A study has been conducted on the se
lection of a d
raft tube and its pe
rfo
rmance on a pi
lot sca
le conica
l spouted bed
reacto
r used in the fast py
ro
lysis of biomass waste. The nonpo
rous d
raft tube confe
rs high stabi
lity to the bed and, fu
rthe
rmo
re,
reduces the f
luidizing agent f
low
rate, which means significant ene
rgy saving. The goa
l of the study is the optimization of the geomet
rica
l facto
rs of the inte
rna
l device in o
rde
r to achieve suitab
le ope
rating conditions, given that they have a g
reat inf
luence on bed hyd
rodynamics and, the
refo
re, on heat t
ransfe
r cha
racte
ristics,
residence time of the vo
lati
les in the
reacto
r and py
ro
lysis kinetics.
The criteria for the selection are based on a compromise between gas flow rate and solid circulation rate in a bed operating under stable conditions. Moreover, studies have also been carried out on the performance of wood/sand mixtures and the critical elutriation diameter. The results show that a draft tube conical spouted bed operated with a suitable flow rate gives way to very good mixing, elutriation of light particles and short gas residence times.