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By S. R. L. Harding

"Introduction0N MAY 2th, 1953, Socony Seaboard Pembina No. 1 well, located 70 miles west-southwest of Edmonton, was completed as a producer of high-gravity oil from the Cretaceous Cardinm sand. This event is possibly the most significant in the development of the oil industry in Western Canada since the Devonian discovery at Leduc in 1947. The result of the Pembina discovery and the follow-up drilling has been a tremendous increase in interest in the Cardium formation.Descriptions of the Cardium formation, as it occurs in the 'Central Foothills' and in the 'Southern British Columbia Foothills' have been presented by R. E. Folinsbee (9)-and C. R. Stelck (21), respectively. The purpose of this paper is to discuss the more regional aspects of the subject.The name Cardium was first used .as a stratigraphic term in 1863. Dr. James Hector ( l2), geologist attached to Captain John Palliser's exploratory expedition, gave the name 'Cardium to the whole section of marine Cretaceous beds exposed along the Bow river west of Calgary."

Jan 1, 1955

By G McKay, M Erskine, S Macklin

The City of Sydney is currently investing in a number of infrastructure projects that require tunnel excavations within the Triassic Hawkesbury Sandstone. It is generally accepted that this formation has high residual stresses of ‘tectonic’ origin, so much so that these stresses have been implicated in a number of well-known failures and problems for tunnelling. These include failure of ‘roof beams’ comprising discrete beds in the crown of tunnel excavations; stress-induced spalling and ‘slabbing’ of tunnel walls; shear displacement between beds causing the failure of rock bolts; strain in adjacent infrastructure and, the necessity for re-grouting of high conductivity fractures due to stress relief dilation after excavation. Whilst there is an extensive published database of in situ stress measurements comprising ‘hydrofrac’, ‘over-coring’ and ‘slotter’ stress measurements, these data indicate a considerable spread of results. The traditional approach to interpreting this data has been to attempt to fit linear correlations to stress versus depth data, based on personal experience and ‘back-analysis’ of monitoring data during construction. However, there are a number of such correlations in the literature and there is divergence of opinion regarding the assessment of ‘background’ in situ stress and appropriate upper and lower bound values for design. This paper provides a brief review of the published data; suggestions on an alternative ‘risk-based approach’ to assigning in situ stresses for design; and, proposals on how in situ stress tests may be conducted in future to improve the quality of the database available to designers.CITATION:Macklin, S, McKay, G and Erskine, M, 2014. A review of the in situ stress database for tunnel design in the Hawkesbury Sandstone, Sydney, New South Wales, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 171–178 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By M. J. Nicol, T. Moyo

Ammoniacal solutions are an effective lixiviant for the oxidative dissolution of some mineral sulphides. A detailed study of the anodic dissolution of chalcopyrite in ammonium sulphate-ammonium hydroxide solutions has been carried out using cyclic voltammetry, chrono-amperometry and rest potential measurements. The role of the copper(II)/copper(I) redox couple in the oxidation process has been evaluated. Rest potentials have been found not to be affected by oxygen but to increase with an increase in initial copper(II) concentration. Pseudo-steady-state anodic current densities measured in the absence of copper(II) ions at the rest potentials obtained in the presence of copper(II) ions increase with increasing concentration of copper(II) ions, confirming the positive effect of copper(II) ions on the rate of dissolution of the mineral. Cyclic voltametric and chrono-amperometric data show that in the absence of initial copper(II) ions, the rate of dissolution in the presence of dissolved oxygen is significantly lower. These results confirm that the effective oxidant for the mineral under the conditions of the study is copper(II) and not dissolved oxygen. Coulometric measurements have been used to establish the stoichiometry of the anodic reaction at different potentials.

