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By Francisco J. Sotillo

"The paper point out the fundamentals of surface chemistry used on the design of this organic polymer, and its effect on the rheology of clayishphosphatic slurries in comparison with other available dispersants. Reducingthe viscosity of clayish slurries increases phosphate particles settling rates, and decreases value losses during desliming using gravitational forces. Also presented the improvement of desliming using centrifugal forces by achieving better separation of the ore from the slimes during cycloning."

Jul 31, 2003

By Rajiv Kalra

"The paper point out at evaluating the merits of oflarge geared mills versus gearless driven mills by evaluating the following factors: The capability of currently available systems in terms of power and milldiameter, efficiency in terms of overall electrical power consumed vs mechanical output power, capital cost, running costs, rooling requirements in terms of air versus water cooling and the installation and delivery time"

Sep 12, 2011

By Victor Tenorio

At the present time, the mineral resources in the majority of underground mines are assessed and reported within a deterministic scenario. Irrespective of the techniques utilized for the estimation, the uncertainty in the reporting of resources is limited to their classification in categories such as Measured, Indicated and Inferred, according to a qualitative appreciation that depends on the abundance and quality of geologic information and sampling. Tonnages and grades reported within each category are treated as of fixed or variable precision depending on their classification; nevertheless, this degree of precision is not quantified, which makes it difficult for mine planning and can seriously affect the decisions that are taken on the resources of a deposit. The uncertainty in the resources comes from the lack of adequate geological information and grades, but this lack of information is very difficult to improve or supplement since the information-versus-cost curve increases exponentially

Sep 19, 2006

By Rubén Muñoz

This paper point out the discussion and evaluation of the non-conventional water resources; the discussion of the results of a multicriteria analysis which allows understanding and evaluating the differences; advantages and disadvantages from the technical-economical, social and environmental point of view of the non conventional water supply options: re use of municipal waste water as compared to seawater supply and its two sub options: raw seawater and desalinated seawater. The results show that there are advantages and disadvantages to each approach, but that use of non-conventional water resources is a viable option for mining companies.

Sep 21, 2013

By Gawen Jenkin

The extraction of metals from ores is often an energy-intensive process, requiring either smelting or leaching at high temperature, or the use of large quantities of strong acids or bases that require energy to produce. These processes often produce wastes, in gaseous, liquid or solid form, which require treatment before they can be safely disposed, and this waste treatment requires further energy. Thus there is a need to develop more energy-efficient and environmentally-compatible methods. In this sense, the paper point out that ionic liquids are one such method, and that they can be used to selectively dissolve and recover native gold and tellurium, sulphides and tellurides.

Oct 21, 2015

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 Mustafa Onder

The paper point out that there are two méthods in the design of the long auxiliary ventilation systems. These methods can be summarized as constant fan spacing and constant fan size. If the fans are placed at the end of the duct, leakage will increase due to the high combined pressure.Also The program called SERIP can be used to examine the effects of positioning the fans at varying distances along the duct and determine the appropriate locations.

Jul 17, 2000

By Dario Bernabe

This paper evaluates four open pit mine scheduling programs recently developed and compares them in order to determine if significant differences exist among them. The same input data, which consist of a 3-D block model, an economic set of parameters, and the initial surface topography for a operating copper mine in Southern Peru, was used to test each technique.

Aug 25, 2002

By Marc Leduc

Since co-disposal technology promises to replace conventional tailings disposal methods at sites with high strip ratios or plentiful old dumps. While the mine waste needs to be relatively strong and low in fine material, and chemical compatibility must be assured, when these parameters are satisfied there are no other significant hurdles to its implementation. In this sense, the paper describe the resulting benefits range from substantial reduction in capital and operating costs to reduction or essential elimination of the short- and long-term liabilities associated with tailings dams are impoundments.Since tailings dam failures are arguably the greatest environmental liability and public relations problem in the industry, reducing the quantity of tailings managed behind dams is a worthy goal.

Jul 31, 2003

By Rob D. Morrison

The paper point out the opportunities for improved performance from Mine to Product using a range of technologies developed at the JKMRC. There are several underlying themes: Readily available computing power makes possible instrument like SPLIT, JKFrothCam and the JK/FEI Mineral Liberation Analyser, a large research project is underway applying acoustic monitoring techniques to large mills with the object being to more accurately monitor total mill load and ball load on-line. Taking advantage of these opportunities will require detailed ore characterization, good models and accurate measurement of mine and plant performance.

Sep 13, 2001

By Sridhar Dutta

This paper point out the predictive performance of a relatively new learning model called the support vector machines (SVM) for spatial grade estimation of two grade attributes alumina and silica in a bauxite deposit of India. In developing the SVM model, it was trained with known input-output patterns of training data set which was derived by splitting the entire data set into training and prediction sets using Genetic algorithms (GA). The use of GA algorithms was made because it attempted to divide the data into two statistical similar subsets. The predictive performance of the SVM was also compared with the ordinary kriging technique using the various statistical indices including Mean Squared Error (MSE), Mean Absolute Error (MAE), Mean Error (ME) and the coefficient of determination (R2) on the prediction data set.

Sep 19, 2006

By Glen Toepfer

The paper point out geosynthetic installations as assets, Construction Quality Assurance (CQA) and how both items relate to ensuring a sound installation that should provide a significant return on investment for the owner. Also this elements that are required in obtaining a sound installation and the tangible benefits of a zero-leak geomembrane installation.

Oct 21, 2015

By H. E. Wyslouzil

Column flotation technology was introduced to the market place about thirty ago years as a device capable of producing concentrates that were lower in impurities than those produced by other types of flotation machines. The ability to operate columns with significantly deeper froth beds and the provision of a froth washing system were the main reasons cited for the improved metallurgical performance. Column cells are now well accepted by the industry for cleaning applications, but there continues to be considerable skepticism about their use as roughers. There have been several documented cases of rougher installations which fell well short of predicted metallurgical performance. The reasons for the shortcomings vary from case to case, however they can be generally attributed to incorrect sizing, inappropriate application and or a lack of understanding of how column cells must be integrated into an existing plant or new project. Columns may not be the best choice for every application. In this sense, this paper discusses some of the important considerations that designers must take into account when contemplating the use of columns as roughers.

Sep 12, 2005

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

By Thomas F. Kerr

The La Quinua mill at the Yanacocha mine in Peru has a thickened tailings storage facility that is contained entirely within an active heap leach pad. In this respect, it is unique and unprecedented in the mining industry and provides the operator, Minera Yanacocha S.R.L. (MYRSL), with certain cost, land-use and closure efficiencies. The combined design requires that the leach ore embankments retaining the tailings provide the same high level of stability and security required of major tailings dams. Contrary to standard tailings dam construction, the leach ore in these embankments is placed in thick, uncompacted lifts so that they maintain adequate permeability for leaching. The resultant loose structure makes static and dynamic liquefaction a critical issue, and the key design principle for avoiding a liquefaction related failure is to keep the ore that is saturated or very near saturated when under leach well removed from the outer faces of the embankments and contained behind large unsaturated structural shells.

Sep 14, 2009