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By Layton C. Binon

Exploration budgets are commonly determined by "rules of thumb" such as a percentage of earnings or other fiscal measure. An appropriate exploration budget is the amount needed to achieve the goals of the company. It can be determined by discounting the income expected from achieved goals. Budgets for individual projects are determined in a similar manner except that risk of failure is included in the computation.

Jan 1, 1981

By John J. Peregoy, James E. Downes

INTRODUCTION The U.S. Department of Energy's Waste Isolation Pilot Plant (WIPP) is being constructed to provide permanent storage of radioactive TRU waste materials emanating from military weapons production. These wastes are contaminated with radioactive elements heavier than uranium, thus the name trans-(or beyond) uranic (Uranium wastes). The WIPP site, which is located 26 miles east of Carlsbad, New Mexico, was chosen thru a selection process after the National Academy of Sciences recommended salt deposits as a promising host strata for the storage of radioactive wastes. Throughout the United States numerous DOE facilities have produced and stored defense-generated TRU wastes. Once WIPP becomes operational in the fall of 1989, all sites may ship directly to this repository. A companion project has developed special shipping containers (TRUPACT) for safe transport of materials to WIPP. The WIPP facility is currently composed of surface buildings, three shafts, and underground storage and experimental rooms and tunnels. Frontier-Kemper Constructors, Inc. (FKCI) has nearly completed the construction of the fourth shaft, an intake shaft, to provide additional ventilation to the underground workings. PLANNED SHAFT EXCAVATION METHOD Full-face raise boring ( upreaming ) was the allowable method selected by Frontier-Kemper Constructors for the excavation of the shaft. After arrival of an oil-field type rotary drill rig in December 1987, a 9 inch diameter pilot hole was drilled from the surface to the mine level, a depth of approximately 2145 feet.

Jan 1, 1989

By Haydn H. Murray

Although alumina constitutes about ii percent of the earth's crust, it is expensive to separate and purify for the production of aluminum with the exception off the alumina in bauxite. The United states has a variety of non-bauxite resources that could substitute for bauxite, including high alumina clays, alunite, dawsonite in oil shale, anorthosite, and nepheline syenite. Each of these resources are discussed from the standpoint of geology, geography, processing, potential recovery, and environmental problems. Potential by-products include silica from clays, potash and sulfuric acid from alunite, soda ash from dawsonite, and soda ash and potash from anorthosite and nepheline syenite.

Jan 1, 1982

By T. A. Toney

A sampling program was conducted in 2008 to determine the run of mine characteristics of 5 coal seams. The sampling program included size analyses and float sink determinations. The samples were analyzed for ash and mercury concentrations for each size and gravity fraction. This paper will report on the sampling program, the analytical results, and the correlations determined in the data set investigated.

Jan 1, 2010

By Michael R. Grubbs

In most resource recovery plants the incoming solid waste material is first shredded and then air classified into a light and a heavy fraction. The light fraction which contains mostly paper, cardboard, etc., can be used either as a fuel for power generation or in the production of new paper products. The heavy fraction which remains consists mostly of glass, ceramics, wood, ferrous metals and non-ferrous metals. The ferrous metals may be removed from the heavy fraction by conventional magnetic separators. After primary shredding, most of the glass and ceramic is fine in size and may be screened away leaving a residue of wood, cardboard, and non-ferrous metals. This residual heavy fraction is the input material for the separator described in the present paper. A new metal separator was recently reported by t. Schlömann1. The author described the theoretical relationships and presented results of tests on samples of the residual fraction of municipal solid waste. This paper describes the operation of the metal separator and develops the basic separation relationships controlling the process.

Jan 1, 1976

By Haydn H. Murray

Since the advent of machine coated paper in the mid 1930's, the kaolin industry has had a remarkable growth, In 1935 the domestic production of kaolin was 500, 000 tons and in 1970 the estimated production was in excess of 3. 5 million tons. The process industries which use kaolin most extensively are paper, rubber, paint, ceramics, plastics, catalyst manufacturers, ink, and pharmaceutical. The paper industry is by far the largest consumer of kaolin using approximately 70 per cent of the total tonnage mined and beneficiated. Up until 1970 the major kaolin producers were able to expand rapidly enough to supply the demand but for the first time in thirty years the demand is expected to be in excess of mining and beneficiation capacity through at least 1975. The major reason for this is the expansion of coated paper production in Europe and Japan. Two areas supply the lion's share of kaolin for the world markets. These are the Cornwall area in extreme southwestern England and a limited area of Georgia and South Carolina in the southeastern U. S. The English kaolins are primary - (found in decomposed granite) whereas the Georgia-South Carolina kaolins are secondary - (found in lenticular, continuous beds in the Tuscaloosa formation of Cretaceous age. ) The English kaolins are mined by hydraulic methods whereas the Georgia-South Carolina kaolins are mined by dragline or shovel and benefidated by using a wet process for the majority of the production and/or a dry

