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By Nina I. Fedunec, Olga E. Fomicheva

Results of researches on creation of the intelligent adviser system for mining dispatcher are represented. A method of the analysis of subject domain is considered and results as the generalized expert questionnaire and diagrams are represented. The system-adviser REALTREE, functioning in real time, is represented, results of an estimation of a system effectiveness during decision making by the dispatcher are submitted.

Jan 1, 1996

By Christopher J. Hall

This paper describes the results from computer runs simulating 24 different mine ventilation configurations with the main fan situated first at the top of the upcast shaft and then at the top of the downcast shaft. Real air was used, with evaporation, condensation and heat exchange. The results showed that power requirements for the forcing fan were up to 20% less than for the exhausting fan for equal mass flow rates.

Jan 1, 1989

By Moudgil. B. M.

The amount of hydrophobic materials constituting the mineral froth strongly influences the froth viscosity. Higher truth viscosity, on the other hand, can retard the drainage of physically carried over, hydrophobic particles. In phosphate flotation tests, a direct correlation was observed between froth viscosity and recovery, and an inverse correlation existed between froth viscosity and grade. Phosphate flotation tests in the presence of a silica depressant indicated that higher froth viscosity is an effect rather than a cause for the presence of silica particles in the froth.

Jan 1, 1994

By D. Farahmand

This paper focuses on formulating a practical procedure for forming long-range production and development schedules in underground mining. A computer program developed to be run on a microcomputer is presented and discussed in detail, and a practical case study is analyzed to demonstrate the suitability of the procedures discussed in the paper. The intent of the computer scheduling model is to have quick access to vital information when changes in development and production are under consideration by management.

Jan 1, 1986

By Scott F. Andersen

Discussion to include location and description of the project from upper lake through powerhouse to lower lake, noting locations and size of shafts. Discuss evolution of shaft development concepts in conjunction with owner, contractor and CAL OSHA. Discuss elevator shaft equipment, T1 gate shaft, T2 surge shaft equipment, T3 surge shaft and the incline shaft equipment. Question and answer period.

Jan 1, 1981

By Hisakazu Matsushita, Yoshio Yamaguchi

INTRODUCTION Shinkansen, operating 1,176km between Tokyo and Hakata, transports 340,000 passengers a day. Presently, the 466km Tohoku Shinkansen linking Tokyo and Morioka and the 270km Jyoetsu Shinkansen linking Omiya and Niigata are under construction. It is progressing smoothly and 95% of the civil and architectural construction has already been completed.

Jan 1, 1981

By Chien-Tsun “C. T. ” Chu, Drupad B. Desai, Ron E. Redd

The 12,710-m (41,720-ft) Riverside Badlands Tunnel is located between the most active faults—San Andreas and San Jacinto—in Southern California. To accomplish the impervious final lining design and to accommodate the effects of earthquake ground motions, a new approach was developed and is prescribed in this paper. Two final lining options, welded steel pipe and prestressed concrete cylinder pipe, are considered for the tunnel, which will be excavated under groundwater and ground conditions from soft rock to hardrock at depths exceeding 244 m (800 ft). The buckling strength, serviceability, and structural integrity under seismic effects and other loads were considered in the design.

Jan 1, 1997

By Romeo Jurani, Ralph Dresel, Fred Kissell, Charles Parker

This report describes actions taken to control silica dust at the Yucca Mountain Exploratory Studies Facility (ESF), a tunnel located in Southern Nevada that is part of a scientific program to determine site suitability for a potential nuclear waste repository. The rock is a volcanic tuff containing significant percentages of both quartz and cristobalite. Water use for dust control was limited because of scientific test requirements. A major dust reduction was achieved with an intermediate air cleaning station located on a rear deck of the TBM trailing gear.

Jan 1, 1999

By C. Villa Diniz, A. H. Martins, Fiona M. Doyle

It is proposed that battery grade MnO2 can be produced directly from a manganese ore from Azul Mine in Brazil, by leaching with HCI to remove heavy metals selectively. We are working to find a way of selectively separating Cu, Ni, Co, Pb and Fe from the resulting acidic manganese chloride solution, to detoxify it and produce marketable chloride solution. Chelating ion exchange resins are proving more promising for this separation than solvent extraction with commercially available reagents. Results from batch and column ion exchange tests that characterize the behavior of copper, nickel, cobalt, lead and iron are reported.

Jan 1, 1999

By D. B. Desai, J. T. Waggoner, J. S. Hill, R. R. Redd, S. J. Klein

The 13 km (8 mile) long Riverside Badlands Tunnel is planned for construction starting in 1998. Extensive geotechnical investigations indicate that the 3.7 m (12 ft) finished diameter tunnel will be excavated through soft ground, weak sedimentary rocks, and heavily fractured metamorphic rocks. Nearly 80 percent of the tunnel will be excavated beneath the groundwater level. Tunneling conditions are expected to range from raveling and over-stressed in the sedimentary rocks, to blocky and seamy/crushed with some squeezing in the metamorphic rocks. Two alluvium reaches will require dewatering. The variable and interspersed ground conditions are expected to be a key factor in selection of tunneling methods, equipment, and initial support.

