Figure 1

Schematic diagram of the fluid dynamic reactors equipped with helical ribbon stirrer. The reactor was a cylinder equipped with a helical ribbon stirrer. The parameters of the helical ribbon stirrer were matched with the change in the diameter of the reactor to keep the character of the helical ribbon the same in the three reactors. The mixing time was calculated by the time to reach constant moisture of corn stover in the reactors. d, diameter of impeller (mm); D, diameter of the reactor (mm); S, pitch size of the helical ribbon (mm); w, ribbon width (mm).