The mechanisms of conversion to elemental sulfur, sulphites, sulfates and others; they are diverse, leading to the formation of sulfuric acid and therefore, to the acidification of the medium. Based on these characteristics, acidophilic bacteria are considered as sulfur chemolytotrophs, since they obtain their energy from the conversion of sulfur compounds and, in most cases, the final product is sulfate. The acid formed by these bacteria that oxidize sulfides is sulfuric acid. Similarly, bacteria isolated from acid drains, during their metabolic action, generate a decrease in pH. The Thiobacillus genus is relevant among the others for its ability to oxidize sulfur compounds, producing elemental sulfur extracellularly. The energy required to carry out its functions is derived from the oxidation of one or more reduced sulfur compounds including sulfide and thiosulfate. In the study of the...

The study was carried out with isolated strains of acid drainage and consisted of processing of highly mineralized copper sulphides that mainly contained 45.30% pyrite and 13.12% arsenopyrite. Bioleaching was carried out in 500 ml flasks, where 300 ml of 9k medium, 30 ml of bacterial inoculum (10% V / V) of 7.05x107 Cell / ml and various amounts of FeSO4.7H2O were added. The pH was regulated to 1.8 and they were subjected to platform agitation with 150 RPM at ambient temperature of 20 ° C on average. The tests were carried out in three successive stages at different concentrations of ferrous salt. In the first stage, 72.64% copper was obtained with 6 g / l of FeSO4.7H2O in 22 days. In the second stage, 85.6% of copper was achieved in the absence of the ferrous salt. Greater bacterial growth was also achieved with 15 g / l FeSO4.7H2O and 25.62% copper recovery in 24 days of leaching; In ...

Conceptualise the corporate social role, which is being unsuitably developed by some mining companies under the cliché of corporate social responsability (CRS), what may wel fall as philanthropic action. This means that actions taken imply a strong assitance constituent, in which the company asually takes on an active rol, and the beneficiary population a passive role. This form of addressing CRS denotes the absence of non-corporate political role-players, thus reducing the chance of consolidating feedback processes between the corporate social investiment and interest group involved poditively. Inplementation of existing legal framework overflows the field, laws are wrongly interpreted, evaded and finally not applied, consecuently minig industry goes through wrong paths. An interest –conciliating legal framework is an imperative. The legal institutional framework implemented in the e...

Study of the electrochemical behavior of copper allows us to identify and characterize the partially ionic nature of the aqueous solubility of impurities in the mass of ore bodies of metallic materials of copper mineral species and therefrom obtain sequences in the identification and effluent characterization activity hydrometallurgical mineral content with valuable copper. The absorption spectra determninación compounds with metal cores in the range from UV Visible acids sulfur containing base metals means enabling the implementation of the sequential separation of elements and species which are considered deleterious and denote pollution, acting against environmental sustainability.

The challenge of a development model that seeks to harmonize economic, social and environmental issues requires appropriate governance structures to address this complexity, as well as an active participation of citizens in public issues. Participation of civil society in development decisions is crucial to achieving lasting and sustainable solutions. Modern democratic life requires an increasingly active role of the population, community members involvement is required, and citizens should not be allowed to act only when it comes to choosing, and be therefore governed by others, without any possibility of interacting with the ruling people. Now the concept of representative democracy is swifting into a different hue of what is called participatory democracy. In order to move forward to build a participatory democracy, it is necessary to provide citizens with an institutional framework t...

In the extraction and purification of precious metals diverse techniques gravimetric, pyrochemical, hidrochemical, electrochemical are used main to ore sulfides or complex sulfides that contain concealed gold or microscopic gold. The influence of the pyrite presence, copper minerals, that they slow down, they inhibit and /or the transformation metallic gold in solution, they manage to attenuate themselves or to be reduced by means of other necessary treatments that they complement to the cyaniding process, those that can be cycles of roasting, watery leachings with basic acid solutions or under controlled conditions of pressure and temperature, electro oxidation under electrical potential, sequences of ultrasound and by means of the bacterial leaching.

Conceptualise the corporate social role, which is being unsuitably developed by some mining companies under the cliché of corporate social responsability (CRS), what may wel fall as philanthropic action. This means that actions taken imply a strong assitance constituent, in which the company asually takes on an active rol, and the beneficiary population a passive role. This form of addressing CRS denotes the absence of non-corporate political role-players, thus reducing the chance of consolidating feedback processes between the corporate social investiment and interest group involved poditively. Inplementation of existing legal framework overflows the field, laws are wrongly interpreted, evaded and finally not applied, consecuently minig industry goes through wrong paths. An interest –conciliating legal framework is an imperative. The legal institutional framework implemented in the e...

