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By Vincent Jue

In December 2009, the Italian High Speed Rail Network AV began running over the full 1000 km system length from Turin, at the foothills of the Alps to Salerno, on the seacoast south of the volcano Mt. Vesuvius. It runs through Alpine rivers, highly seismic active zones, mountains, river plains, and through some of the most densely populated areas in Europe as well as some of its most expensive real estate. The Italian High Speed Network?s technical/economic constraints and its regulatory/socio-environmental concerns well may mirror similar obstacles set to confront the nascent California High Speed Rail Program. The two types of constraints must be dealt with together to reach the best construction solution. It is estimated that more than 20% of Italian High Speed Rail Network costs were spent on ground engineering including over 150 km of tunnels, 200 km of viaducts and bridges and 650 km of embankments and trenches. However, it also is estimated that 25% of costs were spent on social and environmental integration of the new rail lines including over 6 square miles of green offsets, 160 km of anti-noise walls, and 300 agreements for socio-environmental work. This paper will look at four examples of innovative ground engineering solutions, each with its own intricate set of constraints: ? Foundation system for viaducts across the ?Po? and ?Ticino? rivers. ? Soil consolidation under railway embankments ? Requirement of short tunnels for physical and environmental reasons ? Construction of railway stations in a confined right of way

Jan 1, 2010

By D. E. Shanks

This U.S. Bureau of Mines (USBM) research simplified an earlier hydrogen chloride (HCI) leach-sparge process developed by the USBM to recover reduction-grade alumina from domestic kaolin clay. Improvements were made by decreasing the initial leaching acid concentration from 25 to 20 pet, decreasing the leaching time from 1 to 2 h to 15 to 30 min, eliminating the solvent extraction step for Fe removal, and eliminating the step to recover the AI content of the bleedstream circuit. A 10-cycle bench-scale experiment of the simplified process showed that the ferric chloride (FeC13) concentration built up to 9.3 g/L in the recycle stream. This did not interfere with any of the unit operations or final alumina product purity because Fe forms stable soluble chloride complexes when sparged with HCI and is easily washed from the large aluminum chloride hexahydrate (ACH) crystals. The reduced leaching time and acid concentration did not decrease Al extraction.

Jan 1, 2010

Compagnie Minière Espérance mines a primary gold orebody in an openpit. The ore is processed through crushing, primary gravity concentration, grinding and secondary gravity separation, generating tailings with remaining fine gold. Analysis of the material in the pond has indicated a residual gold grade sufficient to justify a chemical treatment process to recover the gold. However, direct cyanidation would require a prohibitively large installation for the site, which is located in a remote rainforest environment. It was decided to test the feasibility of preconcentration using flotation. As lab tests proved up the technical feasibility of the flotation process, an on-site pilot operation was carried out to assess the continuous circuit performances, define the best configuration and obtain enough data for industrial circuit sizing. Data collected during the pilot campaign was used for calibrating a process simulator built with the USIM? PAC software. The simulator validated the feasibility of upgrading the existing plant, including the reprocessing of tailings to obtain an acceptable fine gold recovery from a small amount of concentrate.

Jan 1, 2010

By Kanchan Mondal, Anthony (Sam) Spearing, Gopi Bylapudi, Joseph C. Hirschi

"The U.S. coal mining industry uses about 100 million rock anchors per year. ASTM F432 specifies the requirements for rock bolts on mines but does not address corrosion. Corrosion has been found to be an issue in Australian coal mines (Hebblewhite et al., 2003 and Villaescusa et al., 2007), where the problem has been researched and stress corrosion has been found to be a significant cause of rock falls. Corrosion is also a major concern for underground civil construction in the U.S. but has not been considered an issue or adequately researched in coal mines. Underground conditions are conducive to corrosion mainly because of water quality and humid conditions. There is a perception, however, that when bolts are fully grouted, adequate corrosion protection is offered to the steel. Research has shown that this is not necessarily the case, due to the formation of micro-cracks as the resin sets and with subsequent rock movement shearing the resin column. This paper outlines a method to determine the corrosion potential of bolts used in long-term excavations and suggests ways to mitigate such effects based on research conducted in the lab and on three mines.INTRODUCTIONResearch on rock anchor corrosion in mines has not been extensive enough in the past, and the effects of several factors in the mine atmosphere and waters are not clearly understood. One probable reason for this lack of research may be attributed to the time required for gathering meaningful data, which makes the study of corrosion quite challenging.Almost all the rock bolts used in coal mines are made from steel, hence the corrosion of iron needs to be understood. The corrosion of iron is an electrochemical phenomenon with the overall equation"

