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By M. Steyn

[Zr(C9H6NO)4]?(HCON(CH3)2)?(H2O), where (C9H6NO) = 8-hydroxy quinoline (oxH), was synthesized and characterized. This tetrakis-coordinated zirconium complex crystallized in the triclinic crystal system (Pi, Z=2) along with water and N,N?-dimethylformamide(DMF) solvate in the asymmetric unit. The metal atom is surrounded by four N,O-donating bidentate ox-ligands that are arranged around the metal centre to give a square antiprismatic coordination polyhedron with a small distortion towards a dodecahedral geometry. Crystal packing is stabilized by intermolecular interactions of adjacent oxine ring systems in neighbouring molecules, as well as hydrogen bonding of the aqua and DMF solvate molecules, linking the molecular entities into a supramolecular three-dimensional network.

Jan 1, 2013

By J. W. Joubert, R. C. W. Webber-Youngman, M. D. Budeba

"SynopsisCost estimation for surface coal mines is a critical practice that affects both profitability and competitiveness. New mines require these costs to be estimated using available information before a project begins. The competitive advantage of a new mine depends on it being both efficient and cost-effective. Low-cost producing mines have a higher chance of survival in a low-price environment than do high-cost producers. The competitiveness and profitability of a coal mine is based on the costs of production and the supply position on the cost curve. There is no single method of cost estimation, and the available methods consider only one or a few variables, leaving out multiple variables that could significantly affect the estimation of mine costs. Mining companies are thus searching extensively for a method that will increase accuracy in the estimation and evaluation of mining projectsThis paper highlights the shortcomings of the available approaches and proposes a data envelopment analysis method to develop a frontier for effective surface coal mines, and the use of a parametric method for modelling the costs and productivity of new mines to ensure effective competitiveness. The models will extend the capability of estimation and the accuracy of estimates using the efficient decision-making units, by considering the optimal mine-specific and external variables affecting costs.IntroductionCoal contributes 25% of the world’s primary energy needs, after fuel oil, which contributes 35%. The world energy demand, estimated over the period 1990 to 2030, is expanding at a cumulative annual growth rate (CAGR) of 1.7% (Schernikau, 2010, p. 14). This emphasizes the need for enhancing the production of existing mines, as well as opening new mines in order to increase the supply of coal."

Jan 1, 2015

The two candidates in the upcoming presidential election in the United States each say that they have their own solution to the nation?s energy problems - solutions that will increase the amount of energy available, lessen the nation?s dependence on foreign sources and reduce the amount of pollution released to the atmosphere. Democratic nominee Sen. Barack Obama and Republican candidate Sen. John McCain both advocate research funding for coal-to-liquids and clean coal technologies. McCain also supports increased oil and gas drilling offshore. And Obama has even made some noises in that direction, although his plan leans heavily on the increased use of renewable energy sources. The energy debate is not new to this election. Congress and whichever party is in the White House has for years been trying to craft a comprehensive energy policy. One difference in this latest debate is that the increased use of nuclear energy has gained more attention. Current President George W. Bush has said he favors the increased use of nuclear power as part of the nation?s energy package. And McCain said he supports the building of more nuclear power plants. Obama has not said much about that. The American public is also showing signs of changing its stance on nuclear energy. To be sure, images of Three Mile Island and Chernobyl are still alive in some minds. However, the American public has said it wants cheaper energy and they want it produced more cleanly. With nuclear, the nation can have both. In the United States, nuclear accounts for slightly less than 20 percent of the electrical power used (see interview with Gary Steele of Energy Fuels on page 27). Globally, that figure is about 15 percent. And there are several nations that derive better than half of their power from nuclear sources. Add to that the world?s increasing need for more energy and the future of nuclear is bright.

