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By L. H. Bergmann

THE blasting practices described are fairly representative of those employed in the coal mines of Eastern Canada. As such, they may be of interest to Western Canadian coal mine operators. The treatment of the subject is general, no attempt being made to discuss blasting operations at any particular coal mine in detail. All the mines dealt with are mining bituminous coal and are classified under the Coal Mines Regulation Act of the Province of Nova Scotia as 'closed light' mines. As such, they are required to use only 'permitted' explosives and to apply them in a 'permitted' manner, except where authority is given by the Mines Department to do otherwise.

Jan 1, 1945

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 Verne Huser

The intensity of environmental conflict, the delays and legal battles that have marked the 1970's suggest the need for additional processes to resolve environmental disputes. Our present means frequently fail to address the real issues separating individuals and institutions. They are primarily adversary processes that foster polarization and reduce cooperative efforts. At the Office of Environmental Mediation, we have no quarrel with adversary processes nor with polarization, for both serve as important spurs to necessary change. We do seek cooperation among parties at a point where there can be a realistic expectation of success in facilitating a resolution of their mutual differences.

Jan 1, 1979

By J Meinhart, J Rodler, I Katolicky

The ever increasing number of vehicles is leading to slow-moving and even stationary traffic sitting longer in traffic jams over extensive city areas. This traffic situation causes a sharp increase in pollutant emissions from vehicles, and high levels of pollution usually result throughout the built-up area. Reducing the pollution level by using traffic routing measures to speed up the flow of traffic in the existing street network is only possible in exceptional cases.In many cases the only option for achieving a significant improvement in traffic conditions is to shift the traffic underground using a road tunnel or underpass. Such tunnel routes suck off the traffic from large sections of the city, thereby easing the overall traffic flow. Thus on the one hand it produces a sharp reduction in pollution levels in the area of the tunnel route, but on the other hand it can result in locally increased exhaust pollution levels from longer tunnel systems that require mechanical ventilation. The air extracted by the ventilation system is blown out into the atmosphere either directly through the tunnel portal, or via a venting tower. Pollution can therefore occur in the area surrounding such exhaust air outlets.Thus if a tunnel is planned in a city, then closer investigation is required of both aspects: the reduction in pollution in the area of the tunnel route thanks to relocating the traffic and easing congestion, and the increased short-range pollution around the tunnel portals (shafts).

Jan 1, 1999

By G. A. Koenig, Moritz Stockder

Locality and Geological Occurrence. The Alpine region of Southwest Colorado, comprising the San Juan and Uncompaghre Mountains, is composed of a deeply eroded sheet of acid eruptive rocks, overlying in part gneissic sehists, and in part limestones and sandstones, including portions of the Silurian, Devonian, and Carboniferous systems. The section is clearly and beautifully exposed along the Uncompaghre River from its headwaters to its exit from the mountains. The river's course from the town of Ouray towards the Los Pinos agency is due north, and four miles from Ouray, in this direction, the Uncompaghre receives from the east the Red Cafion Creek. Following up the narrow caftan we find the section through white.. sandstone in strata dipping to the north and west, and belonging either to the lower or middle Devonian system. Presently the steep cafion-liko character of the ravine gives place to more gentle slopes, and we have entered crystalline rock-porphyry. The contact is well marked, for the sandstone, to a depth of from six to ten feet, resembles quartzite, i. e., is semifused. Ascending still higher, a small

