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Modelamiento de la dinámica microbiana a cambios multivariados de un reactor de lodos activados
(Universidad de Chile, 2007)
En el contexto del Desarrollo Sustentable, Chile ha comenzado acciones dirigidas a los recursos hídricos enfocadas en un mejor aprovechamiento y tratamiento de las aguas residuales para su reuso en agricultura y otras actividades.
La Tecnología de...
Determinación de triclosán en tejido vegetal y evaluación de su fracción bioaccesible
(Universidad de Chile, 2016)
En vista de la toxicidad descrita para triclosán, su uso en diversos productos de higiene per-sonal y los hallazgos descritos en la literatura sobre la presencia de triclosán en aguas resi-duales, las cuales se usan para regadío en zonas agrícolas...
In view of the toxicity of triclosan, the use of this compound in various personal hygiene prod-ucts and information published in other countries about the presence of triclosan in wastewater, which are used for irrigation in agricultural areas, was proposed for this study to evaluate the bioaccessibility of triclosan in two vegetables commonly consumed in Chile. Lettuce (Lactuca sativa L.) was chosen as a model vegetable whose edible portion is not in contact with the soil, and radish (Raphanus sativus L.) whose edible portion is developed in direct contact with the soil. To carry out this goal, both species were grown in a hydroponic medium and subsequently treated with a solution containing triclosan. The bioaccessibility of triclosan in plant tissue was estimated using an in vitro test based on the physiology (PBET). For the analysis of triclosan it was implemented and validated a method by gas chromatography with electron micro capture detector (GC-μECD) to determine the pseudototal concentration in the vegetal matrix and the concentration in the gastrointestinal fluids substitutes. The results indicate that the triclosan can be extracted efficiently from plant matrices using a solvent consisting of water: acetonitrile 1:1 and metaphosphoric acid 2% (w/w) with subsequent concentration and cleaning in columns of solid phase extraction (C-18). The optimized method complies with the main validation parameters, among them are highlighted a selective and sensitive method with limits of detection and quantification of the technique of 0.32 and 0.97 μg/L, respectively, with a coefficient of variation of 10.7% in reproducibility and with a 88.1% recovery. Triclosan can be absorbed by lettuce and radish grown hydroponically. In the case of lettuce, triclosan can be translocated to the aerial part significantly, while for radish, compound accu-mulates in the storage organ of the plant. Through a PBET test it shows that a fraction of triclo-san is bioaccessible in the edible part of lettuce and radish. The bioaccessible concentrations in lettuce leaves varied in the range 0.14-0.45 μg/g, which represents a variation in the bioac-cessibility in the range 5.6-16%. In the case of radish, the ranges were 0.15-0.34 μg/g and 7.9-36.6%, respectively...
In view of the toxicity of triclosan, the use of this compound in various personal hygiene prod-ucts and information published in other countries about the presence of triclosan in wastewater, which are used for irrigation in agricultural areas, was proposed for this study to evaluate the bioaccessibility of triclosan in two vegetables commonly consumed in Chile. Lettuce (Lactuca sativa L.) was chosen as a model vegetable whose edible portion is not in contact with the soil, and radish (Raphanus sativus L.) whose edible portion is developed in direct contact with the soil. To carry out this goal, both species were grown in a hydroponic medium and subsequently treated with a solution containing triclosan. The bioaccessibility of triclosan in plant tissue was estimated using an in vitro test based on the physiology (PBET). For the analysis of triclosan it was implemented and validated a method by gas chromatography with electron micro capture detector (GC-μECD) to determine the pseudototal concentration in the vegetal matrix and the concentration in the gastrointestinal fluids substitutes. The results indicate that the triclosan can be extracted efficiently from plant matrices using a solvent consisting of water: acetonitrile 1:1 and metaphosphoric acid 2% (w/w) with subsequent concentration and cleaning in columns of solid phase extraction (C-18). The optimized method complies with the main validation parameters, among them are highlighted a selective and sensitive method with limits of detection and quantification of the technique of 0.32 and 0.97 μg/L, respectively, with a coefficient of variation of 10.7% in reproducibility and with a 88.1% recovery. Triclosan can be absorbed by lettuce and radish grown hydroponically. In the case of lettuce, triclosan can be translocated to the aerial part significantly, while for radish, compound accu-mulates in the storage organ of the plant. Through a PBET test it shows that a fraction of triclo-san is bioaccessible in the edible part of lettuce and radish. The bioaccessible concentrations in lettuce leaves varied in the range 0.14-0.45 μg/g, which represents a variation in the bioac-cessibility in the range 5.6-16%. In the case of radish, the ranges were 0.15-0.34 μg/g and 7.9-36.6%, respectively...
