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By Daniel R. Hack

This paper point out the development of optimized routines for the processing and analysis of field data, continually building a framework for further software development. It also describes the possibilities for future development in the realm of 2D variography for surface water heat flow systems using existing proprietary and academic software packages.

Jul 17, 2000

By Edmundo Alfaro

The paper describes the thiosulfate process for gold leaching like the best non-polluting alternative to cyanide. Thiosulfate is a non-toxic lixiviant and has the ability to complex gold and silver. Copper bearing ores are not harmful for the process and does not suffer the preg-robbing phenomenon like in the case of cyanide. Nevertheless, the process is not fully developed, basically because of the poor understanding of the solution chemistry. Upon thermodynamic considerations and experimental evaluations it was found that the system is unstable; thiosulfate oxidation is unavoidable and ammonia is lost by evaporation. Measures to reduce thiosulfate oxidation include the adequate balance of ammonia and thiosulfate concentrations, adequate pH, additions of sulfite and additions of complexing agents like glycine.

Sep 12, 2005

By Józef Hansel

The paper point out that shaft hoists operated in Polish mines represent the average wolrd standard. In this sense, transport of mining personnel and mined material from increased depths causes no major problems, the number of hoists of considerable loading capacity still increases despite the increase in the shaft depth; the output per one mine hoist has grown considerably and high safety standards in personnel transport are provided (in the last 10 years no life was lost during personnel transport).

Sep 13, 2001

By Patrick High Smith

The paper summarizes the results from geochemical orientation and project surveys in North and South America. The orientation surveys were designed to characterize the soil gas response over buried mineralization and compare soil gas geochemistry with other geochemical exploration techniques for overburden. In addition to successful tests in orientation surveys, soil gas geochemistry has been applied in large-scale exploration programs for gold, copper, and zinc. The studies includes results from several of these surveys, including the Crandon Zn-Cu massive sulfide deposit in Wisconsin, USA, and the Ruby Star skarn Cu deposit in Arizona, USA.

Apr 24, 2001

By Scott Elfen

The degree of saturation in leach facilities and waste dumps can be determined by means of this simple test equipment. A design flow rate is applied to the sample, which is equivalent to irrigation and/or the design storm event. In this sense, the paper point out that the tests were carried out on two different ore sizes from the Pierina Gold mine in Peru. The samples were remolded by using three different densities, simulating different depths within the heap. The ore was subjected to a predefined flow rate, which was equivalent to the design irrigation rate. The flow rate was increased to consider the additional effect of the design storm event during irrigation. In the future, further tests will be performed using different ores samples from operating mines and varying different parameters to help built a database and develop other useful applications from this test, such as general guidelines for maximum irrigation rates for leach facilities.

Jul 31, 2003

By Michael Klug

"In the past the optical sorting in the mining sector has not enjoyed an outstanding and very celebrated position in the industry because of insufficient computer–, sensor– and valve-technologies. Due to the fast development processes in the last years, companies nowadays can offer a high efficient system to the industry. Sensor based sorting is already an outstanding and proven technique and has become an important alternative to either extensive process steps or the widely spread handpicking.The increasing costs for the latter results in manual sorting of more coarse material. "

Sep 1, 2017

By Chris Twigge

The paper point out development and successful commercial introduction of new technologies into a metalurgicall. The discussion that follows examines the overall issues of implementation from a management perspectiva and will highlight areas where key success factors are often overlooked. The framework presented is structured around the following key themes: The prime incentive for introducing new technologies is broadly one of economics, the implementation of new technologies is, to a large degree, a process of risk management and although the implementation of new technologies revolves around technical and economic issues, in the end the decisiva factor is people. Proper recognition of the human factors is critical to success. In this sense, the above principles are discussed in the sections that follow and include a number of examples to illustrate how technology can be successfully implementad and how it can fail.

Oct 6, 1999

By J. B. Greenwood

The paper point out some reasons why contract mining should not achieve the same success in Latin America as it has in Australia. In this sense, any reasons are: the size of operation, mining industry employees bonus scheme, the privatization of nationalized mining assets, general sales tax and the mining unions. Therefore, great deal depends on the attitude or "mindset" of a company's employees. lt is strongly my view that the attitude with which a contractor approaches a job will give rise to a superior mindset amongst its employees when comparad to those from most mining companies. The value of this cultural difference is significant and should never be underestimated. lmportantly, it doesnot only manifest itself in a more productive workplace: it is invariably the case in Australia that the safety achievements of contract miners are superior to those generally expected from the mining industry at large.

Oct 6, 1999

By Yvan Guzmán, Víctor Ascuña, Federico Calisaya, Giraldo Carpio

El presente trabajo tiene como objetivo presentar el diseño de un concentrador centrífugo gravimétrico usando aire como fluido, que será usado en la recuperación del oro fino presente en los minerales auríferos. Se utiliza el modelamiento matemático fenomenológico como herramienta para el diseño del concentrador.