Jan 1, 1881

By J. L. Lehman, J. D. Sudbury, J. E. Landers, W. D. Greathouse

A full scale field experiment on cathodic protection of casing answers questions concerning (1) the proper criteria for determining current requirments, (2) the amount of protection provided by different currents, and (3) the transfer of current at the base of the surface pipe. Three dry holes in the Trico pool in Rooks County, Kans., were selected for cathodic protection tests. The three holes were in an area where casing failures opposite the Dakota water sand often accur in less than a year. Examination of the electric togs showed the wells to be similar to other wells in the field where casing in four of seven producing wells has failed. The three holes were cleaned out and cased with 75 joints of new 51/2-in. 14-tb J-55. Each joint was visually inspected and marked before it as run. The casing was bull plugged and floated in the hole 50 that the inside might remain dry and free of excessive attack. Also, if a leak occurred, a pressure increase could be observed on gawge at the surface. Extensive testing was done, including potential profiles, log current-potentid curves and electrode measurements from both surface and downhole connections. Based on these data, a current of 12 amps was applied to one well and 4 amps to mother. The third well was left to corrode. During the two-year period when the casing was in the ground, [he applied current was checked weekly, and reference electrode measurements were made about every two months. Three sets of casing potential profi1e.c were run. When the three strings were pulled, each joint was examined for type of scale formed, presence of sulfate-reducing bacteria, extent of corrosion nttnck and pit depth. Since the pipe was new when run, quantitative determination of the protection provided by current was possible. This is the first concrete field evidence to help resolve the many arguments about the proper method for selecting adequate current for cathodic protection of oilwell (-using. INTRODUCTION A casing string is run when a well is drilled. This pipe is supposed to protect this valuable "hole in the ground" for the life of the well. Often the casing does not last the life of the well; it is with these casing failures that this work is concerned. The cost of repairing a casing failure varies from field to field—from as much as a $30,000 per leak average in California to $5,000 per leak in Kansas. Additional costs other than actual repairs are also important. These include formation damage, lost production, etc. Casing damage caused by internal corrosion is important in some areas. Treatment normally consists of flushing inhibitor down the annulus, but further research is being done on control measures. The test described in this paper is concerned only with external corrosion. The problem of casing failure from external attack has appeared in several areas including western Kansas, California, Montana, Wyoming, Texas, Arkansas and Mississippi. Cathodic protection is currently being used in an attempt to control external corrosion. From reports in the NACE there are thousands of wells currently under cathodic protection. The quantity of current being applied ranges from 27 amps on some deep California wells to a few tenths of an amp being supplied from magnesium anodes on wells in Texas and Kansas. Considerable field and laboratory effort1,9,5,6 was exented on the problem of cathodic prctection of casing, and it became fairly obvious that this method could be used to protect wells. Early workers showed that current applied to a well distributed itself over the length of the casing and was not concentrated on the upper few hundred feet. Basic cathodic protection theory had shown that corrosion attack could be stopped by applying sufficient current. The problem resolved itself, then, into one of trying to decide just how much current was necessary. Various criteria were utilized in installing the many existing cathodic protection installations. These methods included the following. 1. Applying sufficient current to remove the anodic slope as shown by the potential profile." 7. Applying enough current to maintain all areas of the casing at a pipe-to-soil potential of .85 v.' 3. Applying the current indicated by a log current-potential (or E log I) curve." 4. Supplying the current necessary to shift the pipe to-soil potential .3 v." 5. Applying 2 or 3 milliamps of current per sq ft of casing."

