生物质气流床气化特性及残炭特性的研究

Biomass entrained flow gasification and residue behavior

为了考查反应温度及氧气和生物质质量比对生物质煤气组分、碳转化率、气化产物分布以及残炭特性的影响，利用一套小型生物质气流床气化系统进行了木屑的气化试验．结果显示，随着反应温度升高，H2的体积分数显著增加，而CO2的体积分数则明显减少，其中高温段（1000-1400℃）H2和CO合成气总体积分数达到了80％以上；CH4体积分数则随着反应温度的升高先增加后减少，到1400℃时，可忽略不计；1400℃时，液体产物的质量分数只占到总产物的8％～10％，说明高温气化焦油量很少；随着反应温度升高，碳转化率随之迅速升高，到1400℃时达到95％，其中600～800℃是木屑碳转化率升高最快的阶段；木屑的煤气产率也随温度升高而增高，到1400℃时，煤气产率最高达到91％．

A lab-scale biomass entrained flow gasification system was used to test sawdust gasification in order to investigate the effects of reaction temperature and the mass ratio of oxygen to biomass on biomass gasification performance including gas composition, carbon conversion, products distribution and solid residue behavior. Results showed that H2 volume fraction increased and CO2 volume fraction decreased with the reaction temperature increasing; syn-gas composition in high temperature （1 000-1 400℃ ） reached above 80 %. CH4 volume fraction increased firstly and then decreased with the reaction temperature increasing, at last CH4 volume fraction was very little at 1 400℃. The liquid product mass fraction reached only about 8%-10% at 1 400 ℃ which indicated that the tar content was very low. The carbon conversion rate increased to a maximum value 95% at 1 400℃ with the reaction temperature increasing; the high carbon conversion rate appeared between 600℃ and 800 ℃. The gas product yield rate increased with the reaction temperature increasing and it reached to a maximum value 91% at 1 400℃.