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By Chen Bingchen, Ma Shaojian

A new magnetic liner, with unique magnetic circuit and novel structure designs, was developed. It was characterized by light weight, low noise, as well as corrosive and abrasive resistance. The wear rate of the magnetic liner was one twentieth and one ninth those of the manganese-alloy steel and rubber ones respectively. The forming mechanism of the protective layer and that of influencing factors on magnetic liners were also investigated. The research results could not only instruct using magnetic liner, but also widen their application.

Jan 1, 1995

By K. A. Prisbrey

Mineral carbonation is the reaction of carbon dioxide with mineral silicates to form solid, carbonate compounds. The carbonate ion holds carbon in a low energy state – lower than in carbon dioxide. Thus the reaction of carbon dioxide to produce mineral carbonates captures the carbon in a stable, solid form. The University of Utah is investigating the carbonation of silicate minerals by mechanochemical processing, which has the potential of being much less expensive than other methods. Tests to date have shown that a marked change takes place in the lizardite variety of serpentine after 15 to 20 minutes of intense grinding in the presence of gaseous CO2. Further testing is in progress.

Jan 1, 2004

By G. S. P. Pereira, E. M. R. Santos

Acid mine drainage (AMD) is a serious environmental problem in mining activities. Prediction is the first step for evaluate the potential of acid generation and there are some possible methods to estimate it. They are described as static tests, which examine the balance between acid producing and acid consuming materials, and kinetic tests, which attempt to predict drainage quality overtime. Static methods are very simple and give a qualitative classification of the ores based on their potential to generate acid drainage. The characterization of ores to determine their acid producing potential is vital for the prevention of long term environmental liabilities. Laboratory tests were conducted under different methodologies to predict the acid producing potential of sulphide overburden, ore materials and tailings from a deposit of copper ore.

Jan 1, 1999

By K. Valta

This paper presents an approach for developing a Sustainable Development Indicators (SDIs) framework tailored to the Greek Industrial Minerals sector, due to its importance for the national economy. To achieve this goal, an overview of the Greek mining and minerals, and especially the Industrial Minerals sector, from a technological and a financial perspective, is presented. In addition, a brief description of the global initiatives to this direction is given. The proposed indicators are based on those presented in 2006 by the Greek Mining Enterprises Association (GMEA) adjusted for the sector of industrial minerals by taking into account economic, environmental and social issues, known as the Triple Bottom Line (TBL) approach.

Jan 1, 2007

By N. Vayenas

Modern mines possess a wide variety of capital intensive equipment. Equipment failures and the associated down time contribute significantly to the overall maintenance, operating and production costs of a mine. Reliability investigations are becoming a standard practice, as the equipment becomes more complicated and the effective use of resources is critical for achieving higher productivity and mine safety. In view of the recent global initiative for sustainable development in the mineral industries, reliability of capital intensive machinery should be considered as a key indicator for sustainable development and growth. This paper discusses the application of equipment reliability as a sustainability indicator and proposes a methodology for its practical use. Reliability of equipment systems is useful for product life cycle assessment, mine performance measurement and evaluation.

Jan 1, 2007

By John Jonkman

During the decade of the eighties, the mining industry was able to take advantage of numerous advancements in computing technology. The development of the desktop workstation and the tremendous increase in power of minicomputers have cause many of the technical computing applications to be taken out of the "glass house", or central computing facility, and distributed to where the work is actually performed. This trend, combined with the significant price/performance improvement being experienced, has resulted in computers becoming more readily available at a reasonable cost for research and development activities, thus increasing the amount of new development taking place. The papers in this session discuss research and development work which has resulted in advancements in mining technology applications in the following areas: - Technical Parameterization - Linear Programming - Dynamic Programming - Computer Aided Design

Jan 1, 1989

By Z. Stanojevic-Simsic

The aim of this paper was to study sludge dewatering. The sludge which was examined in laboratory scale was produced by neutralization of a mixture of metallurgical wastewaters. Experiments were carried out using synthetic wastewaters with chemical composition similar to that of metallurgical wastewaters, resulting from electrolyte regeneration, copper refining and precious metals recovery. During investigations gravitational and vacuum techniques were examined. Parameters such as water volume, height of sludge and time of dewatering were monitored. In this paper the results obtained are presented and discussed. The application of vacuum filtration enables better dewatering and compaction of sludge.

Jan 1, 2006

By Kurt Zeidler, Vojtech Gall

London Underground Limited are currently constructing an extension of the Jubilee Line. The approximately 16-km long Jubilee Line Extension Project connects the existing Green Park Underground Station with the Canary Wharf area and Greenwich. Being a part of the project, the London Bridge Station (Contract 104) was built using a combination of the New Austrian Tunneling Method (NATM) with Compensation Grouting. NATM was successfully applied in softground and urban areas under restrictive requirements regarding settlement limitation. Information on the flexibility of the method and the influence of Compensation Grouting on ground and tunnels are given.

Jan 1, 1997

By Tom Bruington

This paper discusses the accuracy of determining the quantities of gold and silver on activated carbon in various stages of process for typical precious metals flowsheets. Accurate plant performance evaluation depends upon reliable estimates of carbon and precious metals inventories. The sources of sampling error are identified and methods of reducing them discussed. Several case studies illustrating the sensitivity of flowsheet performance to sampling error are presented.

Jan 1, 1991

By Lynn B. Hales, Randy A. Ynchausti

Expert supervisory control strategies have been used for many years to improve operating revenues in comminution circuits. Typical improvements in capacity range from four to eight percent. Several case studies of results will be presented as well as a general discussion of the technologies used to achieve the improvements. Crushing. SAG milling and ball milling circuits will be discussed.

