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A series of field and laboratory evaluations were conducted in order to characterize the effects of a Mann+Hummel SMF-AR® diesel particulate filter (DPF) system on the aerosols and criteria gases emitted by diesel engines. This system, with a durable sintered metal filter media and available active regeneration via an on-board electrical heater, has been considered for retrofitting diesel engines used in light- and medium-duty underground mining applications. Two DPF systems were installed on a forklift and locomotive from the underground mining fleet of the Vale?s Creighton Mine and evaluated over a 1,500-hour trial. This evaluation was complemented with field and laboratory emissions tests. The field tests were performed on the vehicles while at the Creighton Mine surface shop. During those tests, the emissions were assessed for the engines operated at hydraulic stall, high idle, and low idle conditions. The laboratory tests were executed at the diesel engine emissions laboratory at the National Institute for Occupational Safety and Health (NIOSH), here the DPF removed from the forklift was further evaluated at four steady-state engine operating conditions as well as at transient conditions using a custom-designed duty cycle. Very similar methodologies were used during field and laboratory tests to measure concentrations of aerosols and criteria gases in the diesel exhaust, both upstream and downstream of the DPF system. The concentrations and size distributions of aerosols were measured using a fast mobility particle sizer spectrometer, in exhaust diluted by a partial flow dilution system. The concentrations of CO2, CO, NO, and NO2 were measured in the raw exhaust using a Fourier transform infra-red spectrometer. Both field and laboratory emissions tests showed that the evaluated DPF systems were very effective in reducing aerosol emissions from all tested engines, and for all test conditions. The systems were found to have minor effects on gaseous emissions from those engines. The findings from this study should help the mining industry to better understand the benefits and challenges of using DPF systems to control the exposure of underground miners to diesel aerosols.

Aug 1, 2013

By E. C. Sanford

A laboratory-scale batch extraction unit and operating procedure for studying the hot-water separation of bitumen from Athabasca tar sands are described. The extractor evolved from earlier units and has been in use by Syncrude Research for the past 10 years. By using a unit such as this, it is possible to study tar sand feed quality and the effects of chemicals on the hot-water extraction process, while process variables are held constant. Data are presented to demonstrate the importance of surfactants to the process and the interrelated role of inorganic bases and surfactants.

Jan 1, 1979

By David Stone

The Beal Mountain Mine near Anaconda, MT is an interesting case history of a mine that has continued operations despite several large pit wall failures over a period of about 10 years. The largest event involved some 3.9 million tons of rock that has moved steadily at a rate of about 0.05 ft/day since 1992. This paper documents the geotechnical instrumentation and monitoring programs implemented at Beal to provide the company with a comfortable baseline that supported ongoing operations. The success and failure of a variety of stabilization measures will be discussed, along with typical instrumentation responses for several significant events. The success of Beal Mountain serves as a good model for mines faced with serious geotechnical challenges.

May 1, 2001

By W. A. Jones

"The Ross mine, a subsidiary operation of Hollinger Consolidated Gold Mines, Limited, is near the north end of lot 1, con. II, Hislop tp., Ontario. The property comprises the north half of lot 1, con. II, and the south onethird of lot 1, con. III. It is readily reached by a good motor road from the village of Ramore, 7 1/2 miles to the southeast on the Ontario Northland railway. The mine is being developed to a depth of 1,500 feet, and the current daily production rate is approximately 300 tons. From the inception of operations in March 1935 until December 31, 1945, 692,000 tons of ore, with a total value of $5,762,685, was milled . The silver to gold ratio of 1.48 to 1 is unusually high for Ontario gold mines.TYPE OF 0REBODIES AND MINERALIZATIONThe orebodies consist of lens-shaped and pipe-like stringer lodes and tabular vein zones composed of parallel quartz stringers. The host rocks are steeply inclined eruptive breccias and tuffs, striking N.70°W., intruded by very small stocks of red syenite. The orebodies appear to be spatially related to an intricate system of fault planes. Hydrothermal alteration is widespread and is not zonally related to individual quartz stringers. The wall-rocks contain abundant fine-grained pyrite, but gold is confined to the quartz stringers.RELATIONSHIP TO REGIONAL STRUCTURELack of outcrops has prevented the detailed mapping of the Keewatin complex in the vicinity of the Ross mine with the degree of success that has been achieved in the Porcupine area.A northwesterly trending belt of slates and greywackes, bounded by faults, forms the central part of a broad anticlinal arch about 3 1/2 miles north of the Ross shaft. Lava flows forming the south flank of the structure face south toward the mine. If the sediments are to be tentatively correlated with the large areas of Keewatin slates and greywackes of the Porcupine area, it must be assumed that they are younger than the lava flows and that they have been down-faulted."

