Abstract
Accurate prediction of transport phenomena is critical for VPU reactor design, optimization, and scale-up. The current study focused on the validation and application of a multiphase CFD model within an open-source code MFiX for hydrodynamics, temperature field, and residence time distribution (RTD) simulation in a non-reacting circulating fluidized bed riser for biomass pyrolysis vapor phase upgrading (VPU). First, an Eulerian-Eulerian approach three-dimensional CFD model was employed to simulate the pilot-scale VPU riser on the supercomputer Joule. Excellent quantitative agreement between experimental and simulated results was achieved for pressure drops and temperature field in a range of operating conditions. Then the validated multiphase CFD model was applied to predict gas and solid residence time distributions (RTDs) since prediction and analysis of RTD is an important tool to study the complex multiphase flow behavior and mixing inside chemical reactors. The predictions show that solid mean residence time is 3.5 times the gas residence time; the solid RTD is more sensitive to the process gas flow rate than the solids circulation rate.
Original language | English |
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Article number | 124279 |
Journal | Chemical Engineering Journal |
Volume | 388 |
DOIs | |
State | Published - May 15 2020 |
Funding
This work was performed in support of the US Department of Energy's EERE Bioenergy Technologies Office (BETO) as part of the BETO Consortium for Computational Physics and Chemistry (CCPC). The Research was executed through the NETL Research and Innovation Center's BETO CCPC. Research performed by Leidos Research Support Team staff was conducted under the RSS contract 89243318CFE000003. Research performed in part by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. This work was performed in support of the US Department of Energy’s EERE Bioenergy Technologies Office (BETO) as part of the BETO Consortium for Computational Physics and Chemistry (CCPC). The Research was executed through the NETL Research and Innovation Center’s BETO CCPC. Research performed by Leidos Research Support Team staff was conducted under the RSS contract 89243318CFE000003. Research performed in part by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308.
Keywords
- Biomass
- Hydrodynamics
- MFIX
- Residence time distribution
- Vapor phase upgrading