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By Nelson R. Shaffer

Biotechnology has become a household word of the nineties, and it is expected to become as important in the next century as the computer is in the present. Numerous books and articles portray biotechnology developments as nothing less than a scientific revolution. Almost everywhere one looks new biotechnical breakthroughs are being reported that offer almost limitless opportunities to harness the force of living things to produce materials and manipulate their properties. Biotechnology has been broadly defined as any applications of biological organisms, systems, or processes to manufacturing and service industries. This seemingly new technology is, in fact, one of mankind's oldest scientific activities (Table l), which has been recently revolutionized by techniques of genetic engineering that arose out of basic research in biology, biochemistry, genetics, and information sciences. From fields as old as agriculture and medicine to those as new as monoclonal anti-bodies, transgenic plants, or biocomputers are encompassed by biotechnology. Like most human endeavors, industrial minerals play critical roles in biotechnology. In addition biotechnology holds real potential to improve extraction and beneficiation of certain industrial minerals themselves. BIOTECHNOLOGY OVERVIEW Companies using established biotechnical techniques make up large and diverse groups such as agriculture, chemicals, and pharmaceuticals. The massive US Pharmacopia (Anon., 1990a) provides detailed specifications for minerals used in medicines. Alumina, zirconia, apatite, and bioactive glass have seen service as implant materials (Williams, 1990) and new uses for minerals in health sciences are being actively researched. Agriculture produced $361 billion worth of food and drink during 1991 in the United States; organic chemicals, pharmaceuticals, and enzymes accounted for $68, $59, and $42 billion, respectively (Anon., 1992a). It is not possible to separate the contributions of industrial minerals to biotechnical products, but they represent a very large and rapidly growing new field of uses. The new biotechnology has nearly 300 small companies, plus 15 established companies with 742 biotechnology-related firms (Dibner, 1991b). Revenues exceeded $2 billion in 1990 and are expected to grow to $50 billion by 2000 (Anon., 1992c), with worldwide sales exceeding $100 billion (Burrill and Roberts, 1992). Federal research amounted to $3.4 billion in 1990 (Anon., 1992b). The United States is the world leader in biotechnology, but other countries have large, well-funded programs. Despite debate about safety, obstacles to new biotechnology products are declining (Embers, 1992, Gibbons, 1991). Fifteen biotechnology drugs valued at $1.2 billion (Thayer, 1991a) are on the market, and more than 100 are in various stages of testing (Edington, 1992). Many diagnostic tests are also in use or development (Demain, 1983, Anon., 1992). Large scale efforts to produce or transform important chemicals are also underway (Ng et al., 1983, Hinman, 1991), and research into geologic uses of biotechnology has begun. Much has been published about microbial mining, oil recovery, desulfurization, bioremediation, and other geologic aspects of biotechnology, but this chapter is the first attempt to explore interactions of biotechnology and industrial minerals. This chapter examines uses of minerals in biotechnology; how biotechnology can be used to discover, recover, and beneficiate industrial minerals; and speculates on some potential, but as yet untried uses. Definitions What exactly does the word biotechnology mean? Bud (1989) states that the first use of the term was by Karl Ereky in 1919 to cover the interaction of biology and technology, and in 1933 the term was used in Nature. After citing seven different definitions, Smith (1988) concludes that biotechnology is a series of enabling technologies involving practical applications of organisms or their subcellular components to manufacturing and service industries or to environmental management. Walker and Cox (1988) suggest a definition of "the practical applications of biological systems to the manufacturing and service industries and to the management of the environment." Primrose (1991) says that it is "the commercial exploitation of living organisms or their components." There is essentially an older broad use of the term and a new use. The US Office of Technology Assessment (Anon., 1984) uses a broad definition that includes any technique that uses living organisms (or parts of organisms) to make or modify products, to improve plants or animals, or to develop micro-organisms for specific uses. Definitions are different, but they all have several fundamental elements that include the control, management, or manipulation of living things for commercial, industrial, or useful ends. While such a definition encompasses all of agriculture in practice the "new" biotechnology is restricted to processes involving microorganisms-plant and animal cells, or enzymes. Many consider biotechnology to be recent, but it is one of our oldest technologies as evidenced by the prehistoric origin of brewing, cheese-making, and other techniques. [Table 1] gives some of the important developments in the history of biotechnology. Smith (1988) breaks down historical developments of biotechnology into four phases: 1) prehistoric with no understanding of underlying processes; 2) nonsterile processes; 3) sterile processes after 1940; and 4) genetic and recombinant DNA technology deliberate design of special organisms or processes.

