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By Lawrence D. Ramspott

A test of retrievable geologic storage of spent fuel assemblies from an operating commercial nuclear reactor is underway at the Nevada Test Site (NTS) of the U.S. Department of Energy his generic test is located 420 m below the surface in the Climax granitic stock. Eleven canisters of spent fuel approximately 2.5 years out of reactor core (about 1.6 kW/canister thermal output) were emplaced in a storage drift along with 6 electrical simulator canisters. Two adjacent drifts contain electrical heaters, which are operated to simulate within the test array the thermal field of a large repository. Fuel was loaded during April-May 1980 and initial results of the test will be presented.

Jan 1, 1981

By P. R. Taylor

The ability to process complex precious metal sulfide concentrates containing antimony and arsenic in an economic and environmentally safe manner is an important problem facing the mining industry in the United States. Preliminary experiments have been performed to evaluate the possibility of treating a complex sulfide concentrate to recover antimony and precious metals while fixing the arsenic and sulfur as calcium arsenate and calcium sulfate. The process involves: • the oxidation of the antimony and arsenic minerals in the presence of soda ash (to collect the sulfur dioxide and to keep the antimony and arsenic from forming volatile compounds), •the selective leaching of the arsenic from the roast calcine with a heated caustic solution, •the precipitation of the arsenic and sulfate with calcium hydroxide and/or calcium chloride, •the reduction of the residual antimony (collecting the precious metals), •fuming of the metal to form a marketable antimony oxide, and •crucible reduction of the residue to obtain a gold and silver dore. Batch experiments, using synthetic concentrates of stibnite and arsenopyrite, were performed to evaluate the first stage of this process. Variables studied included mixture weight fractions, temperature, gas flow rate, oxygen partial pressure, and time. All of the off gas dust and sulfur containing gases were collected and analyzed. The roast solid residues were subjected to arsenic leach tests, and the leach solutions were subjected to arsenic and sulfate precipitation tests. Introduction The ability to treat a precious metal ore containing appreciable amounts of antimony and arsenic is dependent upon the characteristics of the ore. For some ores, selective flotation can be used to separate the antimony and arsenic minerals, which are then treated separately. Unfortunately, many ores are not treatable in this way, and the concentrates obtained may contain appreciable contamination (which limits the ability to make acceptable grade antimony products). If we consider the added value of the precious metals in the concentrate, then it is worthwhile to evaluate the potential for new methods to treat these types of concentrates. In addition, the environmental difficulties associated with arsenic disposal must be taken into account in any proposed process. If there is appreciable arsenic present, then it must be either recovered as a marketable product or placed in an insoluble form. The problem addressed in this research program has become increasingly important as the precious metals mining industry is encountering more ores of this type. A large deposit of this type exists in Idaho where the antimony occurs primarily as stibnite, with minor amounts of kermesite and tetrahedrite (Cooper, 1951). The gold appears in association with arsenopyrite with minor amounts of other arsenic minerals. Flotation has been used to obtain an antimony concentrate. The concentrate, however, is contaminated with appreciable amounts of arsenic and also contains precious metals. If the ore or concentrate contains appreciable amounts of base metals, then the recovery process becomes much more difficult. There are a number of other known deposits of this type in Alaska, Canada, Montana and elsewhere. The objective of this research program was to develop a fundamental understanding of the oxidation and leaching chemistry of the arsenic and antimony minerals so that technology may be developed to treat these ores in an economic and environmentally safe manner. Wendt (1949) and Koster and Royer (1940) discussed the possibilities of oxidative roasting of stibnite concentrates containing arsenic. Wendt describes a process used at a smelter in Czechoslovakia (in the 1930s) where roasting was carried out in rotary furnaces at 723° K (500° C). Most of the arsenic was removed as fume, as well as 25% of the antimony. No sulfur dioxide containment was described. The oxide fume from the furnace went to a heated caustic water leach, where the arsenic was preferentially dissolved and then precipitated with calcium chloride as calcium arsenate following solid-liquid separation. The antimony oxide was sold, and the solid oxide discharge from the rotary furnace was sent to a blast furnace where the antimony metal, containing the precious metals, was recovered. The metal was fumed to obtain antimony oxide, and the precious metals were left in the residue and collected with copper. The copper