Jan 1, 2014

By F W. Irwin

In recent years, a number of significant developments have occurred in the steel industry which are no-table and of general interest. This paper is confined to the steel-melting phase of the business. The development of high production rates on Stelco's Basic Open Hearth furnaces is chronologically summarized. Al-though various aspects of this subject have been presented previously, this paper summarizes the developments in high fuel rates, the usage of basic refractories, low and high oxygen rates and hearth maintenance. Background T HE interest which has been shown in steelmaking techniques in the past few years has been due, primarily, to the extremely high production rates obtained. Upon further study of the facilities and techniques employed to generate this steel at record rates, tonnage oxygen appears as the common factor. It can be stated that tonnage oxy-gen has revolutionized steelmaking techniques to a degree never before encountered. It was only about ten years ago that the use of large amounts of pure oxygen in a steelmaking

Jan 1, 1965

By James W. Derrick

General widespread interest in fine coal cleaning circuits did not occur in the United States until the mid 1960's. Up until this period the relatively low price for which bituminous coal was sold did not justify for many operators the capital and maintenance costs associated with the beneficiation and drying of fine coal. However, with current growing interest in this area, the introduction of new types of process equipment along with modifications to existing components is occuring to maximize the recovery of coal fines. In 1973 Derrick Manufacturing Corporation introduced high frequency screening machinery into the coal industry. The first design consisted of a 4 ft. wide 18 ft. long single deck screen frame with three 100 mesh woven wire screen surfaces divided by repulping troughs for the addition of wash water. In addition, a special slotted rubber dewatering deck was installed on the discharge end of the unit to assure adequate dewatering of the screen oversize. This panel had nominal 25 mesh X 3.0" slotted openings. The machine was also equipped with a special high speed-low amplitude (3600 RPM .032" % AMP.) integral vibrator.

Jan 1, 1983

By Luino Jr. Dell'osso, Richard L. Every

The enormity of the methane-in-coal problem is discussed, with a brief summary of the state-of-the-art. Laboratory techniques and data on the desorption of methane from Pittsburgh seam coal are presented and discussed and include the effect of time, temperature and vacuum. Under laboratory conditions, it was possible to displace 90 per cent of the residual methane by flooding the coal samples with carbon dioxide. Carbon dioxide was found to be three times more effective than air and almost five times more effective than helium.

Jan 1, 1972

By Lawrence Pelham

The demand or consumption of fluorspar has been somewhat taken for granted in recent years, except for the specific interest of those that produce, market, and/or consume the commodity. A tradition was established of thinking that as the steel and aluminum industry goes, so goes fluorspar. This is much less true today than in the past. The industry is becoming more dependent on chemical industries that feed primarily off hydrofluoric acid (HF) production. The Bureau of Mines recently published an assessment of world fluorspar reserves and resources that created a foundation of valuable data that can be used to monitor fluorspar availability. Celebrations were held this year commemorating the 100th anniversary of the isolation of fluorine. The United States and other countries continue to struggle with the controversy of ozone depletion and the effect of fluorocarbons on the atmosphere. The goals for the U.S. Government's strategic stockpile are being reevaluated. The market for fluorine chemicals is changing and diversifying, making it a challenge to assess and forecast fluorspar/fluorine demand. This paper reviews the recent past of fluorspar and helps set the stage for a more detailed assessment of this critical commodity.

Jan 1, 1986

By B. K. Cantrell, K. L. Rubow

"The US Bureau of Mines and the University of Minnesota have developed design and performance criteria for a personal diesel exhaust aerosol sampler for underground coal mines. These are based on the premise that size can be used to separate diesel exhaust aerosol, which is mostly submicron in size, from coal dust aerosol, which is mostly greater than a micron in size. The sampler has three stages: a respirable aerosol preclassifier, a 0.8-um aerodynamic diameter inertial impactor to collect mineral dust and a final filter to collect the diesel aerosol. Using a sample flow rate of 2 L/min and gravimetric analysis to within 0.1 mg, the measure sub-0.8 um diesel aerosol has an a-priori limit of detection of 0.3 mg/m3.A miner working in an underground coal mine with diesel equipment is exposed to a wide array of pollutants from the diesel exhaust. These include CO, CO2. NO, NO2, SO2, diesel exhaust aerosol, and a variety of hydrocarbon compounds. A quantitative definition of the health risk resulting from these exposures remains elusive. During the past several years, though, progress has been made in defining the problem.Results from epidemiological studies by Garshick et al. (1988 ), animal inhalation studies by Mauderly eta). (1986), Iwai et al. (1986), and Brightwell et al. (1986) and in vitro studies by Lewtas et al. (1986) have provided sufficient data for the National Institute of Occupational Safety and Health (NOSH) to recommend that ""whole diesel exhaust be regarded as a 'potential occupational carcinogen,' as defined in the Cancer Policy of the Occupational Safety and Health Administration"" (NIOSH, 1988). NIOSH further stated that ""though the excess risk of cancer in diesel-exhaust-exposed workers has not been quantitatively estimated, it is logical to assume that reduction in exposure to diesel exhaust in the workplace would reduce the excess risk.""The Mine Safety and Health Administration (MSHA) has also been directed by an advisory committee to establish a diesel exhaust aerosol standard and to establish regulations to minimize exposure to diesel pollutants in underground coal mines (MSHA,1988). Both reports point out the need for development of measurement techniques for respirable diesel aerosol.In the past four years, the US Bureau of Mines (Cantrell,1987 and Cantrell, et al. 1987), in cooperation with Marple, et al. (1986), at the University of Minnesota's Particle TechnologyLaboratory (PTL), have studied the use of size-selective sampling techniques to measure the mass concentration of diesel aerosol in underground coal mines. Results from these studies have been used to develop design and performance criteria for a personal diesel exhaust aerosol sampler for use in underground coal mines.These criteria are based on the premise that size-selectivesampling techniques,can be used to separate diesel exhaust aerosol, which is predominantly submicron in size, from coal dust aerosol, which is mostly greater than a micron in size. In addition to the performance criteria, this paper discusses the laboratory and field test data used to develop the criteria."

