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Cartas del destierro de Julio Bañados Espinosa: introducción, edición y notas
(Universidad de Chile, 2004)
y morales
que su autor debió soportar. En los dos años y medio que estuvo fuera, sufrió la
ausencia de su familia, la nostalgia de su tierra y gran cantidad de enfermedades
físicas-sorprendentes en un hombre de solo 35 años. En los relatos de...
UNIVERSIDAD DE CHILE FACULTAD DE FILOSOFÍA Y HUMANIDADES DEPARTAMENTO DE LINGÜÍSTICA Cartas del destierro de Julio Bañados Espinosa. Introducción, edición y notas PILAR VIGNEAUX DELPORTE r...
UNIVERSIDAD DE CHILE FACULTAD DE FILOSOFÍA Y HUMANIDADES DEPARTAMENTO DE LINGÜÍSTICA Cartas del destierro de Julio Bañados Espinosa. Introducción, edición y notas PILAR VIGNEAUX DELPORTE r...
Jardines de Campo en Chile Central: Espacios habitacionales y sus significados
(Universidad de Chile, 2019)
que se componen estos espacios habitacionales, las prácticas que ocurren en ellos y en los relatos de sus habitantes. Esto desde la comprensión de los jardines como lugares – espacios significados – que son intensamente habitados y que tienen la...
Biomasa en el desierto de Chile
(Universidad de Chile. Facultad de Ciencias Agronómicas, 2013)
análisis y propuesta de especies nativas o exóticas, con potencial
para la producción de bioenergía en Chile.
La degradación de las tierras áridas, semiáridas y zonas subhúmedas secas por los efectos
de las variaciones climáticas y las actividades humanas...
actividad humana. En términos de la contribución al desarrollo, su importancia para el país se ve reflejada en los aportes a la economía nacional, donde el 20% del PIB corresponde a los sectores primarios de minería, agricultura y pesca. Las exportaciones...
actividad humana. En términos de la contribución al desarrollo, su importancia para el país se ve reflejada en los aportes a la economía nacional, donde el 20% del PIB corresponde a los sectores primarios de minería, agricultura y pesca. Las exportaciones...
Análisis de las medidas de compensación presentadas en la evaluación ambiental : período 2008 a 2015
(Universidad de Chile, 2016)
que pueda
producir una o un conjunto de actividades desarrolladas por el hombre, sobre la vida
humana, la salud, el bienestar del hombre y el medio ambiente y sus ecosistemas. (p.
72)
Guzmán (2012) define al SEIA como:
un procedimiento...
de Impacto Ambiental (en adelante, SEIA) es un instrumento que regula ex ante y de manera preventiva, aquellas actividades determinadas en la ley Nº 19.300 sobre Bases Generales del Medio Ambiente (en adelante, LBGMA), que puedan ocasionar impactos...
de Impacto Ambiental (en adelante, SEIA) es un instrumento que regula ex ante y de manera preventiva, aquellas actividades determinadas en la ley Nº 19.300 sobre Bases Generales del Medio Ambiente (en adelante, LBGMA), que puedan ocasionar impactos...
Factibilidad inmobiliaria de oficinas compartidas para segmentos medios en sectores residenciales en extensión
(Universidad de Chile, 2020)
segmentos o actividades que no requieran un espacio físico definido y centralizado para
su desarrollo, conocidos como “Coworks” o “Cospaces”.
Si bien, estos productos inmobiliarios se adaptan a una necesidad respecto al mercado
laboral y sus nuevas...
de factibilidad de realizar actividades laborales de forma remota. Una de las comunas con mayor población, laboralmente activa y con mayor índice de virtualización de actividades laborales, del sector terciario, corresponde a Puente Alto, dentro...
de factibilidad de realizar actividades laborales de forma remota. Una de las comunas con mayor población, laboralmente activa y con mayor índice de virtualización de actividades laborales, del sector terciario, corresponde a Puente Alto, dentro...
Priorización de inversión pública para proyectos de agua potable rural en la Región Metropolitana de Santiago
(Universidad de Chile, 2015)
internacionales adoptados por el Estado de
Chile en la XII Asamblea Mundial de la Salud de 1959. Esta estableció como prioritario el
abastecimiento público de agua.
