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By M. Prasad, A. K. Majumder, T. C. Rao

The depletion of high-grade phosphate ores is bringing about a search for a suitable, economically viable technique that con process the abundant low-grade phosphate reserves. About 75% to 80% of the world's low-grade phosphate reserves are associated with carbonate gangue that is not amenable to treatment by the simple techniques of physical separation. The processing of sedimentary dolomitic/calcareousphosphate ore has numerous problems, including similar surface properties of the carbonate and phosphate. Two-stage reverse anionic flotation of carbonates (dolomite/calcite) has appeared to be a promising separation technique ,for the removal of carbonates from sedimentary rock phosphate. In reverse fatty-acid anionic flotation, the depression of phosphate mineral with orthophosphoric acid produces satisfactory results for calcareous as well as dolomitic phosphate ores from several locations of sedimentary origin.

Jan 1, 2000

By R. R. Klimpel

The efficiencies of plant-scale comminution processes are often evaluated by various indices calculated and/or measured somewhat independently of the performance of any associated downstream froth flotation processes. To compare specific comminution factors, such as energy utilization, media consumption and equipment utilization time, comparisons of comminution efficiency independent of flotation behavior are appropriate. However, as increasingly detailed plant-level information is gathered on the joint and highly interactive nature of comminution and froth flotation, it is becoming even more obvious that knowing and using simple efficiency indices are not enough. What is needed are more performance-related measures of the efficiencies of the combined size reduction froth flotation system for effective plant-level economic optimization to occur. The purpose of this paper is to present examples of some of the important interactions that influence the joint efficiencies of size reduction and froth flotation processes.

Jan 1, 1999

By Thomas J. Martin, James W. Martin, Paul F. Martin

The conveyor belt is the basic building block of a broad range of material handling applications in modern mining systems. The mining plans and site conditions dictate basic system requirements but this is only a part of total design evaluation. The total system in the typical mining situation can encompass all the activities from the excavators at the mining face to the processing plant, site loadout facilities and/or a power plant. The number of alternative configurations which must be evaluated including subsystems and components is limited only by analytical time and creativity. The constraints and issues which must be addressed continue to expand, driven by reliability, environmental impact and cost competitiveness. All of the system requirements must be translated into specifications for costing, final design and construction.

Jan 1, 1993

By A. F. Fossum, D. E. Munson

The U. S. Department of Energy is constructing and operating the Waste Isolation Pilot Plant (WIPP), a research and development facility near Carlsbad, New Mexico, to determine whether or not defense-generated high-level radioactive waste can be stored safely in bedded salt. The goal of the WIPP modeling program is to develop the capability to predict room responses from one site to another without a priori knowledge of the actual room responses. Data from one of the early WIPP excavations, called the South Drift, have already been used to form an initial evaluation of computational models for predicting room closures as a result of salt creep [Morgan et al., 19851. In that study, a significant unresolved discrepancy existed between predicted and measured room closures. It was suggested that future studies address alternate forms of the constitutive law. In this paper, an alternate form of the creep model for salt is used that is founded upon the deformation- mechanism map for the micromechanical deformation processes. This model embodies both steady-state and transient creep. Also, quasi-static plasticity is incorporated into the complete constitutive model for salt. The conclusion is drawn that the combination of the mechanistic creep model, plasticity, and flow potential can approximate the late time South Drift deformation. Further improvement of the model fit of plasticity in the future is expected to further improve the simulation.

Jan 1, 1986

By Heinz Kettling

Labor costs, which have rapidly increased in the industrial countries for several years, have forced the mining industry to develop new methods and cost saving systems. Also, because mining is basic to meeting the increasing requirements for raw materials, the mining industry is guaranteed a key position in cost cutting efforts. Although this report aims to describe major recent developments in the Federal Republic of Germany, it is restricted to a limited number of them in view of the wide variety of current innovations. The most important mining activities in West Germany are concentrated in the coal mines on the Rhine, Ruhr and Saar, in the lignite open-cast mines west of Cologne and in the potash and salt mining region in Lower Saxony and Hesse. This report will only discuss developments in the underground coal mines and the potash and salt mines, and focuses on projects of Salzgitter Maschinen and Anlagen AG (SMAG). HYDRAULIC DRILLS Drilling strata of varying strength One special difficulty faced in European coal mines is the varying of compressive strength of strata that occurs even over a few meters. The strata associated with the coal measures ranges from hard and tough sandstone or conglomerate to very soft carboniferous shale. It is often difficult to use continuous miners or roadheaders so that drifting by blasting still predominates. But the varying compressive strengths of the strata makes it difficult to choose the best method to drill the rock. For example, it is best to penetrate hard sandstone or conglomerate with heavy percussion drills. The soft carboniferous shale on the other hand, should be penetrated by high speed rotary drilling to obtain optimum performance.