Jan 1, 1994

By J. C. Yingling, G. T. Lineberry

A control system for reducing peak loads on mine conveyor networks is proposed. The system involves continuous monitoring of flows into the conveyor network and section feeders with variable discharge capability. The control strategy uses differences in material transit times from various production units to the transfer points in the network to forecast load levels that will he intersected by the discharge of the controlled feeders over future time intervals. Feeder setpoint adjustments are made to prevent excessive peaks in the combined flows at the transfer points, while maintaining adequate feeder through flow to avoid production bottlenecks. Simulation studies suggest that the control strategy would be very effective in reducing capacity requirements of gathering belts.

Jan 1, 1993

By Wayne A. Sadik

The mine ventilation system of the Henderson Mine provides a case study of designing and maintaining high-quality respirable air in a large underground mine with over 200 units of diesel-powered equipment. This system was designed with concern for minimizing exposure to personnel of siliceous dust, diesel exhaust, smoke, and potential fire hazards while optimizing general environmental air quality throughout the multilevel/multiheading operation. As a relatively new operation, the Henderson Mine incorporates a modern ventilating plant and mine de- sign as well as state-of-the-art technology where appropriate. Two main ventilation shafts approximately 2,300 ft (701 m) in depth (one intake, one exhaust) will handle 1.8 million cfm (850 m3/s) of air circulated throughout 60 miles (97 km) of drifting, providing the ventilation requirements for more than 25,000 diesel horsepower (18,642 kw) underground.

Jan 1, 1980

By K. N. Han

The adsorption of gold onto activated carbon in iodide solutions was studied. The adsorption rates were determined as a function of temperature, salt concentration and pH, as well as activated carbon concentration. A kinetic model was developed for the adsorption. The adsorption rate was believed to be controlled by a combined mechanism of film diffusion and pore diffusion with the film diffusion having the most significant effect. Experimental findings were in good agreement with the model developed. The apparent activation energy was found to be 14.9 kJ/mol.

Jan 1, 1995

By M. E. Orman

Many factors must be considered when designing a heap leach pad. Geotechnical properties of the ore, can and will affect how well an ore leaches, the solution recovery, stability of the heap, and settlement. As a heap is stacked some of these properties will change due to the increased load. In order to properly design a heap these properties should be determined beforehand so that the heap performs as intended.

Jan 1, 1997

By Lars A. Stålberg

"This paper will touch several of the topics covered by SDIMI 2005, including,• Sustainability indicators for the minerals industry, • Best practice of sustainable development in the minerals industry, • Social contributions,The complex issues of a company’s "sphere of influence" and "complicity" are important to every discussion of business and Human Rights. The paper will argue that to protect and promote Human Rights needs to be regarded as an integral part of sustainable development policies for the minerals industry. This implies a need for explicit inclusion of Human Rights indicators among the indicators to be applied by the minerals industry."

Jan 1, 2005

By K. A. Natarajan, M. K. Yelloji Rao

Significance of grinding media wear and its effect on chalcopyrite flotation are discussed. Laboratory marked ball wear tests were conducted grinding chalcopyrite ore and quartzite dry, wet, and with collector added during grinding. The effects of oxygen and nitrogen on ball wear were evaluated by the addition of chalcopyrite mineral while grinding quartzite. The effect of dry and wet grinding on chalcopyrite flotation was also studied. Results show abrasive wear is greater in quartzite grinding than in grinding chalcopyrite. Oxygen increases the corrosive wear of high carbon low alloy steel balls in the presence of chalcopyrite ore. Chalcopyrite flotation was retarded due to wet grinding in the presence of oxygen. Though collector reagent increased the media wear, it improved the flotation of chalcopyrite. Probable electrochemical reactions encountered in a grinding mill are outlined.

