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By P. Anciaux, T. Simpson

The competitiveness of the EU manufacturing industry has come to the forefront of EU politics. The systematic monitoring of developments and the review of the state of the competitiveness of economies and enterprises was identified as an essential component in this process. Work is currently being carried out within Enterprise and Industry Directorate-General in order to analyse the different factors that influence the competitiveness of the non-energy extractive industry. Such an assessment should help to identify policies and actions which could contribute to and enhance the competitiveness of the industry. Assessing the competitiveness and sustainability of the industry implies the need for reliable, consistent data. One important example of how this need is being addressed, is the development of sustainable development indicators (SDI) for the EU non-energy extractive industry. These seek to monitor the industry’s performance and provide a platform for openness and discussion. Work was started on the development of SDIs in 2000, and the first report was published in February 2004.

Jan 1, 2005

By L. Korkiala-Tanttu, M. Rinne, Z. Song

Disposal of mine tailings has been recognized as an unavoidable burden of mining companies and local authorities. Conventional methods dispose mine tailings in a passive manner which hardly generates any value from them. On the other hand, growing local communities close to mines need more infrastructures which require great amounts of raw materials. In view of the above mentioned situation, a novel utilization of mine tailings is explored as alternative material for asphalt pavement, in order to extract more value from mine tailings and solve the high cost of pavement material. Inherent physical properties of the mine tailings were first investigated to find out their availability as pavement material. Then test specimens were made as mixture of the mine tailings and other pavement material to be tested in laboratory. The mine tailing materials presented a considerable potential as asphalt filler for low-volume roads. Furthermore, the limitat

Jan 1, 2011

By J R. "Dick" Daniel

One of the more common tasks in blast management is the adjustment of: shot geometry, explosive energy, and shot timing parameters to achieve changes in blast outcomes and costs. Many of these shot parameters, once a delayed blast is initiated, are modified by the development of new free faces which change the original or static input values to dynamic values. These newly generated dynamic values are easily calculated and find use in fine tuning shot adjustments and in rationalizing blast outcomes in a systematic manner.

Jan 1, 1996

The 118th, meeting of the Institute, which has been arranged primarily for the benefit of the Institute of Metals Division and of those members who are particularly interested in iron and steel, will be held in the Milwaukee Auditorium, Milwaukee, Wis., on Oct. 8 to 11, 1918. This date has been selected because at that time, and at the same place, the American Foundrymen's Association and the American Malleable Castings Association will hold meetings. A notable exhibit of metallurgical and mechanical processes and products, at which over 165 firms will be represented, has been arranged in Machinery Hall, of the Auditorium Building. Wherever practicable, the machinery will be in operation. The program of the Institute's sessions was published in Bulletin 141. A special announcement of the meeting, together with a program of the sessions of the American Foundrymen's Association, has been mailed to every member who was thought to be directly interested in the meeting. A report of the meeting-and of the discussion of papers will be printed in the December Bulletin.

Jan 10, 1918

By S. Mertikas

The purpose of this paper is to set the stage for (1) the determination of the specifications and actions required for a successful development of a system for the management of waste deposits and contaminants resulting from activities in the mineral industries and landfills and (2) the appropriate infrastructure to be developed at the industrial level. The design of this system would be such that its application could be extended to other industries as well. Waste deposits and contaminants from activities in the mineral industries and landfills commonly cause damage to the environment. In addition to precautionary measures aiming to protect against environmental impact, early warning and immediate response to mining hazards and contaminants is a requirement for sustainable development. Hazard detection and control requires continuous and real-time detection techniques, as well as methods for tracing and predicting the motion of contaminants and waste products. The efficient accomplishment of these goals in the minerals industry requires developing an integrated system for environmental monitoring using remote sensing technologies, in combination with advanced image analysis and geostatistical techniques.

Jan 1, 2003

By R. D. Miller, L. Schulte, J. Davenport, D. W. Steeples

Shallow seismic reflection methods were successfully used to delineate the subsurface extent of roof failure associated with the dissolution mining of a 120-m (400 ft) deep and 60-m (200ft) thick salt bed in central Kansas. Surface subsidence at North American Salt's Hutchinson, KS, salt-dissolution well field represents a potential risk to surface structures and transportation facilities. Three intersecting common depth point (CDP) seismic reflection profiles, targeting the subsurface around an actively subsiding sinkhole, possess sufficient resolution to delineate the horizontal and vertical extent of subsurface rock failure associated with the subsidence. The three seismic profiles showed a disturbed subsurface area 90 to 105 m-diam (300 to 350 ft-diam) at a depth of between 60 to 75 m (200 ft and 250 ft). Confirmation drilling verified the interpretation of the seismic data. The seismic reflection method has the potential to resolve disturbed subsurface areas greater than 23 m-diam (75 ft-diam) at this site.

