Hydrogen-Enriched Syngas from Biomass Steam Gasification for Use in Land-Based Gas Turbine Engines - Novel Combustion Concepts for Sustainable Energy Development - page 93

Fig. 5 Comparison of
hydrogen concentration at
similar run conditions
(S/B = 0.8 ± 0.25,
τ = 2.0 ± 0.5)

ciency is also compared to published data at similar tempera-
tures and S/B ratios and is shown in Fig. 6 (Corella et al. 1991 ; Franco et al. 2003 ;
Xu et al. 2004 ). The cold gas ef

The cold gas ef

ciency is reported less frequently than hydrogen
concentration, as a result the residence times could not be perfectly matched. The
cold gas ef ciency is de ned as follows:

Þ¼ m syngas

HHV syngas

Cold Gas Efficiency CGE ð

m b

HHV b

where subscript b denotes the biomass. Variation in residence time, gasi er shape,

feedstock, feedstock entry points, and method of heating all effect CGE. Wei et al.
( 2006 ) used a dual

er system that burned a portion of the char in
a separate chamber. This is a possible reason why their reported ef

fl fluidized bed gasi

ciency is lower.
Additionally, Corella et al. ( 1991 ) injected biomass at the top of the fl fluidized bed,

resulting in lowered gasi cation ef ciency. Despite these differences, the trend of

Fig. 6 Comparison of
temperature effect on cold gas
ef ciency (S/B = 0.8,
τ = 2.2 s)