BIBLIOGRAFÍA SOBRE EL RÍO MAPOCHO
(UNIVERSIDAD DE CHILE, FACULTAD DE ARQUITECTURA Y URBANISMO, Departamento de Urbanismo., 2007-11)
REALIZACIONES RECIENTES EN TORNO AL
RÍO MAPOCHO. 5.1. Plantas de tratamiento y medidas para el tratamiento de las aguas contaminadas. 5.2.
Proyecto Costanera Norte. 5.3. Transformación del río Mapocho: Proyecto sistema de exclusas. 5.4. Proyectos
Bicentenario...
Saneamiento Hídrico de la cuenca Maipo-Mapocho. Para el Gran Santiago, este plan incluye la construcción y posterior operación de colectores interceptores y tres plantas de tratamiento de aguas servidas. Los colectores interceptores permiten eliminar las...
Saneamiento Hídrico de la cuenca Maipo-Mapocho. Para el Gran Santiago, este plan incluye la construcción y posterior operación de colectores interceptores y tres plantas de tratamiento de aguas servidas. Los colectores interceptores permiten eliminar las...
Diseño del ánodo de una celda de combustible microbiológica para la producción de energía a partir de aguas residuales
(Universidad de Chile, 2017)
El tratamiento de aguas residuales es uno de los procesos más importantes que se deben realizar para cuidar el medio ambiente. El principal objetivo de este tratamiento es permitir la disposición de estos efluentes, tanto domésticos como...
Propuesta y evaluación de estrategias de minimización del uso de agua en la producción de jugos sin aditivos
(Universidad de Chile, 2016)
El agua es un recurso natural fundamental para la vida y la salud de las personas, y a lo largo del tiempo se ha vuelto un elemento indispensable en la producción industrial y generación de energía. Se espera que la demanda de agua dulce aumente en...
Metodología de diseño de hornos para tratamiento térmico de distensionado de grandes piezas ferrosas de minería
(Universidad de Chile, 2020)
hornos para tratamiento térmico de distensionado según el código ASME VIII, UW-40. Los objetivos específicos son: i. Desarrollar una metodología para el diseño básico de la envolvente, ii. Establecer los criterios y tipos de diseño para el sistema de...
Evaluación de una planta piloto de remoción de arsénico por adsorción mediante un medio agaroso
(Universidad de Chile, 2013)
La presencia de arsénico en fuentes de agua para el consumo humano en el norte de Chile obliga a implementar sistemas de tratamiento, lo cual en algunas localidades se ve limitado por factores económicos, técnicos y culturales. De este modo se hace...
Valoración de Empresa Aguas Andinas S.A.
(Universidad de Chile, 2019-01)
internacional OHSAS 18.001.
• Año 2013: Comienza a operar la Planta de Tratamiento de Aguas Servidas Mapocho, cuyo
objetivo es sanear el 100% de las aguas residuales de la Región Metropolitana. Se da inicio,
además, al Proyecto Ariete con el fin de incorporar...
Grupo Agbar (50%) y Suez (50%). • Año 2000: Se construye la Planta de Tratamiento de Aguas Servidas El Trebal. Es adquirido el 100% de Aguas Cordillera y el 50% de Aguas Manquehue. • Año 2001: La compañía cambia de nombre a Aguas Andinas S...
Grupo Agbar (50%) y Suez (50%). • Año 2000: Se construye la Planta de Tratamiento de Aguas Servidas El Trebal. Es adquirido el 100% de Aguas Cordillera y el 50% de Aguas Manquehue. • Año 2001: La compañía cambia de nombre a Aguas Andinas S...
Diagnóstico para la mejora de la evaluación de impacto por olor en el marco del sistema de evaluación de impacto ambiental (SEIA)
(Universidad de Chile, 2019-01)
y predicción del impacto y las medidas mitigadoras y/o de control. En ellos se encontró bastante disparidad en las evaluaciones. El sector de Plantas elaboradoras de harina y aceite de pescado junto con plantas de celulosas fueron los sectores...
