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By Philippe Dumont

Presentation of the project Underground civil works to be performed They include two single track running tunnels and a service tunnel of a length of fifty kilometers . Many cross adits (180 adits) : to link the tunnels (53 cross passages), to relieve air super pressure from one tunnel to the other (87 piston ducts), to install technical adits (40 electrical rooms). Two cross-overs located at one third of the whole length, allow trains to shunt from one tunnel to the other so as to ensure one way traffic in case of emergency. Pumping stations allow water to be collected at the lowest point and pumped out. 1 Main features of the tunnels 1.1 The service tunnel This 4.8 m inner diameter gallery allows During civil works - front probing operations of the geological layers encountered (front and vertical probes). - lateral soil grouting that may be necessary to facilitate the boring of the two running tunnels . During operations - Maintenance and safety vehicles traffic - Fresh air supply to running tunnels - Fire protection and drainage system - Electricity supply and control and communication. The service tunnel has been bored with a 5.72 meter external diameter Robbins TBM for the undersea section, and a MITSUBISHI TBM for the land section.

Jan 1, 1991

By D. J. McKee, D. M. Wiseman

The usefulness of simulation as a technique for metallurgical process design and optimization studies has been greatly extended over the last few years by the development of a number of general purpose simulation packages. The packages, or simulators, all have the common objective of presenting the mathematical models and simulation methods in a form which is readily usable by plant engineers and metallurgists. To date, most simulators have been concerned with steady state simulation, but packages capable of dynamic simulation are now becoming available. The paper outlines the essential features of versatile steady state and dynamic simulators. Typical applications are presented by considering examples of design and optimization studies. Limitation on the use of simulators are also presented.

Jan 1, 1991

By M. Rîsteiu

The authors aim to analyze the behavior of smart sensors using Transmission Control Protocol/Internet Protocol (TCP/IP) infrastructure in hazardous applications, because of their advantages regarding safety, expansion and Quality of Service (QoS). Initially, some constraints are discussed for these applications. Then, the possibility is analyzed of using 2.4 GHz TCP/IP based transmission for sending data out of an industrial area. In this setup the authors evaluated the round-trip implementation (which requires a database of packet lengths), related to the delay introduced by the radio transmission algorithms from 802.15.4, and 802.11d/g protocols. Tuning results of different varying time-delays were compared to the constant delay cases from the literature (Deák, 2003; Lincoln, 2003). Both the hardware and software setups are implemented. Based on TinyOS specific software for hardware checking/ initiating communication/ starting/ closing measurements the authors have developed separate/combined procedures for testing the integrated devices. Measured time delay is presented and analyzed, for both beaconed and non-beaconed 802.15.4 transmission, with power optimization criteria. By testing two different implementations (Zhang et al., 2001), (ATmega256 RZAV - 256KB flash memory, the CC2420 IEEE 802.15.4 and ZigBee-compliant RF transceiver core - 128KB flash memory) the authors have found some time delay variations as a result of local processing by the ZigBee controller with an amount of flash memory. The work is also focused on adapting industrial measuring standard systems to the smart sensors, but not only through the 4-20 mA standard.

Jan 1, 2008

By T. Stuczynski

In the past ten years about 3000 wastewater treatment plants have been built in Poland. The result of this development has been a massive increase in overall sludge production. According to data supplied by the Ministry of Environmental Protection, 400,000 dry tons of sludge are generated every year in Poland (Koblak-Kalinska 1996). Still it is difficult to estimate the amount of sludge, which is used in agriculture or for reclamation purposes. However, it can be assumed that this comes to no more than 10 percent of all sludge produced in Poland on a yearly basis. Thus it became obvious that an urgent solution to this problem was needed. Local authorities in Silesia realized in the early 90?s that a demonstration was necessary to encourage the proper utilization of sludge. This was the basis for establishing the Biosolids Subpart of the Silesia Project, which addressed the use of biosolids in the reclamation of mining and smelting dumps (Stuczynski et al. 1996). Metal waste sites themselves are known to contain more than 87 million tons of waste (Pistelok et al. 1995). Each year this amount increases by approximately 400,000 tons. We realized that a simple solution for stabilizing these sites would be to cover them with vegetation in order to reduce leaching of toxic elements, as well as to keep metallic fugitive dust from entering the environment. The reclamation of smelter waste sites, which was carried out within the framework of the Silesia Project was a joint effort of local government, industry and international research institutions/agencies, including the US Environmental Protection Agency (EPA), the Center for Research and Control of the Environment (OBIKS), Virginia Polytechnic Institute and IUNG. One of the goals was to evaluate the possibility of adapting the rules of sludge management currently used in the United States to conditions commonly found here in industrial regions of Poland. However, the main objective of the Silesia Project was the development of guidelines concerning all aspects of sludge use for the reclamation of degraded lands and waste sites. Biological aspects related to reclamation of metal waste with the use of biosolids will be discussed in this paper.

