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By D. M. Muir

Many plants produce iron(II)/(III) waste liquors which must be treated by neutralisation and precipitation to remove the iron. Iron can be precipitated as crystalline goethite or jarosite by controlled oxidation at low pH and as magnetite by controlled oxidation at high pH, but only at elevated temperatures (>70°C). This study focuses on the characterisation and settling properties of the iron oxides produced at ambient temperatures using various neutralising agents in order to improve the performance of thickeners. It was found that two-stage addition of caustic to FeC12 solutions produced a fast settling material characterised by Mossbauer spectroscopy and XRD as maghemite and magnetite. However, lime and magnesia additions resulted in more ferrihydrite formation and much lower settling rates because of the enhanced oxidation of Fe(II) by air. Settling rates decreased significantly as the proportion of Fe(III) to Fe(II) in the liquor increased. The mechanism of iron oxide precipitation is discussed together with some reasons for the different behaviour of the neutralising agents.

Jan 1, 2006

By Michael W. Russnak

Productivity and operating expenses are everything when it comes to judging how well your mine and company are doing. Stakeholders are always looking at these numbers and trying to understand if productivity is improving, if operating costs are trending downward and what you are basing your decisions on. o make improvements you first need to understand how you are performing. If you can?t get this basic information, you will never improve. You will not be able to make simple decisions related to maintenance, operations or production. Forget about planning, as you will only be guessing based on the numbers some stakeholder or your executive wants to see. The problem miners run into is not that the data doesn?t exist; it does, but typically it?s raw, it?s everywhere and its volume is huge. Today there is more on-board computing capability in shovels than we had on our desktops three years ago. Add other mobile equipment, plant systems and multiple OEM vendors to the equation and the challenge is daunting.

May 1, 2007

By Knud Sinding

Environmental reporting by mining firms takes many forms and change frequently. The objective of these reports is related to increasing the legitimacy of mining firms with their diverse stakeholders. This study, focusing on internet-based reports, shows that there are considerable variations in reporting. This phenomenon is interesting because it belies the efforts pursued by leading industry members under iniatives such as the Global Mining Initiative and the Mining, Minerals and Sustainable Development project. The observed variation, both internally among reports and between reports and other industry policy statements, suggests that the industry needs to explore the possibilities for more convergence in terms of reporting quality. Based on theoretical constructs from the management literature we present a series of arguments defining necessary and sufficient conditions for durable and well-institutionalized reporting practices and standards.

May 1, 2002

By J. L. Jambor, T. C. Birkett, W. D. Sinclair

Abstract -The rare-earth elements (REE) form a significant part of the group of so-called "high­ technology" metals whose glamour has attracted both the scientific community and the mining industry. Despite this attraction, world production of REE declined abruptly in 1985 and only recently has begun to approach production levels of 1984. The decline in 1985 was primarily due to decreased demand for light REE used as catalysts in the production of lead-bearing gasoline. Incorporated within the current trend toward increased production of REE is an increasing demand for higher value elements such as yttrium and other members of the heavy REE group, and for specific REE rather than mixed products . The former demand has made some Canadian deposits and prospects economically attractive despite a surplus of REE reserves on a world scale. The chief attractions of Canadian deposits such as Strange Lake, Labrador-Quebec, Thor Lake, Northwest Territories, and Kipawa, Quebec, are that they are relatively rich in yttrium and other heavy REE compared to light REE, and that they offer a potential security of supply to counterbalance the rapidly escalating dominance of China in the world market.

