基于金属氧化物的两步法太阳能热化学循环制备燃料研究现状与展望

Review and prospects of two-step solar thermochemical cycle for preparing fuels based on metal oxides

基于金属氧化物的两步法太阳能热化学循环可以生产清洁的燃料,具有理论效率高、二氧化碳零排放等优点,有望成为实现碳中和的有效途径,但存在太阳能到化学能能源转化效率不高的问题。从材料基对、反应器设计、多能互补系统优化等方面入手,着重分析了影响太阳能到化学能能源转化效率的因素。总结了材料基对研究的发展历程,指出了密度泛函方法和机器学习方法在材料基对筛选方面的重要作用。结合材料特性,分析了泡沫陶瓷/蜂窝结构反应器、粒子反应器和膜反应器的适用范围及优缺点,指出更优的孔隙率和合适的粒子半径可以加快材料基对的升温速率,并且可以有效减少热损失;同时,大规模可连续式设计可以实现对太阳能的高效利用。系统优化方面,综合分析了数字孪生等新技术在多能互补系统发挥的作用。最后,对高温太阳能热化学循环制备燃料技术未来的发展提出了建议。

Clean fuels can be prepared by two-step solar thermochemical cycle based on metal oxides.This method is expected to be an effective way to carbon neutrality for its high theoretical efficiency and zero CO_(2) emissions.However,its energy conversion efficiency from solar energy to chemical energy is unsatisfactory.The analysis on the method is made from the oxide pairs,reactor design and optimization of multi-energy complementation systems,and focuses on the factors affecting the conversion efficiency of solar energy to chemical energy.In terms of materials,we expound the development history of oxide pairs and point out the importance of DFT and machine learning in oxide pairs screening.Considering the characteristics of different materials,the application scope,advantages and disadvantages of foam ceramic/honeycombstructure reactors,particle reactors and membrane reactors are analyzed.Proper porosity and particle radius can speed up the heating rate of the oxide pairs,and effectively reduce heat loss.At the same time,large-scale continuous design can also improve the efficient use of solar energy.In terms of system optimization,the roles of new technologies,such as digital twins,in multi-energy complementary systems are comprehensively analyzed.In the end,the prospects of high-temperature solar thermochemical cycle for preparing fuels and the suggestions for the technology are put forward.