quality Product by Quality People", acknowledged that the key to a productive, quality operation was the people. This paper will explore methods employed by Walnut Creek in selection of team members, building the team and the relative success of these methods.

Jan 1, 1993

By A. C. Johnson, es Hol, E. O. Binyon

"INTRODUCTION AND SUMMARYThe tungsten properties of Lincoln Mines, Inc., and North Tem Flute Mining and Development Co. were first explored by the Bureau of Mines in 1942. Work on the project comprised trenching, sampling, a small amount of road and trail construction, and a small amount of core drilling. From April 13 to December 10, 1944, additional diamond drilling was done by the Bureau of Mines to test the lateral and downward extensions of the various tactite zones along the contact south of the Lincoln mine, including the property of the North Tem Piute Mining & Development Co.Claims leased by the Lincoln Mines, Inc., are in secs. 25 and 36, T. 3 S., R. 56 E.; secs. 30 and 31, T. 3 S., R. 57 E.: and sec. 1, T. 4 S., R 56 E., M. D. B. & M., in the Tem Piute Mining District, near the north end of the Timpahute Range in west central Lincoln County, Nev. D. B. Fegles is president of Lincoln Mines, Inc. and general offices are in the Wesley Temple Building, Minneapolis, Minn.In June 1945, the Atolia Mining Co. leased the property and purchased the mill and mining equipment from Lincoln Mines, Inc. P. R. Bradley is president of the Atolia Mining Co., whose offices are in the Crocker Building, San Francisco, Calif. This company surrendered the lease on the property on September 30, 1948. The property owners are continuing operations and are now engaged in building a 20-ton mill.The claims of the North Tern Flute Mining & Development Cc. are in sec. 1, T. 4 S., R. 56 E., M. D. B. & M. Merle F. Schofield is president of the company and maintains an office at Hike, Nev. These claims were leased by H. P. Laslett, of the Utah Nevada Mining Co., in 1945 and by the Atolia Mining Co. in 1946. The owners are now doing some exploratory work."

Jan 1, 1950

By Trevor R. Ellis

"The valuation of mineral properties in the U.S. is only partially regulated. The regulations which have jurisdiction or impact appear to have such mainly as a consequence of unintended fallout, since the regulations were designed for other purposes. Court case history can also be important. The combined results are a mixture of bad and good, with important lessons to be learned.Since 1981, the Securities and Exchange Commission has prohibited U.S. listed companies from reporting quantitative estimates of mineralization and the value of mineralization, other than proven and probable reserves. This results in the minerals appraiser (valuator) working with a shortage of data in his everyday work, both on the subject property and in sales analysis.Between 1989 and 1995, all 50 states and essentially all Federal agencies adopted the Uniform Standards of Professional Appraisal Practice (USPAP) for real property appraisals (valuations). The major national appraisal societies also require their members to abide by USPAP. A significant portion of minerals appraisals must now follow these standards. This paper will discuss the content of USPAP. It provides a very good framework for the valuation of a minerals property or a mine, both as real property and as a business. However, the credentialing standards for real property appraisers are now prohibitive for minerals appraisers."

Jan 1, 2003

By A. B. Parsons

DOWN in Washington an army of individuals constituting the government of a so-called "'democratic" nation is trying to manage the conduct, in its rnultifold phases, of the greatest war in history for the country that is potentially, at least, the strongest in the world and on which, consequently, the major responsibility rests. The enterprise is one of unprecedented magnitude and complexity. That individuals and groups have made and are making serious blunders, both as to the establishment and execution of policy, is to be expected.

Jan 1, 1942

By M. O. Magnuson

This publication describes abandoned-mine fire-control work administered by the Bureau of Mines under cooperative agreements with State and local governments. The work was done by private contractors under the supervision of Bureau engineers. The work is authorized by Public Law 738, approved August 31, 1954, and Public Law 89-4, approved March 9, 1965. Earlier work was authorized by Interior Department Appropriations Acts for fiscal years 1949-55. A total of 70 fires have been controlled under this program in the eastern bituminous region. The nature and extent of the abandoned-mine fire problem in the bituminous region is discussed, and the methods used for controlling these fires are described. The methods that have been used, either singly or in combination, include loading out and cooling the burning material, installing fire barriers, surface sealing, and water and pneumatic flushing.