Jan 1, 1991

By Paul E. Scheerer

Synthetically produced magnesium hydroxide serves as the precursor for much of the magnesium oxide produced in the world today. Magnesium oxide, in a variety of physical and chemically reactive forms, is a very important commodity. It is used as the main component in refractories employed in steelmaking furnaces and in many base metal refining furnaces. In the chemical industry, it serves as a raw material in the production of epsom salts, rayon acetate, oxychloride and oxysulfate cements and magnesium sulfonates. It is a minor component in fertilizers and animal feeds. It serves as the starting material for producing fused magnesia, used as an electrical insulator in electric heating elements. It is employed in the magnesium sulfite process for pulp digestion in the paper industry. Additional uses are in SO2 scrubbers, as a neutralizing agent in the tanning industry and as a component in rubber compounding. Magnesium oxide is produced not only from synthetically produced magnesium hydroxide. It is produced from natural magnesites, natural brucites, and natural and synthetic hydro-magnesites. Synthetic magnesium hydroxide, as a starting material provides more control of the chemical purity and chemical reactivity of resulting magnesium oxide products because of the uniform nature, chemical and physical, of the hydroxide that can be produced. Synthetic magnesium hydroxide is produced by precipitation of Mg (OH)2 from magnesium chloride bearing seawater or natural brines through the use of a base such as Ca(OH)2 or NaOH.

Jan 1, 1978

By Ricardo D. Presnell, Erich U. Petersen, William J. Tafuri, Donald M. Hausen, Russell C. Babcock, William L. Gunter, Thomas R. Gibson, Douglas N. Halbe, Jay W. Hammitt

The Barneys Canyon orebody is a sediment-hosted disseminated gold deposit located 8 km (5 miles) north of the Bingham Canyon porphyry copper mine. Mineable oxide reserves are 8.6 million tonnes (9.5 million short tons) grading 1.64 g/tonne (0.048 oz/ton) gold. Host lithologies are carbonates and siliciclastics of the Park City and Kirkman-Diamond Creek Formations of Lower Permian age. Gold distributions are controlled by favorable stratigraphic units and associated alteration, and structures. Dominant alteration is decalcification and bleaching of carbonates, and argillization and bleaching of sandstones. Gold to silver ratios are greater than 1:1. Anomalous trace metals include arsenic, antimony, mercury and thallium. The Melco deposit lies 2.4 km (1.5 miles) southwest of the Barneys Canyon deposit. It is spatially associated with a steeply northwest-dipping siliciclastic breccia in the Kirkman-Diamond Creek Formation at the contact with underlying orthoquartzites of the Freeman Peak Formation. Both gold-bearing oxidized and sulfide lithologies are present, often in sharp contact. Mineable oxide reserves are 2.8 million tonnes (3.1 million short tons) grading 2.40 g/tonne (0.07 oz/ton) gold. Anomolous trace metals include arsenic, antimony, mercury and thallium, which are generally present in concentrations greater than those at Barneys Canyon, particularly in sulfide-bearing material. A spatial, temporal and genetic relationship is proposed between the Melco deposit and late-stage gold mineralization at Bingham Canyon, although both the Melco and Barneys Canyon deposits have many similarities to Carlin-type gold deposits.

