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By T. G. Joseph

"The Oil sands-Equipment Interactions Program (OsEIP) is a collaborative research venture between Syncrude Canada Ltd., James Progithin International Ltd. (JPi), the University of Alberta, P&H MinePro, and Caterpillar Inc. The objective is to better understand the behaviour of oil sands as it interacts with mining equipment, in particular, large trucks and shovels. With a move to ever larger equipment, mining oil sands of highly variable bitumen content, ground stability comes into question. This paper outlines this aspect of OsEIP and provides some insight into how some of the findings enable an improved understanding of oil sands behaviour that may impact large equipment design, operational and maintenance strategies. IntroductionThe mechanical behaviour of oil sands in the underfoot and in the face yields some of the harshest stability and digging conditions of any mining environment. High maintenance costs from truck and shovel fatigue failures predominate as a result of ground stability issues. Wear rates of shovel and dozer ground engaging tools (GET), rollers, roller paths and crusher screens result in costly and frequent replacement, or even more frequent and costly sacrificial wear zone building. From the shovel face to the crushers and screens, dry oil sands mechanics affects the degree of fragmentation and, ultimately, bitumen production.An increased knowledge of the behaviour of oil sands with respect to stability, fragmentation and abrasion, etc. would enhance the long-term equipment design process at the vendor level, and provide the end user with improved short-term operational guidelines and long-term strategies for future purchases and operation. Truck vendors recognize that the interaction between operator, seat, frame, suspension, tires and oil sands is unclear, and must be better understood before proceeding to next generation designs. Similarly for shovel manufacturers, the relationship between bucket/dipper motion, carbody, side frame, rollers, track and oil sands follow in the same vein."

Jan 1, 2002

Currently an Australian Standard for tunnel fire safety is being developed for road and rail tunnels. Other local guidance relating to tunnel fire safety that has recently become available includes publications by both the Roads and Traffic Authority and RailCorp of New South Wales. Internationally, the World Road Congress has completed its 2004 - 2007 cycle, which has resulted in a number of publications. International developments in rail guidance include a new European Standard regarding fire safety in railway tunnels that will come into effect in July 2008. In addition, the National Fire Protection Association committee NFPA 130 are in the process of revising their standard for fixed guideway transit and passenger rail systems, which is due for publication in late 2009. This paper outlines the status of these and other recently published relevant local and international fire safety guidelines and their implications for tunnel projects in Australia.

Jan 1, 2008

By John J. Mulligan

Coalbeds were discovered in outcroppings of the Beacon group of sediments on the north end of the Willett Range ( altitude 77 ° 11 ' S , longitude 160 ° 20 ' E ) , Victoria Land , Antarctica , in December 1960 during an investigation undertaken as part of the U.S. Antarctic Research Program under the auspices of the National Science Foundation . Three separate exposures of coal or coaly material were found . Two of the exposures contain , respectively , eight and four beds of hard , compact , finely banded attrital coal ranging in thickness from 8 feet downward to a few inches , and reported to range in rank from mediumvolatile bituminous to semianthracite . The coals are associated with carbonaceous shales containing an abundant assemblage of fossil plants resembling those associated with the Permian coals of Australia and other Gondwana areas . The third exposure , apparently somewhat higher in the stratigraphic sequence , contains only coaly plant fragments scattered through a thin conglomerate and overlying sandstones . A sandstone bed that overlies these coal - bearing sandstones contains abundant logs and fragments of silicified wood . Preservation of features is poor , but one segment of a silicified stem suggests comparison with Rhexoxylon , a gymnospermous tree that usually is considered indicative of Triassic age . The Beacon sediments in this area have been invaded , broken , and uplifted by a massive series of diabase sills and dikes greater in volume than the intruded sediments . The heat emitted by these intrusives must have advanced the metamorphic development of the coals . However , there is no evidence of alteration to graphite , and coal found in direct contact with a diabase sill contains no vesicles or other usual evidences of natural coking . Either the pressure of overlying rocks inhibited the development of coke , or the coals had been metamorphosed beyond the coke forming stage before the igneous intrusion .

