Experimentos de combustión con cascarilla de arroz en lecho fluidizado para la producción de ceniza rica en sílice

Aiming to contribute with the valorization of agricultural wastes that present disposal problems and the use of renewable energy sources, was researched the rice husk combustion in atmospheric bubbling fluidized bed reactor. The methodology was to evaluate the air excess influence in the flue gases and the ash characteristics. It was determined the gases composition (CO, CO₂ and NO_x) and characterized the ash generated (XRD, XRF). 40% excess air promotes temperatures inside the reactor around 700°C with higher conversion efficiencies, but declining the amorphous silica potential of the ash. Contrary behavior was evidenced at 128% excess air. The flue gases showed relative variability for each operating condition. In the CO case, an average concentration of 200 ppm was found (on a dry basis of 11% O₂) for air excess between 40% and 82,5%.