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By A. S. Bayne

WITH the great increase in the use of power-driven machinery in industry, and consequent large-scale operations, the hazards to which , workmen are exposed have become much more numerous than at the beginning of the century. This is especially noticeable in mining. In the past thirty years or so, improvements in methods of excavation and metallurgy have made possible the exploitation of deposits which would have failed to make ore in previous years. This improvement, together with the in-creased use of machinery, has facilitated the mining of tremendously greater tonnages with a marked decrease in unit cost of production. This 'speed up' in mining creates numerous problems demanding close attention of operators and necessitates careful prep;tratory planning, as well as diligent supervision of actual operations. Underground openings increase in size so fast, and all phases of mining, mucking, and transportation proceed at such a rate, that a short period of reduced vigilance on the part of operators . results in disaster, both from the standpoint of safety and economies. Happily, the challenge of increased hazards has been successfully met by a general application of the slogan 'Safety First'. Today, we have large manufacturing concerns devoted entirely to the development and production of safety equipment for the protection of workmen in various branches of industry. Machinery manufacturers, in co-operation with their mining customers, have included the best possible in foolproof devices in the manufacture of hoists, compressors, boilers, electric motors, and equipment of all kinds. Mining companies and private individuals spend thousands of dollars and devote a great deal of time to research with the single object of preventing accidents and combating miners? diseases. Governments throughout the world have written regulations into their statures for the protection of miners and operators. Staffs are appointed to enforce these laws and investigate accidents to ascertain means of preventing them for the future benefit of the industry.

Jan 1, 1938

By Matthew D. Meyer

SMART, an association of surface mining companies formed in 1995 to develop a coordinated approach to technology development for the mining industry, has recognized the need for the establishment of a worldwide database that continuously collects mining equipment data and provides metrics related to productivity and cost. Under the auspices of SMART, Syncrude Canada, Suncor Energy and Albian Sands Energy (three oil sands mining operations located in northern Alberta) have established a pilot project for mine benchmarking. This presentation will include a review of the pilot progress including: ???Data gathering techniques: means of collection and storage, proposed practice for data control and normalization, access to data/reports and format for data. ???Reports/analyses for individuals, across groups, within the total industry pool and publicly. ???Security and confidentiality of information belonging to identified parties. ???Sharing of best practices among members. SMART has identified two key deliverables to ensure success of the project. First, data supplied from surface mines must be validated and normalized to common definitions and then analyzed to provide participating companies with regular reports that allow them to understand their position and resultant opportunities to achieve world-class performance. This model maintains granularity of the data for each operation that can then be recombined into standard comparisons or specific indices as required. The general categories of: operating delays, maintenance downtime, standby, and scheduled downtime, have been used to frame comparisons. Second, participating companies are looking to go behind the indices to identify and share best practices that distinguish particular operations. The spirit of cooperation between the companies involved in the pilot project is meant to be a model for future expansion of the benchmarking project.

Apr 1, 2005

By Neil Camarta

$6 Billion Dollar Education ?? Construction is like war ? you need a command and control organization ?? A strong Owner?s team is a must ?? Smaller is better ? break the project into bite size chunks ?? New technology is risky ? lots of construction and start-up risk ?? Safety can be successfully managed ?? Don?t expect contractors to ?work well together? ?? Never, ever let Mining Engineers run stuff than can catch fire

