Title:
A CFD-method for the Analysis and Optimization of the Fixed Bed Conversion in Biomass Grate Furnaces
Author(s):
Singer, M., Mehrabian, R., Gruber, T., Anca-Couce, A., Scharler, R.
Document(s):
Paper
Poster
Abstract:
To optimize the combustion of biomass grate furnaces a sensitivity analysis is carried out by means of CFD simulation. The methodical procedure consists of a 3D packed bed biomass combustion model, which describes the most essential characteristics of the thermal conversion of biomass particles, such as the detailed consideration of drying, pyrolysis and char oxidation in parallel processes. Within the sensitivity analysis the following parameters have been investigated: distribution of false air, residence time of fuel on the grate and distribution of recirculated flue gas and primary air below the grate. To evaluate the influence of the varied parameters on the combustion process the focus lied on the position of the thermal conversion of the biomass and the CO at the outlet of the simulation domain. The results of the sensitivity analysis show a shift of the thermal conversion towards the grate end for increased false air as well as for reduced momentum of primary air/recirculated flue gas mixture. An increase of the fuel residence time leads to a shift of the thermal conversion towards the fuel inlet. Consequently a large region of the primary combustion zone is not used due to earlier release of CO inside the fuel bed.
Keywords:
combustion, efficiency, grate furnace, CFD optimization
Topic:
Biomass Conversion Technologies for Heating, Cooling and Electricity
Subtopic:
Biomass and bioliquids combustion for small and medium scale applications
Event:
27th European Biomass Conference and Exhibition
Session:
2BV.4.17
Pages:
688 - 693
ISBN:
978-88-89407-19-6
Paper DOI:
10.5071/27thEUBCE2019-2BV.4.17
Price:
FREE