Jan 1, 1994

By R. O. Heckroodt

After a brief review of the characteristics of clay minerals and their origin, a summary is given of the industrial uses of different types of clay materials. The mining and beneficiation of clays are discussed, with special reference to the upgrading of certain types of materials. The occurrence and resources of the more important varieties of clays are dealt with in some detail, viz residual kaolin derived from granite and sediments, brickmaking clays, refractory clays, bentonite, and palygorskite. The Republic of South Africa is well endowed with a wide spectrum of clay materials, with one important exception. Kaolin suitable for paper coating is not known to occur in the Republic, and efforts to beneficiate and treat local materials to achieve the desired properties have so far been unsuccessful.

Jan 1, 1991

By J. W. Sweeney

The .Florida land-pebble mining industry of central Florida was examined to identify trends in land use; conflicts in land use; and the effect of the conflicts on mineral resources. Many conflicts exist in the study area, such as conflicts with other users of land resources and land surface; conflicts with high revenue land users; conflicts for land surface in urban and suburban areas; and conflicting restrictions concerning utilization. Projections are made showing that lands in phosphate company ownership are expected to be made available to help meet the need for future urban expansion in the study area. Some phosphate resources have been lost due to land use conflicts, however, most of the resource loss has been small. Land use conflicts and phosphate mining are reconcilable and considerable progress toward their maximum and multiple use of land and mineral resources can be resolved through farsighted planning based on factual data.

Jan 1, 1972

By J. -C. Roegiers, M. Thiercelin

Accurate toughness determinations are difficult to achieve in the case of soft or heterogeneous rocks. The existence of a large process zone ahead of the crack tip makes the determination of the apparent toughness crack length dependent, in the case of subsized specimens. In order to use practical size specimens, the authors propose a new toughness test, the Modified Ring Test, which pre- vents a largely developed process zone to form ahead of the crack tip. This test has also the advantage that its geometry is core-based. Numerical and experimental results are discussed.

Jan 1, 1986

By W. E. Horst

Historically, research organizations have made significant contributions to the development and commercialization of new chemical products for the mining industry and examples of commercial results are cited With the recent demise of research organizations within the mining industry and dynamic changes in the industry, the supporting role of R&D groups has become limited or non-existent. Cat- reduction requirements and new raw-material sources offer future opportunities for R&D organizations to continue their effective participation in the commerical development of new chemical products. Potential areas of interest for future process applications are reviewed.

Jan 1, 1986

It took the US coal industry 55 years to increase domestic coal production by about 11%-from 568 million tpy in 1920 to today's level of about 630 million tpy. With such a growth record, it would take a few hundred years to double coal production. FEA planners think that it can be doubled in 10 years. "With all the obstacles continuously imposed on coal, the industry's real problem is not growth but survival," says Ray Albrechtsen, board chairman of Mountain States Resources Corp., and "we should consider ourselves lucky if, by 1985, the coal industry won't have been legislated and regulated out of existence."

Jan 5, 1975

By Newell Alford

FORECASTS of future timber consumption in soft-coal mining are handicapped by; the lack of adequate experience records for estimating properly the timber requirements of the industry. Data were obtained from plants where records are kept or from operators who collected the information and to these were added FIG. 1.-GROWTH OF POPULATION IN UNITED STATES, FROM PEARL'S ?BIOLOGY OF DEATH." composite figures for the continental United States in 1905 and 1919 1 and for central and. Western Pennsylvania and for Illinois in 1922.2 The result, representing slightly over 928;000,000 net tons, is shown in Table 1. Some of the companies furnishing data were unable to segregate the timber into classes of use but for those who did, Table 2 shows the board feet of posts and cross bars used per ton of coal mined and the, percentage of the total timber consumed that was used in roof support. The wide variation in amounts of timber per ton of coal mined is the result of

Jan 5, 1924

By W. A. Backofen, M. L. Ebner, D. H. Avery

Slip on (11221 planes, which do not contain a close-packed direction, has been identified on crystals strained at —190°C. Evidence is also presented to show that (1071) pyramidal slip is a mode of deformation at 25ºC in a limited orientation range. PYRAMIDAL slip (l011) <1120> in magnesium at elevated temperatures has been established for some time.1-2 More recently, Burke and Hibbard reported this mode of deformation at 25"C, but their results were questioned by Craig.&apos; Also, as far as the present authors know, slip in magnesium on pyramidal planes of the second order, Type II (1122)) has not previously been reported, although Gilman"," identified (1122) slip in another hexagonal metal

Jan 1, 1959

By Majid Ataeepour, Ernest Y. Baafi

High level programming languages such ass C, FORTRAN and BASIC have been used in the mining industry to simulate truck-shovel systems. In addition, some special languages for simulation such as GASP, GPSS, SLAM, PROOF and SIMAN are commonly used. The most recent simulation system ARENA uses graphical modelling approach as well as animation notion. In this paper, the main elements of ARENA required to perform a truck- shovel simulation and to view the simulation results by means of the model animation are presented. The layout of the haulage system including shovels, trucks and dump sites was generated using draw tool in ARENA. All the components of the haulage system were represented by graphical modules. Animation tool was used to depict the performance of the haulage system as the simulation progressed.

