应用于碘硫循环制氢中碘化氢浓缩分离的EED-精馏耦合工艺研究

Iodine-Sulfur thermochemical cycle is one of the most promising massive hydrogen production methods. Separation of HI from HI-H2O-I2 mixture produced in the process is essential for the energy utilization efficiency, because of the presence of HI-H2O azeotropy. A novel method, Electro-Electrodialysis (EED)-vacuum distillation coupling process is proposed to overcome the disadvantage of HI inverse transportation in conventional EED. Furthermore, pressure difference between anolyte and catholyte will also promote the concentration of HI in catholyte, leading to the achievement of high effective HI separation. In this research, HI concentration by EED stack with the presence of pressure difference between anolyte and catholyte, and vacuum distillation of hyperazeotropic mixture will be studied systematically, based on which, EED-distillation coupling operation for HI-H2O-I2 will be researched. The optimized condition and coupling mechanism of the operation will be detected, aiming at the promotion of the HI separation and also the efficiency of the whole Iodine-Sulfur thermochemical cycle.

碘硫循环分解水是一种清洁高效的大规模制氢方法，但由于碘化氢(HI)与水构成共沸体系，使得HI-H2O-I2物料中HI的浓缩、分离成为了阻碍碘硫循环高效产氢的瓶颈步骤。本申请提出电解电渗析(EED)-减压精馏耦合工艺，克服常规EED过程中阴、阳两极物料浓差较大时出现的HI反向迁移等问题，并以阴、阳两极间的压差促进阴极区HI的浓缩，在过程耦合与强化的基础上，大幅度提高HI的浓缩分离效率。本课题将针对阴、阳极区存在压差情况下的EED工艺，超共沸HI-H2O-I2的减压精馏，以及EED-减压精馏耦合过程开展系统、深入的基础研究。在实验研究与Aspen软件模拟相结合的基础上，力图在EED-精馏设计、过程耦合机理等方面取得突破，充分发挥EED-精馏的协同作用，为HI的高效浓缩分离，乃至整个碘硫循环制氢过程的高效运行提供理论和实验基础。

碘硫循环分解水是一种清洁高效的大规模制氢方法，但由于碘化氢(HI)与水构成共沸体系，使得HI-H2O-I2物料中HI的浓缩、分离成为了阻碍碘硫循环高效产氢的瓶颈步骤。本项目将电解电渗析(EED)和减压精馏耦合起来，克服了常规EED过程中阴、阳两极物料浓差较大时出现的HI反向迁移等问题，并以阴、阳两极间的压差促进阴极区HI的浓缩。在过程耦合与强化的基础上，大幅度提高了HI的浓缩分离效率。本课题针对HIx物性基础数据、HIx组成快速分析，以及阴、阳极区存在压差情况下的EED工艺，超共沸HI-H2O-I2的减压精馏，EED-减压精馏耦合过程开展了系统、深入的基础研究。在实验研究与Aspen软件模拟相结合的基础上，在EED-精馏设计、过程耦合机理等方面取得了研究成果，充分发挥了EED-精馏的协同作用，为HI的高效浓缩分离，乃至整个碘硫循环制氢过程的高效运行提供了一定的理论和实验基础。