Jan 1, 1992

By C. Siac

"It is a widely held view that in the 21st century, the mining industry will be dominated by a relatively small number of large companies, truly global in scope and internationally staffed (Gooding, 1997). Interestingly enough, most of the exploration and exploitation activities are being carried out by junior and major mining companies from common law jurisdictions in civil law countries, in particular in Latin America, where in recent years, the region has ranked first as a destination for exploration dollars, thanks to the reforms undertaken by some countries to amend their legal framework to attract foreign investment. From a lawyer’s point of view, this is where the main challenge lies: how to bridge the gap between the two legal systems.In order to avoid pitfalls, common law lawyers should be more diligent and proactive when dealing with civil law jurisdictions, given the different systems of law, standards, traditions and customs. Common law lawyers cannot be expected to be well-versed in civil law but they should not be completely unfamiliar with it either. A balance should be struck to ensure clients’ needs are professionally taken care of and that common law requirements and standards are met."

Jan 1, 2003

By Christoph Mueller

Broad band mine communication today is characterized mainly by individual solutions, which have in common their long development phases and their high cost for development, operation and service. The use of Ethernet and TCP/IP on the other side provides an uniquely price efficient combination of high bandwidth open networking, universal use and accessibility of cheap development tools, especially because it forms the technical infrastructure for the worldwide Internet. TCP/IP and Ethernet assures reliable networking however it is not able to guarantee the latency timing of forwarding network information. Therefor, the network design requires strict load limitation and application level traffic control especially if moving equipment has to be manually remotely controlled via the network. To optimize the use of bandwidth on mining networks using load limited, ?bandwidth wasting? local Ethernet segments, long distance broadband traffic should be carried out using more efficient, deterministic communication backbones providing a guaranteed quality of service for each of the physically separated networks. Open networking and broadband systems however may lead to the anticipation that any demands on bulk data or multimedia traffic can be fulfilled in the future. This definitely will not be the case as the bandwidth demands of applications will be growing as least as fast as the bandwidth provided by communication systems. Looking on those problems from an overall system integration perspective, machines and equipment in the future have to be equipped with intelligent computing devices capable of an intelligent local data preprocessing. Such ?Embedded Machine Information Servers? running commercial computing power in the future will be the intelligent bridge between open networking and a secured, high safety local automation system. These ?Embedded Machine Information Servers? then also can make advantage of intelligent video and audio data preprocessing to store and transmit multimedia information ?on demand? or when the application requires it. Summarizing the potential for the future Ethernet based networking together with powerful communication backbones and intelligent local data preprocessing on the machines in the future will lead the way to integrative, reliable and cost efficient mine automation solutions.

May 1, 2002

By W. A. Lang

Introduction Under our present civilization, industrial developments will be greatest in those areas in which energy .can be most economically produced and efficiently used, where labour is in adequate supply, and where markets for the products of industry are available. A knowledge of fuels- the present major sources of energy- and of their utilization is therefore of vital importance. With that in mind, the aim in this paper will be to outline the known reserves of fuels in Alberta, to give their characteristics, to indicate the markets served by each, and to offer some suggestions for the future development of the coal industry. The paper should be regarded as a compilation of published data rather than as an original treatise. Alberta is richly blessed by having large reserves of mineral fuels. The estimated reserves of coal are 46,562 million tons. Alberta is the oil and gas province of Canada. The world's largest deposit of bituminous sand occurs along the Athabaska river in Alberta. In addition, there are large areas of forested land in the northern and western sections of the Province, and the rivers serve for the development of hydro-power.

Jan 1, 1949

By T. T. Ni

FOR MORE THAN 200 years, the Kochiu district of Yunnan province has been, and it still is, the hub of China's tin industry. The district produces annually from 80 to 90 per cent of that country's out-put of tin, which averages about 9,300 tons a year and places China fifth among the tin producing nations of the world. The tin ore reserves of the country are estimated (1) at 1,873,370 metric tons, of which 1,500,000 tons are in the Kochiu district. The mill of the Yunnan Consolidated Tin Corporation, described in this paper, is the only one of its kind in China. MINING AND SMELTING There are only two tin mines in the Kochiu district operating with modern equipment -the Hsin-Chang and the Lao-Chang, both owned by the Yunnan Consolidated Tin Corporation, a government company. The Hsin-Chang mine has four working levels with cross-cuts 6 ft. by 6 ft. and is equipped with steel mine cars and trucks to haul the ore. The ore is hoisted to surface in a three-compartment shaft and transferred to the mill by a 4-kilometer aerial tram. The Lao-Chang mine has two circular shafts 656 feet apart, each equipped with two cages. Haulage-ways 1,600 meters and 1,000 meters long, respectively, have been driven to the southwest from these shafts and are connected by three cross-cuts.

