农业生物质在超临界水中气化制氢的实验研究

Experimental Investigation on Hydrogen Production by Agricultural Biomass Gasification in Supercritical Water

以农业生物质(包括玉米秸秆、玉米芯、麦秸、稻草、稻壳、花生壳、高粱秆)为原料,羧甲基纤维素钠为添加剂,利用连续管流反应器,在反应器壁温为 650 ℃、压力为 25 MPa的条件下进行了生物质气化制氢实验研究.讨论了运行时间、生物质类型、颗粒大小、反应器壁面状况等因素对气化结果的影响.实验结果表明:农业生物质在超临界水中气化生成以氢气、二氧化碳、一氧化碳、甲烷以及少量的乙烷和乙烯为主要成分的气体;气化周期内大约经过100 min气体产物组成以及产量趋于稳定;在相同的实验条件下不同生物质气化得到了相似的气体组分,气体产物中一氧化碳体积分数大约为 1%,甲烷体积分数超过 10%,氢气的体积分数最高可以达41 28%;小颗粒的生物质气化能生成更多的氢气;反应器壁面对生物质气化有明显的催化作用.

Hydrogen can be obtained by thermochemical gasification of biomass in supercritical water. Agricultural biomass, including corn stalk, corn cob, wheat stalk, rice straw, rice shell, peanut shell, wood sawdust and broomcorn stalk, mixed in sodium carboxymethylcellulose, were gasified successfully at 650°C, 25 MPa in a tubular flow reactor with formation of hydrogen, carbon dioxide, carbon monoxide, methane and a small amount of ethane and ethylene. The influences of operation time, type of biomass, particle size and reactor wall on biomass gasification were investigated. The experimental results show that the similar gas composition is obtained from gasification of different agricultural biomass on the same operation conditions. The volume fraction of carbon monoxide in product gas is about 1%, the volume of methane is in excess of 10% and the maximal volume fraction of hydrogen reaches to 41.28%. And small particle is favorable to hydrogen yield and the reactor wall catalyzes obviously the biomass gasification.