Jan 1, 1971

By D. A. Stanley

Researchers at BCD Technologies and the University of Alabama have applied three statistical techniques to the information contained in a large database of measurements from a phosphate ore processing plant. The rust, Principal Components Analysis (PCA), replaces many measured variables with a few fundamental and un-correlated variables. The second technique, Projection to Latent Structures (PLS), is an extension of PCA that explores the relation between variables identified as either independent or dependent. The third technique, Cluster Analysis (CA), is applied to the results of the PCA or the PLS calculations, and identifies individual data clusters that represent uniform operating conditions in the plant. All three statistical methods can be seen as geometrical operations on the data viewed as points in space. A Viewer gives a corresponding graphical presentation of the data points. This paper describes the use of the above three techniques and the Viewer to explore part of the phosphate flotation database.

Jan 1, 1998

By Robert J. Garino

Around two-thirds of world silver mine production comes from mines where the majority of ex-mill revenue is obtained from other metals. In this talk I will illustrate the importance of this output of silver as a by-product of the mining of various base metals. I will also consider the impact of relative changes in base and precious metal prices on mill-head revenue, and therefore, on production decisions. During the latter half of 1982 improving silver prices encouraged re-openings at several base metal mines. Thus some production of lead, zinc and copper can be regarded as partly conditional on the prevailing silver price. Conversely, a good deal of silver production can be considered to be independent of the silver price and dependent on the production of some base metal. It is the degree to which the value of silver mined affects the revenues of nominally, base metal, producers that is the central concern of this presentation.

Jan 1, 1983

By T. Shumka, M. J. Druckenmiller

"INTRODUCTION As we push further into the 21st century and closer to a more efficient mine, safety and operational enhancements are the two major keys towards attaining success. The Crusher Vision Automation System (CVAS) is a technological advance that will allow an operator to achieve higher safety and higher operational goals in the same piece of equipment. The CVAS is a patent pending system and method for measuring and maintaining the closed side setting (CSS) on gyratory crushers. In the same equipment and technology package, the CVAS will also allow safer placement of main shaft pieces for maintenance and replacement. This technology yields multiple uses and allows a site to significantly enhance safety and operational efficiencies. This measurement technique is used to provide more accurate data and faster data collection times than current techniques used today. It will give crusher operators accurate and reliable measurement for the CSS in a live, operating environment. Measurement data can be collected in five minutes allowing for fast adjustment of the mantle position and subsequent enhancement and streamlining of a crusher and downstream flowsheet. The advantage of this system is that it is permanently mounted at the crusher location, where the operator can turn the system on and off as many times as they like throughout the day with a goal of maintaining a constant CSS gap based on production and maintenance criteria to help streamline operations and enhance safety efficiencies.Regarding its other main functional area, mainshaft maintenance, it allows this work to be performed remotely while keeping personnel safer and out of harm’s way. SAFETY ENHANCEMENT The safety factor enhancement with this system is extreme. It does not require the use of overhead cranes, cleaning out the crusher, lowering people into the crusher or having the operator lower paint cans or lead balls into the crusher pocket while the crusher is in operation for measuring the setting. In order to perform the CSS measurements, the operator only needs to operate the laser through manipulation of a joystick while watching the video feed. Danger of a person falling into the crusher while trying to take measures is eliminated, as are the effects of handling lead balls and tracer dyes."

Jan 1, 2015

By J. J. Kellar

The near-infrared (NIR) (12,000-4,000 cm-1) region of the electromagnetic spectrum, between the mid-infrared and visible, has often been viewed by spectroscopists to be of limited utility. This is unfortunate, and recently the use of the NIR has increased greatly, primarily for the quantitative analysis of food and agricultural products. However, many other areas of application of NIR spectroscopy remain unexamined. In this paper a novel use of NIR in the area of flotation chemistry is demonstrated. Specifically, it is shown that NIR/Internal Reflection Spectroscopy (IRS) can be used to quantify collector adsorption reactions in-situ.