Jan 1, 1990

By S. Zendejas-Mendivil, E. Pérez-Segura

The Cananea porphyry copper-deposit is the site of the second largest mining operation in Mexico. Mineralization is related to quartz-monzonite Laramide stocks that intrude volcanic and volcaniclastic Mesozoic rocks. The ore deposit is a stockwork and breccia-pipes system with Cu-Mo sulfides and pervasive quartz-sericite hydrothermal alteration. A study was made of the arsenic distribution in the mine and the ore-dressing plants. The arsenic (As) in the mine is related to a feldspathic quartz-porphyry type rock associated mainly with the breccia pipe structures (100-700 ppm As in the Veta 7 Breccia). There is vertical zoning, with As decreasing in the deepest part of the breccias. This As mineralization corresponds to a later sulfide hydrothermal stage. The concentrates are made of Cu, Fe and Mo sulfides and some minor quantities of As minerals. The most important copper minerals are chalcocite-covellite, bornite and chalcopyrite. Some of these minerals have 390-880 ppm As. The main As mineral is enargite[ [Cu2.97Fe0.06(As0.90 Sb0.01Pb0 01 )0.92 S4 051 and there are traces of stibioluzonite-luzonite I Cu, .95(Aso.4vSbu.49)0.9rfS4.07-Cu2 93(Aso.H4Sba.10)0.94S4.13] and of another stibioluzonite mineral type with substitution of As by Bi[Cu,96(Ascr,,'Sb0ccrB'OJ3jI~6S] These minerals contribute 80% of the As in the concentrates.

Jan 1, 1992

By Robert J. Ramsey, N. Finkelstein, Foster J. Witthauer

First mining operations in the Tyrone District, located just north of the Burro Mountains in Grant County, New Mexico, commenced in the 1870's. A major operation was undertaken by Phelps Dodge Corporation in the early 1900's when a 2,000 ton per day underground mine was developed and a gravity concentrator was built east of the mine and across the Continental Divide. It was during this time that the picturesque Tyrone townsite was built and occupied. In 1921, however, the underground operation was closed because of high operating costs and low demand for copper. The area was drilled extensively during the 1950's and in October 1966 Phelps Dodge announced the pending development of the new Tyrone with a large open-pit mine, a modern concentrator, suitable support facilities, and a new townsite to be located between the mine and Silver City. Stripping for the pit and construction of shop and milling facilities began in 1967. By the spring of 1969, ore was being stockpiled near the primary crusher. Operation of the concentrator on a 3-shift per day basis commenced on July 17, 1969. The concentrator as initially built had one primary, two secondary, and five tertiary cone crushers, two grinding sections of six ball mills each, two flotation sections, four filters, and four tailing thickeners. 'he capacity was about 30,000 tons per day. In 1971 and 1972, the capacity was increased to 48,000 tons per day by the addition of one secondary and two tertiary crushers, one section of eight ball mills, one flotation section, two filters, and four more tailing thickeners. Centralized automatic control was built into the original and expanded facilities to the greatest extent possible, considering the state of the art at that time. Installation of additional control

Jan 1, 1976

By S. J. Swan

A computerized on-line process control system designed to monitor and control the seven-cone copper precipitation operations at Kennecott Copper Corporation's Chino Mines Division in New Mexico has been continuously operating since April, 1972. The cone monitoring system consists of plant sampling components, process measurement instrumentation, on-stream X-ray spectrometer, control computer, typewriters for programming and for operating reports, foreman's communication console, and cone automation hardware. The system provides the following functions: (1) assays for copper and iron from ten process streams on a continuous rotating basis, (2) directs hardware to automatically flush and start up cone units based on measured performance variables, (3) provides continuous plant operating data and calculates metallurgical averages as well as production figures for shift and daily summaries, and (4) provides data logging capabilities. The system is very reliable and improves plant performance by increasing yields, reducing scrap iron consumption, and reducing operating manpower requirements.

Jan 1, 1975

By J. Morris, R. Sellaro

El petrodiesel es un colector común para la flotación de carbón, pero la partición de compuestos orgánicos de diesel (DRO por sus siglas en inglés) en corrientes de proceso no ha sido ampliamente estudiada. Investigaciones preliminares sugieren que bajo esquemas de dosificación normales los contenidos residuales totales de DRO en aguas de procesos deben estar limitados a la fracción soluble en agua (WSF por sus siglas en inglés) sub-ppm. Es más, los hidrocarburos aromáticos poli-cíclicos (PAH por sus siglas en inglés) debería segmentarse de manera proporcional con los compuestos orgánicos de diesel (DRO). El propósito de este estudio fue confirmar estos resultados en pruebas de flotación realizadas en laboratorio. Se midieron los contenidos totales de DRO Y PAH en aguas asociadas con los flujos o corrientes de concentrados y relaves. Los resultados muestran que las aguas con concentrados tenían de manera consistente mayores cantidades de DRO que las aguas de relaves. Es más, los contenidos de DRO en ambos flujos generalmente se incrementaban con el aumento de la dosis de diesel. De acuerdo con la investigación preliminar, los DRO parecían estar limitados a la fracción soluble en agua (WSF) y los PAH tendían a segmentarse proporcionalmente con los DRO. Bajo condiciones de operación típicas, los DRO residuales no deberían representar una preocupación medioambiental, pero deben evitarse situaciones que permitan una sobredosis significativa de diesel.