May 1, 2008

By E. M. De Souza, J. F. Archibald

This paper examines aspects of Canadian mine backfilling operations that may be implemented to assist in reducing solid waste production, lowering energy costs, and restricting Greenhouse Gas emissions. Many Canadian underground mines use backfill to mitigate environmental effects associated with tailings disposal. Backfill production and disposal are energy intensive processes that require an average energy cost of 37.7 MJ/tonne of backfill to complete. Mine backfills, in engineering applications, also commonly make use of cement as a stabilizing agent. Cement requires an additional energy cost ranging between 4,637 and 6,600 MJ/tonne to produce. The large energy needs associated with mine backfilling and cement production operations create significant CO2 and Greenhouse Gas emissions. Approximately 1 tonne of CO2 and Greenhouse Gas is emitted for each tonne of Normal Portland Cement produced. For single mines producing 3,000 tonnes of backfill per day, considering both backfill and cement emission source terms, total emissions of CO2 ranging between 120.36 tonnes and 169.44 tonnes/day are anticipated. In Ontario, mining operations contribute 700,000 - 840,000 tonnes/year of CO2 and Greenhouse Gas emissions to satisfy backfill cement consumption needs alone. Potential reductions of cement in backfill would significantly reduce emission of these gases and lower their adverse environmental impacts. This paper identifies alternate, equally effective and lower cost binder agent strategies for cement in backfill that may lead to cement consumption reductions. Post-consumer glass represents one such potential alternative backfill binder. Over 950,000 tonnes of glass are disposed of annually in Canada, two-thirds of which exists in the form of easily recoverable glass packaging that is not currently recycled or reused. The partial replacement of cement by waste glass may address goals for reducing non-recyclable glass waste disposal; enhancing mine back filling operations; reducing total backfill energy costs; and ultimately reducing Greenhouse Gas emissions levels currently generated by the Canadian mining industry.

Jan 1, 2004

By L. Kilburn

"A survey of 281 mineral exploration agreements examines the ratios among three ways that may be used to purchase an interest in a mineral property, viz: pay cash, pay shares and make future expenditures on the property.The dollar value of the future expenditures exceeds that of cash or shares by about nine times in most of the 110 agreements that contain cash-expenditure or share-expenditure components. Results suggest that cash and shares are treated about the same in terms of value.Buyers and sellers have opposing priorities for the way that they prefer to purchase a mineral property. These opposing priorities should give rise to a perceived 50:50 balance between cash/share payment and future expenditures to satisfy the idealized situation described by most definitions of fair market value (FMV). This balance between cash/share payments and future expenditures appears to be rationalized in negotiations to a FMV when expenditures are nine times greater than cash and/or payments.On this basis, it is proposed that the FMV of a property may be determined by aggregating the dollar amount of the cash/share payments plus one-ninth the dollar value of future expenditures, as set forth in the respective purchase agreement, and proportionately applying such aggregate to full property value."

Jan 1, 2005

By John Plecash

This paper comprises a general outline of all of the developments, including the history, geology, mining, milling, power and transportation installations, at the gold mining operation of La Luz Mines Limited and the copper mining operation of its wholly-owned subsidiary, Rosita Mines Limited, both located in north-central Nicaragua. The low-grade, gold-bearing ore-bodies of La Luz Mines, contained in highly fractured and folded Lower Cretaceous sedimentary rocks, were from 1909 to 1928, mined and treated by primitive methods by the La Luz and Los Angeles Mining Company. The abandoned property was acquired by La Luz Mines Limited in 1936, and was equipped with modern machinery and put into production in 1939. Between 1939 and 1948, the daily rate of production was in-creased from 300 tons per day to 2,-000 ton per day. The ore reserves available for open-pit mining were depleted in 1954. Since then, the entire production has come from under-ground operations.

Jan 1, 1963

By Dalton. J. L., H. P. Dibbs

An account is given of investigations into the application of two neutron methods to the on-line analysis of slurries. One deals with the application of the neutron moisture gauge principle to the determination of the water content of iron oxide slurries, and the other with the application of gamma radiation from thermal-neutron-capture to the determination of the composition of aqueous slurries of iron oxide, copper oxide, zinc oxide and sulphur. Linear relationships were found between the composition of the slurry and the neutron count-rate in the first study, and between the slurry composition and the prompt-gamma-ray count-rate in the second study. A mathematical relationship has also been developed which relates changes in the prompt-gamma-ray counts from hydrogen to changes in slurry composition.

Jan 1, 1973

Once applied, EarthZyme reduces the tendency for a road to exhibit common maintenance issues: wash-boarding, rutting, heaving, potholing and dust.

Aug 1, 2013

By Donald E. Archibald, Gerald A. Allcott

"Noranda's Heath Steele Mine is located 35 miles north of Newcastle in northern New Brunswick. Blasthole open stoping with partial delayed filling is the major mining method in use. The selection of stope and pillar dimensions to ensure mine stability was originally subjective. This paper describes the progress made in attempting to rationalize design.One major feature is the fracture pattern. The main orebody now being mined, the B zone, has undergone five periods of folding and each period of folding developed a family of fracture planes which are axial planar to that particular fold pattern.The other major features considered are the calculated increase in stress due to mining and depth and its relationship to measured strain. Experience has shown that ground problems affecting production have usually originated in rib pillars. Field observations of ground deterioration and multi-wire extensometer measurements of strain are tabulated together chronologically for each pillar.A factor representing stress and a common plane of weakness are identified. Graphical analysis is used to determine the effect of the plane of weakness on a typical stress/strain curve and provides a base for the design of pillars."