Jan 1, 2002

By Lothar Anheuser

Theoretical research, laboratory tests and practical experience confirm the possibility to stabilise the excavated tunnel front by suitably composed slurries even in coarse ground with extremely high permeability. The fluid assures dependable repartition of the pressure, low torque of the cutting wheel and small perturbances of the original ground structure. Very easy access to the front, for tool repair or removal of obstacles, are other features of the WF-Hydroshield concept. For soft ground, the Hydrojet (excavation by immersed slurry jets) permits still further improvements. Field experiences in very mixed face conditions are related. Measured soil subsidences in homogeneous, loose sands above Hydroshield-driven tunnels are compared to calculated values. Dependable shield tail seals, which are a necessary condition for work without compressed air in the tunnel, and an original repair kit are presented. The aim to liberate shield driving from hazards of narrowly defined soil conditions and to broaden the range of applications led to a series of bentonite shield machines, derivated from the initial slurry type, such as Dense Mud Shield, Earth Pressure Balance Shield or shields with hard rock cutterheads. Similar to these constructions, overall stability of the front was the major concern in developing the Hydroshield. Initially, this type was designed for use in cohesionless medium to coarse sands and gravels only. The mechanism of front collapse, initiated by a local slide uncovering a limited area, which triggers a

Jan 1, 1983

By A. M. Stone

Following the conceptual idea of a Continuous Elution Process early in 1982, the system was successfully pilot plant tested at Western Mining's Kambalda gold plant in December 1982. As a consequence of these tests the Ok Tedi elution ciruit design was changed from batch operation to continuous operation resulting in a reduction in the number of similarly sized elution columns from five operating with one standby to one operating with one standby and halving the process steam requirements. In addition to providing significant capital and operating cost savings the continuous process was simpler to operate than the batch process.

Jan 1, 1989

By Hassan Madani

Kushk lead-zinc mine is located in central part of IRAN. The mine is owned by Bafgh Mines Co., which is a nationalized company. Exploration results show that ore occurs in the area that extends for 800m length and 180m depth. The approved, probable and possible reserves of the mine is 900,000 tons, 1,120,000, tons and 1,450,000 tons respectively with average grade of 17.7% zinc and 4.3% lead. The total annual output of the mine all was by underground mining, is in the order of 100. 000 tons. The main entry to the mine is via an inclined shaft with a cross-sectional arp of 8 m2, length of 263m which dips at 20°. The ore is mined mostly by sublevel stopinq method. The major difficulty in ventilating the mine was that related to spontaneous combustion of pyrite, which was more serious in some parts of the mine than others. In order to reduce this risk, a new ventilation system for the mine was designed, using 4 exhusting fans.

Jan 1, 1991

By L. Adler

Determining whether a railroad locomotive will skid under varying conditions is a fairly routine, pervasive problem. However, some of the equations provided are wrong, others are at best murky. All require correction or clarification. Skidding during heavy braking is a crucial safety problem, possibly resulting in loss of control and collision. It can also be an economic detriment, ruining wheels and tracks and, by inhibiting acceleration, causing reduced full-speed times. While skidding is less likely for rubber-tired equipment, a comparable problem exists for tractor-trailers operating on poor surfaces. The primary reference is to the SME Mining Engineering Handbook (pp. 14-11, Eqs. 7 and 8), which is taken as authoritative and normative (Brantner, 1973). Fundamentally, the physical weight of the locomotive can never be negative (-). However, based on this reference it can be negative on adverse grades, during braking (Eq. 7), and on favorable grades, whether accelerating or braking (Eq. 8). Additionally, it should be noted that the term rW should be Rw. To avoid having the locomotive weight turn out negative, "absolute value" brackets must enclose the right-hand expression of both equations. Also, the weight of locomotive can be greater than the right-hand side value introducing the common "greater than or equal to" symbol (>_). While these alterations are easy to make, the use of the algebraic sign associated with each term is still confusing, as