Mar 1, 1992

By T. Majcherczyk

Shaft lining reinforcing analysis of two shafts under construction has been presented in this study. The first shaft was driven from the surface, while the second was deepened. Mining and geological conditions have been studied with respect to the lining capacity. The improvement of shaft stability comprised two elements, i.e. reinforcement of the shaft lining capacity and improvement of the strength properties of the rock mass. In both tested cases, the particular hazard was connected with non uniform loadings of the lining, which could generate shearing stresses within lining structure. Thus such elements as armored concrete with high strength properties, bolting and injection sealing of the rock mass, and the use of special ring reinforcing the shaft lining have been used in order to reinforce the shaft-rock mass system. Practical conclusions related with new technological solutions, allowing the rock mass and shaft lining reinforcement, have been included for the present study. Practical conclusions related with new technological solutions, allowing for rock mass and shaft lining reinforcement, have been also included to the present study.

Aug 1, 2013

By T. H. Etsell, P. Kerr, Qi Liu

"The objective of this investigation was to study the reaction mechanisms during the reduction of iron oxides in the presence of calcium chloride and carbon black as a simplified iron segregation process. The gas phase was analyzed by mass spectroscopy and the solid reaction products were analyzed by scanning electron microscopy. Mass spectroscopy, combined with thermogravimetric analysis and differential scanning calorimetry, revealed the presence of several gases at elevated temperatures over time, and the scanning electron microscope in combination with energy dispersive X-ray analysis illustrated the growth of a metallic iron phase on or near the carbon substrate. The results correlated well with similar copper and nickel segregation processes, but also introduced new insights that challenge the simplicity of the current models. The formation and transport of gaseous iron species to the carbon substrate in the presence of steam and hydrogen were evident during the reduction process that was studied; however, there is more happening at a mineralogical level, based on evidence of a liquid phase resulting in substantial growth due to an apparent fluxing effect created by the calcium chloride.These results help to better explain the chemical reactions and, in turn, the thermodynamics and kinetics of iron segregation processes related to the beneficiation of low grade complex iron ores. The results are also applicable to the production of metallic iron and concentrated titanium dioxide from ilmenite ores. The benefit of this process is that it allows ores in which the iron minerals are intimately associated with gangue minerals to be processed in circumstances where conventional mineral processing techniques are unsuitable or incapable of upgrading the material."

Jan 1, 2016

The floatability of a bituminous coal in NaG solutions was evaluated using a modified Hallimond tube to delineate the role of the electrostatic interaction between bubbles and particles in determining the coal hydrophobicity. Zeta potential measurements showed that bubbles are negatively charged in the entire pH range tested, while coal particles are positively charged below pH 6.0 and negatively charged above it. Also, both sodium and chloride ions were confirmed to act as indifferent ions without any specific effects for both coal particles and bubbles. Flotation as a function of pH exhibited a maximum and minimum at low salt concentrations which is shown to be determined mainly by the coal hydrophobicity as measured by a new hydrophobic levitation technique. At high salt concentrations (above 0.1 mole/dm3), the flotation without such maximum or minimum is controlled by the electrostatic interaction between the bubble and the particle.