Jan 1, 1963

By Nikolaos Polysos, Holger Witthaus

INTRODUCTION The classification system for German coal mining is the result of approximately 100 years of experience in roadway development and longwall mining. It is also based on different research projects covered by national and European research programs. Over the past 30 years, more then 600,000 m of road-ways have been driven and employed for mining activities. To properly describe the German rock mass classification system, therefore, it is useful to take a look at the main geomechanical preferences and common support systems. The decision about the most effective development technique and support system is based on a synthesis of rock mass classification and geomechanical analysis. The properties of surrounding rock, the in situ stress, and the influence of mining activities in several seams at each German mine must be considered for the evaluation of the expected deformation of the roadway. The mine layout, the requirements of ventilation and fire prevention, as well as the need to maintain emergency escape routes for the miners, require that the gate roads remain usable after the passage of the longwall face in most cases. Moreover, the gate roads must be maintained despite the high stresses that are applied during longwall retreat mining. Therefore, gate road design must address a broad spectrum of potential deformation environments. In the past, when gate roads were supported solely with yielding steel arches, lithologic descriptions of the surrounding strata conditions were adequate for the dimensioning of support and the prediction of the roadway deformation. The current conditions of multiple-seam mining at depths of up to 1,700 m require combined support systems, including pattern bolting and backfilled steel arches. Rock bolt support is used for development, after which (typically 50–100 m outby the face) the steel arches are installed and backfilled with building material (concrete) in order to achieve an optimized development rate. The rock mass classification system described below was developed especially for the conditions of German hard-coal mining. It includes the stress distribution caused by multiseam workings (including crossing goaf edges of former longwalls), as well as in situ stresses due to greatdepth and the presence of tectonic faults. It is based on the evaluation of four parameters: • Geotechnical analysis of drill cores • Geotechnical observation of the development face • Geotechnical classification of tectonic structures (faults) • Standard classification derived from geotechnical assessment and evaluation of stress conditions (using numerical modeling for stress calculation) ROCK STRENGTH One of the most important input parameters for describing strata conditions is the strength of the rock. The German classification system is based on a description of lithotypes. This method has been used successfully since the 1950s and is based mainly on the uniaxial compressive strength (UCS) of the material. An evaluation of the rock strength observed in a survey of approximately 82,500 samples of rock core yielded the results shown in Figure 1. The three most common coal measure rock types are mudstone, siltstone, and sandstone. Each shows a specific mean UCS level and a different spread between the minimum and maximum values. Sandstones, in particular, have a wide spectrum of compressive strength, ranging from approximately 40 MPa to greater than 130 MPa, with an average of 85 MPa. The causes of this wide range include different sedimento-logical preconditions, facies, and digenetic processes. [ ]

Jan 5, 2007

By John V. Beall

Early this year at the University of Arizona in Tucson, a survey was made of student opinion about the minerals industry. Over 100 of the three page questionnaires were completed and these were analyzed by the following categories: 40 Mining Engineering students, 20 Geological Engineering with 2 Geophysical Engineering students, 15 Geology students, 7 Metallurgical Engineering, 26 Underclassmen, 29 Graduate students and a composite of 84 total students. Not all of the results of the survey were predictable. After graduation there is a strong preference toward going to work in the mineral industries. The next most popular options, but trailing the first choice greatly, was graduate work or employment in another industry. A smattering of other choices were for teaching, government or research. None checked the box for drop out.

Jan 1, 1971

By Fred S. Karn

Inhibitors are used in coal mines as a precaution against accidental dust explosions. Although rock dust is the usual inhibitor many others have been tested. To facilitate testing a screening process using laser irradiation was proposed. The procedure includes irradiation of a coal-dust mixture followed by mass-spectrometric analysis of the evolved gases and an evaluation of the flammability characteristics of the gases. Carbonate-type inhibitors decreased the percentage of combustibles in the gases generated and inhibitors like NaCI (thermally stable salts) decreased the total gas generated. A suitable test procedure did not result from the investigation, demonstrating the inadequacy of fast heating, non-combustive techniques in rating inhibitors of coal dust explosions.