Jan 1, 2008

By G. S. Hill, B. J. Huls

This paper on coarse particle recovery (CPR) summarizes a process to capture coarse particles that are not recoverable by regular flotation. Several porphyry copper operations in the world operate analogous circuits that recover non-floated copper from tailings; however, the case presented here is unique in that extensive underlying test work has allowed the authors to elucidate some fundamental principles behind recovery enhancement. This paper discusses an overview of the flowsheet that is proposed to Minera Escondida Ltda., the nature of copper in the feed to the CPR circuit, and the various unit operations within the recovery circuit.

Jan 1, 2006

By Mohamed A. Younis, Paul J. Headland, Paul H. Madsen, Vojtech Gall

INTRODUCTION A 100 ft long, 20 ft high and 18 ft wide NATM tunnel was excavated through grouted clean sands beneath a busy city street, including a variety of existing utility lines. The new tunnel associated with a hospital expansion will serve as a pedestrian tunnel connecting a parking structure with a new hospital facility. Tunnel construction started on December 15, 2005 when drilling for the grouting program started and was completed on May 26, 2006 when the tunnel final lining was completed. The tunnel was constructed by Kiewit Construction Company as a tunnel subcontractor to The Christman Company who is constructing the hospital facility for Spectrum Health in Grand Rapids, Michigan. URS was the project designer. GallZeidler Consultants, LLC were the contractor’s NATM consultant. PROJECT DESCRIPTION The Michigan Street Pedestrian Tunnel is a component of the Michigan Street Development located along the north side of Michigan Street NE between Coit Avenue NE and North Division Avenue in the downtown area of the Grand Rapids, Michigan. The Michigan Street Development includes a parking deck and four new towers to be constructed over the proposed parking deck. The tower planned furthest east is being developed by Spectrum Health as the Lemmen-Holton Cancer Pavillion. The purpose of the pedestrian tunnel is to connect the proposed Lemmen-Holton Cancer Pavillion with the future Spectrum building to be located on the south side of Michigan Street NE. The southern end of the tunnel was constructed with a bulkhead until the future Spectrum building is constructed at which time interconnection will be required. The tunnel site plan and profile are shown in Figure 1, Site Plan, and Figure 2, Tunnel Profile. Several challenges were faced during the design and construction of the Michigan Street Pedestrian Tunnel. These challenges included compressed design and construction schedule, maintenance of traffic and protection of old underground utilities. The tunnel was being constructed as part of the Michigan Street Development and coordination with other concurrent construction activities was required. The tunnel was constructed within a specified window of time to allow other associated construction activities to take place without compromising the overall project schedule. The design started in June 2005 and construction was completed by June 2006.

Jan 1, 2007

IF a straight line should be drawn on the map (See 1, page 96) through the northern half of the South Island of New Zealand, from Mt. Domett in the north to Arthur's Pass in the south, and another line drawn parallel to it and at a distance of ten miles to the west, according to the topographic scale, it will be found that within the belt thus drawn across the country all the most important mines, past and present, of the South Island are situated, with the exception of a few in Otago.The most important product of this tract being gold, and Reefton, the most important southern mining field, being situated at about its central portion, the zone may aptly be termed "The Great Reefton Gold Belt." The occurrence of so many gold mines along this particular strip of country is not at all a matter of chance, but is the outcome of cause and effect. Running along the eastern side of the gold belt are the Brunner and Victoria Ranges, which are chiefly composed of crystalline schists and metamorphic granite of probably Cambrian or Silurian age; between these and the gold-bearing series there are interposed at one or two places some beds of slates, limestones, and...

Jan 1, 1910

By B Orchard

New Zealand SteelÆs Waikato North Head mine, situated at the mouth of the Waikato River, supplies approximately 1.2 million tonnes per annum of titanomagnetite concentrate to the Glenbrook steel mill. The mine draws its fresh water supply from the Waikato River, abstracting approximately 38 000 cubic metres per day. During the concentration process of the ironsand, slimes are liberated into the plant wastewater. The plant wastewater, storm water and groundwater from the mining operation is treated and passed through settling ponds. Around 118 400 cubic metres per day of water are drawn from the recycle settling ponds for use in the concentration plant. Typically a daily average of up to 15 100 cubic metres of the treated water is discharged back to the Waikato River. Since the early 1990s significant improvements have been made to the water treatment at Waikato North Head mine and regularly the mine discharge water quality is similar or better than background river water quality.