El Plan Básico de Saneamiento Rural fue desarrollado con recursos estatales y en conjunto con...
creación de la Oficina de Saneamiento Rural (OSR), dependiente de ex Servicio Nacional de Salud (SNS), quién ejecutó y lideró esta iniciativa. A partir de 1969 se sumaría también a este proceso la Unidad de Agua Potable Rural, del Departamento de Obras...
creación de la Oficina de Saneamiento Rural (OSR), dependiente de ex Servicio Nacional de Salud (SNS), quién ejecutó y lideró esta iniciativa. A partir de 1969 se sumaría también a este proceso la Unidad de Agua Potable Rural, del Departamento de Obras...
Centro educativo Puente Alto. Educación parvularia y básica
(Universidad de Chile, 2015)
enseñanza que imparte:
Sala cuna:
- Área Administrativa: Oficina, Sala
de Amamantamiento y Control de
Salud, Sala Multiusos.
- Área Docente: Salas de Actividades,
Sala de mudas y hábitos higiénicos,
Patio.
- Área de Servicios: Cocina, Bodega,
closet o...
sanitarias y ambientales básicas en los lugares de trabajo. Decreto 594 del Ministerio de Salud - Planta física de los locales educacionales que establecen las exigencias mínimas que deben cumplir los establecimientos reconocidos como cooperadores de la...
sanitarias y ambientales básicas en los lugares de trabajo. Decreto 594 del Ministerio de Salud - Planta física de los locales educacionales que establecen las exigencias mínimas que deben cumplir los establecimientos reconocidos como cooperadores de la...
Calidad y procesos hidrogeoquímicos en el agua de la Región Metropolitana: Estudio del área concesión Smapa
(Universidad de Chile, 2018)
partir de 200 m de profundidad, caracterizado por tener menores valores de C.E. y NO3-. No obstante, esta diferenciación no es observable en toda el área de estudio, indicando que no hay de una separación física continua entre los niveles. Es probable que...
Las legislaciones australiana y chilena en materia indígena : un enfoque para analizar las instituciones estatales en el marco de la protección de los derechos fundamentales
(Universidad de Chile, 2018)
tradicional de éstas con su entorno. Se han privilegiado los proyectos de desarrollo y las actividades extractivistas de recursos naturales, afectando territorios indígenas. La “modernización legislativa” en leyes sectoriales durante la dictadura militar...
Tratamiento integral de drenajes ácidos de mina mediante metodologías de adsorción química
(Universidad de Chile, 2019)
corresponden a “drenajes ácidos de mina” (DAM), como también soluciones residuales de los procesos minero-metalúrgicos. Las primeras corresponden a aguas naturales generadas en torno a los yacimientos mineros mediante oxidación química y/o biológica de...
In this Doctoral Thesis, the integral treatment of acid mine water was studied using three adsorbents synthesized in this work. In the mining operations, different types of acidic aqueous solutions are usually found, some of them corresponding to "acid mine drainage" (AMD), as well as residual solutions of the mining-metallurgical processes. The first one corresponds to natural waters generated around mining deposits by chemical and/or biological oxidation of polysulfurized deposits. The other type of mine acid water corresponds to wastewater generated in leaching, solvent extraction, flotation, and so on. All these solutions contain a high load of heavy metals, sulfate ions and other anions. The three adsorbents synthesized and characterized in this study to be used in the treatment of mine waters, correspond to: polymeric microcapsules containing non-specific extractants (MCEx), nanostructured calcium silicates (NanoCSH) and magnetized manganese dioxide (mag-MnO2). The synthesis was studied for each one of them, they were characterized chemically and physically, and they were applied in the waters to be treated with different specific objectives. The microcapsules were used to recover copper and zinc, the NanoCSH were used to remove high concentrations of heavy metals and anions such as phosphates and sulphates and suspended fine solid material. Finally, mag-MnO2 was used to eliminate low concentrations at trace level of lead and can also be used to remove cadmium and arsenic contents. a) Regarding the use of polymeric microcapsules containing extractants, these were prepared by two simple and low-cost methods: one physical-mechanical (evaporation of the solvent) and one chemical (polymerization with extractant in situ). These MCs, once prepared, contained retained in their interior, extractants of commercial name PC-88A (a weak acid of the alkyl phosphonic type) and LIX-860 N-IC (a