Jan 1, 1979

By P. J. L. Nel

The paper describes several successful concepts used in the sinking of shafts on the Elandsrand Gold Mine. The concepts enabled the shaft sinking time to be reduced as well as the period in which development would normally take place to establish initial ore reserves.

Jan 1, 1981

By P. Hornby, S. Henley

INTRODUCTION The project described in this paper is designed to provide a standard and flexible method by which data can be exchanged among different systems and packages in common use for geo- logical modelling and mine planning, with substantial savings in ad hoc programming which is expensive and produces interface software that is difficult to maintain. Such packages include specialised applications such as Vulcan, Surpac, Datamine, and Gemcom software, and the Whittle pit optimisation programs, and more general products such as AutoCad, Microstation, and Maplnfo, and database management systems through a generic SQL interface. The data translator is built around the CSIRO Data Model and GeoEditor, and will make widely available the benefits of the Data Model by adding functionality to its implementation in an industry- standard language and style, with interfaces to important geological and mining software products used by the industry, while including also the visualisation and editing capabilities of the GeoEditor which provides the functional framework within which the Data Translator is developed. The Data Translator is intelligent in the sense that it is not a black-box solution but allows visualisation and validation of data during transfer; furthermore it provides a means for changing abstraction levels during the transfer operation. There have been few similar efforts to address this problem. It is not a problem which is likely to be solved in any general or long- term way by any individual commercial software vendor. THE CSIRO DATA MODEL A wide variety of software tools have entered the exploration and mining industries via different pathways. Examination of these pathways and the origins of the software illuminates the types of data transfer problems and difficulties which might occur in the day to day life of exploration and mining operations. In exploration, the focus is normally on a large area (>5000km2) which is explored primarily in two dimensions. For 20 exploration purposes, geographical information systems (GIs) software, image processing software, and, in some cases, 20 computer aided design (CAD) software have been employed. Typically, GIs soft- ware is used the most by lands and tenements personnel and government geological survey organisations, image processing software is used the most by geophysicists, and 20 CAD software is used the most by drafting and geology personnel. In contrast, within the mining environment, almost all activities have 3D character. In this realm, 3D CAD software and specialised mine planning and design software are important. Specialised mine planning and design software is similar to 30 CAD software, but typically has additional capabilities such as specialised modules for surveying, drill hole data operations, open pit design and optimisation, underground mine design, mining block model creation, and/or ore reserve calculations. Unfortunately, the different origins of the software in exploration and mining lead directly to problems in data exchange and the design of seamless software systems. These problems result from the different data management strategies employed by the different classes of software. In order to address these problems, CSIRO Exploration and Mining and CSIRO Division of Information Technology have been investigating the structure, character, and syntax of data and soft- ware present in computer-aided exploration and mining activities since early 1993. The goal of this effort is to 1) systematically ex- amine the breadth and depth of the data in use within exploration and mining, and to 2) promote a data organisation strategy which is broad enough and comprehensive enough to enable wiser soft- ware design and easier data transfer. In the short term a data model can be used to improve data transfer; in the longer term it is hoped that a data model framework will help object-oriented concepts to enter the next generation of geoscientific software. The data model is described in more detail by Power et al., 1995. THE DATA TRANSLATOR PROJECT The CSIRO Data Model provides a basis for a very wide range of applications in geology and mining. It has been developed over the past two years by a joint team from the Division of Exploration and Mining and the Division of Information Technology, and its principal purpose is to provide a comprehensive and self consistent model of the geometric and topological properties of geological and mining data. The project is being carried out by CSIRO with the support of Australian mining companies through AMIRA (the Australian Mining Industries Research Association). Eight companies are sup- porting the project : • North Ltd Minenco • MIM Exploration • Fractal Graphics • BHP Australia Coal • Pacific Coal • Gencor CRA Exploration The systems to be interfaced have