Jan 1, 1974

By Christopher Mark

After the United States and Australia, South Africa has the largest. modern underground coal mining industry in the world. Historically, South Africa has been the cradle of many innovations in ground control, particularly in the area of pillar design. Today, South African mines are grappling with many of the same issues faced by their U.S. counterparts, including safety during pillar retreat operations, selecting the proper roof support, and maintaining long-term pillar stability. The author recently visited seven underground mines in the Mpumalanga, Free State, and KwaZulu-Natal provinces. Mining methods included longwall, room-and-pillar with continuous miners, and drill-and-blast. The mines represented a cross-section of geology and ground support practices. At each mine evaluations were made of the Coal Mine Roof Rating (CMRR), roof support practices, pillar design methods, and general ground control experience. The coal seams observed were generally thick (2-5 m), the depths of cover moderate (less than 200 m), and the roof rocks relatively strong (CMRR greater than 45). Unfortunately, the South African roof fall fatality rate is approximately three times greater than in U.S., perhaps in part because roof bolts seem to be more widely spaced in most South African mines. Roof bolting equipment was generally outdated, and the quality of bolt installation was a major concern. Pillar design, on the other hand, is quite advanced, and pillar failures are rare. Several novel partial pillaring techniques are employed, including "checkerboard" mining in which every other pillar is removed, 3-cut systems, and high-extraction mining where engineered final stumps are left by design. The paper also offers observations on ground control management techniques (including recently introduced Codes of Practice), the role of the mine inspectorate, and the status of the research community.

Jan 1, 1999

By Theodore Kootz

Manufacture of high-grade ferromanganese; as a rule; requires a low-phosphorus-manganese ore with 45 to 55 percent Mn, chiefly obtained in the Soviet Union, the British Dominions, and Brazil. Also, low-manganese ores have already been used for ferromanganese production, especially in North America .and Germany. During World War I, a process was developed in which a high-phosphorus ferromanganese or spiegeleisen was prepared in the blast furnace from law- or high-phosphorus manganiferous ores, then low-phosphorus manganese slag was prepared by refining under an acid slag, and this material was, worked into a low-phosphorus ferromanganese in the blast furnace.9/ Manufacture of useful manganese ores from a phosphorus-bearing spiegel with 12 to. 15 percent Mn, 4.5 percent C,, and 0.5 percent P by slagging in a refining furnace was reported by Joseph, Barrett, and Wood.10/ The spiegel was refined to 0.75 percent Mn, 3.4 percent C, and 0.45 percent P. Thereby, a slag with about 43 to 58 percent Mn and, about 10 percent Si02, was obtained. Hotter melts gave a smaller phosphorus content in the slag than cold melts. In addition, the phosphorus content of the slag varied with the manganese content of the intermediate metal.

Jan 1, 1952

By O.W. Ellis

Recently there has been a considerable revival of interest in the effects of the various elements commonly added to brass for the purpose of increasing its strength. For many years the work of Guillet2 alone gave reliable information in this regard. Even today his determinations of the coefficients of equivalence of the various elements relative to zinc in brass are those universally employed in industry. This is so because these coefficients have stood the test of time—their substantial correctness has been proved in almost universal practice. It is not our intention to discuss here these coefficients or their use. Rather do we wish to emphasize the need for further systernatic studies of the mechanical properties of the ternary systems of copper, zinc, and other individual elements. Since Guillet published the results of his first investigations Millington, 16 Smalley33 and Thiband 45 have added somewhat to our information. In general they have confirmed the findings of Guillet, which may be stated in the following rather general terms: 1. The addition of aluminum to the 70:30 and 60:40 brasses progressively increases their hardness and strength and reduces their ductility and resistance to shock. 2. The addition of small amounts of iron to a 60:40 brass improves its strength without affecting its ductility. 3. The addition of small amounts of manganese to a 60:40 brass causes a progressive increase in its strength and reduction in its ductility. A considerable amount of information has been amassed in regard to the effect of nickel on brass (9, 22, 41) which it is unnecessary to refer to here, in view of the scope of this paper. The situation in regard to these alloys in 1926 was very clearly stated by an anonymous writer,47 in The Metallurgist of February of that year, whose remarks were so to the point that they are well worth quoting: It will he seen that there are still large fields remaining to be studied in each of these systems (those of the aluminum, iron, nickel and manganese brasses) before our knowledge is adequate. When we come to the more complicated systems the position is even less satisfactory, and on account of the very incomplete nature of the work which has been

