地沟油化学链强化重整制氢工艺热力学分析

Thermodynamic Analysis of Hydrogen Production via Sorption-Enhanced Chemical Looping Reforming of Waste Cooking Oil

以地沟油为原料的化学链强化重整制氢系统,不仅节省化石燃料,同时减少CO2等温室气体排放。利用Aspen Plus对该系统进行建模,以产品气组成（干基）,H2产率（Y）和系统火用效率（η）为系统性能评价指标,分析NiO循环量与进料碳摩尔比（NiO/C）,进料水蒸气量与进料碳摩尔比（S/C）,CaO循环量与进料碳摩尔比（Ca/C）对系统性能的影响。结果表明,Ni O/C在0.5-1.8区间变化时,产品气中H2体积分数降低0.01左右,Y及η减少;S/C在1-5区间变化时,产品气中H2含量从0.85升到0.98,Y与η增大;Ca/C从0增至1.05,由于Ca O的强化作用,产品气中CO2含量趋近0,H2含量从0.10增至0.98,Y和η增大到峰值。在操作条件为NiO/C=0.83、S/C=4.10、Ca/C=1.05时,地沟油制氢系统性能最优,产品气中H2体积分数可达0.98,Y为1.95,η为0.81。

Hydrogen production via sorption-enhanced chemical looping reforming of waste cooking oil（WCO） not only save fossil fuels but also reduce emissions of green house gas such as CO2. The system is simulated by Aspen Plus and investigated by thermodynamic analysis. The effects of Ni O to carbon molar ratio（NiO/C）,steam to carbon molar ratio（S/C）,and Ca O to carbon molar ratio（Ca/C） on performance indicators,i.e. hydrogen yield（Y）,production gas composition（dry gas）,system exergy efficiency（η）are analyzed. The results show,with the increase of Ni O/C from 0.5 to1.8,H2 concentration declines by 0.01,Y and η both are dropped;increasing S/C from 1 to 5,there is a growth of H2 concentration from 0.85 to 0.98,which lead to the increase of η and Y. With the rise of Ca/C from 0 to 1.05,CO2 is totally captured,H2 concentrations grow up to 0.99,Y and η both are increased. Consequently,with the optimal conditions of Ni O/C 0.83,S/C 4.10 and Ca/C 1.05,H2 concentration is up to 0.98,Y and η both reach to the optimum value,at 1.95 and0.81,respectively.