Jan 1, 1991

By Dan B. Kivari

A key operation of any milling circuit is grinding. Over the last two decades, large diameter semiautogenous grinding (SAG) mills have become the preferred primary grinding mills. The drive systems became more complex as the size of the mills became larger, during which time operating and design experience for SAG mill accumulated. Considerable reliance is now placed in power electronics to provide flexibility in SAG mill operation to meet the demands of lower operating costs. Most earlier SAG mills were designed to operate at fixed speeds. Present day SAG mills can operate at a fixed speed or variable speed through the use of an ac synchronous motor or dc motor. This flexibility, however, comes with an increase in capital and operating costs. Since the capital and operating costs of a project directly affect the project's rate of return, the selection of a SAG mill and its drive system should depend, in part, on the impact that the extra cost makes on the project. This impact can be measured by performing an economic analysis based on net present cost (NPC) calculations. Although the NPC calculation is an important factor in the grinding mill selection, other factors, such as reliability of mill drives and power source, are important elements in the decision making process. This article examines how the NPC calculation, plus reliability and power source, influence SAG mill selection.

Jan 1, 1992

By J. E. Wennen

Screens serve several important functions in CIL and CIP processes for gold extraction. One important screen application known as interstage screening allows slurry to be continuously transfered through a series of CIL or CIP tanks while retaining activated carbon in the tank. In some cases, this has been accomplished by using airlifts to carry slurry containing activated carbon to an external screen which separates carbon as oversize and returns it to the tank by gravity. The undersize slurry advances to the subsequent tank. More recently this has been accomplished using launder screens and Kambalda type screens. These are essentially static screens that rely on air blasts or mechanical sweepers to clear carbon away from the screen surfaces.

Jan 1, 1998

Information Technology has addressed those problems unique to senior management in the mineral industry. In general, these problems are those concerned with decision-making. Peter Drucker in his discussion of making effective decisions identifies five phases: (1) define the problem, (2) analyze the problem, (3) develop alternate solutions, (4) decide the best solution, and (5) convert the decision into effective action. The scope of the chapter by Guernsey addresses the first three phases which provide input to the decision-maker. The decisions to be made relate, in most instances, to the economics related to a mineral property or process. Computer models have been designed to generate these economic and financial evaluations. No one model is appropriate to the solution of all management's problems. In this chapter several applications are identified and summarized; a model for the economic evaluation of a mineral property is described in greater detail. The implementation of such models is dependent on the unique needs of management.

Jan 1, 1979

By Robert McEwen

Conveyor equipment beyond its prime chronically suffers from a lack of understanding in today's plant environment regularly delivers more material than original designers ever expected. A case in point is a belt conveyor in a major hard rock mine/milling operation asking to bring the unit up to current standards while eliminating spillage and reducing airborne dust. The challenge was to keep the system going by revamping the system while keeping the same footprint and allowing for higher production rate. Thirty years of daily maintenance and dust collection costs have virtually disappeared by the end of this challenging upgrade.

Jan 1, 2008

The stability of mine roofs in permafrost zones is determined mainly by temperature and ice content. The deformation resulting from creep and temperature-dependent physical properties of frozen rock mass is the dominant component of total deformation. Roof bolts can consolidate the roof and control its deformation. In this paper, a finite-element model, for the analysis of the effects of roof bolting in a frozen rock mass is presented. The model includes the variables normally encountered when analyzing the effects of roof bolting in rocks. It also accounts for properties unique to frozen rock mass: creep deformation and the change in Young's modulus with changing temperature. The model shows that, as bolt spacing decreases, there is a trade-off between increased roof stability from increased mechanical support and decreased stability from increased conduction of heat into the frozen roof. This result was expected and shows that, for a given set of rock-mass conditions, including ice content, temperature, particle size, etc., there is an optimum bolt length and bolt density for minimum roof deflection.