Jan 1, 1973

By F. R. Hutto Jr., F. L. Kady Jr., L. E. Weymouth

The behavior of particulate non-metallic materials in moving contact with smooth surfaces is of interest and concern to manufacturers and users of abrasives, of fillers, and of pigments alike. The theoretical aspects of the subject have been treated to considerable extent in the literature, and correlatic,ns are available that attempt to relate various methods of hardness determination." 2 The particle size and friability are characteristics of the abrasive that are not related to the smooth surface. The hardness, on the other hand, may be visualized as relative to that of the smooth surface. In a study of abrasive action, the role that hardness, per se, plays is a complicated one. For it is necessary to compare the "hardness" of the abrasive, usually a non-metallic, with that of the smooth surface, generally a metal. Hardness of non-metallics is defined as resistance to scratch and is almost universally described with respect to the Mohs scale.3 Minerals have been rated by Mohs numerically from the softest (talc = 1) to the hardest (diamond = 10). By definition, a mineral has a designated hardness when it is scratched by the standard that is numerically just above it on the scale; and conversely, when it scratches the standard that is just below it. Hardness of metals. however.. implies resistance to indentation, a property that has been measured by a number of methods. In fact, the indentation hardnesses of the standard minerals on the hlohs scale have been determined by the Rockwell tester. Reproduced below are two versions of this correlation. 'A conversion chart, prepared by Wilson Mechanical Instruments Division of American Chain and Cable Co., merely gives the conversion from Rockwell to Knoop hardness. The relation between Knoop indentation hardness and Mohs scale has been reported by G. S. Smith — A New Scale of Hardness, The Engineer, Aug. 26. 1949. G. F. Kinney in Engineerin Properties and Aplications of Plastics reports the Rockwell hardness of the minerals directly in the Mohs scale. The question immediately arises as to whether this relation is valid when applied in reverse; namely,

Jan 1, 1961

By H. Yin, T. Emi

"Advantages of gas/flux injection technology as materialized in the main stay unit processes for steelmaking are depicted covering hot metal pretreatment through secondary refining. Current status of micro-kinetic issues involved in the injection technology are reviewed including gas-in- metal, gas-in-slag, flux-in-metal, metal-in-flux and three-phase dispersion systems with reference to macro-kinetics. Key problems are briefly addressed to further develop injection technology for steelmaking processes.1. FROM PAST TO PRESENTApplication of gas injection to steel industry started in early 1950's when inert gas bubbling via stopper rod, lance, or porous refractory plug was practiced to make the temperature of steel melt in ladle uniform The gas bubbling in ladle was then extended to slightly removing hydrogen ti'om the steel melt tapped from Electric Arc Furnace (EAF) and Basic Open Hearth Furnace (BOH) when vacuum processing facilities were not popular. Later, oxygen gas injection via calorized steel pipe into molten steel bath in BOH Furnace was also put into operation to promote the decarburization to increase the productivity of the process. This line of development has been made in parallel with more profound processes, i.e, top blowing Basic Oxygen Furnace (BOF) for primary steelmaking and side blowing Argon Oxygen Oecarburization (AOD) vessel for decarburizing stainless steels.On the other hand, injection of fluxes into steel bath was first industrialized in Germany in 1960's, Primary objective was to desulfurize steel melt in ladle by injecting CaC2 or CaCrCaO mixture via lance under neutral slag cover with good success. Difficulties in injecting fluxes without clogging and rippling at a desired flux/gas ratio, and durability of injection lance were resolved in due time to bring forth many injection facilities to flourish for versatile refining operation. Top injection of fluxes from main oxygen lance to BOF was also industrialized as LDAC to promote early slag formation. A new process then emerged which injects oxygen gas and fluxes together through concentric annular tuyere, installed at the bottom of the BOE into steel melt. This process, developed in Germany [Oxygen Bottom Maxhutte (OBM)] and brought into maturity in USA (Q-BOP) and Japan in a large scale operation, became the predecessor of the combined blowing (top and bottom blown) BOF which dominates modern steelmaking."

Jan 1, 1996

By Osamu Taki

The development of new auger bits for soil cement column drilling equipment has made it possible to create a homogeneous mixture of soil and cement-reagent slurry. As a result, soil-cement columns are used for foundations of houses and buildings, with reliable results, as demonstrated by many field projects and laboratory tests. This paper presents and discusses construction techniques for soil-cement columns, characteristics of the soil-cement solid, quality control, bearing test results, and soil-cement foundation design procedures.