Jan 1, 1951

By Masami Nakamoto

Controlled thermolysis of gold(I) thiolate complex, [C14H29(CH3)3N][Au(SC12H25)2], at 180 °C for 5 h under an N2 atmosphere produces novel gold nanoparticles passivated by alkyl groups derived from the precursor complex, the TEM photograph of which shows spherical particles with average diameter 26 nm. Since Brust et al. reported the two-phase reduction of AuCl4 - by NaBH4 to afford monodispersed gold nanoparticles passivated by alkanethiolate ligands (1), plenty of preparative investigations on gold nanoparticles (2,3) and its surface modification (3,4) have appeared, because of their potential applications in microelectronics (5). However, those preparative methods generally involve the reduction of AuCl4 - by reducing agent NaBH4 in the presence of suitable organic stabilizers such as alkanethiol (1-4), phosphane (5), quarternary ammonium salts (6), surfactants (7) or polymers (8). On the other hand, O?Brien et al. recently reported the preparation of organically capped gold nanoparticles at 190 °C, where tri-n-octylphosphine oxide and/or n-octadecylamine are used both as a reaction medium and as a passivating ligand (6), but this procedure also needs NaBH4 as reducing agent. Our strategy of novel preparative method of gold nanoparticles is the combination of reductive elimination of thiolate ligands and simultaneous attachment of organic moiety on the growing nuclei. Gold(I) thiolate complexes with ammonium cations were useful for our preparative method. We now report the controlled thermolysis of gold(I) thiolate complexes, [R(CH3)3N][Au(SC12H25)2] and [R(CH3)3N][Au(SC6H4-p-R?)2] (R= C14H29, C12H25; R?= C8H17, CH3), under an N2 atmosphere, where the powder of gold(I) thiolate complexes completely melts to afford the precursor liquid and then the liquid gradually decomposes. In spite of no use of reducing agent and solvent, reduction reaction is thermochemically induced to afford novel gold nanoparticles passivated by alkyl groups rather than by alkanethiolate ligands. Figure 1a shows a typical transmission electron microscopy (TEM) image of gold nanoparticles prepared by thermolysis of [C14H29(CH3)3N][Au(SC12H25)2] at 180 °C for 5 h, indicating a controlled growth of spherical gold nanoparticles. As shown in Fig. 1b, these spherical gold nanoparticles display the size distribution ranging from 5 to 50 nm. Although the particle size is larger than that of thiol-derivatized gold nanoparticles (less than 5 nm) prepared by NaBH4 reduction (1-3), the aggregation of gold nuclei is smoothly regulated and the growth of core gold is limited to be 26 nm in average diameter in spite of thermal procedure.

Oct 1, 2003

By A. Kapoor, L. Morin, S. Mortazavi, P. Béedard, Gould. W. D., A. Kuiper

The degradation of thiocyanate in a simulated gold mill effluent was studied using a laboratory scale rotating biological contactor (RBC). Complete SCN- removal was obtained at temperatures of 8 and 12°C, and a hydraulic retention time of approximately 3.3 h. The NH4+ produced by thiocyanate hydrolysis was oxidized by nitrifying bacteria to NO2 and NO3-. The HS- produced by thiocyanate hydrolysis was chemically and biologically oxidized to elemental S, which was subsequently biologically oxidized to sulfate. Incomplete sulfur oxidation occurred in the RBC, particularly at 8°C and elemental sulfur deposition was observed on the RBC disks. The RBC feed exhibited toxicity to rainbow trout but the RBC was effective in removing the acute toxicity of thiocyanate.

