CIRCULATING FLUIDIZED BED GASIFICATION FOR SYNGAS GENERATION - MODELING AND MODEL VALIDATION

摘要

Over the years many researchers made attempts to develop anmodel of the fluidized bed gasification process, mostly aimed atnsimulating air-blown gasification1-6. The most recent and a veryncomprehensive review about the modeling of biomass gasification inna fluidized bed is given by Gomez-Barea7. Another extensivenoverview is given by De Jong8. The researchers mentioned aboveneither set-up a model using some kind of simulation software orndeveloped their own code to simulate the fluidization andngasification process or certain aspects of it. De Souza-Santosndeveloped a comprehensive simulation software, which is able tonmodel fixed, bubbling and circulating fluidized beds, both inncombustion and in gasification mode5. This software is commerciallynavailable9. However, the use of existing models has a number ofnpractical limitations, the main being the lack of access to the sourcencode and its documentation. Until now no model is available that isnable to simulate all phenomena of interest to the researchers workingnon fluidized bed gasification, therefore often an adaptation to one’snneed may be necessary. This is not possible without the access to thensource code. Also the understanding or fixing of modeling bugs thatnare present even in the commercial software is impossible in thatnway. On the other hand, setting up a new model from scratch maynnot be the most efficient way to proceed either. Therefore it wasndecided to use an available model code developed for a similarnprocess and extend it with features necessary to simulate steamoxygennblown gasification of biomass in a CFB aimed at producing anraw syngas for downstream upgrading to e.g. transportation fuels