Jan 1, 1981

By H. Golzarpoor

Life Cycle Analysis (LCA) is a methodology for evaluating the environmental impacts associated with a product during its life cycle. LCA is identified as the most reliable method for verifying environmental impacts; however, current LCA-based approaches have certain limitations for environmental analysis of construction products. Integration of the LCA methodology with Discrete Event Simulation (DES) provides a sound framework for modeling and analysing the environmental impacts of construction products. LCA and DES is one possible combination for analysing the cause and effect of various scenarios where time, resources, and randomness of input variables affect the outcome and, therefore, has the potential to address the shortcomings of LCA in construction. Recent studies in disciplines other than construction such as manufacturing systems have revealed positive effects on evaluation of environmental metrics while integrating LCA with DES; however, this integration has not yet been applied for environmental analysis of construction products. By implementing LCA data in a DES model, this research proposes an environmental model of earthmoving operations in a case study. Environmental variables are simultaneously assessed with production variables in the same simulation model and the integration of DES and LCA is discussed.

Aug 1, 2013

By M. B. Myers

The subject matter of this paper will be discussed under three main headings. 1.-Fire-Resistant Fluids: (a) the need for such materials, based on historical events; (b) a definition of fire -resistant fluids; (c) general description, characteristics, operational parameters, advantages and disadvantages of oil-in-water emulsions (HFB), water-polymer fluids (HFC) and anhydrous or synthetic fluids (HFD). 2.-A review of equipment associated with the use of fire-resistant hydraulic fluids; (a) performance testing of hydraulic equipment, i.e. gear pumps, vane pumps, axial and radial piston pumps, hydraulic motors, etc., pressure, speed, filtration limitations, etc., and effects on valves, elastomers, paints, etc.; (b) hydraulic system design features and selection of suitable units; (c) types of mining applications currently employing fire-resistant fluids. 3.-Test methods used to evaluate fire-resistant fluids: (a) fire testing methods, i.e. wick tests, spray ignition testing, hot manifold tests, factory mutual tests, all to establish fire-resistancy parameters and acceptance; (b) new developments in fire-resistancy evaluation; (c) the examination of other performance tests, e.g., effects of evaporation, sliding wear, life of rolling element bearings, etc.

Jan 1, 1979

By C. Butcher

Numerical simulations of straight tube hydroforming of a dual phase steel were performed using both upper and lower bound constitutive models for porous ductile materials. The Gurson model is based upon an upper bound approximation to the material behavior and thus overestimates formability. Conversely, a lower bound solution to Gurson's unit cell geometry was developed by Sun and Wang to provide a conservative estimate of formability. The effect of a compressive axial load (end-feed) on damage development and tube formability is investigated. The resulting upper and lower bound models successfully captured the experimentally determined burst pressure, formability and failure location.

Jan 1, 2010

By S. K. Shaha, W. Kasprzak, D. L. Chen, J. Friedman, F. Czerwinski

The role of solutionizing conditions within the T6 heat treatment of the cast Al-Si-Cu-Mg alloy with micro-additions of Zr-Ti-V was assessed in terms of their influence on microstructure and mechanical properties. As a solution treatment, a single step process at 485 and 510oC and a two-step process at 510 and 525oC for varying time intervals from 0.5 to 9 h, were examined. In all cases, solution treatment was followed by isothermal aging at 150oC for 100 h. The microstructural analysis showed that the solution treatment changed the eutectic silicon morphology from needle-like, present after casting, to spherical shape in the T6 state and that the extent of changes was strongly influenced by temperature and time. The Cu- and Mg-rich phases completely dissolved during solution treatment while the Fe-containing phase, Al8Si6Mg3Fe, remained partially in the microstructure. The Ti, V and Zr containing phases, Al13Si2Ti3Zr and Al3Si26FeTiV10, present in as-cast state, were partially dissolved during solution treatment, reducing their size by 10 - 48%. The studied alloy reached the maximum ultimate tensile strength of 335 MPa and yield stress of 303 MPa for two-step solutionizing with a total time of 4.5 h. It is concluded that the two-step solution treatment resulted in higher tensile properties than the single-step process.

