Study on pine biomass air and oxygen/steam gasification in the fixed bed gasifier

摘要

The pine biomass gasification under air and oxygen/steam atmosphere was experimentally studied in a fixed bed reactor. The effects of air flow, gasification temperature, oxygen concentration, steam flow and the catalytic cracking reaction temperature on production distribution were investigated. The results indicate that the H_2 content reaches the maximum at the gasification temperature 850 ℃ for a given air flow. Comparing with air-gasification atmosphere, the lower heating value (LHV) of produced syngas is higher (up to 8.76 MJ/Nm~3) under oxygen-enriched gasification atmosphere. And the introduction of steam to the oxygen-enriched gasification leads to a higher H_2 content and LHV of produced synthesis gas. Additionally, the syngas content increases significantly with increasing catalytic cracking reaction temperature when Ni-Al_2O_3 catalyst was employed in catalytic cracking process. The results also reveal that the steam reforming reactions of methane and carbon dioxide are enhanced over Ni-Al_2O_3 catalyst. The effects of different loading of metal oxide additives to Ni-Al_2O_3 catalyst on the catalytic activity were discussed, and it is found that the Fe_2O_3/Ni-Al_2O_3 catalyst shows the best catalytic activity and the H_2 content achieves the maximum value of 39.21 vol.%.