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APLICACION DE ANALISIS DE IMAGENES EN EL CONTROL CINETICO DEL DESARROLLO DE MICROORGANISMOS FILAMENTOSOS

Ingeniería Sanitaria y Ambiental 01/2002; 61:34-41.

ABSTRACT Uno de los problemas más frecuentes en el tratamiento biológico de efluentes líquidos por barros activados puede atribuirse al exceso de microorganismos filamentosos (MFil) los cuales generan bulking. Con el objeto de comprender las causas de la sobreproducción de éstos es necesario estudiar la dinámica de las poblaciones bacterianas involucradas. Los objetivos del presente trabajo fueron: i) estudiar el comportamiento de un cultivo mixto compuesto por un MFil (Sphaerotilus natans ATCC #29329) y uno floculante (Acinetobacter anitratus, cepa floculante E932) frente a variaciones en la velocidad de dilución del reactor mediante el análisis de imágenes y ii) modelar matemáticamente los resultados obtenidos. El medio de cultivo contenía citrato (sustrato limitante) y amonio como únicas fuentes de carbono y nitrógeno respectivamente. Se realizaron experimentos en cultivos puros y mixtos en un quimiostato. La biomasa se determinó en términos de DQO. En el caso de los cultivos mixtos se implementó un método basado en el análisis digital de imágenes (ADI) para evaluar la biomasa correspondiente a cada microorganismo. Los resultados mediante ADI obtenidos demostraron que la composición de un cultivo mixto de S. natans y la cepa E932 es función de la velocidad de dilución; para velocidades de dilución bajas había un predominio de S. natans por sobre la cepa E932. Estas condiciones de operación favorecerían la aparición de bulking filamentoso en plantas de barros activados que tratan efluentes ricos en ácido cítrico como lo son las aguas residuales provenientes de la industria procesadora de vegetales.

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