Abstract: For efficiently utilizing the agricultural biomass wastes through pyrolysis and gasification， thermogravimetric and mass spectrometry experimentation of corn cob， peanut shell， rice husk and rice straw were performed by thermogravimetric analysis and mass spectrometry. Mechanism of weightlessness， regularities of heat flow and the releasing combustible and small moleacule and small moleacule gases (CO， H₂ and CH₄) as well as the pyrolysis characteristics were thoroughly studied. The results showed that the weight loss of biomass mainly occurs within 220~410℃. As for corn cob， the weightlessness between 220℃ and 410℃ is the highest， which accounts for 80%~90% of the total weight loss. The pyrolysis index D is corn cob > rice straw > rice husk > peanut shell. The activation energy is rice husk > corn cob > rice straw > peanut shell. The char yield is rice husk > peanut shell > rice straw > corn cob. Generally， thermal stabilities of corn cob and rice straw are poor while thermal stabilities of rice husk and peanut shell are relatively stable. The activation energy and frequency factor are obtained by Coasts-Redfern method. Numerical results show a good consistency with thermogravimetric data.

Key words: biomass, pyrolysis, thermogravimetric analysis, mass spectrometry, kinetics