Design and cold flow testing of a Gas-Solid Vortex Reactor demonstration unit for biomass fast pyrolysis

- Design of a Gas-Solid Vortex Reactor or GSVR for biomass fast pyrolysis.
- New features: single main gas inlet, profiled bottom end wall and diverging exhaust.
- Sufficiently high centrifugal-to-drag force ratio for sustaining a rotating bed.
- Stable rotating fluidized bed with average solids azimuthal velocities of 6-7 m s−1.

Innovative gas-solid fluidized beds with process intensification capabilities are among the most promising alternatives for the current state of the art in the chemical industry. In the present work the advantages of such a reactor that sustains a rotating fluidized bed with gas-solid slip velocities much higher than those in conventional fluidized beds are illustrated computationally and experimentally. A Gas-Solid Vortex Reactor (GSVR) demonstration unit is designed to operate at typical biomass fast pyrolysis conditions targeting the production of chemicals and fuels from renewable feedstocks. For the demonstration unit preheated N2 supplies the thermal energy required by the fast pyrolysis process but alternative sources can also be evaluated. A broad range of operation conditions in the 80 mm diameter and 15 mm height GSVR can be evaluated: N2 mass flow rates of 5-10 g s−1 and biomass feed mass flow rates of 0.14-1.4 g s−1. Particle-free and particulate flow experiments confirmed that the carrier gas is evenly distributed around the GSVR cylindrical chamber as anticipated by computational fluid dynamic simulations. The latter also supported the inclusion of a profiled bottom end wall and a diverging exhaust. Cold flow experiments with biomass confirmed that the GSVR sustains a rotating fluidized bed with average bed height of 10 mm and solids azimuthal velocities of 6-7 m s−1.

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