Jan 1, 1992

By Q. J. Liu

The flotation circuit and the reagents of the all-sliming flotation about low grade and hard operation on zinc oxide ore are researched in the paper. The results indicated that there are many types of zinc minerals in this ore, and the composition is very complex. They include hemimorphite, smithsonite, hydrozincite and so on. The ore is seriously sliming. In light of the ore properties, three kinds of flowsheets have tested. They are gravity concentration (cleaning tables), flotation, combined process of gravity concentration and flotation. The test showed that the recovery of zinc is only 17.08% in the gravity separation. In combined process of gravity separation and flotation, the recovery of zinc concentrate is close to 70%. But the flow-sheet is complex and hard to control in the production. The floatation circuit is feasible. In the test, it pay attention to investigate the new combined reagent which is used in selective all?sliming flotation process. The effects of slime are eliminated by the multi-loop treatment of middling. In flotation, the final recovery of concentrate is 88.76%; the grade is 29.50%. The recovery of physical ore is 93%; and the recovery of -10mm fraction is more than 65%.

Jan 1, 2014

By N. Shi, T. G. Joseph

ABSTRACT: An interactive cable shovel simulation has been developed to mimic any shovel dipper geometry for a given cable shovel operating in any homogeneous face material. This interactive cable allows the user to predict shovel performance in any face material encountered and track both its ground stability and the dipper-ground interaction. An embedded Microsoft® Visual Basic spreadsheet was used as the platform for developing an interactive simulation that allows for maximum user-defined parameter input and interactive visual output. The result is an analytical dipper-ground interaction solution that yields crowd, hoist, and digging effort as a function of face activity position.

Jan 1, 2011

By R. D. Lrwin, W. M. Mullins, S. Venugopa, J. C. Malas

"Physical models for acoustic emission (AE) are introduced and expressions are derived to predict AE activity from such parameters as applied stress, strain and strain-rate. These models are then incorporated into a visco-plastic finite-element simulation program, and the acoustic emission event rate generated during metal forming operations are predicted. Simulation results are presented for upsetting operations on a typical C-Mn type steel for various friction and die geometry conditions. The AE model predictions compare well with the limited available experimental results reported in the literature and demonstrate that AE signatures can be reliably simulated. The signatures predicted for metal forging are fairly insensitive to processing parameter changes. This suggests that AE event rate monitoring may not be well suited to process monitoring for forging. However, the size of the features is conjectured to influence the frequency content of the AE signals. Thus, since current simulations include only the ability to predict the number of events for a set of processing conditions, future work is required to simulate the duration and magnitude of acoustic events. Fourier analysis techniques may then be applied to investigate correlation with microstructural features.IntroductionThe open loop control system method for deformation processing design, as described by Malas et al. [1 ], consists of several steps in series to achieve the final design. The first step uses microstructure development models to determine the optimum deformation path to achieve the desired final microstructure. The second step, the process model, calculates the processing parameters required to achieve this deformation path. Finally, the metal-working system uses the required processing parameters to produce the part. Figure 1 shows this in block diagram form"

Jan 1, 1997

"Depletion of known ore reserves and increased demand for precious metals have caused a revolution in biohydrometallurgical processing technology for gold recovery. Known ore deposits and future discoveries are most likely to be lower grade sulfide ores that can be difficult to recover with current leaching technology. Future metal recovery operations will increasingly use bio-oxidation techniques.Bacteria are an integral part of mineral cycling and mineral transformation in nature. Although biological processes are recognized as part of the mineralization and oxidation reactions in some ore deposits, they have only recently been applied to enhancing metal recovery in hydrometallurgical procedures. This paper explores the traditional metallurgical application of biological leaching and oxidation reactions and reviews the complete range of bacteria available for metal recovery systems. Pre-treatment of ores with bacteria improves metal recoveries in tank leaching systems and shows promise for heap leaching methods.IntroductionThere is no longer any question that bacteria playa natural role in the on-going transformation of some ore deposits (1,2). As applied to sulfide ores, a few strains have been specifically identified that exhibit a natural leaching potential (3). These bacteria can be isolated from waters and soils in old mining districts where they contribute to continuing leaching and pollution problems in acid drainage and heavy metal solubilization. Sulfur and iron bacteria as well as many heterotrophic strains have also been found in ore deposits and sedimentary rocks at depths up to 2000 meters (4). Their presence in both ore deposits and processed ores shows the microbial association with natural leaching and the potential role that bacteria can play in the development of new leaching technology."