Jan 1, 2002

Present roof bolting practices in the collieries of Australian Iron and Steel Pty. Ltd. are outlined. Roof support has been improved since introducing roof bolts and it is hoped to increase the reliability of the bolts still further.Expansion-shell, and split and wedge roof bolts five to eight feet long are placed by "Atlas Falcon" and "Fletcher" roof bolters. Both anchorage and tightening have presented some problems.Good panel supervision is required if systematic roof bolting is to be properly co-ordinated with coal production without unnecessary delay to either. Successful roof bolting can only be the product of conscientious men and supervisors who are all convinced of its value. A rigid operational code should be established early and maintained.INTRODUCTIONRoof bolting is a method of support which is permanent and reduces or eliminates the need for other support; The method was pioneered in America and was first experimentally investigated in Australian collieries at Elrington in 1949 (McKensey, 1953). Pneumatic installation methods were employed. Subsequently, a method of using standard hand-held electric coal drills was developed at John Darling Colliery (Horseman, 1954). Pneumatic roof bolting equipment was first operated in the collieries of Australian Ironand Steel Pty. Ltd (A.I. &. S.) in 1951. Since then various hydraulically operated mobile machines have been installed in Australian collieries and these, together with improved pneumatic equipment, form the two present basic methods of placing ,roof bolts. Roof bolt anchorage is achieved by either split and wedge or expansion-shell bolts.The two broad types of roof bolting are 1. consolidation of strata, and 2. suspension support.

Jan 1, 1961

By Warren Howes, A. B. Campbell, W. H. Ode

"INTRODUCTION The mines in the eastern part of the now active region of the Tri-State zinc district of Missouri, Kansas, and Oklahoma have unusually acid water, which during periods of moderate or no rainfall is used in the mills to replace losses from evaporation, seepage, and tailings disposal. Its use has caused difficulties by corrosion of equipment and by interference with flotation.The growing importance of flotation, which requires good water, and the increasing troubles caused by the corrosion of the milling equipment have prompted the Mississippi Valley Experiment Station of the United States Bureau of Mines, in cooperation with the Missouri School of Mines and Metallurgy, Rolla, Mo., to investigate the action of the waters on flotation and to undertake to develop means of obviating their harmful effects.The work was under the immediate direction of W. T. Schrenk, consulting chemist, United States Bureau of Mines, and professor of chemistry, Missouri School of Mines and Metallurgy, and Will H. Coghill, supervising engineer of the ore dressing section of the United States Bureau of Mines.ORIGIN OF ACID MINE WATERSRain water, carrying oxygen and carbon dioxide in solution, finds its way into the pores and crevices of the earth's crust and percolates downward through the rocks. This water and its dissolved gases exert a solvent action on many minerals, the extent of which depends upon the nature of the associated minerals.The iron sulphides are the chief sources of the 'trouble with sulphates and sulphuric acid because they oxidize so freely and contain more sulphur than is required to satisfy the iron when ferrous sulphate is formed. Galena and sphalerite may oxidize to sulphates without liberating acid. A few of the common reactions occurring in the Tri-State mine waters may be illustrated by the following equations:"

Mar 1, 1932

The risk associated with mining induced seismicity is one of the major threats to the safety and sustainability of deep underground mines. This paper describes techniques that allow site practitioners to efficiently control such risks in mines. The proposed approaches rely on ground support to strategically control seismic risk and re-entry time to tactically control this risk. The strategic approach is based on the detailed understanding of past seismicity to as certain the seismic hazard of individual sources throughout the mine. This approach also relies on assessing the potential damage that these sources can induce on nearby excavations using the excavation vulnerability potential (EVP) and rockburst damage potential (RDP) concepts proposed by Heal et al. (2006). It is then possible to investigate how to reduce the risk of experiencing damaging seismicity in mine drives by locally enhancing the ground support system. The tactical approach relies on a proposed methodology to estimate reliable re-entry times or exclusion periods based on the seismic decay following blasting. Some examples of how these techniques have been applied in Australian mines are given.