By A. Juganda, Jr. Bogin, S. Saki, R. Gilmore, J. Brune, J. Grubb, S. Lolon

"In longwall mines, atmospheric or barometric pressure fluctuations can disturb the pressure balance between the gob and the ventilated working area of the mine, resulting in a phenomenon known as “gob breathing”. Gob breathing triggers a gas flow across the gob and the working areas and may result in a condition where a methane accumulation in the gob flows into the face area forming an explosive mixtures. This paper discusses results of Computational Fluid Dynamics (CFD) modeling carried out to analyze this phenomenon and its impact on the explosive mixture development under a bleeder-ventilated longwall gob panel scheme. Modeling results indicate that the gas inflow and outflow across the gob and the formation of Explosive Gas Zones (EGZs) are directly affected by the barometric pressure changes. Methane gas and EGZs in the gob expand out toward the face and bleeder entries during the falling barometric pressure. Where methane zones interface with mine air, EGZ fringes may form along the face and in the bleeder entries. When the atmospheric pressure increases, an ingression of oxygen into the gob is observed that can also increase EGZs in volume. The findings from this study help assess the methane ignition and explosion risks associated with fluctuating atmospheric pressures. INTRODUCTION Methane explosions continue to be a daunting risk for underground coal miners, although the number of related fatalities and injuries in the U.S. coal mining industry has steadily decreased since the establishment of the U.S. Bureau of Mines in 1910. Still, the consequences of a methane explosion are often disastrous with multiple fatalities and property damage often leading to permanent shutdown of the mine. Methane is formed during the coalification process and is released from the coal seam to the mine atmosphere when the coalbed is disturbed by mining or natural causes such as earthquakes. If not properly diluted by appropriate mine ventilation, this methane may accumulate in the active mine workings and gob areas. Researchers at the Colorado School of Mines have developed numerical models showing how and where explosive methane may accumulate in gob areas. Historical mine explosions appear to show a connection between mine explosions and fluctuating barometric pressure as a result of stormy weather. McIntosh (1957), Boyer (1964), and Kissell et al. (1973) studied the influence of barometric drops on major coal mine disasters in the United States prior to 1970. Their statistical analyses found that a majority of these disasters occurred in the fall and winter months when the barometric pressures were influenced by unstable weather conditions and noted increased methane content in the mine workings during times of falling pressure. Studies conducted by Fauconnier (1992) and Hemp (1994) found similar connections between methane explosions and barometric pressure fluctuations in a majority of gas explosions in South African mines. Ten out of twelve major mine explosions with five or more fatalities in the U.S. after 1970 were found to have occurred during the months of November through April when barometric pressure swings were more abrupt and intense (Lolon et al., 2015)."

Jan 1, 2016

By G DeschOnes, M Fulton

The Eleonore property (James Bay district of Northern QuTbec), owned by Goldcorp, hosts gold within stockworks of quartz-tourmaline-arsenopyrite veins and veinlets contained within microcline (potassic alteration) and brown tourmaline replacement zones. The preliminary investigation to recover gold from drill core samples showed that flotation followed by ultra-fine grinding and cyanidation is the preferred option. Ultra-fine grinding is used to liberate gold finely disseminated in sulfides. The flotation concentrate used in the investigation had a P80 of 11 ¦ and contained 75.5 g/t Au, 5.0 g/t Ag, 10.3 per cent S, 0.07 per cent Cu and traces of antimony (0.03 per cent). The mineralogical characterisation showed the presence of 65 per cent gangue minerals, 23 per cent pyrrhotite (hexagonal), 9.6 per cent arsenopyrite, 2.2 per cent pyrite and 0.08 per cent chalcopyrite with trace amounts of galena (0.05 per cent) and sphalerite (0.03 per cent). Gold was in the form of native gold and electrum. A straight cyanidation conducted at pH 11.0, DO of 3 - 5 ppm, 2000 ppm NaCN, 20¦C and for 72 hours extracted 97.0 per cent Au and consumed 31.5 kg/t NaCN. The equilibrium was reached within 24 hours. Increasing the dissolved oxygen to 16 ppm reduced the consumption of cyanide to 22.0 kg/t with 96.7 per cent Au extraction. A 16-hour pretreatment with 2.0 kg/t lead nitrate, followed by a 24-hour cyanidation reduced the cyanide consumption to 6.0 kg/t with a gold extraction of 97.5 per cent. Increasing the lead nitrate addition to 6.0 kg/t reduced the cyanide consumption to 1.2 kg/t by passivating the surface of pyrrhotite. The gold extraction remained at 97.0 per cent. It was possible to decrease the concentration of cyanide to 800 ppm NaCN without compromising gold extraction. The associated cyanide consumption was 1.2 kg/t NaCN. The passivation of gold grains was an issue when the cyanide concentration was decreased to 550 ppm NaCN. The gold extraction decreased to 92.2 per cent. The average lime addition for all the tests was 7.4 kg/t and the average silver extraction was 80 per cent. Efficient cyanidation of an ultra-fine sulfide concentrate with only 800 ppm NaCN represents an advance in leaching of ultra-fine sulfide concentrates. The high addition of lead nitrate would certainly make cyanide destruction easier; consequently reducing the effluent treatment costs and making possible to meet the discharge regulations criteria.CITATION:DeschOnes, G and Fulton, M, 2013. Design of a leaching strategy to extract gold from Eleonore Mine ultra-fine sulfide concentrate, in Proceedings World Gold 2013 , pp 71-78 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By A D. T Goode