Jan 1, 2010

By Hugo Cabrera-Real

This work investigated the chemical and mineralogical properties of CaO-SiO2-CrOx-CaF2- MgO slags. Synthetic slags were prepared and the effect of the slag basicity (CaO/SiO2) and MgO contents on the stability of the mineralogical species formed was analyzed. The morphology and composition of the slags were analyzed by XRD and SEM-EDS, whilst their chemical stability was evaluated by leaching with an aqueous acetic acid solution. It was found that in slags with CaO/SiO2 = 1, the main Cr-compound was MgCr2O4 spinel, which forms octahedron crystals. Small amounts of CaCr2O4 and CaCrO4 were also observed. It was found that increasing the slag basicity from 1 to 2 the compounds MgCr2O4 and CaCr2O4 were formed together with the Cr(V)-containing compound complex Ca5(CrO4)3F which forms hexagonal crystals. The results showed that the highest chromium concentration levels in the leaching liquors corresponded to slags with CaO/SiO2 = 2, probably owing to the formation of Ca5(CrO4)3F.

Jan 1, 2010

By Joseph Kennedy

How do terrorists and other criminal bombers acquire explosives to be used in an attack against U.S property and/or citizens? The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) with nearly 40 years of investigating bombings and other explosives incidents, has learned that explosive materials intended to be used in criminal acts are obtained primarily by theft, clandestine manufacture or diversion.

Jan 1, 2010

By T. T. Chen

Copper anodes generated from copper scrap are relatively rich in Sn, Zn and Fe. Because of the presence of oxygen, only trace amounts of Sn occur in solid solution in the copper crystals. Thus, Sn occurs mainly as SnO2, Cu-Sn-Ni oxide and Sn-Ni-Zn oxide in the copper anodes, and Zn and Fe occur mainly as minor constituents in the Sn-Ni-Zn oxide and Cu-Sn-Ni oxide. During electrorefining, these oxide species are liberated from the copper anodes and report directly to the anode slimes. The trace amounts of Sn present in solid solution in the copper crystals dissolve but reprecipitate as Sn arsenate or a Sb-As-Sn-O phase. Accordingly, high Sn contents in copper anodes do not lead to elevated Sn concentrations in the electrolyte.

Jan 1, 2010

By H. Mullani

We have in southeast Kansas a variety of soils underneath which are a variety of subsoils compressed into what is commonly called “ hard pan.” These soils are of six types, ranging from a clay to a sandy loam. The surface soil in Cherokee County and Crawford County, of whatever quality or type is, generally speaking, from 6 to 12 inches in depth. The so-called “hard pan” ranges from the native grass roots to a depth of from 2 to 12 feet, and in some places even deeper than that.

Jan 1, 2010

By Milos Bila

The second half of 2008 and the first half of 2009 brought up important anniversaries. My old passport from Czechoslovakia has a stamp with date 10-10-1968 at 10:00 AM, the exact time I crossed the border between the former Czechoslovak Republic and Austria. This date has an important meaning because I could not come back to my country for the next 21 years. The 40th anniversary of Soviet led invasion, which took place on the 21st of August 2008, revealed some unknown and long time kept secret news.

Jan 1, 2010

By Melinda Channel, Alan W. Weimer, Jonathan R. Scheffe

"There is a need to develop cost effective renewable energy processes for the production of clean fuels that can simultaneously mitigate the U.S. energy/global environmental security issue. If H2 can be obtained cost effectively via the splitting of water using concentrated sunlight, then it’s possible to operate a fuel cell using renewable H2 or to synthesize other fuels based on renewable H2 for generating electricity or for running internal combustion engines. For example, H2 can be reacted with sequestered carbon dioxide (CO2) to produce syngas (H2/CO) via reverse water gas shift (RWGS), i.e. H2 + CO2 ? CO + H2O. The syngas can be catalytically methanated to form synthetic natural gas (SNG) or it can be catalytically reformed to produce liquid fuels such as “green” gasoline via the MTG process (syngas? methanol ? gasoline). The desert SW United States is home to world class sunlight. Fundamental ferrite thermodynamics will be reviewed, an example of the beneficial effect of ferrite surface area on reaction kinetics will shown, and process economics will be investigated for a 100,000 kg/day facility to produce H2.Introduction and Background ThermodynamicsSpinel ferrites of the form MxFe3-xO4, where M generally represents Ni, Zn, Co, Mn, or other transition metals, have been shown to be capable of splitting water according to the two step cycle shown below:MxFe3-xO4 + solar thermal energy ? xMO + (3-x)FeO + 0.5 O2 (1)xMO + (3-x)FeO + H2O ? MxFe3-xO4 + 2H2 (2)This is an inherently clean and sustainable process, as the only net inputs are solar energy and water, and the net outputs are hydrogen and oxygen. Ferrite water splitting cycles are advantages compared to other high temperature water splitting cycles, such as the ZnO/Zn and Mn2O3/MnO cycles, because thermal reduction has been demonstrated at significantly lower temperatures[1, 2]. As a result, overall efficiency may be increased due to the fact that radiation losses increase as the fourth power of temperature, and material considerations for reactor design should be more flexible. Additionally, cycle repeatability has been demonstrated with relative ease as compared to other thermochemical cycles [3-6]. However, the amount of hydrogen per mole that is generated is significantly less than for other high temperature thermochemical cycles due to the fact that only Fe3+ is capable of being reduced at the temperatures of interest[6]. In addition, water oxidation kinetics appear to be very slow, likely due to diffusion or surface area limitations created by near surface oxidation [6, 7]."

