为深入分析生物甘油水蒸气自热重整制氢强化过程以实现高效制氢,采用吉布斯自由能最小原理,研究氢气分离与二氧化碳吸附两种强化手段对甘油自热重整过程的影响,分析氢气产量、积碳量与反应热随温度、氢气分离系数等参数的变化规律.结果表明:氢气的分离会大大提高氢气的产量,抑制甲烷的生成,但会导致积碳量增加.氢分离会增加对反应热的需求,为达到自热,需要更高的氧气-甘油投料比.氧化钙作为二氧化碳吸附剂,在750 K以下由于生成氢氧化钙而降低氢气的产量;当温度高于800 K时,碳酸钙分解会降低吸附剂对二氧化碳的吸附能力,故氧化钙的吸附温度应控制在750～800 K.二氧化碳吸附所放出的热量可以使甘油重整实现自热.%To understand the enhancing process of autothermal glycerol steam reforming for high efficient hydrogen production, the effects of two enhancing approaches including hydrogen separation and carbon dioxide absorption are evaluated based on Gibbs free energy minimization method. The variation of hydrogen yield, deposited carbon and reaction heat varied with temperature and hydrogen separation fraction are analyzed. The results reveal that the hydrogen separation can promote the hydrogen yield and restrict the methane production, while this process leads to the increase of carbon formation. The hydrogen removal increases the reaction heat, and a higher oxide to glycerol feed ratio is required to achieve the autothermal condition. Calcium oxide absorbs carbon dioxide to generate calcium hydroxide below 750 K, which leads to reduction of hydrogen yield. When the temperature reaches above 800 K, the capacity of sorbents becomes weak owing to the decomposition of calcium carbonate. Hence, the temperature from 750 K to 800 K is suitable for absorption reaction. The autothermal process can be attained with the heat from absorption reaction.
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