丙烷化学链氧化脱氢过程模拟与能耗分析

Process Simulation and Energy Consumption Analysis of Chemical Looping Oxidative Dehydrogenation of Propane

采用金属氧化物催化丙烷氧化脱氢的化学链反应过程,利用晶格氧选择性燃烧生成氢,推动反应热力学平衡向生成丙烯方向移动,提高丙烯收率,降低过程热负荷;基于Aspen Plus软件对传统丙烷脱氢工艺(Oleflex)和化学链氧化脱氢工艺进行全流程模拟,对比分析两工艺的能耗;并基于流程模拟与分析,对氢气转化率和反应-再生系统设计进行了讨论。结果表明,对于化学链氧化脱氢工艺,由于不需要临氢环境,氢气与催化剂晶格氧及积炭的反应使其能耗比Oleflex工艺降低43.01%。若采用丙烯-丙烷热泵精馏分离技术替代传统精馏技术,化学链氧化脱氢过程总能耗比Oleflex工艺可进一步降低。随着氢气转化率的提高,脱氢反应系统对下游供热的能力将逐渐提升。

Here,propane oxidative dehydrogenation process with the concept of chemical looping,and selective hydrogen combustion with lattice oxygen were employed to shift the thermodynamic equilibrium,promoting the propylene production and decreasing the heat duty.Oleflex conventional propane dehydrogenation process and chemical looping oxidative dehydrogenation process were further simulated by using Aspen Plus,to investigate their energy consumptions.The results show that chemical looping oxidative dehydrogenation process reduces the energy consumption by 43.01%compared with the Oleflex process,because of no needs for hydrogen environment,reactions on the hydrogen from the dehydrogenation with lattice oxygen in the catalyst,and the exist of coke reaction.It is also found that the overall energy consumption has been further reduced with the heat pump distillation technology.Based on process simulation and analysis,hydrogen conversion rate and the reaction-regeneration system design were also discussed.The results show that the ability of heat supply for dehydrogenation reaction system to the downstream could be improved when the hydrogen conversion rate increases.