Jan 1, 1954

By Robert D. Brown

"All ten Canadian provinces have now tabled their 1981 /82 budgets . Only the provinces of Ontario, Quebec and British Columbia made more than minor modifications to their tax structures, with both Ontario and Quebec imposing major tax increases. In the past year, the federal budget was also released in the spring. Not so this year: we have that to look forward to in the fall!This month, Tax Notes presents a brief summary of the more significant tax changes introduced at the provinciallevels in the last months.Summary of provincial tax rate changesThe tax changes in this year's provincial budgets were both up and down- but there were far more tax increases than tax cuts.At the corporate tax level, two provinces, New Brunswick and British Columbia, increased their general corporate income tax rate; the former by two percentage points and the latter by one percentage point. Quebec, rather unexpectedly, sharply cut its corporate tax rate on business income, but increased some of its other business taxes at the same time. British Columbia reduced its corporate tax rate on small business income by two percentage points and Saskatchewan by one percentage point."

Jan 1, 1981

By Takanori Kokubo, Kenta Suzuki, Tomohiro Sasaki, Toshiya Anami

"Previous work has shown that the strengthening Al-Mn alloys with copper leads to the formation of an undesirable reduction in recrystallized grain size. In this study the mechanisms of strengthening and recrystallization behavior in a continuously cast automotive heat exchanger fin stockof Al-1.1wt%Mn-0.5wt%Fe-0.3wt%Si with a0.3wt%Cu addition were investigated. Metallurgical analysis revealed that the Cu strengthening was dominated by the formation of dispersoid particles, while solid solution strengthening decreased with the Cu additions. This result is attributed to the decrease in the amount of Mn solid solution. The post brazing recrystallized grain size was reduced compared to that not containing Cu. It is postulated that the Cu addition leads to a decrease in the amount of Mn in solid solution which leads to a finer grain size. This effect is attributed to Mn in the aluminum matrix inhibiting boundary migration but allowing other grains to grow during heat treatment. The results are rationalized based on particle stimulated nucleation (PSN), wherein dispersoid particles are more likely to become active recrystallization nuclei during the heat treatment. The increase in the number of active dispersoid particles with Cu addition is correlated to the recrystallized grain structure.INTRODUCTIONImprovements in properties such as strength, braze ability and corrosion resistance in thermal fin stock alloys are all means to gain improved efficiency in heat exchangers particularly in automotive applications. While Al-Mn alloys dominate automotive heat exchanger fin stock alloy, even small chemical compositional changes can profoundly influence these properties (Kawaharaet al., 2004; Yoshino et al., 2009). The microstructure (particularly the grain size and shape) also plays a key role in determining the product performance and hence the thermo-mechanical processing (TMP) must also be considered. The casting method (typically conventional direct chill, DC, or continuous casting) significantly influences the properties in no small part due to the very different TMP routes that are used. Continuous casting is generally favored for fin stock applications as its higher cooling rate (which can be 2 to 3 orders of magnitude higher than DC casting) leads to finer as-solidified intermetallic particles and an increase in super-saturated solid solution elements (such as Mn)that are known to improve fin stock performance such as strength, braze ability(Okiet al., 2008)."