Jan 1, 2009

By K C. Williams, A W. Roberts, J D. Prigge

For stockpile design, the flowability and structural interfaces are critically dependant on the stress conditions throughout the pile. Historically, the predictive methodologies for stress determination have been too conservative, which adds inefficiency to the stockpile reclaim interface selections, especially for live reclaim stockpile systems. In addition, accurate pressure profiling throughout stockpile is essential to correctly design the stockpile support structures, which are buried within the stockpile. Such buried structures include trestle legs or columns to support load-out conveyors or the roof of bulk storage sheds. Improved methodologies with respect to the development of the hoop stress condition which exists in material ædrawn-downÆ within the stockpile has been developed. This hoop stress approach has significantly improved the live capacity prediction to over 90 per cent accuracy and improved rathole structure prediction within live reclaim stockpiles. Additionally the methodologies in estimating the vertical and circumferential stress variation acting on buried stockpile structures have been significantly progressed, with experimental testing shown good agreement with the theory.CITATION:Williams, K C, Roberts, A W and Prigge, J D, 2013. Recent developments in stress analysis and live reclaim prediction within iron ore stockpiles, in Proceedings Iron Ore 2013 , pp 501-510 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By R. G. Fleck, W. R. Webb

Iron ore mining in the Adirondack region of northern New York dates back to the Revolutionary War. It is recorded that Benedict Arnold in his campaigns in the Lake Champlain area during the American Revolution utilized the local ores to produce armament and cannon balls. Through the efforts of early pioneers, the iron mining industry in northern New York gained impetus so that in the 1880's mines in the area accounted for nearly one fourth of the iron ore produced in the United States. Both magnetite and red hematite ores were mined during this period. With the discovery of the Lake Superior ores, the iron ore industry in New York started to decline and remained relatively unimportant until 1938. Modern day methods of mining and beneficiating sufficiently high tonnages of low-grade ores to justify the large expenditures for plant and equipment prompted a resurgence in northern New York mining. During the past several years, the production of iron ore from the Adirondack magnetites has greatly increased, and production which amounted to .6%, of the United States total during the 1918-1928 period (Mining and Metallurgy, November 1943) has been increased to 2.85% of the total in 1948. Today, Republic Steel is mining in the Port Henry-Mineville and Lyon Mountain areas; the

Jan 4, 1950

By G. L. Smith

This paper consolidates the key elements of seven contributions, on strategic long-term planning, to two of the three international conferences on Strategic versus Tactical approaches in Mining held over the period 2005?2008. The holistic concept of strategic long-term planning as developed and implemented at Anglo Platinum is described. Consideration is given to the planning cycle, principles supporting the construction of the long-term plan, and aspects of unique best practice as developed in Anglo Platinum. Further description of Anglo Platinum?s approach to corporate governance, including the processes, methodology, systems, unique tools and techniques that are applied to value and select capital investment options is also given.

