Abstract:
Biomass gasification driven by solar energy is a potential route for the syngas production as well as storage of unsteady solar energy. However, the influences of the non-homogeneous effects caused by unidirectional concentrated solar radiation on the gasification process were overlooked in existing studies, which in turn led to the inaccuracy of the developed models and design of solar reactor.
In this work, the on-line solar gasification experiments of char pellets derived from solar pyrolysis of willow wood were conducted at a temperature of 800-1500°C. The results showed that the special hierarchical structure of char pellet had little effect on the syngas yield, but led to a non-homogeneous gasification process characterized by the existence of two reaction stages.
CT scanning further revealed the evolution mode of the surface and the inner char pellets during the two gasification stages. The kinetic analysis based on gas-solid reaction model and charge conversion was combined and performed for the first time on the solar gasification. And the reaction mechanisms of two gasification stages from low-high temperature ranges were best described by the RPM-R3 and the R3-RPM, respectively.
The apparent activation energy of the two stages were 140.44 and 117.63 kJ/mol respectively. This work brought a new insight and methods for the study of solar gasification, and provided a theoretical basis for an accurate modelling of solar gasification as well as the design of solar reactor.
Zhong, D., Li, J., Li, J., Chen, X., Zeng, K., Flamant, G., Yang, H., & Chen, H. (2025). Overlooked non-homogeneous effects in solar gasification of biomass. Chemical Engineering Journal, 504, 158751. https://doi.org/10.1016/j.cej.2024.158751