Jan 1, 1994

By A. M. Edwards

In many ways a government could be regarded as a macro business enterprise. Its shareholders are its peoples, the productivity of the nation depends on them, and, indeed, the profits or losses of a nation's balance sheet can be linked to the surplus or deficit in its balance of payments. International loans need to be repaid, and in most developing nations the noose is tied so tightly that one wonders if such debts will ever be repaid. In their endeavour to meet such obligations, their currencies may be devalued [sometimes in frightening proportions], in the hope of boosting the export potential. However, this is a vicious circle, since exports will not be achievable unless sufficient technical expertise and infrastructure exist to address the opportunities which may have been created through devaluation. Many of the poorer countries have exportable resources of minerals, which are supplied on the international market. This may be the good news, but, unhappily, steps were seldom taken to enhance the value of the mineral products through further beneficiation and the production of high-value sophisticated products. That is where the vicious circle comes in: inadequate infrastructure is created, competent and well-trained manpower is not generated, and the result has inevitably been that the GDP slips backwards, and the nation becomes progressively impoverished. To exacerbate the problem, it is unfortunate that the more impoverished a nation becomes, the greater is its birthrate, and hence the greater the need to create wealth at the very time that the nation is becoming poorer and poorer. Within this scenario, one may well reflect that this is exactly what nations on the African Continent are experiencing, namely exploding populations, although most of the poorest nations in the world are found on this continent. Yet they often possess a superior mineral production potential. Africa still suffers from what may be called the colonial influence, in that the developed world has regarded this continent as a source of raw materials to feed its own factories. The colonial powers gave only secondary attention to developing the nation's peoples and its infrastructure, such as railways, roads, harbours, and other services. These problems all naturally fall within the ambit of government interest, and it is therefore obvious that the state should play a dominant role in addressing them. The reasons for governmental involvement in mineral-related research and development differ considerably, depending on the state of industrial development of that country. Thus, in the highly industrialised world, government's interest will lie mostly in the fields of strategic minerals, which may not be economically exploitable. An example would be the exploitation of American low-grade chromites during the Second World War, or minerals which need to be imported from unfriendly or unreliable sources, such that disruption would not be in the national interest. Colonial powers like the United Kingdom and France established R&D facilities to assist, inter alia, in the exploitation of mineral resources in their colonies. The approach of developing countries would differ from that of the industrialised nations, in that their primary quest would be to promote, support and encourage the development of infrastructure, and the establishment of major industries in order to create and provide employment opportunities, as well as to support small operators who cannot afford to undertake their own research and development. On the debit side, it is a sad fact that, however good their intentions may be, underdeveloped countries are invariably unable to provide the requisite financial support to sustain their own research-and-development laboratories. In a high-tech world, the cost of sophisticated equipment is steep and cannot be afforded. Again, the proverbial vicious circle comes into play. The competent researchers find themselves without rewarding employment and would therefore shun such institutions. Recent trends in the developed world have been to privatise research-and-development institutions, the argument being that they should draw closer to the industry they serve, and that the provision of taxpayers' money for strategic purposes is no longer as important as it may have been once. Complete state withdrawal has had its negative effect in that long-range, high-calibre research has tended to be replaced by short-term problem-solving projects. Industries engaged in the minerals business differ somewhat from major ones, like motor, computer or pharmaceutical industries, which are large enough to support their own internal research and development, and whose work is highly confidential, so that any leakage could have disastrous consequences. Furthermore, private companies are answerable to their shareholders and costly long-range, 'blue-sky' research would be difficult to justify. Since mineral research has become of lesser importance in the sophisticated First World, this trend has persisted. On the positive side, R&D institutions which are totally financed by government, suffer because they tend to forget the reason for their existence. They have often become a form of auxiliary to an academic institution where higher degrees are collected by scientific boffins who, in their quest for academic excellence, tend to disregard the benefits that industry may ultimately gain from this research endeavour. The trend in recent years - and South Africa is no exception - has been for the state to progressively reduce its subsidy, whilst at the same time encouraging research organisations [for their ongoing survival] to interact closely with industry, and to conduct work directly for them on a contract basis. Organisations such as CSIRO in Australia, CANMET in Canada, the USBM in the United States and Mintek in South Africa all generate income from the private sector. However, the critical fact is that the State should never withdraw