Jan 1, 2009

By Edward Keller

The work covered by this report was undertaken at the request of Dr. J. A. Holmes, late Director of the Bureau of Mines, to whom the writer had been recommended by C. W. Goodale and E. P. Mathewson, of Butte and Anaconda, Mont. The director's offer was accepted for the honor it conferred and for the useful results that might be promulgated by the work in the technical field covered. The investigation was facilitated by permission to visit various works and sometimes by contributions of important definite information on a given subject. It is therefore with pleasure that acknowledgment of courtesies is made to the following corporations and gentlemen: Anaconda Copper Mining Co., Raritan Copper Works, Baltimore Copper Smelting & Rolling Co., United States Refining Co., American Smelting &, Refining Co., B. B. Thayer, A. C. Clark, A. L. Walker, William H. Peirce, E. A. Cappelen Smith, H. H. Alexander, F. C. Newton, S. Rolle, R. W. Deacon, N. W. Pierce, O. C. Martin, C. N. Sappington, James K. Thomson, W. G. Derby, and the assistants of the writer, K. W. McComas and W. L. Raup. In this report considerable space has been devoted to general and theoretical principles on the ground that under modern conditions the best results in any field of activity can be attained only with the a. id of an adequate knowledge of the best theories underlying the practice. The diffusion of such knowledge in the field of sampling metallic metallurgical materials appears to have been quite insufficient, and it is felt that when the principles involved are once thoroughly comprehended their universal application will be appreciated, so that it will make no difference whether pig iron or gold bullion is offered for test. It may further be noted that a discussion of the theories underlying practical methods is placed under the caption "Practical Sampling," with the idea that no one can be a practical sampler unless he is capable of analyzing his methods. No attempt has been made to advocate any one method, but it is hoped that the analyses of all of the methods in use will show where each may be correctly and safely applied. The fact that it is possible to demonstrate the theoretical correctness of several methods indicates the invalidity of the claim that any single one of them is the standard.

Jan 1, 1916

By Pat C. Hautala, J. R. Hoskins

This is a new era for the minerals industry. Never before has there been more need for effective communication. So said Robert Anderson, chairman and chief executive officer of Hanna Mining Co. He was speaking to the American Mining Congress's Communication Workshop. The question is whether there is enough industry concern to meet the challenge. Anderson observed that increased workshop attendance, in continuing tough times, reflects the industry's concern for communication. But, why were students, faculty, engineers, supervisors, and managers not at the conference? Communication applies to every manager, Anderson said. But he was the only operating manager present. And only one company sent operating supervisors. The remaining conference participants were public relations personnel, generally with nonmining backgrounds. And the program dealt mostly with public relations issues. Role of Communication in the Minerals Industry. It is well known that the minerals industry faces economic, political, and social problems. Economic shifts and foreign competition have created an international minerals industry and an international marketplace. This, in turn, calls for worldwide communication. Other factors effecting communication are: • Governmental protectionism as well as regulatory reforms call for increased interaction with governing officials. • Changing social values have created environmental issues and anti-industry attitudes. This intensifies the need for improved public relations. • Traditional work values are shifting towards self-actualization and humanistic movements. The work force is better educated and more informed. Employees demand more satisfaction, equality, and job autonomy. • The mining industry's task of managing its human resources is complicated by layoffs, job uncertainties, and bleak outlooks concerning employee morale and motivation. Technology and Information for a New Era As noted, this is a new communications era, one propelled by technology and information. Technology has led to reduced demand for raw materials by developing substitutes. Copper demand, for example, will never fully recover. Copper cables are replaced by fiberoptics; copper transmission lines, with aluminum. Technology has shifted the US from traditional to high tech and service industries. The speed, frequency, and scope of information transmission have greatly increased. But the most significant characteristic of this information is not the pace of advancing technology. It is the dramatic increase in the importance and frequency of our personal transactions. Knowledge has replaced raw materials and capital as the strategic resource. Information has replaced energy as the transforming resource. And the game against nature has become an interpersonal game (D. Bell, Post-industrial society, Physics Today, '76). In Megatrends, John Naisbitt says that information will soon double every 20 months. So, professionals will become "information workers." And communication will be the life channel of the information age. Thomas Wolfe said you can't go home again. Hanna Anderson said we are, indeed, facing a new day. It will never again be "business as usual." We must move into the information age with the rest of society. We cannot trust that the world will continue to rely on our products. Nor can we place the responsibility and control for problems and solutions outside the minerals industry. Improved communication is not a panacea. But, Anderson said, it is critical to the minerals industry. What is Communication? The word communication is overused. It is applied to every aspect of our lives. Satirist Tom Lehrer got sick of hearing about the need to communicate. He said, "It seems to me that if someone is having all that trouble communicating, the very least he can do is shut up!" Obviously, we cannot follow that advice (though we might wish that some others would do so). Communication is always going on. It is inevitable. Yet we have many misconceptions about com-

