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By B. M. Das, V. J. Hucka, J. H. Tu

Subsidence can cause serious damage to surface installations such as railroads, highways, pipelines, buildings and other facilities over a period of many years. Although total elimination of the effects of subsidence is difficult, the damage can be minimized through a systematic analysis. An example of such a study for reducing the effects of subsidence on pipelines is presented in this paper. Subsidence-induced stresses on a pipeline over some coal mining properties in Utah have been analyzed using a computer with graphics capabilities. The results are useful in predicting the extent of damages due to mining subsidence. In view of the gradual replacement of room-and-pillar mining by longwall with caving, this sort of analysis will become more and more important. In the next phase of this study the predicted results will be compared with the permissible stress levels on pipelines over actual subsided areas in an actual case.

Jan 1, 1989

By William J. Dimond

Computor analysis has opened a new world of information for the mining of resources. This paper is directed at the mining of coal. The same procedures apply to most mining projects. The available facts when evaluated against the variables produce the answers. The project must be carefully analyzed, so that the facts can be organized in a data file. The file can be expanded as additional information is obtained during the entire life of the mine. If the mine is pre-planned, the file will be expanded in an orderly fashion and updated information will be available at all times. The development of a property goes through several phases; Exploration, Economic Analysis, Development, Production, and Reclamation. Each phase is an expansion of the data file. The validity of the answers is directly related to the accuracy and quantity of available data. The basis for a data file is horizontal position, and elevation of each piece of information. A coordinate system and datum are reference for a digital (X, Y and Z) position in a spatial system, a three dimensional digital model of the mine. The current practice is to use the State Plane Coordinate system and elevations as established by the U. S. Coast and Geodetic Survey. Each state has adopted this system by law. In the event there is litigation, it is an advantage to have the data on the legally recognized system. The control must be expanded so that all data can be assigned a digital position, and planned to fulfill the requirements for all phases of the mining operation. The project must be analyzed to insure that the objectives can be achieved without duplication or loss of time. sufficient data must be available to reach each required level of information. The coal data can be defined in two categories, spatial

Jan 1, 1977

By Stanislaw Wasolewski

Computerized systems for ventilation parameters monitoring which are used in Polish coal mines provide the ventilation staff with a great number of measuring data. These data can be used to get knowledge about dynamic properties of ventilation process and disturbances affecting its state. This is necessary to create a reasonable concept of mine ventilation control system and make a practical application of such system. In the paper a method of ventilation process identification with the use of measuring data from monitoring system is described. Computer analysis of time series including statistical, correlation and frequency methods are applied to estimate dynamic properties of ventilation process and its disturbances. Using the Fast Fourier Transformation (FFT) algorithm the parameters of the process have been obtained which can be efectively used in a system for mine ventilation control.

Jan 1, 1991

By Richard Klimpel

This paper describes the effects of slurry viscosity on the selection-for-breakage and breakage distribution parameters in the wet grinding of ores. A series of experimental tests were run on laboratory scale ball mills. Slurry viscosities were modified by varying the solids/water ratio with and without the presence of selected chemicals. Very consistent and predictable correlations are shown to exist. The grinding parameters were calculated using a computerized back-calculation technique developed by Klimpel and Austin. Industrial scale circuit calculations and preliminary plant trial data suggest that considerable increases in throughput and/or fineness of grind can be achieved through the judicious use of chemical additives.

Jan 1, 1977

By Willie Manfrey, Richard Klimpel

This paper describes the effects of slurry viscosity on the selection-for-breakage and breakage distribution parameters in the wet grinding of cres. A series of experimental tests were run on laboratory scale ball mills. Slurry viscosities were modified by varying the solids/water ratio with and without the presence of selected chemicals. Very consistent and predictable correlations are shown to exist. The grinding parameters were calculated using a computerized back -calculation technique developed by Klimpel and Austin. Industrial scale circuit calculations and preliminary plant trial data suggest that considerable increases in throughput and/or fineness of grind can he achieved through the judicious use of chemical additives.

