生物质炭水蒸气气化制取富氢合成气

摘要

Steam gasification of bio-char had been studied in an updraft fixed bed reactor for hydrogen-rich syngas. The effect of different feedstocks,particle sizes and catalysts on steam gasification was investigated. The results showed that there were big diversity between different char gasifications. The results of wood chip char gasification were the best,followed by the corn cob char and rice husk char;and the worst results were strew char gasification. The maximum hydrogen yield of wood chip char was 222.8g/kg char. Particle sizes mainly affected the char conversion rate,which increased with the increase of particle size. The method of char adsorbing catalysts was efficient,and the catalytic ability of KOH was better than K2CO3at the same potassium salts mass fraction. The gasification rate with catalyst were twice of that without catalyst. Moreover,the char conversion rate increased with the rising of alkali concentrations,but higher concentration was not favoable for the hydrogen yield due to the increase of ash content. The maximum hydrogen yield of corn cob char gasification was 197.8g/kg char with alkali concentration of 6%.%以生物质炭为原料在上吸式固定床气化炉中进行水蒸气气化制备富氢合成气,考察了不同原料、粒径和催化剂对生物质炭水蒸气气化影响.结果表明,不同类型炭气化结果存在较大差异,其中木片炭气化结果最优,其次是玉米芯炭和稻壳炭,秸秆炭气化结果最差,木片炭产氢率最大为222.8g/kg.粒径的改变主要影响炭转化率,炭转化率随着粒径的增加呈增加趋势.通过炭吸收方式负载催化剂为有效的方法,其中在相同钾盐质量分数下,KOH催化能力较优于K2CO3,且气化速率为未加催化剂条件下的两倍.炭转化率随着碱液浓度的增加而增加,但浓度过高会增加灰分含量从而不利于产氢率,玉米芯炭催化气化最高产氢率为197.8g/kg,在碱质量分数为6%下获得.