Jan 1, 2018

By M. J. King, D. A. Van den berg, R. Fukuzawa

"Mercury bearing ore bodies are often treated for the production of copper, lead, zinc, gold, and silver. The mercury deports either to tailings or is collected during various stages of the extraction process. This paper reviews the relationship between various mercury collection processes and the subsequent management of the mercury by-product or waste. It focuses on mercury removal sequestration including cementation, sulphide precipitation, bulk neutralization, and carbon adsorption. Long term mercury management strategies including third-party stabilization, stabilized mercury co-disposal, secure storage, and mercury recycle are also evaluated. INTRODUCTIONMercury is produced in North America as a by-product of non-ferrous metals processing and from recycling of products such as dental amalgam, fluorescent lamps, and thermometers. Its toxicity is recognized to have significant negative impacts on the environment and human health. As a result, many countries are adopting regulations limiting mercury use and its uncontrolled release.The European Union banned mercury exports in 2011 and the United States will do so in 2013. The export bans aim to prevent mercury use in developing countries for activities such as artisanal small scale gold mining. However, by-product mercury production from the non-ferrous metals industries continues.These factors contribute to an oversupply of mercury and the need to find suitable treatment methods for the long term management and storage of mercury and mercury bearing materials."

Jan 1, 2012

By I. S. Thompson

"The discovery of low-grade copper-silver mineralization near the town of Tipperary, Ireland, by Gortdrum Mines Limited was the result of reconnaissance geological and geochemical exploration followed by target delineation from induced polarization surveys.Initially, orientation studies at the Tynagh lead-zinc orebody showed that such deposits could be readily detected in stream sediments and soils using cold extraction analysis for total heavy metals. Numerous areas showing stratigraphical and structural similarities to Tynagh were then selected for reconnaissance geochemical prospecting.The Gortdrum deposit was detectable through the presence of anomalous metal values in stream sediments 3,000 feet downstream; soil sampling indicated an area of 2,000 by 700 feet containing 2 Yz to 20 times background cold-extractable metal values. Induced polarization surveys defined the dimensions and attitude of mineralization.Drilling to date has outlined (under 10 to 20 feet of till) low-grade copper-silver mineralization within Lower Carboniferous limestones and shales which have been faulted against Devonian sandstone. Mineralization ex-tends from surface to depths of 250 to 450 feet and consists of bornite-chalcocite-tetrahedrite and some chalcopy-rite in altered limestones and intrusive dikes.The deposit is geologically analogons to the Tynagh and Silvermines orebodies, but in contrast exhibits a predom-inant structural control. Provisionally, it is postulated that mid-Carboniferous folding and faulting produced the pre-mineralization high porosity via recrystallization, shearing and brecciation. Subsequently, hydrothermal solutions from the west, with a probable eommon origin to the volcanic dikes, were introduced along the fault planes. Although syngenetic causes cannot be exempted, the field relationships favour an epigenetic origin."

Jan 1, 1967

By Rolf Andreas Lauten, Adam Pratomo, Dani Ramdani, Helminton Sitanggang

A universal challenge for the mineral processing industry is the diminishment of high grade ores. Instead, low grade ores, sometimes also containing problematic gangue minerals is the reality. With lower head grades the industry has to put more effort into processing to maintain the output and achieve suitable recoveries. In an effort to reduce the impact of declining head grade, a biopolymer was evaluated as an additive in the gold leaching operation at Antam Pongkor in Indonesia. Laboratory testing revealed that biopolymer usage lead to an increased gold recovery without apparent negative impact on the other parts of the process. Further plant trials revealed both a recovery increase around 1.3% and higher throughput (9%) in the presence of the biopolymer. Some scenarios that can explain these findings will be discussed.

Jan 1, 2014

By Lionel A. York

This paper outlines the type of water-bearing formations encountered in the Prairie Sediments and describes a method for effectively sealing these zones in order that shaft-sinking operations may be carried out with safety. Details are given of the procedure for carrying probe holes ahead of the shaft bottom. These probe or grout holes are employed for establishing a series of overlapping grout covers around the proposed shaft excavation to safeguard against large inflows of water during sinking. The pattern and length of grout covers cannot be standardized, and each cover needs to be specially designed to suit the varying ground conditions. In order to provide effective protection through the Prairie Sediments, the number of holes in any one cover would not be less than 8, and possibly as many as 64 would be required in certain zones. The length of covers would vary from 100 ft. to 250 ft. Emphasis is placed on the need for obtaining accurate geological and water information from exploratory holes, drilled in the shaft vicinity, in order to effectively plan all grout covers.