been decided by comparing the priorities of the various sponsors, to produce a final combined priority list as follows : • Vulcan • Minescape • Micromine • Mapinfo INTRODUCTION The project described in this paper is designed to provide a standard and flexible method by which data can be exchanged among different systems and packages in common use for geo- logical modelling and mine planning, with substantial savings in ad hoc programming which is expensive and produces interface software that is difficult to maintain. Such packages include specialised applications such as Vulcan, Surpac, Datamine, and Gemcom software, and the Whittle pit optimisation programs, and more general products such as AutoCad, Microstation, and Maplnfo, and database management systems through a generic SQL interface. The data translator is built around the CSIRO Data Model and GeoEditor, and will make widely available the benefits of the Data Model by adding functionality to its implementation in an industry- standard language and style, with interfaces to important geological and mining software products used by the industry, while including also the visualisation and editing capabilities of the GeoEditor which provides the functional framework within which the Data Translator is developed. The Data Translator is intelligent in the sense that it is not a black-box solution but allows visualisation and validation of data during transfer; furthermore it provides a means for changing abstraction levels during the transfer operation. There have been few similar efforts to address this problem. It is not a problem which is likely to be solved in any general or long- term way by any individual commercial software vendor. THE CSIRO DATA MODEL A wide variety of software tools have entered the exploration and mining industries via different pathways. Examination of these pathways and the origins of the software illuminates the types of data transfer problems and difficulties which might occur in the day to day life of exploration and mining operations. In exploration, the focus is normally on a large area (>5000km2) which is explored primarily in two dimensions. For 20 exploration purposes, geographical information systems (GIs) software, image processing software, and, in some cases, 20 computer aided design (CAD) software have been employed. Typically, GIs soft- ware is used the most by lands and tenements personnel and government geological survey organisations, image processing software is used the most by geophysicists, and 20 CAD software is used the most by drafting and geology personnel. In contrast, within the mining environment, almost all activities have 3D character. In this realm, 3D CAD software and specialised mine planning and design software are important. Specialised mine planning and design software is similar to 30 CAD software, but typically has additional capabilities such as specialised modules for surveying, drill hole data operations, open pit design and optimisation, underground mine design, mining block model creation, and/or ore reserve calculations. Unfortunately, the different origins of the software in exploration and mining lead directly to problems in data exchange and the design of seamless software systems. These problems result from the different data management strategies employed by the different classes of software. In order to address these problems, CSIRO Exploration and Mining and CSIRO Division of Information Technology have been investigating the structure, character, and syntax of data and soft- ware present in computer-aided exploration and mining activities since early 1993. The goal of this effort is to 1) systematically ex- amine the breadth and depth of the data in use within exploration and mining, and to 2) promote a data organisation strategy which is broad enough and comprehensive enough to enable wiser soft- ware design and easier data transfer. In the short term a data model can be used to improve data transfer; in the longer term it is hoped that a data model framework will help object-oriented concepts to enter the next generation of geoscientific software. The data model is described in more detail by Power et al., 1995. THE DATA TRANSLATOR PROJECT The CSIRO Data Model provides a basis for a very wide range of applications in geology and mining. It has been developed over the past two years by a joint team from the Division of Exploration and Mining and the Division of Information Technology, and its principal purpose is to provide a comprehensive and self consistent model of the geometric and topological properties of geological and mining data. The project is being carried out by CSIRO with the support of Australian mining companies through AMIRA (the Australian Mining Industries Research Association). Eight companies are sup- porting the project : • North Ltd Minenco • MIM Exploration • Fractal Graphics • BHP Australia Coal • Pacific Coal • Gencor CRA Exploration The systems to be interfaced have been decided by comparing the priorities of the various sponsors, to produce a final combined priority list as follows : • Vulcan • Minescape • Micromine • Mapinfo • Medsystem