Jan 1, 2005

By M. King Hubbert

"The present large-scale use of energy and power by the human species represents a unique event in the billions of years of geologic history. Furthermore, in magnitude, most of the development has occurred during the present century. In the United States, the peak in the rate of petroleum production occurred in 1970 and that for natural gas is imminent. The peak in the world production of crude oil is expected to occur at about the year 2000 and that for coal production at about 2150 or 2200. For other sources of energy and power, water power, geothermal power and tidal power are inadequate to replace power from fossil fuels. Nuclear power, based on the breeder reactor and utilizing lowgrade deposits of uranium and thorium, has a larger potential than the fossil fuels, but it also constitutes a large perpetual hazard. The largest source of energy available to the earth is solar radiation. This source has a life-expectancy of a geologic time scale, is nonpolluting and is larger in magnitude than any likely requirements by the human s pecies. In consequence of the large supplies of available energy, the period since 1800 has been one of an unprecedented exponential industrial growth. This also has been accompanied by a world-wide ecological disturbance, including that of the human population. It can easily be seen that such a period of growth must be ephemeral in character and, in fact, is now almost over. One aspect of this transition from a state of exponential growth to a state of nongrowth is the present alarm over an ""energy crisis."" Actually, the world's present problems are by no means unmanageable in terms of present biological and technological knowledge. The real crisis confronting us is, therefore, not an energy crisis but a cultural crisis. During the last two centuries, we have evalved what amounts to an exponential- growth culture, with institutions based on the premise of an indefinite continuation of exponential growth. One of the principal consequences of the cessation of exponential growth will be an inevitable revision of some of the tenets of that culture."

Jan 1, 1973

"The Upper Mannville unit commonly consists of interbedded marine and non-marine sands and shales, but in northwestern Alberta the unit consists of marine shales of the Spirit River Formation. A thick tongue of marine shale (Clearwater Formation) ex-tends eastward into the Athabasca area below sandy Grand Rapids beds. Correlation of Upper Mannville rocks to the southeast is difficult, but in the Cold Lake area a thick sandy depositional cycle (Mannville ""C"" of this paper) appears to be approximately correlative with the Clearwater Formation. In the Lloyd-minster region, tongues of marine sedimentary rock occur in the lower part of the Upper Mannville unit. Most of the Upper Mannville oil occurs in the Grand Rapids Formation at Wabasca, in the thick ""C"" unit and younger Mannville sands at Cold Lake, and in the Sparky and General Petroleums sands of the Lloydminster region (Figure 2).The Lower Mannville unit was deposited on an erosional surface of considerable relief that truncated the Jurassic and older strata of the Western Canada basin. Continental, probably fluviatile, sedimentation persisted over much of the Western Canada basin during deposition of the Lower Mannville unit, but an Arctic or Boreal sea lay over part of northern Alberta. At the end of the depositional episode, the sea transgressed southward and eastward (Figure 3) and re-worked the Bullhead and McMurray sands of northern Alberta into the glauconitic Bluesky and Wabiskaw sands. Topography on the sub-Cretaceous erosion-al surface had a considerable effect on the deposition of the Lower Mannville (Rudkin, 1965), and the highest hills on this surface were not completely on-lapped by Lower Mannville sediments (Figure 3). The coarser elastic material was derived both from a western Cordilleran region and from an eastern Canadian Shield region (Glaister, 1959, p. 620; Mellon, 1956)."

Jan 1, 1966

By A. Sokolov, E. Hasikova, V. Gostilo, V. Titov

Introducing online X-ray fluorescence (XRF) analyzers in the mining and processing industries can lower costs and improve the representativeness and speed of analysis. The applicability of the CON-XTM industrial conveyor XRF analyzer for continuous measurement of potassium content in process materials was demonstrated at various stages of potassium muriate (MOP) production. The CON-X analyzer produced reliable and accurate results for sylvinite ore (27–36% KCl), MOP cake after flotation (88–97% KCl), and NaCl residue (1.5–5% KCl). Tests of the analyzer at an MOP-producing plant showed a < 0.5% difference between online and laboratory results.