Jan 1, 2015

By M. Tsesarsky, M. Hazan, E. Gal

"Rock masses comprised of stiff inclusions in softer matrix are common in various geological environments. The heterogeneity and multi-scale nature of these materials make the evaluation of their mechanical properties a challenging task, which cannot be accomplished using conventional laboratory tests and composite mixture rules. We employ the homogenization method to estimate the mechanical properties of geological materials with inclusions. The homogenization method solves the equations of elasticity on the material (microscopic) scale for a unit cell subjected to unit strains under periodic boundary condition. The micro-scale elasticity equations are solved using the Finite Elements Method, and are in turn used to obtain the structure scale (macroscopic) material matrix.In this research, Finite Element models for unit cells with spherical and ellipsoidal inclusions were developed. Using the unit cells, a parametric study of the geometrical and statistical microscopic properties of the material composites was performed. The following parameters were studied: volumetric ratio, Young’s modulus ratio, size-distribution of inclusion and inclination angle of inclusions. The main purpose of the parametric study was to study the deviation from isotropy as a function of the aforementioned parameters.It was found that for volumetric ratio of 5%-40%, the deviation from isotropy increases, as the volumetric ratio of inclusions increases. For spherical inclusions, most of the cases studied exhibit quasiisotropic behaviour; whereas ellipsoidal inclusions exhibit considerable deviation from isotropy. The inclination of the ellipsoidal inclusions enlarges the deviation from isotropy (9% at random orientation and 26% at 0°)."

Jan 1, 2015

By F. P. Morawski, J. E. Schelske, J. R. Geddes, B. R. Eberts, D. M. Wilson, J. D. Jeffries

"The Griffith Mine is located 200 miles northeast of Winnipeg and is 30 miles south of Red Lake, Ontario. Owned by The Steel Company of Canada Limited and managed by Pickands Mather & Co., it has an annual rated capacity of 1.5 million tons of high-grade iron ore pellets with an analysis of 66.3 per cent iron and 4.5 per cent silica.Development of the mine and construction of the plant got underway in January of 1966 and operations began in February of 1968. The orebodies outcrop on the shore of Bruce lake and run under the lake. The ore in its crude form is a metasedimentary low-grade magnetite and occurs in a highly folded banded formation. The average iron analysis of the crude is 29 per cent and the over-all weight recovery is 32 per cent.In order to mine the portion of the orebody under the lake, the soft varved clay on the lake bottom was hydraulically dredged and a dyke constructed of rock, with till used to provide an impervious seal on the lake side of the dyke, prior to dewatering.Mining is carried out by conventional open-pit tech-niques. Ore dressing is achieved by combining one crushing stage and a two-stage grinding system, with beneficiation by magnetic separation, hydroseparation and flotation. Agglomerating is done with conventional balling drums and pelletizing is carried out in shaft furnaces.Of interest and discussed in detail are the 32-foot autogenous cascade mills ."

Jan 1, 1970

By L. W. Vollmer

Introduction During the past three years at least fifty strings of 9% nickel steel tubing have exhibited excellent resistance .to the variably severe corrosive conditions typical of many of the sweet condensate wells in Mississippi, Louisiana, and Texas. This experience, and the characteristically outstanding performance of other ?nickel alloy steels under hydrogen sulphide corrosive conditions, dictated the selection of 9% nickel steel tubing for the second well drilled in the sour condensate Pincher Creek field of southwestern Alberta. The damaging effects of the Pincher Creek reservoir fluids on well equipment had been manifested in the discovery well by the rapid and not yet fully understood failure of API Grade N-80 tubing, stainless steel wire lines, and alloy steel fishing tools. Two very unexpected failures in the 9% nickel steel tubing, after only six days of service in production tests, instigated an extensive and continuing investigation to ascertain the probable cause of failure. This discussion presents some of the results obtained thus far which cast a little light on the perplexing behaviour of steels in hydrogen sulphide environments in general, and in sour condensate wells in particular. History of Tubing Failures Walter Marr well No. 1, in which the 9% nickel steel tubing failures occurred, produces from the Madison lime at the depth interval approximately 12,200 to 12,750 feet. The gas-oil ratio is about 26,000 and the gas contains 10.2 per cent hydrogen sulphide and 6.3 per cent carbon dioxide by volume.