beta-hydroxyoxime), capable of recovering zinc and xi copper, respectively. These microcapsules were characterized by different methodologies and were applied in reactors in continuous columns. The columns were packed with the synthesized microcapsules and the aqueous solutions to be treated were circulated by peristaltic pumps. The effect on the copper and zinc removal was studied, as well as the concentration of the metal in the aqueous solution, the height of the column used and the flow rate of the feed solution in the column. On average, high adsorption yields were obtained, of the order of 90% in both cases. Different models were used to describe the adsorption curves in columns for both microencapsulated extractants. Among these we have the models of Thomas, Wang and the Dose-Response, the latter model being the one that best adjusted the results achieved. b) Regarding the use of nanostructured calcium silicates, three different adsorbents were synthesized. One of them corresponds to the unmodified calcium silicate, a nanostructured calcium silicate modified with magnesium and, finally, a nanostructured calcium silicate modified with aluminum. The syntheses in all cases turned out to be simple and reproducible with yields higher than 80%. All of them were synthesized by the reaction of liquid sodium silicate with calcium hydroxide disintegrated in HCl and under intense condition of mechanical agitation, generating very quickly a granular precipitate easy to separate from the reaction medium by filtration and decantation. The proposed structural modifications were made by replacing some calcium atoms of the silicate with magnesium and aluminum atoms, using in the respective synthesis Mg(OH)2, PAC (aluminum hydroxychloride) and NaAlO2. The modification with magnesium was designed with the purpose of improving the removal of phosphate ions. The modification with aluminum was made with the aim of favoring the removal of sulfate ions. These adsorbents were also chemically and physically characterized using the SEM, DRX, N2 intrusion porosimetry, FT-IR methodologies and chemical stability studies. The adsorption experiments were carried out in batch reactors. In all cases high removals of heavy metals and anionic species were achieved. Adsorption xii equilibrium experiments were also carried out, the results of which were explained by the Langmuir, Freundlich, Langmuir-Freundlich and Redlich-Peterson models. Complementarily, adsorption kinetics experiments of some of the studied pollutants were also carried out. The experimental results were tried to explain by means of pseudo-first-order and pseudo-second-order models, the latter being in general the one that best explained the experimental results obtained. c) Finally, and as a final stage of the proposed process, adsorption studies were carried out on some of the most toxic pollutants present in a lower concentration in the mine waters, by means of the magnetized manganese dioxide adsorbent. The purpose of granting magnetic properties to the MnO2 adsorbent was to facilitate the separation, once the adsorption was complete, of the adsorbent charged in the pollutants removed from the resulting aqueous phase, by means of the use of a conventional neodymium magnet. In this way cumbersome stages of sedimentation or filtration are avoided. The synthesis of mag-MnO2 was carried out by means of an oxidative precipitation process using as precursors MnCl2 and KMnO4, adding a certain proportion of magnetite (Fe3O4) to the reaction medium. The process was carried out in a basic medium, reaching synthesis yields close to 100%. This adsorbent was characterized chemically and physically using similar methodologies for the previous adsorbents. However, magnetism analysis by VSM (Vibrating Sample Magnetometer) was also included. In particular, the removal of low concentrations of lead ions was studied, reaching high yields of Pb (II) adsorption, for aqueous solutions whose pHs were higher than pHZC. In this part of the study we also performed equilibrium and adsorption kinetics experiments, whose results were explained by the hybrid model of Langmuir-Freundlich and the kinetic model of pseudo-second-order, respectively. Finally, in the last chapter, based on the experimental results obtained in this study and results achieved in other stages of the Fondecyt research project that funded this Thesis, a comprehensive xiii mine water treatment system is proposed that includes the indicated adsorbents together with other primary and tertiary treatments, thus configuring a complete mine water treatment plant...