Jan 1, 1995

By A. M. Johnson

Although known primarily for native copper, the Keweenaw Peninsula of northern Michigan also has deposits of copper sulfide (chalcocite) ore. A number of small, but rich, deposits are present at relatively shallow depths near the base of a thick, steeply dipping sequence of volcanic and sedimentary rocks. Because much of the ore is fracture-controlled, the deposits appear to be ideal candidates for in-situ leaching. Fracture mapping from drill core and borehole logs coupled with borehole packer permeability tests are being applied to evaluate the suitability of the ore for in-situ leaching. A leaching scheme utilizing a bacterial-assisted ferric iron lixiviant is being tested at bench scale. A pilot scale test is being designed to evaluate the system in the field.

Jan 1, 1988

By Yukika Miyashita, Takahiro Inoue, Kenji Namikawa, Masashi Matsumoto, Junichi Koseki, Yoshihiro Terashima

"In order to construct an underground two-layer expressway branch junction structure with a height of 14.7 m and a width of 22.3 m, two shield tunnels in each layer were combined by using a non-cut-and-cover enlargement method in sedimentary soft rock. Before and during the construction work, preliminary analysis, in-situ investigations and laboratory tests were conducted to ensure the construction safety and to evaluate the deformation characteristics of sedimentary soft rock. The construction project was safely executed without any water leakage or collapse of tunnel working face. The predicted results from preliminary analysis were almost similar to the measured values. From the detailed investigation of measured results, it was confirmed that the deformation characteristic of the sedimentary soft rock was observed to a small extent as the ground deformation derived from construction work. INTRODUCTION In recent years, some newly constructed urban expressways in Japan are being planned as underground structures due to the consideration of roadside environment. The construction of such underground expressways is frequently conducted using a shield tunneling, a typical one of non-cut-and-cover methods, to prevent any adverse effect to traffic in arterial roads, operation of nearby commercial establishments, and daily lives of local residents during construction work. For underground urban expressway, the connections with existing road network on ground surface or on elevated sections are indispensable, which require the construction of an underground branch junction with large cross-section. This raises a technical difficulty regardless of the open-cut or non-open-cut construction method."

Jan 1, 2016

By F. W. Bond

Predictive ground-water modeling is currently being applied to a wide range of engineering applications. In recent years models have been used to evaluate the effect of large ground-water withdrawals on regional water supplies; subsidence associated with overpumping; siting and design studies for chemical dumps; siting and safety aspects of nuclear waste storage; and heavy metal migration from disposal sites. Similar modeling techniques could be used to analyze water-related problems in the minerals industry such as mine dewatering (both open pit and underground), environmental and pollution control, and process water supply and disposal The objective of this discussion is to describe how ground-water models are being used to assist in the solution of water-related problems outside the industry and to extrapolate that use to mining problems.

Jan 1, 1980

By R. J. Sweigard

Stabilization of slopes on abandoned mine land (AML) invariably involves some channelization to control surface drainage. Typically, these channels are lined with riprap or gabions, depending on gradient and expected flow rate. The conventional treatments pose a problem since they require frequent maintenance and replacement at times. Soil bioengineering presents an alternative to the conventional measures. In soil bioengineering, living woody plant material forms the main structural component in systems designed to prevent shallow mass slope failures, surface erosion, and channel bank erosion. An experimental application of soil bioengineering techniques was designed and implemented at an AML site in eastern Kentucky. The design consisted of live fascines and live stakes using willow branches installed with coir geotextile. Channel gradient, length, and cross-section were considered in the design.

