摘要
为了解操作条件对生物质在超临界水中气化制氢过程的影响,该文以松木屑作为原料,在反应温度500℃、反应压力30 MPa、停留时间30 min、木屑质量分数8%、粒径8~16目的条件下,探索了Fe、Na2CO3、Cu SO4 3种催化剂对制氢过程的催化活性:Fe>Na2CO3>Cu SO4。选用Fe催化剂,考察了反应压力30 MPa、停留时间30 min、反应温度(420~500℃)、木屑质量分数(8%~40%)、粒径(2~1 000目)对制氢过程的影响。试验结果表明:Fe催化剂质量分数增大,能显著提高制氢效果;随着温度的升高,气化率、碳气化率、氢气化率及氢气产量均相应增大;木屑质量分数越低,气化率和氢气化率越高;粒径对气化结果影响不大;在优化后的操作条件下(反应温度500℃、反应压力30 MPa、停留时间30 min、Fe质量分数2%、松木屑质量分数8%、粒径8~16目),H2的摩尔分数、氢气化率、氢气产量分别达到42.1%、98.1%、6.62 mol/kg。该文研究结果可为该技术今后的工业化发展和应用提供参考。
Biomass is a kind of renewable raw material and it is the 4th largest energy in the world due to its abundant total resource reserve. Biomass is considered to be a future energy because it is renewable, abundant and carbon neutral. However, because of its loose structure and low energy density, biomass has low direct utilization efficiency. Technologies of hydrogen production from biomassinclude biomass gasification technology, biomass pyrolysis technology and biomass supercritical water gasification technology currently. Hydrogen production from biomass gasification technology is easy to produce the tarry material and has low gasification rate. Hydrogen production from biomass pyrolysis technology can not directly handle wet biomass, which needs dehydrating. However, hydrogen production from biomass by supercritical water gasification is a kind of clean and efficient hydrogen production technology, which has been developed recently. It can directly handle the biomass with high moisture content, and need not the drying process with high energy consumption; it can obtain the high gasification rate and effectively overcome the above problems of biomass gasification technology and biomass pyrolysis technology. Therefore, it has become an international hot technology for biomass utilization. The technology is based on a series of unique properties of supercritical water, such as low dielectric constant, low viscosity and high diffusion coefficient, and uses supercritical water as the reaction medium; and the conversion from biomass to H2 is completed in hot compressed water with the temperature and pressure above the critical values (647 K and 22.1 MPa). Many researches of hydrogen production from biomass with supercritical water gasification technology have focused on the effects of different operating conditions (reaction temperature, reaction pressure, reactant mass fraction, residence time, catalyst, etc.) on the biomass (mainly the compound concentration, such as cellulose and glucose) and its inherent mechanism
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2015年第24期256-261,共6页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家科技支撑计划课题(2014BAJ01B00
2014BAJ01B06)
关键词
气化
氢
水
松木屑
超临界
gasification
hydrogen
water
pine wood sawdust
supercritical
