基于太阳能蓄热过程的甲烷二氧化碳重整研究进展

热化学储能技术因为其储能密度高、热损小、能长距离运输等优点而成为保证太阳能长久稳定供应的关键技术。本文对基于甲烷二氧化碳重整反应的太阳能热化学储热系统研究现状进行了回顾,重点讨论了甲烷重整催化剂、重整反应器以及储能系统整体的传热特性等3个方向的研究进展。指出新型高效催化剂以及反应器开发和性能测试是目前该领域的主要研究方向。发现辐射热损失、非均匀温度分布特性、辐射热流的时变波动特性,以及由此造成的能量与化学反应的不匹配限制了热化学系统能量储存效率的进一步提高,并提出催化剂的催化特性与物性/结构参数依变关系,反应器辐射吸收特性、传热传质特性和反应特性之间的相互作用机制,以及系统时变动态特性与反应物流/辐射能流的匹配关系是建立甲烷重整热化学储能系统优化设计理论亟待解决的关键问题。

Advances of CO2 reforming of methane based on the solar energy storage

School of Chemical Engineering and Technology,Xi'an Jiaotong University,Xi'an 710049,Shaanxi,China)Abstract:Thermochemical energy storage is the key technique to guarantee long term and steady supply of solar energy due to its advantages of high energy density,low heat loss as well as transportability over long distance. In this work,the development of CO₂ reforming of methane that has been applied in the solar thermochemical energy storage system was summarized. Particular emphasis was put on the studies of methane reforming catalyst,methane reforming reactor,and thermal analysis of thermochemical energy storage system. New high-efficiency catalysts and reforming reactors were the main interests of the current researches. Radiation heat loss,non-uniform temperature distribution,time-varying radiation heat flux,as well as the mismatching between energy and chemical reaction restricted the improvement of thermochemical energy storage efficiency. In order to further improve the performance of thermochemical energy storage system and establish its optimization design theory,some key questions were proposed to be answered,including the relationship between the catalytic performance and properties/structure parameters of the catalyst,the interaction mechanism of thermal radiation absorption,heat/mass transfer and thermochemical reaction characteristics of the chemical reactor,as well as the time-varying dynamic features and matching relationship with radiation heat flux of the thermochemical system.