Data Metallogenica (DM) is unique as a global mineral sample collection and deposit database with over 70 000 rock samples and a wide range of descriptive, photographic and measurement data. Subscribers have access to approximately four gigabytes of on-line data with many examples included on the public pages. DM commenced its life on the Pacific rim in 1971 and much recent growth has focused on countries of the Pacific margin, particularly Australia, Fiji, Chile, Indonesia and Peru. Approximately 600 separate deposits and mineral occurrences in this region are represented in DM. The sets of rock samples have been photographed at high resolution and included on the web site, together with unpublished descriptions, deposit cross-sections, bibliographies, field and mine photographs, petrology and reflectance mineralogy. Figures and abstracts from PhD theses are a new addition and the donation of proprietary databases by companies and individuals is an encouraging trend. DM increasingly is being viewed as an acceptable and important repository for æfragileÆ and irreplaceable personal and company data, it is also being recognised in its true light as a high level information system, not solely a collection of rock samples. Data Metallogenica is a not-for-profit venture of AMIRA International that requires self-funding from December 2004. Growth and development must be funded entirely out of subscription and sponsorship revenues because no government subsidy is provided. The Pacific rim is in the mainstream of mining and exploration activities worldwide and those involved have much to gain from a dynamically sustaining DM. The home page at www.datametallogenica.com contains much example data and details of subscription and membership rates.

Jan 1, 2004

By B. L. Landrum, J. Simmons, J. M. Pinson, P. B. Crawford

Patentiometric model data have been obtained to estimate the effect of vertical fractures on the areas swept after breakthrough in water flooding and miscible displacement programs such as gas cycling where the mobility is near one, The data are presented for the case of the fire-spot pattern in which the cemer well is fractured various lengths and orientations, the data indicate that for 10-acre spacing, fractures extetidirrg over 1300 ft in either directior1 from the fractured well may re.srrlt in reductions in sweep efficiencics from 72 to approximately 34 per cent. However. the area swept after break through may be quite largr and only 10 or 12 per cent 1ess than would be obtained if the reservoir were trot fractured. For the specific case when the volume of fluid injected is equivalent to 100 per cent of the pattern vol-unie, the swent area may vary from 80 to 88 per cent, depending on the lenght of the fracture. The former value is that which occurs when the break through or sweep efficiency was orrly 34 per cent and the latter figrrre of 88 per cent is that which is obtained if the reservoir were unfrac-ttm'd. It is pointed out that although the sweep efficiency may he very low in vertically fractured five-spot patterrz.s, the area swept at low water-oil ratios may be only 5 to 10 per cent less than those achieved if the reservoir were unfractured. INTRODUCTION Since the initiation of commercial reservoir fracturing techniques it has been desirable to determine the effect of fractures on the areas swept after breakthrough. Most water flooding or gas cycling projects are continued for substantial periods after the brcakthrough of the injected fluid. Although the sweep efficiency serves as one criterion for rating various flooding patterns. the area swept after breakthrough for various water-oil ratios or percentage wet gas, if cycling. is of perhaps more importance than the sweep efficiency alone. Sweep efficiency data on the vertically fractured five-spot have been presented3. Previous work on the line-drive pattern has shown the effect of vertical fractures on the area swept after breakthrough for the case in which the distance between injection and producing wells divided by the distance between adjacent input wells was equivalent to 1.5 (see lief. 2). The data indicated that for the line-drive pattern it may be desirable to flood or cycle substantially perpendicular to the fractures in order to achieve the greatest recovery for the smallest volume of fluid injected. For this study the center well of a five-spot is assumed as the fractured well. All fractures were assumed to originate at this well and extend into the reservoir for various distances and orientations. All the fractures are straight and are of large permeability compared to the matrix proper. These data are presented to aid the engineer in estimating fractured five-spot pattern performance. ANALOGY The potentiometric model was used in making this study. The model used was 20 20 in. by approximately 1-in. deep. For certain portions of the study one corner of this model was considered to be an injection well and the opposite corner a production well. To simulate vertical fractures a copper sheet was soldered to the wire well and made to conform to the desired length and orientation. In other studies the same model was used except that the four corners of the model might be considered as the corner wells of a five-spot pattern and a fifth well was placed in the center of the model. The well placed in the center of the model was fractured. The total fracture length is L and the well spacing. d. The complimentary fracture angles will be obvious from Figs. 3 and 4. The data obtained on the potentio-metric model assumes the pay to be uniform and homogeneous, the mobility ratio is one, steady-state conditions exist and gravity effects arc neglected. The permeability of the fractures is very great compared to that of the matrix proper. The po-tentiometric model has been used widely both in water flooding and gas cycling projects, and may be used for miscible displacement; how-ever. it is believed that the poten-tiometric model data are more properly applicable to gas cycling than water flooding because the model as-