Jan 1, 1990

By Walter Meintrup

On Nov. 4, 1981 the newly installed 1000tph wet-process iron-ore ball mill of A/S Sydvaranger completed its first four months of uninterrupted, successful full-load operation in Kirkenes/Norway. This 6.5m diameter mill is driven by a gearless ring or wrap-around motor of 8100kW at 13.1RPM - a first of a kind in this segment of industry. (Fig. 1) This paper analyses the reasons that have led to the selection of this type of drive over more conventional schemes, lists specific advantages of such large mills, and describes in some detail the installation in Norway. General aspects of possible design variations, and application information for designers and users of such mills conclude the presentation.

Jan 1, 1982

By Vernon R. Shorter, Wayne N. Clark

Introduction Coal is the US's largest indigenous fossil fuel resource and is used to power 57% of this country's electrical generation (NCA, 1986). Congress, however, is focusing its attention on the acid rain issue and public sentiment is leaning toward further curtailments of SO2, NO, and particulates from utility and industrial coal-burning facilities. The Cool Water plant has proven that integrated-gasification-combined-cycle (IGCC) technology can reliably produce economical electrical power while limiting SO2, NOx, and particulates to a rate of only one-tenth of the federal New Source Performance Standards for coal-fired plants. Process water requirements at Cool Water are 40% less than those of a conventional coal-fired utility plant equipped with flue-gas desulfurization units for stack gas scrubbing, thus reducing waste water treatment requirements (Clark and Shorter, 1985). The IGCC technology employed at Cool Water has now been demonstrated to efficiently convert coal to electricity in an environmentally superior fashion. The Cool Water Coal Gasification Program is an unincorporated California association of six partners whose commitment is proving that the integration of gasification with combined cycle power production (IGCC) is commercially viable and environmentally safe. The 120 MW Cool Water plant began commercial production on June 24, 1984. The Program is operating it for a five-year commercial demonstration period. The Program is about halfway through this period. Much of that which was intended to be proven is now fact. In this mid-term assessment, the authors report that the com-

Jan 2, 1987

By Eddy J. Jacques

When the automatic control of a ventilation process is considered, and supervising expert systems need to be designed, an important problem to address is: what will be the optimal set points of the regulators that should meet a certain number of independently formulated requirements, distributed over a ventilation network? The set of these requirements, expressed in terms of air flow quantities or differential pressures in certain airways, need not be consistent. Their number is not limited by the number of available regulators, nor by their nature, i.e. passive or active. Moreover, they may be subject to upper or lower limit values. The method described here addresses this problem and tries to provide a tool that should allow to calculate the set points of all the regulators as a global and optimal solution with respect to this set of distributed requirements. The pure mathematical developments in this paper are kept as short as possible in order to allow more room for the description of a relevant example.