Jan 1, 2014

By William Gleason

With its 2011 acquisition of rival equipment company Bucyrus International, Caterpillar added underground mining and large shovels to its line of products and further solidified its standing as the leading mining equipment manufacturer in the world with solutions for every aspect of mining. When Caterpillar spent $8.8 billion to acquire Bucyrus, the global mining business was flourishing, as mining companies around the world worked to keep up with demands for nearly every commodity. Flash forward to 2013, and the global mining landscape looks very different. Lower demand for raw material from China and India and falling commodity prices have forced most mining companies to pull back on their production. The reductions from the mining industry have hit equipment makers like Caterpillar and Komatsu hard. In October, Caterpillar reported that its quarterly earnings had fallen 44 percent. The changing conditions have also changed the narrative from Caterpillar and other equipment makers to customers from offering solutions to move the most tons per hour, to now offering solutions for the lowest cost per ton. In September, Caterpillar hosted some of its mining customers and the trade press at its Tinaja Hills Demonstration and Learning Center near Tucson, AZ to talk about its range of products, from its MineStar System designed to help increase efficiency through better equipment management and planning, all the way up to the massive Cat 7495 and 7495HF electric rope shovel lines acquired through the Bucyrus takeover

Dec 1, 2013

By N. R. Hasenmueller, V. Rajaram, R. K. Leininger, D. D. Carr

The content of the paper by V. Rajaram does not fulfill the expectations of the title. But Rajaram submitted the article in October 1983, and he could not have foreseen the numerous developments that would occur before his paper was published more than two years later. Nevertheless, Rajaram failed to mention the interest in oil shale development in southern Indiana beginning in late 1979 and continuing through the present as a result of special financial encouragement of three oil shale projects in May and August 1984 by the Indiana Energy Development Board and the Indiana Corp. for Science and Technology. A session at the 1985 Eastern Oil Shale Symposium in Lexington, KY, Nov. 18-20, 1985, gave the current status of oil shale developments in the eastern United States. Speakers at this session reported on the three Indiana projects. First, Gary D. Aho, Cliffs Engineering Inc., spoke on a feasibility study by Cliffs Engineering and Allis Chalmers for a site-specific pilot plant using the Allis Chalmers process. The plant site is in Clark County, IN, on property of the Midwest Energy Resources Co. The project is funded by $240,908 each from the Indiana Energy Development Board/Corp, for Science and Technology (EDB/CST) and the US Department of Energy (DOE) and $120,454 from the corporate sponsors (total $602,270). Completion is scheduled for mid-1986. Next, Edwin M. Piper, Stone and Webster Engineering Corp., discussed the American Syn-Crude/Indiana Oil Shale Project. This effort followed the completion of two smaller projects funded by the Indiana EDB/ CST: "Testing of Indiana Oil Shale in a Petrosix Pilot Plant" (total funding by EDB/CST at $50,000) and "Assessment of the Petrosix Process for an Indiana Shale Oil Plant" (total funding by EDB/CST at $100,000). The status at the time of the report at the Oil Shale Symposium was that a request for an extension of time for securing nonfederal support had been submitted to the US Synfuels Corp. The proposal included building an 11-m (36-ft) diam retort in south-eastern Indiana to process the New Albany Shale and to produce 366 m3 (2300 bbl) of shale oil per day by the PETROSIX process. The Indiana EDB/CST had contracted with Stone and Webster at $401,100 from EDB/CST and $245,835 from Stone and Webster for activities to advance the project in the negotiations with Synfuels Corp. At the time of the report, this project was the only eastern oil shale proposal that was still on the agenda of the Synfuels Corp. As a result of Congressional action in late December 1985, federal support from the Synfuels Corp. is no longer possible. Finally, Victor H. Carr, Eastern Shale Research Corp., described his firm's project, which is jointly supported by DOE ($227,749) and the Indiana EDB/ CST ($73,850) and is entitled "Feasibility Study to Determine Suitability of an In-Situ Process to Recover Hydrocarbons from Eastern Shale." An area in Scott County, IN, had been chosen, but not a specific 9 x 15-m (30 x 50-ft) site. One burn of a small in situ retort is contemplated as part of the project. Besides these three projects, several reports on shale research