Jan 1, 1997

By Jeffrey B. Smith

Introduction The gas shortage is going to be with us for some time to come. If we can set aside political and industry rhetoric (along with subjective personal opinions), we still are confronted by two serious "facts of life": (1) for almost a decade the U.S. has been consuming natural gas at a greater rate than we have been finding new reserves; and (2) there is a finite amount of natural gas present within the earth&apos;s crust. Much of the known and easily exploitable sources of gas (the so-called "conventional" sources, such as the high permeability sand reservoirs of the Tertiary sequence along the Gulf Coast) already have been developed; their production is declining rapidly. The total producible reserves from conventional gas reservoirs amount to only 216 Tcf, less than an 11-year supply. However, several large potential resources of natural gas remain to be developed. These "unconventional sources" have low permeability and/or peculiar producing characteristics. The DOE program for development of these unconventional sources of gas is called the enhanced gas recovery (EGR) program. The primary goal of this program is to provide a data base of resource characterization and production technology that will lead to commercial development. DOE will encourage and support industry participation in developing and demonstrating technologies needed to reach this goal. Unconventional Resources Four major unconventional resources of gas have a high potential for commercial development. There are other unconventional sources (such as gas hydrates) that are too poorly defined to warrant a major development thrust at this time. The four unconventional sources of gas currently included in the EGR program are: 1. The carbonaceous shales of Devonian age in the Appalachian, Illinois, and Michigan sedimentary basins are the targets of the Eastern Gas Shales Project (EGSP). 2. The low permeability, low porosity so-called "tight" gas sandstones of the Upper Cretaceous/Lower Tertiary in the Rocky Mountain areas constitute the resource target for the Western Gas Sands Project (WGSP). 3. The free methane trapped in coal beds of both the eastern and western U. S. constitute the Methane from Coal Beds Project (MCBP). 4. The abnormally high pressured, high-temperature saltwater aquifers of the Texas-Louisiana gulf coast are targets of the Geopressured Aquifer Project (GPAP). Basic implementation strategy for these EGR projects involve (1) assessing and characterizing the resource potential of the resource; (2) conducting cost-shared field testing with industry to improve, develop, and demonstrate various stimulation and production technologies; (3) coordinating EGR activities within DOE and with other federal agencies (such as the Bureau of Mines) to minimize duplication; and (4) aiming all projects toward commercial development of the gas resources. EGSP What type of "geological animal" is the EGSP dealing with? While gas undeniably is related to the occurrence of natural fracture systems within the shale, the overall producing mechanism and precise location of fractured, gas-bearing locales within each basin is still poorly understood. By developing reliable resource characterization techniques and applying effective stimulation technologies we intend to elevate the Devonian shale from the status of a potential gas resource to that of a proven gas reserve. Once we have done this the private sector can take over the large-scale commercial development of the Devonian shale gas resource. WGSP The second largest project (both in terms of complexity and level of funding) is the WGSP. The primary targets for this project are the low permeability (< 1 md) gas sandstones of the Piceance, Uintah, and Greater Green River basins and the Northern Great Plains Province. Project success in these four primary geologic locales will permit investigating additional low permeability sandstones in 16 other sedimentary basins. It appears that the only practical means of increasing permeability and resultant flow rates from these sandstones lies in the use of massive hydraulic fracturing techniques. Unfortunately, it is still too early to design such jobs with predictable results. MCBP The MCBP is to be involved in producing and utilizing methane derived from coal beds. The coal, like portions of the Devonian shale, is impermeable, highly fractured (termed "cleat" by

Jan 9, 1980

By K. Valta

This paper presents an approach for developing a Sustainable Development Indicators (SDIs) framework tailored to the Greek Industrial Minerals sector, due to its importance for the national economy. To achieve this goal, an overview of the Greek mining and minerals, and especially the Industrial Minerals sector, from a technological and a financial perspective, is presented. In addition, a brief description of the global initiatives to this direction is given. The proposed indicators are based on those presented in 2006 by the Greek Mining Enterprises Association (GMEA) adjusted for the sector of industrial minerals by taking into account economic, environmental and social issues, known as the Triple Bottom Line (TBL) approach.

Jan 1, 2007

By A. Shah, L. W. Saperstein, M. C. Radomsky, D. L. Passmore

The development of microcomputer software that provides an analysis of pit-specific accident and production data for the mining industry is seen as a vital component in a total loss-control system. The Mine Injury Reporting System (MIRS) allows users to access accident and production data prepared by the Health and Safety Technology Center of the Mine Safety and Health Administration of the US Department of Labor for any particular state and to generate a simple, yet informative, report.

Jan 1, 1990

By 000-000-604

HISTORIACAL INTRODUCTION Mineral processing has three principle branches, to quote Taggart, "Ore Dressing, which comprises the methods of separation of solids in inorganic crude by means which do not affect substantial chemical change; Extractive Metallurgy, which utilizes chemical reactions for separations of constituents from solids in inorganic crude; and, Fuel Technology, which employs both physical and chemical methods for separating and rearrangement of liquid gaseous and solid components in crude oil and natural gas, tar sands, shale oil, or coal." The scope of this handbook covers the first two classifications, that is, "ore dressing" and "extractive metallurgy," which have been combined in one term: "mineral processing." For a brief history of the development of mineral processing, one could well refer to the Introduction, Sec. I of the Handbook of Mineral Dressing by Taggart, Froth Flotation, Principles of Mineral Dressing by Gaudin, and the original Richard&apos;s Ore Dressing, volume No. 1, first published in 1903-1905. In these references and the references given in them a coverage of the history of "ore dressing" can be found and studied at the reader&apos;s leisure. For the history of extractive metallurgy as well as ore dressing, the bibliography in General References, taken from a History of Ex¬tractive Metallurgy by F. Habashi, will give a good background for those who are interested in more detail on the history of metallurgy in general. Mineral processing covers a very wide field as is illustrated by the topics discussed in Part II of this handbook and dates back to the early history of man which started with the production and use of native minerals such as gold, silver, copper, mercury, and meteoric iron which were washed or picked from deposits on the surface of the earth and worked because of their malleability. Later, melting was discovered and then it was possible to cast objects of these metals, excluding mercury. The discovery of a method for reducing the metal¬lic oxide probably was developed from melting fragments of oxides or roasted sulfides with charcoal, so that the native metal could be produced in simple blast furnaces such as are used today in rural parts of Spain, China, and elsewhere. Eventually, it was learned that iron could be readily worked when hot, which resulted in its replacing bronze for tools, weapons, and cutlery. Carbon dating and correlation with the Brittle Cone pine has

