Two pumpable, water-based, coal-biomass slurries were prepared, bottom-injected and tested in an experimental program at pilot-scale for atmospheric bubbling bed gasification with air. The bed was made of either alumina particles or alumina-supported catalysts of the same size and operated at about 850°C. The equivalence ratio, which was selected as the main operating variable, was in the range =0.3-0.49. The fluidization velocity was U=0.4 m/s; the jetting ratio, which was the ratio of the air flow rate for slurry dispersion to the overall air flow rate, was J=0.25. The complex slurry gasification mechanism determines poor gasification efficiency. The switch from a bed of non-catalytic solids to one of Ni-supporting -alumina particles is effective in converting within the bed up to half of the generated tars. However, this advantage is offset by an enhanced carbon loss from the bed of the gasifier.
On the mechanism of coal-biomass slurry fluidized bed gasification
MICCIO, Michele
Writing – Review & Editing
;
2012-01-01
Abstract
Two pumpable, water-based, coal-biomass slurries were prepared, bottom-injected and tested in an experimental program at pilot-scale for atmospheric bubbling bed gasification with air. The bed was made of either alumina particles or alumina-supported catalysts of the same size and operated at about 850°C. The equivalence ratio, which was selected as the main operating variable, was in the range =0.3-0.49. The fluidization velocity was U=0.4 m/s; the jetting ratio, which was the ratio of the air flow rate for slurry dispersion to the overall air flow rate, was J=0.25. The complex slurry gasification mechanism determines poor gasification efficiency. The switch from a bed of non-catalytic solids to one of Ni-supporting -alumina particles is effective in converting within the bed up to half of the generated tars. However, this advantage is offset by an enhanced carbon loss from the bed of the gasifier.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.