Experimental study of the steady and dynamic efficiencies of a solar methanol steam reforming reactor filled with a phase change material for hydrogen production
MA Zhao, CHENG Zedong, HE Yaling
Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, China
Abstract：Solar thermochemical reactors are a promising way to produce clean hydrogen energy. However, the operation of a reactor driven by solar irradiation will fluctuate as the solar irradiation changes. This study analyzed the thermal management of a solar methanol steam reforming reactor for hydrogen production with phase change material (PCM) in the reactor. The analyses considered two latent heat type thermochemical reactors. The thermal and hydrogen production characteristics of these thermochemical reactors were investigated experimentally to show the influence of the heat flux variations. Then, the models were used to study the effect of the phase change material position on the reactor hydrogen production. Finally, the dynamic efficiencies of the latent heat type reactors were compared with that of the original design to show that when the reactor surface heat flux reaches 7 kW/m2, the H2 proportion of the production rate is 0.713 and the methanol conversion efficiency is 0.956. Increasing the heat flux increases the methanol conversion efficiency. Adding the PCM in the shell reduces the required catalyst mass by 66.0% while adding the PCM in the tube side reduces the required catalyst mass by 13.5% for steady-state operation while the reactor continues to operate efficiently. For dynamic operation, the methanol conversion efficiency is reduced by 23.4% when the PCM is added to the shell side and by 13.7% when the PCM is added to the tube side while the reactor thermal inertia is improved to cope with sudden heat flux changes.
马朝, 程泽东, 何雅玲. 相变储热型太阳能甲醇重整反应器稳态及动态制氢特性的实验研究[J]. 清华大学学报（自然科学版）, 2021, 61(12): 1371-1378.
MA Zhao, CHENG Zedong, HE Yaling. Experimental study of the steady and dynamic efficiencies of a solar methanol steam reforming reactor filled with a phase change material for hydrogen production. Journal of Tsinghua University(Science and Technology), 2021, 61(12): 1371-1378.
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2021, Vol. 61 
