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研制中，本项目已研制的旋转式太阳能反应堆(1kW)模型由八步工艺改进为三步工艺。设计并制作了10kW旋转式太阳能反应堆的2kW模型(转子比直径=50 cm，TO_2=1500℃，聚束流密度=2100kW/m~2，ωt=2.5rpm)。以镍铁氧体为反应陶瓷，在2^&lt；ND&gt；模型上进行了性能测试，在TO2=1250℃时，放出的氧气和水蒸气的回收率达到80%。由于TO_2=125℃的最高温度的限制，氢气的生成步骤没有实现。为估算东京工业大学聚光系统(TIT-BD系统)在使用旋转式太阳能反应堆时聚光点的实际通量大小，开发了太阳能聚光系统模拟器，并开发了CG软件将模拟结果以CG的形式表达在TIT-BD系统上。在定日镜的研制中，GPS系统作为一种跟踪太阳的调节系统被发现优于三点识别系统。在TIT-BD系统的开发中，开发了多环中心反射镜系统、腔式熔盐接收器和交叉束定日镜系统；在反应陶瓷的开发中，研究了YSZ与铁氧体之间的固溶体系统，并发现该系统可用于旋转式太阳能反应堆的两步分水工艺。在旋转式太阳能反应堆放氧阶段的试验中，发现在旋转式太阳能反应堆放氧阶段，通过集中红外光照射陶瓷，在快速升温过程中出现了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.