Jan 1, 1992

By Won C. Park

Experiments showed changes in the mineral content of dolomitic oil shale at temperatures and exposure times which bracket conditions encountered during in situ retorting. Laboratory results correlate with cores from a spent in situ retort at Occidental's Logan Wash test site at Garfield County, Colorado. Dolomite, CaMg(CO3)2, decomposes rapidly to form periclase, MgO, calcite, CaCO3, and CO . Both calcite and periclase are intermediate products that can be stabilized by CO atmosphere at lower temperatures, while steam accelerates the formation 2 of silicates. The decarbonation of calcite appears to involve a direct reaction with both quartz and periclase in forming these silicates. Decarbonation preceeds the formation of akermanite, Ca2 MgSi 207, and diopside, CaMgSi 206, within several hours of heating and is followed by the nucleation of forsterite Mg2SiO4, and monticellite, CaMgSiO4. Under in situ retorting conditions, akermanite and diposide are the major minerals above 800°C. Equilibrium is not attained within 200-300 hours. In situ retorting temperatures above 800°C for extended periods of time should reduce potential ground water leaching by the formation of silicate minerals. These silicates are less soluble than free lime, magnesium or alkali oxides. There is a corresponding decrease in the natural pH of these silicates from approximately 12 down to 7.5 to 9:

Jan 1, 1981

By Remo Grandori, Manfred Jaeger, Fabrizio Antonini, Luis Vigl

The EVINOS-MORNOS tunnel project with its 30 km of length is one of the longest hydraulic tunnel in the world realised with TBM method. The adverse geological conditions, the high cover and the short construction schedule were a great challenge for the successful construction of this tunnel. The paper will describe: the criteria adopted for the tunnel design, the selection of the construction methods and equipment, the productions of the 4 TBMs adopted and the comparison of the behaviour of the different type of TBMs in the various rock conditions, including special conditions, the characteristics of the adopted in situ and precast linings, a comparison between the foreseen and actual construction schedules, the contractual implications of realising a tunnel in such a severe and complex conditions.

Jan 1, 1995

By Richard L. Fischer

Constant-volume charges of precipitated PETN (pentaeythrite tetranitrate) at three specific gravities (0.50, 1.00, and 1.50) were used in laboratory tests to examine the effects of changes in explosive properties on free-surface displacement pulses and on crater dimensions. The tests were performed in large blocks of cement-mortar. The values for the detonation velocity, detonation pressure, specific energy, energy density, and energy release rate were calculated from the explosive loading density. Calculated explosive properties were correlated with free-surface displacement pulse measurements, strain energy, and measured crater dimensions. Increases in explosive properties resulted in increased free-surface displacement pulse parameters and crater dimensions. The loading density, detonation velocity, energy density, detonation pressure, and energy release rate were found to be best indicators of explosive performance. Simple acoustic relationships involving impedance ratios were examined and could not be used to predict peak displacement amplitude or strain energy. Data are presented in the customary English units as well as the International System of Units (SI).

Jan 1, 1970

The Dizon open pit mine of Benguet Corporation in western Central Luzon, Philippines has yielded some 182 000 t copper, and about 26 000 kg gold and 48 000 kg silver as by products since it started operation in November 1979. The 140 million tonne orebody is associated with a small quartz diorite porphyry stock emplaced in volcanic rocks on the basal slope of a stratovolcano complex as stockworks, fracture fillings and disseminated sulphide mineralization averaging 0.43% Cu, 0.93 g/t Au and 2.5 g/t Ag. Intense hydrothermal alteration accompanied the mineralization that developed fairly distinct mineral assemblages within and around the intrusive. Post-ore volcanic activity later gave birth to an upward-flaring diatreme which broke out south of and adjacent to the orebody and partially destroying it. Subsequent volcanic activity buried the mineralized area along with the rest of the stratovolcano's surrounding slopes under a thick deposit of pyroclastic and laharic debris. Erosion eventually removed the volcanic cappings over Dizon and also exposed the quartz diorite porphyry stock which might have resulted in the truncation of a sizeable section of the Dizon deposit. The chain of stratovolcanoes that comprise southeastern Zambales range hugging the southeastern edge of the Zambales ophiolite is part of a west-facing volcanic arc that extends for some 300 km along the western margin of central and southern Luzon whose development has been correlated to the subduction in the Manila Trench located off the west coast of Luzon. Prominent WNW-trending lineaments that cut across the ophiolite appear to be splays of the Philippine Fault whose intersection with the Mt. Pinatubo stratovolcano complex might have localized the emplacement of a number of intermediate stocks along with the gold-rich porphyry copper mineralizations associated with some of them.

