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Utilización De Modelos De Calidad En Redes De Distribución De Agua Potable Para Evaluar El Riesgo Por Introducción De Sustancias Tóxicas

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Utilización De Modelos De Calidad En Redes De Distribución De Agua Potable Para Evaluar El Riesgo Por Introducción De Sustancias Tóxicas UTILIZACIÓN DE MODELOS DE CALIDAD EN REDES DE DISTRIBUCIÓN DE AGUA POTABLE PARA EVALUAR EL RIESGO POR INTRODUCCIÓN DE SUSTANCIAS TÓXICAS Julián Alberto Gallego Urrea Asesor: Juan Guillermo Saldarriaga Valderrama Trabajo presentado para obtener el título de Magíster en Ingeniería Civil. UNIVERSIDAD DE LOS ANDES FACULTAD DE INGENIERIA Departamento de Ingeniería Civil y Ambiental Bogotá D.C., Agosto de 2003 Utilización de los modelos de calidad en redes de distribución de agua MIC-2003-II-43 potable para evaluar el riesgo por introducción de sustancias tóxicas. Tabla de contenido 1. Introducción.................................................................................................................... 1 2. Objetivos......................................................................................................................... 3 2.1. Objetivo General..................................................................................................... 3 2.2. Objetivos específicos.............................................................................................. 3 3. Marco teórico.................................................................................................................. 4 3.1. Conceptos de toxicidad y evaluación de riesgos .................................................... 5 3.1.1. Dosificación efectiva ...................................................................................... 5 3.1.2. Ingestión diaria aceptable ............................................................................... 7 3.1.3. Dosis de Referencia (DdR). Adaptado de Universidad de Arizona, 2001. .... 7 3.1.4. Cálculo de la dosis suministrada .................................................................... 9 3.2. Contaminantes químicos...................................................................................... 11 3.2.1. Características especiales de incidentes químicos........................................ 12 3.3. Contaminantes biológicos .................................................................................... 13 3.4. Modelación de sustancias tóxicas en agua ........................................................... 14 3.4.1. Evolución de las técnicas de modelación ..................................................... 17 3.4.2. Partición sólido-líquido de los contaminantes tóxicos. ................................18 3.4.3. Hidrólisis de pesticidas Órgano-Fosforados................................................. 19 3.5. Modelación de la calidad del agua en EPANET .................................................. 20 3.5.1. Algoritmo de rastreo de segmentos. ............................................................. 21 3.5.2. Transporte advectivo en tuberías.................................................................. 22 3.5.3. Mezcla en los nodos. .................................................................................... 25 3.5.4. Reacciones en calidad del agua. ................................................................... 26 3.5.5. Fuentes de calidad del agua.......................................................................... 32 3.5.6. Modelos de mezcla en tanques. .................................................................... 32 3.5.7. Parámetros utilizados por EPANET............................................................. 34 4. Metodología..................................................................................................................36 4.1. Recopilación de información................................................................................ 36 4.1.1. Información en Internet ................................................................................ 36 4.1.2. Búsqueda bibliográfica................................................................................. 39 4.1.3. Estudio del caso colombiano ........................................................................ 39 4.2. Análisis de información........................................................................................ 39 4.3. Modelación de tóxicos en redes de distribución de agua potable......................... 40 4.4. Análisis cualitativo de riesgo................................................................................ 40 5. Recopilación y análisis de información........................................................................ 41 5.1. Contaminantes Químicos...................................................................................... 43 5.1.1. Pesticidas y químicos relacionados .............................................................. 44 5.2. Microorganismos.................................................................................................. 46 5.3. Características físico químicas de los contaminantes tóxicos de interés.............. 47 5.4. Métodos actuales para el monitoreo de contaminantes tóxicos en los sistemas de distribución de agua potable............................................................................................. 48 5.5. Análisis de sitios vulnerables al vertimiento de tóxicos en los sistemas de distribución de agua potable............................................................................................. 49 Universidad de los Andes – Departamento de Ingeniería Civil y Ambiental III Magíster en Ingeniería Civil Utilización de los modelos de calidad en redes de distribución de agua MIC-2003-II-43 potable para evaluar el riesgo por introducción de sustancias tóxicas. 5.6. Evolución del uso de plaguicidas en Colombia (Idrovo, 2000) ........................... 51 6. Modelación de tóxicos en los módulos de calidad del agua de los programas computacionales ...................................................................................................................55 6.1. Análisis de las variables utilizadas en la modelación de calidad del agua en redes de distribución ..................................................................................................................56 6.1.1. Propiedades de la sustancia .......................................................................... 56 6.1.2. Patrones hidráulicos y de calidad en el tiempo............................................. 58 6.1.3. Fuentes de contaminantes:............................................................................ 59 6.1.4. Resultados obtenidos de la modelación:....................................................... 59 6.2. Programa computacional para evaluar la introducción de sustancias tóxicas en redes de distribución......................................................................................................... 59 6.2.1. Organización del archivo de entrada (*.inp). ............................................... 61 6.2.2. Determinar la masa y hora de entrada de un contaminante.......................... 61 6.2.3. Encontrar la concentración de contaminante y la hora de detección en un nodo determinado. ........................................................................................................ 62 6.2.4. Graficar la concentración relativa en los nodos y el tiempo de llegada para una hora determinada.................................................................................................... 63 6.2.5. Graficar la concentración relativa y el tiempo de llegada para un nodo determinado. ................................................................................................................. 64 7. Análisis de riesgo ......................................................................................................... 66 8. Análisis de resultados ................................................................................................... 69 9. Conclusiones.................................................................................................................76 9.1. Herramientas computacionales para el análisis de riesgo en redes de distribución. 76 9.2. Modelación de la calidad del agua. ...................................................................... 76 9.3. Sustancias tóxicas................................................................................................. 77 9.4. Vulnerabilidad de los sistemas de distribución. ................................................... 77 9.5. Instrumentos de detección y monitoreo................................................................ 78 9.6. Evaluación del riesgo............................................................................................ 78 9.7. Análisis de la red matriz de Medellín................................................................... 79 9.8. Contaminantes biológicos. ................................................................................... 79 10. Recomendaciones ..................................................................................................... 81 10.1. Información Físico-Química............................................................................. 81 10.2. Futuro del análisis de riesgo. ............................................................................ 81 10.3. Tecnologías de detección.................................................................................. 81 10.4. Modelación de la calidad del agua en redes de distribución de agua potable. 82 11. Bibliografía...............................................................................................................83 11.1. Bibliografía Principal ......................................................................................
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