In this Doctoral Thesis, the integral treatment of acid mine water was studied using three adsorbents synthesized in this work. In the mining operations, different types of acidic aqueous solutions are usually found, some of them corresponding to "acid mine drainage" (AMD), as well as residual solutions of the mining-metallurgical processes. The first one corresponds to natural waters generated around mining deposits by chemical and/or biological oxidation of polysulfurized deposits. The other type of mine acid water corresponds to wastewater generated in leaching, solvent extraction, flotation, and so on. All these solutions contain a high load of heavy metals, sulfate ions and other anions. The three adsorbents synthesized and characterized in this study to be used in the treatment of mine waters, correspond to: polymeric microcapsules containing non-specific extractants (MCEx), nanostructured calcium silicates (NanoCSH) and magnetized manganese dioxide (mag-MnO2). The synthesis was studied for each one of them, they were characterized chemically and physically, and they were applied in the waters to be treated with different specific objectives. The microcapsules were used to recover copper and zinc, the NanoCSH were used to remove high concentrations of heavy metals and anions such as phosphates and sulphates and suspended fine solid material. Finally, mag-MnO2 was used to eliminate low concentrations at trace level of lead and can also be used to remove cadmium and arsenic contents. a) Regarding the use of polymeric microcapsules containing extractants, these were prepared by two simple and low-cost methods: one physical-mechanical (evaporation of the solvent) and one chemical (polymerization with extractant in situ). These MCs, once prepared, contained retained in their interior, extractants of commercial name PC-88A (a weak acid of the alkyl phosphonic type) and LIX-860 N-IC (a beta-hydroxyoxime), capable of recovering zinc and xi copper, respectively. These microcapsules were characterized by different methodologies and were applied in reactors in continuous columns. The columns were packed with the synthesized microcapsules and the aqueous solutions to be treated were circulated by peristaltic pumps. The effect on the copper and zinc removal was studied, as well as the concentration of the metal in the aqueous solution, the height of the column used and the flow rate of the feed solution in the column. On average, high adsorption yields were obtained, of the order of 90% in both cases. Different models were used to describe the adsorption curves in columns for both microencapsulated extractants. Among these we have the models of Thomas, Wang and the Dose-Response, the latter model being the one that best adjusted the results achieved. b) Regarding the use of nanostructured calcium silicates, three different adsorbents were synthesized. One of them corresponds to the unmodified calcium silicate, a nanostructured calcium silicate modified with magnesium and, finally, a nanostructured calcium silicate modified with aluminum. The syntheses in all cases turned out to be simple and reproducible with yields higher than 80%. All of them were synthesized by the reaction of liquid sodium silicate with calcium hydroxide disintegrated in HCl and under intense condition of mechanical agitation, generating very quickly a granular precipitate easy to separate from the reaction medium by filtration and decantation. The proposed structural modifications were made by replacing some calcium atoms of the silicate with magnesium and aluminum atoms, using in the respective synthesis Mg(OH)2, PAC (aluminum hydroxychloride) and NaAlO2. The modification with magnesium was designed with the purpose of improving the removal of phosphate ions. The modification with aluminum was made with the aim of favoring the removal of sulfate ions. These adsorbents were also chemically and physically characterized using the SEM, DRX, N2 intrusion porosimetry, FT-IR methodologies and chemical stability studies. The adsorption experiments were carried out in batch reactors. In all cases high removals of heavy metals and anionic species were achieved. Adsorption xii equilibrium experiments were also carried out, the results of which were explained by the Langmuir, Freundlich, Langmuir-Freundlich and Redlich-Peterson models. Complementarily, adsorption kinetics experiments of some of the studied pollutants were also carried out. The experimental results were tried to explain by means of pseudo-first-order and pseudo-second-order models, the latter being in general the one that best explained the experimental results obtained. c) Finally, and as a final stage of the proposed process, adsorption studies were carried out on some of the most toxic pollutants present in a lower concentration in the mine waters, by means of the magnetized manganese dioxide adsorbent. The purpose of granting magnetic properties to the MnO2 adsorbent was to facilitate the separation, once the adsorption was complete, of the adsorbent charged in the pollutants removed from the resulting aqueous phase, by means of the use of a conventional neodymium magnet. In this way cumbersome stages of sedimentation or filtration are avoided. The synthesis of mag-MnO2 was carried out by means of an oxidative precipitation process using as precursors MnCl2 and KMnO4, adding a certain proportion of magnetite (Fe3O4) to the reaction medium. The process was carried out in a basic medium, reaching synthesis yields close to 100%. This adsorbent was characterized chemically and physically using similar methodologies for the previous adsorbents. However, magnetism analysis by VSM (Vibrating Sample Magnetometer) was also included. In particular, the removal of low concentrations of lead ions was studied, reaching high yields of Pb (II) adsorption, for aqueous solutions whose pHs were higher than pHZC. In this part of the study we also performed equilibrium and adsorption kinetics experiments, whose results were explained by the hybrid model of Langmuir-Freundlich and the kinetic model of pseudo-second-order, respectively. Finally, in the last chapter, based on the experimental results obtained in this study and results achieved in other stages of the Fondecyt research project that funded this Thesis, a comprehensive xiii mine water treatment system is proposed that includes the indicated adsorbents together with other primary and tertiary treatments, thus configuring a complete mine water treatment plant...