Jan 1, 1998

By R. J. Sweigard

One of the foremost problems in reclaiming prime farmland is compaction of the subsoil which is caused by the reclamation equipment. Wheel tractor-scrapers are most commonly used to replace subsoil and have been blamed for the majority of the compaction problems. Two methods of alleviating this problem that are presently being considered are mechanical subsoil loosening machines and truck- shovel combinations for subsoil handling. A field study was conducted in which dry bulk density measurements were taken in an effort to determine the effectiveness of truck-shovel combinations and subsoil loosening equipment in reducing bulk density in comparison to typical scraper replacement.

Jan 1, 1987

By Ralph A. MacMillan

Electronic systems introduced for haulage equipment in recent years probably exceed what mine management is prepared to use. Haulpak trucks alone are equipped with General Electric's Statex III drive system controls, Detroit Diesel's DDEC, Cummins' Centry engine management system and the Haulpak Management System (HMS). The future holds promising developments of even more sophisticated electronics that will lead to unmanned truck operation and control. Trolley-assist will finally come into its own due to the importance of environmental issues, as well as the high potential for increased productivity with dramatically lowerfuel consumption. All of these high technology systems do not mean much unless they add value to mining operations. Some of the benefits that can be expected from these systems are reviewed. In the near future, haul truck control and monitoring systems will be fully linked by telemetry to a mine's dispatch system, as well as to its maintenance management information system. The manufacturer and distributor can also be kept in the communications loop, so that they can better serve customer needs. Portable computers will allow technicians to talk to machine systems to quickly locate a problem, look up service information, check what parts are required and electronically order them.

Jan 1, 1994

By A. S. C. Owili-eger

An efficient state-of-the-art dynamic model to simulate and predict the rate of water production in longwall coal mining operations was developed as a tool for mine planning purposes. The model can also provide an estimate of any potential resultant hydrogeological impacts of an operation via an array of element-specific single-valued parameters referred to as the field rating indices. The computational procedure was designed to fully exploit the benefits of hydrogeotechnology and utilize a combination of conceptual, physical, empirical, and numerical approaches to define, characterize, analyze, and evaluate flow con- trolling properties of fractured rock systems. The model presented here provides a dynamic prediction method for highly fractured flow; a practical tool in mine and water control planning; and a cost-effective means of assessing, based on the best available technology, the impacts of mining on the water resources within a mining environment to satisfy local and federal regulatory requirements. Unique features include consideration of laminar and non-darcian flow domains in double-porosity-pressure hydrogeological media.