In this Seminar a series was established actions and recommendations to improve the evaluation of impact for smell, in the frame of the System of Evaluation of Environmental Impact. To reach this aim three concrete lines of action followed: In the first place, 20 projects entered and approved in the SEIA were selected from five potential industrial sectors that generate odor: (1) Sewage Treatment Plants, (2) Sanitary Landfills, (3) Fishmeal and fish oil processing plants. , (4) Celulosas and (5) Porcine plants. They reviewed the environmental assessment process, and evaluated the application of criteria with reference to odors, in terms of project description, area of influence, evaluation and prediction of impact and mitigating and / or control measures. They found quite disparity in the evaluations. The fishmeal and fish oil processing plants sector together with the cellulosic plants were the industrial sectors with the lowest evaluation criteria in reference to odors. However, the sectors associated with PTAS and Sanitary Landfill used odor evaluation methodologies. international standards that are closer to the development of an optimal odor evaluation. The identification of these methods and procedures based on the diagnosis of the environmental assessment process contributed to the later consideration of the final proposal of this Seminar. Secondly, the international experience was evaluated, identifying the criteria used for the evaluation of scents of two international guides. In this review, significant evaluative criteria were identified to be considered in an odor evaluation, such as, for example, the considerations that must be taken according to the type of project under evaluation for the choice of methodology. For new projects the most optimal tools refer to predictive or quantitative methods, such as modeling, the most important thing in these cases is the use of reliable input data in the model. For existing projects it was estimated that the use of observational / empirical tools could yield accurate results, however, the combination of some quantitative method could support the results of this. On the other hand, the applicable international regulations of the reference countries mentioned in the RegSEIA were evaluated. It was noted that there are various regulatory approaches that can be used when evaluating odors, such as the use of individual odoriferous substances or odor itself, which include variables to compare such as, land use, type of industrial activity, that refer to a greater regulatory specificity approaching more to the preventive approach that should be considered when evaluating an environmental impact. Finally, the information collected from six companies dedicated to the evaluation of odor was analyzed, through workshops, interviews and field visits. In this way, the deficiencies and positive aspects that are generated in the odor assessments that are generated today at the national level were identified. In this sense, it was demonstrated that the lack of legal tools has produced gaps and uncertainties with respect to the appropriate methodologies that should be used to evaluate odors. Finally, there was analyzed the information obtained of six companies dedicated to the evaluation of smell, across workshops, interviews and visit to area. Hereby there were identified the deficiencies and positive aspects that are generated in the evaluations of smell that are generated nowadays in the national plane. The diagnosis, evaluation and analysis of these three lines of action, they determined a more complete vision as for the tools of evaluation. From it, one proposed a series of actions and recommendations to realize an ideal evaluation of smell in potentially generating projects of smell that enter to the System of Evaluation of Environmental Impact. This offer realized on the basis of the minimal contents that it must have a Study of Environmental Impact (EIA): i) Description of the project, ii) Area of influence, ii) Prediction and Evaluation of the impact and iv) Measures mitigating and / or of control....
In this Seminar a series was established actions and recommendations to improve the evaluation of impact for smell, in the frame of the System of Evaluation of Environmental Impact. To reach this aim three concrete lines of action followed: In the first place, 20 projects entered and approved in the SEIA were selected from five potential industrial sectors that generate odor: (1) Sewage Treatment Plants, (2) Sanitary Landfills, (3) Fishmeal and fish oil processing plants. , (4) Celulosas and (5) Porcine plants. They reviewed the environmental assessment process, and evaluated the application of criteria with reference to odors, in terms of project description, area of influence, evaluation and prediction of impact and mitigating and / or control measures. They found quite disparity in the evaluations. The fishmeal and fish oil processing plants sector together with the cellulosic plants were the industrial sectors with the lowest evaluation criteria in reference to odors. However, the sectors associated with PTAS and Sanitary Landfill used odor evaluation methodologies. international standards that are closer to the development of an optimal odor evaluation. The identification of these methods and procedures based on the diagnosis of the environmental assessment process contributed to the later consideration of the final proposal of this Seminar. Secondly, the international experience was evaluated, identifying the criteria used for the evaluation of scents of two international guides. In this review, significant evaluative criteria were identified to be considered in an odor evaluation, such as, for example, the considerations that must be taken according to the type of project under evaluation for the choice of methodology. For new projects the most optimal tools refer to predictive or quantitative methods, such as modeling, the most important thing in these cases is the use of reliable input data in the model. For existing projects it was estimated that the use of observational / empirical tools could yield accurate results, however, the combination of some quantitative method could support the results of this. On the other hand, the applicable international regulations of the reference countries mentioned in the RegSEIA were evaluated. It was noted that there are various regulatory approaches that can be used when evaluating odors, such as the use of individual odoriferous substances or odor itself, which include variables to compare such as, land use, type of industrial activity, that refer to a greater regulatory specificity approaching more to the preventive approach that should be considered when evaluating an environmental impact. Finally, the information collected from six companies dedicated to the evaluation of odor was analyzed, through workshops, interviews and field visits. In this way, the deficiencies and positive aspects that are generated in the odor assessments that are generated today at the national level were identified. In this sense, it was demonstrated that the lack of legal tools has produced gaps and uncertainties with respect to the appropriate methodologies that should be used to evaluate odors. Finally, there was analyzed the information obtained of six companies dedicated to the evaluation of smell, across workshops, interviews and visit to area. Hereby there were identified the deficiencies and positive aspects that are generated in the evaluations of smell that are generated nowadays in the national plane. The diagnosis, evaluation and analysis of these three lines of action, they determined a more complete vision as for the tools of evaluation. From it, one proposed a series of actions and recommendations to realize an ideal evaluation of smell in potentially generating projects of smell that enter to the System of Evaluation of Environmental Impact. This offer realized on the basis of the minimal contents that it must have a Study of Environmental Impact (EIA): i) Description of the project, ii) Area of influence, ii) Prediction and Evaluation of the impact and iv) Measures mitigating and / or of control....