were presented. Joseph Damukaitis, American Syn-Crude Corp., reported that a pilot plant using the hydrogenation-extraction (H-E) process (described at the 1984 Eastern Oil Shale Symposium) was 94% built and would go through shakedown with oil shale but would then shift mechanical devices to process coal mine waste. Current status of research on the HYTORT process was then presented by Raymond C. Rex, Jr. Oil shale beneficiation research at the University of Alabama/Minerals Research Institute was reported by R. Bruce Tippin. Scott D. Carter discussed continued research on fluidized-bed retorting of shale at the Kentucky Center for Energy Research Laboratory. Carl E. Roosmagi of DOE, Morgantown, reported on the oil shale research at the Morgantown Energy Technology Center (METC) laboratory. Henry J. Gomberg, Ann Arbor Nuclear Inc., discussed "Radiation Combined with Donor Solvents for Extraction and Up-Grading of Kerogen." Aurora M. Rubel and coauthor Eileen Davis presented results of research at the Kentucky Center for Energy Research Laboratory under the title "The Effect of Shale Particle Size on the Products from the Bench Scale Fixed Bed Steam Pyrolysis of Kentucky Sunbury Shale." Lastly, Maria Rockwell, Technical University of Nova Scotia, presented "Processing and Up-Grading of Low Grade Nova Scotia Oil Shale for Potential Use." A review of shale oil prospects by Gerald Parkinson in Chemical Engineering for Feb. 3, 1986, covers both western and eastern projects and includes a report that the US DOE is funding a few relatively small projects; most of the fiscal 1986 budget of $12 million for shale oil is for fundamental research. Projects include a $3.2 million three-year contract with Hycrude Corp. (Chicago) for development of the HYTORT process and a $1.2 million three-year contract with the University of Alabama's Mineral Resources Institute on beneficiation of eastern oil shale by froth flotation. The report incorrectly states that current projects include a total investment of $466 million in a pair of 18-month technical and economic feasibility studies for proposed projects in southern Indiana. The correct figure is $468,657 [$240,908 for the Cliffs Engineering/

Jan 1, 1987

By Yong Yuan, Wenhao Xiao, Luc Taerwe

"The static shear stiffness of an immersion joint subjected to combined compression and shear forces is investigated by experiments in a test set-up. To explore the performance of the immersion joint, the compression-shear loads, which are applied on a specimen according to test protocol, are determined based on real design situation. In this test, the main focus is on the steel shear keys and the rubber sealing. For the applied loading schemes, different levels of axial force, corresponding to the water depth of the joint, are considered as well as the changing amplitudes of the shear force. The force-displacement curve is obtained and the hysteresis is observed during the whole test. The joint‘s static shear stiffness is calculated, showing to increase linearly with respect to the magnitude of the axial force. Moreover, it is found that the rubber sealing has a significant influence on the shear behavior of the joint. INTRODUCTION An immersion joint is the connecting part between two adjacent elements of an immersed tunnel. Compared to that of the bulk elements, the stiffness of the immersion joint is relatively small. When it is subjected to shear actions, whether resulting from vertical foundation settlement or horizontal earthquake movements, shear-resistance of the joint is the main concern for a safe and reliable water-proof design. A flexible immersion joint, which normally consists of a rubber seal and shear keys installed at an element end is a common solution in practice. The way in which the shear keys and the rubber seal behave in the joint together is of vital importance to a comprehensive understanding of the shear behavior of the joint. However, in literature very few experiments on the shear behavior of immersed joints are available although the flexible joints are applied in practice for more than 50 years already. O. Kiyomiya (2004) carried out both a 3-dimensional experiment and a finite element analysis for a new type of flexible joint referred to as the Crown Seal. The results indicated that this new type of joint can be applied in practice because of the effective reduction of lateral deformation. A linear model was found in the paper of Anastasopoulos et al. (2007) to describe the behavior of the shear keys, which consider that the stiffness of the shear keys tends to infinity. R.S. van Oorsouw (2008) discussed the shear capacity of concrete shear keys in segmental joints, by analyzing the influences of reinforcement and friction force between shear keys."

