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By Russell E. Martin

Excavating and lining twin interstate highway tunnels each 11.3 m (37 ft) high by 14.6 m (48 ft) wide by 183 m (600 ft) long. A discussion of the geology of the site and problems occurring at the portals and the solutions to the problems. The methods used in placing the concrete lining are also discussed.

Jan 1, 1987

By V. F. Swanson

A mathematical model for free and hindered settling of minerals was developed. This paper describes how to apply the model in designing systems, such as fluidized bed, elutriation, mixing pumping systems, involving solids and fluids.

Jan 1, 2000

By Gunther Riedmuller, Johann Golser, Peter Schubert

The paper deals with the experience of the authors to cope with tunnel projects in heterogenous and weak rocks. The procedures applied to the investigation of such areas, the geotechnical assessment, the choice of tunnelling methods, the preparation of contract documents and the main features of NATM tunnelling to adapt to these conditions are outlined.

Jan 1, 1993

By M. Phillip Jameson, Paul Sennett

The beneficiation of kaolin by flotation has been practiced on an industrial level since 1961. A brief history of industrial kaolin flotation is given, with a description of the various processing schemes used by the companies that practice kaolin flotation. Some of the areas where improvements could be made in the beneficiation of kaolin are given.

Jan 1, 1989

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 M. L. Young, M. S. Klima

Hindered-settling columns are used throughout the minerals industry for both size and density separations. In this study, the performance of a continuous laboratory-scale hindered-settling column was evaluated for various particle systems. The test variables included solids composition, water rate and column height. Column performance was evaluated using partition curves and corresponding performance parameters.

Jan 1, 2000

By C. M. Brown

Common operating philosophies and objectives of mining and mineral process operations are discussed. Key information required to effectively monitor operations is reviewed in conjunction with the impact of external variables such as commodity price changes on strategies adopted.

Jan 1, 1991

By Gerd Oberheuser, Hans Kellerwessel

Comminution with high compression roller mills finds rising interst in ore and minerals industry. Energy saving and upgrading of existing grinding facilities is one of the main reasons. Beside these possibilities other positive effects on the downstream units operations require also intense testwork. Basic interdependencies of the operational parameters gained at the testwork and their influence on the upscaling procedure are described.

Jan 1, 1995

By R. K. Davey

Before the introduction of computerized procedures, mineralization modeling (compilation of level maps), ultimate pit studies, ore reserve compilations, and long-range mine planning all were performed manually. In fact, much of the basis for today's computer programs was derived from manual procedures and actual experience of mining engineers and geologists.

Jan 1, 1979

By Charles D. Litton

This paper presents a description of the hazards of smoke from fires, the detectability of smoke using smoke sensors, and the operational characteristics of such detectors. It places in perspective the advantage that smoke detectors have over other forms of fire detection and also provides a discussion of smoke as a significant fire hazard.

Jan 1, 1992

By Frederick H. Parkinson, Joseph Fernandez, David E. Westfall

The April 13, 1992, flooding in the freight tunnel network under the city of Chicago had a profound effect on the nearby Chicago Transit Authority (CTA) subway service. This paper provides an overview of the evaluation techniques, mitigation measures, and water control efforts used to maintain the integrity of the subway tubes. Specific topics discussed include visual inspections, inflow monitoring, structure and soil testing and sampling techniques, and the development and implementation of chemical and cementitious grouting programs.

Jan 1, 1993

By H. Reginald Hardy, Maochen Ge

Data analysis is one of the most important steps required for the successful application of the acoustic emission/ microseismic (AE/MS) technique. A dedicated computer software package to analyze acoustic emission/ microseismic data associated with field applications in the geotechnical area has been developed recently at Penn State University. This paper addresses the major features and applications of this computer software package.

Jan 1, 1986

By John A. L. Campbell

Are safety concerns justified regarding the potential for a gas explosion due to recirculation when a scrubber is used on a continuous miner? The role of a respirable dust scrubber on a continuous miner section using blowing face ventilation is examined in this paper and the above question answered. Methane control using high efficiency scrubbers coupled with blowing face ventilation is promoted.

Jan 1, 1987

By J. Muir

This report focuses on minimum ore block sizes that are economically feasible to mine with the vertical crater retreat (VCR) method. In 1985, Homestake Mining Co. began a program to bring several small block VCR stopes on line. This report examines these experimental stopes, including design parameters, ground control, drill patterns, secondary blasting, and mucking. Cost and scheduling comparisons are made with mechanized cut-and-fill and open cut- and-fill methods.

Jan 1, 1987

By T. V. Vasudevan

Floc properties such as density, size, size distribution, porosity, and shear strength govern the effectiveness of flocculation as a process for solid-liquid separation. The floc characteristics desired for removal of suspended solids by sedimentation or filtration, for example, are known to he different. In this study, an attempt has been made to evaluate the effects of various physical and chemical factors on the density and shear strength of the flocs.

Jan 1, 1990

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 Jack K. Lemley

This paper will provide an update of the Channel Tunnel Project including a discussion of the overall legal structure and management organisation. It is important to understand the mission that TML, as a design/build contractor, has undertaken and how the various interfaces have evolved between the other entities involved in the project. The paper will describe the evolution of the management organisation and the approach to completion of our contract, recapping the historic events and moving into a projection of how we will manage the completion of this very large transportation system.

Jan 1, 1991

By M. G. Yalçin

Marbles commercially known as the Nigde- white crop out in the town of Gümü?ler, around the Çalkama Hill within the Gümü?ler Formation of the Nigde Masif of Paleozoic age. Marbles sporadically occur within the masif, however its prevalent occurrence is associated with the Gümü?ler Formation. Due mainly to its intense fractured nature, the Nigde-white marbles are used as dimension stones, crushed stones and most recently micronized calcite. Insignificant portion accounts for block use through a few quarries.

Jan 1, 2005

By S. D. Thompson, G. T. Lineberry, A. J. Basu

Conveyor belt haulage has become the preferred mainline transport method in underground coal mining, especially for multi-unit mines. Proper designs for belts (width and speed) and surge bins (placement, capacity, and discharge rate) are necessary to achieve efficient mine haul- age. Two computer simulation models, CMBCS and BELTSIM, available for designing these parameters were compared. These comparisons included modeling, input data requirements, statistical flexibility, accuracy of simulated loading, and execution time.

Jan 1, 1991

By A. Mai, J. S. Wakeman

The progress results of a pilot plant study on the effects of ball top size and other mill operating parameters are reported. Test series on taconite and quartzite crude ores using a 1.7-m diam primary mill in closed circuit with a vibrating screen indicate clear trends on the improvements of mill throughput and power consumption when using larger diameter balls. Possible effects on mill liner and ball consumption as well as future research plans are discussed.

Jan 1, 1987