Comparative Study for the Energy Valorisation of Rice Straw

Abstract

The processes of pyrolysis and combustion of rice straw were simulated by multi-rate linear non- isothermal thermogravimetric experiments under Ar and O2 respectively. The kinetic parameters and thermal stability of both thermo-chemical processes were assessed and compared under different linear heating rates. From the results obtained from TGA, the kinetic methodology (combination of Friedman, Kissinger- Akahira-Sunose, Vyazovkin and Master-Curves methods) permitted to describe mathematically the decomposition processes of rice straw. The use of all the applied atmospheres showed 4 different decomposition stages, corresponding to the main degradation processes (drying and cellulose, hemicellulose and lignin decomposition). Reactions were faster when increasing the content of O2 in the carrying gas as a result of a higher reactive atmosphere and the percentage of ashes decreased, as well as the final temperature of each degradation stage.