热化学硫碘开路循环制氢系统的设计与模拟

Process design and simulation of open-loop sulfur-iodine thermo-chemical cycle for hydrogen production

为了对热化学硫碘开路循环制氢系统进行优化设计及热效率评估,利用大型化工流程模拟软件AspenPlus对硫碘开路循环联产氢气和硫酸系统进行设计和模拟,计算质量、能量平衡及热效率.在考虑泵功和废热回收的情况下,开路系统的最高计算热效率达到66.2%.其次,利用灵敏度分析,分别考察HI精馏塔回流比、精馏塔压力、HI相循环量、HI分解率和产品硫酸质量分数5个设计参数对系统效率的影响.结果显示,HI相循环量和精馏塔回流比是影响系统效率的主要因素,其他参数对效率影响较小.通过优化本生反应操作条件可显著减少HI相的循环量,提高系统效率.计算结果与文献参考值接近,为今后大规模硫碘循环制氢系统的设计及优化提供参考.

In order to optimize the process and thermal efficiency of the open-loop sulfur-iodine （SI） ther- too-chemical cycle for production of hydrogen, a flowsheet of open-loop SI thermo-chemical cycle was designed and simulated by Aspen Plus. The heat and mass balance as well as thermal efficiency were first calculated. The maximum thermal efficiency of the process was 66.2% considering waste heat recovery and pumping power. Secondly, through sensitivity analysis, the effects of 5 operating parameters like. reflux ratio at HI distillation column, pressure in HI distillation column, flow rate of HI phase, conversion ratio of HI and mass fraction of H2 SO4 were evaluated to the thermal efficiency. Results show that the flow rate of HI phase and reflux ratio of the HI distillation column are the primary paramenters influence the total efficiency, while the other parameters are not so obviously. Through optimization of the Bunsen reactor operation condition, the flow rate of the HI phase can be reduced therefore improve the whole thermal efficiency. The simulation results agree well with published datas and can be used as reference for design and optimization of the large scale SI thermo-chemical cycle H2 production system.