By H. Dale Nichols

[The growing importance of the Sundence (Jurassic) formation an a source of oil, in the Rocky Mountain area has prompted the making of a series of porosity determinations of core samples collected. from the reservoir sands of the Lance Creek oil field, Niobrara. County, Wyo. These analyses are preliminary to a stud of fluid and energy relations in the Basal Sundance reservoir of that field, and the determinations of porosity will be used in subsequent studies requiring, calculations of the volumetric capacity of the reservoir and estimation of the reserves of oil and gas. However, the porosity characteristics an of the Sundance sands in the Lance Creek field are factory that affect the solution of many current practical problems of development and operation. Primarily for that reason but also because it is recognized that porosity values of different oil-production sands are of widespread interest throughout the industry, the results of the initial work have been presented in tabular and graphic form with no attempt to evaluate their significance as they relate to the production history of the field.]

Jan 1, 1938

By K. E. Hjelmstad, W. H. Pomroy

In the event of fire underground, it is essential that all miners be warned as quickly as possible. With mine air rapidly depleted of oxygen and contaminated with smoke and toxic fire gases, any delay in the warning signal could have disastrous consequences. Unfortunately, present mine fire warning systems, such as stench, audible or visual alarms, telephones, and messengers, are often slow, unreliable, and limited in coverage. Recent research by the US Bureau of Mines has established the feasibility of ultralow frequency electromagnetic signaling for underground mine fire warning. Infield testing completed thus far at five mines, signals of from 630 Hz to 2000 Hz were transmitted through rock up to distances of 1645 m (5400 ft) to a pencil-sized ferrite-core receiving antenna and intrinsically safe receiver circuit. Theoretical analysis indicates a capability to transmit effectively for distances in excess of the maximum depths of most American mines, which is about 900 to 1000 m (2950 to 3280 ft) . The prototype system uses off-the-shelf components and state-of-the-art technology to ensure high reliability and low cost. This technology would enable simultaneous and instantaneous warning of all underground personnel, thereby in- creasing the likelihood of successfully evacuating a mine during a disaster. This report discusses the theoretical basis for through-the-rock ultralow frequency electromagnetic transmission, design of the prototype transmitter and receiver, and the results of in-mine tests of the prototype system.

Jan 1, 1991

By Raúl Hidalgo

El presente trabajo describe el plan estratégico de la mina San Vicente, ubicado en la provincia de Chanchamayo, departamento de Junín. Entre los objetivos de la mina está el aumento de la productividad a través de la reducción de costos de operación y realizar labores de pre-minado de 20 m/ día en los avances de operaciones. En este sentido, si bien la función del mecanizado es importante para el incremento de la productividad, es necesario controlar y administrar los recursos del nuevo yacimiento. Por ello, para implementar la nueva tecnología del minado es necesario el estudio de mecánicas de rocas y asi determinar la característica de la masa rocosa y la factiblidad económica para excavados mediante el sistema de minado contínuo.

