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By D Craw, P Whigham, C Rufaut

Geographic Information Systems (GIS) are computerised management systems for spatial data, offering improved data management, extensive data manipulation techniques and greater understanding of data. At the Wangaloa Coal Mine, South-East Otago, ArcGIS is being used to manage, integrate, analyse and visualise the diverse range of datasets being generated from an interdisciplinary research team. GIS will assist with identifying spatial and temporal patterns associated with the current site rehabilitation strategy. This paper will present an overview of how GIS can be a useful tool for understanding ecological recovery during mine site rehabilitation.   The Wangaloa opencast coal mine, owned by Solid Energy NZ Ltd, was closed in 1989 after more than 40 years of operation. Rehabilitation efforts involving more than 60 000 native plants began in October 2001. At Wangaloa sample points were randomly selected at 100 m intervals and recorded using a differential GPS. Plant, soil and invertebrate data have been collected at each sample point. Plots of 8 - 9 plants have been established within approximately 5 m of each sample point. Since September 2003 seasonal monitoring of plant growth and survival has been carried out. Chemical and physical datasets have been generated from soil collected in June and December 2003 for each sample point. A more restricted dataset is being generated for soil collected on a seasonal basis from March 2004. Plant and soil characteristics from these datasets have been attached to each sample point and GIS layers have been created. Relationships between data layers can be explored based on their spatial patterns. Examples presented from Wangaloa include distribution of planting success and temporal variation; temporal change in pH; interpolated pH map; digital elevation model; relationships between planting success and growth with pH and organic matter. GIS is proving to be a valuable tool on the integrated project at Wangaloa.

Jan 1, 2004

WHILE in the employ of the Broken Hill Associated Smelters and the Electrolytic Zinc Oompanies at their South Melbourne Research Station, the writer was detailed to investigate the principles underlying the Parkes Process with a view of determining:1. The Interdependence of the variables:(a) Quantity of zinc required per charge,(b) Temperature of stirring of each zincing,(c) Silver content of the bullion after first zinculg,(d) Silver content of the bullion after second zincing,(e) Silver grade of the crusts produced for retorting, with reference to the method of working the Parkes Process then in operation at Port Pirie.2. The possibility of effecting improvements in the Port Pirie practice of desilverising, especially with respect to:(a) Silver grade of the crusts produced for retorting.(b) Quantity of zinc required per charge.The method of desilverising in practice at Port Pirie was a two-stage zincing.In both zincings the bullion was cooled to its solidification temperature and the silver crusts which separated from the lead were completely removed.The crusts from the first zincing were retorted, and the crusts from the second zincing were returned to the first zincing of the next charge.

Jan 1, 1925

By P. Dennis, T. Pieters, A. De Kievit, S. Ganguly

TEMCO has been producing manganese ferroalloys in submerged arc electric furnaces for over 40 years. The furnace linings all along have been of conventional insulation type until 2001 when a freeze lining of UCAR concept was installed for a 20 MW Furnace. Continuous improvement of furnace lining performance has been a key component in improving the business competitiveness of TEMCO. The expected minimum campaign life of the freeze lining is fifteen years as compared to the ten years of the conventional linings. The success of the freeze lining is very critical to the quanta and direction of heat flow through the lining that control the freeze protection. Under freeze protection can lead to reduced lining life and over freeze protection, on the other hand, can lead to operating difficulties and loss of smelting efficiency. It was, therefore, necessary to develop a computer based system to monitor and control the freeze protection. The computer based monitoring and control system uses the basic principles of heat transfer, activeX object and heat flux from dual thermocouples and that is reviewed.

Jan 1, 2004

By R. Raghavaraju

Estimation of the dynamic stress field in terms of its amplitude and decay around a blast hole is a key input parameter in all numerical modeling and blast prediction exercises. However, there is very limited information available in literature on these critical parameters, which would be considered essential in any blast modeling exercise. A laboratory-scale experimental study has been carried out in two different rock types to study at very close range the stress wave decay from a blast hole at distances ranging from 3 to 10 borehole radii. The single–hole blasting experiments employed a centrally located detonating cord (5.3 g/m) in 6 mm(1/4 inch) and 10 mm (3/8 inch) boreholes. The coupling medium employed was air and water, in addition to using a thin-walled copper tube in intimate contact with borehole wall to prevent of penetration of explosion gases into the emerging cracks. The paper describes the nature (amplitude and decay) of the transmitted shock pressure and their evolution in the two rock types for these various experimental conditions, which are present to varying degrees in all blasting operations.

Jan 1, 2014

By Randall S. Marks

Bonneville Dam, completed in 1938, included the smallest and busiest lock on the Columbia and Snake River Navigation System. To expedite barge traffic through this restriction, a new larger lock was designed and contracted by the U.S. Army Corp of Engineers.