Jan 1, 1985

By James W. Babcock

Introduction Geologic ore deposit models are key to any exploration program. In the search for ore deposits, the geologist first tries to understand the genesis of known ore bodies. During reconnaissance and evaluation of a prospect, a valid exploration model of a known ore body can help the explorationist focus on critical geologic attributes of the target area. Exploration models can conserve exploration funds that might otherwise be spent collecting data not critical to delineating an ore body. This article examines the benefits of using models, factors to be considered in developing models, and examples of the way recent models have evolved. New exploration concepts and techniques are developed in response to increased competition in the mining industry. New techniques can give an exploration group a slight edge that may translate into a discovery. Mine geology staffs may find previously unlooked for extensions to the ore body by applying new genetic concepts. When all appropriate techniques are applied to exploration and mining efforts, greater efficiency and increased profits may result. Before the 1950s, scientists speculated on the genesis of ore deposits and other natural phenomena. But they presented their results as if universal and final, even though they applied to only a few deposits. Because it did not provide sufficient criteria to distinguish the genetic processes, the classic conflict between hydrothermalists, epitomized by Lindgren, and nonhydrothermalists did not help the minerals explorationist much. Important information about individual ore deposits, such as age of the host rocks and mineralization, composition of the mineralizing fluids, and separation of mineralizing and nonmineralizing events in the paragenetic sequence, could not be gathered with past equipment and methods. But these early concepts of ore genesis contained excellent empirical observations, perhaps the most useful parts of these hypotheses. Through the years, prospectors have found most of the ore deposits in the world using direct observations and their collective empirical wisdom - an empirical model. The geologist&apos;s contribution becomes increasingly important after the more obvious surficial ore deposits have been discovered. In Europe and North America that time has arrived. With the introduction of sophisticated equipment and matching techniques in the 1950s in geochronology, geochemistry, geophysics, remote sensing, and computers, many previously equivocal genetic questions can be resolved. This proliferation of highly technical data has allowed the construction of many well-founded genetic models.

Jan 12, 1984

By Jerry C. Tien

This paper investigated the airflow pattern in the working face area during a cross-cut development. The study used a 10:l scale face model and a mock continuous miner. Results showed that keeping up the line curtain is essential in order to avoid recirculation and to control respirable dust and methane, in the face area.

Jan 1, 1989

By H. Lyn Bourne

This is the eighth annual tabulation of royalty information. Again this year, some of the older information has been deleted to make room for nearly 30 new entries. Several articles and publications have appeared recently that relate to mineral royalty or mineral valuation. R. B. Parsons wrote "Mining agreements, royalties and profits" (CIM Bulletin, November 1988). He distinguished between net smelter return (NSR) and net profit interest (NPI). Parsons used examples to show the difference between these royalty payment methods. Mining Engineering (January 1990) carried an article by H. V. S. Tingley entitled "Using business due diligence to help evaluate mineral deposits." The article identifies some factors that must be examined during mergers or acquisitions in the mining industry. Since each mining operation is unique, each has risks and opportunities that need recognition and evaluation. The author suggests that a team is necessary for a proper evaluation because no one person has expertise in all of the factors that must be examined. Also in January&apos;s Mining Engineering was "Limestone mining: Reserves and valuation," by B. C. Lewis and R. P. Moran. They presented two case studies of valuation of limestone reserves. One was a 109-hm2 (270-acre) parcel in West Virginia and the other a 121-hm2 (300-acre) tract in Alabama. The authors discussed risk, discount rates, and royalty methods as financial parameters in valuation of limestone reserves. Two papers were presented at the SME meeting in Las Vegas, NV in 1989 that bear mention. J.G. Russell&apos;s talk was entitled "Valuation of industrial

Jan 1, 1990