Abstract: Grape branches was used as the research object. The thermal degradation of grape branches was investigated at different heating rates in different atmosphere by using the thermo gravimetric-Fourier transform infrared spectroscopy(TG-FTIR). The results showed that there were some obvious weightlessness peaks in the DTG curves near 80, 350 and 800℃ in flue gas atmosphere(80% N₂, 15% CO₂, 5% O₂). When the heating rate was 30℃/min, the weight loss rates of the sample were about 80% in nitrogen atmosphere, and 95% in flue gas atmosphere. The transformation rate of grape branches could be raised and the amount of the gaseous products could be increased in flue gas atmosphere. The heating rate had a dual influence on the pyrolysis gasification process of grape branches. Improving the heating rate could increase the release of volatilization of grape branches and promote pyrolysis gasification reaction, but it would cause the charcoal coking, affecting the process of thermal weight loss. The pyrolysis products were analyzed by Fourier transform infrared spectroscopy, it showed that the gas phase products in different stages were various, and the precipitation characteristics of pyrolysis products were various, which were caused by restructuring and fracturing of internal functional groups of grape branches. The precipitated products of pyrolysis at 360℃ were the most, including small molecule gases such as CO, CO₂, H₂O, CH₄, and macromolecule substance such as aldehydes, hydrocarbons and carboxylic acids.

Key words: grape branches, pyrolysis and gasification, TG analysis, FTIR