Jan 1, 1996

By Peter W. Harben

Once considered the dowdy country cousins of the glamorous metallics, industrial minerals are shedding their old image. They are neither common nor easy and their time has come in an age of increasing specialization. Consider that of the 45 or so industrial minerals and rocks listed in [Table 1], almost three-quarters have ten or fewer significant suppliers (i.e., those individual countries contributing 2% or more of total world production); in more than half the cases, 85% of world production is accounted for by only five countries or fewer. Curiously, even materials that appear to be virtually ubiquitous like crushed rock and common salt have significant production vacuums. For example, there is a severe lack of sound aggregates along the US Gulf Coast and common salt production on a large scale is virtually absent in central Africa. These examples all underline the obvious, but acute truism that "The single most important fact about mineral resources is that they are not distributed equally over the world" (Flawn, 1966). Just as significant today is that human resources are not distributed equally over the world, and so arise some interesting commercial incongruities. In certain regions raw materials are plentiful but consumers are not, and without a market a mineral deposit is merely a geological curiosity. Elsewhere, there may be a market but no local raw material supply. For example, despite a huge market there is no or virtually no commercial production of chromite, diamonds, and manganese in the United States and Canada, nor phosphate rock, diamonds, rutile, and zirconium minerals in western Europe. In contrast, Australia with its small domestic market is the world's largest supplier of bauxite, diamonds, ilmenite, natural and synthetic rutile, and zircon; the same is true for South Africa which is a leading producer of chromite, manganese, diamonds, andalusite, ilmenite, rutile, and zircon (Table 2). In the commercial world, Nature's uneven distribution is counterbalanced by deep sea international trade.

Jan 1, 1994

By Cynthia M. Walck, S. K. Grant, R. D. Hagni

The Post Gold deposit is located in the northern part of the Carlin trend. The mineralization at Post occurs in proximity to a Jurassic-Cretaceous composite stock. Most of the gold at Post is hosted by non-metamorphosed calcareous siltstone and highly altered diorite, adjacent to the low grade skarn. Endoskarn, exoskarn, hornfels and marble are developed outward from the intrusive. The skarn is composed dominantly of diopside, tightly intergrown with gannet, k -feldspar, and sphene. The highest grade gold values are adjacent to the skarn, which acted as a permeability barrier to fluid migration. Post is the first Carlin-type deposit at which a skarn has been recognized to play a significant role in the localization of gold.

Jan 1, 1990

By John R. Thalimer

For the past four years the U.S. Bureau of Mines has investigated the early detection of insulation failure in squirrel cage induction motors. Data modeling techniques based on values calculated from a motor's voltage and current phasors were used to produce a pair of polynomial equations that calculate a motor's insulation leakage current and power. This paper describes a prototype system using these models that monitors six motors on a continuous miner for insulation leakage in order to anticipate insulation failure. The system consists of a motor-data system for each motor on the machine, a control computer located some ' distance from the miner, and a serial bus to interconnect these items. Each motor-data system consists of an analog interface to the motor's voltages and currents, a single-board computer that reads digitized data and calculates voltage and current phasors, and a bus node that interfaces the single-board computer with the serial bus. The control computer can request and receive phasor data from any motor-data system on the bus. Using models developed at the Bureau, the control computer calculates and displays two deterioration values for each motor, one for leakage current and the other for leakage power. These values are then stored into a database from which the user can display them over time.

Jan 1, 1992

By J. Peck, M. J. Scoble, C. Hendricks

This paper is based on field studies in North American surface mines. The work involved the adaptation of microprocessor-based instrumentation to monitor various operating parameters on-board rotary blasthole drills and mining shovels. Following a review of instrumentation and monitoring methodology - drawing on experience gained under field conditions-the paper will focus on the application of monitoring technology within the framework of an Integrated Equipment Monitoring System. Such a system will permit real-time performance evaluation of key equipment involved in surface mine production. Drill performance monitoring has been demonstrated through work to date, to provide significant input into blast design, reserve estimation, mine planning and production control processes, through an improved facility for ground characterization. Monitoring excavation equipment has been proven valuable in assessing how effectively the input from drill monitored data has been used in the evolution of blast designs. This specifically refers to assessing blast efficiency through measuring associated levels of excavator performance in relation to muckpile characteristics. The medium-term goal of equipment instrumentation and monitoring has been to assist mines in optimizing the overall rock breakage and handling process. Based on the reported results, this has been accomplished. Long-term efforts now concern using a greater understanding of equipment performance and response to varying operating conditions as a foundation for the implementation of mining automation.