Jan 1, 1987

By Edwin G. Sharp, Frank S. Gaunce, George M. Freeman, Denis J. Kemp, Eric Dulson, Paul Salmon, Ernest R. Hamilton, Carl E. Parden

"THE ECSTALL ZINC PLANT was built for the treatment of the Kidd Creek zinc sulphide concentrates. Construction proceeded throughout 1970-71, with operations beginning in April 1972. The two concentrate types treated differ principally in minor impurity and precious metal contents. Processing flexibility was required to allow efficient recovery of the by-products, especially cadmium, copper and silver. The conversion of the zinc sulphide concentrates to end products follows a sequence of operations that are common to most electrolytic zinc plants and typical of the ""Tainton- Jephson"" flowsheet.1. Roasting in air at an elevated temperature to convert the metal sulphides to soluble metal oxides (calcine) and sulphur dioxide. The sulphur dioxide is converted to sulphuric acid in a contad plant and shipped by train to market.2. Leaching of the calcine in spent electrolyte to effect extraction and recovery of zinc as zinc sulphate solution, leaving an insoluble residue.3. Purification of the clarified zinc sulphate solution by cementation with metallic zinc dust to remove impurities detrimental to the electro-deposition of zinc or detrimental to product purity. The solids from cementation are the starting materials for secondary metal recovery.4. Electrolysis of the purified zinc sulphate solution to reduce the zinc to the metallic state while coincidentally regenerating the sulphuric acid for recycle to the leaching step."

Jan 1, 1974

By Greisson Peixoto Rangel

A variação da resistência à compressão de argamassas geopoliméricas foi estudada em função da razão ativador/precursor e da molaridade da solução ativadora. As argamassas estudadas foram confeccionadas com metacaulim (precursor) ativado com solução composta por hidróxido de potássio e água destilada, e areia normal brasileira. De acordo com os resultados, a resistência aumenta com a diminuição da razão ativador/precursor e com o aumento da molaridade da solução ativadora. Além disso, os valores encontrados condizem com os presentes da literatura e com possíveis aplicações para argamassas de múltiplo uso.

Oct 30, 2017

By Albert L. Toenges

The introduction of mechanized mining in coal mines, which has speeded loading, has emphasized the importance of efficient underground transportation systems. The purpose of this investigation is to study and analyze various systems now in use, and to derive conclusions therefrom. This report may be helpful to operators who are planning new systems of transportation or who are revising present systems to increase their efficiency. This paper is the first of a series on this subject and describes some systems of transportation utilizing rail haulage. ACKNOWLEDGMENT The information used in preparing this report was obtained through the courtesy and cooperation of the officials of the companies whose mines were studied. The descriptions of the transportation systems at the mines included herein have been checked for accuracy, and publication of the data has been approved by the executives of the several operating companies.

Jan 1, 1940

The importance of understanding the behaviour of cemented paste backfill (CPB) within the framework of the effective stress concept is highlighted in this paper. Only through an understanding built on this concept can problems such as barricade loads, the rate of consolidation and arching, be fully understood. The critical importance of the development of stiffness during the hydration process, and its impact on factors such as barricade loads, is used to illustrate why conventional approaches that implicitly ignore the effective stress principle are incapable of capturing the essential components of CPB behaviour.