Jan 1, 1929

By O. W. Ellis

Recently there has been a considerable revival of interest in the effects of the various elements commonly added to brass for the purpose of increasing its strength. For many years the work of Guillet2 alone gave reliable information in this regard. Even today his determinations of the coefficients of equivalence of the various elements relative to zinc in brass are those universally employed in industry. This is so because these coefficients have stood the test of time—their substantial correctness has been proved in almost universal practice. It is not our intention to discuss here these coefficients or their use. Rather do we wish to emphasize the need for further systernatic studies of the mechanical properties of the ternary systems of copper, zinc, and other individual elements. Since Guillet published the results of his first investigations Millington, 16 Smalley33 and Thiband 45 have added somewhat to our information. In general they have confirmed the findings of Guillet, which may be stated in the following rather general terms: 1. The addition of aluminum to the 70:30 and 60:40 brasses progressively increases their hardness and strength and reduces their ductility and resistance to shock. 2. The addition of small amounts of iron to a 60:40 brass improves its strength without affecting its ductility. 3. The addition of small amounts of manganese to a 60:40 brass causes a progressive increase in its strength and reduction in its ductility. A considerable amount of information has been amassed in regard to the effect of nickel on brass (9, 22, 41) which it is unnecessary to refer to here, in view of the scope of this paper. The situation in regard to these alloys in 1926 was very clearly stated by an anonymous writer,47 in The Metallurgist of February of that year, whose remarks were so to the point that they are well worth quoting: It will he seen that there are still large fields remaining to be studied in each of these systems (those of the aluminum, iron, nickel and manganese brasses) before our knowledge is adequate. When we come to the more complicated systems the position is even less satisfactory, and on account of the very incomplete nature of the work which has been

Jan 1, 1929

By V. A. Zhilina, I. V. Shadrunova, O. E. Gorlova

"The aim of the study is to develop and scientifically justify a new adaptive approach to the separating processes of deep and complex processing technogenic mineral raw materials. Technogenic mineral resources as a waste of mining and processing industry are mostly complex objects that have specific features of material composition and technological properties and make it processing ineffective with traditional schemes of mineral raw materials enrichment. Mineral wastes are regarded in this study as a complex object with a large number of signs in conditions of uncertain environment and object. However, adaptation is regarded as the process management system’ adaptation to the specific the properties of the object and the environment that has several hierarchical levels corresponding to different stages in the management of complex object. An adaptive approach is considered as a methodological basis of multivariate schemes for opening the mineral resources and creating mechanisms that could transfer these potential technogenic resources to the actual that significantly expand the mineral resource base of the country's black, coloured, rare, noble metals and construction materials. In this case, potentially the solution to the most pressing social and environmental problems associated with the adverse effects of past economic activity simultaneously with the commercial objectives. This approach to the wastes mining and related processing manufacturers meets the core idea of sustainable development as the balance of interests of State, society, business, private enterprise and each person in the areas of rational use of resources, economic efficiency and environmental safety. On the example of metal-containing raw materials in the form of slags of ferrous and nonferrous metallurgy, ferrous metallurgy sludge, mature fine tailings, the application of adaptive approach illustrates to the development of technologies of its deep and complex processing as phased, thoughtful movement from a comprehensive study of technogenic raw materials to build optimal topologies of technological schemes for processing the mineral wastes. INTRODUCTION Involving the Russian economy in the system of global economic relations significantly changes the nature of the country's competitiveness in the development of the world market and urgently requires competent management of its own natural and mineral resources. The latter at the present time in real economic processes cease to be a passive material foundation and become the producing basis in the production processes in the status of so-called natural capital. Introduced in the field of economic theory at the end of the 20th century, this term means both the flow of natural services and real natural resources. Consequently, natural objects, which act as natural resources of a certain production, today must necessarily be evaluated in a strategic sense. Modern standards of sustainable development presuppose that the economy should equally be oriented to balance the interests of the state, society, business, individual enterprise and each person in the spheres of rational use of resources, preservation of healthy ecosystems, ensuring well-being, high quality of life and environmental safety of not only the current generation, but also respect for the rights of future generations, that is, intergenerational equality. Most types of minerals are classified as non-renewable resources, therefore resource-saving in the sphere of mineral and raw materials complexes is one of the most important factors-indicators characterizing the degree of approximation to the model of rational subsoil use, and, consequently, sustainable development (State Report, 2017)."