Jan 1, 2014

By G. S. Crawford

Forecasts prepared by the B.C. Research Council for the National Harbours Board suggest that mineral shipments through B.C. Lower Mainland port facilities will increase more than four-fold, from 6 to about 25 million tons, during the decade 1965 to 1975. The longer term outlook is for a six-fold increase to about 35 million tons by 1985. In 1967, minerais accounted for more than one-third of the total deep-sea traffic tonnage, nearly as much as grain. By 1975, the minerals' share will be about half the total. The principal items are exports of potash from Saskatchewan, and of coal and sulphur from Alberta and British Columbia. Additional exports include copper and other mineral concentrates and propane. Imports are chiefly salt and phosphate rock. Coastal traffic in such items as cement, sand and grave!, and limestone totalled 3.3 mil-lion tons in 1967. They will continue to be of major importance, but do not have the spectacular growth potential of the deep-sea traffic.

Jan 1, 1968

By Manjeet Chowdhry, Qingxia Liu, Phillip Choi, Zhenghe Xu

Computational chemistry methods, such as density functional theory (DFT), are powerful tools to quantify reagent-mineral interactions encountered in sulphide mineral flotation. A quantitative relationship between theoretically calculated parameters based on chemical structure of collectors and their reactivity with different metals/minerals can provide valuable insights for design and development of more powerful and tailor-made reagents offering enhanced metal/mineral selectivity. DFT calculations at B3LYP/6-311++G(3df,3pd) level were employed to elucidate the reactivity of neutral sulphide collector reagents, including thionocarbamates (TC), thioureas (TU), xanthogen-formates (XF), dialkyldithiocarbamates (DTC) and dialkyltrithiocarbonates (TTC) with different heavy metal ions (Cu2+, Zn2+ and Pb2+) in solution. The extent of delocalization of lone pair electrons of heteroatoms (attached directly to C in C=S) over C=S group was found to be the dominant factor in determining the collector’s reactivity. Order of reactivity was established as: TU > TC > XF > DTC > TTC. All the collectors showed superior affinity towards copper followed by lead. Unidentate binding was observed through sulphur atom except for xanthogen-formate for which bidentate binding mode was observed. Effect of nature of substituent groups at N and/or O atom on reactivity of thionocarbamate and thiourea was also investigated. The results obtained through DFT calculations are consistent with the experimental data reported in literature.

Jan 1, 2015

By A. A. el-Geassy, A. A. el-Tawil, Hesham M. Ahmed, Bo Bjorkman

The Iron and steel industry is one of the most intensive energy consuming processes. The majority of iron making processes is now directed towards the uses of fossil-based energy sources like coke, coal and oil. Recently, emphasis has been paid to replace part of fossil- based energy sources with renewable biomass-derived reducing agents. In the present work, the possibility of the effective use of woody biomass in carbon-iron oxide composites was investigated. Wood powder was carbonized in N2 atmosphere at 300 up to 450oC. The carbon content in the produced bio-char increased with temperature. The porosity of the char arises from maintaining the cellular structure inherent in wood biomass increases with temperature. The reduction behavior of four iron oxide-bio char composites having different fixed carbon content were carried out non-isothermally up to 1200oC in Ar atmosphere using thermogravimetric anlyser (TGA). Quadruple mass spectroscopy (QMS) was also adopted to measure the CO, CO2 concentrations in the off gases resulted during reduction process. The effect of volatile matter on the reduction of iron oxide was intensively studied. The different phases developed in the reduced product were identified by X-ray diffraction (XRD). The reduction of composites was found to proceed in a stepwise manner (Fe2O3?Fe3O4?FexO?Fe).

