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By W. C. Peters

Geologists take the role of mine geologist when they apply their science to the design and operation of a specific minerals project. In doing so, they use the entire spectrum of procedures in economic geology and engineering geology to deal with a specific system of orebodies and associated environment. The objectives are established by stages in the life cycle of a mining operation as it goes from a prospect to a development project and on to a mine. This paper summarizes the elements of a mining geologist's role, with examples highlighted from the preceding papers.

Jan 1, 1992

By Y. Akin

The floatability of a typical boron mineral, colemanite (Ca2B6O11.5H2O), is shown to be hindered by the presence of montmorillonite type clay minerals. The clay is found to act in the form of slime coating. The mechanism of slime coating is investigated using pure colemanite and clay and their mixtures with an anionic reagent in a microflotation cell. Adsorption, flotation, solubility, zeta potential and scanning electron microscope studies reveal that slime coating occurs through electrostatic attraction. It is possible to minimize the effect of slime coating either at high surfactant concentration or at high pH values.

Jan 1, 1997

By L. M. Gochioco

The Seismic Interactive Interpretation Workstation (S//W) provides a wide spectrum of utilities ranging from improving field acquisition techniques, data processing and interpretation of coal seismic data. The power of the workstation lies in the interpretation process where various sets of geophysical and geological data are integrated to form a network of information that is stored in a database. Computer models are generated from known borehole and geologic information and later cross-correlated with the processed seismic data. Structural and stratigraphic modeling techniques add another dimension to the interpretation process. Complex trace attributes highlight subtle features not easily observed in black and white sections. Using the computer workstation, the explorationist gains valuable insight and conducts more intelligent interpretation of seismic data through a more comprehensive network of data analysis.

Jan 1, 1992

By D. W. Fuerstenau

The flotation behavior of quartz in the presence of alkyl ammonium acetates as a. function of alkyl chain length has been interpreted in terms of hemi-micelle formation at the solid-liquid interface. The van der Waals cohesive free energy that is responsible for hemi-micelle formation has been found from these results to be 1.02 kT per CH group. This 2 is in excellent agreement with literature values obtained from research on the properties of micelles in bulk systems.

Jan 1, 1964

By Hayward B. Oblad, Anthony G. Fonseca

Coal flotation has been practiced since about 1920 in Europe and since about 1926 in the U.S. Over 200 U.S. coal preparation plants now use the process to recover coal. Over the 60 year period, the fundamental principles upon which flotation is based have been enumerated, but the interaction between the parameters that affect flotation has not been quantified and a useful model which accounts for these parameters has not yet been developed. A comprehensive and user friendly kinetic model coupled with better process monitoring and control instrumentation would allow plant operating personnel to better predict flotation performance and better control the flotation process in coal preparation plants.

Jan 1, 1989

By Richard Klimpel

The influence of selective chemical dispersants on the hydrocycloning of a copper ore slurry is illustrated. In the % solids and slurry feed rate ranges associated with industrial practice, desirable changes in both d50 and Sharpness Index values of classification were measured with the use of chemical as compared to tests with no chemical usage.

Jan 1, 1981

By L. M. Gochioco

The Seismic Interactive Interpretation Workstation (IIW) integrates various sets of geophysical and geological data to form a network of information which is stored in a database. Computer models are generated from known drillhole information and later correlated with the processed seismic data. Seismic color processing adds another dimension to the interpretation process. Complex trace attributes provide better definition of subtle features not easily observed from black and white sections. Utilizing the computer workstation, the explorationist gains valuable insight and conducts more intelligent interpretation of seismic data through a more comprehensive network of data analysis.

Jan 1, 1989

By R. J. McGregor

The Internet has revolutionized worldwide communications. Any real or perceived mining incident or environmental spill, no matter how small or remote, can become a disaster of "biblical proportions" through the judicious use of the Internet by environmental and anti-mining groups. In addition, mining companies' own Web sites and unofficial message boards can provide plenty of additional ammunition to the anti-mining forces. This paper explores how the Internet and readily available information are used by anti-mining groups active on the Web.

Jan 1, 2001

By S. Mukusha

Electronic spreadsheets are the most common and readily available software applications for analyzing and modeling quantitative problems. Spreadsheets can offer a vast array of opportunities for the analysis and modeling exercises encountered in the field of geomechanics. This study explores the potential for using spreadsheets of in the practice geomechanical engineering. The study also examines some of the barriers to widespread use of spreadsheets. Best practices and guidelines for overcoming potential pitfalls are discussed and highlighted through a case study.

Jan 1, 2000

By M. Mankosa, G. Taylor, G. Luttrell, J. Yasalonis

Several industrial-scale HydroFloat separators have recently been installed at Mosaic’s South Fort Meade beneficiation plant for the purpose of improving phosphate recovery and throughput capacity. This technology was implemented after numerous laboratory, bench-scale, and on-site, pilot-scale test campaigns. The results from this detailed test work provided sufficient justification for the complete retrofit of the existing coarse and ultra-coarse flotation cells. Data indicate that the metallurgical results obtained with the full-scale separators are consistent with that obtained during both the bench- and pilot-scale evaluations. The apparent benefits, theory of operation, and commissioning of the equipment are also discussed.

