A simple expression for the apparent reaction rate of large wood char gasification with steam.
A simple expression for the apparent reaction rate of large wood char gasification with steam is proposed. Large char samples were gasified under steam atmosphere using a thermo-balance reactor. The apparent reaction rate was expressed as the product of the intrinsic rate and the effective factor. The effective factor was modified to include the effect of change in char diameter and intrinsic reaction rate during the reaction. Assuming uniform conversion ratio throughout a particle, the simplified reaction scheme was divided into three stages. In the initial stage, the local conversion ratio increases without particle shrinkage. In the middle stage, the particle shrinks following the shrinking core model without change in the local conversion ratio. In the final stage, the local conversion ratio increases without particle shrinkage. The validity of the modified effective value was confirmed by comparison with experimental results.
Department of Environmental Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho 4259/G5-8, Midori-ku, Yokohama 226-8502, Japan. kent.ume@gmail.com
Kentaro
K
Umeki
Seon-Ah
SA
Roh
Tai-Jin
TJ
Min
Tomoaki
T
Namioka
Kunio
K
Yoshikawa
D005740:Gases; D007700:Kinetics; D013227:Steam; D014934:Wood
D005740:Gases; D013227:Steam