Jan 1, 1991

By J. C. Yingling, J. W. Leonard

Introduction The absence of coal-face particle management heavily penalizes the transportation of coal from initial loading to final consumption. The penalties include dust problems, significantly reduced mine-loading-cycle productivity, mine-belt spillage, excessively high coal-preparation costs, chute blockages and dangerous pulverizer blockages at the final point of utilization. Fine particles commonly cause environmental and economic problems. It is well known that these fines can cause safety and environmental dust problems. But it is not well understood that these fines can also swell broken coal to a point where 5% to 15% more time and capacity must be used to deliver the same tonnage. In this paper, methods and rewards for reducing and/or managing fines at the mine face are discussed. Computer-based loading-cycle model productivity estimates, viewed from a new perspective, are made on the basis of material volume rather than on the long-established, and frequently misleading, basis of tonnage. It is typically the volume of broken material being transported that defines the capacity of a given transportation system, while the corresponding tonnages are merely a reflection of the specific material densities. Published evidence suggests that the swelling of broken coal can be decreased very significantly using small quantities of certain nonfrothing chemicals, which are added to mine-face spray water, and by employing improved mine-face breakage practices. In a future paper, the effects on transportation productivity beyond the coal mine will be discussed. The precursor to the work presented in this paper, involving the bulk density improvement for broken coal and the subsequent production gains for underground coal mines, was earlier presented in Leonard and Newman (1989). In the past, this topic has been studied and practiced only in byproduct coking in the steel industry. However, a potential exists for an increase in coal-industry productivity by improving the bulk density of coal to yield a subsequent reduction in delivered cost. This can occur with breakage, handling and treatment methods resulting in the loading of greater quantities of coal in fixed volumetric capacity haulage units such as mine cars, shuttle cars and scoops. Laboratory-based experiments to achieve an increase in productivity by increasing coal bulk density were discussed in Leonard, Paradkar and Groppo (1992). Chemical techniques using small quantities of commercially available reagents (surfactants) resulted in about a 13% to 15 % increase in bulk density, which was thought to produce a proportional increase in the productivity of a mine, together with a subsequent reduction in cost. The idea is to mix the reagents with the water that is used to spray coal during mining. In this paper, the impact of bulk density improvements on production rates is presented. Increases in production ranging from 60% to 88% of the bulk density increases are projected. This analysis was performed for atypical continuous-miner section. In the following sections, discussion and results of the analysis are presented. Discussion An analysis was performed to ascertain the impact of bulk density improvements on face-production rates for a typical continuous-miner section. Figure 1 illustrates the section layout and cut sequence. This layout and sequence is identical to the case described in King and Suboleski (1991). As can be seen, the section uses five entries and 12.2-m cuts that are taken by a remotely controlled continuous miner. The seam height is 1.5 m and two shuttle cars (5.7 t nominal capacity) are employed for haulage from the miner to the section feeder, which, throughout the cut sequence, is positioned as illustrated in Fig. 1. The simulation model was coded in the SIMAN simulation language. The major impacts of increased bulk density improvements on such a production system are as follows: •Shuttle-car payloads, in terms of the mass of coal transported per haul cycle, are increased proportionally to the increase in bulk density that results from the application of surfactant. •Shuttle-car discharge times should remain largely unchanged, because they are determined by the volume of material that is discharged, rather than the mass, and this volume does not change.

Jan 1, 1996

By Stanley J. LeFond

The Republic of Botswana, one of the newer countries of southern Africa, attained independence on September 30, 1966. It covers an area of about 225,000 square miles (582,000 square kilometers) which makes it slightly larger than France, or slightly smaller than Texas. It is bounded by Zimbabwe, the Republic of South Africa and Namibia, including the Caprivi Strip. Angola and Zambia are close neighbors. (Map 1). Botswana lies at the center of the southern African plateau at a mean elevation of 3,300 feet (1,000 m). It is a natural habitat for most species of African fauna. The rolling sands and extensive grasslands of the Kalahari Desert cover the southwest. The climate is sub- tropical. Summers, although tempered by north- easterly breezes, are hot, but mean maximum temperature seldom rises above 100°F (38°C). Winters are dry with wide temperature variations, which often give rise to frosts.

Jan 1, 1981

By J. D. Vincent

The Henderson mine site is located at Red Mountain on the eastern slope of the Rocky Mountains, approximately 50 miles west of Denver, Colorado. The mill site is on the west slope of the Rockies and mine and mill will be connected by an underground railroad. All designs were for a 30,000 ton per day molybdenite processing plant with provisions for future expansion up to 50,000 ton per day if required. This plan did not just happen, but slowly evolved over the course of about three and one-half years. Many plants cannot afford such a delay, but the Henderson project will take about 10 years from the time it was first discovered until production starts, and these 3 !1 years were well spent in determining the best possible plant site and flowsheet. This paper describes some of the problems and the decisions made in arriving at the final location and flowsheet. The paper does not go into the specific details of how protection of the environment went hand-in-hand with all other project considerations. This particular aspect of the planning has been well-reported on other occasions and considerable information on it is readily available.

Jan 1, 1972

By Edward C. Krug

"You are to use the word ... purely for its selling power. It is a name they venerate. As a result, you can use the word ... to ... get [them] to practice, not only without shame bit with a positive glow of self-approval, conduct which, if undefended by the magic word, would be universally derided." (C.S. Lewis, The Screwtape Letters, 1982, p. 162). "We need to tear everything down over a period of time and reconstruct a whole new world, planned top to bottom. "Right now there are just way too many people on the planet [5.3 billion]. `If we had ... an ethic ... we could cut back to 250 million-350 million people. `The United States is ... a bunch of pigs ... the average citizen ... [uses] maybe 70 to 80 times as much as anyone in the Third World.` "The indigenous pople were the ones that were right! I mean, they had their own religion, their own ethics and their own technology. We just went down a wrong road. "So when he says, `We got to rebuild the whole world,' you have no doubt this is serious sentiment .... And it is finally this world view that distinguishes (Ted) Turner as a media mogul and an environmentalist. It is why Worldwatch's Lester R. Brown told me Turner was `truly a visionary. "'(Interview of Ted Turner, Audubon magazine, November-December 1991. On Dec. 28, 1991, Ted Turner was name Time magazine's "Man of the Year." Clearly, media and environmental leadership agree with Turner's openly stated beliefs.)