Jan 1, 1964

By Claude Bazin

The Quebec province in Canada is a major producer of aluminium through electrolysis of alumina. The alumina that feeds the electrolysis cells is mainly imported from foreign countries, where it is extracted from bauxite. Other alumina sources, such as clays, have sometimes been considered as potential substitutes for bauxite. There is a large clay deposit in the area of Murdochville in Quebec, with sulfuric acid and electricity available nearby the orebody, as well as sea port facilities leading to the major aluminium plants in Quebec. These are favorable factors to assess the economics of an industrial plant to produce alumina from clays. This paper reviews some of the processes considered for the extraction of alumina from clays and presents results of the initial work carried out on the clay available from Murdochville.

May 1, 2001

By K. Aziz

The solutions to unsteady-state gas flow in a radial system have been reviewed in order to aid in the interpretation of drawdown data. It has been the practice to evaluate the time and rate conversion constants, directly or indirectly, by using reservoir data. This paper presents a method of determining these constants from drawdown data. A simplified approach to the de-termination for the various boundary conditions is presented. An example of a problem which illustrates the use of this theory appears in the appendix. UNSTEADY-STATE FLOW EQUATION The solution of any unsteady-state flow problem involves (1) the continuity equation, (2) the equation of state of the fluid, (3) the equation of fluid motion and (4) the boundary conditions. For the Darcy flow of a gas in the horizontal radial plane, the equation is when the viscosity, compressibility and permeability to gas flow may be assumed constant and the medium

Jan 1, 1963

By Mayumi Ito

Mineral processing of rare-earth ore from the Dong Pao deposit, Vietnam, was investigated. The ore contained bastnaesite, (REE (rare earth element)) CO3F, as the valuable mineral and barite, quartz, and fluorite as gangue. To establish a mineral processing flowchart, selective comminution, size classification, and magnetic separation were tested. Bastnaesite shows brittle properties and selective comminution was applied to improve the purity of products. The crushed products were classified by decantation, and the overflow product showed high purity of bastnaesite indicating that bastnaesite becomes fines by crushing and that selective crushing can be used to concentrate the bastnaesite. Magnetic separation for the sink product was carried out and the mag-product showed high recovery rates of bastnaesite, indicating that the combination of size classification and magnetic separation is effective.

Aug 1, 2013

By B. H. Weber

"Industry generally has become noise-conscious and is realizing that damage to the human ear is expected to become more costly than any other compensation. Noise control has been recognized as a necessity and, fifteen years ago, in co-operation among different countries, inter-national organizations were set up to co-ordinate measures against dangerous noise and the development of silencing devices began. Rock drills for underground operations were particularly scrutinized because of the explosive nature of the noise developing from air escaping from exhaust. This paper describes the results and the present stage of development in the reduction and control of noise on rock drills, with special application to their use in mines."