Jan 1, 1993

By J. M. Mutmansky

This paper outlines the results of a study of the opinions of practicing engineers concerning the value of environmental engineering courses in a mining engineering curriculum. One hundred engineers with significant experience in mining-related engineering work were carefully chosen. Of the 67 responses, about half were from mining engineers, and the other half were from environmental engineers. In this paper, the results of the survey are outlined. The number and type of courses recommended by the respondents are summarized as well as the specific topics recommended for inclusion in a mining engineering curriculum. The survey form also asked for the stages in the mine life when environmental experts were needed and the percentage of environmental engineering performed by outside experts for many mining-related environmental tasks. The results of this line of questions are provided. Finally, the paper offers a comparison of the results for environmental engineers and mining engineers and analyzes the differences.

Jan 1, 2003

By Kent S. Roessler

The Bureau of Mines is currently investigating the geophysical application of Tomography to monitor leachate during in-situ mining. Determining the location of the leachate is important for both economic and environmental reasons. By analyzing a sequence of tomographic images, we can determine where highly permeable/fractured regions are located and hence, major flow paths. Since BOMTOM (Bureau Of Mines TOMography - Tomographic Reconstruction Program), and BOMCRATR (Bureau Of Mines Curved RAy Tomography - Tomographic Reconstruction Program) are sensitive to user-selected ray path arrival times, we are also investigating the use of neural networks to automate the process of recognizing this feature. This paper presents a technique for detecting fracture zones and their orientations in a region between two boreholes, by using a motion analysis study of a sequence of tomographic images. It also addresses the need for an automated/unbiased method to pick crosshole seismic arrival times using a trained neural network. In exploration geophysics, the picking of first break arrivals represents a pattern recognition task. The neural net paradigm has proved to be a good method of solving this type of task. To pick the first arrival peak of a trace, the network is trained with a set of known (user selected) first arrival peaks by creating a binary image of a set of traces. Once trained, the neural net correctly picked first arrivals of the remaining traces in the set.

Jan 1, 1992

By J. Harrison Daniel

Increasing mechanization of underground mining operations throughout the years has reduced the dependency on large, concentrated working forces. Fewer workers in scattered locations, coupled with the versatility of diesel equipment to load and haul personnel, supplies, and mineral ore, has made diesel equipment attractive in mine feasibility and design studies. The use of the mobile equipment along with higher production or "bulk" mining methods provides for more efficient mineral extraction systems. These systems are expected to become more widespread until long-term research provides a further evolution to more complete automation of underground mining. The U.S. Department of the Interior, Bureau of Mines, has been conducting research to reduce the health and safety hazards posed by increasing use of diesel equipment and the higher power ratings being proposed. The goal is to provide for safe and efficient use of the equipment. The National Institute for Occupational Safety and Health has recommended that diesel exhaust be regarded as a potential occupational carcinogen adding importance to the Bureau's research program. The paper describes advances in engine design, the use of diesels in mining operations, and significant health and safety research accomplishments of the Bureau of Mines. These accomplishments will help assure that diesel equipment remains an option for determining the most efficient system to mine an ore body.

Jan 1, 1989

By S. C. Suboleski, J. W. Oberholzer

This paper describes research being undertaken by the Chamber of Mines Research Organization (COMRO) to assist the continuous miner operator and section foreman in the performance of their jobs. The project will initially provide visual assistance to the miner operator, and later it will semiautomate the mining (cutting) process. Using a technique known as "RF tagging," the project will also provide the section foreman with real-time or near-real-time information about the performance of the loading and hauling units. This data will allow the section foreman to quickly detect problems and take action where appropriate. The project is based upon the application of currently available technology, and in-mine testing results from the first phase are now available.