Jan 1, 1997

By Ch. Roumpos

The present contribution investigates the way of applying benchmarking for large-scale open-pit mining operations based on sustainability indicators proposed by numerous institutions or groups of experts. These indicators have been developed taking into consideration the legal and regulatory framework that are in force. However, their scope is not only to declare the mining company?s compliance with all legal requirements but also to represent its economic, environmental, and social performance. In this way, sustainability indicators allow assessment of a company?s capacity to produce commodities, to meet the environmental quality requirements and to contribute to a long-term economic, cultural and social development of the local communities.

Jan 1, 2007

By S. D. Bearden

The world's barite reserve base is adequate for at least 100 years at the current consumption rate. China, India and the United States are expected to remain the leading producing countries, and the United States will continue to be the largest consumer. None of the known substitutes for barium sulfate are expected to impact existing applications. World production in 1995 was 4.41 Mt (4.86 million st), which is about 50% of capacity. Consumption is directly proportional to hydrocarbon well installation activity. Imports are expected to continue to supply more than half of the US requirements.

Jan 1, 1998

By Alfred G. Hoyl

The small miner and small mine have an important role to play in the finding, developing and production of our mineral resources. "Help, not hinder" must be our byword. We must push in every way we can devise to change the adversary position of government and environmental movements. We need the small mines and they must be encouraged, not hindered. Technically excellent and adequate equipment is available, and needed information is also available to the small operation. Environmental questions and problems must be fully considered regardless of the size of a mining operation.

Jan 1, 1987

By S. T. Krukowski

Traditionally the lime industry is governed by market, location, and transportation. These factors also may act as obstacles to global market access. Lime manufacture responds to market opportunities by first focusing on location. Lime markets are diverse and widespread, and ubiquitous occurrences of limestone make development of a widespread industry possible. Lime’s low to moderate unit value restricts transporting it long distances. Other factors (including lime reactivity, dedicated container use and other liabilities) limit shipping lime far. In the past many small to medium size companies made lime for local use. Today the global aspect of the industry is ownership by few large companies producing lime for local consumption.

Jan 1, 2003

By K. N. Hebbar, R. G. Reddy

Spent potliners (SPL) were declared hazardous waste under RCRA (K088) in July, 1990. The glass formation characteristics of the SPL was studied. The SPL glassy matrix were analyzed using X-ray diffraction and optical microscopy. Results showed that SPL can be fixed in a glassy matrix with the addition of sand and limestone. The optimum amounts of additives were determined for obtaining the best glass formation characteristics.

Jan 1, 1995

By Jorgen Elbrond, Xiaoli Tang

In this paper we apply continuous-time option pricing theory (Dixit 8 Pindyck 1994) to show how to obtain an optimal investment rule for a mining project which requires sequential in- vestments. The application per se is to some extent very simple. The main purpose of the paper, however, is to draw the attention of mining people to how the option pricing theory may be used to capital investment decisions. This topic in economics is quite new but is attracting a lot of attention.

Jan 1, 1996

By N. B. Greninger, M. J. Sapko

The US Bureau of Mines conducted, through joint funding with the Colorado Mining Association, large scale oil shale rubble fire tests to investigate flammability characteristics and different methods of extinguishment. Ignition of large rubble piles was easily accomplished. Foam blankets could be used to control surface flames. The results of these large scale tests confirmed that water was effective but not particularly efficient in extinguishing deep seated oil shale fires. It took up to 1.7 times as much water to extinguish afire as anticipated on the basis of a simple cooling model, assuming 100% utiliza-

Jan 1, 1991

By M. Kockler, S. J. Jung

Underground operations at the Rain Mine averaged 360 tonne/day (400 ton/day) utilizing underhand drift-and-fill and longhole stoping with delayed fill between 1993 and 2002. Mining from four ore zones produced over 803 800 ore tonnes (886 000 tons) at a grade of 9.32 gm/tonne (0.270 oz/ton). Even though openings in the ore could be as large as at 9 m (30 ft) wide, 30 m (100 ft) high, and over 60 m (200 ft) long, the weak rock surrounding the ore zones restricted development size to 3 m (10 ft) wide by 3.7 m (12 ft) high.

Jan 1, 2004

By Shuyu Qin, Shujiang Sun, Jingfu Zhao

The three key parameters of mine fires are local airflow velocity, temperature and oxygen concentration. According to the theories of seepage in porous media, heat transfer and heat dispersion, mathematical models were constructed based on the three parameters. The models can be used for early prediction of mine fires and for estimation of the level of spontaneous combustion. Proper use of the models can assist in preventing and controlling mine fires. KEY WORDS: airflow velocity, temperature, oxygen concentration, numerical modelling, mine fire prediction.

Jan 1, 1993

By John D. Welsh

Heap leach pad liners are important to leach operations for maximizing recovery of gold bearing solutions and minimizing potential environmental impacts. Liners must be designed so that they can be built economically, but careful attention must be paid to the potential for liner damage during installation or placement of ore on the completed pads. This paper summarizes field experience gained on several leach pad construction projects in Nevada. Both soil and synthetic membrane installations are discussed. Emphasis is placed on principles that should be considered during design to provide economical and practical leach pads.

Jan 1, 1987