通过吉布斯自由能最小化法对生物质半焦与载氧体CuO之间的反应进行热力学计算,研究温度、载氧体量及压力对生物质半焦化学链气化的影响。同时采用热重分析及扫描电镜等技术手段对生物质半焦/载氧体CuO的反应特性进行了实验研究。结果表明,载氧体CuO能有效促进生物质半焦的气化,随着反应温度的升高,生物质半焦气化效率提高,但当温度超过750℃,CuO载氧体开始出现烧结现象;其半焦/载氧体CuO的化学链气化最佳质量比为1∶6。研究也发现,反应压力的增加对生物质半焦的化学链气化有一定的抑制作用。
Calculations of reactions between biomass char and oxygen carriers CuO were conducted via the method of Gibbs free energy minimization. The effect of temperature, mass ration of oxygen carder/biomass char and pressure on the gasification of biomass char was examined. The reactions were experimentally investigated using thermogravimetric analysis and scanning electron microscopy (SEM). The results show that when using CuO as oxygen carrier in chemical looping gasification (CLG) of biornass char, the conversion rate of biomass char is improved with increasing reaction temperature. The oxygen carder CuO starts to sinter when the reaction temperature is above 750 ℃. The addition of oxygen carrier has the best enhancement on the CLG of biomass char with mass ratio of biomass char/CuO being 1:6. It is also found that the increase of reaction pressure would inhibit the CLG of biomass chars.