Jan 1, 1997

By Geoffrey Fosbrook, Donald Phillips, Anil Parikh

The Second Avenue Subway is a $16.8 billion project planned by the Metropolitan Transportation Authority (MTA) in New York City. It will reduce overcrowding and delays on the Lexington Avenue Line, improving travel for both city and suburban commuters, and improving access to mass transit for residents of the East Side of Manhattan. The project is a new, two-track, 13.5 km (8.5 mile) subway extending from Lexington Avenue at 125th Street in Harlem on the north end of Manhattan, to Water Street at Hanover Square in Lower Manhattan. The first phase of construction includes rock tunnels from 92nd Street to 62nd Street and connection to the existing 63rd Street station, three new stations, and track and systems from 105th Street to 63rd Street, allowing service between 96th Street and Brooklyn via an existing Broadway Line. The following describes the Project in detail, discusses the construction challenges addressed in the design, and the initial design/build contract to be awarded in 2005. A discussion of the planned mined construction of two rock caverns and a cut-and-cover station construction are also included.

Jan 1, 2005

By H. Sarvamangala

Biomineralization of manganese on titanium condenser material exposed to seawater has been illustrated. Biom-ineralization occurs when the fouling components, namely, the microbes, are able to oxidize minerals present in water and deposit them as insoluble oxides on biofilm surfaces. Extensive biofilm characterization studies showed that an alarmingly large number of bacteria in these biofilms are capable of oxidizing manganese and are, thereby, capable of causing biomineralization on the condenser material exposed to seawater. This paper addresses studies on understanding the exact role of the microbes in bringing about oxidation of manganese. The kinetics of manganese oxidation by marine Gram-positive manganese oxidizing bacterium Bacillus spp. that was isolated from the titanium surface was studied in detail. Manganese oxidation in the presence of Bacil-lus cells, by cell free extract (CFE) and heat-treated cell free extract was also studied. The study confirmed that bacteria mediate manganese oxidation and lead to the formation of biogenic oxides of MnO2, eventually leading to biomineralization on titanium surface exposed to seawater.

Jan 1, 2008

Behaviour of Bubble Clusters in a Turbulent Flow

Sep 13, 2010

By R. F. Favreau, Patrice Favreau

"A blast with explosives creates vibration waves in the zone around the blast.The prediction of the intensity of vibrations is important because people in the cinity demand that the vibrations do not disturb them, and society imposes limits on the vibrations. The U. S. Bureau of Mines (USBM) showed that the easurement of the particle velocity U predicts the risk of damage from vibrations. A currentapproach of blasters to monitor vibrations is to measure them with a seismograph at several distances S, and create a graph of U vs. S and the explosive charge “W” according to the equation U = K / (S / W)N where K and N are constants that depend on the blast method and the nature of the ground over the distance S. Though useful, this equation is empirical, and the results predicted from it are very variable, as shown by figure 1 which indicates that a prediction of U can deviate significantly from the actual value. Moreover, a minimum of two seismograph measurements at two values of S are required to establish the curve. However, here now exists another very convenient method to predict U; it is with the simulator Vibmas, which is based on the fundamental principles of how a blast reates vibrations. This simulator takes into account not only W but rather all the blast parameters, the type of explosive and the properties of the rock. Moreover, to establish the calculation of U as a function of S, only one seismograph measurement is required rather than two as for the USBM method. This last difference is important because it makes it easy to predict U not only as a function of S, but also as a function of the orientation of S. On the site this allows much safer control of the vibrations, and the use of larger explosive charges which reduce excavation costs. The article presents results from a field case at a hydroelectric project in Canada, where the deviation was very moderate. Use of this vibration simulator on the Web is very easy."

Jan 1, 2015

By Lutz Markworth, Fernando Parra, Wolfram Jaspers

"The worldwide demand of iron ore and the depletion of the high-purity deposits make it necessary to recover ores in increasingly fine size fractions or low Fe content in the feed material. Impurities for Iron ore processing plants are mainly Silica, Al2O3 and Sulfides.There is a copper processing plant in Chile, which has a high content of Fe in its tailings. These tailings will be re-processed to recover the Fe and to produce a pellet feed concentrate. This challenging flotation process was developed by the customer in his own laboratory. Different flotation technologies were tested. The best results were achieved with the PNEUFLOT® (PNEUmatic FLOTation). For a feed capacity of approximately 600 t/h, a flow sheet of two flotation lines with a reverse two-stage Amine-Silica flotation followed by a single stage reverse Xanthate Pyrite flotation was developed.Because of the two impurities the process control is very critical. Not even the reagent dosing has to be flexible for changes in the feed material; also the flotation cell has to be adaptable. Continuous development of the PNEUFLOT® cell with their specific advantages and the elimination of dysfunctions in the PNEUFLOT® cell have led to a growing demand of this type of equipment worldwide for the iron ore industry within the past years.INTRODUCTIONThe worldwide increasing demand of iron ore is mainly caused by China. This has a major impact on all economics worldwide as the metal price indicates. However, not even the iron ore and steel price, but all other commodities prices and the precious metals prices are increasing by a high percentage. Figure 1 shows the iron ore (pellets) price increase for Fe and the import of iron ore by China. Figure 2 shows the imports of iron ore to China."