Jan 1, 2018

By T. Chikande

"Falls of ground pose costly hazards to personnel and equipment and thus measures should be taken to prevent them. This study endeavours to improve the support systems used in geotechnically poor ground at a Zimbabwean platinum mine by analysing the status quo and recommending an effective support system. Various techniques were used to determine the quality of ground conditions, predict the rock mass behaviour, and to identify the appropriate rockbolt type. An analysis of the current ground control methods and their limitations was also undertaken.The results showed that the current support system and mining practices in poor ground need to be modified to improve safety and productivity. Stoping overbreak is influenced by poor ground conditions and the explosives currently used. The use of emulsion is recommended to replace ANFO. Redesigning of pillars is also recommended in poor ground conditions. An evaluation of the current roofbolt system indicated an opportunity for improvement. With new insight on the performance of the shorter length roofbolts currently in use, a new support system was recommended taking into consideration cost-benefit analysis. Barring down using pinch bars in poor ground was seen as a risky and time-consuming exercise, hence the use of mechanical scalers is recommended to achieve zero harm and to meet production targets. Smoothwall blasting is recommended in poor ground to minimize excavation damage. Other recommendations include the use of hydrological surveys to determine groundwater levels and implement corrective measures. Both empirical and numerical modelling approaches need to be utilized in determining the optimum support. IntroductionThe presence of geological discontinuities such as faults and joints weakens the rock mass. Adequate support is critical in achieving zero harm in underground mines. This paper reviews the current support systems used in poor ground conditions at a Zimbabwean platinum mine. The area of research is located on the Great Dyke of Zimbabwe. The mine exploits platinum group elements (PGEs) and base metals. It is shallow, having a maximum depth of less than 300 m. The Great Dyke is the second largest reserve of PGEs, following the South African Bushveld Complex (Oberthur et al., 2012). It is a linear layered intrusion that extends for about 550 km with a maximum width of 11 km (Prendergast, 1989). The generalized section of the Great Dyke is almost like a trumpet, comprising layers that dip towards the centre. The reef exploited at the mine, the Mineralised Sulphide Zone (MSZ), is located in the pyroxenite layer, which is hosted in the ultramafic sequence. The MSZ is a uniform layer about 2– 3.5 m thick, dipping at around 10–14° from surface outcrop towards the axis of the basin, and located between bronzite and websterite horizons. The visible disseminated sulphide mineralization shows a typical and consistent vertical distribution of platinum group metal (PGM) and base metal values. The research was undertaken to review the current support systems used in geotechnically poor ground conditions in a bid to improve both safety and productivity."

Jan 1, 2016

By Gunnar Thaning, Borje Bjorkvall

At LKAB Central Division for Metallurgical Research at Malmberget, Sweden, fired pellets are examined in respect to mechanical and reduction properties. The paper deals with descriptions of the test methods. It also involves the rationale for the choice of these tests. Their correlation to the blast furnace operation will be examined. The mechanical tests used are the ISO-tumbler test and the cold compression strength test. Concerning the metallurgical properties, experiments have shown that some superbasic pellets in particular have different disintegration properties in different temperature ranges. Pellets which have favorable reduction properties when tested under isothermal reduction at high temperature may disintegrate to a large extent under low temperature reduction. This is also valid for some types of acid pellets. Consequently, it was found to be necessary to determine the reduction strength both at high and low temperatures. In the low temperature range, the disintegration is measured by tumbling the pellets in soft reducing conditions at 600°C in a modified Linder test equipment. The high temperature reduction strength is determined under load in the Burghardt-Grebe equipment. However, in order to get more information of the high temperature strength, LKAB intends to introduce a softening test. The tendency of high temperature disintegration will also turn up in the swelling test. The swelling properties are examined according to a procedure developed at LKAB. In this test the pellets are subjected to free swelling without mutual contact. The reducibility of the pellets is recorded in the swelling test.

Jan 1, 1974

By R. A. Spitz, R. Leiby, M. Bricker

Electrochemistry plays a significant role in minimizing wastes at East Penn's secondary lead smelter. East Penn has been recovering spent battery acid for reuse in new batteries since 1992. East Penn also produces a fertilizer feedstock from sulfur dioxide in the smelter stack gases. The success of these processes is, in large part, due to the installation of electrochemical cells. The cells in the acid recovery plant allow the waste from this process to be concentrated into less that 10% of the original spent acid. The cells in the fertilizer plant treat the solution to remove dissolved metals prior to sale to fertilizer manufacturers.

Jan 1, 2000