Jan 1, 2016

By S. Perla

Two of Peabody Western Coal Company's mine operations are the focus of this paper ... Black Mesa Mine and Kayenta Mine, both located in Northern Arizona. These two locations are unique for a variety of reasons. ? The two mines have only two customers, both power plants, one the Southern California Edison's Mohave Generating Station near Laughlin, NY, the other the Navajo Generating Station near Page, AZ. Close in proximity, these two locations ships nearly 12 million tons of coal per year. ? Material is shipped to these customers two ways: via a 273 mile underground slurry pipeline, which by the way is longest in the world, and by a 17 mile long conveyor to four storage silos. Product is then shipped via train from the storage silos to the plant sites.

Jan 1, 1995

By Ying Lu, Jeffrey C. Johnson, Chen-Luh Lin, Jan D. Miller, Sindhoora Puvvada

Energy dissipation and fragmentation of rock is of interest for mine-to-mill operations in order to understand breakage and to minimize energy consumption during blasting at the mine site, and comminution at the processing plant. In this regard, high velocity impact breakage of long granite cores, called bars, has been studied with instrumented strain gages to follow the energy dissipation gradient along the bar length resulting from the strain waves generated by impact. As a result of high velocity impact, three zones have been identified (fragmentation, fracture, and elastic) and these three zones have been characterized in 3D using X-ray tomography. The fragmentation zones of the granite bars were studied in detail to describe the particle size distribution and the particle shape characteristics. Finally, the experimental energy dissipation for the fragmentation zone was found to be in close agreement with the expected energy calculated from the Bond work equation, if the anisotropic granite particles are defined by length rather than by sieve size.

By Peter A. Dawson, Rod L. Leonard, Karen S. Christensen

An investigation has been completed of the technical and economic feasibility of construction of a processing facility for gold extraction from arsenical tailings, grading nearly 12 g/t, stockpiled near Snow Lake, Manitoba, Canada. The tailings dump is comprised of arsenopyrite (45%), pyrrhotite (12%), and gangue constituents. The majority of the gold occurs as fully encapsulated particles or as a solid solution in the arsenopyrite grains. The chemical composition of the Snow Lake tailings (referred to as "ore" throughout the remainder of the text) is shown in Table 1.

Jan 1, 1990

By John B. Rigg

Thank you Mr. Chairman. It was a generous introduction. It allays some of the puzzlement I have of being a minority among the speakers at this conference. I see from the program that only two of us have been asked to speak on topics in keeping with an election year. Instead of reporting facts on past events as most speakers are, J. W. Wilson, of Consolidation Coal, and I have been designated to forecast the future. Forecasting in an election year implies a liberty to fabricate at will, hallucinate, fantasize, stretch fact and fancy and generally prognosticate without regard for the consequences. Since I'm not seeking your votes, promises aren't mandatory. This will be done with supreme confidence stemming from profound wisdom and a foolproof crystal ball. So instead of soliciting your vote, I'll simply penetrate 24 years of tomorrows, which may not be much different than some of us remembering the later hours of last night. My remarks do not draw upon Gulf planning department projections. Instead they are a roll of the dice of personal conjecture to stretch your imaginations on oil shale mining through the year 2000. In this regard, it is sobering to keep in mind that it has been in my lifetime that investors wouldn't risk a dollar on paperback books, motels, supermarkets, or drive-in restaurants. And only thirty years ago it was predicted by an eminent Ivy League professor

Jan 1, 1976