煤和生物质共气化制备富氢气体的实验研究

Experimental study on hydrogen-rich gas production by co-gasification of coal and biomass in a fluidized bed

在煤处理量为8kg/h的小型流化床反应器上,以富氧空气和水蒸气为气化介质,对煤和生物质共气化制取富氢燃气进行了实验研究。在850℃～1 050℃主要考察了空气当量比、水碳比、生物质比例和生物质种类对燃气组成和气体产率的影响。结果表明,对煤和稻草混合体系,稻草质量比为33%时,空气当量比增加,CO2含量显著增加,H2、CO和CH4含量减少,气体产率增加;水碳比增加,CO2和CH4含量增加,CO和H2含量减小,气体产率先增加后减小;生物质比例增加,CO2、H2和CH4含量增加,CO含量降低,气体产率先增加后减小,当生物质比例小于50%时,可以实现体系的稳定运行。对于三种不同的煤与生物质混合体系,煤与高粱秆共气化所得煤气中H2含量最高,气体产率的顺序为:煤/木屑>煤/高粱秆>煤/稻草>煤。实验中H2在煤气中的体积分数最高可达37.25%,最大产率为0.54m3/kg。

The hydrogen-rich gas production by co-gasification of coal and biomass was studied in a bench-scale fluidized bed and the effects of Equivalence Ratio（ER）,steam/carbon ratio（Fs/Fc）,biomass/coal ratio and biomass type were examined in the temperature range of 850℃～1050℃.The results show that the concentration of carbon dioxide and gas yield increase with the rise of ER,while the concentrations of carbon monoxide,hydrogen and methane decrease.With the increase of Fs/Fc weight ratio,the concentrations of carbon dioxide and methane increase,while those of carbon monoxide and hydrogen decrease,and the gas yield decreases following a slight increase.The concentration of carbon dioxide,hydrogen and methane increases with the increase of biomass/coal ratio,but that of carbon monoxide decreases,and the gas yield increases at first and then decreases.Coal and biomass blend can be co-gasified with as high as 50% of biomass.Among the three types of biomass used,coal/sorghum stalk gasification has the highest hydrogen concentration,and the order of gas yield for various fuels is as follows： coal/pine sawdustcoal/sorghum stalkcoal/rice strawcoal.In this experiment,the maximum volume content of hydrogen in gas and hydrogen yield can reach 37.25% and 0.54m3/kg,respectively.