Abstract
Two-stage thermal gasification (carbonization and gasification) of wood chip and plywood from Japanese Larch was tried in a laboratory scale using CO2 as a gasification reagent. This gasification system is expected to decrease the emission of CO2 by recycling use as an oxygen carrier. The reaction of CO2 with char is known as boudouard reaction (C+CO2→2CO), and CO2 in the generated gas is considered as an unreacted gas. In this study, differences in the reaction rate of char and conversion rate of CO2 to CO between wood chip and plywood were discussed as well as reaction mechanism of char with CO2. Results obtained in this study show that the inorganic compounds, such as Ca or Na as additives to the adhesive for plywood used in this study, accelerated the gasification of plywood with CO2. In both samples, gasification temperature was an important factor on the reaction rate and conversion rate. Increasing of the CO2 flow rate accelerated the reaction rate of char with decreasing of conversion rate of CO2 to CO. It was suggested the new reaction mechanism of char and CO2 from the results. In this proposed route, CO2 was regenerated from the adduct of char-CO2 and competed with CO generation from the adduct.