Jan 1, 1985

By A. V. De Forest

INSPECTION and test methods of great diversity have been used from the most ancient times to select raw material, control its manufacture, and appraise its finished properties and value. The "miller thumb," expert in grading flour, the vintner's sense of taste, the goldsmith's micro-wear test on a touchstone, the enquiring sniff over the doubtful egg -these are all nondestructive inspection methods, accurate and depend- able, but not readily reduced to numbers in the c.g.s. system. A horse trader inspecting a possible purchase is interested in more than age, size, weight, color. heredity, speed, or drawbar pull which can be reduced to figures. Behavior, temperament, stamina, health-past, present and future---are just as important as the numerically determinate constants.

Jan 1, 1940

By D. K. Ingram

In situ horizontal stresses were measured to determine the influences of geologic anomalies on the regional horizontal stress field in two coal mines in southern Illinois. Stress measurements were obtained near a normal fault having a 121-ft displacement at the AMAX Wabash Mine and a large coalbed want at the Kerr-McGee Galatia No.5 Mine. Horizontal stress measurements were completed using a Bureau of Mines borehole deformation gauge. The average maximum and minimum horizontal compressional stresses at the Wabash Mine were 1,400 and 800 psi, with the direction of maximum stress ranging from N 78° W to N 83° E. At the Galatia No.5 Mine, the averages were 1,500 and 500 psi, with the direction of maximum stress ranging from N 85° E to N 75° E. Generally, the geologic anomalies appear to have no dramatic effect of the regional horizontal stresses. However, subtle differences between stress measurements suggest an influence by the fault zone at the Wabash Mine. The larger anisotropic stress conditions at the Galatia No.5 Mine could be responsible for the increase in kink zones and directional roof failures.

Jan 1, 1988

The C.S.A. copper-lead-zinc mine, located 7 miles north of Cobar in central-western New South Wales, is the largest known mineral ocurrence in the Cobar mining field. The generally discordant orebodies occur within a strike width of 600 ft and an overall strike length of 1200 ft. They are enclosed by the steeply westdipping, west-facing sediments of the Cobar Group, and comprise lenticular steeply north-pitching and eastdipping zones of sulphide mineralization which range in composition from massive pyrite-sphalerite-pyrrhotitegalena to less massive pyrite-pyrrhotite-chalcopyrite varieties.The thinly bedded siltstones, shales, and greywackes enclosing the mineralization appear to have derived some of their constituents from volcanic sources. They have been metamorphosed to the greenschist facies of regional metamorphism. At least two stages of deformation and folding have occurred. The first stage folded the rocks on a south pitching fold axis into their present configuration, and superimposed a strong axial plane cleavage which subsequently guided the emplacement of the mineralization. The second stage of deformation is considered to have controlled the zonal distribution of the orebodies.

Jan 1, 1970

By Wilbert J. Huff

[This is the fifth of a series of annual reports of the explosives Division, Bureau of Mines, United States Department of the Interior.3/ It deals particularly with work done during the period July 1, 1939, to June 30, 1939. The writer and the respective unit leader to whom credit is indicated have directed the various studies outlined.]

Jan 1, 1940

By C. E. M. Meskers

Electronic and Electric Equipment contains a range of components made of a wide variation of metals, plastics and other substances. Up to 60 elements can be found in complex electronic equipment: base metals, precious metals and special metals in circuit boards and batteries. Because of its amount WEEE represents a considerable metal resource with a higher special and precious metal content than found in ores. The Umicore integrated smelter and refinery recovers and supplies back to the market 17 different metals from EEE. Pre-treated materials enter state of the art, material and energy efficient metallurgical processes for environmentally sound recovery of metals and treatment of off gasses and hazardous substances. The organics in the feed function as reducing agent and alternative energy source during smelting for precious metal recovery. Lithium-ion batteries are treated using a dedicated process. As a result the environmental footprint of metals produced from EEE is much smaller than primary production.

Jan 1, 2009