Jan 1, 2007

By Edward M. Dowey

This paper presents the excavation of the Roosevelt Island Valve Chamber, the final of three chambers in Stage One of New York City's Third Water Tunnel. The valve chamber and passageways 13 379.7 cu m (17 500 cu yd) are drilled and blasted. The rock is stabilized by grouted rock anchors. The 6.1 m (20 ft) diameter shaft is drilled, blasted, rock bolted and wire meshed for a depth of 70.7 m (232 ft). Then shaft excavation proceeds with immediate concrete lining for another 120.7 m (396 ft). Two 6.1m (20 ft) diameter manifolds are excavated using heading and bench. The raise drilling of eight 3.7 m (12 ft) diameter laterals occurs during lower shaft sinking.

Jan 1, 1987

By I. J. Lin

The effect of various types of structural modification on the critical micelle concentrations (CMC) and hydrophile lipophile balances (HLB) of certain surfactants has been considered. Using the concept of effective chain length for the substituted species, an index of hydrophobicity (I) has been defined. It is hoped that such an index will allow one to choose surfactants for particular purposes in a less arbitrary fashion than heretofore.

Jan 1, 1973

By Edward M. Belsky

Increasingly stringent government environmental regulations will affect the availability and costs of bonding and insurance products for the mining community. New regulations requiring Environmental Impairment Insurance, Reclamation Bonds, and Cyanide Use Bonds will result in both an increase in cost and a decrease in availability of affordable insurance and bonding pro- ducts. Professional Liability Insurance for engineers that covers pollution exposures will be a must for all professional engineers working in the mining community. By understanding the problem, solutions can be structured to allow your company to obtain the mandated insurance at the most favorable cost and conditions!

Jan 1, 1991

By F. Duan, W. G. Pariseau, C. S. Schmuck

Three dimensional comparisons between calculated and measured displacements in the hanging wall of a rock mechanics study region at the Homestake Mine show correlation coefficients of 0.7 or higher. Two and three dimensional back analysis of the data lead to different scale factors for determining rock mass strengths and moduli from laboratory values and seemingly to different rock mass properties. A simple analytic model suggests that indeed not only are there two independent scale factors, one for strength and one for moduli, but that there is a logical relationship between the scale factors obtained from two and three dimensional back analyses of the same mine measurements. The three dimensional modeling procedure implemented in the finite element code UTAH3 thus seems to have a realistic potential for investigating underground hardrock mine questions not amenable to two dimensional analysis.

Jan 1, 1987

By R. Matikainen

Since the Brundtland Commission in 1987, the use of natural resources has been an issue of global concern. Minerals are among the most important Earth resources and will definitely be essential for the development of societies also in future. Increasing scientific effort is needed not only to discover new deposits, but also to promote resource management in ecologically and socially sound way. Sustainable resource management is essentially a multidisciplinary challenge of developing life-cycle analysis and recycling of non-renewable resources from local to global scale. It offers great opportunities for geological surveys not only in EU, but all over the world to contribute positively to the welfare and sustainability of societies.

Jan 1, 2003

For the past four years, the Department of Mining Engineering at the University of Kentucky has conducted a validation study of the CFD Fluent code, by comparing its results against mining-related benchmark experimental data provided by NIOSH?s Pittsburgh Research Laboratory. This particular study is dedicated to the effect of machine-mounted dust scrubbers on the performance of face ventilation systems using extended-cut mining with a blowing curtain.

Jan 1, 2009

By J. D. Christensen

In August 1987, we marked the tenth anniversary of the Surface Mining Control and Reclamation Act. Anniversaries are supposed to be times of celebration, and I truly believe that we have something to celebrate on this anniversary. For, after ten years, there has been much progress in the implementation of the surface mining law.

Jan 1, 1988

By R. K. Simpson, C. S. Eldridge, M. H. Tyler, J. P. Hodgkison

The WMC Olympic Dam Operation in South Australia is an integrated site, involving brown fields exploration through to production of copper cathode, uranium oxide, gold and silver bullion. The Geology and Analytical Services (GAS) Department reflects this totality and, therefore, is perhaps a unique construct in the industry. It comprises Geology, the Metallurgical Laboratory and the Analytical Laboratory, offering a single point of contact in matters of metal discovery and tracking through mine design, production, beneficiation and final product certification. This structure promotes value adding by removing traditional barriers between groups that can deliver more, collectively, than as individual units. This approach to value adding by bringing disparate groups together is echoed in each of the three sections where enhancements in the traditional value adding activities have been delivered by multi-skilling and encouraging overlapping involvement.

Jan 1, 2002

By T. A. E. Breen

A new high intensity grinding technology has been developed and is now being commercialized by Hicom International of Australia. This has led to the development and manufacture of Hicom 120 grinding mills which are now being sold internationally for a range of mining industry applications. The first commercial process application has been for the diamond sector, where the ability of the mill to remove host kimberlite rock by attritioning, with no damage to the thereby liberated diamonds, is seen to be a most beneficial attribute. There are, however, many other mineral industry applications for this mill. The design of the Hicom mill is unique. Based on a high speed centrifugal motion of the grinding chamber, very high power intensity is delivered to the grinding process. Most significantly, a high acceleration field, 50 times stronger than gravity is produced, creating very high power input per unit of mill volume, and exceptionally fast particle breakage rates, typically 50 - 100 times greater than those in conventional tumbling mills. A mill developing such forces has significant implications to comminution technology and practice.

Jan 1, 1999

By T. S. Spicer

Inflammability and crossing point apparatuses were used to study the influence of increasing amounts of such inerts as ash, fly-ash, pyrite, limestone and Portland cement with several pulverized bituminous coals. The results indicate that it requires large proportions of inerts to substantially suppress the ease of ignition.

Jan 1, 1962