Jan 1, 1970

By A. Hayatdavoudi, K. G. Sawant, F. Boukadi

"In this work, we found that contact between shale and water results in development of micro fractures. Based on results of experiments on Pierre shale, we conclude that appearance of micro fractures begin with saturation of capillaries, ionic and diffusive transport of water into the shale clays and once capillaries are saturated, the cause of micro fracture propagation is the conversion of ionic activity/exchange to excess pressure that did not exist before fracking. Based on these findings, the spread of micro fractures appear to be a time-dependent phenomenon which has not been addressed in the existing macro/micro fracture models.INTRODUCTIONShale has often been involved as a hazard in drilling operations. This hazard can be defined as “destabilization” of shale. When contacted with water-based drilling fluids, some shales readily swell and sometimes, cause the wellbore to cave-in, slough, wash-out, close, and pack-off, impeding the drilling by sticking the drill-pipe. However, once drilling reaches the desired depth or length, the casing is set, cemented, and perforated, and then actually we wish to initiate fractures and destabilize the shale formation, using hydraulic fracturing.Clays constitute a major portion of minerals in shale. These clays contain a large amount of free energy which is the main factor for “slick” water adsorption/absorption. In fact, the reason for using “surfactants” in hydraulic fracturing fluids is to make the penetration of the fluid into the capillaries much easier, thus water meets with less resistance to enter the small capillaries. Also, the result of high capillary suction pressure is due to small Angstrom size capillaries, smaller pores and presence of ions and hydrateable metal atoms. The free energy is thus, related to all the above mentioned and other affects. Capillary pressure, osmotic pressure and other pressures are responsible for creating the micro-fractures in shale, thus, increasing the network of micro-fractures which leads to more gas production. The objective of this study is to evaluate the pressures of the individual ions which are released by the diffusing “slick” water into shale. These pressures would be added to the above mentioned capillary pressure, osmotic pressure, bacterially-induced pressures, chemically-induced reaction pressure, pressure due to exchangeable ion-transport, pressure due to release of free energy of solvation and eventually to the pore pressure as suggested by Terzaghi’s equation."

Jan 1, 2015

By G. M. Ross, J. A. Scott, C. A. Laamanen, H. Shang

"Indirect recovery and use of waste heat contained in smelter off-gas is proposed to expand regions available for year-round, on-site production of micro-algae–sourced biodiesel, a fuel that could be used in underground machinery. A dynamic model of an off-gas heat exchanger describes capture and distribution of heat into open, external, rectangular micro-algae ponds. Smelter off-gas contains sufficient energy to maintain large-scale micro-algae cultivation pond temperatures above 15°C, even with winter ambient temperatures below –15°C. Results highlight opportunities that could lie in tapping these heat resources to produce renewable biofuels on-site and sequester CO2 while leaving the industrial process unaffected.RÉSUMÉ On propose la récupération et l’utilisation indirectes de la chaleur résiduelle contenue dans les dégagements gazeux des fonderies pour développer les régions se prêtant à une production toute l’année durant et sur place de biodiesel à partir de micro-algues, carburant dont on pourrait se servir pour le matériel d’exploitation souterraine. Un modèle dynamique d’échangeur de chaleur contenue dans les dégagements gazeux décrit le captage et la distribution de la chaleur dans des bassins rectangulaires ouverts de micro-algues en extérieur. Les dégagements gazeux des fonderies contiennent suffisamment d’énergie pour maintenir les températures des grands bassins de culture de micro-algues au-delà de 15°C, même avec des températures ambiantes en hiver inférieures à –15°C. Ces résultats soulignent les possibilités que pourrait offrir l’exploitation de ces sources de chaleur pour la production de biocarburants renouvelables sur place et pour la séquestration de CO2 sans que cela n’ait d’incidence sur le procédé industriel.INTRODUCTIONMicro-algae that grow in water can efficiently convertsolar energy and carbon dioxide into biomass. This biomass can be up to 50% oils (lipids), which can be extracted and converted into biodiesel through transesterification (Demirbas, 2008). Compared to terrestrial plants that produce similar oils (e.g., jatropha, soybean, and rapeseed), micro-algae represent an order of magnitude increase in areal productivity, do not require arable land, and can be continuously harvested (Rawat, Ranjith Kumar, Mutanda, & Bux, 2013). The potential advantages through the production of biodiesel from micro-algae also include sequestration of carbon dioxide, reduced reliance on fossil fuels, and the co-production of other value-added bioproducts."