Jan 1, 1987

"When boring a tunnel, homogeneous hard rock is the exception rather than the rule. While contractors can set goals such as meters per month and performance incentives, it is also prudent to plan for difficult ground. A properly designed tunnel boring machine (TBM) can tackle fault zones, water inflows, squeezing ground, or whatever the risk may be. The alternative is not a good one: modifying the machine in the tunnel after bad ground is encountered. Not only does this result in increased downtime, but it also needlessly exposes the crew to the tunnel conditions. In the worst case scenario, the entire operation grinds to a halt.However, an accurate GBR cannot always be obtained, particularly for mountainous, high cover tunnels in remote locations. And even with a thorough GBR, unforeseen geological events can occur. What can be done in these situations? Difficult Ground Solutions (DGS) is ground investigation system with a suite of options that can be added to a shielded hard rock machine or dual-mode, Crossover machine to better enable advance when conditions are unknown or difficult conditions are anticipated.DGS consists of a set of integrated features tailored to a specific project’s geology. The main components of the system allow for ground investigation ahead of the TBM, increased monitoring and methods to keep a machine shield from becoming stuck.In fault zones and squeezing groundIf fault zones or squeezing ground are known or suspected, or if there is even a possibility of encountering them, this can greatly affect the TBM operation. Shielded machines protect the crew from the surrounding rock, and they can bore and line a tunnel efficiently, but in fault zones and converging material their shields can be their downfall. Avoiding a stuck machine is paramount to project success. DGS employs several features to avoid the problem of a machine becoming stuck. The first of these is multi-speed cutterhead drives. These drives effectively give the machine multiple modes of operation—high speed, low torque for hard rock, and low speed, high torque for difficult ground. Designing a machine with high-torque, continuous boring capabilities allows that machine’s cutterhead to restart with break-out torque in difficult ground. The net effect is that the machine can keep boring in the event of a face collapse and can bore through fault zones and running ground where the potential for cutterhead jamming exists. Going one step further, multi-speed gearboxes give the machine the ideal earth pressure balance- (EPB-) type torque if larger sections of soft ground are anticipated.Secondly, TBMs can get through squeezing ground and faults using Continuous Shield Advance. This design utilizes a stepped shield configuration — where each successive shield is slightly smaller in diameter — to avoid becoming stuck in converging ground. External shield lubrication is an added insurance against becoming stuck, using a series of radial ports that can pump Bentonite into the annular space to act as a lubricant in squeezing material.As a last effort, if a machine has already become stuck the TBM can utilize augmented, or “super” thrust. Additional thrust jacks can be added to supply an extra boost in a short stroke, generating enough force to break loose a trapped shield."

Jan 12, 2017

By John E. Husted

Universities have education as their primary purpose. This appears to be an innocuous statement with simple meaning. In an age of conflicting semantics, however, cords and meanings are often lost or changed. The term education is often broadly expanded to encompass any form of learning process, or the accumulation of knowledge, and even to the beneficial application of knowledge to man's problems, hence one find that education in universities is not solely the formal process of texts, lectures, recitations, and testing by a batch process known as class room teaching. Despite critics of education batch is spelled with an "a", instead of an "o" - at least we hope so If one defines teaching as causing to learn, then the learning objectives may necessitate a variety of approaches within the teaching concept and research is among those favored at the graduate and some undergraduate levels. Research has been among the glamour words and certain fields such as oceanography and space science have had more than their share of glamour. Unfortunately, industrial mineral research has not had the competitive drawing power of enamoring students of the "note" generation in terms of glamorous accomplishment. Research today usually requires sophisticated equipment and such equipment is expensive, both for initial purchase and operation. Again, administrations, be they industrial, government, or academic, usually require

Jan 1, 1970

By George Weinman

GEORGE WEINMAN: Our first group leader for the discussion, "Ups and Downs of Downsizing," wishes to remain anonymous. ANONYMOUS PRESENTER: When George and Jamie asked me to do this, I thought a while about what to say and went through several variations of what I’ll present today. I came up with the title "Ups and Downs of Downsizing." A lot of downsizing has occurred in all of our industries-mining in particular. While this downsizing has gone on there's no doubt that all of us produced more and more, probably with less and less people and less and less resources. But I contend that there's also a big downside associated with this. I disagree with a point made in the keynote presentation yesterday, the point being that vendors are bringing new technology to us. I can agree that the major changes associated with equipment and similar items are being brought to us by vendors. But I do contend that there's an awful lot that's getting away from us-especially if you factor in the integrated supply or the strategic alliance or the various and sundry related purchasing techniques. I contend that we are missing a lot of, let's call it, lesser technology; not major equipment changes, but different tools, different techniques for doing things, different left-handed widgets. The integrated suppliers, to some degree, are bringing this to us; but I am concerned about the small guy who comes up with a good idea but deals through integrated suppliers rather than having direct contact with plant people. They're probably going to go somewhere else and market their wares. That's what I'm hearing from a lot of smaller vendors. I also think that we are losing a lot of our knowledge base. Every time you shrink an organization somebody leaves. The bottom line: less people. When a person leaves-and I don't care who he or she is, be it the janitor who's cleaning the bathroom, the operator, the engineer-when that person leaves there's some knowledge that goes with that per- son. And sometimes that knowledge is quite valuable. I've worked more or less at the plant "low." I can't tell you how many excellent, viable projects have come from people who said, "Look here. There's a better way of doing this." And, you know, they were right. Now, maybe they didn't have the resources or the expertise to develop these ideas into full projects, but they had that basic idea. Someone may say, "Well, if we put a no. 6 skyhook here, so we can lift this particular pump without bringing a crane from 30 miles away ...." No. 6 skyhooks are a bit expensive, but what if we put together a little structural steel here or whatnot?

