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By Deepak Malhotra

Western technology is considered a panacea for all ills in developing countries. Is that really the case? Are inventors of new technology overselling? What are the expectations of the receiving party? The author offers his views on these questions and proposes a process for systematic transfer of technology while minimizing surprises on the part of the seller and the receiver.

Jan 1, 2001

By D. A. Harman

The U.S. Environmental Protection Agency recently recognized Newmont and other mining companies, along with the Nevada Division of Environmental Protection for their voluntary work in reducing mercury air emissions. One example of this voluntary effort is the installation of a reactive scrubber to capture mercury vapor from the exhaust of a carbon regeneration kiln at Newmont’s Twin Creeks Mine. After considering the available technologies, a proprietary reactive scrubber, developed by ADA Technologies, Inc., was selected and is currently being commissioned. Mercury removal rates greater than 90% have been documented.

Jan 1, 2004

By S. Bhattacharjee, S. K. Singh, R. K. Galgali

A method for the preparation of zirconia- toughened mullite using dc plasma is presented. An indigenously developed 50-kW thermal plasma reactor is used for the preparation of zirconia-toughened mullite using a dissociated zircon and alumina mixture. Both XRD and SEM studies of the product confirmed the formation of mullite and zirconia. The zirconia grew as equiaxed grains of uniform size (~5 µm) in a mullite matrix.

Jan 1, 2002

By Xingshen Wang, Xuefeng Liu

This paper introduces the methods of adjustment over air pressure, air quantity and the method of comprehensive adjustment over air resistance during a mine ventilation survey. The method of selection of weight value for the adjustment is discussed. Finally a calculating method in regard to saving computer memory units and speeding up calculating process is described.

Jan 1, 1989

By Gary PE Beerkircher

A brief history of banana screen development and evolution will be presented along with the operational advantages of the large banana screens available in the industry today. Applications of the large banana screens will be presented as well as the economic advantages that the use of large banana screens can offer to the Mining lndustry today. Banana screen installations in metal, non- metal and coal mining applications will be presented.

Jan 1, 1997

By Steven W. Hunt, Jane A. Kettler, Barry R. Doyle

A sewer tunnel being constructed through an urban commercial area was to pass the site of a former gasoline service station. The site was known to have contained leaking underground storage tanks. An environmental assessment of soils on the alignment was performed, and measures were implemented to handle expected contaminants. Despite these precautions, an explosion occurred in the heading when liquid gasoline was encountered. Four workers were injured. This paper presents the findings of an investigation into the cause of the explosion, and examines how concerted efforts by the parties involved failed to prevent it. The level of guidance provided by OSHA Code provisions for tunneling in gassy conditions is discussed.

Jan 1, 1997

By Gregg E. Korbin, Patrick Hamilton

INTRODUCTION The Balsam Meadow Project, presently under construction for the Southern California Edison Company, is located approximately 55 miles northeast of Fresno, in the Sierra Nevada Mountains (Fig. 1). Major components of this project include an underground powerhouse for a 200 MW unit and a high pressure power tunnel/shaft. Site exploration [ ]

Jan 1, 1987

By H. Schultheis

The European Commission has launched in April 2002 the Thematic Network NESMI with-in the FP5 under Growth. NESMI stands for ?Network on European Sustainable Mining and Processing Industries? and will run until 2005. Within NESMI there are different ways to set up indicators and evaluate them throughout the NESMI Members. First analyses concerning the Demand and Competence within NESMI are developed. New focus points for analyses can be implemented into NESMI.

Jan 1, 2003

By Peter Mathias

The ventilation of long headings tunnels has al- ways posed special problems. The authors trace the progress of one such project from the design stage through the practical problems encountered to the final solution.

Jan 1, 1980

The research deals with the study of the quality indicators in the productive process and its use for the consuming market, for two types of ores: industrial sand and crushed stone. Companies who represent the profile of the São Paulo producing market in its respective modalities well produce the selected cases. The development of the studies have to be, for the application of consistent methodological models of the fundamentals of the Engineering of Quality, especially how much to the statistical control of processes and its trustworthiness, of form that the results of the research can serve as referential in the boarding for other generic cases of the mineral industry.

Jan 1, 2003

By Charles Schmidt

Phalabonva (Figure 1) is situated in the northern province of South Africa adjacent to Kruger National Park, about 500 km from Johannesburg. The nearest South African port to Phalaborwa is Richards Bay about 700 km distant by rail.