May 1, 2007

By Joanna LaForte

"In response to “Arctic Mineral Wealth —Equitable Participation with Aboriginal Landowners – A slow or fast process?”, this author’s impression is one that, to her, seems obvious — this is definitely going to be a slow process. To question this issue seems ridiculous, unless the mining industry is considering following the same patters of the past, thereby adding to the suppression and injustices to which the aboriginals are so accustomed. To make genuine progress, where trust and good communication has been achieved with time as a factor in proceeding, the author feels, without a doubt, that the triangle of industry, government and aboriginals will seriously have to be restructured or eliminated. Anytime you mix government with progress, along with other problems, you are looking at bureaucracy, and that takes time. Issues such as the settlement of land claims have not been resolved, and in all likelihood could take forty years to finalize. Aboriginals have been suppressed for centuries by governments and industries with ethnocentric ideologies, and now that they are in a position to reclaim their lands, attain their own economies and government, and truly secure a wealthy, self-sufficient legacy for their descendants, how can anyone imagine they’ll move quickly? This author also strongly disagrees to some sections of Mr. Wakefeld’s article and will expand on her objections.We question whether aboriginals under-stand the process of mine development. If we encounter an electrical problem in our home, o we not call an electrician without having to learn the trade ourselves? This comparison seems simplistic, but does convey a point. As cited, “there are now over 100 000 aboriginals who have completed post-secondary education.” Are the numbers revealed in Mr. Wakefeld’s paper there to scare us? Is he suggesting that without the industry’s haste, the aboriginal’s new found intelligence could pose a problem to the mineral explorer. While it is true that not all are highly educated, the aboriginals have specialists in market fluctuations, feasibility studies and the needed skills. They have specialists, such as their representative organization of COPE 1984, (the Committee for Original People’s Entitlement), who under-stand their cultures, language and desires. Their education should expedite the negotiations and end the power struggles equitably. Aboriginal people are not stupid. Once they have reason to be proud, regain their communities and know the direction that they’re headed, their self-determination will return."

Jan 1, 1996

By Eugene H. Skinner

The U.S. Bureau of Mines conducted experiments on the use of lightweight concrete in the density range of 100 Ib/ft3 for liners in underground mines. Three test sections were completed: a monolithic, portal-type structure with integral walls and arch constructed aboveground; an underground test section constructed in a mine drift using plywood forms; and a second section constructed in a drift using an air-supported formwork. The lightweight concrete in the two underground test sections was placed using piston pumps and a slickline. Fiber reinforcement was added to the concrete in the mine sections without any apparent problems with either pumping or placement of the concrete. In another experiment, the Bureau and Hecla Mining Co., Mullan, rD, used lightweight concrete in the density range of 25 Iblfe to replace timber blocking in a raise preparation structure. Other experiments are described in which low-density, lightweight concrete blocks were produced for mine ventilation doors, stoppings, and barricades. Other mine uses reviewed include pillars and collapsing beams. An advantage of low-density concrete is that it will display up to 50% deformation at a constant yield stress. These hlllovative concepts in deformable concrete lining systems will aid mine operators by decreasing capital and maintenance costs, increasing the available space in underground haulageways, and providing productivity gains and improved resource recovery in the soft, caving, squeezing, or bursting grollnu conditions often found in deep mines.

Jan 1, 1989

By R. K. Singhal, H. Sahay

Introduction In terms of the world's recoverable coal reserves, Canada ranks 10th, providing 0.6% of the world's total. The US is first with 27.8% and the Soviet Union follows with 24.1%. Figure 1 shows the principal coal mines in Canada. Several provinces contain substantial coal deposits, but the largest deposits are found in the western provinces of Alberta, British Columbia, and Saskatchewan. Conservatively, 90% of the lignitic, 80% of high volatile bituminous, and nearly 100% of subbituminous, and low and medium volatile bituminous coals are located in these three provinces. During the past decade, Canadian coal production of all types increased from 18.8 Mt (2 million st) in 1972, to 25 Mt (28 million st) in 1975, to 61 Mt (66 million st) in 1984. About 38 Mt (43 million st) of this output was classified at thermal and 23 Mt (25 million st) as coking and metallurgical coal (Table 1). The three western provinces currently produce 57 Mt (62 million st) of coal - 95% of Canada's total. The remaining 3.6 Mt (4 million st) (5%) is produced in Nova Scotia and New Brunswick on the east coast. The majority of western coal (98%) is produced by surface mining methods. On the east coast, though, mining is predominantly underground and only 15% is produced on the surface. In 1985, Canada exported close to 28 Mt (30 million st) of metallurgical coal and thermal coal. During the same period, 15 Mt (16 million st) of coal were imported, mostly from western US for use in Ontario and Quebec. Almost 60% of the imported coal was used for thermal applications. The remaining 40% was metallurgical coal for the steel industry. It is generally cheaper to import coal into central and eastern Canada from the eastern US to augment local supplies rather than from western Canada. This is mainly because of high transportation costs. Mining methods The suitability of mining methods in a particular area depends largely on the geological setting. Geology, therefore, simplifies or adds complexities to mining operations, directly affecting the economics. It also influences the flexibility required from the min-

Jan 9, 1986