| Issue |
Korean Journal of Chemical Engineering,
Vol.16, No.4, 456-461, 1999
Vol.16, No.4, 456-461, 1999
Gas Backmixing in the Dense Region of a Circulating Fluidized Bed
The gas backmixing characteristics in a circulating fluidized bed (0.1 m-ID×5.3-m high) have been determined. The gas backmixing coefficient(Dab) from the axial dispersion model in a low velocity fluidzation region increases with increasing gas velocity. The effect of gas velocity on Dab in the bubbling bed is more pronounced compared to that in the Circulating Fluidized Bed (CFB). In the dense region of a CFB, the two-phase model is proposed to calculate Dab from the two-phase model and mass transfer coefficient (k) between the crowd phase and dispersed phase. The gas backmixing coefficient and the mass transfer coefficient between the two phases increase with increasing the ratio of average particle to gas velocities(Up/U g).
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[Cited By]
- Kim SW, Ahn JY, Lee DH, Kim SD, Korean Journal of Chemical Engineering, 18(4), 555, 2001
- Namkung W, Kim SW, Kim SD, HWAHAK KONGHAK, 38(4), 523, 2000
- Kim J, Han G, Yi C, Korean Journal of Chemical Engineering, 19(3), 491, 2002
- Kim SD, Kim YH, Roh SA, Lee DH, Korean Journal of Chemical Engineering, 19(5), 911, 2002
- Song PS, Jeong YY, Yun JS, Choi GS, Kang Y, Kim SD, Korean Journal of Chemical Engineering, 19(6), 1043, 2002
- Namkung W, Kim SW, Kim SD, Korean Journal of Chemical Engineering, 20(1), 110, 2003
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