Jan 1, 1999

By L. B. Hales

Color video or digital cameras have been installed over flotation cells to monitor color, bubble size, froth movement, and other characteristics. These systems are designed so that the camera provides flotation performance information just as any other sensor might. Factorial tests have been run to monitor and measure the variation in froth characteristics as a function of flotation control settings. Ultimately, it is envisioned that froth image sensors can be used to monitor and control the flotation performance as effectively and for less cost than current analytical systems.

Jan 1, 1999

By Tien H. Wu, Pinnaduwa H. S. W. Kulatilake

The concepts of conditional probabi1ity and geometrical probability are used to establish a relation between the probability density of the trace length and the probability density of the discontinuity diameter. The discontinuity is represented as a thin circular disc. A numerical solution scheme is used to obtain the probability density of the disc diameter from the probability density of the trace length. An example was used to illustrate the possibly large difference between the mean discontinuity diameter and the mean trace length.

Jan 1, 1986

By Alwyn Protheroe, Steve Smith, Herbert Jr. Gibson

In September of 2000, Cowin and Company, Inc., contracted with Paramont Coal Corporation to construct a large decline approximately 820 m (2,700 feet) in overall length at a grade of 8 degrees to the Lower Banner Coal Seam. This paper will discuss the methods used by the contractor and owner to overcome the unique problems required to construct this tunnel in a coal mine environment. The problems include, initial design considerations, equipment selection, ventilation, ground control, control of water in?ows, and placement of concrete.

Jan 1, 2003

By Jorge Martinez

The Muck Valley Hydroelectric Project in Northeastern California required construction of a 3.65 meter tunnel through 6,623 meters of mixed volcanic flow deposits within a critical time frame. As Engineer and Construction Manager for the Project, Morrison-Knudsen Engineers invited bids for both Drill and Blast as well as Tunnel Boring Machine methods, selecting a contractor proposing a TBM designed and built specifically for this project which could excavate a wide variety of materials and maintain acceptable progress rates to complete the work within schedule. Tunnel lining as required included shotcrete with metal fibers and full circle concrete.

Jan 1, 1989

By Glenn M. Boyce, Timothy R. Coss

Microtunneling first appeared with some regularity in the United States in 1987. Until then, only Japan and Germany utilized this method of construction. Its high costs initially limited its application to special situations. The last ten years have seen the use of new pipe materials, new machines, new cutterheads, new techniques, and an average growth of30 percent each year. This paper documents the growth and changes that have occurred with microtunneling. Based on current industry practices and advances from abroad, this paper postulates what the next ten years may hold.

Jan 1, 1997

By Gordon F. Revey, Dan Harrison

Hanging Lake Joint Venture recently excavated two conventional 12.8 m (42 foot) diameter highway tunnels in the difficult ground conditions of Glenwood Canyon, Colorado. This paper outlines the type and success of the various Controlled Blasting Techniques that were used to minimize overbreak in the portal and tunnel excavations. The different Smoothwall and Cushion Charge loads used in the different ground types are described in detail. Delay Timing and Drilling Pattern variations are also discussed.

Jan 1, 1991

By Michael E. Lively

DOUG HALBE: We've talked about copper operations and gold operations. For our third section on the topic "Operating Ideas That Have Saved Me Some Bucks," we'll turn to the coal fields. Our featured speaker is, I'm almost embarrassed to say, a mining engineer, Mike Lively. Mike has 25 years' experience in the coal industry. He is currently superintendent of surface operations for Southern Ohio Coal Company, Meigs Division (AEP Company). I've read his paper, and there's some really great information here. Mike.

Jan 1, 1998

By Lynn B. Hales, Randy A. Ynchausti, Robert W. Colby

Process control systems have evolved from single loop control to distributed control with computer based expert control strategies. The next step is to add adaptive control to the expert control strategies. An object-oriented intelligent adaptive optimization approach is defined and simulated results are presented.

Jan 1, 1995

By Maurice Deul

Limestone can be used effectively in treating acid mine water. Aside from a lower cost than for other treatment agents, limestone has the advantages of easy storage and effectiveness even when impure and in slack sizes. Limestone incorporated into waste piles in layers or as riprap can inhibit acid formation; limestone rubble packed in a mine entry offers promise in formation of a low-cost autogenous resilient seal.

Jan 1, 1974