Jan 1, 2010

By Hitch M.

Many mining wastes, especially those from the metal mining industry, have traditionally been treated as a matter of little or no value and in practice a cost burden. Some wastes, due to their reactivity characteristics, have emergent values that go beyond purely economic and into the environmentally beneficial realm. This paper discusses the changing paradigm of mine waste management. Such fundamental parameters such as cut off grade, and strip ratio, are positively impacted by the revaluation of waste rock material. Mine rock waste can now be seen as a commodity of value, similar to the underlying ore being mined and influences the economic performance of suitable projects. This valuable material can be used for industrial purposes including acid neutralization as well as the capture and long-term disposal of anthropogenic carbon dioxide. The Turnagain Nickel project, located in northern British Columbia serves as an example of how waste rock material can become an important matrix for carbon capture and sequestration and can benefit economically from it. By producing material that has emergent economic value as well as carbon capture and sequestration capabilities, the sequestration matrix producer is a beneficiary of new carbon credits that have a market value and is looked upon favourably by regulatory authorities and affected stakeholders.

Jan 1, 2010

By J A. H Campbell

AK6 is a Cretaceous aged kimberlite located in the north-east of Botswana, close to Debswana's Drapa and Letlhakane Mines. It was discovered by Debswana in 1969, but was considered unattractive from an economic perspective. In 2003, Debot Prospecting Pty Ltd ('Debot') re-assessed the area and with the advent of new prospecting technology, particularly large diameter drilling ('LDD') and more detailed ground geophysical surveys found AK6 to be of interest. In 2005, the Boteti joint venture was formed between Debot and African Diamonds plc ('AFD'), which covered a number of Prospecting Licenses, including that which contained AK6.

Jan 1, 2010

By D. C. Lynch

While silica ores are generally considered to have little value, those with exceptionally low B and P content have, potentially, significant worth if processed for use in photovoltaics. The sales value of a cubic meter of ?run of the mill? silica sand is $42 per cubic meter (retail and delivered). If the silica sand can be used to produce solar silicon, its value after processing is $34,000 per cubic meter. Factors that impact the suitability of silica for direct processing in production of photovoltaics are examined.

Jan 1, 2010

By Linda Gaines

Use of vehicles with electric drive, which could reduce our oil dependence, will depend on lithium-ion batteries. But is there enough lithium? Will we need to import it from a new cartel? Are there other materials with supply constraints? We project the maximum demand for lithium and other materials if electric-drive vehicles expanded their market share rapidly, estimating material demand per vehicle for four battery chemistries. Total demand for the United States is based on market shares from an Argonne scenario that reflects high demand for electric-drive vehicles, and total demand for the rest of the world is based on a similar International Energy Agency scenario. Total material demand is then compared to estimates of production and reserves, and the quantity that could be recovered by recycling, to evaluate the adequacy of supply. We also identify producing countries to examine potential dependencies on unstable regions or future cartels.

Jan 1, 2010

By J. Hendry, K. Brady, J. Yorzyk

Drawing from the experience of nickel, copper, aluminum and mineral borates, this paper illustrates the business value that the mining, minerals and metals industry as a whole can gain from applying life cycle assessment (LCA) to products and operations. Through the use of case studies, the paper explores how companies and industry associations have used LCA to their advantage: from evaluating capital investments, meeting customer information needs, supporting new product applications, and developing credible marketing information on the environmental performance of their products. It also explores the dynamics of LCA adoption and integration within companies, and provides recommendations to further strengthen institutionalization of LCA.