Jan 1, 1977

By M. I. Brittan, E. J. J. van Vuuren

Computer analysis, modelling and optimization of gold recovery plants of the Anglo American Group by M. I. BRITTAN M.Sc. (Eng.), M.S., Ph. D., (Member). and E. J. J. van VUUREN M.Sc., (Visitor). Multiple correlation and regression techniques are used to analyse gold plant operating records. Key variables m the process which Influence the gold recovery are Identified and assembled into a mathematical model. This constitutes a valuable tool for the optimisation of variables such as the rates of reagent addition and for assessing the economics of extending the plant. Substantial short term economic benefits have been realized. The techniques provide a rapid diagnostic service without interfering with normal plant operation. Quantitative results are presented and their implications examined. The value of the method is discussed.

By Neil T. Davie, Thomas K. Blanchat, Thomas C. Togami, Joe R. Weatherby, Dale S. Preece, Robert A. Benham, James J. Calderone

"Geotechnical structures ,such as underground bunkers, tunnels, and building foundations aresubjected to stress fields produced by..the gravity load on the structure and/or any overlyingstrata. These stress fields may be.. reproduced on a scaled model of the structure byproportionally increasing the gravity field through the use of a centrifuge. This technology canthen be used to assess the vulnerability of various geotechnical structures to explosive loading.Applications of this technology include assessing the effectiveness of earth penetrating weapons,evaluating the vulnerability of various structures, counter-terrorism, and model validation. Thisdocument describes the development of expertise in scale model explosive testing ongeotechnical structures using Sandia’s large scale centrifuge facility. This study focused onburied structures such as hardened storage bunkers or tunnels. Data from this study was used toevaluate the predictive capabilities oft existing hydrocodes and structural dynamics codesdeveloped at Sandia National Laboratories (such as Pronto/SPH, Pronto/CTH, and ALEGRA)."

Jan 1, 1998

By Neto J. A N

Usually there are organisational interfaces between each stage - companies or departments. Each organisation will have different ideas about "optimum" operation. These ideas will be driven by how the performance of each is measured ' and rewarded. Therefore it is important to set up data acquisition processes with respect to maximisation of overall profitability and resource utilisation. In the simplest case - if the miners are paid on tonnes and the concentrator has severe grade penalties on concentrates, then there is the possibility of a conflict of interest over metal Balance.

Jan 1, 1991

By R. Larry Grayson

A survey of 1250 surface and underground coal mines across the United States was made according to a stratified sampling technique based on national coal districts. A total of 171 responses (13.7% response rate) have been returned and summarized, giving a picture of computer usage in the coal industry. Overall, 63.5% of the respondents use computers, but the percent varied from 100% for large mines to only 44.1% for small mines. As expected, a proliferation of microcomputers has pervaded the industry. Importantly, in spite of the high usage of computers in the industry, sophisticated engineering applications have not yet burgeoned.

Jan 1, 1989

By B B. Beamish, M S. Kizil

The processes that take place during the development of a heating are difficult to visualise. Bulk coal self-heating tests at The University of Queensland (UQ) using a two-metre column are providing graphic evidence of the stages that occur during a heating. Data obtained from these tests, both temperature and corresponding off-gas evolution can be transformed into what is effectively a video-replay of the heating event. This is achieved by loading both sets of data into a newly developed animation package called Hotspot. The resulting animation is ideal for spontaneous combustion training purposes as the viewer can readily identify the different hot spot stages and corresponding off-gas signatures. Colour coding of the coal temperature, as the hot spot forms, highlights its location in the coal pile and shows its ability to migrate upwind. An added benefit of the package is that once a mine has been tested in the UQ two-metre column, there is a permanent record of that particular coals performance for mine personnel to view.

Jan 1, 2005

By P. Felix

A discussion on the need of visualization and animation tools in modelling solidification processes is made. An outline of an approach for the production of a video computer animation is provided. A number of examples including, 2 and 3 dimensional melting, filling, and macrosegregation are presented.