Study of the electrochemical behavior of copper allows us to identify and characterize the partially ionic nature of the aqueous solubility of impurities in the mass of ore bodies of metallic materials of copper mineral species and therefrom obtain sequences in the identification and effluent characterization activity hydrometallurgical mineral content with valuable copper. The absorption spectra determninación compounds with metal cores in the range from UV Visible acids sulfur containing base metals means enabling the implementation of the sequential separation of elements and species which are considered deleterious and denote pollution, acting against environmental sustainability.

El desafío de un modelo de desarrollo que pretenda armonizar lo económico, lo social y lo ambiental requiere de estructuras de gobierno aptas para abordar esta complejidad, a la vez que una activa participación ciudadana en las cuestiones públicas. La participación de la sociedad civil en las decisiones sobre el desarrollo es fundamental para lograr soluciones duraderas y viables. La vida democrática moderna requiere de un rol cada vez más activo de la población, necesitándose la participación de los miembros de la comunidad y no permitiendo que los gobernados solo actúen cuando se trate de elegir y luego, valga la redundancia, son gobernados por otros, sin que exista posibilidad alguna de interactuar con los gobernantes. Ahora, el concepto de democracia representativa va tomando un matiz distinto llamado democracia participativa. Para avanzar en la construcción de una democr...

In the extraction and purification of precious metals diverse techniques gravimetric, pyrochemical, hidrochemical, electrochemical are used main to ore sulfides or complex sulfides that contain concealed gold or microscopic gold. The influence of the pyrite presence, copper minerals, that they slow down, they inhibit and /or the transformation metallic gold in solution, they manage to attenuate themselves or to be reduced by means of other necessary treatments that they complement to the cyaniding process, those that can be cycles of roasting, watery leachings with basic acid solutions or under controlled conditions of pressure and temperature, electro oxidation under electrical potential, sequences of ultrasound and by means of the bacterial leaching.

The mechanisms of conversion to elemental sulfur, sulphites, sulfates and others; they are diverse, leading to the formation of sulfuric acid and therefore, to the acidification of the medium. Based on these characteristics, acidophilic bacteria are considered as sulfur chemolytotrophs, since they obtain their energy from the conversion of sulfur compounds and, in most cases, the final product is sulfate. The acid formed by these bacteria that oxidize sulfides is sulfuric acid. Similarly, bacteria isolated from acid drains, during their metabolic action, generate a decrease in pH. The Thiobacillus genus is relevant among the others for its ability to oxidize sulfur compounds, producing elemental sulfur extracellularly. The energy required to carry out its functions is derived from the oxidation of one or more reduced sulfur compounds including sulfide and thiosulfate. In the study of the...

The study was carried out with isolated strains of acid drainage and consisted of processing of highly mineralized copper sulphides that mainly contained 45.30% pyrite and 13.12% arsenopyrite. Bioleaching was carried out in 500 ml flasks, where 300 ml of 9k medium, 30 ml of bacterial inoculum (10% V / V) of 7.05x107 Cell / ml and various amounts of FeSO4.7H2O were added. The pH was regulated to 1.8 and they were subjected to platform agitation with 150 RPM at ambient temperature of 20 ° C on average. The tests were carried out in three successive stages at different concentrations of ferrous salt. In the first stage, 72.64% copper was obtained with 6 g / l of FeSO4.7H2O in 22 days. In the second stage, 85.6% of copper was achieved in the absence of the ferrous salt. Greater bacterial growth was also achieved with 15 g / l FeSO4.7H2O and 25.62% copper recovery in 24 days of leaching; In ...

The correlactionship of bacterial population and oxidation-reduction potential in the bioleaching of sulfuric minerals by bacterial strain of Aciditiobacilus Ferrooxidans isolated from acid mine effluent was studied. The solubilization of copper and gold release from a mineral with sulphides exceeding 80% was evaluated. The experimental variables were: Pulp density at 1, 2 and 6% (W/V), concentration of ferrous sulfate as part of the 9k medium of 0, 3, 6, 9 and 15 gr/L.; maintaining constant temperature and pH. The tests were carried out in three consecutive stages, starting with inoculum containing 7.05x107 Cell/mL and then the one obtained in each previous stage, observing the variation in the periods of adaptation and growth. In the first stage the maximum bacterial density reached in 24 days was 4.75x107 Cell/mL with 6 g/L of ferrous sulfate. In the second stage a maximum density of ...