Sep 1, 2017

By Robert Shaw

"The paper point out the volcanogene and sediment-hosted base metal deposit from the Colombian cordilleras have been considered in the light of tectonogenic models for these deposit types, based upon the recent re-interpretation of the geology and tectonic assembly of the Northern Andean Block by Cediel and Cáceres and Cediel. Numerous distinct propitious metallogenic settings containing important but subexploredbase metal mineralisation are manifest as a result of the tectonic evolution of this northern-most sector of the Andes. Some examples include like a) Central African Cu (U) Belt - type mineralisation within the back-arc region of the early– middle Paleozoic Cordillerantype Quetame Orogeny, b) numerous SEDEX and Sediment-Hosted Zn (Pb-Ag) and Cu (Ag) styles of mineralisation associated with various phases of continental and continental margin rifting during the late Paleozoic to Mesozoic Bolívar Aulacogen, and c) various Cu-Zn-Pb (Au, Ag) Volcanogene Massive Sulphide manifestations associated with intra-oceanic magmatic arc development and accretionary tectonics during the Meso-Cenozoic Northern Andean Orogeny. "

Apr 22, 2003

By Jean Legault

ZTEM is a natural field airborne EM technology that is in its 10TH year of service and is widely used for porphyry copper exploration around the world, yet is still considered a new technology. ZTEM uses EM fields generated by worldwide thunderstorm activity as is primary source field. Its large depth of investigation (>1km), its sensitivity to weak lateral resistivity contrasts and the relative simplicity of its EM fields for computer modelling are among its greatest attributes. ZTEM has helped discover blind porphyry copper deposits and is also widely used in unconformity uranium, epithermal gold and geothermal exploration around the world.

May 1, 2008

By Marcelo Rocco Salinas

La presencia de arsénico en aguas de mina (efluentes mineros) es una preocupación constante en el Perú, debido a que los receptores superficiales de estos efluentes son utilizados para bebida de animales, o riego de plantas. Las razones de la presencia de este metaloide están asociadas a la mineralogía propia del país. En este manuscrito se presentan los resultados de pruebas a escala industrial realizados en una compañía minera ubicada en el distrito de Canarias, provincia de Víctor Fajardo, departamento de Ayacucho.

Sep 1, 2017

By Dan W. Bench

PCBs are hazardous not only to human health and the environment but also to the mining industry because of potential worker exposure and improper disposal liabilities. In this sense, the paper point out the identification, management, and proper disposal of pcb-containing electrical equipment used in mines. Also it point out alternatives to PCB dielectrics, storage, and disposal. The use of PCBs in mines has been documented during U.S. Environmental Protection Agency Region 8 mine inspections and it used as dielectrics in transformers, capacitors, and fluorescent light ballasts are common throughout industry worldwide.

Sep 14, 2009

By R. W. Lawrence

This paper provides a brief overview of biogenic sulphide reagent production from elemental sulphur, discusses the main advantages of recovering metals and treating heavy metal pollution using biogenic sulphide, and presents operating results from commercial plants.

Sep 12, 2005

By Alex Jankovic

The paper point out the high capacity processing of a hard, fine grained silica rich magnetite ore with several circuit operations was carried out to assess the energy efficiency, operating cost and project economics expressed through NPV. The result of the study autogeneuss grinding technologíes offers significant benefits over the conventional grinding circuits options.

Sep 21, 2013

By Joseph W. Ruetz

The paper describes the San Nicolas deposit, México. San Nicolás deposit is the most important VMS deposit discovered in Mexico to date, and a major deposit on a global scale. The discovery of San Nicolas resulted from the early recognition of VMS mineralization in a region not known for this style of mineralization, and the flexible use of appropriate exploration technology.

Apr 24, 2001

By Leonard Harris

"One of the reason to its decline are nationalization of some of the United States company mines in the developing world has been the spectacular rise in extreme environmetalism, which has warped public opinion about mining and delayed and denied exploration and operating permits of many projects in the United States. In this sense, the paper point out this “disease” is speading rapidly to Latin America but can be stopped or atleast controlled, by the union of mining company forces with the strong backing of trade organizations along the lines which have been succesfully instituted in the United States. "

Jul 31, 2003

By Reinhold A. Errath

"The paper describes the problem related with contradiction to the development of sag mills, which one are becoming bigger in size almost every year. In this sense, the concentrator plants are being built more and more in remote areas where the power supply and network conditions are not necessarily covering the needs for the operation of such plants. It also illustrates the permissible tolerances in terms of commutation of the powerelectronics, based on already realized installations. Finally the paper gave an overview about the technical impact of a strong versus weak networks."

Jul 31, 2003

By Edmundo Alfaro

"The paper point out about on the use of ion exchange resins for adsorption of gold from ammoniacal thiosulfate solutions. In this sense, the gold can be recovered from ammonium thiosulfate solutions with strong base resins. The amount of gold loaded onto the resin in a batch process is a function of gold concentration in solution, amount of resin, volume of solution, copper and competing ions concentration in solution. Thiosulfate concentration in leaching solution has influence on gold loadings onto resins; in contrast, ammonia concentration in solutions has no influence on gold loadings. Gold seems to be loaded onto the resin preferentially over copper - thiosulfatecomplexes and also over thiosulfate ions. Polythionate ions strongly compete with gold and copper thiosulfate complexes for resin sites. This causes reduction on gold and copper recoveries from the leaching solutions. Even more, polythionates are produced in leaching solutions when thiosulfate is oxidized by the action of both copper and oxygen. "

Jul 31, 2003