Jan 1, 1993

By Moshe Sheinkin, Burke O. Trafton

This paper describes the use of a computer in analyzing the expected return on a mining venture. The computer program is designed to incorporate all aspects of a mining project, including the mine, mill, smelter, and refinery. Data input may consist of the operating variables in each phase such as the mining rate, grades, reserves at the mine, and the technical operating characteristics of the mine, mill, smelter, and refinery. Detailed tax computations are shown for a domestic operating company, for a foreign company and for a foreign subsidiary. In addition, the use of the various options that are available such as expense write-offs or deferments to create tax credits during preproduction years are considered, and its effect on the DCF. The program is also constructed to accommodate changes in metal prices, and escalation of capital requirements and operating costs. Output consists of profit and loss statements for entire projects using different methods of depreciation, cash flows, discounted cash flows, net present value and returns on investment. Returns on investment are computed for equity investment, total investment, and total investment less tax credits. Allowances are made for bank and guaranteed loans. Additional financial statements can be made for the following: a) A mine-mill segment with a concentrate selling schedule b) A mine-mill-smelter complex with a smelter product selling schedule c) Profitability of the smelter separately d) Profitability of the refinery separately

Jan 1, 1969

By Rogerio Castejón

The evolution on the computer in the last 10 years have caused a big change on the way the mining companies are doing exploration. The following factors have contributed to that change: the downgrade of computers and software cost associated with the “usability” (easy of use) of the present systems (remember the old DOS and UNIX systems). New systems are more focused on the users rather than on the experts in applications, meaning that the geologist must understand geology and not operational system, programming, etc. Market conditions requires exploration to be faster and more intelligent than in the “old” times, and companies are always demanding quicker answers from their geologist group as well as lower exploration budgets. Exploration teams must be more effective and efficient. In this sense, the only way to achieve those requirements is to use the proper techniques, methods and tools on the diverse stages of exploration. Its necessary to consider that the costs of data acquisition increase, almost exponentially, through the stages of exploration, from grass roots to advanced stage.

Aug 25, 2002

By Raymond K. Will

Computers are becoming increasingly valuable tools in the mining industry as a greater variety of appropriate hardware and software becomes available, combined with greater acceptance by management, Within a given time period an engineering staff can evaluate or design a project to much greater detail and higher accuracy by utilizing computers once suitable programs have been developed. We are all aware that throughout the world the decreasing grade of minerals coupled with increasing waste to ore ratios necessitate larger capacity, longer term mining operations and attendant higher capital costs. Computers can be of assistance in all stages of mineral exploitation, from geologic exploration through mine feasibility studies and design, to marketing and transportation. Because of the high speed with which data can be digested and manipulated by computers, preliminary information from any stage of investigation can be analyzed to assist in further guidance of that stage. By use of preliminary mine feasibility studies, financial forecasts and sensitivity analysis, even information from a far-removed phase such as marine transportation of the product, can help guide the exploration phase to a realistic target.

Jan 1, 1973

By Tribhawan N. Srivastava

The Henderson Mine started production in 1976 utilizing a unique, push-pull, mine ventilation plan. As the mine expands in size, the mine ventilation requirements will increase and a more comprehensive system for maintaining ventilation will be needed. A computer simulation study was completed and has resulted in a revised, systematic, mine ventilation plan which is being implemented as mine development proceeds. Based on the computer simulation study, the new ventilation plan takes into account mining of the orebody simultaneously from both the 8100 and 7700 production levels. Present experience and empirical data indicate that volumes of air needed to adequately ventilate both production levels cannot be obtained utilizing the existing mine layout. The total volume of air needed for the mine excluding haulage tunnel will increase from 708 m3/s (1 500 000 cfm) to 1652 m3/s (3 500 000 cfm), thus a new No. 5 exhaust shaft and connecting drifts are being developed to expand the mine ventilation system to service both production levels. The original ventilation plan for the 7500 haulage level was to bring air from the No. 2 and No. 3 intake shafts and exhaust it through the 94X raise to the 8035 exhaust level and then through the No. 1 exhaust shaft to surface. Control of air volumes in loading drifts was initially planned to be achieved by air doors and air curtains. Air doors on the 7500 level require large cutouts, expensive installations and constant maintenance. The computer simulation study indicates that air- flow in the 7500-level production drifts can be con- trolled exclusively by air curtains which are less expensive to install and more effective in regulating airflows than air doors. Air from the 7500 level can be exhausted through a new raise to the new 7635 exhaust level and then through the new No. 5 exhaust shaft.

