Optimal conditions for the gasification at the pilot scale of pine chips biomass feedstock with two different gasifying agents (air and an air/steam mixture) are determined. Ten experimental tests were performed at a fixed temperature, air stoichiometric ratio, and steam-to-biomass ratio. Results showed cold gas efficiencies circa 75 % (air) and 95 % (air/steam), yielding ∼3 Nm3syngas/kgbiomass, in both cases, and lower heating values of 7.6 and 8.5 MJ/Nm3, respectively. Hydrogen production and process performance were assessed and compared to those found in literature, showing a good performance considering biomass, ca. 35 g H2/kg biomass. A techno-economic model fed with the experimental results obtained was validated. The model established that air gasification could be more profitable for energy than air/steam gasification, especially at higher scales. The internal return rate was less than 1.5 years; nevertheless, air/steam mixture as a gasifying agent more adequate for H2/biofuel production.
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