SMR-LNG联合液氢制取系统模拟与效益评价

Simulation and Benefit Evaluation of SMR-LNG Combined Liquid Hydrogen Production System

提出了一种基于LNG接收站冷能与甲烷蒸汽重整制氢过程的协同制取液氢工艺系统——SMR-LNG联合液氢制取系统,利用多流LNG换热器实现甲烷蒸汽重整制氢工艺与LNG预冷液化氢气工艺的耦合。通过Aspen HYSYS软件对所提出的工艺系统进行建模与模拟计算。当LNG供应量为50 t/h时,系统能够产出质量流量为5.89 t/h、纯度为99.99%的液氢。氢气液化子系统比能耗比传统氢气提纯及液化工艺低,利用LNG冷能具有良好的节能效益。系统中所有LNG换热器的火用损失率为28.0%,所有反应器的火用损失率为26.4%,所有冷却器的火用损失率为13.3%,所有压缩机的火用损失率为8.2%,所有膨胀机的火用损失率为7.0%。这5类设备的火用损失率很高,隐含着系统的节能改进机会。

A collaborative liquid hydrogen production process system based on LNG receiving station cold energy and steam methane reforming(SMR)hydrogen production process,SMR-LNG combined liquid hydrogen production system,is proposed.The system utilizes a multi flow LNG heat exchanger to achieve coupling between steam methane reforming hydrogen production process and LNG pre cooled liquefied hydrogen production process.The proposed process system is modeled and simulated by Aspen HYSYS software.When the LNG supply is 50 t/h,the system can produce liquid hydrogen with a mass flow rate of 5.89 t/h and a purity of 99.99%.The hydrogen liquefaction subsystem has lower specific energy consumption compared to traditional hydrogen purification and liquefaction processes,and the use of LNG cold energy has good energysaving benefits.The exergy loss rate of all LNG heat exchangers in the system is 28.0%,the exergy loss rate of all reactors is 26.4%,the exergy loss rate of all coolers is 13.3%,the exergy loss rate of all compressors is 8.2%,and the exergy loss rate of all expanders is 7.0%.The exergy loss rate of these 5 types of equipment is very high,which implies the opportunity for energy saving improvement in the system.