Jan 1, 1997

By S. B. Leonov, K. I. Popov, S. B. Polonsky

The offered technological line includes a flotation pulp air conditioner operating on the impact-mechanical effect and two column apparatuses with a descending pulp-air flow mounted in series. The technology developed makes it possible to increase considerably the valuable component in the concentrate simultaneously with a reduction in energy consumption for the flotation process. The experience achieved with the technology showed the possibility for obtaining sulphide silver-bearing ore superconcentrates with the noble metal content 2-10 times higher than that in the concentrates obtained by the conventional technology. The same results were obtained in the process of calcium-bearing boron-silicate ore-dressing.

Jan 1, 1995

By Jihong Xue, Jialin Wang, Della Valle Nicola

Experience of Hard Rock TBM excavating soil in Wanjiazhai Yellow River Diversion Project tells us that selection of Hard Rock TBM to excavate soil in case that rock dominates overall length of tunnel, could be a compromise among tunneling speed, cost and quality. Risk of this operation could be greatly reduced with a detailed study of the geomechanical characteristics of the soil and, if the characteristics are suitable, money and time can be saved by using Hard Rock Double Shield TBM.

Jan 1, 2003

By W. J. Pennstrom, J. R. Arnold

Gold Fields installed what was the mining industry's first commercial gold electrowinning/replate circuit at Ortiz in 1981. Its highly successful operation since that time provided the design basis for a similar circuit at Mesquite, which was started in early 1986. These circuits produce plated gold foil suitable for direct shipment to a refinery or melting directly into bars. Detailed descriptions of the electro- winning and replate circuits are given and advantages and disadvantages are discussed.

Jan 1, 1988

By Malcolm Scoble

This contribution examines the motivation and prospects for mining companies to become Learning Organizations and integrate Lifelong Learning into their culture. Mining Schools have a potentially central role to play in developing Learning systems for access by industry. Reference is made to initiatives to develop a system that is based on collaboration between UBC, Edumine and the Canadian Institute of Mining, Metallurgy and Petroleum. Recent experiences with this model are reviewed.

Jan 1, 2005

By R. Krishna

The basic ventilation equation of power equal a constant times quantity to the power three (P=constant x quantity3) makes it an extremely costly palliative as a long term measure. Provision of increased airflow is also limited by maximum tolerable levels of air velocity, the effect upon respirable dust and, in case of coal mines, spontaneous combustion. The paper high lights amelioration measures for climatic improvements at a lower cost. The paper has also shown a method for monitoring air pollution using laser technology.

Jan 1, 1997

By B. Day, L. Elinson

There is general agreement among those involved in occupational and public health that work-related diseases are under-diagnosed and under-reported. Highmark is particularly well positioned to carry out industry health analysis as it provides medical insurance for approximately three quarters of the insured population of Western Pennsylvania including some of the areas largest employers. The purpose of this study is to gain a more accurate understanding of the mining industry rates of respiratory diseases that maybe occupationally related and identify those inflated respiratory disease and hearing loss rates. Conditions examined included COPD, asthma, and pneumoconiosis.

Jan 1, 2004

By Arthur B. Arnold, Curtis T. Scott

The Blue Mountain Tunnel is a part of the Sultan River Hydroelectric Project. The Sultan Project is in the Cascade Mountain Range, approximately 56 km (35 mi) northeast of Seattle, Washington. The geology is structurally complex, consisting of graywacke and argillite, with lesser amounts of metaigneous rocks. The tunnel, excavated with a tunnel boring machine (TBM), is 4.32 m (14 it) in diameter and 6.3 km (3.9 mi) long. The average 24 hour advance was 41 m (134 it) with a maximum of 71 m (234 it). The tunnel is essentially unlined except for 383 m (1,257 it) in a low cover area and in the rocktrap. Inspection of the tunnel after one year of operation showed it to be in good condition with only a minor amount of rock debris in the rocktrap.

Jan 1, 1987

By A. E. Hall

The authors are to be commended for their attempt to provide a convenient piece of software for preliminary drum hoist specification. This field has received little attention in recent years and is eminently suited to calculation by computer. Unfortunately, there appears to be an error in the calculation of the required rope diameter. The 66-mm (2 5/8-in.) rope selected is oversized for this application. Wire rope weight and breaking strength are related to the rope diameter. For a round strand rope

Jan 1, 1988

By MSHA

Not quite a year ago, during a speech to a group of mining professionals in Washington, DC, the subject centered around the long-range importance of conducting research projects and how much that research needs to specifically apply to health and safety matters in our industry. The point was made about the critical need to work together with government, private industry, labor organizations and academia speaking with a unified voice as we all march into the future together. The fundamental benefits of competitive research were mentioned -- to improve our quality of life, to develop our energy resources, to achieve a safe and healthy environment and to ensure long-term economic growth. Very importantly, emphasis was given to the natural link that makes my agency, the Mine Safety and Health Administration, and the National Institute for Occupational Safety and Health -- NIOSH -- the beneficiaries of each other's findings.

Jan 1, 1999

By S. Michael Feroz, Michael J. Britch, Frank S. Buehler

The City of Portland is constructing the Columbia Slough Consolidation Conduit as a part of its commitment to reduce combined sewer overflows into the Willamette River and the Columbia Slough. Known as “The Big Pipe,” the conduit has a 3.7 m. (12 ft.) internal diameter and is 5,640 m. (18,500 ft.) long. Construction Segment 1 of the project includes 250 m. (814 ft.) of reinforced concrete pipe (RCP) installed by boring and jacking. Five separate crossings were constructed beneath Union Pacific Railroad tracks and Columbia Boulevard, an adjacent arterial roadway. This paper describes the design and construction of these bored and jacked crossings.

Jan 1, 1999