Industrial & Engineering Chemistry Research, Vol.59, No.25, 11893-11904, 2020
Research on Fluidization Performance of Different Tapered Fluidized Bed Reactors for Fluidizing Carbon Nanotubes
In this work, the tapered fluidized bed reactor (TFBR) without a distributor is used for the first time in the production of carbon nanotubes (CNTs), in which, the periodic motion process of CNT particles is elaborated through visual and image observations. The fluidization behavior and quality of the agglomerated multiwalled carbon nanotubes (MWCNTs) ((@)A) and vertical array MWCNTs (V-@) in TFBRs with/without a distributor and with different tapered angles are carefully studied, including C-1 (60 degrees), C-2 (25 degrees), and C-3 (11 degrees). The performances of different TFBRs are evaluated qualitatively and quantitatively by using the bed collapse method and the dimensionless time Theta. Results show that the tapered angle of C-3 in the TFBR with a distributor is beneficial to fluidize CNTs, and the fluidization behavior of CNT particles can be changed by varying the tapered angle of TFBRs. The results of fluidization quality (Theta(1/4)) in C-3-N (without a distributor) and C-3 (with a distributor) have shown that C(3)(@)A (0.0.07035) < C(3)(@)A-N (0.1545), (C3V)-V-@ (0.1479) < (C3V)-V-@-N (0.1867), which verify that the fluidization quality of (@)A and V-@ particles in the TFBR without a distributor is better than that with a distributor. Furthermore, due to the less requirement of the gas source cost in this study, the TFBR without a distributor technology as a promising technique for mass production of CNTs in a cost-effective way has been confirmed.