Development of conversion technology for concentrated solar thermal energy to solar hydrogen using continuous two step water splitting process

在旋转式太阳能反应堆的开发中，<st>本项目先前制造的旋转式太阳能反应堆（1 kW）的1^模型的八步工艺已改进为三步工艺。设计<nd>并制作了10 kW旋转式太阳能反应堆的2 ×模型（转子比直径50 cm，To_2=1500℃，集中束流通量2100 kW/m^2，ωt= 2.5rpm）。以<nd>镍铁氧体为反应陶瓷，对2 × 10 ~（-3）型反应器进行了性能测试，在1250℃时，可回收80%的氧气和水蒸气用于制氢。由于最高反应温度To_2= 1250 ℃的限制，H_2生成步骤未能实现。为了估算东京工业大学光束式太阳能聚光系统（TIT-BD系统）中使用旋转式太阳能反应堆时聚光点处的实际通量大小，开发了太阳能聚光系统模拟器，并开发了CG软件，利用CG表达TIT-BD系统的模拟结果。在定日镜的研制过程中，发现GPS系统作为跟踪太阳的调节系统比三点识别系统具有上级的优越性。在TIT-BD系统的开发中，开发了多环中心反射器系统、腔式熔盐接收器和交叉束定日镜场设计。在反应陶瓷的开发中，研究了YSZ和铁氧体之间的固溶体系统，并发现其用于使用旋转式太阳能反应器的两步水分解过程。在旋转式太阳能反应器释氧阶段的试验中，发现了在旋转式太阳能反应器释氧阶段陶瓷在集中红外线辐照下迅速升温过程中，反应陶瓷的中间阶段。

In the development on the rotary type solar reactor, the eight-step process of the 1^<st> model of the rotary type solar reactor (1kW), which had been fabricated previously on this project, has been improved to three-step process. The 2^<nd> model of the 10kW rotary type solar reactor was designed and fabricated (the specific ; diameter of the rotor= 50cm, To_2=1500℃, concentrated beam flux=2100kW/m^2, ωt=2.5 rpm. The performance test on the 2^<nd> model was carried out using the Ni-ferrite as reactive ceramics, and 80% recovery of the released O_2 and steam for H2 generation were obtained at To_2=1250℃. The H2 generation step was not achieved because of the limitation of the maximum temperature of To_2=125O℃. The simulator for solar concentration system was developed to estimate the practical flux magnitude in the Tokyo Tech Beam-down solar concentration system (TIT-BD system) at the focus point for using the rotary type solar reactor, and the CG software was developed to express the simulation result on TIT-BD system by CG. In the development on the heliostat, GPS system as a regulation system for tracking the sun was found to be superior to the three points recognition system. In the, development on the TIT-BD system, multi-ring central reflector system, cavity type molten salt receiver, and cross-beam heliostat field design were developed.In the development of the reactive ceramics, the solid solution system between YSZ and the ferrites has been studied and was found to be used for the two-step water splitting process using rotary type solar reactor. In test of the O_2-releasing step of rotary type solar reactor, an intermediate stage of the reactive ceramics was discovered during a rapid temperature increase by the concentrated infra-red beam irradiation to the ceramics in the O_2-releasing step in the rotary type solar reactor.