高温蒸汽电解制氢系统温度敏感性分析

摘要

In this study, the temperature sensitive analysis model of the high temperature steam electrolysis (HTSE) system was established through electrochemical method. Temperature sensitivity of the HTSE system was analyzed using this model. The concept of temperature sensitive coefficient was put forward originally. Qualitative researches show the temperature sensitive coefficient increase with operation temperatures increasing under various electrical efficiency (ηel), electrolysis efficiency (ηes), and thermal efficiency (ηth), which indicate the overall system efficiency of the HTSE system increases with operation temperatures increasing. And the temperature sensitive coefficient increase with ηel and ηth increasing, while ηes has little effect on the temperature sensitive coefficient. Quantitative researches show the temperature sensitive coefficient is 1.4 with the operation temperatures in the range of 750-950 ℃, which indicates the overall system efficiency increases about 10.5% and 12%, when the operation temperatures of the HTSE system are 800 and 900 ℃, respectively. Then the overall system efficiency of the actual HTGR coupled with HTSE system is as high as 55.8% and 56.5%, respectively, which is about two times higher than that of the conventional alkaline water electrolysis.%通过电化学方法建立高温蒸汽电解制氢系统温度敏感性分析的数学模型,通过该模型对系统温度敏感性进行分析,并提出温度敏感系数的概念.定性的研究结果表明,在不同发电效率、电解效率以及热效率下,温度敏感系数均随着工作温度的增加而增大.这表明,系统总效率随着温度的升高而增大,且随着发电效率和热效率的增加,温度敏感系数也随之增大,但电解效率对温度敏感系数影响较小.定量的研究结果表明,工作温度为750～950 ℃的高温蒸汽电解制氢系统的温度敏感系数约为1.40,即系统工作温度分别为800和900 ℃时,由于温度升高而使系统总效率分别增加约10.5%和12%;相应的实际总制氢效率可分别高达55.8%和56.5%,约是常规碱性水电解制氢效率的两倍.