Jan 1, 1992

By Joseph Lynch, John DiPonio

This report refers to the Chicago Deep Tunnel Contract 13A, which was the first contract let in the City of Chicago requiring the construction of deep drop shafts for the transportation of high level sewage to the deep tunnel system. The basic contract required the contractor to construct certain drop shafts designed to deliver surface and high level sewage to the deep tunnel system approximately two hundred feet below. The design of the drop shafts was in a degree affected by their proximity to the existing deep tunnel. The tunnel, approximately three and one-half miles long, was to have five shafts dropping sewage at five locations. Four of the drops were approximately one-half mile apart and spaced from the dead end of the tunnel. One shaft divided the remaining two miles from the existing work shaft at the southeast end of the tunnel wherein a 220' deep pumping station was to be built. The existing tunnel had been built some time previously and all dewatering had stopped, allowing the tunnel and main shaft to fill with water. According to the plans, the drop shafts were all between fifty and ninety feet north or south of tunnel center line, and located in heavily built-up residential and industrial property. This then defines the problems: How do we control the water. If we excavate from the top down, how do we handle the slurry and the muck from five locations. How shall we construct the connecting tunnel between

Jan 1, 1997

By T. P. Lim, A. J. Vivyurka, N. K. Davé

Chemical and radioisotope stratification studies were carried out in an abandoned uranium tailings pile at Elliot Lake, Ontario, Canada. The tailings, with an average thickness of 7 m over an area of 16 hectares, were deposited approximately 20 years ago on a layer of black peaty material which overlays deposits of permeable glaciofluvial sands. Geohydro-chemical investigations of this tailings area have been ongoing since 1978. The radioisotope profile study was conducted on three adjacent sites. Solid core samples, collected with a split spoon sampler at various depths, were analyzed for various chemical and radioisotope constituents. The results indicated by 2 distinct zones of stratification; an upper zone, where the constituents were uniformly distributed, and a lower zone, near the peat-tailing interface, which showed increasing concentration with depth. Within the peat layer, the concentration decreased rapidly with no significant levels of contaminant penetration below the peat layers observed, though the samples were limited. The pH profile showed that the top 5 m of the tailings have been oxidized, the average soil pH in this zone was 3.4 compared to 5 .8 underneath it. The groundwater hydrology of the system was observed to be complex showing downward and lateral flow in the dry season and lateral and upward flow during the spring and periods of heavy rainfall. The results are discussed in terms of a model based on the combined segregation and settling process of the tailings fine fraction, and the geohydro-chemical interaction of the solid and liquid phases.

Jan 1, 1981

By William A. Rehrig

During recent years, there have been frequent investigations on the geochemistry of biotite. This work has emphasized, and no doubt was prompted by, factors related to mineral exploration, particularly for those deposits of the porphyry copper type. A large number of papers have been devoted to the obtainment of trace-element data from plutonic biotite. These data have been used to extract primary geochemical information pertaining to the parent magna and the hydro-thermal system which together give rise to porphyry copper deposits. In two early works, Putman and Burnham (1963) and Parry and Nackowski (1963) analyzed base metal contents of ferromagnesium minerals, primarily biotite, from various barrenfmineralized plutons of the Basin and Range Province. One similar conclusion from the two studies was that the Cu, Zn, and Pb contents of magmatic biotite served as indicators of ore development within the granitic rocks genetically related to ore. This theme was then pursued vigorously by a number of authors until the present time. Results, however, have been contradictory, as reviewed by Coope (1974). For example, studies by A1 Hashimi and Brownlow (1970), Lovering et a1 (1970), Putman (1972), and Graybeal (1973) continued to support positive primary relationships between the trace-metal content (usually copper) of biotite and associated sulfide mineralization. By studying biotite in close spatial association will sulfide occurrences, Putman (1972) and Graybeal (1973) developed models for base metal partitioning in magmatic systems based on their discovery of inversely distributed copper between silicate (biotite) and sulfide phases. Conversely, research by Bradshaw (1967) and Blaxland (1971) plus the recent findings of Parry and Jacobs (1975) and Kesler et a1 (1975) found little if any evidence to support a correlation of biotite base-metal or

Jan 1, 1976