TY - GEN
T1 - Solids holdups in the fully developed region of circulating fluidized beds
AU - Qi, Xiao Bo
AU - Zhu, Jesse
AU - Huang, Wei Xing
AU - Hui, Zhang
PY - 2006
Y1 - 2006
N2 - The present work focuses on developing correlations for better prediction of solids holdups in the fully developed region of cocurrent upflow and downflow two-phase flow. Systematic experiments were carried out in two CFB risers (15.1m and 10.5m high, respectively, but with the same 0.1 m i. d.) and a 9.3 m high, 0.1 m i. d. CFB downer. The experimental results obtained from about 200 sets of operating conditions, under which the lengths of fully developed section are longer than 2.8 m, show that when the superficial gas velocity is between 3 m/s and 8 m/s, it has a significant effect on the variations of the average solids holdups in the fully developed region with the terminal solids holdups, but when it is less than 3 m/s or greater than 8 m/s, the effect becomes weak and the average solids holdups vary linearly with the terminal solids holdups. By taking into account the effects of superficial gas velocity, particle properties and riser geometry, two empirical correlations for predicting the average solids holdups in the fully developed region of CFB riser and downer were proposed, respectively. These correlations are in good agreement with the experimental data of this work and accords with the correlations reported in literatures.
AB - The present work focuses on developing correlations for better prediction of solids holdups in the fully developed region of cocurrent upflow and downflow two-phase flow. Systematic experiments were carried out in two CFB risers (15.1m and 10.5m high, respectively, but with the same 0.1 m i. d.) and a 9.3 m high, 0.1 m i. d. CFB downer. The experimental results obtained from about 200 sets of operating conditions, under which the lengths of fully developed section are longer than 2.8 m, show that when the superficial gas velocity is between 3 m/s and 8 m/s, it has a significant effect on the variations of the average solids holdups in the fully developed region with the terminal solids holdups, but when it is less than 3 m/s or greater than 8 m/s, the effect becomes weak and the average solids holdups vary linearly with the terminal solids holdups. By taking into account the effects of superficial gas velocity, particle properties and riser geometry, two empirical correlations for predicting the average solids holdups in the fully developed region of CFB riser and downer were proposed, respectively. These correlations are in good agreement with the experimental data of this work and accords with the correlations reported in literatures.
KW - Circulating fluidized beds
KW - Downer
KW - Gas/solid flow
KW - Riser
KW - Solids holdup
UR - http://www.scopus.com/inward/record.url?scp=57049129259&partnerID=8YFLogxK
M3 - Conference contribution
AN - SCOPUS:57049129259
SN - 081691012X
SN - 9780816910120
T3 - AIChE Annual Meeting, Conference Proceedings
BT - 2006 AIChE Annual Meeting
T2 - 2006 AIChE Annual Meeting
Y2 - 12 November 2006 through 17 November 2006
ER -