Jan 1, 1988

By M. D. Monroe

Getting the best match between truck and haul road requires examination of many factors and their effect on the bottom line. Most mines use a bottom line measure based in some way on cost per ton of material moved. This measure focuses on the two components of truck haulage cost per ton: productivity (or performance) and operating cost. Productivity can be measured or predicted for specific tasks using either field measurement or modelling. Individual tasks can be combined to provide a larger scale, longer term net figure for total mine output. True cost is more difficult to capture as they are time and task oriented and can be influenced by a summation of factors over a truck lifetime. For example, "allocated" costs, such as owning (depreciation) and some repair costs, are spread over long periods of time. Other cost, such as fuel and tires can be tied more directly to certain tasks such as fuel and tire cost. This paper focuses on the more direct, task-oriented factors that affect truck productivity and cost.

Jan 1, 1992

By A K. Raina, V M. S R Murthy

Rock mass response in blasting is an important element to determine the performance of a blast along with its other outcomes. The near-field monitoring for rock mass response analysis is vital for determining the behaviour of a blast; however, due to costly and cumbersome methods involved in such measurements the subject has received scant attention so far and the publications on this account are perfunctory in nature. This paper presents a non-destructive method to monitor the blast-induced pressure in the rock mass at a distance from a blasthole. The methodology of monitoring and a few examples of actual field monitoring are detailed in this paper. The responses of the rock in the near-field of a blasthole under dynamic loading have been documented to predict fragmentation and throw. The proposed method has also been used in limited cases earlier by the author to predict flyrock using a semi-empirical method and trajectory equation. The pros and cons of the method are discussed while throwing light on the actual response and the prediction of fragmentation and throw of blasted rock.CITATION:Raina, A K and Murthy, V M S R, 2015. Measurement of blast-induced pressure in bench blasting and deciphering explosive performance through rock mass response analysis – a methodology, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 501–508 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By Martin H. Stanczyk

The Organic Act of 1910 established the Bureau of Mines and gave it authority and responsibility for conducting research on separation, recovery, and recycling of waste products and scrap generated by the mineral and metals industries and the consuming public.(1)1 It was apparent to our Nation's leaders even then that mineral resources, once mined, are irreplaceable and that the development of methods for recycling the values contained in wastes would be required to solve the problem of even¬tual scarcity, Estimates of the increase in per capita consumption of mineral resources in this country indicate that the consumption of metals, minerals, and fossil fuels by 1980 will be double that consumed in 1970 (2). The United States can expect to meet its future mineral needs in three basic ways: the first is through increased production of primary raw minerals; second by increasing imports from foreign sources; and third by recycling secondary materials and metals that were formerly discarded as waste. Rather than consider these

Jan 1, 1972

By F. Hashiuchi

In 1996, the Saganoseki custom smelter & refinery successfully shifted to a single flash smelting furnace operation and increased the copper production capacity to 450,000mtpy in 1998. As the next step, Saganoseki planned to further increase the productivity, especially in the area of P.S. converters and acid plant. As the results of modifications and operational improvements, the gas washing & cooling sections of the Saganoseki acid plant were consolidated from 3 to 2 lines, and increased the gas treatment capacity. The S02 converters in the acid plant were also modified to increase the acid production. By increasing the matte grade from 65 to 68%, six PS converters have been successfully integrated into four, while maintaining the production capacity and reducing the environmental burden in 2005. This paper discusses recent operational conditions and the results of implementation of technological improvements.

Jan 1, 2007

By John S. Dunning

This paper is one of a series describing methods and costs of recovering sand and gravel from deposits in the United States and deals directly with the operations of the Atlas Sand, Gravel and Stone Co. at Farmington, Conn. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent local expenditures only and not total production costs. It is recognized that publication of total costs might in some instances cause embarasement to individual producers, as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations may ensue.

Jan 1, 1933