Jan 1, 2010

By M. J. Farrell

Mining is a significant emitter of greenhouse gases and is the focus of increasing attention from green groups and regulators. Miners need to know their own carbon emissions and how they compare with the rest of the industry. Miners and mining companies need to know where they fit in the emissions curve. Who is in the bottom quartile? This article updates data from minecost.com which detail the specific carbon dioxide emissions for over 200 mines producing 90% or more of western world copper, zinc, lead and nickel in 2009. This data shows the potential impact on mine economics of proposed carbon taxation regimes and emissions trading schemes proposed at COP 15 in Copenhagen during December.

Jan 1, 2010

Shallow ore deposits are mined by surface methods but a depth is reached in the case of most deposits after which underground methods are applied for the extraction of the remaining ore. The determination of this depth and its analysis is the subject of this paper. In order to determine transition depth from open-pit to underground mining on the basis of the allowable and economically feasible overall stripping ratios, an economic-mathematical equation is first introduced. Using the achieved equation and an analytical procedure on a particular two-dimensional hypothetical tabulate deposit, an effective formula is then established. The formula introduced here, together with the procedure adopted, could be used in all similar mining situations by the mining design engineer.

Jan 1, 2010

By Thomas Lardner

Excavation for The Bow, EnCana, in downtown Calgary, occurred between May 2007 and September 2008. A monitoring programme was used to determine the behaviour of the shoring wall, soil and bedrock during the excavation for the 21 metre (69 ft) deep excavation with a footprint of approximately 17,000 m2 (183,000 sq ft). Results from the inclinometer readings indicated that significant horizontal movement due to a weak rock layer and shear band effect. These modes of movement account for up to 100 mm (4.0 in) and 45 mm (1.8 in) of lateral deflection, respectively. Based upon the results of the monitoring programme, rock samples were collected from the weak mudstone bedrock, with great difficulty, to determine the strength and deformation parameters. Results from the uniaxial compression tests indicate a UCS around 830 kPa (120 psi) and elastic modulus between 80 and 180 MPa (11 and 26 ksi). Mohr-Columb parameters were determined to be c' = 340 kPa (49 psi) and f' = 24°. Residual strengths were determined to be c'r = 0 and f'r = 15°. Using the results of the laboratory tests and field investigation records, an initial finite element analysis was conducted. Results of the analysis show good correlation when compared with the observed monitoring deformation, indicating accurate portrayal of rock parameters. Additional analysis and investigation is required to determine the principal horizontal stresses in magnitude and direction.

Jan 1, 2010

By James Cornwell, John A. Elton

"Thermionic induced reactions and radiation resonance catalysis of aluminum and aluminum oxide materials exposed to microwaves and triboemissions will be described and explained from both a fundamental and practical level. Magnetron operation at distinct operating conditions that generates both plasmon and triboemissive radiation will be explained and the resulting tribochemical and radiation resonance catalytic reactions between aluminum, aluminum oxide, water and graphite will be delineated. The generation of hydrogen from these materials using triboemissive radiation and microwaves will be described, and the application of this methodology for hydrogen based technologies will be discussed.IntroductionProtective Systems Directed Energy RadiationProtective Systems, Inc, has developed a new radiation device called the EMR (Electromagnetic Resonator) that has unique characteristics that separates it from traditional microwave and rf radiation devices. The radiation from the EMR device is generated using a modified electronresonance magnetron with proprietary filters and operating characteristics.Electronic Device Shutoff. When electronic devices such as cell phones, computers, and other IC based electronics are placed within the EMR radiation, these devices become non-functional as long as the EMR beam is active. Upon removal of the EMR radiation the devices either become operational again or become operational after a cold start. The devices are not damaged by the irradiation.Faraday Cage Interaction Effect. When any of the above electronic devices are placed in a Faraday cage and activated within the Faraday cage without EMR radiation, they operate normally. However, these devices will still be rendered inoperative when an EMR beam generated outside the Faraday cage is directed at the electronic."

Jan 1, 2010

By P. C. Carrasco

Knowing the origin of the relevant and irrelevant components of the nugget effect is essential to optimize the process under study. This paper describes the causes of the nugget effect and, its dependency on the sample support, sampling density, and on the QA/QC procedures. Several examples of natural and ?human? nugget effect are given. A method to estimate the magnitude of the relevant and irrelevant components is suggested. Finally, the economic consequences of misunderstanding the nugget effect are analysed.

Jan 1, 2010