COMBUSTION DE PREMELANGES AIR-GAZ NATUREL EN REACTEUR LIT FLUIDISE : ETUDE EXPERIMENTALE DE LA ZONE DE DESENGAGEMENT
The combustion of natural gas - air mixtures in fluidised bed reactors containing inert media has been investigated experimentally at dense bed temperatures ranging between 650 and 800 °C. During this study, the effects of the excess air factor, the dense bed height at minimum fluidising velocity, the superficial gas velocity and the solid particles mean diameter were examined. The obtained results has permitted to determine some limit bed temperature, which arounds 800 °C, below which the whole reactor behaviour is governed by phenomena taking place in the freeboard region. In this situation, among the studied operating parameters, only the dense bed temperature, the superficial gas velocity and the particles mean diameter exert an important effect on the system evolution.