Microextracción de fármacos antiinflamatorios no esteroidales desde matrices acuosas usando polímero de impresión molecular inmovilizado en un sistema de disco rotatorio
(Universidad de Chile, 2014)
Los llamados contaminantes emergentes, están presentes en un variado rango de productos de la vida cotidiana, como los productos farmacéuticos que son liberados de manera indiscriminada a las plantas de tratamiento de aguas, donde al no ser...
The so called emerging contaminants are present in a wide range of daily life products such as drugs that are haphazardly released into water treatment plants where, as they are not completely removed, they tend to remain in the aqueous phase and consequently are found in surface waters. The concern lies in that they can transform into products that are more toxic and more dangerous than the original contaminants. Non-steroidal anti-inflammatory drugs (NSAIDs) are a type of drugs that have been frequently detected in the environment and are not regulated by law. For this reason, an analytical method was developed to determine the concentration of the most commonly used NSAIDs in aqueous samples, using the rotating-disk sorptive microextraction technique (RDSE). The extraction device, made of Teflon, contains a cavity in which it can immobilize a molecularly imprinted polymer (MIP) as a selective sorbent for extracting analytes, which are subsequently quantified using the gas chromatography-mass spectrometry (GC-MS) method once the extracts from RDSE were subject to a derivatization process. The optimal condition for extraction of the mefenamic acid and diclofenac NSAIDs were the following: sample volume of 50 mL, 25 mg of MIP, 3000 rpm agitation, extraction time 60 min, pH2 and desorption with 10 mL of methanol during 5 minutes. For the drugs under study, it was shown that the sorbent phase of MIP recovered on average three times more than the same phase with no imprinted polymer (NIP), evidencing the effect of the cavities of the imprinted molecule. The proposed methodology was validated using a potable water matrix The method achieved NSAIDs detection limits between 0.060 to 0.223 ugL-1 with recoveries between 99-100% ± 5-6%. The application (of this method) to waste water samples obtained from a water treatment plant in Santiago showed NSAIDs concentrations of 1.8 to 4.3 μgL-1 in the influent stream and 1.3 to 2.8 μgL-1 in the effluent stream...
The so called emerging contaminants are present in a wide range of daily life products such as drugs that are haphazardly released into water treatment plants where, as they are not completely removed, they tend to remain in the aqueous phase and consequently are found in surface waters. The concern lies in that they can transform into products that are more toxic and more dangerous than the original contaminants. Non-steroidal anti-inflammatory drugs (NSAIDs) are a type of drugs that have been frequently detected in the environment and are not regulated by law. For this reason, an analytical method was developed to determine the concentration of the most commonly used NSAIDs in aqueous samples, using the rotating-disk sorptive microextraction technique (RDSE). The extraction device, made of Teflon, contains a cavity in which it can immobilize a molecularly imprinted polymer (MIP) as a selective sorbent for extracting analytes, which are subsequently quantified using the gas chromatography-mass spectrometry (GC-MS) method once the extracts from RDSE were subject to a derivatization process. The optimal condition for extraction of the mefenamic acid and diclofenac NSAIDs were the following: sample volume of 50 mL, 25 mg of MIP, 3000 rpm agitation, extraction time 60 min, pH2 and desorption with 10 mL of methanol during 5 minutes. For the drugs under study, it was shown that the sorbent phase of MIP recovered on average three times more than the same phase with no imprinted polymer (NIP), evidencing the effect of the cavities of the imprinted molecule. The proposed methodology was validated using a potable water matrix The method achieved NSAIDs detection limits between 0.060 to 0.223 ugL-1 with recoveries between 99-100% ± 5-6%. The application (of this method) to waste water samples obtained from a water treatment plant in Santiago showed NSAIDs concentrations of 1.8 to 4.3 μgL-1 in the influent stream and 1.3 to 2.8 μgL-1 in the effluent stream...