The worldwide demand for silver is increasing due to the technological development in different areas, especially for the requirements in the production of renewable energies; therefore, for the treatment of refractory minerals by conventional processes, it is necessary to study mechanisms to identify the viability of their processing and the feasibility of their recovery, ensuring profitability. Gold and silver present in the matrix of sulfide-based ores are not affordably recovered by the conventional method involving leaching in sodium cyanide solution. Therefore, it must be subjected to oxidation pretreatment or conversion of the sulfides to simple compounds that allow recovery of the precious metals. The methods of oxidation of minerals considered refractory are carried out by hydro and pyrometallurgical methods, seeking the dissolution of sulfur, iron, arsenic and other elements pr...

This work describes the isolation and selection of bacterial strains of the genus Pseudomonas in Cetrimide, Acetamide and King B Agar media, from effluents of the leaching process and from the tailings deposit of the gold ore processing plant, Caraveli - Arequipa. Subsequently, the adaptation was made in Modified Mineral Medium (M9M), to different concentrations of sodium cyanide, to evaluate the tolerance and degradation of the CN- radical. The results of sowing in different nutrient media allowed us to observe changes in coloration with a change from clear to intense red in Acetamide Medium and from clear to fluorescent green in King B Agar Medium, revealing the presence of P. pseudoalcaligenes bacteria. Similarly, during the adaptation process of a strain whose initial cell population was 2.0E+06 CFU/mL, in media supplemented with 50, 100, 150, 200 and 250 ppm of Free Cyanide, at the ...

Although it is true that the higher education institutions in engineering since their creation, formulate as a scientific and technological statement as the sole purpose of justifying their existence and validity.

Although it is true that the higher education institutions in engineering since their creation, formulate as a scientific and technological statement as the sole purpose of justifying their existence and validity.

Lleva a cabo la biolixiviación de minerales sulfurados con alto contenido metálico, mediante cepas nativas de Acidithiobacillus ferrooxidans aisladas de efluentes ácido de mina de la región de Huancavelica. Las pruebas se llevaron a cabo en tres etapas de 24 días cada una, primero inoculando la bacteria adaptada en pulpa de mineral y en la segunda y tercera etapa inoculando las usadas en las etapas anteriores, respectivamente. Las principales condiciones fueron: temperatura ambiente (20°C), agitación 150 rpm, pH 2.0 y medio líquido con diversas concentraciones de sulfato ferroso y mineral sulfurado; teniendo como objetivo extraer el cobre y monitorear la dinámica del crecimiento poblacional bacteriano. Mediante el uso de los modelos sigmoideos de Benjamín Gompertz y Pierre François Verhulst, se ha representado paramétrica y gráficamente el crecimiento poblacional de las bact...

Currently, various metallurgical processes are used to obtain and recover metals, and in each one of them inevitable residues are produced, such as the formation of slags, trying to ensure that they have the lowest possible metal content and that their final residues have a later value. for other industrial processes; topic that the present investigation develops. Slag is a phase containing useless substances from a mineral, which are present in any metallurgical process involving smelting. In general, copper slags are Si02 iron silicate oxides, although there are other elements that do not exceed 20% and are therefore not taken into account. With respect to impurities, they play a negative role in its properties such as its electrical and thermal conductivity, its color, its hardness and others; They can be classified into three groups of easy elimination (Zn, Fe, 0 and S), impurities t...

En la actualidad se utilizan diversos procesos metalúrgicos para la obtención y recuperación de metales y en cada uno de ellos se producen residuos inevitables como la formación de escorias, tratándose de que tengan el menor contenido de metal posible y que sus residuos finales tengan un valor posterior para otros procesos industriales; tema que la presente investigación desarrolla. Escoria es una fase que contiene sustancias inútiles de un mineral, que se encuentran presentes en cualquier proceso metalúrgico que involucre fundiciones. Por lo general, las escorias de cobre son óxidos de hierro silicatos Si02, aunque existen otros elementos que no superan el 20% por lo que no se toman en cuenta. Con respecto a las impurezas, éstas ejercen un papel negativo en sus propiedades como su conductividad eléctrica, térmica, su color su dureza y demás; se pueden clasificar en tres gru...