Valorização do esterco avícola como biomassa para aproveitamento na geração de energia por combustão.

Abstract

Brazil is among the largest egg and chicken producers in the world and in the next decade 45% increase in the productive sector is expected. Associated with this increase is the inadequate disposal of poultry manure, a problem that producers face because of its great polluting potential, which can contaminate soils, water bodies, and spread diseases, in addition to having a strong odor. This study aimed to characterize and analyze dry poultry manure from an energy point of view using thermogravimetric and calorific value analysis data. Drying was analyzed in a convective tray dryer with parallel air flow, under conditions of 1.0, 1.2, and 1.4 m/s for air velocity, 60, 70, and 80°C for air temperature, and solid layers 0.5 and 1.0 cm thick. It was found that the air velocity did not have a significant impact on drying, on the other hand, the increase in temperature significantly influenced the drying time and the reduction of the humidity of the poultry manure, making it possible, from the thermal analysis, to identify good combustibility, reactivity, and average calorific value of 11.89 MJ/kg. However, there were no significant variations for the thermal parameters obtained from the thermogravimetric analysis and the calorific value as a function of the operating conditions used in drying. Instead of the high content ash of the poultry manure, 29,58%, the poultry manure showed good results for combustibility such as an ignition temperature of 222°C, peak combustion temperature of 423°C, a burnout temperature of 511°C, calorific value of 11.89 MJ/kg, and the combustion index of 2.3x10-7. Finally, the results indicate that poultry manure has great potential as a fuel, due to its low added value, high reactivity, combustibility and low ignition and burnout temperatures, but its high ash content reduces combustion efficiency, and high levels of nitrogen and minerals can indicate the production of polluting gases.