Jan 1, 1998

By H. C. Morehead

The United States Cement, along with other industries, is being devastated by an unprecedented penetration of domestic markets by imported products. The overriding questions are: 1. Have foreign manufacturers improved their processes to an extent they can outperform U.S. producers in their home markets? 2. Is it gross inefficiency on the part of the U.S. producers that is allowing foreign producers to be capable of replacing a local U.S. producer in his normal home market? 3. Is there a combination of the first two questions that economically justifies this type of market overrun? The answer is a simple NO!. In a fair trade market atmosphere, U.S. producers are definitely competitive.

Jan 1, 1985

By Don Opacic

The disposal of sludges and other similar industrial wastes is a major problem. Liquid wastes from industrial operations, when treated, produce significant volumes of sludge which are difficult to dispose of, because of the chemical and physical properties of the sludge. In the mining industry sludge is produced from various water treatment operations, in particular mine drainage neutralization. Waste water from coal preparation plants also produces a sludge however the sludge is in fact a slurry containing clays, coal fines and coal impurities. In many areas the disposal of these sludges is producing a serious problem. Mine drainage sludge consists of a variety of hydrous iron oxides, usually ferric oxides, contaminated with other neutralization products such as calcium sulfate. The volume of sludge from mine water or mine

Jan 1, 1973

By S. C. Howell

The mining of taconite, to provide feed for a processing plant, requires that the flow of material continue uninterrupted. This means first, that the crude must be of a size acceptable to the primary crusher in order to reduce the delays caused by plugging the crusher with chunks. Secondly, elimination of oversize in the pit will reduce costs of all wear parts used in the mining and processing of taconite. Savings in wear parts is readily recognized in dipper teeth, bases, buckets, truck boxes, and crusher parts, both primary and secondary. During the early days of taconite mining, it was soon recognized at reserve mining company's Babbitt operations that experience in mining other ores was not always (or ?necessarily??) Applicable to excavating taconite. This was especially true in drilling and blasting. Blasting of small tonnages in single or double rows simply filled the pit with scattered chunks and provided very shallow banks for shovel loading. It also created problems for the jet piercers, since all drilling had to be performed in fractured areas. Drilling efficiency suffered and costs were extremely high. Shovel and truck efficiencies were also low and again costs were high. A high percentage of secondary breakage was required. This necessitated the use of numerous man hours to jackhammer holes in chunks, preparatory to loading and blasting. After the chunks were reduced, bull- dozer and grader hours were needed to pile the taconite for acceptable shovel loading.

