Open AccessMethod for Thermal Design of Paddle Dryers: Application to Municipal Sewage Sludge
Author(s) -
Patricia Arlabosse,
Sofia Chavez,
Didier Lecomte
Publication year - 2004
Publication title -
hal (le centre pour la communication scientifique directe)
Language(s) - English
DOI - 10.1081/ldrt-200040041
Subject(s) - paddle , environmental science , sewage sludge , waste management , sewage , thermal , thermal hydrolysis , environmental engineering , sewage sludge treatment , sewage treatment , engineering , mechanical engineering , physics , meteorology
International audienceAn experimental methodology was developed to improve the energy design of paddle dryers for sewage sludges. A laboratory batch dryer with a vertical agitator has been especially designed and instrumented to determine the heat flux densities. To determine the drying kinetic and the evaporating flow rates, the specific heat and the total heat of desorption of the sludge were measured using calorimetric devices. The evaporating flow rates recorded during the pasty and granular phases were then used in a simple model of the paddle dryer. The good agreement between the computed drying kinetics and the experimental ones measured in an industrial paddle dryer shows that the batch dryer can be used to classify the sludges according to their capacity to be dried in a paddle dryer