Problemas relacionados a cenizas de biomasas con alto contenido de sales alcalinas y su mitigación
evaluación experimental
Palabras clave:
Biomasa, Ceniza, Calderas, Corrosión, FusiónResumen
La biomasa está considerada como una fuente renovable de energía y está jugando un papel muy importante en la búsqueda de nuevas fuentes de energía. La reciente tendencia a consumir cultivos energéticos del tipo herbáceo ha causado problemas en los sistemas industriales, debido principalmente a la composición de su ceniza rica en Potasio, Sodio, Cloro y Fósforo. Dichas sales forman eutécticos de bajo punto de fusión formando zonas líquidas que aglomeran partículas sólidas (fouling) o fundiendo por completo (slagging). Este trabajo resume las investigaciones de los últimos años en este tema, discutiendo la importancia del análisis de laboratorio. Los métodos para evitar dichos problemas en las calderas son evaluados, principalmente el baño del combustible con agua (leaching) y el agregado de sales estables a la ceniza en el quemador. Tomando el caso de la Caña Común (Arundo Donax) como un potencial combustible de alto rendimiento por hectárea, se presentan resultados de la evaluación de su ceniza y se estima su potencial de daño en calderas, como producto de nuestra investigación experimental.Se investiga en el laboratorio el efecto del baño de agua en la consecuente ceniza y el impacto que
tiene mezclar su ceniza con la de corteza de Eucalyptus en cuanto a su comportamiento en fusión.
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