Jan 1, 1982

By Roy R. Weil, John A. Dziubek

This paper discusses the use of computer modeling, data manipulation, and mapping of three multi-seam coal properties in the Appalachian coal basin. Each case history represents a slightly different application of computer usage for estimation of reserves and planning surface mine sequencing. This practical use of computers demonstrates the suitability of data processing for normal evaluation of coal properties.

Jan 1, 1983

By Robert M. Owen

Recent advances in coring technology and in the development of shipboard and/or in situ geochemical geochemical analysis systems have greatly improved our ability to collect and analyze exploration samples, particularly for marine placer exploration programs. The potential benefit of these improvements cannot be fully realized, however, until we also develop more efficient methods of data reduction and interpretation. Specifically, there is a need to provide prospectors with rapid and useful interpretations of the raw geochemical data so that they can exploit promising results and otherwise optimize the exploration program while the exploration vessel is still at sea. The goal of this project has been to identify and/or develop computer software which is capable of making the necessary data reduction calculations and which can be run on conventional desk-top computers. All work on this project has been supported through a research grant from MMTC-CSD to The University of Michigan. The first stage of this effort involved an evaluation of commercially available (i.e., "off the shelf") software to determine its suitability for use in marine placer exploration applications. Various commercial software packages, each purportedly capable of making different types of statistical and/or mathematical calculations, were tested by evaluating their performance in handling geochemical data sets representative of actual marine placer locations. These data sets include the positions and results of chemical analyses of suites of sediment samples collected from areas of known or suspected marine placers along the Bering Sea coast of Alaska. The evaluation of each commercial program involved a comparison between the results obtained from using the test program

Jan 1, 1991

By J J. Culberson

The past 10 years has seen use of computers become widespread in the mining/exploration industry (including coal, precious and base metals, oil/gas and industrial minerals). This paper will concentrate on the use of computers as a tool to provide technical solutions (including data management, mine planning and operational support) to this industry rather than the use of computers to aid accounting, maintenance and inventory (æcommercialÆ) applications. This paper will review the processes and benefits of the use of computers in mining. We then review the use of technical computing locally here in New Zealand and see what business benefits local users have found from using computers in mining. We have, in research for this paper, spoken with mining software vendors from around the world to find out what is currently the æbest practiceÆ in the industry. The paper will then list what those vendors see as the ultimate improvement on the cards for the future of mining software.

Jan 1, 2000

By Om P. Garg

The purpose of this paper is: 1) To summarize the capabilities and some of the limitations of the existing mine planning software. 2) To provide some guidelines for acquiring the software. 3) To identify problems and challenges in terms of how to justify increased use of computers (particularly the 32-bit microprocessor based super micro computers), for various activities related to a mining operation No attempt has been made to review the contents of available software packages in detail. Also the scope of this paper is limited to mine planning related computer applications. Applications related to accounting, inventory control, preventive maintenance, equipment scheduling, etc. have not been covered.

Jan 1, 1983

By O. Garg

This paper summarizes the computer applications in open-pit mine planning at the Iron Ore Company of Canada (IOC). A brief history of the use of computers at IOC is given, and a description of the existing facilities is outlined. The following systems are discussed: storage and retrieval of geological data; geotechnical data analysis; long-term grade and tonnage forecasting; ore grading; and open-pit mine design. Justification for using computers in open-pit mine planning is given, and possible future areas of application are considered.

Jan 1, 1979