Jan 1, 1952

The topic of the relationships between energy and particle size has had two very active periods -the first in the early thirties, when the relative merits of Rittinger's and Kick's proposals were vigorously debated; the second in the early fifties, when Bond's Third Theory was published. This second stage has produced several contributions that have provided a clearer picture of energy /size correlations in comminution. Derivations of a general relationship have been made from single-fracture experiments and from the rate of comminution, and both methods arrive at an equation of the type E = AK-11? The constant A in the equation may be regarded as a grindability parameter. In some respects, an understanding of the phenomena associated with comminution is still lacking, and research in this field should therefore be expanded. T HE SEARCH for a relationship between the energy consumed in comminution and the size of the broken product has been long and varied, and many

Jan 1, 1964

By V. A. Ettel

Current practices in electrolytic winning and refining of copper , nickel and zinc are reviewed from the point of view of their respective energy requirements. The electrical energy requirements of these processes are broken down in to the individual components, which belong to two basic categories: (a) thermodynamic energy requirements (G of the desired reaction) : (b) energy losses (anode and cathode polarizations, ohmic drops in the electrolyte and in the cell hardware, energy losses due to unwanted side reactions and electrical shorts). The individual energy components are separately examined for each electrolytic process and the potential for energy saving in these processes is discussed. It is shown that many potential energy-saving measures are uneconomical at the present time, as they increase over-all operating costs. The discussion is focused on those approaches which hold most promise for the future.

Jan 1, 1977

By G. Armand, G. Arnold, A. Giraud, C. Auvray

The knowledge and understanding of the mechanical behavior of claystone is of critical importance in the aim of nuclear wastes storage. In this study, specimens of Callovo-Oxfordian claystone (COx) have been obtained from the ANDRA underground research laboratory in Meuse/Haute-Marne (France). This claystone is composed of carbonate inclusions (10-50µm) embedded in an argillaceous matrix (representing expanding clay minerals, such as smectites). The matrix itself is also multiphase and composed of clay aggregates of 1µm-size carbonate and quartz inclusions. This multiphase microstructure leads to a high heterogeneity witch was analysed through nanoindentation test grids. Moreover, the mechanical behavior of the claystone matrix is highly sensitive to humidity and temperature. The nanoindentation tests were performed in a climatic (i.e. temperature and humidity controlled) chamber at relative humidity levels from 50% to 98% and at two temperatures: 20°C and 60°C. In a first step, the curves of indentation were analysed using the commonly used Oliver and Pharr’s approach. Other wellknown parameters as the creep factor were also extracted. In a second step, Fisher-Cripps model (Fischer- Cripps, 2004) and Vandamme and Ulm model (Vandamme & Ulm, 2006) were used to identify viscoelastic properties. A statistical analysis is used in order to extract mechanical characteristics of the different phases. Hardness and elastic modulus decrease drastically with saturation (above 80% humidity) and to a lesser extend with temperature.

Jan 1, 2015

By E. Lee Cameron

Summary Records of the past show that the first mineral production in what is now the Province of Manitoba consisted of salt, obtained about the year 1800 by the evaporation of brine. Also at an early time in our history, the Ordovician limestone at St. Andrews Locks, East Selkirk, and other localities was quarried for use as building scone in the construction of forts and fur trading posts. Both salt and building stone are still produced in Manitoba, although not from the original sources. In addition, there is now a substantial production of a variety of other industrial minerals and their products such as lime, crushed stone, gypsum, peat moss, and bentonite. The annual dollar value of production of the industrial mineral industry in Manitoba is today greater than at any time in our past and is derived from a greater variety of products. At the present time, exclusive of the various gravel pits operated by the Provincial Department of Public Works, twenty companies operating thirty-four separate pits, quarries, or mines are producing industrial mineral raw materials in Manitoba. This paper attempts to outline the development of the industry from its start about 1800 to the present, giving general information on the various materials produced. Some suggestions regarding the possibilities of establishing new industries based on other raw materials are given at the end of the paper.

Jan 1, 1949