Aug 26, 1988

By J. S. Brock

Magnetic, electromagnetic and gravimetric surveys have played an important role in the mineral exploration leading to the discovery of three major massive sulphide deposits in the Anvil-Vangorda area of the Yukon Territory. During 1964 and 1965 a saturation prospecting program, relying heavily on the integrated use of airborne and ground geophysical survey techniques, led to the discovery of the Faro deposit, which was subsequently proven to be a 63-millionton lead-zinc orebody. Locating the Faro deposit, the largest found to date in this overburden-covered region, involved an exploration sequence requiring the selection of a favourable geologic environment, aeromagnetic and electromagnetic surveys, property acquisition of anomalous areas and detailed ground geophysical surveys, followed by rotary drill testing, detailed gravimetric surveys and diamond core drilling.

Jan 1, 1973

By D. J. McLaws

"Recent innovations in metal smelting technology utilize continuous oxygen-enriched smelting and converting processes which are capable of producing off-gases containing up to 60% SO2 or more. Other SO2 recovery processes, involving solvent absorption and steam or vacuum regeneration, can produce off-gases with SO2 concentrations nearing 100%.Processing of these high-concentration SO2 off-gases in conventional sulfuric acid plants can cause excessively high catalyst bed temperatures and poor SO2 conversion. In order to avoid these problems, a conventional acid plant design must dilute these high SO2 process gasses with dilution air in order to provide the required oxygen to effectively convert the SO2 and provide a heat sink (via the inert N2) such that the exothermic reaction, SO2 + ½ O2 ???SO3, does not exceed the temperature limit of the catalyst or the converter vessel.MECS, Inc. (MECS) has proven that a high SO2 feed gas design can be a viable option which can increase energy recovery, reduce energy consumption and potentially reduce capital costs."

Jan 1, 2014

By Francis Church Lincoln

"INTRODUCTION During the period from September 18 to November 27, 1944, the Bureau of Mines conducted an investigation and exploratory churn-drilling program in an area immediately north of the Crow Branch Diggings, a district lying approximately 2 1/2 miles southwest of the town of Livingston in Grant County, Wisconsin.The work was undertaken as part of a general Bureau of Mines investigation of the zinc-producing area of southwestern Wisconsin at a time when all effort was being made to increase the production of metals important to the Nation's war prrgram.Although no mining has been done in the district in recent years the Crow Branch Diggings were an important source of galena and may be found today in the dumps remaining from old surface-mining operations.The Bureau of Mines undertook an exploratory churn-drilling program on the northwestern projection of the general strike of the digging in a zone where subsurface,lead and zinc mineralization had been reported from drilling done in the early 1900's."

Feb 1, 1947

By Hsu-Hui Hsing

In several previous studies from this laboratory (1-4) the autophobicity concept of Zisman and co-workers (5, 6) has been extended to gas phase adsorption processes. Low molecular weight alcohols adsorb on silica or alumina to yield novel isotherms in that monolayer adsorption occurs at low relative pressures indicative of strong bonding, but subsequently multilayer adsorption is quite sparse and diminishes with molecular weight of the alcohol. Such isotherms fit no standard classification scheme, however, in the vacinity of monolayer coverage alcohol isotherms give an excellent fit to the Langmuir or B. E. T. , Type I model (7). Monolayer adsorption is relatively irreversible and it is thus possible to prepare these chemisorbed layers and perform subsequent adsorption studies thereon. All indications are that the adsorptive properties on such films is radically different from that on the underlying alumina (4, 8) and in one study finite contact angles for hydrocarbon fluids were observed. One perennial conceptual difficulty is that there is no observed upper bound to the adsorption isotherm which would be necessary for autophobic adsorption to occur. The cause for this has been studied, and it is currently believed that adsorption is complicated by reversible capillary condensation at contact points between powder particles. The evidence for this is that large particle powders give less "apparent" adsorption at high relative pressures and in one very tedious study adsorption on planar sheets, oxidized aluminum displayed similar reduced uptake at high relative pressures when compared with high specific surface area powders (3).