Jan 1, 1968

By P. N. Eksteen, G. E. Greig

The South African mining industry currently installs about 6 km per month of plastic pipes for conveying compressed air and water. Plastic pipes have a number of desirable properties and are favoured by many mining engineers because of their low mass, which facilitates ease of erection and assembly, and their excellent corrosion resistance and durability. However, they are combustible, and if involved in an underground fire can contribute to the overall toxicity of the combustion gases emitted. Furthermore, plastic pipes have the potential to conduct a fire from one part of a mine to another, and, by so doing, exacerbate an already hazardous situation. The limitations of small scale tests and the need to establish a large facility where underground conditions could be simulated was recognized by the South African mining industry. This paper briefly describes the Industry's full scale fire test facility and presents the conclusions drawn as a result of a number of full scale combustibility tests conducted on pipes manufactured from unplasticized Poly Vinyl Chloride (uPVC) and High Density Polyethylene (HDPE). Based on these findings, some practical solutions to prevent the spread of fire along the length of pipe columns of various pipe diameters and suspension configurations are presented. Recently some new and exciting developments in the field of intumescent coatings have occurred which are proving effective in minimizing the incidence of fire underground on South African mines. The potential benefits of these coatings are briefly discussed. INTRODUCTION Plastic pipes used underground on mines are predominantly in the form of protective cladding on insulated chilled water pipes and as service pipes for the conveying of water and compressed air to the workings. Plastic pipes have found wide use in the aggressive environmental conditions encountered underground due to their favourable properties relative to steel; these include being lightweight, easily installed and virtually immune to corrosion. However, plastic pipes are inherently combustible and can contribute to the overall hazard in three ways: (i) they are easily ignitable and can provide the initial fuel for a fire. (ii) once ignited, they can propagate a fire along their length and by so doing ignite other combustibles in their path, thereby contributing significantly to the overall conflagration. (iii) they can contribute to the overall heat, smoke and toxic gas emissions from a fire. While conscious of the value of small scale fire tests, the South African mining industry recognized the need for full scale testing to determine the combustion characteristics of plastic pipes under conditions closely approximating those underground and, as a consequence, a full scale fire tunnel test facility was commissioned with the objective of being able to (a), accurately evaluate the potential hazard of the various types of the plastic pipes found in mines, (b) use this information to suggest suitable fire engineering practices to minimize the hazard and (c), to practically verify the efficacy of the practices suggested. THE FIRE TUNNEL The fire tunnel is situated on a mine in the Western Transvaal and is 40 m long with a cross section of 3 m x 3 m which is typical of many haulages currently in use in South African gold mines. The ventilation drawn through the tunnel is provided by a 110 kW centrifugal exhaust fan and air velocities can be varied from 0 to a maximum of 5,8 m/s.

Jan 1, 1993

By C. Waddell

PDMI mines five different grades of ore. Shovel operators were experiencing problems differentiating one material type from another. In 1997 PDMI decided to try GPS ore control to aid operators in identifying material boundaries. Computer generated ore control maps and GPS data defining the shovels' position is fed to a computer on board the shovel. A monitor, located near the shovel operator, displays material types, their boundaries, and the shovels' position and movement in relation to the mining face. This information has reduced errors in material identification by 50%.

Jan 1, 1998

By Charles H. McGuirk

The movement of iron ore, limestone and-coal on the great lakes involves an intricate transportation network between mine, dock, vessel, railroad and consumer. The system requires that stockpiling be performed at certain points in the pipeline because of the seasonal closing of the lakes, traditionally, this has been accomplished at origin and destination with a substantial cost. Impact to both the shipper and consumer, From the time that the raw material is removed from the ground, expeditious handling and movement to final destination is threatened by a series of potential delays. An initial movement from mine or processing plant to the upper lake port must be coordinated between rail equipment and dock facility, As each vessel is loaded, a schedule must be developed which routes the cargo to an unoccupied lower lake port. However, if the vessel is not delayed by unpredictable weather conditions on the lake, the boat may still arrive at a port congested with other vessels awaiting their turn to unload.

Jan 1, 1973

By D. H. Davidson

The basic principal in the ISL process involves the recovery of metal values by moving fluids through rock instead of moving rock. The process combines surface and sub-surface operations, with the economic performance controlled by four major factors; rates of fluid injection and production from wells; the rate of mineral solubilization; the volume of rock swept by the fluid; and the volume of solution processed through the system. This paper discusses various technical and economic parameters affecting these four factors and how they impact project costs.

Jan 1, 1985