Jan 1, 2008

By Djavid Mohammad

Over the next several years, the storage capacity of the Metropolitan Water Reclamation District of Greater Chicago?s Tunnel and Reservoir Plan will be increased by 14.8 billion gallons through the addition of two large off-line reservoirs: the McCook and Thornton Reservoirs. The Thornton Reservoir will be constructed at the terminus of Calumet TARP System. The constructed TARP system will be connected to the Thornton Reservoir via connecting tunnels and gates systems. The connecting tunnels will comprise of: an upgradient transition tunnel, steel lined bifurcated tunnel for conveyance and control of flow, downdradient transition tunnel, and energy diffuser at tunnel portal. A large, approximately 250-foot-long, 69-foot-wide, and 40-foot-high, rock cavern will be excavated at an average depth of 320 feet to house the bifurcated tunnel system and associated six large control gates, each 12.5-ft by 28-ft wheel gate. Presented in this article are discussions about the TARP system, the Connecting Tunnels and gates Project, regional rock conditions, evaluation of reservoir?s wall stability for evaluation of tunnel penetration, and design challenges facing during design of the: rock cavern hosting the bifurcated tunnel system and gates and associated tunnels and shaft.

Jan 1, 2008

By Xuejing Xie, Tianxiang Ren

Paper presented at the 28th International Geological Congress held in Washington DC, July 1989 (International geochemical mapping sessions). Standardised stream-sediment sampling procedures have been used in mountainous and hilly terrains. Special sampling procedures were developed for application in remote environments, such as high mountains, desert, semi-desert, karst and loess-covered regions. The diversified analytical methods used in more than 20 analytical laboratories participating in the project have been unified into two multi-element, multi-method analytical systems. A unified data monitoring procedure was developed based on primary and secondary standard samples. To date the project has covered about 4 000 000 km2 and the aim is to complete the coverage within the present decade

May 1, 1991

By Lester G. Morrell

AGAIN in 1963, as in nearly every year since 1946, the Canadian mineral industry has established a new national record in value of mineral production. The 1963 estimated total value of $2,976 million is 5 percent higher than the 1962 value of $2,845 million.2 As in previous years, metals made up more than half the value of total production. For selected years since 1949 the category percentages and total value are as follows: [ ] Crude petroleum, Canada's most valuable mineral product, accounted for 21 percent of the total value of minerals in 1963. In descending order came nickel 12 percent, iron ore 10 percent, copper 10 percent, gold 5 percent, and uranium 5 percent. Asbestos accounted for 5 percent, sand and gravel 4 percent, and cement 4 percent. The complete list of Canada's mineral products includes more than 50 basic commodities.

Jan 1, 1964

By J. Daraisme

Société le Nickel (SLN) exploits the Dôme lateritic nickel orebody at its Tiébaghi operations in New Caledonia. The site geology has an obvious bearing on recovery and metallurgical performance, and the controls are extremely complex at all scales: lithology, oxidation-reduction conditions, mineralogy, and multivariate geochemistry. In that context, establishing an adapted recoverable resource estimation method that is efficient and transparent proves an interesting challenge. The method must address the key notions of: ? Support effect: the exploration data-set can only warrant the estimation of large panels 20×20×3 m3, which are much larger than the selective mining units (SMUs) of 5×5×3 m3 ? Information effect: the selection at production stage uses estimates based on information much denser than that available for mine planning. The problem is rendered more complex in this type of deposit by the fact that the additive variables used for any estimation process (metal accumulation and ore tonnage) are not the ones used to establish the selection at mining stage (i.e. the nickel grade of SMUs, which is the ratio of accumulation on tonnage). Eventually, the selection criteria involve not only Ni grades but also other constituents such as Al2O3, Fe2O3, MgO, and SiO2. The solution presented in this paper is the construction of a platform of SMU multivariate simulations in the saprolitic horizon, together with efficient post-processing aimed at producing the multivariate recoverable resource estimates. The efficiency constraints imposed by the number of blocks to be simulated (1.5 million) lead to resorting to direct block simulations. The underlying multivariate discrete Gaussian model (DGM), the validity of which is tested beforehand, is put to good use to mimic the selection process at the mining stage, by offering the ability to simulate in each block a composite value located at random within the block. Finally, the paper presents the application of a scenario reduction algorithm to pick a representative subset of a few simulations to help appraise the risk attached to the downstream phases (reserve optimization, mine sequencing) of the project. The implementation presented here is for the first generation of the Scenario Reduction plugin built in Isatis software, where measuring the distance between the initial set of scenarios and the reduced set is based on Ni quantities only. Research is under way to adapt the measure to the true multivariate nature of the problem.