Jan 1, 1974

By Roger K. M. Bellows

The last coal-fired power plant to be built in Canada came into operation in 1994. Since then, Canada?s electricity requirements have grown substantially but no new coal-burning plants have been built. This country has abundant resources of coal from coast to coast, but in recent years, this has not affected our choice of fuel. In many other countries this is not the case, and the use of coal is growing rapidly. Although this presentation covers the topic from an Alberta perspective, some of the conclusions can be extrapolated to the rest of the country, and perhaps even to other countries. The coal found in the Alberta plains is particularly attractive because of its low cost and low sulphur content. Yet coal is no longer the fuel of choice, and a long-standing provincial government policy to favour coal for electricity generation has been ignored for more than a decade. Considering the lack of good alternatives, it seems obvious that we should look to coal as our primary energy source in the generation of electricity and for other industrial applications. This paper discusses some of the reasons that coal has fallen out of favour, particularly with respect to electricity generation. The significance of the deregulation of the electricity industry will not be ignored. In addition, the author will offer his opinion on the question of what it will take in order for coal to once again become the favoured fuel.

May 1, 2001

By Jan M. Mutmansky

A knowledge of rock characteristics forms the foundation for the application of rock mechanics to engineering works. Hence, there has been an increased interest in the determination and proper utilization of rock properties data. Most numerical values quoted for rock properties are obtained from arbitrary tests and are not necessarily indicative of any intrinsic rock characteristics. Recent attempts to correlate these properties by statistical methods have attracted considerable attention, in the hope that these might give some clue to the fundamental properties. To date, correlation and regression techniques have been employed for this purpose. The use of statistics has also been deemed appropriate because of inhomogeneity and anisotropy in rocks. The problems have been further compounded by the lack of standardized methods of measuring rock properties. The various ASTM committees are still deliberating on these matters, but recommendations should be forthcoming in the near future. As more reliable data become available, the ability of geoscientists to find more meaningful relationships between rock properties will be greatly enhanced. The objective of this paper is to outline another statistical technique which might be useful in providing an insight into the relationships that exist between rock properties. This method does not attempt to predict rock characteristics, but rather compares the similarity or dissimilarity between properties. This enables rock properties to be classified into groups with similar intrinsic characteristics. The technique described is one form of factor analysis. It allows the results obtained to be depicted geometrically, so as to make ready visual examination possible.

Jan 1, 1968

"Geoscan is used for multi-elemental analysis of conveyed bulk materials in the minerals industry with proven performance and demonstrated paybacks of weeks or months in iron ore, manganese, copper, zinc-lead and phosphate industries. Geoscan-M measures continuously through the full bed depth and is unaffected by belt speed, particle size, layering, mineralogy and dust levels. Increments of typically two minutes are accurately measured and provide the plant operators with tonnage weighted results of contained elements. Measurement of the composition in real time enables prompt feedback to the mining operators and also feed forward to the process operators. Crushed ore increments can be diverted based on composition, such as diverting waste for disposal or marginal material to a stockpile for separate processing. Bulk sorting allows material to be placed into relevant stockpiles for subsequent blending to achieve consistency for process feed. Parameters used for decisions may be primary metal content, deleterious component content, other process parameter, or a combination of these. Process parameter may be the elemental ratio between critical components, e.g. Cu:S ratio, basicity, or the content of an “indicator” element (such as Si indicating material hardness). Benefits will be discussed based on case studies in copper and iron ore.IntroductionAs operators of process plants strive to remain competitive as capital and operating costs increase and commodity prices fluctuate, more focus has been directed at incremental performance improvements at incremental cost rather than major expansions to increase output. The philosophy of working smarter allows plants to adopt technologies proven in other industry sectors to minimise risk. This paper discusses one such technology that the minerals sector is adopting and has found to be safe, reliable and accurate with paybacks of weeks in most applications. New applications continue to be found and major benefits realised at various stages in the processing and handling of ores and products."

Jan 1, 2016