Jan 1, 2015

By G. R. Webber

CHEMICAL AN AL YSIS by x-ray emission spectrometry has become increasingly important during the past few years. The method is analogous to optical spectrography ?with x-rays being used instead of light and should not be confused with methods of x-ray diffraction used? for identification of minerals and chemical compounds. X-ray emission spectrometry has many advantages for both qualitative and quantitative analysis. Its optimum concentration range is higher than that of the optical spectrograph, and the group of elements which can be detected is not identical to that which can be detected by the optical spectrograph. Elements which can be detected by the x-ray spectrometer are those elements from magnesium (atomic number 12) to uranium (atomic number 92) in the periodic table. The lightest elements in this range have low sensitivities and more specialized equipment is necessary for their detection than for the heavier elements. A large number of applications of x-ray analysis have been directed toward the analysis of ores, metallurgical products, and related materials (see References at end of paper). A more complete bibliography is presented in the Norelco Reporter, Vol. 3, 1956, pp. 37-39. The periodicals Analytical Chemistry and Applied Spectroscopy are a good source of current articles and references.

Jan 1, 1957

CORPORATE SOCIAL RESPONSIBILITY CSR is about how companies manage the business processes to produce an overall positive impact on society. - Indentured work, sexual slavery, fair trade, organic growing, business ethics, environmental issues, ?Right to know -Right to decide?, AIDS activism, civil society - Balancing stakeholder issues - Government responses Who are the bad guys? Where are the threats?

May 1, 2010

By K. Iturralde

The topic of this article is the automation and robotization in refurbishment processes of industrial buildings. The need to mold these production spaces is quite universal. Particularly in the regions with a high industrial development and with a lack of buildable land, there is a need to convert this kind of spaces into an improved production system. The latest developments can be a useful tool for achieving a more efficient way of reforming this type of construction. On the one hand we have the digital or computerized 3D Laser Scanning (Computer Aided Measurement) that allows an accurate 3D modeling of the entire building. On the other hand, the project management using BIM (Building Information Modeling) could provide an easy design of each of the elements of the refurbishment. Finally, through the production of construction elements using robotics as jig or for CNC (Computer Numerical Control) we achieve a neat production of each element. How can be all those technologies applied in the refurbishment or expansion of industrial buildings? The research takes a first approach and analyzes industrial buildings that can be called generic or not specialized. To narrow the field of refurbishment, three major factors are defined. The first is to minimize the bill of the energy consumption of the buildings. This could be done either insulating the envelope, reducing the waste-volume to be conditioned climatically or creating facilities for energy production. The second is that the refurbishment or expansion of industrial buildings should try not to interfere on the production process that takes place in the building. In other words, the assembly of the elements in the construction site should be quick and easy, causing the least of disturbance at the workplace. Finally, the research makes an approach towards a robot integrated industrial or productive building .

Aug 1, 2013

By Dianne M. Lapierre

Mining firms in Canada are increasingly incorporating the social and environmental interests of their stakeholders into their projects in an effort to become more sustainable. Such initiatives have included negotiating Impact and Benefit Agreements (IBAs) directly with would-be impacted, often aboriginal, communities near resource developments in the Canadian north. Why does a mining firm take on this extra time-and cost-intensive initiative when governments and regulatory measures are in place to address social and environmental issues? Past research has paid little attention to the corporate rationales for IBAs. Based on document review and interviews with mining executives, this study investigates the rationales of mining firms that ?over-comply? with legislative requirements by negotiating IBAs or similar types of agreements with communities. The results indicate that mining firms increasingly recognize IBAs as an intrinsic part of the permitting process. When queried, executives regularly identified the negotiation of agreements as ?the right thing to do?. While this response could be read in ethical terms, a commercial rationale is also clearly present. By building strong relationships with nearby communities, addressing community concerns, and directing benefits to local people, all of which are explicitly achieved with an IBA, mining firms are maintaining their long-term financial viability, thus their sustainability, within an evolving industry.

May 1, 2008