Jan 1, 1994

In 1991, most industrialized countries, except for Germany, were in a recession or a period of reduced growth. The US economy, already in recession, suffered from mounting banking system losses and the uncertainty brought about by the Persian Gulf War. However, US and worldwide minerals exploration did not collapse as it did during the mid-1980s. Even though gold and base metal prices declined, prices were still above cash costs for most operations. This allowed the continuation of established exploration programs but sharply limited new initiatives. Exploration 1990-1991 Planned worldwide 1991 exploration expenditures declined by about 8% from 1990 levels, according to a survey of 153 companies by the Metals Economic Group (MEG). Canada was the leading exploration target with 23% of the total, followed by Australia and the US (19% each), South Africa (13%), Latin America (11%) and the South Pacific (7%). The remaining 8% was split evenly between Europe and the rest of Africa. In Latin America, Mexico and Chile are the most attractive countries for exploration. Recognizing the risks involved, the industry has been cautious about ventures in the former Soviet Union. Survey results also showed that while the majors expected to maintain exploration spending, smaller firms were cutting back or actively seeking farm-outs from the majors (personal communication, M. Wegener, MEG).

Jan 1, 1992

By M. L. Smith

The U.S. Bureau of Mines Cost Estimating System (CES) has been used for prefeasibility analysis and mine cost engineering since 1978. In the past, prefeasibility analysis with CES has involved the solution of regression equations. The new generation of CES uses an object-oriented expert system in a Windows? environment. Knowledge bases are structured around generic mine models which access shared knowledge bases for system design.

Jan 1, 1994

By Gerald V. Jergensen, Edward J. Samuel

Slurry system are the principal method for storage and transportation of solids within and between concentration operations In a mineral processing plant. A slurry 1s a mixture of solid particles In water, or a chemical solution, that behaves like a liquid. The design of slurry transportation systems is generally analagous to pumping and piping water, but with a few notable exceptions: • The interaction of particle on particle affects slurry transport. • Particles often interact with the fluid, particularly when chemicals have been added to the system. • Particles have a frustrating tendency to settle from the slurry suspension, especially into locations not considered In the design. • Solids have an affinity for wetted surf aces and tend to wear them away. Slurry transportation systems Include a number of separate components, each requiring special design considerations. A systematic evaluation of each component of a slurry transfer system will help overlooking the small details that could cause operational headaches. Most slurry transport systems include: • A receiving sump or tank that provides for mixing and/or momentary storage of slurry. • A driving force.. by a pump, atmospheric pressure or gravity. • A suitable conduit for transportation.. pipes or launders. • A delivery objective.. another sump or process vessel, or distribution system to several process points. • A control strategy and design to regulate the transfer operation. The design of the slurry transportation system normally evolves through the following steps: • Finalizing the process flowsheet and establishing the weights and volumes to be handled. • Identifying and characterizing the various process fluids and slurries. • Defining critical and minimum transport velocities of fluids. • Selecting a pipe diameter (or dimensions and gradient) and

Jan 1, 1986

By K. C. Shaver

The Sloan Ranch kimberlite complex is located approximately 130 km north-northwest of Denver in the Precambrian core of the northern Colorado Front Range (Figure 1). A Devonian age for the complex is suggested by the fossil assemblages in limestone xenoliths (Chronic and others, 1969), and by paleomagnetism of the kimberlite (E. E. Larson, personal communication, 1986). The presence of diamond was first reported in rocks from the Sloan diatreme by McCallum and Mabarak (1976). Prior to this time, the distinctive- appearing host rock of the Sloan diamonds had been quarried for use as terrazzo stone; examples may be seen in the floors of the airports in Cheyenne and Laramie, Wyoming. The Minerals Division of The Superior Oil Company obtained a lease on the Sloan property in 1980. During the next four years Superior built and fine-tuned a highly efficient diamond recovery facility, explored and tested the Sloan deposit, and used Sloan as a site for testing numerous exploration techniques for future use in a continuing exploration program in the Colorado-Wyoming kimberlite province. The Sloan property was ultimately determined to be sub- economic, but the lessons learned there have been very helpful in subsequent exploration efforts.

Jan 1, 1987

By Wilson Blake

A mathematical model based on the finite element method of stress analysis has been used to describe the behavior of the western wall of the Kimbley Pit as its slope was steepened from 45 degrees to 57 degrees. Theoretical stress changes because of slope modification are slight except at the toe of the modified slope. Magnitudes of stress created are small when compared with the strength of a competent rock. Resulting displacement patterns point out the need for determining the in situ state of stress at a site prior to excavation or modification. A comparison of model results with field measurements shows that, in general, the model has described the measured behavior of the west wall of the Kimbley Pit remarkably well.

Jan 1, 1968