Jan 1, 2014

By Charolett Hayes, A. L. Russell, Anthony J. Bednar, Jared Smith, Valentine A. Nzengung, Stephen L. Pilcher

The manufacture of Energetics Materials (EM), including maintenance and demilitarization of munitions causes dangerously high levels of explosives residues to be harbored in building features. The two commonly approved methods of decontaminating energetics contaminated equipment and building features are thermal treatment and steam washing. The current regulatory environment is generally becoming more stringent and unfavorable to thermal and steam decontamination because of their adverse impact on air, soil, and water and their ineffectiveness to completely remove accumulated energetics from foundation cracks, internal and external piping, voids in walls and ventilation systems, and internal cavities of fixed equipment. However, chemical destruction of energetics, especially high explosives, is gaining acceptance as a safer, cost-effective and environmental friendly alternative to thermal and steam decontamination. Organic explosives, including nitramines and nitrate esters are oxidized organic compounds that are susceptible to chemical oxidation and reduction reactions. Under suitable conditions, a chemical reagent consisting of sulfur-based bulk reductants (neutralent) commercialized as MuniRem generates highly reactive free radicals that very rapidly degrade many energetic compounds to innocuous end products while stabilizing metals as the insoluble metal sulfides.

Jan 1, 2016

By G Liu

Seventy-nine gold deposits and prospects have been discovered in theJiamusi region of northeast China, and constitute one of the most important gold metallogenic belts in China. All these endogenic gold occurrences can be subdivided into three main deposit types: 1. porphyry related; 2. metamorphic-intrusive hosted, and 3. sediment-hosted deposit.   The first two types of gold deposit are spatially and temporally related to Mesozoic Yanshanian granitoid intrusions with hydrothermal activity channelled along crustal-scale fissures. The ultimate cause of the Yanshanian magmatism is considered to be the subduction of Pacific oceanic lithosphere beneath the Eurasian continent. In contrast, the chemical sediment-hosted deposit is typified by the Dongfengshan gold deposit, and genetically related to Proterozoic sedimentation and Mesozoic igneous activities.

Jan 1, 1995

By Adrian Rosen

When one thinks of innovation and leadership in wireless communications, one would rarely consider a potash mine to be leading the way. Agrium Incorporated has proven that they are leaders and innovators, as is evident in their recent deployment of a large-scale 802.11 wireless network in their underground potash mine located at Vanscoy, Saskatchewan. 802.11 is an IEEE standard for Wireless Local Area Network (WLAN) technology. Rather than simply replace an aging communications infrastructure, Agrium chose to let technology provide the framework for future success

May 1, 2006

By Taegong Ryu

Nanosized tungsten powder was synthesized by the hydrogen reduction of ammonium paratungstate (APT) in thermal plasma. The effects of operating conditions on the product composition and particle size were investigated. The particle size of synthesized W powder was less than 30 nm in all cases tested. The sintering behavior of the synthesized powder (25 nm average size) was then investigated and compared with those of commercial W powder of 500 nm average size and W powder of 23 nm average size produced by milling the commercial powder. The sintering was done at 1400oC with various holding times. The hardness of the resulting compact from the synthesized W powder (315 VHN) was similar to that from the milled W powder (309 VHN), but the plasma-synthesized powder had a much lower tendency to form cracks. The compacts of both nanopowders were significantly harder than that of the commercial powder (192 VHN).

Jan 1, 2009

Process Study on Some Ag-Cu-Pb-Zn Polymetallic Ore in South China

Sep 13, 2010

The Gippsland Basin, southeastern Australia, has an Upper Cainozoic history of episodic change of hydrology and the related environment, reflected in the geomorphology and surficial deposits of the onshore basin and the hydrodynamically controlled accumulations of petroleum of the offshore basin. Succeeding this episodic pattern, man through a number of activities, has had a sudden and major impact on the hydrology and the related environment. Activities include those directly affecting the groundwater system, such as extraction of fossil fuels with the consequent threat of land subsidence; irrigation and clearing of vegetation and the consequent effect of salinisation; change of land use and installation of septic tanks with resulting nitrate pollution; damming of streams and the consequent reduction in the frequency of floods with degradation of the biological Environment; de-snagging streams and construction of cutoffs with increased stream erosion, modifying wetlands including drainage, with the consequent degradation of their ecosystems; and increase in phosphate and nitrate inputs to the coastal lakes with the risk of their eutrophication.

Jan 1, 1992