Jan 1, 2017

By X. -G. Chen, J. Qin, K. Liu, D. Racine

"Understanding the thermo-mechanical fatigue (TMF) behavior of materials plays a significant role in the safety design of critical components used in aerospace and automotive industries, such as engine blocks and cylinder heads, which undergo the cyclic change of temperature and stress. However, the cyclic changes of temperature, stress and strain make it difficult using the traditional testing methods to accurately simulate the TMF process. In the present work, the Gleeble® 3800 system was successfully applied to develop a reliable procedure to measure the TMF behavior of aluminum alloys. The modified setup together with the new designed program allows the Gleeble system to precisely simulate the cyclic profiles of temperature and mechanical strain. The novel procedure includes the calibration and verification of the TMF setup to ensure the test validity with Young’s modulus measurement, multi-cycle measurement of the thermal strain and zero stress adjustment followed by online monitoring the TMF cycles. The results of the TMF testing of an AA6061 alloy under cyclic temperatures (60–300°C) and various strain amplitudes (0.2–0.6%) were demonstrated. Its TMF behavior was characterized by the typical hysteresis loops and cyclic stress-strain response.INTRODUCTION The thermo-mechanical fatigue (TMF) behaviour becomes increasing important to evaluate the elevated-temperature properties of materials used as the critical components in automotive and aerospace industries, such as the gas turbines (Hu, Shi & Yang, 2016; Moverare, 2007; Segersäll et al., 2015) and engine blocks (Grieb, Christ & Plege, 2010; Javidani & Larouche, 2014). During the cycles of start-up and shutdown of the engines, these components undergo a complex change of loading. Meanwhile, a dramatic temperature gradient exists on the components due to the cooling system. Therefore, the cyclic changes of load and temperature can give rise to the TMF and may limit the use life of such components (Hu, Shi & Yang, 2016; Javidani & Larouche, 2014; Moverare, 2007). Hence, performing the TMF tests to precisely simulate the cyclic changes of load and temperature to understand the TMF behaviours of materials is playing a significant role in the safety design of these components. For TMF tests, two principal types of cycles are generally employed, including the in-phase (IP) cycle where the load and temperature are at the same phase (i.e. maximum load at highest temperature) and out-of-phase (OP) cycle where the maximum load is applied at minimum temperature (Kliemt, 2012; Miller, 2014). The most significant damage mechanisms in engine components are reported to be OP TMF cycles (Javidani & Larouche, 2014; Kliemt, 2012)."

Jan 1, 2018

By Fathi Habashi

Poland has a unique copper industry. Copper sulphide concentrates are smelted in six shaft furnaces to produce matte and in a flash furnace directly to blister copper. Anodic slimes from electrorefining are treated by a modern technology to recover the precious metals. INTRODUCTION Poland's copper industry began in 1950 when the old and relatively small mines Lena and Konrad, located in Lower Silesia, were drained and recommenced production. In 1957 the industry entered a period of rapid development with the discovery of a rich ore body in the vicinity of Lubin and Polkowice which was the basis for the establishment, in 1961, of the Copper Mining and Smelting Combine (KGHM). In 1991 the Combine was restructured into a state-owned, joint-stock company under the new name of KGHM ?Polska Miedz? (KGHM ?Polish Copper?). It consists of three mines, three smelting and refining plants, and one rolling mill, and produces about 4% of the world?s copper and about 7% of the world?s silver.

May 1, 2001

By C. L. Lewis

"The development of computer process control at the Lake Dufault concentrator is reviewed and the on-stream X-ray analysis -computer system is described briefly. Some applications of the computer in metallurgical process control are described.The computer sequences slurry sample streams to the analyzer and translates the analytical results from voltage signals to elemental percentages. The required flotation reagent flow rates are calculated from analyses and mill-feed tonnage rates and the reagent feeders are set automatically to provide such flow rates. X-ray calibration time has been reduced from about 45 minutes to 15 minutes by the use of a computer program. Metallurgical and operating personnel have acquired the ability to program the computer and have extended the system capability to allow the calculation of recoveries, averaging of mill data, application of ore specific gravity in grinding control, control of oxidized ore flotation and the development of an economic recovery program."

Jan 1, 1971

By D. Royston

In SAG mills fed with a variety of ore types, hard packing between the shell lifters can come and go depending on rock type and rock size distribution and the presence of a binder. Packing can appear in all sizes of SAG mills, and can be tenacious. High ball impact forces (depending on ball size) in larger mills may compact and encourage packing. Packing can have a negative impact on milling performance and a change in shell liner design may be required to remove it. However shell liner design changes need to be managed with care to ensure liner reliability. In smaller mills control of packing can extend shell plate wear-life and may help to maintain milling performance in fixed-speed mills through the liner wear-cycle.

Jan 1, 2012