Jan 1, 1996

By J. P. McDonnell, L. A. Beckett, K. Y. Hammy

Dangerously high stress areas can be controlled by proper mine planning and/or destressing. This paper reviews practical methods to detect and destress high-stress zones along coal faces. The US Bureau of Mines investigated stress-related burst problems and destressing efforts at a cooperating mine. Laboratory tests of the drilling yield method for high stress detection were conducted to determine the correlation between the volume of cuttings obtained and the magnitude of the applied stress. A three- dimemiom1 computer modeling program was used to evaluate the effectiveness of stress relief methods.

Jan 1, 1987

By Ronald S. Conti, Harry Dobroski

Re1iabl e monitoring a1ong an underground mine belt line is of great concern because of combustibles, electrical apparatus, and friction. Belt entries are strategically located where a fire can have rapid and disastrous consequences. This paper reviews conventional distributed temperature sensing systems based on resistive, thermistor, and thermocouple effects. These are shown to provide limited benefits. A new system tested by the U.S. Bureau of Mines based on fiber optics and time domain reflectrometry, promises much better temperature and spatial resolution, faster response, inexpensive cable, longer distance, and comprehensive data analysis. Test results in a small, controlled, in-mine fire are given.

Jan 1, 1992

By P. Somasundaran, T. Chen, Diptabhas Sarkar

We have developed a layer-by-layer deposition technique for preparation of nanocomposite particles. Using this process, it was possible to make nanocomposites of various oxides with desired local composition and microstructure. The attachment of the shell particles to core particles was achieved using controlled polymer adsorption. Removal of excess polymer was accomplished without detaching the pre-adsorbed polymers by a specific stepwise washing scheme. The inherent chemistry of the process makes it easy to incorporate functional fillers over core particles. The nanosized filler materials will replace the shell particles in the present process and the polymer bridge would be chosen by taking into consideration the respective surface chemistries of various shell and core particles.

Jan 1, 2003

By W. L. Falke, A. A. Cochran

Vast deposits of low-grade manganese ore exist in the United States, yet domestic production is insignificant compared to the more than 2 million tons of ore imported yearly into this country.1 A basic problem in connection with manganese is to find economical ways to utilize domestic resources.2 As a part of its program to conserve domestic mineral resources and to reduce dependence on foreign sources, the U.S. Bureau of Mines has conducted extensive research to broaden manganese technology and to find economical processes for recovering manganese from these low-grade resources. Although a great many processes have been proposed for treating domestic manganese resources, a failing of many of them is that too many steps are involved for economical operation.2 Some of the major processes that have been proposed were reviewed by Norman and Kirby.3,4

Jan 3, 1967

By Calvin Konya, Theodore R. Myers, Robert Lundquist

The design of a single, large mass blast using ring drilling may take two to three months. This time requirement inhibits the evaluation of multiple designs. It also reduces the flexibility to redesign a blast when a parameter affecting the blast changes. Manual preparation exposes the design of a ring blast to a greater probability of human error. The use of Computer Aided Design (CAD) can help to overcome the shortcomings of manual design preparation. High speed electronic calculation, as well as programming, allow for many designs to be considered before blasting. Parametric programming allows single or multiple parameter changes to be introduced into an existing design, such as changes in drilling equipment, variations in ore density or changes in explosive. Exposure to human error is reduced by programming that performs calculations and produces graphical displays for review by the designing engineer. The goal of achieving desirable fragmentation for the minimum cost, when using ring blasting, is obtainable using blasting design techniques and CAD. Multiple designs can quickly be generated and costed, producing cost curves that indicate an optimum design with respect to cost.

Jan 1, 1990

By G. C. Howell, H. A. D. Kirsten

The mining-induced effects around narrow tabular stopes have traditionally been evaluated in terms of elastic continuum analyses. An understanding of the phenomenological behaviour of the rock surrounding deep-level gold mines has accordingly been developed on the basis of such analyses. However, elastic analyses do not afford reliable representations of the behaviour of rock in which failure may occur on discontinuities. This paper describes investigations that show how the stress and stiffness characteristics of a rockmass are affected under such circumstances for representative ranges of values for the relevant parameters (depth, span, support stiffness, field stress ratio, and discontinuity strength). These investigations afford a substantially different understanding of the mechanical behaviour of rock that is subject to failure. Instead of forming an arch across the abutments, the rock in the hangingwall bears directly across the stope onto the footwall and, instead of being subjected to tension, the nether hangingwall is clamped in compression in the horizontal direction.

Jan 1, 1993